11da177e4SLinus Torvalds /*
21da177e4SLinus Torvalds ===============================================================================
31da177e4SLinus Torvalds
41da177e4SLinus Torvalds This C source file is part of the SoftFloat IEC/IEEE Floating-point
51da177e4SLinus Torvalds Arithmetic Package, Release 2.
61da177e4SLinus Torvalds
71da177e4SLinus Torvalds Written by John R. Hauser. This work was made possible in part by the
81da177e4SLinus Torvalds International Computer Science Institute, located at Suite 600, 1947 Center
91da177e4SLinus Torvalds Street, Berkeley, California 94704. Funding was partially provided by the
101da177e4SLinus Torvalds National Science Foundation under grant MIP-9311980. The original version
111da177e4SLinus Torvalds of this code was written as part of a project to build a fixed-point vector
121da177e4SLinus Torvalds processor in collaboration with the University of California at Berkeley,
131da177e4SLinus Torvalds overseen by Profs. Nelson Morgan and John Wawrzynek. More information
14*50a23e6eSJustin P. Mattock is available through the web page
15*50a23e6eSJustin P. Mattock http://www.jhauser.us/arithmetic/SoftFloat-2b/SoftFloat-source.txt
161da177e4SLinus Torvalds
171da177e4SLinus Torvalds THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort
181da177e4SLinus Torvalds has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
191da177e4SLinus Torvalds TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO
201da177e4SLinus Torvalds PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
211da177e4SLinus Torvalds AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
221da177e4SLinus Torvalds
231da177e4SLinus Torvalds Derivative works are acceptable, even for commercial purposes, so long as
241da177e4SLinus Torvalds (1) they include prominent notice that the work is derivative, and (2) they
251da177e4SLinus Torvalds include prominent notice akin to these three paragraphs for those parts of
261da177e4SLinus Torvalds this code that are retained.
271da177e4SLinus Torvalds
281da177e4SLinus Torvalds ===============================================================================
291da177e4SLinus Torvalds */
301da177e4SLinus Torvalds
31c1241c4cSNicolas Pitre #include <asm/div64.h>
32c1241c4cSNicolas Pitre
331da177e4SLinus Torvalds #include "fpa11.h"
341da177e4SLinus Torvalds //#include "milieu.h"
351da177e4SLinus Torvalds //#include "softfloat.h"
361da177e4SLinus Torvalds
371da177e4SLinus Torvalds /*
381da177e4SLinus Torvalds -------------------------------------------------------------------------------
391da177e4SLinus Torvalds Primitive arithmetic functions, including multi-word arithmetic, and
401da177e4SLinus Torvalds division and square root approximations. (Can be specialized to target if
411da177e4SLinus Torvalds desired.)
421da177e4SLinus Torvalds -------------------------------------------------------------------------------
431da177e4SLinus Torvalds */
441da177e4SLinus Torvalds #include "softfloat-macros"
451da177e4SLinus Torvalds
461da177e4SLinus Torvalds /*
471da177e4SLinus Torvalds -------------------------------------------------------------------------------
481da177e4SLinus Torvalds Functions and definitions to determine: (1) whether tininess for underflow
491da177e4SLinus Torvalds is detected before or after rounding by default, (2) what (if anything)
501da177e4SLinus Torvalds happens when exceptions are raised, (3) how signaling NaNs are distinguished
511da177e4SLinus Torvalds from quiet NaNs, (4) the default generated quiet NaNs, and (5) how NaNs
521da177e4SLinus Torvalds are propagated from function inputs to output. These details are target-
531da177e4SLinus Torvalds specific.
541da177e4SLinus Torvalds -------------------------------------------------------------------------------
551da177e4SLinus Torvalds */
561da177e4SLinus Torvalds #include "softfloat-specialize"
571da177e4SLinus Torvalds
581da177e4SLinus Torvalds /*
591da177e4SLinus Torvalds -------------------------------------------------------------------------------
601da177e4SLinus Torvalds Takes a 64-bit fixed-point value `absZ' with binary point between bits 6
611da177e4SLinus Torvalds and 7, and returns the properly rounded 32-bit integer corresponding to the
621da177e4SLinus Torvalds input. If `zSign' is nonzero, the input is negated before being converted
631da177e4SLinus Torvalds to an integer. Bit 63 of `absZ' must be zero. Ordinarily, the fixed-point
641da177e4SLinus Torvalds input is simply rounded to an integer, with the inexact exception raised if
651da177e4SLinus Torvalds the input cannot be represented exactly as an integer. If the fixed-point
661da177e4SLinus Torvalds input is too large, however, the invalid exception is raised and the largest
671da177e4SLinus Torvalds positive or negative integer is returned.
681da177e4SLinus Torvalds -------------------------------------------------------------------------------
691da177e4SLinus Torvalds */
roundAndPackInt32(struct roundingData * roundData,flag zSign,bits64 absZ)70f148af25SRichard Purdie static int32 roundAndPackInt32( struct roundingData *roundData, flag zSign, bits64 absZ )
711da177e4SLinus Torvalds {
721da177e4SLinus Torvalds int8 roundingMode;
731da177e4SLinus Torvalds flag roundNearestEven;
741da177e4SLinus Torvalds int8 roundIncrement, roundBits;
751da177e4SLinus Torvalds int32 z;
761da177e4SLinus Torvalds
77f148af25SRichard Purdie roundingMode = roundData->mode;
781da177e4SLinus Torvalds roundNearestEven = ( roundingMode == float_round_nearest_even );
791da177e4SLinus Torvalds roundIncrement = 0x40;
801da177e4SLinus Torvalds if ( ! roundNearestEven ) {
811da177e4SLinus Torvalds if ( roundingMode == float_round_to_zero ) {
821da177e4SLinus Torvalds roundIncrement = 0;
831da177e4SLinus Torvalds }
841da177e4SLinus Torvalds else {
851da177e4SLinus Torvalds roundIncrement = 0x7F;
861da177e4SLinus Torvalds if ( zSign ) {
871da177e4SLinus Torvalds if ( roundingMode == float_round_up ) roundIncrement = 0;
881da177e4SLinus Torvalds }
891da177e4SLinus Torvalds else {
901da177e4SLinus Torvalds if ( roundingMode == float_round_down ) roundIncrement = 0;
911da177e4SLinus Torvalds }
921da177e4SLinus Torvalds }
931da177e4SLinus Torvalds }
941da177e4SLinus Torvalds roundBits = absZ & 0x7F;
951da177e4SLinus Torvalds absZ = ( absZ + roundIncrement )>>7;
961da177e4SLinus Torvalds absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven );
971da177e4SLinus Torvalds z = absZ;
981da177e4SLinus Torvalds if ( zSign ) z = - z;
991da177e4SLinus Torvalds if ( ( absZ>>32 ) || ( z && ( ( z < 0 ) ^ zSign ) ) ) {
100f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
1011da177e4SLinus Torvalds return zSign ? 0x80000000 : 0x7FFFFFFF;
1021da177e4SLinus Torvalds }
103f148af25SRichard Purdie if ( roundBits ) roundData->exception |= float_flag_inexact;
1041da177e4SLinus Torvalds return z;
1051da177e4SLinus Torvalds
1061da177e4SLinus Torvalds }
1071da177e4SLinus Torvalds
1081da177e4SLinus Torvalds /*
1091da177e4SLinus Torvalds -------------------------------------------------------------------------------
1101da177e4SLinus Torvalds Returns the fraction bits of the single-precision floating-point value `a'.
1111da177e4SLinus Torvalds -------------------------------------------------------------------------------
1121da177e4SLinus Torvalds */
extractFloat32Frac(float32 a)1131da177e4SLinus Torvalds INLINE bits32 extractFloat32Frac( float32 a )
1141da177e4SLinus Torvalds {
1151da177e4SLinus Torvalds
1161da177e4SLinus Torvalds return a & 0x007FFFFF;
1171da177e4SLinus Torvalds
1181da177e4SLinus Torvalds }
1191da177e4SLinus Torvalds
1201da177e4SLinus Torvalds /*
1211da177e4SLinus Torvalds -------------------------------------------------------------------------------
1221da177e4SLinus Torvalds Returns the exponent bits of the single-precision floating-point value `a'.
1231da177e4SLinus Torvalds -------------------------------------------------------------------------------
1241da177e4SLinus Torvalds */
extractFloat32Exp(float32 a)1251da177e4SLinus Torvalds INLINE int16 extractFloat32Exp( float32 a )
1261da177e4SLinus Torvalds {
1271da177e4SLinus Torvalds
1281da177e4SLinus Torvalds return ( a>>23 ) & 0xFF;
1291da177e4SLinus Torvalds
1301da177e4SLinus Torvalds }
1311da177e4SLinus Torvalds
1321da177e4SLinus Torvalds /*
1331da177e4SLinus Torvalds -------------------------------------------------------------------------------
1341da177e4SLinus Torvalds Returns the sign bit of the single-precision floating-point value `a'.
1351da177e4SLinus Torvalds -------------------------------------------------------------------------------
1361da177e4SLinus Torvalds */
1371da177e4SLinus Torvalds #if 0 /* in softfloat.h */
1381da177e4SLinus Torvalds INLINE flag extractFloat32Sign( float32 a )
1391da177e4SLinus Torvalds {
1401da177e4SLinus Torvalds
1411da177e4SLinus Torvalds return a>>31;
1421da177e4SLinus Torvalds
1431da177e4SLinus Torvalds }
1441da177e4SLinus Torvalds #endif
1451da177e4SLinus Torvalds
1461da177e4SLinus Torvalds /*
1471da177e4SLinus Torvalds -------------------------------------------------------------------------------
1481da177e4SLinus Torvalds Normalizes the subnormal single-precision floating-point value represented
1491da177e4SLinus Torvalds by the denormalized significand `aSig'. The normalized exponent and
1501da177e4SLinus Torvalds significand are stored at the locations pointed to by `zExpPtr' and
1511da177e4SLinus Torvalds `zSigPtr', respectively.
1521da177e4SLinus Torvalds -------------------------------------------------------------------------------
1531da177e4SLinus Torvalds */
1541da177e4SLinus Torvalds static void
normalizeFloat32Subnormal(bits32 aSig,int16 * zExpPtr,bits32 * zSigPtr)1551da177e4SLinus Torvalds normalizeFloat32Subnormal( bits32 aSig, int16 *zExpPtr, bits32 *zSigPtr )
1561da177e4SLinus Torvalds {
1571da177e4SLinus Torvalds int8 shiftCount;
1581da177e4SLinus Torvalds
1591da177e4SLinus Torvalds shiftCount = countLeadingZeros32( aSig ) - 8;
1601da177e4SLinus Torvalds *zSigPtr = aSig<<shiftCount;
1611da177e4SLinus Torvalds *zExpPtr = 1 - shiftCount;
1621da177e4SLinus Torvalds
1631da177e4SLinus Torvalds }
1641da177e4SLinus Torvalds
1651da177e4SLinus Torvalds /*
1661da177e4SLinus Torvalds -------------------------------------------------------------------------------
1671da177e4SLinus Torvalds Packs the sign `zSign', exponent `zExp', and significand `zSig' into a
1681da177e4SLinus Torvalds single-precision floating-point value, returning the result. After being
1691da177e4SLinus Torvalds shifted into the proper positions, the three fields are simply added
1701da177e4SLinus Torvalds together to form the result. This means that any integer portion of `zSig'
1711da177e4SLinus Torvalds will be added into the exponent. Since a properly normalized significand
1721da177e4SLinus Torvalds will have an integer portion equal to 1, the `zExp' input should be 1 less
1731da177e4SLinus Torvalds than the desired result exponent whenever `zSig' is a complete, normalized
1741da177e4SLinus Torvalds significand.
1751da177e4SLinus Torvalds -------------------------------------------------------------------------------
1761da177e4SLinus Torvalds */
packFloat32(flag zSign,int16 zExp,bits32 zSig)1771da177e4SLinus Torvalds INLINE float32 packFloat32( flag zSign, int16 zExp, bits32 zSig )
1781da177e4SLinus Torvalds {
1791da177e4SLinus Torvalds #if 0
1801da177e4SLinus Torvalds float32 f;
1811da177e4SLinus Torvalds __asm__("@ packFloat32 \n\
1821da177e4SLinus Torvalds mov %0, %1, asl #31 \n\
1831da177e4SLinus Torvalds orr %0, %2, asl #23 \n\
1841da177e4SLinus Torvalds orr %0, %3"
1851da177e4SLinus Torvalds : /* no outputs */
1861da177e4SLinus Torvalds : "g" (f), "g" (zSign), "g" (zExp), "g" (zSig)
1871da177e4SLinus Torvalds : "cc");
1881da177e4SLinus Torvalds return f;
1891da177e4SLinus Torvalds #else
1901da177e4SLinus Torvalds return ( ( (bits32) zSign )<<31 ) + ( ( (bits32) zExp )<<23 ) + zSig;
1911da177e4SLinus Torvalds #endif
1921da177e4SLinus Torvalds }
1931da177e4SLinus Torvalds
1941da177e4SLinus Torvalds /*
1951da177e4SLinus Torvalds -------------------------------------------------------------------------------
1961da177e4SLinus Torvalds Takes an abstract floating-point value having sign `zSign', exponent `zExp',
1971da177e4SLinus Torvalds and significand `zSig', and returns the proper single-precision floating-
1981da177e4SLinus Torvalds point value corresponding to the abstract input. Ordinarily, the abstract
1991da177e4SLinus Torvalds value is simply rounded and packed into the single-precision format, with
2001da177e4SLinus Torvalds the inexact exception raised if the abstract input cannot be represented
2011da177e4SLinus Torvalds exactly. If the abstract value is too large, however, the overflow and
2021da177e4SLinus Torvalds inexact exceptions are raised and an infinity or maximal finite value is
2031da177e4SLinus Torvalds returned. If the abstract value is too small, the input value is rounded to
2041da177e4SLinus Torvalds a subnormal number, and the underflow and inexact exceptions are raised if
2051da177e4SLinus Torvalds the abstract input cannot be represented exactly as a subnormal single-
2061da177e4SLinus Torvalds precision floating-point number.
2071da177e4SLinus Torvalds The input significand `zSig' has its binary point between bits 30
2081da177e4SLinus Torvalds and 29, which is 7 bits to the left of the usual location. This shifted
2091da177e4SLinus Torvalds significand must be normalized or smaller. If `zSig' is not normalized,
2101da177e4SLinus Torvalds `zExp' must be 0; in that case, the result returned is a subnormal number,
2111da177e4SLinus Torvalds and it must not require rounding. In the usual case that `zSig' is
2121da177e4SLinus Torvalds normalized, `zExp' must be 1 less than the ``true'' floating-point exponent.
2131da177e4SLinus Torvalds The handling of underflow and overflow follows the IEC/IEEE Standard for
2141da177e4SLinus Torvalds Binary Floating-point Arithmetic.
2151da177e4SLinus Torvalds -------------------------------------------------------------------------------
2161da177e4SLinus Torvalds */
roundAndPackFloat32(struct roundingData * roundData,flag zSign,int16 zExp,bits32 zSig)217f148af25SRichard Purdie static float32 roundAndPackFloat32( struct roundingData *roundData, flag zSign, int16 zExp, bits32 zSig )
2181da177e4SLinus Torvalds {
2191da177e4SLinus Torvalds int8 roundingMode;
2201da177e4SLinus Torvalds flag roundNearestEven;
2211da177e4SLinus Torvalds int8 roundIncrement, roundBits;
2221da177e4SLinus Torvalds flag isTiny;
2231da177e4SLinus Torvalds
224f148af25SRichard Purdie roundingMode = roundData->mode;
2251da177e4SLinus Torvalds roundNearestEven = ( roundingMode == float_round_nearest_even );
2261da177e4SLinus Torvalds roundIncrement = 0x40;
2271da177e4SLinus Torvalds if ( ! roundNearestEven ) {
2281da177e4SLinus Torvalds if ( roundingMode == float_round_to_zero ) {
2291da177e4SLinus Torvalds roundIncrement = 0;
2301da177e4SLinus Torvalds }
2311da177e4SLinus Torvalds else {
2321da177e4SLinus Torvalds roundIncrement = 0x7F;
2331da177e4SLinus Torvalds if ( zSign ) {
2341da177e4SLinus Torvalds if ( roundingMode == float_round_up ) roundIncrement = 0;
2351da177e4SLinus Torvalds }
2361da177e4SLinus Torvalds else {
2371da177e4SLinus Torvalds if ( roundingMode == float_round_down ) roundIncrement = 0;
2381da177e4SLinus Torvalds }
2391da177e4SLinus Torvalds }
2401da177e4SLinus Torvalds }
2411da177e4SLinus Torvalds roundBits = zSig & 0x7F;
2421da177e4SLinus Torvalds if ( 0xFD <= (bits16) zExp ) {
2431da177e4SLinus Torvalds if ( ( 0xFD < zExp )
2441da177e4SLinus Torvalds || ( ( zExp == 0xFD )
2451da177e4SLinus Torvalds && ( (sbits32) ( zSig + roundIncrement ) < 0 ) )
2461da177e4SLinus Torvalds ) {
247f148af25SRichard Purdie roundData->exception |= float_flag_overflow | float_flag_inexact;
2481da177e4SLinus Torvalds return packFloat32( zSign, 0xFF, 0 ) - ( roundIncrement == 0 );
2491da177e4SLinus Torvalds }
2501da177e4SLinus Torvalds if ( zExp < 0 ) {
2511da177e4SLinus Torvalds isTiny =
2521da177e4SLinus Torvalds ( float_detect_tininess == float_tininess_before_rounding )
2531da177e4SLinus Torvalds || ( zExp < -1 )
2541da177e4SLinus Torvalds || ( zSig + roundIncrement < 0x80000000 );
2551da177e4SLinus Torvalds shift32RightJamming( zSig, - zExp, &zSig );
2561da177e4SLinus Torvalds zExp = 0;
2571da177e4SLinus Torvalds roundBits = zSig & 0x7F;
258f148af25SRichard Purdie if ( isTiny && roundBits ) roundData->exception |= float_flag_underflow;
2591da177e4SLinus Torvalds }
2601da177e4SLinus Torvalds }
261f148af25SRichard Purdie if ( roundBits ) roundData->exception |= float_flag_inexact;
2621da177e4SLinus Torvalds zSig = ( zSig + roundIncrement )>>7;
2631da177e4SLinus Torvalds zSig &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven );
2641da177e4SLinus Torvalds if ( zSig == 0 ) zExp = 0;
2651da177e4SLinus Torvalds return packFloat32( zSign, zExp, zSig );
2661da177e4SLinus Torvalds
2671da177e4SLinus Torvalds }
2681da177e4SLinus Torvalds
2691da177e4SLinus Torvalds /*
2701da177e4SLinus Torvalds -------------------------------------------------------------------------------
2711da177e4SLinus Torvalds Takes an abstract floating-point value having sign `zSign', exponent `zExp',
2721da177e4SLinus Torvalds and significand `zSig', and returns the proper single-precision floating-
2731da177e4SLinus Torvalds point value corresponding to the abstract input. This routine is just like
2741da177e4SLinus Torvalds `roundAndPackFloat32' except that `zSig' does not have to be normalized in
2751da177e4SLinus Torvalds any way. In all cases, `zExp' must be 1 less than the ``true'' floating-
2761da177e4SLinus Torvalds point exponent.
2771da177e4SLinus Torvalds -------------------------------------------------------------------------------
2781da177e4SLinus Torvalds */
2791da177e4SLinus Torvalds static float32
normalizeRoundAndPackFloat32(struct roundingData * roundData,flag zSign,int16 zExp,bits32 zSig)280f148af25SRichard Purdie normalizeRoundAndPackFloat32( struct roundingData *roundData, flag zSign, int16 zExp, bits32 zSig )
2811da177e4SLinus Torvalds {
2821da177e4SLinus Torvalds int8 shiftCount;
2831da177e4SLinus Torvalds
2841da177e4SLinus Torvalds shiftCount = countLeadingZeros32( zSig ) - 1;
285f148af25SRichard Purdie return roundAndPackFloat32( roundData, zSign, zExp - shiftCount, zSig<<shiftCount );
2861da177e4SLinus Torvalds
2871da177e4SLinus Torvalds }
2881da177e4SLinus Torvalds
2891da177e4SLinus Torvalds /*
2901da177e4SLinus Torvalds -------------------------------------------------------------------------------
2911da177e4SLinus Torvalds Returns the fraction bits of the double-precision floating-point value `a'.
2921da177e4SLinus Torvalds -------------------------------------------------------------------------------
2931da177e4SLinus Torvalds */
extractFloat64Frac(float64 a)2941da177e4SLinus Torvalds INLINE bits64 extractFloat64Frac( float64 a )
2951da177e4SLinus Torvalds {
2961da177e4SLinus Torvalds
2971da177e4SLinus Torvalds return a & LIT64( 0x000FFFFFFFFFFFFF );
2981da177e4SLinus Torvalds
2991da177e4SLinus Torvalds }
3001da177e4SLinus Torvalds
3011da177e4SLinus Torvalds /*
3021da177e4SLinus Torvalds -------------------------------------------------------------------------------
3031da177e4SLinus Torvalds Returns the exponent bits of the double-precision floating-point value `a'.
3041da177e4SLinus Torvalds -------------------------------------------------------------------------------
3051da177e4SLinus Torvalds */
extractFloat64Exp(float64 a)3061da177e4SLinus Torvalds INLINE int16 extractFloat64Exp( float64 a )
3071da177e4SLinus Torvalds {
3081da177e4SLinus Torvalds
3091da177e4SLinus Torvalds return ( a>>52 ) & 0x7FF;
3101da177e4SLinus Torvalds
3111da177e4SLinus Torvalds }
3121da177e4SLinus Torvalds
3131da177e4SLinus Torvalds /*
3141da177e4SLinus Torvalds -------------------------------------------------------------------------------
3151da177e4SLinus Torvalds Returns the sign bit of the double-precision floating-point value `a'.
3161da177e4SLinus Torvalds -------------------------------------------------------------------------------
3171da177e4SLinus Torvalds */
3181da177e4SLinus Torvalds #if 0 /* in softfloat.h */
3191da177e4SLinus Torvalds INLINE flag extractFloat64Sign( float64 a )
3201da177e4SLinus Torvalds {
3211da177e4SLinus Torvalds
3221da177e4SLinus Torvalds return a>>63;
3231da177e4SLinus Torvalds
3241da177e4SLinus Torvalds }
3251da177e4SLinus Torvalds #endif
3261da177e4SLinus Torvalds
3271da177e4SLinus Torvalds /*
3281da177e4SLinus Torvalds -------------------------------------------------------------------------------
3291da177e4SLinus Torvalds Normalizes the subnormal double-precision floating-point value represented
3301da177e4SLinus Torvalds by the denormalized significand `aSig'. The normalized exponent and
3311da177e4SLinus Torvalds significand are stored at the locations pointed to by `zExpPtr' and
3321da177e4SLinus Torvalds `zSigPtr', respectively.
3331da177e4SLinus Torvalds -------------------------------------------------------------------------------
3341da177e4SLinus Torvalds */
3351da177e4SLinus Torvalds static void
normalizeFloat64Subnormal(bits64 aSig,int16 * zExpPtr,bits64 * zSigPtr)3361da177e4SLinus Torvalds normalizeFloat64Subnormal( bits64 aSig, int16 *zExpPtr, bits64 *zSigPtr )
3371da177e4SLinus Torvalds {
3381da177e4SLinus Torvalds int8 shiftCount;
3391da177e4SLinus Torvalds
3401da177e4SLinus Torvalds shiftCount = countLeadingZeros64( aSig ) - 11;
3411da177e4SLinus Torvalds *zSigPtr = aSig<<shiftCount;
3421da177e4SLinus Torvalds *zExpPtr = 1 - shiftCount;
3431da177e4SLinus Torvalds
3441da177e4SLinus Torvalds }
3451da177e4SLinus Torvalds
3461da177e4SLinus Torvalds /*
3471da177e4SLinus Torvalds -------------------------------------------------------------------------------
3481da177e4SLinus Torvalds Packs the sign `zSign', exponent `zExp', and significand `zSig' into a
3491da177e4SLinus Torvalds double-precision floating-point value, returning the result. After being
3501da177e4SLinus Torvalds shifted into the proper positions, the three fields are simply added
3511da177e4SLinus Torvalds together to form the result. This means that any integer portion of `zSig'
3521da177e4SLinus Torvalds will be added into the exponent. Since a properly normalized significand
3531da177e4SLinus Torvalds will have an integer portion equal to 1, the `zExp' input should be 1 less
3541da177e4SLinus Torvalds than the desired result exponent whenever `zSig' is a complete, normalized
3551da177e4SLinus Torvalds significand.
3561da177e4SLinus Torvalds -------------------------------------------------------------------------------
3571da177e4SLinus Torvalds */
packFloat64(flag zSign,int16 zExp,bits64 zSig)3581da177e4SLinus Torvalds INLINE float64 packFloat64( flag zSign, int16 zExp, bits64 zSig )
3591da177e4SLinus Torvalds {
3601da177e4SLinus Torvalds
3611da177e4SLinus Torvalds return ( ( (bits64) zSign )<<63 ) + ( ( (bits64) zExp )<<52 ) + zSig;
3621da177e4SLinus Torvalds
3631da177e4SLinus Torvalds }
3641da177e4SLinus Torvalds
3651da177e4SLinus Torvalds /*
3661da177e4SLinus Torvalds -------------------------------------------------------------------------------
3671da177e4SLinus Torvalds Takes an abstract floating-point value having sign `zSign', exponent `zExp',
3681da177e4SLinus Torvalds and significand `zSig', and returns the proper double-precision floating-
3691da177e4SLinus Torvalds point value corresponding to the abstract input. Ordinarily, the abstract
3701da177e4SLinus Torvalds value is simply rounded and packed into the double-precision format, with
3711da177e4SLinus Torvalds the inexact exception raised if the abstract input cannot be represented
3721da177e4SLinus Torvalds exactly. If the abstract value is too large, however, the overflow and
3731da177e4SLinus Torvalds inexact exceptions are raised and an infinity or maximal finite value is
3741da177e4SLinus Torvalds returned. If the abstract value is too small, the input value is rounded to
3751da177e4SLinus Torvalds a subnormal number, and the underflow and inexact exceptions are raised if
3761da177e4SLinus Torvalds the abstract input cannot be represented exactly as a subnormal double-
3771da177e4SLinus Torvalds precision floating-point number.
3781da177e4SLinus Torvalds The input significand `zSig' has its binary point between bits 62
3791da177e4SLinus Torvalds and 61, which is 10 bits to the left of the usual location. This shifted
3801da177e4SLinus Torvalds significand must be normalized or smaller. If `zSig' is not normalized,
3811da177e4SLinus Torvalds `zExp' must be 0; in that case, the result returned is a subnormal number,
3821da177e4SLinus Torvalds and it must not require rounding. In the usual case that `zSig' is
3831da177e4SLinus Torvalds normalized, `zExp' must be 1 less than the ``true'' floating-point exponent.
3841da177e4SLinus Torvalds The handling of underflow and overflow follows the IEC/IEEE Standard for
3851da177e4SLinus Torvalds Binary Floating-point Arithmetic.
3861da177e4SLinus Torvalds -------------------------------------------------------------------------------
3871da177e4SLinus Torvalds */
roundAndPackFloat64(struct roundingData * roundData,flag zSign,int16 zExp,bits64 zSig)388f148af25SRichard Purdie static float64 roundAndPackFloat64( struct roundingData *roundData, flag zSign, int16 zExp, bits64 zSig )
3891da177e4SLinus Torvalds {
3901da177e4SLinus Torvalds int8 roundingMode;
3911da177e4SLinus Torvalds flag roundNearestEven;
3921da177e4SLinus Torvalds int16 roundIncrement, roundBits;
3931da177e4SLinus Torvalds flag isTiny;
3941da177e4SLinus Torvalds
395f148af25SRichard Purdie roundingMode = roundData->mode;
3961da177e4SLinus Torvalds roundNearestEven = ( roundingMode == float_round_nearest_even );
3971da177e4SLinus Torvalds roundIncrement = 0x200;
3981da177e4SLinus Torvalds if ( ! roundNearestEven ) {
3991da177e4SLinus Torvalds if ( roundingMode == float_round_to_zero ) {
4001da177e4SLinus Torvalds roundIncrement = 0;
4011da177e4SLinus Torvalds }
4021da177e4SLinus Torvalds else {
4031da177e4SLinus Torvalds roundIncrement = 0x3FF;
4041da177e4SLinus Torvalds if ( zSign ) {
4051da177e4SLinus Torvalds if ( roundingMode == float_round_up ) roundIncrement = 0;
4061da177e4SLinus Torvalds }
4071da177e4SLinus Torvalds else {
4081da177e4SLinus Torvalds if ( roundingMode == float_round_down ) roundIncrement = 0;
4091da177e4SLinus Torvalds }
4101da177e4SLinus Torvalds }
4111da177e4SLinus Torvalds }
4121da177e4SLinus Torvalds roundBits = zSig & 0x3FF;
4131da177e4SLinus Torvalds if ( 0x7FD <= (bits16) zExp ) {
4141da177e4SLinus Torvalds if ( ( 0x7FD < zExp )
4151da177e4SLinus Torvalds || ( ( zExp == 0x7FD )
4161da177e4SLinus Torvalds && ( (sbits64) ( zSig + roundIncrement ) < 0 ) )
4171da177e4SLinus Torvalds ) {
4181da177e4SLinus Torvalds //register int lr = __builtin_return_address(0);
4191da177e4SLinus Torvalds //printk("roundAndPackFloat64 called from 0x%08x\n",lr);
420f148af25SRichard Purdie roundData->exception |= float_flag_overflow | float_flag_inexact;
4211da177e4SLinus Torvalds return packFloat64( zSign, 0x7FF, 0 ) - ( roundIncrement == 0 );
4221da177e4SLinus Torvalds }
4231da177e4SLinus Torvalds if ( zExp < 0 ) {
4241da177e4SLinus Torvalds isTiny =
4251da177e4SLinus Torvalds ( float_detect_tininess == float_tininess_before_rounding )
4261da177e4SLinus Torvalds || ( zExp < -1 )
4271da177e4SLinus Torvalds || ( zSig + roundIncrement < LIT64( 0x8000000000000000 ) );
4281da177e4SLinus Torvalds shift64RightJamming( zSig, - zExp, &zSig );
4291da177e4SLinus Torvalds zExp = 0;
4301da177e4SLinus Torvalds roundBits = zSig & 0x3FF;
431f148af25SRichard Purdie if ( isTiny && roundBits ) roundData->exception |= float_flag_underflow;
4321da177e4SLinus Torvalds }
4331da177e4SLinus Torvalds }
434f148af25SRichard Purdie if ( roundBits ) roundData->exception |= float_flag_inexact;
4351da177e4SLinus Torvalds zSig = ( zSig + roundIncrement )>>10;
4361da177e4SLinus Torvalds zSig &= ~ ( ( ( roundBits ^ 0x200 ) == 0 ) & roundNearestEven );
4371da177e4SLinus Torvalds if ( zSig == 0 ) zExp = 0;
4381da177e4SLinus Torvalds return packFloat64( zSign, zExp, zSig );
4391da177e4SLinus Torvalds
4401da177e4SLinus Torvalds }
4411da177e4SLinus Torvalds
4421da177e4SLinus Torvalds /*
4431da177e4SLinus Torvalds -------------------------------------------------------------------------------
4441da177e4SLinus Torvalds Takes an abstract floating-point value having sign `zSign', exponent `zExp',
4451da177e4SLinus Torvalds and significand `zSig', and returns the proper double-precision floating-
4461da177e4SLinus Torvalds point value corresponding to the abstract input. This routine is just like
4471da177e4SLinus Torvalds `roundAndPackFloat64' except that `zSig' does not have to be normalized in
4481da177e4SLinus Torvalds any way. In all cases, `zExp' must be 1 less than the ``true'' floating-
4491da177e4SLinus Torvalds point exponent.
4501da177e4SLinus Torvalds -------------------------------------------------------------------------------
4511da177e4SLinus Torvalds */
4521da177e4SLinus Torvalds static float64
normalizeRoundAndPackFloat64(struct roundingData * roundData,flag zSign,int16 zExp,bits64 zSig)453f148af25SRichard Purdie normalizeRoundAndPackFloat64( struct roundingData *roundData, flag zSign, int16 zExp, bits64 zSig )
4541da177e4SLinus Torvalds {
4551da177e4SLinus Torvalds int8 shiftCount;
4561da177e4SLinus Torvalds
4571da177e4SLinus Torvalds shiftCount = countLeadingZeros64( zSig ) - 1;
458f148af25SRichard Purdie return roundAndPackFloat64( roundData, zSign, zExp - shiftCount, zSig<<shiftCount );
4591da177e4SLinus Torvalds
4601da177e4SLinus Torvalds }
4611da177e4SLinus Torvalds
4621da177e4SLinus Torvalds #ifdef FLOATX80
4631da177e4SLinus Torvalds
4641da177e4SLinus Torvalds /*
4651da177e4SLinus Torvalds -------------------------------------------------------------------------------
4661da177e4SLinus Torvalds Returns the fraction bits of the extended double-precision floating-point
4671da177e4SLinus Torvalds value `a'.
4681da177e4SLinus Torvalds -------------------------------------------------------------------------------
4691da177e4SLinus Torvalds */
extractFloatx80Frac(floatx80 a)4701da177e4SLinus Torvalds INLINE bits64 extractFloatx80Frac( floatx80 a )
4711da177e4SLinus Torvalds {
4721da177e4SLinus Torvalds
4731da177e4SLinus Torvalds return a.low;
4741da177e4SLinus Torvalds
4751da177e4SLinus Torvalds }
4761da177e4SLinus Torvalds
4771da177e4SLinus Torvalds /*
4781da177e4SLinus Torvalds -------------------------------------------------------------------------------
4791da177e4SLinus Torvalds Returns the exponent bits of the extended double-precision floating-point
4801da177e4SLinus Torvalds value `a'.
4811da177e4SLinus Torvalds -------------------------------------------------------------------------------
4821da177e4SLinus Torvalds */
extractFloatx80Exp(floatx80 a)4831da177e4SLinus Torvalds INLINE int32 extractFloatx80Exp( floatx80 a )
4841da177e4SLinus Torvalds {
4851da177e4SLinus Torvalds
4861da177e4SLinus Torvalds return a.high & 0x7FFF;
4871da177e4SLinus Torvalds
4881da177e4SLinus Torvalds }
4891da177e4SLinus Torvalds
4901da177e4SLinus Torvalds /*
4911da177e4SLinus Torvalds -------------------------------------------------------------------------------
4921da177e4SLinus Torvalds Returns the sign bit of the extended double-precision floating-point value
4931da177e4SLinus Torvalds `a'.
4941da177e4SLinus Torvalds -------------------------------------------------------------------------------
4951da177e4SLinus Torvalds */
extractFloatx80Sign(floatx80 a)4961da177e4SLinus Torvalds INLINE flag extractFloatx80Sign( floatx80 a )
4971da177e4SLinus Torvalds {
4981da177e4SLinus Torvalds
4991da177e4SLinus Torvalds return a.high>>15;
5001da177e4SLinus Torvalds
5011da177e4SLinus Torvalds }
5021da177e4SLinus Torvalds
5031da177e4SLinus Torvalds /*
5041da177e4SLinus Torvalds -------------------------------------------------------------------------------
5051da177e4SLinus Torvalds Normalizes the subnormal extended double-precision floating-point value
5061da177e4SLinus Torvalds represented by the denormalized significand `aSig'. The normalized exponent
5071da177e4SLinus Torvalds and significand are stored at the locations pointed to by `zExpPtr' and
5081da177e4SLinus Torvalds `zSigPtr', respectively.
5091da177e4SLinus Torvalds -------------------------------------------------------------------------------
5101da177e4SLinus Torvalds */
5111da177e4SLinus Torvalds static void
normalizeFloatx80Subnormal(bits64 aSig,int32 * zExpPtr,bits64 * zSigPtr)5121da177e4SLinus Torvalds normalizeFloatx80Subnormal( bits64 aSig, int32 *zExpPtr, bits64 *zSigPtr )
5131da177e4SLinus Torvalds {
5141da177e4SLinus Torvalds int8 shiftCount;
5151da177e4SLinus Torvalds
5161da177e4SLinus Torvalds shiftCount = countLeadingZeros64( aSig );
5171da177e4SLinus Torvalds *zSigPtr = aSig<<shiftCount;
5181da177e4SLinus Torvalds *zExpPtr = 1 - shiftCount;
5191da177e4SLinus Torvalds
5201da177e4SLinus Torvalds }
5211da177e4SLinus Torvalds
5221da177e4SLinus Torvalds /*
5231da177e4SLinus Torvalds -------------------------------------------------------------------------------
5241da177e4SLinus Torvalds Packs the sign `zSign', exponent `zExp', and significand `zSig' into an
5251da177e4SLinus Torvalds extended double-precision floating-point value, returning the result.
5261da177e4SLinus Torvalds -------------------------------------------------------------------------------
5271da177e4SLinus Torvalds */
packFloatx80(flag zSign,int32 zExp,bits64 zSig)5281da177e4SLinus Torvalds INLINE floatx80 packFloatx80( flag zSign, int32 zExp, bits64 zSig )
5291da177e4SLinus Torvalds {
5301da177e4SLinus Torvalds floatx80 z;
5311da177e4SLinus Torvalds
5321da177e4SLinus Torvalds z.low = zSig;
5331da177e4SLinus Torvalds z.high = ( ( (bits16) zSign )<<15 ) + zExp;
53406c03cacSLennert Buytenhek z.__padding = 0;
5351da177e4SLinus Torvalds return z;
5361da177e4SLinus Torvalds
5371da177e4SLinus Torvalds }
5381da177e4SLinus Torvalds
5391da177e4SLinus Torvalds /*
5401da177e4SLinus Torvalds -------------------------------------------------------------------------------
5411da177e4SLinus Torvalds Takes an abstract floating-point value having sign `zSign', exponent `zExp',
5421da177e4SLinus Torvalds and extended significand formed by the concatenation of `zSig0' and `zSig1',
5431da177e4SLinus Torvalds and returns the proper extended double-precision floating-point value
5441da177e4SLinus Torvalds corresponding to the abstract input. Ordinarily, the abstract value is
5451da177e4SLinus Torvalds rounded and packed into the extended double-precision format, with the
5461da177e4SLinus Torvalds inexact exception raised if the abstract input cannot be represented
5471da177e4SLinus Torvalds exactly. If the abstract value is too large, however, the overflow and
5481da177e4SLinus Torvalds inexact exceptions are raised and an infinity or maximal finite value is
5491da177e4SLinus Torvalds returned. If the abstract value is too small, the input value is rounded to
5501da177e4SLinus Torvalds a subnormal number, and the underflow and inexact exceptions are raised if
5511da177e4SLinus Torvalds the abstract input cannot be represented exactly as a subnormal extended
5521da177e4SLinus Torvalds double-precision floating-point number.
5531da177e4SLinus Torvalds If `roundingPrecision' is 32 or 64, the result is rounded to the same
5541da177e4SLinus Torvalds number of bits as single or double precision, respectively. Otherwise, the
5551da177e4SLinus Torvalds result is rounded to the full precision of the extended double-precision
5561da177e4SLinus Torvalds format.
5571da177e4SLinus Torvalds The input significand must be normalized or smaller. If the input
5581da177e4SLinus Torvalds significand is not normalized, `zExp' must be 0; in that case, the result
5591da177e4SLinus Torvalds returned is a subnormal number, and it must not require rounding. The
5601da177e4SLinus Torvalds handling of underflow and overflow follows the IEC/IEEE Standard for Binary
5611da177e4SLinus Torvalds Floating-point Arithmetic.
5621da177e4SLinus Torvalds -------------------------------------------------------------------------------
5631da177e4SLinus Torvalds */
5641da177e4SLinus Torvalds static floatx80
roundAndPackFloatx80(struct roundingData * roundData,flag zSign,int32 zExp,bits64 zSig0,bits64 zSig1)5651da177e4SLinus Torvalds roundAndPackFloatx80(
566f148af25SRichard Purdie struct roundingData *roundData, flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1
5671da177e4SLinus Torvalds )
5681da177e4SLinus Torvalds {
569f148af25SRichard Purdie int8 roundingMode, roundingPrecision;
5701da177e4SLinus Torvalds flag roundNearestEven, increment, isTiny;
5711da177e4SLinus Torvalds int64 roundIncrement, roundMask, roundBits;
5721da177e4SLinus Torvalds
573f148af25SRichard Purdie roundingMode = roundData->mode;
574f148af25SRichard Purdie roundingPrecision = roundData->precision;
5751da177e4SLinus Torvalds roundNearestEven = ( roundingMode == float_round_nearest_even );
5761da177e4SLinus Torvalds if ( roundingPrecision == 80 ) goto precision80;
5771da177e4SLinus Torvalds if ( roundingPrecision == 64 ) {
5781da177e4SLinus Torvalds roundIncrement = LIT64( 0x0000000000000400 );
5791da177e4SLinus Torvalds roundMask = LIT64( 0x00000000000007FF );
5801da177e4SLinus Torvalds }
5811da177e4SLinus Torvalds else if ( roundingPrecision == 32 ) {
5821da177e4SLinus Torvalds roundIncrement = LIT64( 0x0000008000000000 );
5831da177e4SLinus Torvalds roundMask = LIT64( 0x000000FFFFFFFFFF );
5841da177e4SLinus Torvalds }
5851da177e4SLinus Torvalds else {
5861da177e4SLinus Torvalds goto precision80;
5871da177e4SLinus Torvalds }
5881da177e4SLinus Torvalds zSig0 |= ( zSig1 != 0 );
5891da177e4SLinus Torvalds if ( ! roundNearestEven ) {
5901da177e4SLinus Torvalds if ( roundingMode == float_round_to_zero ) {
5911da177e4SLinus Torvalds roundIncrement = 0;
5921da177e4SLinus Torvalds }
5931da177e4SLinus Torvalds else {
5941da177e4SLinus Torvalds roundIncrement = roundMask;
5951da177e4SLinus Torvalds if ( zSign ) {
5961da177e4SLinus Torvalds if ( roundingMode == float_round_up ) roundIncrement = 0;
5971da177e4SLinus Torvalds }
5981da177e4SLinus Torvalds else {
5991da177e4SLinus Torvalds if ( roundingMode == float_round_down ) roundIncrement = 0;
6001da177e4SLinus Torvalds }
6011da177e4SLinus Torvalds }
6021da177e4SLinus Torvalds }
6031da177e4SLinus Torvalds roundBits = zSig0 & roundMask;
6041da177e4SLinus Torvalds if ( 0x7FFD <= (bits32) ( zExp - 1 ) ) {
6051da177e4SLinus Torvalds if ( ( 0x7FFE < zExp )
6061da177e4SLinus Torvalds || ( ( zExp == 0x7FFE ) && ( zSig0 + roundIncrement < zSig0 ) )
6071da177e4SLinus Torvalds ) {
6081da177e4SLinus Torvalds goto overflow;
6091da177e4SLinus Torvalds }
6101da177e4SLinus Torvalds if ( zExp <= 0 ) {
6111da177e4SLinus Torvalds isTiny =
6121da177e4SLinus Torvalds ( float_detect_tininess == float_tininess_before_rounding )
6131da177e4SLinus Torvalds || ( zExp < 0 )
6141da177e4SLinus Torvalds || ( zSig0 <= zSig0 + roundIncrement );
6151da177e4SLinus Torvalds shift64RightJamming( zSig0, 1 - zExp, &zSig0 );
6161da177e4SLinus Torvalds zExp = 0;
6171da177e4SLinus Torvalds roundBits = zSig0 & roundMask;
618f148af25SRichard Purdie if ( isTiny && roundBits ) roundData->exception |= float_flag_underflow;
619f148af25SRichard Purdie if ( roundBits ) roundData->exception |= float_flag_inexact;
6201da177e4SLinus Torvalds zSig0 += roundIncrement;
6211da177e4SLinus Torvalds if ( (sbits64) zSig0 < 0 ) zExp = 1;
6221da177e4SLinus Torvalds roundIncrement = roundMask + 1;
6231da177e4SLinus Torvalds if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) {
6241da177e4SLinus Torvalds roundMask |= roundIncrement;
6251da177e4SLinus Torvalds }
6261da177e4SLinus Torvalds zSig0 &= ~ roundMask;
6271da177e4SLinus Torvalds return packFloatx80( zSign, zExp, zSig0 );
6281da177e4SLinus Torvalds }
6291da177e4SLinus Torvalds }
630f148af25SRichard Purdie if ( roundBits ) roundData->exception |= float_flag_inexact;
6311da177e4SLinus Torvalds zSig0 += roundIncrement;
6321da177e4SLinus Torvalds if ( zSig0 < roundIncrement ) {
6331da177e4SLinus Torvalds ++zExp;
6341da177e4SLinus Torvalds zSig0 = LIT64( 0x8000000000000000 );
6351da177e4SLinus Torvalds }
6361da177e4SLinus Torvalds roundIncrement = roundMask + 1;
6371da177e4SLinus Torvalds if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) {
6381da177e4SLinus Torvalds roundMask |= roundIncrement;
6391da177e4SLinus Torvalds }
6401da177e4SLinus Torvalds zSig0 &= ~ roundMask;
6411da177e4SLinus Torvalds if ( zSig0 == 0 ) zExp = 0;
6421da177e4SLinus Torvalds return packFloatx80( zSign, zExp, zSig0 );
6431da177e4SLinus Torvalds precision80:
6441da177e4SLinus Torvalds increment = ( (sbits64) zSig1 < 0 );
6451da177e4SLinus Torvalds if ( ! roundNearestEven ) {
6461da177e4SLinus Torvalds if ( roundingMode == float_round_to_zero ) {
6471da177e4SLinus Torvalds increment = 0;
6481da177e4SLinus Torvalds }
6491da177e4SLinus Torvalds else {
6501da177e4SLinus Torvalds if ( zSign ) {
6511da177e4SLinus Torvalds increment = ( roundingMode == float_round_down ) && zSig1;
6521da177e4SLinus Torvalds }
6531da177e4SLinus Torvalds else {
6541da177e4SLinus Torvalds increment = ( roundingMode == float_round_up ) && zSig1;
6551da177e4SLinus Torvalds }
6561da177e4SLinus Torvalds }
6571da177e4SLinus Torvalds }
6581da177e4SLinus Torvalds if ( 0x7FFD <= (bits32) ( zExp - 1 ) ) {
6591da177e4SLinus Torvalds if ( ( 0x7FFE < zExp )
6601da177e4SLinus Torvalds || ( ( zExp == 0x7FFE )
6611da177e4SLinus Torvalds && ( zSig0 == LIT64( 0xFFFFFFFFFFFFFFFF ) )
6621da177e4SLinus Torvalds && increment
6631da177e4SLinus Torvalds )
6641da177e4SLinus Torvalds ) {
6651da177e4SLinus Torvalds roundMask = 0;
6661da177e4SLinus Torvalds overflow:
667f148af25SRichard Purdie roundData->exception |= float_flag_overflow | float_flag_inexact;
6681da177e4SLinus Torvalds if ( ( roundingMode == float_round_to_zero )
6691da177e4SLinus Torvalds || ( zSign && ( roundingMode == float_round_up ) )
6701da177e4SLinus Torvalds || ( ! zSign && ( roundingMode == float_round_down ) )
6711da177e4SLinus Torvalds ) {
6721da177e4SLinus Torvalds return packFloatx80( zSign, 0x7FFE, ~ roundMask );
6731da177e4SLinus Torvalds }
6741da177e4SLinus Torvalds return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
6751da177e4SLinus Torvalds }
6761da177e4SLinus Torvalds if ( zExp <= 0 ) {
6771da177e4SLinus Torvalds isTiny =
6781da177e4SLinus Torvalds ( float_detect_tininess == float_tininess_before_rounding )
6791da177e4SLinus Torvalds || ( zExp < 0 )
6801da177e4SLinus Torvalds || ! increment
6811da177e4SLinus Torvalds || ( zSig0 < LIT64( 0xFFFFFFFFFFFFFFFF ) );
6821da177e4SLinus Torvalds shift64ExtraRightJamming( zSig0, zSig1, 1 - zExp, &zSig0, &zSig1 );
6831da177e4SLinus Torvalds zExp = 0;
684f148af25SRichard Purdie if ( isTiny && zSig1 ) roundData->exception |= float_flag_underflow;
685f148af25SRichard Purdie if ( zSig1 ) roundData->exception |= float_flag_inexact;
6861da177e4SLinus Torvalds if ( roundNearestEven ) {
6871da177e4SLinus Torvalds increment = ( (sbits64) zSig1 < 0 );
6881da177e4SLinus Torvalds }
6891da177e4SLinus Torvalds else {
6901da177e4SLinus Torvalds if ( zSign ) {
6911da177e4SLinus Torvalds increment = ( roundingMode == float_round_down ) && zSig1;
6921da177e4SLinus Torvalds }
6931da177e4SLinus Torvalds else {
6941da177e4SLinus Torvalds increment = ( roundingMode == float_round_up ) && zSig1;
6951da177e4SLinus Torvalds }
6961da177e4SLinus Torvalds }
6971da177e4SLinus Torvalds if ( increment ) {
6981da177e4SLinus Torvalds ++zSig0;
6991da177e4SLinus Torvalds zSig0 &= ~ ( ( zSig1 + zSig1 == 0 ) & roundNearestEven );
7001da177e4SLinus Torvalds if ( (sbits64) zSig0 < 0 ) zExp = 1;
7011da177e4SLinus Torvalds }
7021da177e4SLinus Torvalds return packFloatx80( zSign, zExp, zSig0 );
7031da177e4SLinus Torvalds }
7041da177e4SLinus Torvalds }
705f148af25SRichard Purdie if ( zSig1 ) roundData->exception |= float_flag_inexact;
7061da177e4SLinus Torvalds if ( increment ) {
7071da177e4SLinus Torvalds ++zSig0;
7081da177e4SLinus Torvalds if ( zSig0 == 0 ) {
7091da177e4SLinus Torvalds ++zExp;
7101da177e4SLinus Torvalds zSig0 = LIT64( 0x8000000000000000 );
7111da177e4SLinus Torvalds }
7121da177e4SLinus Torvalds else {
7131da177e4SLinus Torvalds zSig0 &= ~ ( ( zSig1 + zSig1 == 0 ) & roundNearestEven );
7141da177e4SLinus Torvalds }
7151da177e4SLinus Torvalds }
7161da177e4SLinus Torvalds else {
7171da177e4SLinus Torvalds if ( zSig0 == 0 ) zExp = 0;
7181da177e4SLinus Torvalds }
7191da177e4SLinus Torvalds
7201da177e4SLinus Torvalds return packFloatx80( zSign, zExp, zSig0 );
7211da177e4SLinus Torvalds }
7221da177e4SLinus Torvalds
7231da177e4SLinus Torvalds /*
7241da177e4SLinus Torvalds -------------------------------------------------------------------------------
7251da177e4SLinus Torvalds Takes an abstract floating-point value having sign `zSign', exponent
7261da177e4SLinus Torvalds `zExp', and significand formed by the concatenation of `zSig0' and `zSig1',
7271da177e4SLinus Torvalds and returns the proper extended double-precision floating-point value
7281da177e4SLinus Torvalds corresponding to the abstract input. This routine is just like
7291da177e4SLinus Torvalds `roundAndPackFloatx80' except that the input significand does not have to be
7301da177e4SLinus Torvalds normalized.
7311da177e4SLinus Torvalds -------------------------------------------------------------------------------
7321da177e4SLinus Torvalds */
7331da177e4SLinus Torvalds static floatx80
normalizeRoundAndPackFloatx80(struct roundingData * roundData,flag zSign,int32 zExp,bits64 zSig0,bits64 zSig1)7341da177e4SLinus Torvalds normalizeRoundAndPackFloatx80(
735f148af25SRichard Purdie struct roundingData *roundData, flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1
7361da177e4SLinus Torvalds )
7371da177e4SLinus Torvalds {
7381da177e4SLinus Torvalds int8 shiftCount;
7391da177e4SLinus Torvalds
7401da177e4SLinus Torvalds if ( zSig0 == 0 ) {
7411da177e4SLinus Torvalds zSig0 = zSig1;
7421da177e4SLinus Torvalds zSig1 = 0;
7431da177e4SLinus Torvalds zExp -= 64;
7441da177e4SLinus Torvalds }
7451da177e4SLinus Torvalds shiftCount = countLeadingZeros64( zSig0 );
7461da177e4SLinus Torvalds shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 );
7471da177e4SLinus Torvalds zExp -= shiftCount;
7481da177e4SLinus Torvalds return
749f148af25SRichard Purdie roundAndPackFloatx80( roundData, zSign, zExp, zSig0, zSig1 );
7501da177e4SLinus Torvalds
7511da177e4SLinus Torvalds }
7521da177e4SLinus Torvalds
7531da177e4SLinus Torvalds #endif
7541da177e4SLinus Torvalds
7551da177e4SLinus Torvalds /*
7561da177e4SLinus Torvalds -------------------------------------------------------------------------------
7571da177e4SLinus Torvalds Returns the result of converting the 32-bit two's complement integer `a' to
7581da177e4SLinus Torvalds the single-precision floating-point format. The conversion is performed
7591da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
7601da177e4SLinus Torvalds -------------------------------------------------------------------------------
7611da177e4SLinus Torvalds */
int32_to_float32(struct roundingData * roundData,int32 a)762f148af25SRichard Purdie float32 int32_to_float32(struct roundingData *roundData, int32 a)
7631da177e4SLinus Torvalds {
7641da177e4SLinus Torvalds flag zSign;
7651da177e4SLinus Torvalds
7661da177e4SLinus Torvalds if ( a == 0 ) return 0;
7671da177e4SLinus Torvalds if ( a == 0x80000000 ) return packFloat32( 1, 0x9E, 0 );
7681da177e4SLinus Torvalds zSign = ( a < 0 );
769f148af25SRichard Purdie return normalizeRoundAndPackFloat32( roundData, zSign, 0x9C, zSign ? - a : a );
7701da177e4SLinus Torvalds
7711da177e4SLinus Torvalds }
7721da177e4SLinus Torvalds
7731da177e4SLinus Torvalds /*
7741da177e4SLinus Torvalds -------------------------------------------------------------------------------
7751da177e4SLinus Torvalds Returns the result of converting the 32-bit two's complement integer `a' to
7761da177e4SLinus Torvalds the double-precision floating-point format. The conversion is performed
7771da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
7781da177e4SLinus Torvalds -------------------------------------------------------------------------------
7791da177e4SLinus Torvalds */
int32_to_float64(int32 a)7801da177e4SLinus Torvalds float64 int32_to_float64( int32 a )
7811da177e4SLinus Torvalds {
7821da177e4SLinus Torvalds flag aSign;
7831da177e4SLinus Torvalds uint32 absA;
7841da177e4SLinus Torvalds int8 shiftCount;
7851da177e4SLinus Torvalds bits64 zSig;
7861da177e4SLinus Torvalds
7871da177e4SLinus Torvalds if ( a == 0 ) return 0;
7881da177e4SLinus Torvalds aSign = ( a < 0 );
7891da177e4SLinus Torvalds absA = aSign ? - a : a;
7901da177e4SLinus Torvalds shiftCount = countLeadingZeros32( absA ) + 21;
7911da177e4SLinus Torvalds zSig = absA;
7921da177e4SLinus Torvalds return packFloat64( aSign, 0x432 - shiftCount, zSig<<shiftCount );
7931da177e4SLinus Torvalds
7941da177e4SLinus Torvalds }
7951da177e4SLinus Torvalds
7961da177e4SLinus Torvalds #ifdef FLOATX80
7971da177e4SLinus Torvalds
7981da177e4SLinus Torvalds /*
7991da177e4SLinus Torvalds -------------------------------------------------------------------------------
8001da177e4SLinus Torvalds Returns the result of converting the 32-bit two's complement integer `a'
8011da177e4SLinus Torvalds to the extended double-precision floating-point format. The conversion
8021da177e4SLinus Torvalds is performed according to the IEC/IEEE Standard for Binary Floating-point
8031da177e4SLinus Torvalds Arithmetic.
8041da177e4SLinus Torvalds -------------------------------------------------------------------------------
8051da177e4SLinus Torvalds */
int32_to_floatx80(int32 a)8061da177e4SLinus Torvalds floatx80 int32_to_floatx80( int32 a )
8071da177e4SLinus Torvalds {
8081da177e4SLinus Torvalds flag zSign;
8091da177e4SLinus Torvalds uint32 absA;
8101da177e4SLinus Torvalds int8 shiftCount;
8111da177e4SLinus Torvalds bits64 zSig;
8121da177e4SLinus Torvalds
8131da177e4SLinus Torvalds if ( a == 0 ) return packFloatx80( 0, 0, 0 );
8141da177e4SLinus Torvalds zSign = ( a < 0 );
8151da177e4SLinus Torvalds absA = zSign ? - a : a;
8161da177e4SLinus Torvalds shiftCount = countLeadingZeros32( absA ) + 32;
8171da177e4SLinus Torvalds zSig = absA;
8181da177e4SLinus Torvalds return packFloatx80( zSign, 0x403E - shiftCount, zSig<<shiftCount );
8191da177e4SLinus Torvalds
8201da177e4SLinus Torvalds }
8211da177e4SLinus Torvalds
8221da177e4SLinus Torvalds #endif
8231da177e4SLinus Torvalds
8241da177e4SLinus Torvalds /*
8251da177e4SLinus Torvalds -------------------------------------------------------------------------------
8261da177e4SLinus Torvalds Returns the result of converting the single-precision floating-point value
8271da177e4SLinus Torvalds `a' to the 32-bit two's complement integer format. The conversion is
8281da177e4SLinus Torvalds performed according to the IEC/IEEE Standard for Binary Floating-point
8291da177e4SLinus Torvalds Arithmetic---which means in particular that the conversion is rounded
8301da177e4SLinus Torvalds according to the current rounding mode. If `a' is a NaN, the largest
8311da177e4SLinus Torvalds positive integer is returned. Otherwise, if the conversion overflows, the
8321da177e4SLinus Torvalds largest integer with the same sign as `a' is returned.
8331da177e4SLinus Torvalds -------------------------------------------------------------------------------
8341da177e4SLinus Torvalds */
float32_to_int32(struct roundingData * roundData,float32 a)835f148af25SRichard Purdie int32 float32_to_int32( struct roundingData *roundData, float32 a )
8361da177e4SLinus Torvalds {
8371da177e4SLinus Torvalds flag aSign;
8381da177e4SLinus Torvalds int16 aExp, shiftCount;
8391da177e4SLinus Torvalds bits32 aSig;
8401da177e4SLinus Torvalds bits64 zSig;
8411da177e4SLinus Torvalds
8421da177e4SLinus Torvalds aSig = extractFloat32Frac( a );
8431da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
8441da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
8451da177e4SLinus Torvalds if ( ( aExp == 0x7FF ) && aSig ) aSign = 0;
8461da177e4SLinus Torvalds if ( aExp ) aSig |= 0x00800000;
8471da177e4SLinus Torvalds shiftCount = 0xAF - aExp;
8481da177e4SLinus Torvalds zSig = aSig;
8491da177e4SLinus Torvalds zSig <<= 32;
8501da177e4SLinus Torvalds if ( 0 < shiftCount ) shift64RightJamming( zSig, shiftCount, &zSig );
851f148af25SRichard Purdie return roundAndPackInt32( roundData, aSign, zSig );
8521da177e4SLinus Torvalds
8531da177e4SLinus Torvalds }
8541da177e4SLinus Torvalds
8551da177e4SLinus Torvalds /*
8561da177e4SLinus Torvalds -------------------------------------------------------------------------------
8571da177e4SLinus Torvalds Returns the result of converting the single-precision floating-point value
8581da177e4SLinus Torvalds `a' to the 32-bit two's complement integer format. The conversion is
8591da177e4SLinus Torvalds performed according to the IEC/IEEE Standard for Binary Floating-point
8601da177e4SLinus Torvalds Arithmetic, except that the conversion is always rounded toward zero. If
8611da177e4SLinus Torvalds `a' is a NaN, the largest positive integer is returned. Otherwise, if the
8621da177e4SLinus Torvalds conversion overflows, the largest integer with the same sign as `a' is
8631da177e4SLinus Torvalds returned.
8641da177e4SLinus Torvalds -------------------------------------------------------------------------------
8651da177e4SLinus Torvalds */
float32_to_int32_round_to_zero(float32 a)8661da177e4SLinus Torvalds int32 float32_to_int32_round_to_zero( float32 a )
8671da177e4SLinus Torvalds {
8681da177e4SLinus Torvalds flag aSign;
8691da177e4SLinus Torvalds int16 aExp, shiftCount;
8701da177e4SLinus Torvalds bits32 aSig;
8711da177e4SLinus Torvalds int32 z;
8721da177e4SLinus Torvalds
8731da177e4SLinus Torvalds aSig = extractFloat32Frac( a );
8741da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
8751da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
8761da177e4SLinus Torvalds shiftCount = aExp - 0x9E;
8771da177e4SLinus Torvalds if ( 0 <= shiftCount ) {
8781da177e4SLinus Torvalds if ( a == 0xCF000000 ) return 0x80000000;
8791da177e4SLinus Torvalds float_raise( float_flag_invalid );
8801da177e4SLinus Torvalds if ( ! aSign || ( ( aExp == 0xFF ) && aSig ) ) return 0x7FFFFFFF;
8811da177e4SLinus Torvalds return 0x80000000;
8821da177e4SLinus Torvalds }
8831da177e4SLinus Torvalds else if ( aExp <= 0x7E ) {
884f148af25SRichard Purdie if ( aExp | aSig ) float_raise( float_flag_inexact );
8851da177e4SLinus Torvalds return 0;
8861da177e4SLinus Torvalds }
8871da177e4SLinus Torvalds aSig = ( aSig | 0x00800000 )<<8;
8881da177e4SLinus Torvalds z = aSig>>( - shiftCount );
8891da177e4SLinus Torvalds if ( (bits32) ( aSig<<( shiftCount & 31 ) ) ) {
890f148af25SRichard Purdie float_raise( float_flag_inexact );
8911da177e4SLinus Torvalds }
8921da177e4SLinus Torvalds return aSign ? - z : z;
8931da177e4SLinus Torvalds
8941da177e4SLinus Torvalds }
8951da177e4SLinus Torvalds
8961da177e4SLinus Torvalds /*
8971da177e4SLinus Torvalds -------------------------------------------------------------------------------
8981da177e4SLinus Torvalds Returns the result of converting the single-precision floating-point value
8991da177e4SLinus Torvalds `a' to the double-precision floating-point format. The conversion is
9001da177e4SLinus Torvalds performed according to the IEC/IEEE Standard for Binary Floating-point
9011da177e4SLinus Torvalds Arithmetic.
9021da177e4SLinus Torvalds -------------------------------------------------------------------------------
9031da177e4SLinus Torvalds */
float32_to_float64(float32 a)9041da177e4SLinus Torvalds float64 float32_to_float64( float32 a )
9051da177e4SLinus Torvalds {
9061da177e4SLinus Torvalds flag aSign;
9071da177e4SLinus Torvalds int16 aExp;
9081da177e4SLinus Torvalds bits32 aSig;
9091da177e4SLinus Torvalds
9101da177e4SLinus Torvalds aSig = extractFloat32Frac( a );
9111da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
9121da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
9131da177e4SLinus Torvalds if ( aExp == 0xFF ) {
9141da177e4SLinus Torvalds if ( aSig ) return commonNaNToFloat64( float32ToCommonNaN( a ) );
9151da177e4SLinus Torvalds return packFloat64( aSign, 0x7FF, 0 );
9161da177e4SLinus Torvalds }
9171da177e4SLinus Torvalds if ( aExp == 0 ) {
9181da177e4SLinus Torvalds if ( aSig == 0 ) return packFloat64( aSign, 0, 0 );
9191da177e4SLinus Torvalds normalizeFloat32Subnormal( aSig, &aExp, &aSig );
9201da177e4SLinus Torvalds --aExp;
9211da177e4SLinus Torvalds }
9221da177e4SLinus Torvalds return packFloat64( aSign, aExp + 0x380, ( (bits64) aSig )<<29 );
9231da177e4SLinus Torvalds
9241da177e4SLinus Torvalds }
9251da177e4SLinus Torvalds
9261da177e4SLinus Torvalds #ifdef FLOATX80
9271da177e4SLinus Torvalds
9281da177e4SLinus Torvalds /*
9291da177e4SLinus Torvalds -------------------------------------------------------------------------------
9301da177e4SLinus Torvalds Returns the result of converting the single-precision floating-point value
9311da177e4SLinus Torvalds `a' to the extended double-precision floating-point format. The conversion
9321da177e4SLinus Torvalds is performed according to the IEC/IEEE Standard for Binary Floating-point
9331da177e4SLinus Torvalds Arithmetic.
9341da177e4SLinus Torvalds -------------------------------------------------------------------------------
9351da177e4SLinus Torvalds */
float32_to_floatx80(float32 a)9361da177e4SLinus Torvalds floatx80 float32_to_floatx80( float32 a )
9371da177e4SLinus Torvalds {
9381da177e4SLinus Torvalds flag aSign;
9391da177e4SLinus Torvalds int16 aExp;
9401da177e4SLinus Torvalds bits32 aSig;
9411da177e4SLinus Torvalds
9421da177e4SLinus Torvalds aSig = extractFloat32Frac( a );
9431da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
9441da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
9451da177e4SLinus Torvalds if ( aExp == 0xFF ) {
9461da177e4SLinus Torvalds if ( aSig ) return commonNaNToFloatx80( float32ToCommonNaN( a ) );
9471da177e4SLinus Torvalds return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
9481da177e4SLinus Torvalds }
9491da177e4SLinus Torvalds if ( aExp == 0 ) {
9501da177e4SLinus Torvalds if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 );
9511da177e4SLinus Torvalds normalizeFloat32Subnormal( aSig, &aExp, &aSig );
9521da177e4SLinus Torvalds }
9531da177e4SLinus Torvalds aSig |= 0x00800000;
9541da177e4SLinus Torvalds return packFloatx80( aSign, aExp + 0x3F80, ( (bits64) aSig )<<40 );
9551da177e4SLinus Torvalds
9561da177e4SLinus Torvalds }
9571da177e4SLinus Torvalds
9581da177e4SLinus Torvalds #endif
9591da177e4SLinus Torvalds
9601da177e4SLinus Torvalds /*
9611da177e4SLinus Torvalds -------------------------------------------------------------------------------
9621da177e4SLinus Torvalds Rounds the single-precision floating-point value `a' to an integer, and
9631da177e4SLinus Torvalds returns the result as a single-precision floating-point value. The
9641da177e4SLinus Torvalds operation is performed according to the IEC/IEEE Standard for Binary
9651da177e4SLinus Torvalds Floating-point Arithmetic.
9661da177e4SLinus Torvalds -------------------------------------------------------------------------------
9671da177e4SLinus Torvalds */
float32_round_to_int(struct roundingData * roundData,float32 a)968f148af25SRichard Purdie float32 float32_round_to_int( struct roundingData *roundData, float32 a )
9691da177e4SLinus Torvalds {
9701da177e4SLinus Torvalds flag aSign;
9711da177e4SLinus Torvalds int16 aExp;
9721da177e4SLinus Torvalds bits32 lastBitMask, roundBitsMask;
9731da177e4SLinus Torvalds int8 roundingMode;
9741da177e4SLinus Torvalds float32 z;
9751da177e4SLinus Torvalds
9761da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
9771da177e4SLinus Torvalds if ( 0x96 <= aExp ) {
9781da177e4SLinus Torvalds if ( ( aExp == 0xFF ) && extractFloat32Frac( a ) ) {
9791da177e4SLinus Torvalds return propagateFloat32NaN( a, a );
9801da177e4SLinus Torvalds }
9811da177e4SLinus Torvalds return a;
9821da177e4SLinus Torvalds }
983f148af25SRichard Purdie roundingMode = roundData->mode;
9841da177e4SLinus Torvalds if ( aExp <= 0x7E ) {
9851da177e4SLinus Torvalds if ( (bits32) ( a<<1 ) == 0 ) return a;
986f148af25SRichard Purdie roundData->exception |= float_flag_inexact;
9871da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
988f148af25SRichard Purdie switch ( roundingMode ) {
9891da177e4SLinus Torvalds case float_round_nearest_even:
9901da177e4SLinus Torvalds if ( ( aExp == 0x7E ) && extractFloat32Frac( a ) ) {
9911da177e4SLinus Torvalds return packFloat32( aSign, 0x7F, 0 );
9921da177e4SLinus Torvalds }
9931da177e4SLinus Torvalds break;
9941da177e4SLinus Torvalds case float_round_down:
9951da177e4SLinus Torvalds return aSign ? 0xBF800000 : 0;
9961da177e4SLinus Torvalds case float_round_up:
9971da177e4SLinus Torvalds return aSign ? 0x80000000 : 0x3F800000;
9981da177e4SLinus Torvalds }
9991da177e4SLinus Torvalds return packFloat32( aSign, 0, 0 );
10001da177e4SLinus Torvalds }
10011da177e4SLinus Torvalds lastBitMask = 1;
10021da177e4SLinus Torvalds lastBitMask <<= 0x96 - aExp;
10031da177e4SLinus Torvalds roundBitsMask = lastBitMask - 1;
10041da177e4SLinus Torvalds z = a;
10051da177e4SLinus Torvalds if ( roundingMode == float_round_nearest_even ) {
10061da177e4SLinus Torvalds z += lastBitMask>>1;
10071da177e4SLinus Torvalds if ( ( z & roundBitsMask ) == 0 ) z &= ~ lastBitMask;
10081da177e4SLinus Torvalds }
10091da177e4SLinus Torvalds else if ( roundingMode != float_round_to_zero ) {
10101da177e4SLinus Torvalds if ( extractFloat32Sign( z ) ^ ( roundingMode == float_round_up ) ) {
10111da177e4SLinus Torvalds z += roundBitsMask;
10121da177e4SLinus Torvalds }
10131da177e4SLinus Torvalds }
10141da177e4SLinus Torvalds z &= ~ roundBitsMask;
1015f148af25SRichard Purdie if ( z != a ) roundData->exception |= float_flag_inexact;
10161da177e4SLinus Torvalds return z;
10171da177e4SLinus Torvalds
10181da177e4SLinus Torvalds }
10191da177e4SLinus Torvalds
10201da177e4SLinus Torvalds /*
10211da177e4SLinus Torvalds -------------------------------------------------------------------------------
10221da177e4SLinus Torvalds Returns the result of adding the absolute values of the single-precision
10231da177e4SLinus Torvalds floating-point values `a' and `b'. If `zSign' is true, the sum is negated
10241da177e4SLinus Torvalds before being returned. `zSign' is ignored if the result is a NaN. The
10251da177e4SLinus Torvalds addition is performed according to the IEC/IEEE Standard for Binary
10261da177e4SLinus Torvalds Floating-point Arithmetic.
10271da177e4SLinus Torvalds -------------------------------------------------------------------------------
10281da177e4SLinus Torvalds */
addFloat32Sigs(struct roundingData * roundData,float32 a,float32 b,flag zSign)1029f148af25SRichard Purdie static float32 addFloat32Sigs( struct roundingData *roundData, float32 a, float32 b, flag zSign )
10301da177e4SLinus Torvalds {
10311da177e4SLinus Torvalds int16 aExp, bExp, zExp;
10321da177e4SLinus Torvalds bits32 aSig, bSig, zSig;
10331da177e4SLinus Torvalds int16 expDiff;
10341da177e4SLinus Torvalds
10351da177e4SLinus Torvalds aSig = extractFloat32Frac( a );
10361da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
10371da177e4SLinus Torvalds bSig = extractFloat32Frac( b );
10381da177e4SLinus Torvalds bExp = extractFloat32Exp( b );
10391da177e4SLinus Torvalds expDiff = aExp - bExp;
10401da177e4SLinus Torvalds aSig <<= 6;
10411da177e4SLinus Torvalds bSig <<= 6;
10421da177e4SLinus Torvalds if ( 0 < expDiff ) {
10431da177e4SLinus Torvalds if ( aExp == 0xFF ) {
10441da177e4SLinus Torvalds if ( aSig ) return propagateFloat32NaN( a, b );
10451da177e4SLinus Torvalds return a;
10461da177e4SLinus Torvalds }
10471da177e4SLinus Torvalds if ( bExp == 0 ) {
10481da177e4SLinus Torvalds --expDiff;
10491da177e4SLinus Torvalds }
10501da177e4SLinus Torvalds else {
10511da177e4SLinus Torvalds bSig |= 0x20000000;
10521da177e4SLinus Torvalds }
10531da177e4SLinus Torvalds shift32RightJamming( bSig, expDiff, &bSig );
10541da177e4SLinus Torvalds zExp = aExp;
10551da177e4SLinus Torvalds }
10561da177e4SLinus Torvalds else if ( expDiff < 0 ) {
10571da177e4SLinus Torvalds if ( bExp == 0xFF ) {
10581da177e4SLinus Torvalds if ( bSig ) return propagateFloat32NaN( a, b );
10591da177e4SLinus Torvalds return packFloat32( zSign, 0xFF, 0 );
10601da177e4SLinus Torvalds }
10611da177e4SLinus Torvalds if ( aExp == 0 ) {
10621da177e4SLinus Torvalds ++expDiff;
10631da177e4SLinus Torvalds }
10641da177e4SLinus Torvalds else {
10651da177e4SLinus Torvalds aSig |= 0x20000000;
10661da177e4SLinus Torvalds }
10671da177e4SLinus Torvalds shift32RightJamming( aSig, - expDiff, &aSig );
10681da177e4SLinus Torvalds zExp = bExp;
10691da177e4SLinus Torvalds }
10701da177e4SLinus Torvalds else {
10711da177e4SLinus Torvalds if ( aExp == 0xFF ) {
10721da177e4SLinus Torvalds if ( aSig | bSig ) return propagateFloat32NaN( a, b );
10731da177e4SLinus Torvalds return a;
10741da177e4SLinus Torvalds }
10751da177e4SLinus Torvalds if ( aExp == 0 ) return packFloat32( zSign, 0, ( aSig + bSig )>>6 );
10761da177e4SLinus Torvalds zSig = 0x40000000 + aSig + bSig;
10771da177e4SLinus Torvalds zExp = aExp;
10781da177e4SLinus Torvalds goto roundAndPack;
10791da177e4SLinus Torvalds }
10801da177e4SLinus Torvalds aSig |= 0x20000000;
10811da177e4SLinus Torvalds zSig = ( aSig + bSig )<<1;
10821da177e4SLinus Torvalds --zExp;
10831da177e4SLinus Torvalds if ( (sbits32) zSig < 0 ) {
10841da177e4SLinus Torvalds zSig = aSig + bSig;
10851da177e4SLinus Torvalds ++zExp;
10861da177e4SLinus Torvalds }
10871da177e4SLinus Torvalds roundAndPack:
1088f148af25SRichard Purdie return roundAndPackFloat32( roundData, zSign, zExp, zSig );
10891da177e4SLinus Torvalds
10901da177e4SLinus Torvalds }
10911da177e4SLinus Torvalds
10921da177e4SLinus Torvalds /*
10931da177e4SLinus Torvalds -------------------------------------------------------------------------------
10941da177e4SLinus Torvalds Returns the result of subtracting the absolute values of the single-
10951da177e4SLinus Torvalds precision floating-point values `a' and `b'. If `zSign' is true, the
10961da177e4SLinus Torvalds difference is negated before being returned. `zSign' is ignored if the
10971da177e4SLinus Torvalds result is a NaN. The subtraction is performed according to the IEC/IEEE
10981da177e4SLinus Torvalds Standard for Binary Floating-point Arithmetic.
10991da177e4SLinus Torvalds -------------------------------------------------------------------------------
11001da177e4SLinus Torvalds */
subFloat32Sigs(struct roundingData * roundData,float32 a,float32 b,flag zSign)1101f148af25SRichard Purdie static float32 subFloat32Sigs( struct roundingData *roundData, float32 a, float32 b, flag zSign )
11021da177e4SLinus Torvalds {
11031da177e4SLinus Torvalds int16 aExp, bExp, zExp;
11041da177e4SLinus Torvalds bits32 aSig, bSig, zSig;
11051da177e4SLinus Torvalds int16 expDiff;
11061da177e4SLinus Torvalds
11071da177e4SLinus Torvalds aSig = extractFloat32Frac( a );
11081da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
11091da177e4SLinus Torvalds bSig = extractFloat32Frac( b );
11101da177e4SLinus Torvalds bExp = extractFloat32Exp( b );
11111da177e4SLinus Torvalds expDiff = aExp - bExp;
11121da177e4SLinus Torvalds aSig <<= 7;
11131da177e4SLinus Torvalds bSig <<= 7;
11141da177e4SLinus Torvalds if ( 0 < expDiff ) goto aExpBigger;
11151da177e4SLinus Torvalds if ( expDiff < 0 ) goto bExpBigger;
11161da177e4SLinus Torvalds if ( aExp == 0xFF ) {
11171da177e4SLinus Torvalds if ( aSig | bSig ) return propagateFloat32NaN( a, b );
1118f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
11191da177e4SLinus Torvalds return float32_default_nan;
11201da177e4SLinus Torvalds }
11211da177e4SLinus Torvalds if ( aExp == 0 ) {
11221da177e4SLinus Torvalds aExp = 1;
11231da177e4SLinus Torvalds bExp = 1;
11241da177e4SLinus Torvalds }
11251da177e4SLinus Torvalds if ( bSig < aSig ) goto aBigger;
11261da177e4SLinus Torvalds if ( aSig < bSig ) goto bBigger;
1127f148af25SRichard Purdie return packFloat32( roundData->mode == float_round_down, 0, 0 );
11281da177e4SLinus Torvalds bExpBigger:
11291da177e4SLinus Torvalds if ( bExp == 0xFF ) {
11301da177e4SLinus Torvalds if ( bSig ) return propagateFloat32NaN( a, b );
11311da177e4SLinus Torvalds return packFloat32( zSign ^ 1, 0xFF, 0 );
11321da177e4SLinus Torvalds }
11331da177e4SLinus Torvalds if ( aExp == 0 ) {
11341da177e4SLinus Torvalds ++expDiff;
11351da177e4SLinus Torvalds }
11361da177e4SLinus Torvalds else {
11371da177e4SLinus Torvalds aSig |= 0x40000000;
11381da177e4SLinus Torvalds }
11391da177e4SLinus Torvalds shift32RightJamming( aSig, - expDiff, &aSig );
11401da177e4SLinus Torvalds bSig |= 0x40000000;
11411da177e4SLinus Torvalds bBigger:
11421da177e4SLinus Torvalds zSig = bSig - aSig;
11431da177e4SLinus Torvalds zExp = bExp;
11441da177e4SLinus Torvalds zSign ^= 1;
11451da177e4SLinus Torvalds goto normalizeRoundAndPack;
11461da177e4SLinus Torvalds aExpBigger:
11471da177e4SLinus Torvalds if ( aExp == 0xFF ) {
11481da177e4SLinus Torvalds if ( aSig ) return propagateFloat32NaN( a, b );
11491da177e4SLinus Torvalds return a;
11501da177e4SLinus Torvalds }
11511da177e4SLinus Torvalds if ( bExp == 0 ) {
11521da177e4SLinus Torvalds --expDiff;
11531da177e4SLinus Torvalds }
11541da177e4SLinus Torvalds else {
11551da177e4SLinus Torvalds bSig |= 0x40000000;
11561da177e4SLinus Torvalds }
11571da177e4SLinus Torvalds shift32RightJamming( bSig, expDiff, &bSig );
11581da177e4SLinus Torvalds aSig |= 0x40000000;
11591da177e4SLinus Torvalds aBigger:
11601da177e4SLinus Torvalds zSig = aSig - bSig;
11611da177e4SLinus Torvalds zExp = aExp;
11621da177e4SLinus Torvalds normalizeRoundAndPack:
11631da177e4SLinus Torvalds --zExp;
1164f148af25SRichard Purdie return normalizeRoundAndPackFloat32( roundData, zSign, zExp, zSig );
11651da177e4SLinus Torvalds
11661da177e4SLinus Torvalds }
11671da177e4SLinus Torvalds
11681da177e4SLinus Torvalds /*
11691da177e4SLinus Torvalds -------------------------------------------------------------------------------
11701da177e4SLinus Torvalds Returns the result of adding the single-precision floating-point values `a'
11711da177e4SLinus Torvalds and `b'. The operation is performed according to the IEC/IEEE Standard for
11721da177e4SLinus Torvalds Binary Floating-point Arithmetic.
11731da177e4SLinus Torvalds -------------------------------------------------------------------------------
11741da177e4SLinus Torvalds */
float32_add(struct roundingData * roundData,float32 a,float32 b)1175f148af25SRichard Purdie float32 float32_add( struct roundingData *roundData, float32 a, float32 b )
11761da177e4SLinus Torvalds {
11771da177e4SLinus Torvalds flag aSign, bSign;
11781da177e4SLinus Torvalds
11791da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
11801da177e4SLinus Torvalds bSign = extractFloat32Sign( b );
11811da177e4SLinus Torvalds if ( aSign == bSign ) {
1182f148af25SRichard Purdie return addFloat32Sigs( roundData, a, b, aSign );
11831da177e4SLinus Torvalds }
11841da177e4SLinus Torvalds else {
1185f148af25SRichard Purdie return subFloat32Sigs( roundData, a, b, aSign );
11861da177e4SLinus Torvalds }
11871da177e4SLinus Torvalds
11881da177e4SLinus Torvalds }
11891da177e4SLinus Torvalds
11901da177e4SLinus Torvalds /*
11911da177e4SLinus Torvalds -------------------------------------------------------------------------------
11921da177e4SLinus Torvalds Returns the result of subtracting the single-precision floating-point values
11931da177e4SLinus Torvalds `a' and `b'. The operation is performed according to the IEC/IEEE Standard
11941da177e4SLinus Torvalds for Binary Floating-point Arithmetic.
11951da177e4SLinus Torvalds -------------------------------------------------------------------------------
11961da177e4SLinus Torvalds */
float32_sub(struct roundingData * roundData,float32 a,float32 b)1197f148af25SRichard Purdie float32 float32_sub( struct roundingData *roundData, float32 a, float32 b )
11981da177e4SLinus Torvalds {
11991da177e4SLinus Torvalds flag aSign, bSign;
12001da177e4SLinus Torvalds
12011da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
12021da177e4SLinus Torvalds bSign = extractFloat32Sign( b );
12031da177e4SLinus Torvalds if ( aSign == bSign ) {
1204f148af25SRichard Purdie return subFloat32Sigs( roundData, a, b, aSign );
12051da177e4SLinus Torvalds }
12061da177e4SLinus Torvalds else {
1207f148af25SRichard Purdie return addFloat32Sigs( roundData, a, b, aSign );
12081da177e4SLinus Torvalds }
12091da177e4SLinus Torvalds
12101da177e4SLinus Torvalds }
12111da177e4SLinus Torvalds
12121da177e4SLinus Torvalds /*
12131da177e4SLinus Torvalds -------------------------------------------------------------------------------
12141da177e4SLinus Torvalds Returns the result of multiplying the single-precision floating-point values
12151da177e4SLinus Torvalds `a' and `b'. The operation is performed according to the IEC/IEEE Standard
12161da177e4SLinus Torvalds for Binary Floating-point Arithmetic.
12171da177e4SLinus Torvalds -------------------------------------------------------------------------------
12181da177e4SLinus Torvalds */
float32_mul(struct roundingData * roundData,float32 a,float32 b)1219f148af25SRichard Purdie float32 float32_mul( struct roundingData *roundData, float32 a, float32 b )
12201da177e4SLinus Torvalds {
12211da177e4SLinus Torvalds flag aSign, bSign, zSign;
12221da177e4SLinus Torvalds int16 aExp, bExp, zExp;
12231da177e4SLinus Torvalds bits32 aSig, bSig;
12241da177e4SLinus Torvalds bits64 zSig64;
12251da177e4SLinus Torvalds bits32 zSig;
12261da177e4SLinus Torvalds
12271da177e4SLinus Torvalds aSig = extractFloat32Frac( a );
12281da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
12291da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
12301da177e4SLinus Torvalds bSig = extractFloat32Frac( b );
12311da177e4SLinus Torvalds bExp = extractFloat32Exp( b );
12321da177e4SLinus Torvalds bSign = extractFloat32Sign( b );
12331da177e4SLinus Torvalds zSign = aSign ^ bSign;
12341da177e4SLinus Torvalds if ( aExp == 0xFF ) {
12351da177e4SLinus Torvalds if ( aSig || ( ( bExp == 0xFF ) && bSig ) ) {
12361da177e4SLinus Torvalds return propagateFloat32NaN( a, b );
12371da177e4SLinus Torvalds }
12381da177e4SLinus Torvalds if ( ( bExp | bSig ) == 0 ) {
1239f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
12401da177e4SLinus Torvalds return float32_default_nan;
12411da177e4SLinus Torvalds }
12421da177e4SLinus Torvalds return packFloat32( zSign, 0xFF, 0 );
12431da177e4SLinus Torvalds }
12441da177e4SLinus Torvalds if ( bExp == 0xFF ) {
12451da177e4SLinus Torvalds if ( bSig ) return propagateFloat32NaN( a, b );
12461da177e4SLinus Torvalds if ( ( aExp | aSig ) == 0 ) {
1247f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
12481da177e4SLinus Torvalds return float32_default_nan;
12491da177e4SLinus Torvalds }
12501da177e4SLinus Torvalds return packFloat32( zSign, 0xFF, 0 );
12511da177e4SLinus Torvalds }
12521da177e4SLinus Torvalds if ( aExp == 0 ) {
12531da177e4SLinus Torvalds if ( aSig == 0 ) return packFloat32( zSign, 0, 0 );
12541da177e4SLinus Torvalds normalizeFloat32Subnormal( aSig, &aExp, &aSig );
12551da177e4SLinus Torvalds }
12561da177e4SLinus Torvalds if ( bExp == 0 ) {
12571da177e4SLinus Torvalds if ( bSig == 0 ) return packFloat32( zSign, 0, 0 );
12581da177e4SLinus Torvalds normalizeFloat32Subnormal( bSig, &bExp, &bSig );
12591da177e4SLinus Torvalds }
12601da177e4SLinus Torvalds zExp = aExp + bExp - 0x7F;
12611da177e4SLinus Torvalds aSig = ( aSig | 0x00800000 )<<7;
12621da177e4SLinus Torvalds bSig = ( bSig | 0x00800000 )<<8;
12631da177e4SLinus Torvalds shift64RightJamming( ( (bits64) aSig ) * bSig, 32, &zSig64 );
12641da177e4SLinus Torvalds zSig = zSig64;
12651da177e4SLinus Torvalds if ( 0 <= (sbits32) ( zSig<<1 ) ) {
12661da177e4SLinus Torvalds zSig <<= 1;
12671da177e4SLinus Torvalds --zExp;
12681da177e4SLinus Torvalds }
1269f148af25SRichard Purdie return roundAndPackFloat32( roundData, zSign, zExp, zSig );
12701da177e4SLinus Torvalds
12711da177e4SLinus Torvalds }
12721da177e4SLinus Torvalds
12731da177e4SLinus Torvalds /*
12741da177e4SLinus Torvalds -------------------------------------------------------------------------------
12751da177e4SLinus Torvalds Returns the result of dividing the single-precision floating-point value `a'
12761da177e4SLinus Torvalds by the corresponding value `b'. The operation is performed according to the
12771da177e4SLinus Torvalds IEC/IEEE Standard for Binary Floating-point Arithmetic.
12781da177e4SLinus Torvalds -------------------------------------------------------------------------------
12791da177e4SLinus Torvalds */
float32_div(struct roundingData * roundData,float32 a,float32 b)1280f148af25SRichard Purdie float32 float32_div( struct roundingData *roundData, float32 a, float32 b )
12811da177e4SLinus Torvalds {
12821da177e4SLinus Torvalds flag aSign, bSign, zSign;
12831da177e4SLinus Torvalds int16 aExp, bExp, zExp;
12841da177e4SLinus Torvalds bits32 aSig, bSig, zSig;
12851da177e4SLinus Torvalds
12861da177e4SLinus Torvalds aSig = extractFloat32Frac( a );
12871da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
12881da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
12891da177e4SLinus Torvalds bSig = extractFloat32Frac( b );
12901da177e4SLinus Torvalds bExp = extractFloat32Exp( b );
12911da177e4SLinus Torvalds bSign = extractFloat32Sign( b );
12921da177e4SLinus Torvalds zSign = aSign ^ bSign;
12931da177e4SLinus Torvalds if ( aExp == 0xFF ) {
12941da177e4SLinus Torvalds if ( aSig ) return propagateFloat32NaN( a, b );
12951da177e4SLinus Torvalds if ( bExp == 0xFF ) {
12961da177e4SLinus Torvalds if ( bSig ) return propagateFloat32NaN( a, b );
1297f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
12981da177e4SLinus Torvalds return float32_default_nan;
12991da177e4SLinus Torvalds }
13001da177e4SLinus Torvalds return packFloat32( zSign, 0xFF, 0 );
13011da177e4SLinus Torvalds }
13021da177e4SLinus Torvalds if ( bExp == 0xFF ) {
13031da177e4SLinus Torvalds if ( bSig ) return propagateFloat32NaN( a, b );
13041da177e4SLinus Torvalds return packFloat32( zSign, 0, 0 );
13051da177e4SLinus Torvalds }
13061da177e4SLinus Torvalds if ( bExp == 0 ) {
13071da177e4SLinus Torvalds if ( bSig == 0 ) {
13081da177e4SLinus Torvalds if ( ( aExp | aSig ) == 0 ) {
1309f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
13101da177e4SLinus Torvalds return float32_default_nan;
13111da177e4SLinus Torvalds }
1312f148af25SRichard Purdie roundData->exception |= float_flag_divbyzero;
13131da177e4SLinus Torvalds return packFloat32( zSign, 0xFF, 0 );
13141da177e4SLinus Torvalds }
13151da177e4SLinus Torvalds normalizeFloat32Subnormal( bSig, &bExp, &bSig );
13161da177e4SLinus Torvalds }
13171da177e4SLinus Torvalds if ( aExp == 0 ) {
13181da177e4SLinus Torvalds if ( aSig == 0 ) return packFloat32( zSign, 0, 0 );
13191da177e4SLinus Torvalds normalizeFloat32Subnormal( aSig, &aExp, &aSig );
13201da177e4SLinus Torvalds }
13211da177e4SLinus Torvalds zExp = aExp - bExp + 0x7D;
13221da177e4SLinus Torvalds aSig = ( aSig | 0x00800000 )<<7;
13231da177e4SLinus Torvalds bSig = ( bSig | 0x00800000 )<<8;
13241da177e4SLinus Torvalds if ( bSig <= ( aSig + aSig ) ) {
13251da177e4SLinus Torvalds aSig >>= 1;
13261da177e4SLinus Torvalds ++zExp;
13271da177e4SLinus Torvalds }
1328c1241c4cSNicolas Pitre {
1329c1241c4cSNicolas Pitre bits64 tmp = ( (bits64) aSig )<<32;
1330c1241c4cSNicolas Pitre do_div( tmp, bSig );
1331c1241c4cSNicolas Pitre zSig = tmp;
1332c1241c4cSNicolas Pitre }
13331da177e4SLinus Torvalds if ( ( zSig & 0x3F ) == 0 ) {
13341da177e4SLinus Torvalds zSig |= ( ( (bits64) bSig ) * zSig != ( (bits64) aSig )<<32 );
13351da177e4SLinus Torvalds }
1336f148af25SRichard Purdie return roundAndPackFloat32( roundData, zSign, zExp, zSig );
13371da177e4SLinus Torvalds
13381da177e4SLinus Torvalds }
13391da177e4SLinus Torvalds
13401da177e4SLinus Torvalds /*
13411da177e4SLinus Torvalds -------------------------------------------------------------------------------
13421da177e4SLinus Torvalds Returns the remainder of the single-precision floating-point value `a'
13431da177e4SLinus Torvalds with respect to the corresponding value `b'. The operation is performed
13441da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
13451da177e4SLinus Torvalds -------------------------------------------------------------------------------
13461da177e4SLinus Torvalds */
float32_rem(struct roundingData * roundData,float32 a,float32 b)1347f148af25SRichard Purdie float32 float32_rem( struct roundingData *roundData, float32 a, float32 b )
13481da177e4SLinus Torvalds {
13491da177e4SLinus Torvalds flag aSign, bSign, zSign;
13501da177e4SLinus Torvalds int16 aExp, bExp, expDiff;
13511da177e4SLinus Torvalds bits32 aSig, bSig;
13521da177e4SLinus Torvalds bits32 q;
13531da177e4SLinus Torvalds bits64 aSig64, bSig64, q64;
13541da177e4SLinus Torvalds bits32 alternateASig;
13551da177e4SLinus Torvalds sbits32 sigMean;
13561da177e4SLinus Torvalds
13571da177e4SLinus Torvalds aSig = extractFloat32Frac( a );
13581da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
13591da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
13601da177e4SLinus Torvalds bSig = extractFloat32Frac( b );
13611da177e4SLinus Torvalds bExp = extractFloat32Exp( b );
13621da177e4SLinus Torvalds bSign = extractFloat32Sign( b );
13631da177e4SLinus Torvalds if ( aExp == 0xFF ) {
13641da177e4SLinus Torvalds if ( aSig || ( ( bExp == 0xFF ) && bSig ) ) {
13651da177e4SLinus Torvalds return propagateFloat32NaN( a, b );
13661da177e4SLinus Torvalds }
1367f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
13681da177e4SLinus Torvalds return float32_default_nan;
13691da177e4SLinus Torvalds }
13701da177e4SLinus Torvalds if ( bExp == 0xFF ) {
13711da177e4SLinus Torvalds if ( bSig ) return propagateFloat32NaN( a, b );
13721da177e4SLinus Torvalds return a;
13731da177e4SLinus Torvalds }
13741da177e4SLinus Torvalds if ( bExp == 0 ) {
13751da177e4SLinus Torvalds if ( bSig == 0 ) {
1376f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
13771da177e4SLinus Torvalds return float32_default_nan;
13781da177e4SLinus Torvalds }
13791da177e4SLinus Torvalds normalizeFloat32Subnormal( bSig, &bExp, &bSig );
13801da177e4SLinus Torvalds }
13811da177e4SLinus Torvalds if ( aExp == 0 ) {
13821da177e4SLinus Torvalds if ( aSig == 0 ) return a;
13831da177e4SLinus Torvalds normalizeFloat32Subnormal( aSig, &aExp, &aSig );
13841da177e4SLinus Torvalds }
13851da177e4SLinus Torvalds expDiff = aExp - bExp;
13861da177e4SLinus Torvalds aSig |= 0x00800000;
13871da177e4SLinus Torvalds bSig |= 0x00800000;
13881da177e4SLinus Torvalds if ( expDiff < 32 ) {
13891da177e4SLinus Torvalds aSig <<= 8;
13901da177e4SLinus Torvalds bSig <<= 8;
13911da177e4SLinus Torvalds if ( expDiff < 0 ) {
13921da177e4SLinus Torvalds if ( expDiff < -1 ) return a;
13931da177e4SLinus Torvalds aSig >>= 1;
13941da177e4SLinus Torvalds }
13951da177e4SLinus Torvalds q = ( bSig <= aSig );
13961da177e4SLinus Torvalds if ( q ) aSig -= bSig;
13971da177e4SLinus Torvalds if ( 0 < expDiff ) {
1398c1241c4cSNicolas Pitre bits64 tmp = ( (bits64) aSig )<<32;
1399c1241c4cSNicolas Pitre do_div( tmp, bSig );
1400c1241c4cSNicolas Pitre q = tmp;
14011da177e4SLinus Torvalds q >>= 32 - expDiff;
14021da177e4SLinus Torvalds bSig >>= 2;
14031da177e4SLinus Torvalds aSig = ( ( aSig>>1 )<<( expDiff - 1 ) ) - bSig * q;
14041da177e4SLinus Torvalds }
14051da177e4SLinus Torvalds else {
14061da177e4SLinus Torvalds aSig >>= 2;
14071da177e4SLinus Torvalds bSig >>= 2;
14081da177e4SLinus Torvalds }
14091da177e4SLinus Torvalds }
14101da177e4SLinus Torvalds else {
14111da177e4SLinus Torvalds if ( bSig <= aSig ) aSig -= bSig;
14121da177e4SLinus Torvalds aSig64 = ( (bits64) aSig )<<40;
14131da177e4SLinus Torvalds bSig64 = ( (bits64) bSig )<<40;
14141da177e4SLinus Torvalds expDiff -= 64;
14151da177e4SLinus Torvalds while ( 0 < expDiff ) {
14161da177e4SLinus Torvalds q64 = estimateDiv128To64( aSig64, 0, bSig64 );
14171da177e4SLinus Torvalds q64 = ( 2 < q64 ) ? q64 - 2 : 0;
14181da177e4SLinus Torvalds aSig64 = - ( ( bSig * q64 )<<38 );
14191da177e4SLinus Torvalds expDiff -= 62;
14201da177e4SLinus Torvalds }
14211da177e4SLinus Torvalds expDiff += 64;
14221da177e4SLinus Torvalds q64 = estimateDiv128To64( aSig64, 0, bSig64 );
14231da177e4SLinus Torvalds q64 = ( 2 < q64 ) ? q64 - 2 : 0;
14241da177e4SLinus Torvalds q = q64>>( 64 - expDiff );
14251da177e4SLinus Torvalds bSig <<= 6;
14261da177e4SLinus Torvalds aSig = ( ( aSig64>>33 )<<( expDiff - 1 ) ) - bSig * q;
14271da177e4SLinus Torvalds }
14281da177e4SLinus Torvalds do {
14291da177e4SLinus Torvalds alternateASig = aSig;
14301da177e4SLinus Torvalds ++q;
14311da177e4SLinus Torvalds aSig -= bSig;
14321da177e4SLinus Torvalds } while ( 0 <= (sbits32) aSig );
14331da177e4SLinus Torvalds sigMean = aSig + alternateASig;
14341da177e4SLinus Torvalds if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) {
14351da177e4SLinus Torvalds aSig = alternateASig;
14361da177e4SLinus Torvalds }
14371da177e4SLinus Torvalds zSign = ( (sbits32) aSig < 0 );
14381da177e4SLinus Torvalds if ( zSign ) aSig = - aSig;
1439f148af25SRichard Purdie return normalizeRoundAndPackFloat32( roundData, aSign ^ zSign, bExp, aSig );
14401da177e4SLinus Torvalds
14411da177e4SLinus Torvalds }
14421da177e4SLinus Torvalds
14431da177e4SLinus Torvalds /*
14441da177e4SLinus Torvalds -------------------------------------------------------------------------------
14451da177e4SLinus Torvalds Returns the square root of the single-precision floating-point value `a'.
14461da177e4SLinus Torvalds The operation is performed according to the IEC/IEEE Standard for Binary
14471da177e4SLinus Torvalds Floating-point Arithmetic.
14481da177e4SLinus Torvalds -------------------------------------------------------------------------------
14491da177e4SLinus Torvalds */
float32_sqrt(struct roundingData * roundData,float32 a)1450f148af25SRichard Purdie float32 float32_sqrt( struct roundingData *roundData, float32 a )
14511da177e4SLinus Torvalds {
14521da177e4SLinus Torvalds flag aSign;
14531da177e4SLinus Torvalds int16 aExp, zExp;
14541da177e4SLinus Torvalds bits32 aSig, zSig;
14551da177e4SLinus Torvalds bits64 rem, term;
14561da177e4SLinus Torvalds
14571da177e4SLinus Torvalds aSig = extractFloat32Frac( a );
14581da177e4SLinus Torvalds aExp = extractFloat32Exp( a );
14591da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
14601da177e4SLinus Torvalds if ( aExp == 0xFF ) {
14611da177e4SLinus Torvalds if ( aSig ) return propagateFloat32NaN( a, 0 );
14621da177e4SLinus Torvalds if ( ! aSign ) return a;
1463f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
14641da177e4SLinus Torvalds return float32_default_nan;
14651da177e4SLinus Torvalds }
14661da177e4SLinus Torvalds if ( aSign ) {
14671da177e4SLinus Torvalds if ( ( aExp | aSig ) == 0 ) return a;
1468f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
14691da177e4SLinus Torvalds return float32_default_nan;
14701da177e4SLinus Torvalds }
14711da177e4SLinus Torvalds if ( aExp == 0 ) {
14721da177e4SLinus Torvalds if ( aSig == 0 ) return 0;
14731da177e4SLinus Torvalds normalizeFloat32Subnormal( aSig, &aExp, &aSig );
14741da177e4SLinus Torvalds }
14751da177e4SLinus Torvalds zExp = ( ( aExp - 0x7F )>>1 ) + 0x7E;
14761da177e4SLinus Torvalds aSig = ( aSig | 0x00800000 )<<8;
14771da177e4SLinus Torvalds zSig = estimateSqrt32( aExp, aSig ) + 2;
14781da177e4SLinus Torvalds if ( ( zSig & 0x7F ) <= 5 ) {
14791da177e4SLinus Torvalds if ( zSig < 2 ) {
14801da177e4SLinus Torvalds zSig = 0xFFFFFFFF;
14811da177e4SLinus Torvalds }
14821da177e4SLinus Torvalds else {
14831da177e4SLinus Torvalds aSig >>= aExp & 1;
14841da177e4SLinus Torvalds term = ( (bits64) zSig ) * zSig;
14851da177e4SLinus Torvalds rem = ( ( (bits64) aSig )<<32 ) - term;
14861da177e4SLinus Torvalds while ( (sbits64) rem < 0 ) {
14871da177e4SLinus Torvalds --zSig;
14881da177e4SLinus Torvalds rem += ( ( (bits64) zSig )<<1 ) | 1;
14891da177e4SLinus Torvalds }
14901da177e4SLinus Torvalds zSig |= ( rem != 0 );
14911da177e4SLinus Torvalds }
14921da177e4SLinus Torvalds }
14931da177e4SLinus Torvalds shift32RightJamming( zSig, 1, &zSig );
1494f148af25SRichard Purdie return roundAndPackFloat32( roundData, 0, zExp, zSig );
14951da177e4SLinus Torvalds
14961da177e4SLinus Torvalds }
14971da177e4SLinus Torvalds
14981da177e4SLinus Torvalds /*
14991da177e4SLinus Torvalds -------------------------------------------------------------------------------
15001da177e4SLinus Torvalds Returns 1 if the single-precision floating-point value `a' is equal to the
15011da177e4SLinus Torvalds corresponding value `b', and 0 otherwise. The comparison is performed
15021da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
15031da177e4SLinus Torvalds -------------------------------------------------------------------------------
15041da177e4SLinus Torvalds */
float32_eq(float32 a,float32 b)15051da177e4SLinus Torvalds flag float32_eq( float32 a, float32 b )
15061da177e4SLinus Torvalds {
15071da177e4SLinus Torvalds
15081da177e4SLinus Torvalds if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
15091da177e4SLinus Torvalds || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
15101da177e4SLinus Torvalds ) {
15111da177e4SLinus Torvalds if ( float32_is_signaling_nan( a ) || float32_is_signaling_nan( b ) ) {
15121da177e4SLinus Torvalds float_raise( float_flag_invalid );
15131da177e4SLinus Torvalds }
15141da177e4SLinus Torvalds return 0;
15151da177e4SLinus Torvalds }
15161da177e4SLinus Torvalds return ( a == b ) || ( (bits32) ( ( a | b )<<1 ) == 0 );
15171da177e4SLinus Torvalds
15181da177e4SLinus Torvalds }
15191da177e4SLinus Torvalds
15201da177e4SLinus Torvalds /*
15211da177e4SLinus Torvalds -------------------------------------------------------------------------------
15221da177e4SLinus Torvalds Returns 1 if the single-precision floating-point value `a' is less than or
15231da177e4SLinus Torvalds equal to the corresponding value `b', and 0 otherwise. The comparison is
15241da177e4SLinus Torvalds performed according to the IEC/IEEE Standard for Binary Floating-point
15251da177e4SLinus Torvalds Arithmetic.
15261da177e4SLinus Torvalds -------------------------------------------------------------------------------
15271da177e4SLinus Torvalds */
float32_le(float32 a,float32 b)15281da177e4SLinus Torvalds flag float32_le( float32 a, float32 b )
15291da177e4SLinus Torvalds {
15301da177e4SLinus Torvalds flag aSign, bSign;
15311da177e4SLinus Torvalds
15321da177e4SLinus Torvalds if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
15331da177e4SLinus Torvalds || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
15341da177e4SLinus Torvalds ) {
15351da177e4SLinus Torvalds float_raise( float_flag_invalid );
15361da177e4SLinus Torvalds return 0;
15371da177e4SLinus Torvalds }
15381da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
15391da177e4SLinus Torvalds bSign = extractFloat32Sign( b );
15401da177e4SLinus Torvalds if ( aSign != bSign ) return aSign || ( (bits32) ( ( a | b )<<1 ) == 0 );
15411da177e4SLinus Torvalds return ( a == b ) || ( aSign ^ ( a < b ) );
15421da177e4SLinus Torvalds
15431da177e4SLinus Torvalds }
15441da177e4SLinus Torvalds
15451da177e4SLinus Torvalds /*
15461da177e4SLinus Torvalds -------------------------------------------------------------------------------
15471da177e4SLinus Torvalds Returns 1 if the single-precision floating-point value `a' is less than
15481da177e4SLinus Torvalds the corresponding value `b', and 0 otherwise. The comparison is performed
15491da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
15501da177e4SLinus Torvalds -------------------------------------------------------------------------------
15511da177e4SLinus Torvalds */
float32_lt(float32 a,float32 b)15521da177e4SLinus Torvalds flag float32_lt( float32 a, float32 b )
15531da177e4SLinus Torvalds {
15541da177e4SLinus Torvalds flag aSign, bSign;
15551da177e4SLinus Torvalds
15561da177e4SLinus Torvalds if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
15571da177e4SLinus Torvalds || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
15581da177e4SLinus Torvalds ) {
15591da177e4SLinus Torvalds float_raise( float_flag_invalid );
15601da177e4SLinus Torvalds return 0;
15611da177e4SLinus Torvalds }
15621da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
15631da177e4SLinus Torvalds bSign = extractFloat32Sign( b );
15641da177e4SLinus Torvalds if ( aSign != bSign ) return aSign && ( (bits32) ( ( a | b )<<1 ) != 0 );
15651da177e4SLinus Torvalds return ( a != b ) && ( aSign ^ ( a < b ) );
15661da177e4SLinus Torvalds
15671da177e4SLinus Torvalds }
15681da177e4SLinus Torvalds
15691da177e4SLinus Torvalds /*
15701da177e4SLinus Torvalds -------------------------------------------------------------------------------
15711da177e4SLinus Torvalds Returns 1 if the single-precision floating-point value `a' is equal to the
15721da177e4SLinus Torvalds corresponding value `b', and 0 otherwise. The invalid exception is raised
15731da177e4SLinus Torvalds if either operand is a NaN. Otherwise, the comparison is performed
15741da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
15751da177e4SLinus Torvalds -------------------------------------------------------------------------------
15761da177e4SLinus Torvalds */
float32_eq_signaling(float32 a,float32 b)15771da177e4SLinus Torvalds flag float32_eq_signaling( float32 a, float32 b )
15781da177e4SLinus Torvalds {
15791da177e4SLinus Torvalds
15801da177e4SLinus Torvalds if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
15811da177e4SLinus Torvalds || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
15821da177e4SLinus Torvalds ) {
15831da177e4SLinus Torvalds float_raise( float_flag_invalid );
15841da177e4SLinus Torvalds return 0;
15851da177e4SLinus Torvalds }
15861da177e4SLinus Torvalds return ( a == b ) || ( (bits32) ( ( a | b )<<1 ) == 0 );
15871da177e4SLinus Torvalds
15881da177e4SLinus Torvalds }
15891da177e4SLinus Torvalds
15901da177e4SLinus Torvalds /*
15911da177e4SLinus Torvalds -------------------------------------------------------------------------------
15921da177e4SLinus Torvalds Returns 1 if the single-precision floating-point value `a' is less than or
15931da177e4SLinus Torvalds equal to the corresponding value `b', and 0 otherwise. Quiet NaNs do not
15941da177e4SLinus Torvalds cause an exception. Otherwise, the comparison is performed according to the
15951da177e4SLinus Torvalds IEC/IEEE Standard for Binary Floating-point Arithmetic.
15961da177e4SLinus Torvalds -------------------------------------------------------------------------------
15971da177e4SLinus Torvalds */
float32_le_quiet(float32 a,float32 b)15981da177e4SLinus Torvalds flag float32_le_quiet( float32 a, float32 b )
15991da177e4SLinus Torvalds {
16001da177e4SLinus Torvalds flag aSign, bSign;
16011da177e4SLinus Torvalds //int16 aExp, bExp;
16021da177e4SLinus Torvalds
16031da177e4SLinus Torvalds if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
16041da177e4SLinus Torvalds || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
16051da177e4SLinus Torvalds ) {
160654738e82SRichard Purdie /* Do nothing, even if NaN as we're quiet */
16071da177e4SLinus Torvalds return 0;
16081da177e4SLinus Torvalds }
16091da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
16101da177e4SLinus Torvalds bSign = extractFloat32Sign( b );
16111da177e4SLinus Torvalds if ( aSign != bSign ) return aSign || ( (bits32) ( ( a | b )<<1 ) == 0 );
16121da177e4SLinus Torvalds return ( a == b ) || ( aSign ^ ( a < b ) );
16131da177e4SLinus Torvalds
16141da177e4SLinus Torvalds }
16151da177e4SLinus Torvalds
16161da177e4SLinus Torvalds /*
16171da177e4SLinus Torvalds -------------------------------------------------------------------------------
16181da177e4SLinus Torvalds Returns 1 if the single-precision floating-point value `a' is less than
16191da177e4SLinus Torvalds the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an
16201da177e4SLinus Torvalds exception. Otherwise, the comparison is performed according to the IEC/IEEE
16211da177e4SLinus Torvalds Standard for Binary Floating-point Arithmetic.
16221da177e4SLinus Torvalds -------------------------------------------------------------------------------
16231da177e4SLinus Torvalds */
float32_lt_quiet(float32 a,float32 b)16241da177e4SLinus Torvalds flag float32_lt_quiet( float32 a, float32 b )
16251da177e4SLinus Torvalds {
16261da177e4SLinus Torvalds flag aSign, bSign;
16271da177e4SLinus Torvalds
16281da177e4SLinus Torvalds if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) )
16291da177e4SLinus Torvalds || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) )
16301da177e4SLinus Torvalds ) {
163154738e82SRichard Purdie /* Do nothing, even if NaN as we're quiet */
16321da177e4SLinus Torvalds return 0;
16331da177e4SLinus Torvalds }
16341da177e4SLinus Torvalds aSign = extractFloat32Sign( a );
16351da177e4SLinus Torvalds bSign = extractFloat32Sign( b );
16361da177e4SLinus Torvalds if ( aSign != bSign ) return aSign && ( (bits32) ( ( a | b )<<1 ) != 0 );
16371da177e4SLinus Torvalds return ( a != b ) && ( aSign ^ ( a < b ) );
16381da177e4SLinus Torvalds
16391da177e4SLinus Torvalds }
16401da177e4SLinus Torvalds
16411da177e4SLinus Torvalds /*
16421da177e4SLinus Torvalds -------------------------------------------------------------------------------
16431da177e4SLinus Torvalds Returns the result of converting the double-precision floating-point value
16441da177e4SLinus Torvalds `a' to the 32-bit two's complement integer format. The conversion is
16451da177e4SLinus Torvalds performed according to the IEC/IEEE Standard for Binary Floating-point
16461da177e4SLinus Torvalds Arithmetic---which means in particular that the conversion is rounded
16471da177e4SLinus Torvalds according to the current rounding mode. If `a' is a NaN, the largest
16481da177e4SLinus Torvalds positive integer is returned. Otherwise, if the conversion overflows, the
16491da177e4SLinus Torvalds largest integer with the same sign as `a' is returned.
16501da177e4SLinus Torvalds -------------------------------------------------------------------------------
16511da177e4SLinus Torvalds */
float64_to_int32(struct roundingData * roundData,float64 a)1652f148af25SRichard Purdie int32 float64_to_int32( struct roundingData *roundData, float64 a )
16531da177e4SLinus Torvalds {
16541da177e4SLinus Torvalds flag aSign;
16551da177e4SLinus Torvalds int16 aExp, shiftCount;
16561da177e4SLinus Torvalds bits64 aSig;
16571da177e4SLinus Torvalds
16581da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
16591da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
16601da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
16611da177e4SLinus Torvalds if ( ( aExp == 0x7FF ) && aSig ) aSign = 0;
16621da177e4SLinus Torvalds if ( aExp ) aSig |= LIT64( 0x0010000000000000 );
16631da177e4SLinus Torvalds shiftCount = 0x42C - aExp;
16641da177e4SLinus Torvalds if ( 0 < shiftCount ) shift64RightJamming( aSig, shiftCount, &aSig );
1665f148af25SRichard Purdie return roundAndPackInt32( roundData, aSign, aSig );
16661da177e4SLinus Torvalds
16671da177e4SLinus Torvalds }
16681da177e4SLinus Torvalds
16691da177e4SLinus Torvalds /*
16701da177e4SLinus Torvalds -------------------------------------------------------------------------------
16711da177e4SLinus Torvalds Returns the result of converting the double-precision floating-point value
16721da177e4SLinus Torvalds `a' to the 32-bit two's complement integer format. The conversion is
16731da177e4SLinus Torvalds performed according to the IEC/IEEE Standard for Binary Floating-point
16741da177e4SLinus Torvalds Arithmetic, except that the conversion is always rounded toward zero. If
16751da177e4SLinus Torvalds `a' is a NaN, the largest positive integer is returned. Otherwise, if the
16761da177e4SLinus Torvalds conversion overflows, the largest integer with the same sign as `a' is
16771da177e4SLinus Torvalds returned.
16781da177e4SLinus Torvalds -------------------------------------------------------------------------------
16791da177e4SLinus Torvalds */
float64_to_int32_round_to_zero(float64 a)16801da177e4SLinus Torvalds int32 float64_to_int32_round_to_zero( float64 a )
16811da177e4SLinus Torvalds {
16821da177e4SLinus Torvalds flag aSign;
16831da177e4SLinus Torvalds int16 aExp, shiftCount;
16841da177e4SLinus Torvalds bits64 aSig, savedASig;
16851da177e4SLinus Torvalds int32 z;
16861da177e4SLinus Torvalds
16871da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
16881da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
16891da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
16901da177e4SLinus Torvalds shiftCount = 0x433 - aExp;
16911da177e4SLinus Torvalds if ( shiftCount < 21 ) {
16921da177e4SLinus Torvalds if ( ( aExp == 0x7FF ) && aSig ) aSign = 0;
16931da177e4SLinus Torvalds goto invalid;
16941da177e4SLinus Torvalds }
16951da177e4SLinus Torvalds else if ( 52 < shiftCount ) {
1696f148af25SRichard Purdie if ( aExp || aSig ) float_raise( float_flag_inexact );
16971da177e4SLinus Torvalds return 0;
16981da177e4SLinus Torvalds }
16991da177e4SLinus Torvalds aSig |= LIT64( 0x0010000000000000 );
17001da177e4SLinus Torvalds savedASig = aSig;
17011da177e4SLinus Torvalds aSig >>= shiftCount;
17021da177e4SLinus Torvalds z = aSig;
17031da177e4SLinus Torvalds if ( aSign ) z = - z;
17041da177e4SLinus Torvalds if ( ( z < 0 ) ^ aSign ) {
17051da177e4SLinus Torvalds invalid:
1706f148af25SRichard Purdie float_raise( float_flag_invalid );
17071da177e4SLinus Torvalds return aSign ? 0x80000000 : 0x7FFFFFFF;
17081da177e4SLinus Torvalds }
17091da177e4SLinus Torvalds if ( ( aSig<<shiftCount ) != savedASig ) {
1710f148af25SRichard Purdie float_raise( float_flag_inexact );
17111da177e4SLinus Torvalds }
17121da177e4SLinus Torvalds return z;
17131da177e4SLinus Torvalds
17141da177e4SLinus Torvalds }
17151da177e4SLinus Torvalds
17161da177e4SLinus Torvalds /*
17171da177e4SLinus Torvalds -------------------------------------------------------------------------------
17181da177e4SLinus Torvalds Returns the result of converting the double-precision floating-point value
17191da177e4SLinus Torvalds `a' to the 32-bit two's complement unsigned integer format. The conversion
17201da177e4SLinus Torvalds is performed according to the IEC/IEEE Standard for Binary Floating-point
17211da177e4SLinus Torvalds Arithmetic---which means in particular that the conversion is rounded
17221da177e4SLinus Torvalds according to the current rounding mode. If `a' is a NaN, the largest
17231da177e4SLinus Torvalds positive integer is returned. Otherwise, if the conversion overflows, the
17241da177e4SLinus Torvalds largest positive integer is returned.
17251da177e4SLinus Torvalds -------------------------------------------------------------------------------
17261da177e4SLinus Torvalds */
float64_to_uint32(struct roundingData * roundData,float64 a)1727f148af25SRichard Purdie int32 float64_to_uint32( struct roundingData *roundData, float64 a )
17281da177e4SLinus Torvalds {
17291da177e4SLinus Torvalds flag aSign;
17301da177e4SLinus Torvalds int16 aExp, shiftCount;
17311da177e4SLinus Torvalds bits64 aSig;
17321da177e4SLinus Torvalds
17331da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
17341da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
17351da177e4SLinus Torvalds aSign = 0; //extractFloat64Sign( a );
17361da177e4SLinus Torvalds //if ( ( aExp == 0x7FF ) && aSig ) aSign = 0;
17371da177e4SLinus Torvalds if ( aExp ) aSig |= LIT64( 0x0010000000000000 );
17381da177e4SLinus Torvalds shiftCount = 0x42C - aExp;
17391da177e4SLinus Torvalds if ( 0 < shiftCount ) shift64RightJamming( aSig, shiftCount, &aSig );
1740f148af25SRichard Purdie return roundAndPackInt32( roundData, aSign, aSig );
17411da177e4SLinus Torvalds }
17421da177e4SLinus Torvalds
17431da177e4SLinus Torvalds /*
17441da177e4SLinus Torvalds -------------------------------------------------------------------------------
17451da177e4SLinus Torvalds Returns the result of converting the double-precision floating-point value
17461da177e4SLinus Torvalds `a' to the 32-bit two's complement integer format. The conversion is
17471da177e4SLinus Torvalds performed according to the IEC/IEEE Standard for Binary Floating-point
17481da177e4SLinus Torvalds Arithmetic, except that the conversion is always rounded toward zero. If
17491da177e4SLinus Torvalds `a' is a NaN, the largest positive integer is returned. Otherwise, if the
17501da177e4SLinus Torvalds conversion overflows, the largest positive integer is returned.
17511da177e4SLinus Torvalds -------------------------------------------------------------------------------
17521da177e4SLinus Torvalds */
float64_to_uint32_round_to_zero(float64 a)17531da177e4SLinus Torvalds int32 float64_to_uint32_round_to_zero( float64 a )
17541da177e4SLinus Torvalds {
17551da177e4SLinus Torvalds flag aSign;
17561da177e4SLinus Torvalds int16 aExp, shiftCount;
17571da177e4SLinus Torvalds bits64 aSig, savedASig;
17581da177e4SLinus Torvalds int32 z;
17591da177e4SLinus Torvalds
17601da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
17611da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
17621da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
17631da177e4SLinus Torvalds shiftCount = 0x433 - aExp;
17641da177e4SLinus Torvalds if ( shiftCount < 21 ) {
17651da177e4SLinus Torvalds if ( ( aExp == 0x7FF ) && aSig ) aSign = 0;
17661da177e4SLinus Torvalds goto invalid;
17671da177e4SLinus Torvalds }
17681da177e4SLinus Torvalds else if ( 52 < shiftCount ) {
1769f148af25SRichard Purdie if ( aExp || aSig ) float_raise( float_flag_inexact );
17701da177e4SLinus Torvalds return 0;
17711da177e4SLinus Torvalds }
17721da177e4SLinus Torvalds aSig |= LIT64( 0x0010000000000000 );
17731da177e4SLinus Torvalds savedASig = aSig;
17741da177e4SLinus Torvalds aSig >>= shiftCount;
17751da177e4SLinus Torvalds z = aSig;
17761da177e4SLinus Torvalds if ( aSign ) z = - z;
17771da177e4SLinus Torvalds if ( ( z < 0 ) ^ aSign ) {
17781da177e4SLinus Torvalds invalid:
1779f148af25SRichard Purdie float_raise( float_flag_invalid );
17801da177e4SLinus Torvalds return aSign ? 0x80000000 : 0x7FFFFFFF;
17811da177e4SLinus Torvalds }
17821da177e4SLinus Torvalds if ( ( aSig<<shiftCount ) != savedASig ) {
1783f148af25SRichard Purdie float_raise( float_flag_inexact );
17841da177e4SLinus Torvalds }
17851da177e4SLinus Torvalds return z;
17861da177e4SLinus Torvalds }
17871da177e4SLinus Torvalds
17881da177e4SLinus Torvalds /*
17891da177e4SLinus Torvalds -------------------------------------------------------------------------------
17901da177e4SLinus Torvalds Returns the result of converting the double-precision floating-point value
17911da177e4SLinus Torvalds `a' to the single-precision floating-point format. The conversion is
17921da177e4SLinus Torvalds performed according to the IEC/IEEE Standard for Binary Floating-point
17931da177e4SLinus Torvalds Arithmetic.
17941da177e4SLinus Torvalds -------------------------------------------------------------------------------
17951da177e4SLinus Torvalds */
float64_to_float32(struct roundingData * roundData,float64 a)1796f148af25SRichard Purdie float32 float64_to_float32( struct roundingData *roundData, float64 a )
17971da177e4SLinus Torvalds {
17981da177e4SLinus Torvalds flag aSign;
17991da177e4SLinus Torvalds int16 aExp;
18001da177e4SLinus Torvalds bits64 aSig;
18011da177e4SLinus Torvalds bits32 zSig;
18021da177e4SLinus Torvalds
18031da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
18041da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
18051da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
18061da177e4SLinus Torvalds if ( aExp == 0x7FF ) {
18071da177e4SLinus Torvalds if ( aSig ) return commonNaNToFloat32( float64ToCommonNaN( a ) );
18081da177e4SLinus Torvalds return packFloat32( aSign, 0xFF, 0 );
18091da177e4SLinus Torvalds }
18101da177e4SLinus Torvalds shift64RightJamming( aSig, 22, &aSig );
18111da177e4SLinus Torvalds zSig = aSig;
18121da177e4SLinus Torvalds if ( aExp || zSig ) {
18131da177e4SLinus Torvalds zSig |= 0x40000000;
18141da177e4SLinus Torvalds aExp -= 0x381;
18151da177e4SLinus Torvalds }
1816f148af25SRichard Purdie return roundAndPackFloat32( roundData, aSign, aExp, zSig );
18171da177e4SLinus Torvalds
18181da177e4SLinus Torvalds }
18191da177e4SLinus Torvalds
18201da177e4SLinus Torvalds #ifdef FLOATX80
18211da177e4SLinus Torvalds
18221da177e4SLinus Torvalds /*
18231da177e4SLinus Torvalds -------------------------------------------------------------------------------
18241da177e4SLinus Torvalds Returns the result of converting the double-precision floating-point value
18251da177e4SLinus Torvalds `a' to the extended double-precision floating-point format. The conversion
18261da177e4SLinus Torvalds is performed according to the IEC/IEEE Standard for Binary Floating-point
18271da177e4SLinus Torvalds Arithmetic.
18281da177e4SLinus Torvalds -------------------------------------------------------------------------------
18291da177e4SLinus Torvalds */
float64_to_floatx80(float64 a)18301da177e4SLinus Torvalds floatx80 float64_to_floatx80( float64 a )
18311da177e4SLinus Torvalds {
18321da177e4SLinus Torvalds flag aSign;
18331da177e4SLinus Torvalds int16 aExp;
18341da177e4SLinus Torvalds bits64 aSig;
18351da177e4SLinus Torvalds
18361da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
18371da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
18381da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
18391da177e4SLinus Torvalds if ( aExp == 0x7FF ) {
18401da177e4SLinus Torvalds if ( aSig ) return commonNaNToFloatx80( float64ToCommonNaN( a ) );
18411da177e4SLinus Torvalds return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
18421da177e4SLinus Torvalds }
18431da177e4SLinus Torvalds if ( aExp == 0 ) {
18441da177e4SLinus Torvalds if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 );
18451da177e4SLinus Torvalds normalizeFloat64Subnormal( aSig, &aExp, &aSig );
18461da177e4SLinus Torvalds }
18471da177e4SLinus Torvalds return
18481da177e4SLinus Torvalds packFloatx80(
18491da177e4SLinus Torvalds aSign, aExp + 0x3C00, ( aSig | LIT64( 0x0010000000000000 ) )<<11 );
18501da177e4SLinus Torvalds
18511da177e4SLinus Torvalds }
18521da177e4SLinus Torvalds
18531da177e4SLinus Torvalds #endif
18541da177e4SLinus Torvalds
18551da177e4SLinus Torvalds /*
18561da177e4SLinus Torvalds -------------------------------------------------------------------------------
18571da177e4SLinus Torvalds Rounds the double-precision floating-point value `a' to an integer, and
18581da177e4SLinus Torvalds returns the result as a double-precision floating-point value. The
18591da177e4SLinus Torvalds operation is performed according to the IEC/IEEE Standard for Binary
18601da177e4SLinus Torvalds Floating-point Arithmetic.
18611da177e4SLinus Torvalds -------------------------------------------------------------------------------
18621da177e4SLinus Torvalds */
float64_round_to_int(struct roundingData * roundData,float64 a)1863f148af25SRichard Purdie float64 float64_round_to_int( struct roundingData *roundData, float64 a )
18641da177e4SLinus Torvalds {
18651da177e4SLinus Torvalds flag aSign;
18661da177e4SLinus Torvalds int16 aExp;
18671da177e4SLinus Torvalds bits64 lastBitMask, roundBitsMask;
18681da177e4SLinus Torvalds int8 roundingMode;
18691da177e4SLinus Torvalds float64 z;
18701da177e4SLinus Torvalds
18711da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
18721da177e4SLinus Torvalds if ( 0x433 <= aExp ) {
18731da177e4SLinus Torvalds if ( ( aExp == 0x7FF ) && extractFloat64Frac( a ) ) {
18741da177e4SLinus Torvalds return propagateFloat64NaN( a, a );
18751da177e4SLinus Torvalds }
18761da177e4SLinus Torvalds return a;
18771da177e4SLinus Torvalds }
18781da177e4SLinus Torvalds if ( aExp <= 0x3FE ) {
18791da177e4SLinus Torvalds if ( (bits64) ( a<<1 ) == 0 ) return a;
1880f148af25SRichard Purdie roundData->exception |= float_flag_inexact;
18811da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
1882f148af25SRichard Purdie switch ( roundData->mode ) {
18831da177e4SLinus Torvalds case float_round_nearest_even:
18841da177e4SLinus Torvalds if ( ( aExp == 0x3FE ) && extractFloat64Frac( a ) ) {
18851da177e4SLinus Torvalds return packFloat64( aSign, 0x3FF, 0 );
18861da177e4SLinus Torvalds }
18871da177e4SLinus Torvalds break;
18881da177e4SLinus Torvalds case float_round_down:
18891da177e4SLinus Torvalds return aSign ? LIT64( 0xBFF0000000000000 ) : 0;
18901da177e4SLinus Torvalds case float_round_up:
18911da177e4SLinus Torvalds return
18921da177e4SLinus Torvalds aSign ? LIT64( 0x8000000000000000 ) : LIT64( 0x3FF0000000000000 );
18931da177e4SLinus Torvalds }
18941da177e4SLinus Torvalds return packFloat64( aSign, 0, 0 );
18951da177e4SLinus Torvalds }
18961da177e4SLinus Torvalds lastBitMask = 1;
18971da177e4SLinus Torvalds lastBitMask <<= 0x433 - aExp;
18981da177e4SLinus Torvalds roundBitsMask = lastBitMask - 1;
18991da177e4SLinus Torvalds z = a;
1900f148af25SRichard Purdie roundingMode = roundData->mode;
19011da177e4SLinus Torvalds if ( roundingMode == float_round_nearest_even ) {
19021da177e4SLinus Torvalds z += lastBitMask>>1;
19031da177e4SLinus Torvalds if ( ( z & roundBitsMask ) == 0 ) z &= ~ lastBitMask;
19041da177e4SLinus Torvalds }
19051da177e4SLinus Torvalds else if ( roundingMode != float_round_to_zero ) {
19061da177e4SLinus Torvalds if ( extractFloat64Sign( z ) ^ ( roundingMode == float_round_up ) ) {
19071da177e4SLinus Torvalds z += roundBitsMask;
19081da177e4SLinus Torvalds }
19091da177e4SLinus Torvalds }
19101da177e4SLinus Torvalds z &= ~ roundBitsMask;
1911f148af25SRichard Purdie if ( z != a ) roundData->exception |= float_flag_inexact;
19121da177e4SLinus Torvalds return z;
19131da177e4SLinus Torvalds
19141da177e4SLinus Torvalds }
19151da177e4SLinus Torvalds
19161da177e4SLinus Torvalds /*
19171da177e4SLinus Torvalds -------------------------------------------------------------------------------
19181da177e4SLinus Torvalds Returns the result of adding the absolute values of the double-precision
19191da177e4SLinus Torvalds floating-point values `a' and `b'. If `zSign' is true, the sum is negated
19201da177e4SLinus Torvalds before being returned. `zSign' is ignored if the result is a NaN. The
19211da177e4SLinus Torvalds addition is performed according to the IEC/IEEE Standard for Binary
19221da177e4SLinus Torvalds Floating-point Arithmetic.
19231da177e4SLinus Torvalds -------------------------------------------------------------------------------
19241da177e4SLinus Torvalds */
addFloat64Sigs(struct roundingData * roundData,float64 a,float64 b,flag zSign)1925f148af25SRichard Purdie static float64 addFloat64Sigs( struct roundingData *roundData, float64 a, float64 b, flag zSign )
19261da177e4SLinus Torvalds {
19271da177e4SLinus Torvalds int16 aExp, bExp, zExp;
19281da177e4SLinus Torvalds bits64 aSig, bSig, zSig;
19291da177e4SLinus Torvalds int16 expDiff;
19301da177e4SLinus Torvalds
19311da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
19321da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
19331da177e4SLinus Torvalds bSig = extractFloat64Frac( b );
19341da177e4SLinus Torvalds bExp = extractFloat64Exp( b );
19351da177e4SLinus Torvalds expDiff = aExp - bExp;
19361da177e4SLinus Torvalds aSig <<= 9;
19371da177e4SLinus Torvalds bSig <<= 9;
19381da177e4SLinus Torvalds if ( 0 < expDiff ) {
19391da177e4SLinus Torvalds if ( aExp == 0x7FF ) {
19401da177e4SLinus Torvalds if ( aSig ) return propagateFloat64NaN( a, b );
19411da177e4SLinus Torvalds return a;
19421da177e4SLinus Torvalds }
19431da177e4SLinus Torvalds if ( bExp == 0 ) {
19441da177e4SLinus Torvalds --expDiff;
19451da177e4SLinus Torvalds }
19461da177e4SLinus Torvalds else {
19471da177e4SLinus Torvalds bSig |= LIT64( 0x2000000000000000 );
19481da177e4SLinus Torvalds }
19491da177e4SLinus Torvalds shift64RightJamming( bSig, expDiff, &bSig );
19501da177e4SLinus Torvalds zExp = aExp;
19511da177e4SLinus Torvalds }
19521da177e4SLinus Torvalds else if ( expDiff < 0 ) {
19531da177e4SLinus Torvalds if ( bExp == 0x7FF ) {
19541da177e4SLinus Torvalds if ( bSig ) return propagateFloat64NaN( a, b );
19551da177e4SLinus Torvalds return packFloat64( zSign, 0x7FF, 0 );
19561da177e4SLinus Torvalds }
19571da177e4SLinus Torvalds if ( aExp == 0 ) {
19581da177e4SLinus Torvalds ++expDiff;
19591da177e4SLinus Torvalds }
19601da177e4SLinus Torvalds else {
19611da177e4SLinus Torvalds aSig |= LIT64( 0x2000000000000000 );
19621da177e4SLinus Torvalds }
19631da177e4SLinus Torvalds shift64RightJamming( aSig, - expDiff, &aSig );
19641da177e4SLinus Torvalds zExp = bExp;
19651da177e4SLinus Torvalds }
19661da177e4SLinus Torvalds else {
19671da177e4SLinus Torvalds if ( aExp == 0x7FF ) {
19681da177e4SLinus Torvalds if ( aSig | bSig ) return propagateFloat64NaN( a, b );
19691da177e4SLinus Torvalds return a;
19701da177e4SLinus Torvalds }
19711da177e4SLinus Torvalds if ( aExp == 0 ) return packFloat64( zSign, 0, ( aSig + bSig )>>9 );
19721da177e4SLinus Torvalds zSig = LIT64( 0x4000000000000000 ) + aSig + bSig;
19731da177e4SLinus Torvalds zExp = aExp;
19741da177e4SLinus Torvalds goto roundAndPack;
19751da177e4SLinus Torvalds }
19761da177e4SLinus Torvalds aSig |= LIT64( 0x2000000000000000 );
19771da177e4SLinus Torvalds zSig = ( aSig + bSig )<<1;
19781da177e4SLinus Torvalds --zExp;
19791da177e4SLinus Torvalds if ( (sbits64) zSig < 0 ) {
19801da177e4SLinus Torvalds zSig = aSig + bSig;
19811da177e4SLinus Torvalds ++zExp;
19821da177e4SLinus Torvalds }
19831da177e4SLinus Torvalds roundAndPack:
1984f148af25SRichard Purdie return roundAndPackFloat64( roundData, zSign, zExp, zSig );
19851da177e4SLinus Torvalds
19861da177e4SLinus Torvalds }
19871da177e4SLinus Torvalds
19881da177e4SLinus Torvalds /*
19891da177e4SLinus Torvalds -------------------------------------------------------------------------------
19901da177e4SLinus Torvalds Returns the result of subtracting the absolute values of the double-
19911da177e4SLinus Torvalds precision floating-point values `a' and `b'. If `zSign' is true, the
19921da177e4SLinus Torvalds difference is negated before being returned. `zSign' is ignored if the
19931da177e4SLinus Torvalds result is a NaN. The subtraction is performed according to the IEC/IEEE
19941da177e4SLinus Torvalds Standard for Binary Floating-point Arithmetic.
19951da177e4SLinus Torvalds -------------------------------------------------------------------------------
19961da177e4SLinus Torvalds */
subFloat64Sigs(struct roundingData * roundData,float64 a,float64 b,flag zSign)1997f148af25SRichard Purdie static float64 subFloat64Sigs( struct roundingData *roundData, float64 a, float64 b, flag zSign )
19981da177e4SLinus Torvalds {
19991da177e4SLinus Torvalds int16 aExp, bExp, zExp;
20001da177e4SLinus Torvalds bits64 aSig, bSig, zSig;
20011da177e4SLinus Torvalds int16 expDiff;
20021da177e4SLinus Torvalds
20031da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
20041da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
20051da177e4SLinus Torvalds bSig = extractFloat64Frac( b );
20061da177e4SLinus Torvalds bExp = extractFloat64Exp( b );
20071da177e4SLinus Torvalds expDiff = aExp - bExp;
20081da177e4SLinus Torvalds aSig <<= 10;
20091da177e4SLinus Torvalds bSig <<= 10;
20101da177e4SLinus Torvalds if ( 0 < expDiff ) goto aExpBigger;
20111da177e4SLinus Torvalds if ( expDiff < 0 ) goto bExpBigger;
20121da177e4SLinus Torvalds if ( aExp == 0x7FF ) {
20131da177e4SLinus Torvalds if ( aSig | bSig ) return propagateFloat64NaN( a, b );
2014f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
20151da177e4SLinus Torvalds return float64_default_nan;
20161da177e4SLinus Torvalds }
20171da177e4SLinus Torvalds if ( aExp == 0 ) {
20181da177e4SLinus Torvalds aExp = 1;
20191da177e4SLinus Torvalds bExp = 1;
20201da177e4SLinus Torvalds }
20211da177e4SLinus Torvalds if ( bSig < aSig ) goto aBigger;
20221da177e4SLinus Torvalds if ( aSig < bSig ) goto bBigger;
2023f148af25SRichard Purdie return packFloat64( roundData->mode == float_round_down, 0, 0 );
20241da177e4SLinus Torvalds bExpBigger:
20251da177e4SLinus Torvalds if ( bExp == 0x7FF ) {
20261da177e4SLinus Torvalds if ( bSig ) return propagateFloat64NaN( a, b );
20271da177e4SLinus Torvalds return packFloat64( zSign ^ 1, 0x7FF, 0 );
20281da177e4SLinus Torvalds }
20291da177e4SLinus Torvalds if ( aExp == 0 ) {
20301da177e4SLinus Torvalds ++expDiff;
20311da177e4SLinus Torvalds }
20321da177e4SLinus Torvalds else {
20331da177e4SLinus Torvalds aSig |= LIT64( 0x4000000000000000 );
20341da177e4SLinus Torvalds }
20351da177e4SLinus Torvalds shift64RightJamming( aSig, - expDiff, &aSig );
20361da177e4SLinus Torvalds bSig |= LIT64( 0x4000000000000000 );
20371da177e4SLinus Torvalds bBigger:
20381da177e4SLinus Torvalds zSig = bSig - aSig;
20391da177e4SLinus Torvalds zExp = bExp;
20401da177e4SLinus Torvalds zSign ^= 1;
20411da177e4SLinus Torvalds goto normalizeRoundAndPack;
20421da177e4SLinus Torvalds aExpBigger:
20431da177e4SLinus Torvalds if ( aExp == 0x7FF ) {
20441da177e4SLinus Torvalds if ( aSig ) return propagateFloat64NaN( a, b );
20451da177e4SLinus Torvalds return a;
20461da177e4SLinus Torvalds }
20471da177e4SLinus Torvalds if ( bExp == 0 ) {
20481da177e4SLinus Torvalds --expDiff;
20491da177e4SLinus Torvalds }
20501da177e4SLinus Torvalds else {
20511da177e4SLinus Torvalds bSig |= LIT64( 0x4000000000000000 );
20521da177e4SLinus Torvalds }
20531da177e4SLinus Torvalds shift64RightJamming( bSig, expDiff, &bSig );
20541da177e4SLinus Torvalds aSig |= LIT64( 0x4000000000000000 );
20551da177e4SLinus Torvalds aBigger:
20561da177e4SLinus Torvalds zSig = aSig - bSig;
20571da177e4SLinus Torvalds zExp = aExp;
20581da177e4SLinus Torvalds normalizeRoundAndPack:
20591da177e4SLinus Torvalds --zExp;
2060f148af25SRichard Purdie return normalizeRoundAndPackFloat64( roundData, zSign, zExp, zSig );
20611da177e4SLinus Torvalds
20621da177e4SLinus Torvalds }
20631da177e4SLinus Torvalds
20641da177e4SLinus Torvalds /*
20651da177e4SLinus Torvalds -------------------------------------------------------------------------------
20661da177e4SLinus Torvalds Returns the result of adding the double-precision floating-point values `a'
20671da177e4SLinus Torvalds and `b'. The operation is performed according to the IEC/IEEE Standard for
20681da177e4SLinus Torvalds Binary Floating-point Arithmetic.
20691da177e4SLinus Torvalds -------------------------------------------------------------------------------
20701da177e4SLinus Torvalds */
float64_add(struct roundingData * roundData,float64 a,float64 b)2071f148af25SRichard Purdie float64 float64_add( struct roundingData *roundData, float64 a, float64 b )
20721da177e4SLinus Torvalds {
20731da177e4SLinus Torvalds flag aSign, bSign;
20741da177e4SLinus Torvalds
20751da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
20761da177e4SLinus Torvalds bSign = extractFloat64Sign( b );
20771da177e4SLinus Torvalds if ( aSign == bSign ) {
2078f148af25SRichard Purdie return addFloat64Sigs( roundData, a, b, aSign );
20791da177e4SLinus Torvalds }
20801da177e4SLinus Torvalds else {
2081f148af25SRichard Purdie return subFloat64Sigs( roundData, a, b, aSign );
20821da177e4SLinus Torvalds }
20831da177e4SLinus Torvalds
20841da177e4SLinus Torvalds }
20851da177e4SLinus Torvalds
20861da177e4SLinus Torvalds /*
20871da177e4SLinus Torvalds -------------------------------------------------------------------------------
20881da177e4SLinus Torvalds Returns the result of subtracting the double-precision floating-point values
20891da177e4SLinus Torvalds `a' and `b'. The operation is performed according to the IEC/IEEE Standard
20901da177e4SLinus Torvalds for Binary Floating-point Arithmetic.
20911da177e4SLinus Torvalds -------------------------------------------------------------------------------
20921da177e4SLinus Torvalds */
float64_sub(struct roundingData * roundData,float64 a,float64 b)2093f148af25SRichard Purdie float64 float64_sub( struct roundingData *roundData, float64 a, float64 b )
20941da177e4SLinus Torvalds {
20951da177e4SLinus Torvalds flag aSign, bSign;
20961da177e4SLinus Torvalds
20971da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
20981da177e4SLinus Torvalds bSign = extractFloat64Sign( b );
20991da177e4SLinus Torvalds if ( aSign == bSign ) {
2100f148af25SRichard Purdie return subFloat64Sigs( roundData, a, b, aSign );
21011da177e4SLinus Torvalds }
21021da177e4SLinus Torvalds else {
2103f148af25SRichard Purdie return addFloat64Sigs( roundData, a, b, aSign );
21041da177e4SLinus Torvalds }
21051da177e4SLinus Torvalds
21061da177e4SLinus Torvalds }
21071da177e4SLinus Torvalds
21081da177e4SLinus Torvalds /*
21091da177e4SLinus Torvalds -------------------------------------------------------------------------------
21101da177e4SLinus Torvalds Returns the result of multiplying the double-precision floating-point values
21111da177e4SLinus Torvalds `a' and `b'. The operation is performed according to the IEC/IEEE Standard
21121da177e4SLinus Torvalds for Binary Floating-point Arithmetic.
21131da177e4SLinus Torvalds -------------------------------------------------------------------------------
21141da177e4SLinus Torvalds */
float64_mul(struct roundingData * roundData,float64 a,float64 b)2115f148af25SRichard Purdie float64 float64_mul( struct roundingData *roundData, float64 a, float64 b )
21161da177e4SLinus Torvalds {
21171da177e4SLinus Torvalds flag aSign, bSign, zSign;
21181da177e4SLinus Torvalds int16 aExp, bExp, zExp;
21191da177e4SLinus Torvalds bits64 aSig, bSig, zSig0, zSig1;
21201da177e4SLinus Torvalds
21211da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
21221da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
21231da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
21241da177e4SLinus Torvalds bSig = extractFloat64Frac( b );
21251da177e4SLinus Torvalds bExp = extractFloat64Exp( b );
21261da177e4SLinus Torvalds bSign = extractFloat64Sign( b );
21271da177e4SLinus Torvalds zSign = aSign ^ bSign;
21281da177e4SLinus Torvalds if ( aExp == 0x7FF ) {
21291da177e4SLinus Torvalds if ( aSig || ( ( bExp == 0x7FF ) && bSig ) ) {
21301da177e4SLinus Torvalds return propagateFloat64NaN( a, b );
21311da177e4SLinus Torvalds }
21321da177e4SLinus Torvalds if ( ( bExp | bSig ) == 0 ) {
2133f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
21341da177e4SLinus Torvalds return float64_default_nan;
21351da177e4SLinus Torvalds }
21361da177e4SLinus Torvalds return packFloat64( zSign, 0x7FF, 0 );
21371da177e4SLinus Torvalds }
21381da177e4SLinus Torvalds if ( bExp == 0x7FF ) {
21391da177e4SLinus Torvalds if ( bSig ) return propagateFloat64NaN( a, b );
21401da177e4SLinus Torvalds if ( ( aExp | aSig ) == 0 ) {
2141f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
21421da177e4SLinus Torvalds return float64_default_nan;
21431da177e4SLinus Torvalds }
21441da177e4SLinus Torvalds return packFloat64( zSign, 0x7FF, 0 );
21451da177e4SLinus Torvalds }
21461da177e4SLinus Torvalds if ( aExp == 0 ) {
21471da177e4SLinus Torvalds if ( aSig == 0 ) return packFloat64( zSign, 0, 0 );
21481da177e4SLinus Torvalds normalizeFloat64Subnormal( aSig, &aExp, &aSig );
21491da177e4SLinus Torvalds }
21501da177e4SLinus Torvalds if ( bExp == 0 ) {
21511da177e4SLinus Torvalds if ( bSig == 0 ) return packFloat64( zSign, 0, 0 );
21521da177e4SLinus Torvalds normalizeFloat64Subnormal( bSig, &bExp, &bSig );
21531da177e4SLinus Torvalds }
21541da177e4SLinus Torvalds zExp = aExp + bExp - 0x3FF;
21551da177e4SLinus Torvalds aSig = ( aSig | LIT64( 0x0010000000000000 ) )<<10;
21561da177e4SLinus Torvalds bSig = ( bSig | LIT64( 0x0010000000000000 ) )<<11;
21571da177e4SLinus Torvalds mul64To128( aSig, bSig, &zSig0, &zSig1 );
21581da177e4SLinus Torvalds zSig0 |= ( zSig1 != 0 );
21591da177e4SLinus Torvalds if ( 0 <= (sbits64) ( zSig0<<1 ) ) {
21601da177e4SLinus Torvalds zSig0 <<= 1;
21611da177e4SLinus Torvalds --zExp;
21621da177e4SLinus Torvalds }
2163f148af25SRichard Purdie return roundAndPackFloat64( roundData, zSign, zExp, zSig0 );
21641da177e4SLinus Torvalds
21651da177e4SLinus Torvalds }
21661da177e4SLinus Torvalds
21671da177e4SLinus Torvalds /*
21681da177e4SLinus Torvalds -------------------------------------------------------------------------------
21691da177e4SLinus Torvalds Returns the result of dividing the double-precision floating-point value `a'
21701da177e4SLinus Torvalds by the corresponding value `b'. The operation is performed according to
21711da177e4SLinus Torvalds the IEC/IEEE Standard for Binary Floating-point Arithmetic.
21721da177e4SLinus Torvalds -------------------------------------------------------------------------------
21731da177e4SLinus Torvalds */
float64_div(struct roundingData * roundData,float64 a,float64 b)2174f148af25SRichard Purdie float64 float64_div( struct roundingData *roundData, float64 a, float64 b )
21751da177e4SLinus Torvalds {
21761da177e4SLinus Torvalds flag aSign, bSign, zSign;
21771da177e4SLinus Torvalds int16 aExp, bExp, zExp;
21781da177e4SLinus Torvalds bits64 aSig, bSig, zSig;
21791da177e4SLinus Torvalds bits64 rem0, rem1;
21801da177e4SLinus Torvalds bits64 term0, term1;
21811da177e4SLinus Torvalds
21821da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
21831da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
21841da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
21851da177e4SLinus Torvalds bSig = extractFloat64Frac( b );
21861da177e4SLinus Torvalds bExp = extractFloat64Exp( b );
21871da177e4SLinus Torvalds bSign = extractFloat64Sign( b );
21881da177e4SLinus Torvalds zSign = aSign ^ bSign;
21891da177e4SLinus Torvalds if ( aExp == 0x7FF ) {
21901da177e4SLinus Torvalds if ( aSig ) return propagateFloat64NaN( a, b );
21911da177e4SLinus Torvalds if ( bExp == 0x7FF ) {
21921da177e4SLinus Torvalds if ( bSig ) return propagateFloat64NaN( a, b );
2193f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
21941da177e4SLinus Torvalds return float64_default_nan;
21951da177e4SLinus Torvalds }
21961da177e4SLinus Torvalds return packFloat64( zSign, 0x7FF, 0 );
21971da177e4SLinus Torvalds }
21981da177e4SLinus Torvalds if ( bExp == 0x7FF ) {
21991da177e4SLinus Torvalds if ( bSig ) return propagateFloat64NaN( a, b );
22001da177e4SLinus Torvalds return packFloat64( zSign, 0, 0 );
22011da177e4SLinus Torvalds }
22021da177e4SLinus Torvalds if ( bExp == 0 ) {
22031da177e4SLinus Torvalds if ( bSig == 0 ) {
22041da177e4SLinus Torvalds if ( ( aExp | aSig ) == 0 ) {
2205f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
22061da177e4SLinus Torvalds return float64_default_nan;
22071da177e4SLinus Torvalds }
2208f148af25SRichard Purdie roundData->exception |= float_flag_divbyzero;
22091da177e4SLinus Torvalds return packFloat64( zSign, 0x7FF, 0 );
22101da177e4SLinus Torvalds }
22111da177e4SLinus Torvalds normalizeFloat64Subnormal( bSig, &bExp, &bSig );
22121da177e4SLinus Torvalds }
22131da177e4SLinus Torvalds if ( aExp == 0 ) {
22141da177e4SLinus Torvalds if ( aSig == 0 ) return packFloat64( zSign, 0, 0 );
22151da177e4SLinus Torvalds normalizeFloat64Subnormal( aSig, &aExp, &aSig );
22161da177e4SLinus Torvalds }
22171da177e4SLinus Torvalds zExp = aExp - bExp + 0x3FD;
22181da177e4SLinus Torvalds aSig = ( aSig | LIT64( 0x0010000000000000 ) )<<10;
22191da177e4SLinus Torvalds bSig = ( bSig | LIT64( 0x0010000000000000 ) )<<11;
22201da177e4SLinus Torvalds if ( bSig <= ( aSig + aSig ) ) {
22211da177e4SLinus Torvalds aSig >>= 1;
22221da177e4SLinus Torvalds ++zExp;
22231da177e4SLinus Torvalds }
22241da177e4SLinus Torvalds zSig = estimateDiv128To64( aSig, 0, bSig );
22251da177e4SLinus Torvalds if ( ( zSig & 0x1FF ) <= 2 ) {
22261da177e4SLinus Torvalds mul64To128( bSig, zSig, &term0, &term1 );
22271da177e4SLinus Torvalds sub128( aSig, 0, term0, term1, &rem0, &rem1 );
22281da177e4SLinus Torvalds while ( (sbits64) rem0 < 0 ) {
22291da177e4SLinus Torvalds --zSig;
22301da177e4SLinus Torvalds add128( rem0, rem1, 0, bSig, &rem0, &rem1 );
22311da177e4SLinus Torvalds }
22321da177e4SLinus Torvalds zSig |= ( rem1 != 0 );
22331da177e4SLinus Torvalds }
2234f148af25SRichard Purdie return roundAndPackFloat64( roundData, zSign, zExp, zSig );
22351da177e4SLinus Torvalds
22361da177e4SLinus Torvalds }
22371da177e4SLinus Torvalds
22381da177e4SLinus Torvalds /*
22391da177e4SLinus Torvalds -------------------------------------------------------------------------------
22401da177e4SLinus Torvalds Returns the remainder of the double-precision floating-point value `a'
22411da177e4SLinus Torvalds with respect to the corresponding value `b'. The operation is performed
22421da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
22431da177e4SLinus Torvalds -------------------------------------------------------------------------------
22441da177e4SLinus Torvalds */
float64_rem(struct roundingData * roundData,float64 a,float64 b)2245f148af25SRichard Purdie float64 float64_rem( struct roundingData *roundData, float64 a, float64 b )
22461da177e4SLinus Torvalds {
22471da177e4SLinus Torvalds flag aSign, bSign, zSign;
22481da177e4SLinus Torvalds int16 aExp, bExp, expDiff;
22491da177e4SLinus Torvalds bits64 aSig, bSig;
22501da177e4SLinus Torvalds bits64 q, alternateASig;
22511da177e4SLinus Torvalds sbits64 sigMean;
22521da177e4SLinus Torvalds
22531da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
22541da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
22551da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
22561da177e4SLinus Torvalds bSig = extractFloat64Frac( b );
22571da177e4SLinus Torvalds bExp = extractFloat64Exp( b );
22581da177e4SLinus Torvalds bSign = extractFloat64Sign( b );
22591da177e4SLinus Torvalds if ( aExp == 0x7FF ) {
22601da177e4SLinus Torvalds if ( aSig || ( ( bExp == 0x7FF ) && bSig ) ) {
22611da177e4SLinus Torvalds return propagateFloat64NaN( a, b );
22621da177e4SLinus Torvalds }
2263f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
22641da177e4SLinus Torvalds return float64_default_nan;
22651da177e4SLinus Torvalds }
22661da177e4SLinus Torvalds if ( bExp == 0x7FF ) {
22671da177e4SLinus Torvalds if ( bSig ) return propagateFloat64NaN( a, b );
22681da177e4SLinus Torvalds return a;
22691da177e4SLinus Torvalds }
22701da177e4SLinus Torvalds if ( bExp == 0 ) {
22711da177e4SLinus Torvalds if ( bSig == 0 ) {
2272f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
22731da177e4SLinus Torvalds return float64_default_nan;
22741da177e4SLinus Torvalds }
22751da177e4SLinus Torvalds normalizeFloat64Subnormal( bSig, &bExp, &bSig );
22761da177e4SLinus Torvalds }
22771da177e4SLinus Torvalds if ( aExp == 0 ) {
22781da177e4SLinus Torvalds if ( aSig == 0 ) return a;
22791da177e4SLinus Torvalds normalizeFloat64Subnormal( aSig, &aExp, &aSig );
22801da177e4SLinus Torvalds }
22811da177e4SLinus Torvalds expDiff = aExp - bExp;
22821da177e4SLinus Torvalds aSig = ( aSig | LIT64( 0x0010000000000000 ) )<<11;
22831da177e4SLinus Torvalds bSig = ( bSig | LIT64( 0x0010000000000000 ) )<<11;
22841da177e4SLinus Torvalds if ( expDiff < 0 ) {
22851da177e4SLinus Torvalds if ( expDiff < -1 ) return a;
22861da177e4SLinus Torvalds aSig >>= 1;
22871da177e4SLinus Torvalds }
22881da177e4SLinus Torvalds q = ( bSig <= aSig );
22891da177e4SLinus Torvalds if ( q ) aSig -= bSig;
22901da177e4SLinus Torvalds expDiff -= 64;
22911da177e4SLinus Torvalds while ( 0 < expDiff ) {
22921da177e4SLinus Torvalds q = estimateDiv128To64( aSig, 0, bSig );
22931da177e4SLinus Torvalds q = ( 2 < q ) ? q - 2 : 0;
22941da177e4SLinus Torvalds aSig = - ( ( bSig>>2 ) * q );
22951da177e4SLinus Torvalds expDiff -= 62;
22961da177e4SLinus Torvalds }
22971da177e4SLinus Torvalds expDiff += 64;
22981da177e4SLinus Torvalds if ( 0 < expDiff ) {
22991da177e4SLinus Torvalds q = estimateDiv128To64( aSig, 0, bSig );
23001da177e4SLinus Torvalds q = ( 2 < q ) ? q - 2 : 0;
23011da177e4SLinus Torvalds q >>= 64 - expDiff;
23021da177e4SLinus Torvalds bSig >>= 2;
23031da177e4SLinus Torvalds aSig = ( ( aSig>>1 )<<( expDiff - 1 ) ) - bSig * q;
23041da177e4SLinus Torvalds }
23051da177e4SLinus Torvalds else {
23061da177e4SLinus Torvalds aSig >>= 2;
23071da177e4SLinus Torvalds bSig >>= 2;
23081da177e4SLinus Torvalds }
23091da177e4SLinus Torvalds do {
23101da177e4SLinus Torvalds alternateASig = aSig;
23111da177e4SLinus Torvalds ++q;
23121da177e4SLinus Torvalds aSig -= bSig;
23131da177e4SLinus Torvalds } while ( 0 <= (sbits64) aSig );
23141da177e4SLinus Torvalds sigMean = aSig + alternateASig;
23151da177e4SLinus Torvalds if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) {
23161da177e4SLinus Torvalds aSig = alternateASig;
23171da177e4SLinus Torvalds }
23181da177e4SLinus Torvalds zSign = ( (sbits64) aSig < 0 );
23191da177e4SLinus Torvalds if ( zSign ) aSig = - aSig;
2320f148af25SRichard Purdie return normalizeRoundAndPackFloat64( roundData, aSign ^ zSign, bExp, aSig );
23211da177e4SLinus Torvalds
23221da177e4SLinus Torvalds }
23231da177e4SLinus Torvalds
23241da177e4SLinus Torvalds /*
23251da177e4SLinus Torvalds -------------------------------------------------------------------------------
23261da177e4SLinus Torvalds Returns the square root of the double-precision floating-point value `a'.
23271da177e4SLinus Torvalds The operation is performed according to the IEC/IEEE Standard for Binary
23281da177e4SLinus Torvalds Floating-point Arithmetic.
23291da177e4SLinus Torvalds -------------------------------------------------------------------------------
23301da177e4SLinus Torvalds */
float64_sqrt(struct roundingData * roundData,float64 a)2331f148af25SRichard Purdie float64 float64_sqrt( struct roundingData *roundData, float64 a )
23321da177e4SLinus Torvalds {
23331da177e4SLinus Torvalds flag aSign;
23341da177e4SLinus Torvalds int16 aExp, zExp;
23351da177e4SLinus Torvalds bits64 aSig, zSig;
23361da177e4SLinus Torvalds bits64 rem0, rem1, term0, term1; //, shiftedRem;
23371da177e4SLinus Torvalds //float64 z;
23381da177e4SLinus Torvalds
23391da177e4SLinus Torvalds aSig = extractFloat64Frac( a );
23401da177e4SLinus Torvalds aExp = extractFloat64Exp( a );
23411da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
23421da177e4SLinus Torvalds if ( aExp == 0x7FF ) {
23431da177e4SLinus Torvalds if ( aSig ) return propagateFloat64NaN( a, a );
23441da177e4SLinus Torvalds if ( ! aSign ) return a;
2345f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
23461da177e4SLinus Torvalds return float64_default_nan;
23471da177e4SLinus Torvalds }
23481da177e4SLinus Torvalds if ( aSign ) {
23491da177e4SLinus Torvalds if ( ( aExp | aSig ) == 0 ) return a;
2350f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
23511da177e4SLinus Torvalds return float64_default_nan;
23521da177e4SLinus Torvalds }
23531da177e4SLinus Torvalds if ( aExp == 0 ) {
23541da177e4SLinus Torvalds if ( aSig == 0 ) return 0;
23551da177e4SLinus Torvalds normalizeFloat64Subnormal( aSig, &aExp, &aSig );
23561da177e4SLinus Torvalds }
23571da177e4SLinus Torvalds zExp = ( ( aExp - 0x3FF )>>1 ) + 0x3FE;
23581da177e4SLinus Torvalds aSig |= LIT64( 0x0010000000000000 );
23591da177e4SLinus Torvalds zSig = estimateSqrt32( aExp, aSig>>21 );
23601da177e4SLinus Torvalds zSig <<= 31;
23611da177e4SLinus Torvalds aSig <<= 9 - ( aExp & 1 );
23621da177e4SLinus Torvalds zSig = estimateDiv128To64( aSig, 0, zSig ) + zSig + 2;
23631da177e4SLinus Torvalds if ( ( zSig & 0x3FF ) <= 5 ) {
23641da177e4SLinus Torvalds if ( zSig < 2 ) {
23651da177e4SLinus Torvalds zSig = LIT64( 0xFFFFFFFFFFFFFFFF );
23661da177e4SLinus Torvalds }
23671da177e4SLinus Torvalds else {
23681da177e4SLinus Torvalds aSig <<= 2;
23691da177e4SLinus Torvalds mul64To128( zSig, zSig, &term0, &term1 );
23701da177e4SLinus Torvalds sub128( aSig, 0, term0, term1, &rem0, &rem1 );
23711da177e4SLinus Torvalds while ( (sbits64) rem0 < 0 ) {
23721da177e4SLinus Torvalds --zSig;
23731da177e4SLinus Torvalds shortShift128Left( 0, zSig, 1, &term0, &term1 );
23741da177e4SLinus Torvalds term1 |= 1;
23751da177e4SLinus Torvalds add128( rem0, rem1, term0, term1, &rem0, &rem1 );
23761da177e4SLinus Torvalds }
23771da177e4SLinus Torvalds zSig |= ( ( rem0 | rem1 ) != 0 );
23781da177e4SLinus Torvalds }
23791da177e4SLinus Torvalds }
23801da177e4SLinus Torvalds shift64RightJamming( zSig, 1, &zSig );
2381f148af25SRichard Purdie return roundAndPackFloat64( roundData, 0, zExp, zSig );
23821da177e4SLinus Torvalds
23831da177e4SLinus Torvalds }
23841da177e4SLinus Torvalds
23851da177e4SLinus Torvalds /*
23861da177e4SLinus Torvalds -------------------------------------------------------------------------------
23871da177e4SLinus Torvalds Returns 1 if the double-precision floating-point value `a' is equal to the
23881da177e4SLinus Torvalds corresponding value `b', and 0 otherwise. The comparison is performed
23891da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
23901da177e4SLinus Torvalds -------------------------------------------------------------------------------
23911da177e4SLinus Torvalds */
float64_eq(float64 a,float64 b)23921da177e4SLinus Torvalds flag float64_eq( float64 a, float64 b )
23931da177e4SLinus Torvalds {
23941da177e4SLinus Torvalds
23951da177e4SLinus Torvalds if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
23961da177e4SLinus Torvalds || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
23971da177e4SLinus Torvalds ) {
23981da177e4SLinus Torvalds if ( float64_is_signaling_nan( a ) || float64_is_signaling_nan( b ) ) {
23991da177e4SLinus Torvalds float_raise( float_flag_invalid );
24001da177e4SLinus Torvalds }
24011da177e4SLinus Torvalds return 0;
24021da177e4SLinus Torvalds }
24031da177e4SLinus Torvalds return ( a == b ) || ( (bits64) ( ( a | b )<<1 ) == 0 );
24041da177e4SLinus Torvalds
24051da177e4SLinus Torvalds }
24061da177e4SLinus Torvalds
24071da177e4SLinus Torvalds /*
24081da177e4SLinus Torvalds -------------------------------------------------------------------------------
24091da177e4SLinus Torvalds Returns 1 if the double-precision floating-point value `a' is less than or
24101da177e4SLinus Torvalds equal to the corresponding value `b', and 0 otherwise. The comparison is
24111da177e4SLinus Torvalds performed according to the IEC/IEEE Standard for Binary Floating-point
24121da177e4SLinus Torvalds Arithmetic.
24131da177e4SLinus Torvalds -------------------------------------------------------------------------------
24141da177e4SLinus Torvalds */
float64_le(float64 a,float64 b)24151da177e4SLinus Torvalds flag float64_le( float64 a, float64 b )
24161da177e4SLinus Torvalds {
24171da177e4SLinus Torvalds flag aSign, bSign;
24181da177e4SLinus Torvalds
24191da177e4SLinus Torvalds if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
24201da177e4SLinus Torvalds || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
24211da177e4SLinus Torvalds ) {
24221da177e4SLinus Torvalds float_raise( float_flag_invalid );
24231da177e4SLinus Torvalds return 0;
24241da177e4SLinus Torvalds }
24251da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
24261da177e4SLinus Torvalds bSign = extractFloat64Sign( b );
24271da177e4SLinus Torvalds if ( aSign != bSign ) return aSign || ( (bits64) ( ( a | b )<<1 ) == 0 );
24281da177e4SLinus Torvalds return ( a == b ) || ( aSign ^ ( a < b ) );
24291da177e4SLinus Torvalds
24301da177e4SLinus Torvalds }
24311da177e4SLinus Torvalds
24321da177e4SLinus Torvalds /*
24331da177e4SLinus Torvalds -------------------------------------------------------------------------------
24341da177e4SLinus Torvalds Returns 1 if the double-precision floating-point value `a' is less than
24351da177e4SLinus Torvalds the corresponding value `b', and 0 otherwise. The comparison is performed
24361da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
24371da177e4SLinus Torvalds -------------------------------------------------------------------------------
24381da177e4SLinus Torvalds */
float64_lt(float64 a,float64 b)24391da177e4SLinus Torvalds flag float64_lt( float64 a, float64 b )
24401da177e4SLinus Torvalds {
24411da177e4SLinus Torvalds flag aSign, bSign;
24421da177e4SLinus Torvalds
24431da177e4SLinus Torvalds if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
24441da177e4SLinus Torvalds || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
24451da177e4SLinus Torvalds ) {
24461da177e4SLinus Torvalds float_raise( float_flag_invalid );
24471da177e4SLinus Torvalds return 0;
24481da177e4SLinus Torvalds }
24491da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
24501da177e4SLinus Torvalds bSign = extractFloat64Sign( b );
24511da177e4SLinus Torvalds if ( aSign != bSign ) return aSign && ( (bits64) ( ( a | b )<<1 ) != 0 );
24521da177e4SLinus Torvalds return ( a != b ) && ( aSign ^ ( a < b ) );
24531da177e4SLinus Torvalds
24541da177e4SLinus Torvalds }
24551da177e4SLinus Torvalds
24561da177e4SLinus Torvalds /*
24571da177e4SLinus Torvalds -------------------------------------------------------------------------------
24581da177e4SLinus Torvalds Returns 1 if the double-precision floating-point value `a' is equal to the
24591da177e4SLinus Torvalds corresponding value `b', and 0 otherwise. The invalid exception is raised
24601da177e4SLinus Torvalds if either operand is a NaN. Otherwise, the comparison is performed
24611da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
24621da177e4SLinus Torvalds -------------------------------------------------------------------------------
24631da177e4SLinus Torvalds */
float64_eq_signaling(float64 a,float64 b)24641da177e4SLinus Torvalds flag float64_eq_signaling( float64 a, float64 b )
24651da177e4SLinus Torvalds {
24661da177e4SLinus Torvalds
24671da177e4SLinus Torvalds if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
24681da177e4SLinus Torvalds || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
24691da177e4SLinus Torvalds ) {
24701da177e4SLinus Torvalds float_raise( float_flag_invalid );
24711da177e4SLinus Torvalds return 0;
24721da177e4SLinus Torvalds }
24731da177e4SLinus Torvalds return ( a == b ) || ( (bits64) ( ( a | b )<<1 ) == 0 );
24741da177e4SLinus Torvalds
24751da177e4SLinus Torvalds }
24761da177e4SLinus Torvalds
24771da177e4SLinus Torvalds /*
24781da177e4SLinus Torvalds -------------------------------------------------------------------------------
24791da177e4SLinus Torvalds Returns 1 if the double-precision floating-point value `a' is less than or
24801da177e4SLinus Torvalds equal to the corresponding value `b', and 0 otherwise. Quiet NaNs do not
24811da177e4SLinus Torvalds cause an exception. Otherwise, the comparison is performed according to the
24821da177e4SLinus Torvalds IEC/IEEE Standard for Binary Floating-point Arithmetic.
24831da177e4SLinus Torvalds -------------------------------------------------------------------------------
24841da177e4SLinus Torvalds */
float64_le_quiet(float64 a,float64 b)24851da177e4SLinus Torvalds flag float64_le_quiet( float64 a, float64 b )
24861da177e4SLinus Torvalds {
24871da177e4SLinus Torvalds flag aSign, bSign;
24881da177e4SLinus Torvalds //int16 aExp, bExp;
24891da177e4SLinus Torvalds
24901da177e4SLinus Torvalds if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
24911da177e4SLinus Torvalds || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
24921da177e4SLinus Torvalds ) {
249354738e82SRichard Purdie /* Do nothing, even if NaN as we're quiet */
24941da177e4SLinus Torvalds return 0;
24951da177e4SLinus Torvalds }
24961da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
24971da177e4SLinus Torvalds bSign = extractFloat64Sign( b );
24981da177e4SLinus Torvalds if ( aSign != bSign ) return aSign || ( (bits64) ( ( a | b )<<1 ) == 0 );
24991da177e4SLinus Torvalds return ( a == b ) || ( aSign ^ ( a < b ) );
25001da177e4SLinus Torvalds
25011da177e4SLinus Torvalds }
25021da177e4SLinus Torvalds
25031da177e4SLinus Torvalds /*
25041da177e4SLinus Torvalds -------------------------------------------------------------------------------
25051da177e4SLinus Torvalds Returns 1 if the double-precision floating-point value `a' is less than
25061da177e4SLinus Torvalds the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an
25071da177e4SLinus Torvalds exception. Otherwise, the comparison is performed according to the IEC/IEEE
25081da177e4SLinus Torvalds Standard for Binary Floating-point Arithmetic.
25091da177e4SLinus Torvalds -------------------------------------------------------------------------------
25101da177e4SLinus Torvalds */
float64_lt_quiet(float64 a,float64 b)25111da177e4SLinus Torvalds flag float64_lt_quiet( float64 a, float64 b )
25121da177e4SLinus Torvalds {
25131da177e4SLinus Torvalds flag aSign, bSign;
25141da177e4SLinus Torvalds
25151da177e4SLinus Torvalds if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) )
25161da177e4SLinus Torvalds || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) )
25171da177e4SLinus Torvalds ) {
251854738e82SRichard Purdie /* Do nothing, even if NaN as we're quiet */
25191da177e4SLinus Torvalds return 0;
25201da177e4SLinus Torvalds }
25211da177e4SLinus Torvalds aSign = extractFloat64Sign( a );
25221da177e4SLinus Torvalds bSign = extractFloat64Sign( b );
25231da177e4SLinus Torvalds if ( aSign != bSign ) return aSign && ( (bits64) ( ( a | b )<<1 ) != 0 );
25241da177e4SLinus Torvalds return ( a != b ) && ( aSign ^ ( a < b ) );
25251da177e4SLinus Torvalds
25261da177e4SLinus Torvalds }
25271da177e4SLinus Torvalds
25281da177e4SLinus Torvalds #ifdef FLOATX80
25291da177e4SLinus Torvalds
25301da177e4SLinus Torvalds /*
25311da177e4SLinus Torvalds -------------------------------------------------------------------------------
25321da177e4SLinus Torvalds Returns the result of converting the extended double-precision floating-
25331da177e4SLinus Torvalds point value `a' to the 32-bit two's complement integer format. The
25341da177e4SLinus Torvalds conversion is performed according to the IEC/IEEE Standard for Binary
25351da177e4SLinus Torvalds Floating-point Arithmetic---which means in particular that the conversion
25361da177e4SLinus Torvalds is rounded according to the current rounding mode. If `a' is a NaN, the
25371da177e4SLinus Torvalds largest positive integer is returned. Otherwise, if the conversion
25381da177e4SLinus Torvalds overflows, the largest integer with the same sign as `a' is returned.
25391da177e4SLinus Torvalds -------------------------------------------------------------------------------
25401da177e4SLinus Torvalds */
floatx80_to_int32(struct roundingData * roundData,floatx80 a)2541f148af25SRichard Purdie int32 floatx80_to_int32( struct roundingData *roundData, floatx80 a )
25421da177e4SLinus Torvalds {
25431da177e4SLinus Torvalds flag aSign;
25441da177e4SLinus Torvalds int32 aExp, shiftCount;
25451da177e4SLinus Torvalds bits64 aSig;
25461da177e4SLinus Torvalds
25471da177e4SLinus Torvalds aSig = extractFloatx80Frac( a );
25481da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
25491da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
25501da177e4SLinus Torvalds if ( ( aExp == 0x7FFF ) && (bits64) ( aSig<<1 ) ) aSign = 0;
25511da177e4SLinus Torvalds shiftCount = 0x4037 - aExp;
25521da177e4SLinus Torvalds if ( shiftCount <= 0 ) shiftCount = 1;
25531da177e4SLinus Torvalds shift64RightJamming( aSig, shiftCount, &aSig );
2554f148af25SRichard Purdie return roundAndPackInt32( roundData, aSign, aSig );
25551da177e4SLinus Torvalds
25561da177e4SLinus Torvalds }
25571da177e4SLinus Torvalds
25581da177e4SLinus Torvalds /*
25591da177e4SLinus Torvalds -------------------------------------------------------------------------------
25601da177e4SLinus Torvalds Returns the result of converting the extended double-precision floating-
25611da177e4SLinus Torvalds point value `a' to the 32-bit two's complement integer format. The
25621da177e4SLinus Torvalds conversion is performed according to the IEC/IEEE Standard for Binary
25631da177e4SLinus Torvalds Floating-point Arithmetic, except that the conversion is always rounded
25641da177e4SLinus Torvalds toward zero. If `a' is a NaN, the largest positive integer is returned.
25651da177e4SLinus Torvalds Otherwise, if the conversion overflows, the largest integer with the same
25661da177e4SLinus Torvalds sign as `a' is returned.
25671da177e4SLinus Torvalds -------------------------------------------------------------------------------
25681da177e4SLinus Torvalds */
floatx80_to_int32_round_to_zero(floatx80 a)25691da177e4SLinus Torvalds int32 floatx80_to_int32_round_to_zero( floatx80 a )
25701da177e4SLinus Torvalds {
25711da177e4SLinus Torvalds flag aSign;
25721da177e4SLinus Torvalds int32 aExp, shiftCount;
25731da177e4SLinus Torvalds bits64 aSig, savedASig;
25741da177e4SLinus Torvalds int32 z;
25751da177e4SLinus Torvalds
25761da177e4SLinus Torvalds aSig = extractFloatx80Frac( a );
25771da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
25781da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
25791da177e4SLinus Torvalds shiftCount = 0x403E - aExp;
25801da177e4SLinus Torvalds if ( shiftCount < 32 ) {
25811da177e4SLinus Torvalds if ( ( aExp == 0x7FFF ) && (bits64) ( aSig<<1 ) ) aSign = 0;
25821da177e4SLinus Torvalds goto invalid;
25831da177e4SLinus Torvalds }
25841da177e4SLinus Torvalds else if ( 63 < shiftCount ) {
2585f148af25SRichard Purdie if ( aExp || aSig ) float_raise( float_flag_inexact );
25861da177e4SLinus Torvalds return 0;
25871da177e4SLinus Torvalds }
25881da177e4SLinus Torvalds savedASig = aSig;
25891da177e4SLinus Torvalds aSig >>= shiftCount;
25901da177e4SLinus Torvalds z = aSig;
25911da177e4SLinus Torvalds if ( aSign ) z = - z;
25921da177e4SLinus Torvalds if ( ( z < 0 ) ^ aSign ) {
25931da177e4SLinus Torvalds invalid:
2594f148af25SRichard Purdie float_raise( float_flag_invalid );
25951da177e4SLinus Torvalds return aSign ? 0x80000000 : 0x7FFFFFFF;
25961da177e4SLinus Torvalds }
25971da177e4SLinus Torvalds if ( ( aSig<<shiftCount ) != savedASig ) {
2598f148af25SRichard Purdie float_raise( float_flag_inexact );
25991da177e4SLinus Torvalds }
26001da177e4SLinus Torvalds return z;
26011da177e4SLinus Torvalds
26021da177e4SLinus Torvalds }
26031da177e4SLinus Torvalds
26041da177e4SLinus Torvalds /*
26051da177e4SLinus Torvalds -------------------------------------------------------------------------------
26061da177e4SLinus Torvalds Returns the result of converting the extended double-precision floating-
26071da177e4SLinus Torvalds point value `a' to the single-precision floating-point format. The
26081da177e4SLinus Torvalds conversion is performed according to the IEC/IEEE Standard for Binary
26091da177e4SLinus Torvalds Floating-point Arithmetic.
26101da177e4SLinus Torvalds -------------------------------------------------------------------------------
26111da177e4SLinus Torvalds */
floatx80_to_float32(struct roundingData * roundData,floatx80 a)2612f148af25SRichard Purdie float32 floatx80_to_float32( struct roundingData *roundData, floatx80 a )
26131da177e4SLinus Torvalds {
26141da177e4SLinus Torvalds flag aSign;
26151da177e4SLinus Torvalds int32 aExp;
26161da177e4SLinus Torvalds bits64 aSig;
26171da177e4SLinus Torvalds
26181da177e4SLinus Torvalds aSig = extractFloatx80Frac( a );
26191da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
26201da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
26211da177e4SLinus Torvalds if ( aExp == 0x7FFF ) {
26221da177e4SLinus Torvalds if ( (bits64) ( aSig<<1 ) ) {
26231da177e4SLinus Torvalds return commonNaNToFloat32( floatx80ToCommonNaN( a ) );
26241da177e4SLinus Torvalds }
26251da177e4SLinus Torvalds return packFloat32( aSign, 0xFF, 0 );
26261da177e4SLinus Torvalds }
26271da177e4SLinus Torvalds shift64RightJamming( aSig, 33, &aSig );
26281da177e4SLinus Torvalds if ( aExp || aSig ) aExp -= 0x3F81;
2629f148af25SRichard Purdie return roundAndPackFloat32( roundData, aSign, aExp, aSig );
26301da177e4SLinus Torvalds
26311da177e4SLinus Torvalds }
26321da177e4SLinus Torvalds
26331da177e4SLinus Torvalds /*
26341da177e4SLinus Torvalds -------------------------------------------------------------------------------
26351da177e4SLinus Torvalds Returns the result of converting the extended double-precision floating-
26361da177e4SLinus Torvalds point value `a' to the double-precision floating-point format. The
26371da177e4SLinus Torvalds conversion is performed according to the IEC/IEEE Standard for Binary
26381da177e4SLinus Torvalds Floating-point Arithmetic.
26391da177e4SLinus Torvalds -------------------------------------------------------------------------------
26401da177e4SLinus Torvalds */
floatx80_to_float64(struct roundingData * roundData,floatx80 a)2641f148af25SRichard Purdie float64 floatx80_to_float64( struct roundingData *roundData, floatx80 a )
26421da177e4SLinus Torvalds {
26431da177e4SLinus Torvalds flag aSign;
26441da177e4SLinus Torvalds int32 aExp;
26451da177e4SLinus Torvalds bits64 aSig, zSig;
26461da177e4SLinus Torvalds
26471da177e4SLinus Torvalds aSig = extractFloatx80Frac( a );
26481da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
26491da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
26501da177e4SLinus Torvalds if ( aExp == 0x7FFF ) {
26511da177e4SLinus Torvalds if ( (bits64) ( aSig<<1 ) ) {
26521da177e4SLinus Torvalds return commonNaNToFloat64( floatx80ToCommonNaN( a ) );
26531da177e4SLinus Torvalds }
26541da177e4SLinus Torvalds return packFloat64( aSign, 0x7FF, 0 );
26551da177e4SLinus Torvalds }
26561da177e4SLinus Torvalds shift64RightJamming( aSig, 1, &zSig );
26571da177e4SLinus Torvalds if ( aExp || aSig ) aExp -= 0x3C01;
2658f148af25SRichard Purdie return roundAndPackFloat64( roundData, aSign, aExp, zSig );
26591da177e4SLinus Torvalds
26601da177e4SLinus Torvalds }
26611da177e4SLinus Torvalds
26621da177e4SLinus Torvalds /*
26631da177e4SLinus Torvalds -------------------------------------------------------------------------------
26641da177e4SLinus Torvalds Rounds the extended double-precision floating-point value `a' to an integer,
26651da177e4SLinus Torvalds and returns the result as an extended quadruple-precision floating-point
26661da177e4SLinus Torvalds value. The operation is performed according to the IEC/IEEE Standard for
26671da177e4SLinus Torvalds Binary Floating-point Arithmetic.
26681da177e4SLinus Torvalds -------------------------------------------------------------------------------
26691da177e4SLinus Torvalds */
floatx80_round_to_int(struct roundingData * roundData,floatx80 a)2670f148af25SRichard Purdie floatx80 floatx80_round_to_int( struct roundingData *roundData, floatx80 a )
26711da177e4SLinus Torvalds {
26721da177e4SLinus Torvalds flag aSign;
26731da177e4SLinus Torvalds int32 aExp;
26741da177e4SLinus Torvalds bits64 lastBitMask, roundBitsMask;
26751da177e4SLinus Torvalds int8 roundingMode;
26761da177e4SLinus Torvalds floatx80 z;
26771da177e4SLinus Torvalds
26781da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
26791da177e4SLinus Torvalds if ( 0x403E <= aExp ) {
26801da177e4SLinus Torvalds if ( ( aExp == 0x7FFF ) && (bits64) ( extractFloatx80Frac( a )<<1 ) ) {
26811da177e4SLinus Torvalds return propagateFloatx80NaN( a, a );
26821da177e4SLinus Torvalds }
26831da177e4SLinus Torvalds return a;
26841da177e4SLinus Torvalds }
26851da177e4SLinus Torvalds if ( aExp <= 0x3FFE ) {
26861da177e4SLinus Torvalds if ( ( aExp == 0 )
26871da177e4SLinus Torvalds && ( (bits64) ( extractFloatx80Frac( a )<<1 ) == 0 ) ) {
26881da177e4SLinus Torvalds return a;
26891da177e4SLinus Torvalds }
2690f148af25SRichard Purdie roundData->exception |= float_flag_inexact;
26911da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
2692f148af25SRichard Purdie switch ( roundData->mode ) {
26931da177e4SLinus Torvalds case float_round_nearest_even:
26941da177e4SLinus Torvalds if ( ( aExp == 0x3FFE ) && (bits64) ( extractFloatx80Frac( a )<<1 )
26951da177e4SLinus Torvalds ) {
26961da177e4SLinus Torvalds return
26971da177e4SLinus Torvalds packFloatx80( aSign, 0x3FFF, LIT64( 0x8000000000000000 ) );
26981da177e4SLinus Torvalds }
26991da177e4SLinus Torvalds break;
27001da177e4SLinus Torvalds case float_round_down:
27011da177e4SLinus Torvalds return
27021da177e4SLinus Torvalds aSign ?
27031da177e4SLinus Torvalds packFloatx80( 1, 0x3FFF, LIT64( 0x8000000000000000 ) )
27041da177e4SLinus Torvalds : packFloatx80( 0, 0, 0 );
27051da177e4SLinus Torvalds case float_round_up:
27061da177e4SLinus Torvalds return
27071da177e4SLinus Torvalds aSign ? packFloatx80( 1, 0, 0 )
27081da177e4SLinus Torvalds : packFloatx80( 0, 0x3FFF, LIT64( 0x8000000000000000 ) );
27091da177e4SLinus Torvalds }
27101da177e4SLinus Torvalds return packFloatx80( aSign, 0, 0 );
27111da177e4SLinus Torvalds }
27121da177e4SLinus Torvalds lastBitMask = 1;
27131da177e4SLinus Torvalds lastBitMask <<= 0x403E - aExp;
27141da177e4SLinus Torvalds roundBitsMask = lastBitMask - 1;
27151da177e4SLinus Torvalds z = a;
2716f148af25SRichard Purdie roundingMode = roundData->mode;
27171da177e4SLinus Torvalds if ( roundingMode == float_round_nearest_even ) {
27181da177e4SLinus Torvalds z.low += lastBitMask>>1;
27191da177e4SLinus Torvalds if ( ( z.low & roundBitsMask ) == 0 ) z.low &= ~ lastBitMask;
27201da177e4SLinus Torvalds }
27211da177e4SLinus Torvalds else if ( roundingMode != float_round_to_zero ) {
27221da177e4SLinus Torvalds if ( extractFloatx80Sign( z ) ^ ( roundingMode == float_round_up ) ) {
27231da177e4SLinus Torvalds z.low += roundBitsMask;
27241da177e4SLinus Torvalds }
27251da177e4SLinus Torvalds }
27261da177e4SLinus Torvalds z.low &= ~ roundBitsMask;
27271da177e4SLinus Torvalds if ( z.low == 0 ) {
27281da177e4SLinus Torvalds ++z.high;
27291da177e4SLinus Torvalds z.low = LIT64( 0x8000000000000000 );
27301da177e4SLinus Torvalds }
2731f148af25SRichard Purdie if ( z.low != a.low ) roundData->exception |= float_flag_inexact;
27321da177e4SLinus Torvalds return z;
27331da177e4SLinus Torvalds
27341da177e4SLinus Torvalds }
27351da177e4SLinus Torvalds
27361da177e4SLinus Torvalds /*
27371da177e4SLinus Torvalds -------------------------------------------------------------------------------
27381da177e4SLinus Torvalds Returns the result of adding the absolute values of the extended double-
27391da177e4SLinus Torvalds precision floating-point values `a' and `b'. If `zSign' is true, the sum is
27401da177e4SLinus Torvalds negated before being returned. `zSign' is ignored if the result is a NaN.
27411da177e4SLinus Torvalds The addition is performed according to the IEC/IEEE Standard for Binary
27421da177e4SLinus Torvalds Floating-point Arithmetic.
27431da177e4SLinus Torvalds -------------------------------------------------------------------------------
27441da177e4SLinus Torvalds */
addFloatx80Sigs(struct roundingData * roundData,floatx80 a,floatx80 b,flag zSign)2745f148af25SRichard Purdie static floatx80 addFloatx80Sigs( struct roundingData *roundData, floatx80 a, floatx80 b, flag zSign )
27461da177e4SLinus Torvalds {
27471da177e4SLinus Torvalds int32 aExp, bExp, zExp;
27481da177e4SLinus Torvalds bits64 aSig, bSig, zSig0, zSig1;
27491da177e4SLinus Torvalds int32 expDiff;
27501da177e4SLinus Torvalds
27511da177e4SLinus Torvalds aSig = extractFloatx80Frac( a );
27521da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
27531da177e4SLinus Torvalds bSig = extractFloatx80Frac( b );
27541da177e4SLinus Torvalds bExp = extractFloatx80Exp( b );
27551da177e4SLinus Torvalds expDiff = aExp - bExp;
27561da177e4SLinus Torvalds if ( 0 < expDiff ) {
27571da177e4SLinus Torvalds if ( aExp == 0x7FFF ) {
27581da177e4SLinus Torvalds if ( (bits64) ( aSig<<1 ) ) return propagateFloatx80NaN( a, b );
27591da177e4SLinus Torvalds return a;
27601da177e4SLinus Torvalds }
27611da177e4SLinus Torvalds if ( bExp == 0 ) --expDiff;
27621da177e4SLinus Torvalds shift64ExtraRightJamming( bSig, 0, expDiff, &bSig, &zSig1 );
27631da177e4SLinus Torvalds zExp = aExp;
27641da177e4SLinus Torvalds }
27651da177e4SLinus Torvalds else if ( expDiff < 0 ) {
27661da177e4SLinus Torvalds if ( bExp == 0x7FFF ) {
27671da177e4SLinus Torvalds if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
27681da177e4SLinus Torvalds return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
27691da177e4SLinus Torvalds }
27701da177e4SLinus Torvalds if ( aExp == 0 ) ++expDiff;
27711da177e4SLinus Torvalds shift64ExtraRightJamming( aSig, 0, - expDiff, &aSig, &zSig1 );
27721da177e4SLinus Torvalds zExp = bExp;
27731da177e4SLinus Torvalds }
27741da177e4SLinus Torvalds else {
27751da177e4SLinus Torvalds if ( aExp == 0x7FFF ) {
27761da177e4SLinus Torvalds if ( (bits64) ( ( aSig | bSig )<<1 ) ) {
27771da177e4SLinus Torvalds return propagateFloatx80NaN( a, b );
27781da177e4SLinus Torvalds }
27791da177e4SLinus Torvalds return a;
27801da177e4SLinus Torvalds }
27811da177e4SLinus Torvalds zSig1 = 0;
27821da177e4SLinus Torvalds zSig0 = aSig + bSig;
27831da177e4SLinus Torvalds if ( aExp == 0 ) {
27841da177e4SLinus Torvalds normalizeFloatx80Subnormal( zSig0, &zExp, &zSig0 );
27851da177e4SLinus Torvalds goto roundAndPack;
27861da177e4SLinus Torvalds }
27871da177e4SLinus Torvalds zExp = aExp;
27881da177e4SLinus Torvalds goto shiftRight1;
27891da177e4SLinus Torvalds }
27901da177e4SLinus Torvalds
27911da177e4SLinus Torvalds zSig0 = aSig + bSig;
27921da177e4SLinus Torvalds
27931da177e4SLinus Torvalds if ( (sbits64) zSig0 < 0 ) goto roundAndPack;
27941da177e4SLinus Torvalds shiftRight1:
27951da177e4SLinus Torvalds shift64ExtraRightJamming( zSig0, zSig1, 1, &zSig0, &zSig1 );
27961da177e4SLinus Torvalds zSig0 |= LIT64( 0x8000000000000000 );
27971da177e4SLinus Torvalds ++zExp;
27981da177e4SLinus Torvalds roundAndPack:
27991da177e4SLinus Torvalds return
28001da177e4SLinus Torvalds roundAndPackFloatx80(
2801f148af25SRichard Purdie roundData, zSign, zExp, zSig0, zSig1 );
28021da177e4SLinus Torvalds
28031da177e4SLinus Torvalds }
28041da177e4SLinus Torvalds
28051da177e4SLinus Torvalds /*
28061da177e4SLinus Torvalds -------------------------------------------------------------------------------
28071da177e4SLinus Torvalds Returns the result of subtracting the absolute values of the extended
28081da177e4SLinus Torvalds double-precision floating-point values `a' and `b'. If `zSign' is true,
28091da177e4SLinus Torvalds the difference is negated before being returned. `zSign' is ignored if the
28101da177e4SLinus Torvalds result is a NaN. The subtraction is performed according to the IEC/IEEE
28111da177e4SLinus Torvalds Standard for Binary Floating-point Arithmetic.
28121da177e4SLinus Torvalds -------------------------------------------------------------------------------
28131da177e4SLinus Torvalds */
subFloatx80Sigs(struct roundingData * roundData,floatx80 a,floatx80 b,flag zSign)2814f148af25SRichard Purdie static floatx80 subFloatx80Sigs( struct roundingData *roundData, floatx80 a, floatx80 b, flag zSign )
28151da177e4SLinus Torvalds {
28161da177e4SLinus Torvalds int32 aExp, bExp, zExp;
28171da177e4SLinus Torvalds bits64 aSig, bSig, zSig0, zSig1;
28181da177e4SLinus Torvalds int32 expDiff;
28191da177e4SLinus Torvalds floatx80 z;
28201da177e4SLinus Torvalds
28211da177e4SLinus Torvalds aSig = extractFloatx80Frac( a );
28221da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
28231da177e4SLinus Torvalds bSig = extractFloatx80Frac( b );
28241da177e4SLinus Torvalds bExp = extractFloatx80Exp( b );
28251da177e4SLinus Torvalds expDiff = aExp - bExp;
28261da177e4SLinus Torvalds if ( 0 < expDiff ) goto aExpBigger;
28271da177e4SLinus Torvalds if ( expDiff < 0 ) goto bExpBigger;
28281da177e4SLinus Torvalds if ( aExp == 0x7FFF ) {
28291da177e4SLinus Torvalds if ( (bits64) ( ( aSig | bSig )<<1 ) ) {
28301da177e4SLinus Torvalds return propagateFloatx80NaN( a, b );
28311da177e4SLinus Torvalds }
2832f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
28331da177e4SLinus Torvalds z.low = floatx80_default_nan_low;
28341da177e4SLinus Torvalds z.high = floatx80_default_nan_high;
283506c03cacSLennert Buytenhek z.__padding = 0;
28361da177e4SLinus Torvalds return z;
28371da177e4SLinus Torvalds }
28381da177e4SLinus Torvalds if ( aExp == 0 ) {
28391da177e4SLinus Torvalds aExp = 1;
28401da177e4SLinus Torvalds bExp = 1;
28411da177e4SLinus Torvalds }
28421da177e4SLinus Torvalds zSig1 = 0;
28431da177e4SLinus Torvalds if ( bSig < aSig ) goto aBigger;
28441da177e4SLinus Torvalds if ( aSig < bSig ) goto bBigger;
2845f148af25SRichard Purdie return packFloatx80( roundData->mode == float_round_down, 0, 0 );
28461da177e4SLinus Torvalds bExpBigger:
28471da177e4SLinus Torvalds if ( bExp == 0x7FFF ) {
28481da177e4SLinus Torvalds if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
28491da177e4SLinus Torvalds return packFloatx80( zSign ^ 1, 0x7FFF, LIT64( 0x8000000000000000 ) );
28501da177e4SLinus Torvalds }
28511da177e4SLinus Torvalds if ( aExp == 0 ) ++expDiff;
28521da177e4SLinus Torvalds shift128RightJamming( aSig, 0, - expDiff, &aSig, &zSig1 );
28531da177e4SLinus Torvalds bBigger:
28541da177e4SLinus Torvalds sub128( bSig, 0, aSig, zSig1, &zSig0, &zSig1 );
28551da177e4SLinus Torvalds zExp = bExp;
28561da177e4SLinus Torvalds zSign ^= 1;
28571da177e4SLinus Torvalds goto normalizeRoundAndPack;
28581da177e4SLinus Torvalds aExpBigger:
28591da177e4SLinus Torvalds if ( aExp == 0x7FFF ) {
28601da177e4SLinus Torvalds if ( (bits64) ( aSig<<1 ) ) return propagateFloatx80NaN( a, b );
28611da177e4SLinus Torvalds return a;
28621da177e4SLinus Torvalds }
28631da177e4SLinus Torvalds if ( bExp == 0 ) --expDiff;
28641da177e4SLinus Torvalds shift128RightJamming( bSig, 0, expDiff, &bSig, &zSig1 );
28651da177e4SLinus Torvalds aBigger:
28661da177e4SLinus Torvalds sub128( aSig, 0, bSig, zSig1, &zSig0, &zSig1 );
28671da177e4SLinus Torvalds zExp = aExp;
28681da177e4SLinus Torvalds normalizeRoundAndPack:
28691da177e4SLinus Torvalds return
28701da177e4SLinus Torvalds normalizeRoundAndPackFloatx80(
2871f148af25SRichard Purdie roundData, zSign, zExp, zSig0, zSig1 );
28721da177e4SLinus Torvalds
28731da177e4SLinus Torvalds }
28741da177e4SLinus Torvalds
28751da177e4SLinus Torvalds /*
28761da177e4SLinus Torvalds -------------------------------------------------------------------------------
28771da177e4SLinus Torvalds Returns the result of adding the extended double-precision floating-point
28781da177e4SLinus Torvalds values `a' and `b'. The operation is performed according to the IEC/IEEE
28791da177e4SLinus Torvalds Standard for Binary Floating-point Arithmetic.
28801da177e4SLinus Torvalds -------------------------------------------------------------------------------
28811da177e4SLinus Torvalds */
floatx80_add(struct roundingData * roundData,floatx80 a,floatx80 b)2882f148af25SRichard Purdie floatx80 floatx80_add( struct roundingData *roundData, floatx80 a, floatx80 b )
28831da177e4SLinus Torvalds {
28841da177e4SLinus Torvalds flag aSign, bSign;
28851da177e4SLinus Torvalds
28861da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
28871da177e4SLinus Torvalds bSign = extractFloatx80Sign( b );
28881da177e4SLinus Torvalds if ( aSign == bSign ) {
2889f148af25SRichard Purdie return addFloatx80Sigs( roundData, a, b, aSign );
28901da177e4SLinus Torvalds }
28911da177e4SLinus Torvalds else {
2892f148af25SRichard Purdie return subFloatx80Sigs( roundData, a, b, aSign );
28931da177e4SLinus Torvalds }
28941da177e4SLinus Torvalds
28951da177e4SLinus Torvalds }
28961da177e4SLinus Torvalds
28971da177e4SLinus Torvalds /*
28981da177e4SLinus Torvalds -------------------------------------------------------------------------------
28991da177e4SLinus Torvalds Returns the result of subtracting the extended double-precision floating-
29001da177e4SLinus Torvalds point values `a' and `b'. The operation is performed according to the
29011da177e4SLinus Torvalds IEC/IEEE Standard for Binary Floating-point Arithmetic.
29021da177e4SLinus Torvalds -------------------------------------------------------------------------------
29031da177e4SLinus Torvalds */
floatx80_sub(struct roundingData * roundData,floatx80 a,floatx80 b)2904f148af25SRichard Purdie floatx80 floatx80_sub( struct roundingData *roundData, floatx80 a, floatx80 b )
29051da177e4SLinus Torvalds {
29061da177e4SLinus Torvalds flag aSign, bSign;
29071da177e4SLinus Torvalds
29081da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
29091da177e4SLinus Torvalds bSign = extractFloatx80Sign( b );
29101da177e4SLinus Torvalds if ( aSign == bSign ) {
2911f148af25SRichard Purdie return subFloatx80Sigs( roundData, a, b, aSign );
29121da177e4SLinus Torvalds }
29131da177e4SLinus Torvalds else {
2914f148af25SRichard Purdie return addFloatx80Sigs( roundData, a, b, aSign );
29151da177e4SLinus Torvalds }
29161da177e4SLinus Torvalds
29171da177e4SLinus Torvalds }
29181da177e4SLinus Torvalds
29191da177e4SLinus Torvalds /*
29201da177e4SLinus Torvalds -------------------------------------------------------------------------------
29211da177e4SLinus Torvalds Returns the result of multiplying the extended double-precision floating-
29221da177e4SLinus Torvalds point values `a' and `b'. The operation is performed according to the
29231da177e4SLinus Torvalds IEC/IEEE Standard for Binary Floating-point Arithmetic.
29241da177e4SLinus Torvalds -------------------------------------------------------------------------------
29251da177e4SLinus Torvalds */
floatx80_mul(struct roundingData * roundData,floatx80 a,floatx80 b)2926f148af25SRichard Purdie floatx80 floatx80_mul( struct roundingData *roundData, floatx80 a, floatx80 b )
29271da177e4SLinus Torvalds {
29281da177e4SLinus Torvalds flag aSign, bSign, zSign;
29291da177e4SLinus Torvalds int32 aExp, bExp, zExp;
29301da177e4SLinus Torvalds bits64 aSig, bSig, zSig0, zSig1;
29311da177e4SLinus Torvalds floatx80 z;
29321da177e4SLinus Torvalds
29331da177e4SLinus Torvalds aSig = extractFloatx80Frac( a );
29341da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
29351da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
29361da177e4SLinus Torvalds bSig = extractFloatx80Frac( b );
29371da177e4SLinus Torvalds bExp = extractFloatx80Exp( b );
29381da177e4SLinus Torvalds bSign = extractFloatx80Sign( b );
29391da177e4SLinus Torvalds zSign = aSign ^ bSign;
29401da177e4SLinus Torvalds if ( aExp == 0x7FFF ) {
29411da177e4SLinus Torvalds if ( (bits64) ( aSig<<1 )
29421da177e4SLinus Torvalds || ( ( bExp == 0x7FFF ) && (bits64) ( bSig<<1 ) ) ) {
29431da177e4SLinus Torvalds return propagateFloatx80NaN( a, b );
29441da177e4SLinus Torvalds }
29451da177e4SLinus Torvalds if ( ( bExp | bSig ) == 0 ) goto invalid;
29461da177e4SLinus Torvalds return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
29471da177e4SLinus Torvalds }
29481da177e4SLinus Torvalds if ( bExp == 0x7FFF ) {
29491da177e4SLinus Torvalds if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
29501da177e4SLinus Torvalds if ( ( aExp | aSig ) == 0 ) {
29511da177e4SLinus Torvalds invalid:
2952f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
29531da177e4SLinus Torvalds z.low = floatx80_default_nan_low;
29541da177e4SLinus Torvalds z.high = floatx80_default_nan_high;
295506c03cacSLennert Buytenhek z.__padding = 0;
29561da177e4SLinus Torvalds return z;
29571da177e4SLinus Torvalds }
29581da177e4SLinus Torvalds return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
29591da177e4SLinus Torvalds }
29601da177e4SLinus Torvalds if ( aExp == 0 ) {
29611da177e4SLinus Torvalds if ( aSig == 0 ) return packFloatx80( zSign, 0, 0 );
29621da177e4SLinus Torvalds normalizeFloatx80Subnormal( aSig, &aExp, &aSig );
29631da177e4SLinus Torvalds }
29641da177e4SLinus Torvalds if ( bExp == 0 ) {
29651da177e4SLinus Torvalds if ( bSig == 0 ) return packFloatx80( zSign, 0, 0 );
29661da177e4SLinus Torvalds normalizeFloatx80Subnormal( bSig, &bExp, &bSig );
29671da177e4SLinus Torvalds }
29681da177e4SLinus Torvalds zExp = aExp + bExp - 0x3FFE;
29691da177e4SLinus Torvalds mul64To128( aSig, bSig, &zSig0, &zSig1 );
29701da177e4SLinus Torvalds if ( 0 < (sbits64) zSig0 ) {
29711da177e4SLinus Torvalds shortShift128Left( zSig0, zSig1, 1, &zSig0, &zSig1 );
29721da177e4SLinus Torvalds --zExp;
29731da177e4SLinus Torvalds }
29741da177e4SLinus Torvalds return
29751da177e4SLinus Torvalds roundAndPackFloatx80(
2976f148af25SRichard Purdie roundData, zSign, zExp, zSig0, zSig1 );
29771da177e4SLinus Torvalds
29781da177e4SLinus Torvalds }
29791da177e4SLinus Torvalds
29801da177e4SLinus Torvalds /*
29811da177e4SLinus Torvalds -------------------------------------------------------------------------------
29821da177e4SLinus Torvalds Returns the result of dividing the extended double-precision floating-point
29831da177e4SLinus Torvalds value `a' by the corresponding value `b'. The operation is performed
29841da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
29851da177e4SLinus Torvalds -------------------------------------------------------------------------------
29861da177e4SLinus Torvalds */
floatx80_div(struct roundingData * roundData,floatx80 a,floatx80 b)2987f148af25SRichard Purdie floatx80 floatx80_div( struct roundingData *roundData, floatx80 a, floatx80 b )
29881da177e4SLinus Torvalds {
29891da177e4SLinus Torvalds flag aSign, bSign, zSign;
29901da177e4SLinus Torvalds int32 aExp, bExp, zExp;
29911da177e4SLinus Torvalds bits64 aSig, bSig, zSig0, zSig1;
29921da177e4SLinus Torvalds bits64 rem0, rem1, rem2, term0, term1, term2;
29931da177e4SLinus Torvalds floatx80 z;
29941da177e4SLinus Torvalds
29951da177e4SLinus Torvalds aSig = extractFloatx80Frac( a );
29961da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
29971da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
29981da177e4SLinus Torvalds bSig = extractFloatx80Frac( b );
29991da177e4SLinus Torvalds bExp = extractFloatx80Exp( b );
30001da177e4SLinus Torvalds bSign = extractFloatx80Sign( b );
30011da177e4SLinus Torvalds zSign = aSign ^ bSign;
30021da177e4SLinus Torvalds if ( aExp == 0x7FFF ) {
30031da177e4SLinus Torvalds if ( (bits64) ( aSig<<1 ) ) return propagateFloatx80NaN( a, b );
30041da177e4SLinus Torvalds if ( bExp == 0x7FFF ) {
30051da177e4SLinus Torvalds if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
30061da177e4SLinus Torvalds goto invalid;
30071da177e4SLinus Torvalds }
30081da177e4SLinus Torvalds return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
30091da177e4SLinus Torvalds }
30101da177e4SLinus Torvalds if ( bExp == 0x7FFF ) {
30111da177e4SLinus Torvalds if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
30121da177e4SLinus Torvalds return packFloatx80( zSign, 0, 0 );
30131da177e4SLinus Torvalds }
30141da177e4SLinus Torvalds if ( bExp == 0 ) {
30151da177e4SLinus Torvalds if ( bSig == 0 ) {
30161da177e4SLinus Torvalds if ( ( aExp | aSig ) == 0 ) {
30171da177e4SLinus Torvalds invalid:
3018f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
30191da177e4SLinus Torvalds z.low = floatx80_default_nan_low;
30201da177e4SLinus Torvalds z.high = floatx80_default_nan_high;
302106c03cacSLennert Buytenhek z.__padding = 0;
30221da177e4SLinus Torvalds return z;
30231da177e4SLinus Torvalds }
3024f148af25SRichard Purdie roundData->exception |= float_flag_divbyzero;
30251da177e4SLinus Torvalds return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
30261da177e4SLinus Torvalds }
30271da177e4SLinus Torvalds normalizeFloatx80Subnormal( bSig, &bExp, &bSig );
30281da177e4SLinus Torvalds }
30291da177e4SLinus Torvalds if ( aExp == 0 ) {
30301da177e4SLinus Torvalds if ( aSig == 0 ) return packFloatx80( zSign, 0, 0 );
30311da177e4SLinus Torvalds normalizeFloatx80Subnormal( aSig, &aExp, &aSig );
30321da177e4SLinus Torvalds }
30331da177e4SLinus Torvalds zExp = aExp - bExp + 0x3FFE;
30341da177e4SLinus Torvalds rem1 = 0;
30351da177e4SLinus Torvalds if ( bSig <= aSig ) {
30361da177e4SLinus Torvalds shift128Right( aSig, 0, 1, &aSig, &rem1 );
30371da177e4SLinus Torvalds ++zExp;
30381da177e4SLinus Torvalds }
30391da177e4SLinus Torvalds zSig0 = estimateDiv128To64( aSig, rem1, bSig );
30401da177e4SLinus Torvalds mul64To128( bSig, zSig0, &term0, &term1 );
30411da177e4SLinus Torvalds sub128( aSig, rem1, term0, term1, &rem0, &rem1 );
30421da177e4SLinus Torvalds while ( (sbits64) rem0 < 0 ) {
30431da177e4SLinus Torvalds --zSig0;
30441da177e4SLinus Torvalds add128( rem0, rem1, 0, bSig, &rem0, &rem1 );
30451da177e4SLinus Torvalds }
30461da177e4SLinus Torvalds zSig1 = estimateDiv128To64( rem1, 0, bSig );
30471da177e4SLinus Torvalds if ( (bits64) ( zSig1<<1 ) <= 8 ) {
30481da177e4SLinus Torvalds mul64To128( bSig, zSig1, &term1, &term2 );
30491da177e4SLinus Torvalds sub128( rem1, 0, term1, term2, &rem1, &rem2 );
30501da177e4SLinus Torvalds while ( (sbits64) rem1 < 0 ) {
30511da177e4SLinus Torvalds --zSig1;
30521da177e4SLinus Torvalds add128( rem1, rem2, 0, bSig, &rem1, &rem2 );
30531da177e4SLinus Torvalds }
30541da177e4SLinus Torvalds zSig1 |= ( ( rem1 | rem2 ) != 0 );
30551da177e4SLinus Torvalds }
30561da177e4SLinus Torvalds return
30571da177e4SLinus Torvalds roundAndPackFloatx80(
3058f148af25SRichard Purdie roundData, zSign, zExp, zSig0, zSig1 );
30591da177e4SLinus Torvalds
30601da177e4SLinus Torvalds }
30611da177e4SLinus Torvalds
30621da177e4SLinus Torvalds /*
30631da177e4SLinus Torvalds -------------------------------------------------------------------------------
30641da177e4SLinus Torvalds Returns the remainder of the extended double-precision floating-point value
30651da177e4SLinus Torvalds `a' with respect to the corresponding value `b'. The operation is performed
30661da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
30671da177e4SLinus Torvalds -------------------------------------------------------------------------------
30681da177e4SLinus Torvalds */
floatx80_rem(struct roundingData * roundData,floatx80 a,floatx80 b)3069f148af25SRichard Purdie floatx80 floatx80_rem( struct roundingData *roundData, floatx80 a, floatx80 b )
30701da177e4SLinus Torvalds {
30711da177e4SLinus Torvalds flag aSign, bSign, zSign;
30721da177e4SLinus Torvalds int32 aExp, bExp, expDiff;
30731da177e4SLinus Torvalds bits64 aSig0, aSig1, bSig;
30741da177e4SLinus Torvalds bits64 q, term0, term1, alternateASig0, alternateASig1;
30751da177e4SLinus Torvalds floatx80 z;
30761da177e4SLinus Torvalds
30771da177e4SLinus Torvalds aSig0 = extractFloatx80Frac( a );
30781da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
30791da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
30801da177e4SLinus Torvalds bSig = extractFloatx80Frac( b );
30811da177e4SLinus Torvalds bExp = extractFloatx80Exp( b );
30821da177e4SLinus Torvalds bSign = extractFloatx80Sign( b );
30831da177e4SLinus Torvalds if ( aExp == 0x7FFF ) {
30841da177e4SLinus Torvalds if ( (bits64) ( aSig0<<1 )
30851da177e4SLinus Torvalds || ( ( bExp == 0x7FFF ) && (bits64) ( bSig<<1 ) ) ) {
30861da177e4SLinus Torvalds return propagateFloatx80NaN( a, b );
30871da177e4SLinus Torvalds }
30881da177e4SLinus Torvalds goto invalid;
30891da177e4SLinus Torvalds }
30901da177e4SLinus Torvalds if ( bExp == 0x7FFF ) {
30911da177e4SLinus Torvalds if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b );
30921da177e4SLinus Torvalds return a;
30931da177e4SLinus Torvalds }
30941da177e4SLinus Torvalds if ( bExp == 0 ) {
30951da177e4SLinus Torvalds if ( bSig == 0 ) {
30961da177e4SLinus Torvalds invalid:
3097f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
30981da177e4SLinus Torvalds z.low = floatx80_default_nan_low;
30991da177e4SLinus Torvalds z.high = floatx80_default_nan_high;
310006c03cacSLennert Buytenhek z.__padding = 0;
31011da177e4SLinus Torvalds return z;
31021da177e4SLinus Torvalds }
31031da177e4SLinus Torvalds normalizeFloatx80Subnormal( bSig, &bExp, &bSig );
31041da177e4SLinus Torvalds }
31051da177e4SLinus Torvalds if ( aExp == 0 ) {
31061da177e4SLinus Torvalds if ( (bits64) ( aSig0<<1 ) == 0 ) return a;
31071da177e4SLinus Torvalds normalizeFloatx80Subnormal( aSig0, &aExp, &aSig0 );
31081da177e4SLinus Torvalds }
31091da177e4SLinus Torvalds bSig |= LIT64( 0x8000000000000000 );
31101da177e4SLinus Torvalds zSign = aSign;
31111da177e4SLinus Torvalds expDiff = aExp - bExp;
31121da177e4SLinus Torvalds aSig1 = 0;
31131da177e4SLinus Torvalds if ( expDiff < 0 ) {
31141da177e4SLinus Torvalds if ( expDiff < -1 ) return a;
31151da177e4SLinus Torvalds shift128Right( aSig0, 0, 1, &aSig0, &aSig1 );
31161da177e4SLinus Torvalds expDiff = 0;
31171da177e4SLinus Torvalds }
31181da177e4SLinus Torvalds q = ( bSig <= aSig0 );
31191da177e4SLinus Torvalds if ( q ) aSig0 -= bSig;
31201da177e4SLinus Torvalds expDiff -= 64;
31211da177e4SLinus Torvalds while ( 0 < expDiff ) {
31221da177e4SLinus Torvalds q = estimateDiv128To64( aSig0, aSig1, bSig );
31231da177e4SLinus Torvalds q = ( 2 < q ) ? q - 2 : 0;
31241da177e4SLinus Torvalds mul64To128( bSig, q, &term0, &term1 );
31251da177e4SLinus Torvalds sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 );
31261da177e4SLinus Torvalds shortShift128Left( aSig0, aSig1, 62, &aSig0, &aSig1 );
31271da177e4SLinus Torvalds expDiff -= 62;
31281da177e4SLinus Torvalds }
31291da177e4SLinus Torvalds expDiff += 64;
31301da177e4SLinus Torvalds if ( 0 < expDiff ) {
31311da177e4SLinus Torvalds q = estimateDiv128To64( aSig0, aSig1, bSig );
31321da177e4SLinus Torvalds q = ( 2 < q ) ? q - 2 : 0;
31331da177e4SLinus Torvalds q >>= 64 - expDiff;
31341da177e4SLinus Torvalds mul64To128( bSig, q<<( 64 - expDiff ), &term0, &term1 );
31351da177e4SLinus Torvalds sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 );
31361da177e4SLinus Torvalds shortShift128Left( 0, bSig, 64 - expDiff, &term0, &term1 );
31371da177e4SLinus Torvalds while ( le128( term0, term1, aSig0, aSig1 ) ) {
31381da177e4SLinus Torvalds ++q;
31391da177e4SLinus Torvalds sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 );
31401da177e4SLinus Torvalds }
31411da177e4SLinus Torvalds }
31421da177e4SLinus Torvalds else {
31431da177e4SLinus Torvalds term1 = 0;
31441da177e4SLinus Torvalds term0 = bSig;
31451da177e4SLinus Torvalds }
31461da177e4SLinus Torvalds sub128( term0, term1, aSig0, aSig1, &alternateASig0, &alternateASig1 );
31471da177e4SLinus Torvalds if ( lt128( alternateASig0, alternateASig1, aSig0, aSig1 )
31481da177e4SLinus Torvalds || ( eq128( alternateASig0, alternateASig1, aSig0, aSig1 )
31491da177e4SLinus Torvalds && ( q & 1 ) )
31501da177e4SLinus Torvalds ) {
31511da177e4SLinus Torvalds aSig0 = alternateASig0;
31521da177e4SLinus Torvalds aSig1 = alternateASig1;
31531da177e4SLinus Torvalds zSign = ! zSign;
31541da177e4SLinus Torvalds }
3155f148af25SRichard Purdie
31561da177e4SLinus Torvalds return
31571da177e4SLinus Torvalds normalizeRoundAndPackFloatx80(
3158f148af25SRichard Purdie roundData, zSign, bExp + expDiff, aSig0, aSig1 );
31591da177e4SLinus Torvalds
31601da177e4SLinus Torvalds }
31611da177e4SLinus Torvalds
31621da177e4SLinus Torvalds /*
31631da177e4SLinus Torvalds -------------------------------------------------------------------------------
31641da177e4SLinus Torvalds Returns the square root of the extended double-precision floating-point
31651da177e4SLinus Torvalds value `a'. The operation is performed according to the IEC/IEEE Standard
31661da177e4SLinus Torvalds for Binary Floating-point Arithmetic.
31671da177e4SLinus Torvalds -------------------------------------------------------------------------------
31681da177e4SLinus Torvalds */
floatx80_sqrt(struct roundingData * roundData,floatx80 a)3169f148af25SRichard Purdie floatx80 floatx80_sqrt( struct roundingData *roundData, floatx80 a )
31701da177e4SLinus Torvalds {
31711da177e4SLinus Torvalds flag aSign;
31721da177e4SLinus Torvalds int32 aExp, zExp;
31731da177e4SLinus Torvalds bits64 aSig0, aSig1, zSig0, zSig1;
31741da177e4SLinus Torvalds bits64 rem0, rem1, rem2, rem3, term0, term1, term2, term3;
31751da177e4SLinus Torvalds bits64 shiftedRem0, shiftedRem1;
31761da177e4SLinus Torvalds floatx80 z;
31771da177e4SLinus Torvalds
31781da177e4SLinus Torvalds aSig0 = extractFloatx80Frac( a );
31791da177e4SLinus Torvalds aExp = extractFloatx80Exp( a );
31801da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
31811da177e4SLinus Torvalds if ( aExp == 0x7FFF ) {
31821da177e4SLinus Torvalds if ( (bits64) ( aSig0<<1 ) ) return propagateFloatx80NaN( a, a );
31831da177e4SLinus Torvalds if ( ! aSign ) return a;
31841da177e4SLinus Torvalds goto invalid;
31851da177e4SLinus Torvalds }
31861da177e4SLinus Torvalds if ( aSign ) {
31871da177e4SLinus Torvalds if ( ( aExp | aSig0 ) == 0 ) return a;
31881da177e4SLinus Torvalds invalid:
3189f148af25SRichard Purdie roundData->exception |= float_flag_invalid;
31901da177e4SLinus Torvalds z.low = floatx80_default_nan_low;
31911da177e4SLinus Torvalds z.high = floatx80_default_nan_high;
319206c03cacSLennert Buytenhek z.__padding = 0;
31931da177e4SLinus Torvalds return z;
31941da177e4SLinus Torvalds }
31951da177e4SLinus Torvalds if ( aExp == 0 ) {
31961da177e4SLinus Torvalds if ( aSig0 == 0 ) return packFloatx80( 0, 0, 0 );
31971da177e4SLinus Torvalds normalizeFloatx80Subnormal( aSig0, &aExp, &aSig0 );
31981da177e4SLinus Torvalds }
31991da177e4SLinus Torvalds zExp = ( ( aExp - 0x3FFF )>>1 ) + 0x3FFF;
32001da177e4SLinus Torvalds zSig0 = estimateSqrt32( aExp, aSig0>>32 );
32011da177e4SLinus Torvalds zSig0 <<= 31;
32021da177e4SLinus Torvalds aSig1 = 0;
32031da177e4SLinus Torvalds shift128Right( aSig0, 0, ( aExp & 1 ) + 2, &aSig0, &aSig1 );
32041da177e4SLinus Torvalds zSig0 = estimateDiv128To64( aSig0, aSig1, zSig0 ) + zSig0 + 4;
32051da177e4SLinus Torvalds if ( 0 <= (sbits64) zSig0 ) zSig0 = LIT64( 0xFFFFFFFFFFFFFFFF );
32061da177e4SLinus Torvalds shortShift128Left( aSig0, aSig1, 2, &aSig0, &aSig1 );
32071da177e4SLinus Torvalds mul64To128( zSig0, zSig0, &term0, &term1 );
32081da177e4SLinus Torvalds sub128( aSig0, aSig1, term0, term1, &rem0, &rem1 );
32091da177e4SLinus Torvalds while ( (sbits64) rem0 < 0 ) {
32101da177e4SLinus Torvalds --zSig0;
32111da177e4SLinus Torvalds shortShift128Left( 0, zSig0, 1, &term0, &term1 );
32121da177e4SLinus Torvalds term1 |= 1;
32131da177e4SLinus Torvalds add128( rem0, rem1, term0, term1, &rem0, &rem1 );
32141da177e4SLinus Torvalds }
32151da177e4SLinus Torvalds shortShift128Left( rem0, rem1, 63, &shiftedRem0, &shiftedRem1 );
32161da177e4SLinus Torvalds zSig1 = estimateDiv128To64( shiftedRem0, shiftedRem1, zSig0 );
32171da177e4SLinus Torvalds if ( (bits64) ( zSig1<<1 ) <= 10 ) {
32181da177e4SLinus Torvalds if ( zSig1 == 0 ) zSig1 = 1;
32191da177e4SLinus Torvalds mul64To128( zSig0, zSig1, &term1, &term2 );
32201da177e4SLinus Torvalds shortShift128Left( term1, term2, 1, &term1, &term2 );
32211da177e4SLinus Torvalds sub128( rem1, 0, term1, term2, &rem1, &rem2 );
32221da177e4SLinus Torvalds mul64To128( zSig1, zSig1, &term2, &term3 );
32231da177e4SLinus Torvalds sub192( rem1, rem2, 0, 0, term2, term3, &rem1, &rem2, &rem3 );
32241da177e4SLinus Torvalds while ( (sbits64) rem1 < 0 ) {
32251da177e4SLinus Torvalds --zSig1;
32261da177e4SLinus Torvalds shortShift192Left( 0, zSig0, zSig1, 1, &term1, &term2, &term3 );
32271da177e4SLinus Torvalds term3 |= 1;
32281da177e4SLinus Torvalds add192(
32291da177e4SLinus Torvalds rem1, rem2, rem3, term1, term2, term3, &rem1, &rem2, &rem3 );
32301da177e4SLinus Torvalds }
32311da177e4SLinus Torvalds zSig1 |= ( ( rem1 | rem2 | rem3 ) != 0 );
32321da177e4SLinus Torvalds }
32331da177e4SLinus Torvalds return
32341da177e4SLinus Torvalds roundAndPackFloatx80(
3235f148af25SRichard Purdie roundData, 0, zExp, zSig0, zSig1 );
32361da177e4SLinus Torvalds
32371da177e4SLinus Torvalds }
32381da177e4SLinus Torvalds
32391da177e4SLinus Torvalds /*
32401da177e4SLinus Torvalds -------------------------------------------------------------------------------
32411da177e4SLinus Torvalds Returns 1 if the extended double-precision floating-point value `a' is
32421da177e4SLinus Torvalds equal to the corresponding value `b', and 0 otherwise. The comparison is
32431da177e4SLinus Torvalds performed according to the IEC/IEEE Standard for Binary Floating-point
32441da177e4SLinus Torvalds Arithmetic.
32451da177e4SLinus Torvalds -------------------------------------------------------------------------------
32461da177e4SLinus Torvalds */
floatx80_eq(floatx80 a,floatx80 b)32471da177e4SLinus Torvalds flag floatx80_eq( floatx80 a, floatx80 b )
32481da177e4SLinus Torvalds {
32491da177e4SLinus Torvalds
32501da177e4SLinus Torvalds if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
32511da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( a )<<1 ) )
32521da177e4SLinus Torvalds || ( ( extractFloatx80Exp( b ) == 0x7FFF )
32531da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( b )<<1 ) )
32541da177e4SLinus Torvalds ) {
32551da177e4SLinus Torvalds if ( floatx80_is_signaling_nan( a )
32561da177e4SLinus Torvalds || floatx80_is_signaling_nan( b ) ) {
325754738e82SRichard Purdie float_raise( float_flag_invalid );
32581da177e4SLinus Torvalds }
32591da177e4SLinus Torvalds return 0;
32601da177e4SLinus Torvalds }
32611da177e4SLinus Torvalds return
32621da177e4SLinus Torvalds ( a.low == b.low )
32631da177e4SLinus Torvalds && ( ( a.high == b.high )
32641da177e4SLinus Torvalds || ( ( a.low == 0 )
32651da177e4SLinus Torvalds && ( (bits16) ( ( a.high | b.high )<<1 ) == 0 ) )
32661da177e4SLinus Torvalds );
32671da177e4SLinus Torvalds
32681da177e4SLinus Torvalds }
32691da177e4SLinus Torvalds
32701da177e4SLinus Torvalds /*
32711da177e4SLinus Torvalds -------------------------------------------------------------------------------
32721da177e4SLinus Torvalds Returns 1 if the extended double-precision floating-point value `a' is
32731da177e4SLinus Torvalds less than or equal to the corresponding value `b', and 0 otherwise. The
32741da177e4SLinus Torvalds comparison is performed according to the IEC/IEEE Standard for Binary
32751da177e4SLinus Torvalds Floating-point Arithmetic.
32761da177e4SLinus Torvalds -------------------------------------------------------------------------------
32771da177e4SLinus Torvalds */
floatx80_le(floatx80 a,floatx80 b)32781da177e4SLinus Torvalds flag floatx80_le( floatx80 a, floatx80 b )
32791da177e4SLinus Torvalds {
32801da177e4SLinus Torvalds flag aSign, bSign;
32811da177e4SLinus Torvalds
32821da177e4SLinus Torvalds if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
32831da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( a )<<1 ) )
32841da177e4SLinus Torvalds || ( ( extractFloatx80Exp( b ) == 0x7FFF )
32851da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( b )<<1 ) )
32861da177e4SLinus Torvalds ) {
328754738e82SRichard Purdie float_raise( float_flag_invalid );
32881da177e4SLinus Torvalds return 0;
32891da177e4SLinus Torvalds }
32901da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
32911da177e4SLinus Torvalds bSign = extractFloatx80Sign( b );
32921da177e4SLinus Torvalds if ( aSign != bSign ) {
32931da177e4SLinus Torvalds return
32941da177e4SLinus Torvalds aSign
32951da177e4SLinus Torvalds || ( ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
32961da177e4SLinus Torvalds == 0 );
32971da177e4SLinus Torvalds }
32981da177e4SLinus Torvalds return
32991da177e4SLinus Torvalds aSign ? le128( b.high, b.low, a.high, a.low )
33001da177e4SLinus Torvalds : le128( a.high, a.low, b.high, b.low );
33011da177e4SLinus Torvalds
33021da177e4SLinus Torvalds }
33031da177e4SLinus Torvalds
33041da177e4SLinus Torvalds /*
33051da177e4SLinus Torvalds -------------------------------------------------------------------------------
33061da177e4SLinus Torvalds Returns 1 if the extended double-precision floating-point value `a' is
33071da177e4SLinus Torvalds less than the corresponding value `b', and 0 otherwise. The comparison
33081da177e4SLinus Torvalds is performed according to the IEC/IEEE Standard for Binary Floating-point
33091da177e4SLinus Torvalds Arithmetic.
33101da177e4SLinus Torvalds -------------------------------------------------------------------------------
33111da177e4SLinus Torvalds */
floatx80_lt(floatx80 a,floatx80 b)33121da177e4SLinus Torvalds flag floatx80_lt( floatx80 a, floatx80 b )
33131da177e4SLinus Torvalds {
33141da177e4SLinus Torvalds flag aSign, bSign;
33151da177e4SLinus Torvalds
33161da177e4SLinus Torvalds if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
33171da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( a )<<1 ) )
33181da177e4SLinus Torvalds || ( ( extractFloatx80Exp( b ) == 0x7FFF )
33191da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( b )<<1 ) )
33201da177e4SLinus Torvalds ) {
332154738e82SRichard Purdie float_raise( float_flag_invalid );
33221da177e4SLinus Torvalds return 0;
33231da177e4SLinus Torvalds }
33241da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
33251da177e4SLinus Torvalds bSign = extractFloatx80Sign( b );
33261da177e4SLinus Torvalds if ( aSign != bSign ) {
33271da177e4SLinus Torvalds return
33281da177e4SLinus Torvalds aSign
33291da177e4SLinus Torvalds && ( ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
33301da177e4SLinus Torvalds != 0 );
33311da177e4SLinus Torvalds }
33321da177e4SLinus Torvalds return
33331da177e4SLinus Torvalds aSign ? lt128( b.high, b.low, a.high, a.low )
33341da177e4SLinus Torvalds : lt128( a.high, a.low, b.high, b.low );
33351da177e4SLinus Torvalds
33361da177e4SLinus Torvalds }
33371da177e4SLinus Torvalds
33381da177e4SLinus Torvalds /*
33391da177e4SLinus Torvalds -------------------------------------------------------------------------------
33401da177e4SLinus Torvalds Returns 1 if the extended double-precision floating-point value `a' is equal
33411da177e4SLinus Torvalds to the corresponding value `b', and 0 otherwise. The invalid exception is
33421da177e4SLinus Torvalds raised if either operand is a NaN. Otherwise, the comparison is performed
33431da177e4SLinus Torvalds according to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
33441da177e4SLinus Torvalds -------------------------------------------------------------------------------
33451da177e4SLinus Torvalds */
floatx80_eq_signaling(floatx80 a,floatx80 b)33461da177e4SLinus Torvalds flag floatx80_eq_signaling( floatx80 a, floatx80 b )
33471da177e4SLinus Torvalds {
33481da177e4SLinus Torvalds
33491da177e4SLinus Torvalds if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
33501da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( a )<<1 ) )
33511da177e4SLinus Torvalds || ( ( extractFloatx80Exp( b ) == 0x7FFF )
33521da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( b )<<1 ) )
33531da177e4SLinus Torvalds ) {
335454738e82SRichard Purdie float_raise( float_flag_invalid );
33551da177e4SLinus Torvalds return 0;
33561da177e4SLinus Torvalds }
33571da177e4SLinus Torvalds return
33581da177e4SLinus Torvalds ( a.low == b.low )
33591da177e4SLinus Torvalds && ( ( a.high == b.high )
33601da177e4SLinus Torvalds || ( ( a.low == 0 )
33611da177e4SLinus Torvalds && ( (bits16) ( ( a.high | b.high )<<1 ) == 0 ) )
33621da177e4SLinus Torvalds );
33631da177e4SLinus Torvalds
33641da177e4SLinus Torvalds }
33651da177e4SLinus Torvalds
33661da177e4SLinus Torvalds /*
33671da177e4SLinus Torvalds -------------------------------------------------------------------------------
33681da177e4SLinus Torvalds Returns 1 if the extended double-precision floating-point value `a' is less
33691da177e4SLinus Torvalds than or equal to the corresponding value `b', and 0 otherwise. Quiet NaNs
33701da177e4SLinus Torvalds do not cause an exception. Otherwise, the comparison is performed according
33711da177e4SLinus Torvalds to the IEC/IEEE Standard for Binary Floating-point Arithmetic.
33721da177e4SLinus Torvalds -------------------------------------------------------------------------------
33731da177e4SLinus Torvalds */
floatx80_le_quiet(floatx80 a,floatx80 b)33741da177e4SLinus Torvalds flag floatx80_le_quiet( floatx80 a, floatx80 b )
33751da177e4SLinus Torvalds {
33761da177e4SLinus Torvalds flag aSign, bSign;
33771da177e4SLinus Torvalds
33781da177e4SLinus Torvalds if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
33791da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( a )<<1 ) )
33801da177e4SLinus Torvalds || ( ( extractFloatx80Exp( b ) == 0x7FFF )
33811da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( b )<<1 ) )
33821da177e4SLinus Torvalds ) {
338354738e82SRichard Purdie /* Do nothing, even if NaN as we're quiet */
33841da177e4SLinus Torvalds return 0;
33851da177e4SLinus Torvalds }
33861da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
33871da177e4SLinus Torvalds bSign = extractFloatx80Sign( b );
33881da177e4SLinus Torvalds if ( aSign != bSign ) {
33891da177e4SLinus Torvalds return
33901da177e4SLinus Torvalds aSign
33911da177e4SLinus Torvalds || ( ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
33921da177e4SLinus Torvalds == 0 );
33931da177e4SLinus Torvalds }
33941da177e4SLinus Torvalds return
33951da177e4SLinus Torvalds aSign ? le128( b.high, b.low, a.high, a.low )
33961da177e4SLinus Torvalds : le128( a.high, a.low, b.high, b.low );
33971da177e4SLinus Torvalds
33981da177e4SLinus Torvalds }
33991da177e4SLinus Torvalds
34001da177e4SLinus Torvalds /*
34011da177e4SLinus Torvalds -------------------------------------------------------------------------------
34021da177e4SLinus Torvalds Returns 1 if the extended double-precision floating-point value `a' is less
34031da177e4SLinus Torvalds than the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause
34041da177e4SLinus Torvalds an exception. Otherwise, the comparison is performed according to the
34051da177e4SLinus Torvalds IEC/IEEE Standard for Binary Floating-point Arithmetic.
34061da177e4SLinus Torvalds -------------------------------------------------------------------------------
34071da177e4SLinus Torvalds */
floatx80_lt_quiet(floatx80 a,floatx80 b)34081da177e4SLinus Torvalds flag floatx80_lt_quiet( floatx80 a, floatx80 b )
34091da177e4SLinus Torvalds {
34101da177e4SLinus Torvalds flag aSign, bSign;
34111da177e4SLinus Torvalds
34121da177e4SLinus Torvalds if ( ( ( extractFloatx80Exp( a ) == 0x7FFF )
34131da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( a )<<1 ) )
34141da177e4SLinus Torvalds || ( ( extractFloatx80Exp( b ) == 0x7FFF )
34151da177e4SLinus Torvalds && (bits64) ( extractFloatx80Frac( b )<<1 ) )
34161da177e4SLinus Torvalds ) {
341754738e82SRichard Purdie /* Do nothing, even if NaN as we're quiet */
34181da177e4SLinus Torvalds return 0;
34191da177e4SLinus Torvalds }
34201da177e4SLinus Torvalds aSign = extractFloatx80Sign( a );
34211da177e4SLinus Torvalds bSign = extractFloatx80Sign( b );
34221da177e4SLinus Torvalds if ( aSign != bSign ) {
34231da177e4SLinus Torvalds return
34241da177e4SLinus Torvalds aSign
34251da177e4SLinus Torvalds && ( ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low )
34261da177e4SLinus Torvalds != 0 );
34271da177e4SLinus Torvalds }
34281da177e4SLinus Torvalds return
34291da177e4SLinus Torvalds aSign ? lt128( b.high, b.low, a.high, a.low )
34301da177e4SLinus Torvalds : lt128( a.high, a.low, b.high, b.low );
34311da177e4SLinus Torvalds
34321da177e4SLinus Torvalds }
34331da177e4SLinus Torvalds
34341da177e4SLinus Torvalds #endif
34351da177e4SLinus Torvalds
3436