1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 NetWinder Floating Point Emulator 4 (c) Rebel.COM, 1998,1999 5 (c) Philip Blundell, 2001 6 7 Direct questions, comments to Scott Bambrough <scottb@netwinder.org> 8 9 */ 10 11 #include "fpa11.h" 12 #include "fpopcode.h" 13 14 unsigned int SingleCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd); 15 unsigned int DoubleCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd); 16 unsigned int ExtendedCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd); 17 18 unsigned int EmulateCPDO(const unsigned int opcode) 19 { 20 FPA11 *fpa11 = GET_FPA11(); 21 FPREG *rFd; 22 unsigned int nType, nDest, nRc; 23 struct roundingData roundData; 24 25 /* Get the destination size. If not valid let Linux perform 26 an invalid instruction trap. */ 27 nDest = getDestinationSize(opcode); 28 if (typeNone == nDest) 29 return 0; 30 31 roundData.mode = SetRoundingMode(opcode); 32 roundData.precision = SetRoundingPrecision(opcode); 33 roundData.exception = 0; 34 35 /* Compare the size of the operands in Fn and Fm. 36 Choose the largest size and perform operations in that size, 37 in order to make use of all the precision of the operands. 38 If Fm is a constant, we just grab a constant of a size 39 matching the size of the operand in Fn. */ 40 if (MONADIC_INSTRUCTION(opcode)) 41 nType = nDest; 42 else 43 nType = fpa11->fType[getFn(opcode)]; 44 45 if (!CONSTANT_FM(opcode)) { 46 register unsigned int Fm = getFm(opcode); 47 if (nType < fpa11->fType[Fm]) { 48 nType = fpa11->fType[Fm]; 49 } 50 } 51 52 rFd = &fpa11->fpreg[getFd(opcode)]; 53 54 switch (nType) { 55 case typeSingle: 56 nRc = SingleCPDO(&roundData, opcode, rFd); 57 break; 58 case typeDouble: 59 nRc = DoubleCPDO(&roundData, opcode, rFd); 60 break; 61 #ifdef CONFIG_FPE_NWFPE_XP 62 case typeExtended: 63 nRc = ExtendedCPDO(&roundData, opcode, rFd); 64 break; 65 #endif 66 default: 67 nRc = 0; 68 } 69 70 /* The CPDO functions used to always set the destination type 71 to be the same as their working size. */ 72 73 if (nRc != 0) { 74 /* If the operation succeeded, check to see if the result in the 75 destination register is the correct size. If not force it 76 to be. */ 77 78 fpa11->fType[getFd(opcode)] = nDest; 79 80 #ifdef CONFIG_FPE_NWFPE_XP 81 if (nDest != nType) { 82 switch (nDest) { 83 case typeSingle: 84 { 85 if (typeDouble == nType) 86 rFd->fSingle = float64_to_float32(&roundData, rFd->fDouble); 87 else 88 rFd->fSingle = floatx80_to_float32(&roundData, rFd->fExtended); 89 } 90 break; 91 92 case typeDouble: 93 { 94 if (typeSingle == nType) 95 rFd->fDouble = float32_to_float64(rFd->fSingle); 96 else 97 rFd->fDouble = floatx80_to_float64(&roundData, rFd->fExtended); 98 } 99 break; 100 101 case typeExtended: 102 { 103 if (typeSingle == nType) 104 rFd->fExtended = float32_to_floatx80(rFd->fSingle); 105 else 106 rFd->fExtended = float64_to_floatx80(rFd->fDouble); 107 } 108 break; 109 } 110 } 111 #else 112 if (nDest != nType) { 113 if (nDest == typeSingle) 114 rFd->fSingle = float64_to_float32(&roundData, rFd->fDouble); 115 else 116 rFd->fDouble = float32_to_float64(rFd->fSingle); 117 } 118 #endif 119 } 120 121 if (roundData.exception) 122 float_raise(roundData.exception); 123 124 return nRc; 125 } 126