/* * ARM VFP floating-point operations * * Copyright (c) 2003 Fabrice Bellard * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, see . */ #include "qemu/osdep.h" #include "cpu.h" #include "exec/helper-proto.h" #include "internals.h" #ifdef CONFIG_TCG #include "qemu/log.h" #include "fpu/softfloat.h" #endif /* VFP support. We follow the convention used for VFP instructions: Single precision routines have a "s" suffix, double precision a "d" suffix. */ #ifdef CONFIG_TCG /* Convert host exception flags to vfp form. */ static inline int vfp_exceptbits_from_host(int host_bits) { int target_bits = 0; if (host_bits & float_flag_invalid) { target_bits |= 1; } if (host_bits & float_flag_divbyzero) { target_bits |= 2; } if (host_bits & float_flag_overflow) { target_bits |= 4; } if (host_bits & (float_flag_underflow | float_flag_output_denormal)) { target_bits |= 8; } if (host_bits & float_flag_inexact) { target_bits |= 0x10; } if (host_bits & float_flag_input_denormal) { target_bits |= 0x80; } return target_bits; } /* Convert vfp exception flags to target form. */ static inline int vfp_exceptbits_to_host(int target_bits) { int host_bits = 0; if (target_bits & 1) { host_bits |= float_flag_invalid; } if (target_bits & 2) { host_bits |= float_flag_divbyzero; } if (target_bits & 4) { host_bits |= float_flag_overflow; } if (target_bits & 8) { host_bits |= float_flag_underflow; } if (target_bits & 0x10) { host_bits |= float_flag_inexact; } if (target_bits & 0x80) { host_bits |= float_flag_input_denormal; } return host_bits; } static uint32_t vfp_get_fpscr_from_host(CPUARMState *env) { uint32_t i; i = get_float_exception_flags(&env->vfp.fp_status); i |= get_float_exception_flags(&env->vfp.standard_fp_status); /* FZ16 does not generate an input denormal exception. */ i |= (get_float_exception_flags(&env->vfp.fp_status_f16) & ~float_flag_input_denormal); i |= (get_float_exception_flags(&env->vfp.standard_fp_status_f16) & ~float_flag_input_denormal); return vfp_exceptbits_from_host(i); } static void vfp_set_fpscr_to_host(CPUARMState *env, uint32_t val) { int i; uint32_t changed = env->vfp.xregs[ARM_VFP_FPSCR]; changed ^= val; if (changed & (3 << 22)) { i = (val >> 22) & 3; switch (i) { case FPROUNDING_TIEEVEN: i = float_round_nearest_even; break; case FPROUNDING_POSINF: i = float_round_up; break; case FPROUNDING_NEGINF: i = float_round_down; break; case FPROUNDING_ZERO: i = float_round_to_zero; break; } set_float_rounding_mode(i, &env->vfp.fp_status); set_float_rounding_mode(i, &env->vfp.fp_status_f16); } if (changed & FPCR_FZ16) { bool ftz_enabled = val & FPCR_FZ16; set_flush_to_zero(ftz_enabled, &env->vfp.fp_status_f16); set_flush_to_zero(ftz_enabled, &env->vfp.standard_fp_status_f16); set_flush_inputs_to_zero(ftz_enabled, &env->vfp.fp_status_f16); set_flush_inputs_to_zero(ftz_enabled, &env->vfp.standard_fp_status_f16); } if (changed & FPCR_FZ) { bool ftz_enabled = val & FPCR_FZ; set_flush_to_zero(ftz_enabled, &env->vfp.fp_status); set_flush_inputs_to_zero(ftz_enabled, &env->vfp.fp_status); } if (changed & FPCR_DN) { bool dnan_enabled = val & FPCR_DN; set_default_nan_mode(dnan_enabled, &env->vfp.fp_status); set_default_nan_mode(dnan_enabled, &env->vfp.fp_status_f16); } /* * The exception flags are ORed together when we read fpscr so we * only need to preserve the current state in one of our * float_status values. */ i = vfp_exceptbits_to_host(val); set_float_exception_flags(i, &env->vfp.fp_status); set_float_exception_flags(0, &env->vfp.fp_status_f16); set_float_exception_flags(0, &env->vfp.standard_fp_status); set_float_exception_flags(0, &env->vfp.standard_fp_status_f16); } #else static uint32_t vfp_get_fpscr_from_host(CPUARMState *env) { return 0; } static void vfp_set_fpscr_to_host(CPUARMState *env, uint32_t val) { } #endif uint32_t HELPER(vfp_get_fpscr)(CPUARMState *env) { uint32_t i, fpscr; fpscr = env->vfp.xregs[ARM_VFP_FPSCR] | (env->vfp.vec_len << 16) | (env->vfp.vec_stride << 20); /* * M-profile LTPSIZE overlaps A-profile Stride; whichever of the * two is not applicable to this CPU will always be zero. */ fpscr |= env->v7m.ltpsize << 16; fpscr |= vfp_get_fpscr_from_host(env); i = env->vfp.qc[0] | env->vfp.qc[1] | env->vfp.qc[2] | env->vfp.qc[3]; fpscr |= i ? FPCR_QC : 0; return fpscr; } uint32_t vfp_get_fpscr(CPUARMState *env) { return HELPER(vfp_get_fpscr)(env); } void HELPER(vfp_set_fpscr)(CPUARMState *env, uint32_t val) { ARMCPU *cpu = env_archcpu(env); /* When ARMv8.2-FP16 is not supported, FZ16 is RES0. */ if (!cpu_isar_feature(any_fp16, cpu)) { val &= ~FPCR_FZ16; } vfp_set_fpscr_to_host(env, val); if (!arm_feature(env, ARM_FEATURE_M)) { /* * Short-vector length and stride; on M-profile these bits * are used for different purposes. * We can't make this conditional be "if MVFR0.FPShVec != 0", * because in v7A no-short-vector-support cores still had to * allow Stride/Len to be written with the only effect that * some insns are required to UNDEF if the guest sets them. */ env->vfp.vec_len = extract32(val, 16, 3); env->vfp.vec_stride = extract32(val, 20, 2); } else if (cpu_isar_feature(aa32_mve, cpu)) { env->v7m.ltpsize = extract32(val, FPCR_LTPSIZE_SHIFT, FPCR_LTPSIZE_LENGTH); } if (arm_feature(env, ARM_FEATURE_NEON)) { /* * The bit we set within fpscr_q is arbitrary; the register as a * whole being zero/non-zero is what counts. * TODO: M-profile MVE also has a QC bit. */ env->vfp.qc[0] = val & FPCR_QC; env->vfp.qc[1] = 0; env->vfp.qc[2] = 0; env->vfp.qc[3] = 0; } /* * We don't implement trapped exception handling, so the * trap enable bits, IDE|IXE|UFE|OFE|DZE|IOE are all RAZ/WI (not RES0!) * * The exception flags IOC|DZC|OFC|UFC|IXC|IDC are stored in * fp_status; QC, Len and Stride are stored separately earlier. * Clear out all of those and the RES0 bits: only NZCV, AHP, DN, * FZ, RMode and FZ16 are kept in vfp.xregs[FPSCR]. */ env->vfp.xregs[ARM_VFP_FPSCR] = val & 0xf7c80000; } void vfp_set_fpscr(CPUARMState *env, uint32_t val) { HELPER(vfp_set_fpscr)(env, val); } #ifdef CONFIG_TCG #define VFP_HELPER(name, p) HELPER(glue(glue(vfp_,name),p)) #define VFP_BINOP(name) \ dh_ctype_f16 VFP_HELPER(name, h)(dh_ctype_f16 a, dh_ctype_f16 b, void *fpstp) \ { \ float_status *fpst = fpstp; \ return float16_ ## name(a, b, fpst); \ } \ float32 VFP_HELPER(name, s)(float32 a, float32 b, void *fpstp) \ { \ float_status *fpst = fpstp; \ return float32_ ## name(a, b, fpst); \ } \ float64 VFP_HELPER(name, d)(float64 a, float64 b, void *fpstp) \ { \ float_status *fpst = fpstp; \ return float64_ ## name(a, b, fpst); \ } VFP_BINOP(add) VFP_BINOP(sub) VFP_BINOP(mul) VFP_BINOP(div) VFP_BINOP(min) VFP_BINOP(max) VFP_BINOP(minnum) VFP_BINOP(maxnum) #undef VFP_BINOP dh_ctype_f16 VFP_HELPER(neg, h)(dh_ctype_f16 a) { return float16_chs(a); } float32 VFP_HELPER(neg, s)(float32 a) { return float32_chs(a); } float64 VFP_HELPER(neg, d)(float64 a) { return float64_chs(a); } dh_ctype_f16 VFP_HELPER(abs, h)(dh_ctype_f16 a) { return float16_abs(a); } float32 VFP_HELPER(abs, s)(float32 a) { return float32_abs(a); } float64 VFP_HELPER(abs, d)(float64 a) { return float64_abs(a); } dh_ctype_f16 VFP_HELPER(sqrt, h)(dh_ctype_f16 a, CPUARMState *env) { return float16_sqrt(a, &env->vfp.fp_status_f16); } float32 VFP_HELPER(sqrt, s)(float32 a, CPUARMState *env) { return float32_sqrt(a, &env->vfp.fp_status); } float64 VFP_HELPER(sqrt, d)(float64 a, CPUARMState *env) { return float64_sqrt(a, &env->vfp.fp_status); } static void softfloat_to_vfp_compare(CPUARMState *env, FloatRelation cmp) { uint32_t flags; switch (cmp) { case float_relation_equal: flags = 0x6; break; case float_relation_less: flags = 0x8; break; case float_relation_greater: flags = 0x2; break; case float_relation_unordered: flags = 0x3; break; default: g_assert_not_reached(); } env->vfp.xregs[ARM_VFP_FPSCR] = deposit32(env->vfp.xregs[ARM_VFP_FPSCR], 28, 4, flags); } /* XXX: check quiet/signaling case */ #define DO_VFP_cmp(P, FLOATTYPE, ARGTYPE, FPST) \ void VFP_HELPER(cmp, P)(ARGTYPE a, ARGTYPE b, CPUARMState *env) \ { \ softfloat_to_vfp_compare(env, \ FLOATTYPE ## _compare_quiet(a, b, &env->vfp.FPST)); \ } \ void VFP_HELPER(cmpe, P)(ARGTYPE a, ARGTYPE b, CPUARMState *env) \ { \ softfloat_to_vfp_compare(env, \ FLOATTYPE ## _compare(a, b, &env->vfp.FPST)); \ } DO_VFP_cmp(h, float16, dh_ctype_f16, fp_status_f16) DO_VFP_cmp(s, float32, float32, fp_status) DO_VFP_cmp(d, float64, float64, fp_status) #undef DO_VFP_cmp /* Integer to float and float to integer conversions */ #define CONV_ITOF(name, ftype, fsz, sign) \ ftype HELPER(name)(uint32_t x, void *fpstp) \ { \ float_status *fpst = fpstp; \ return sign##int32_to_##float##fsz((sign##int32_t)x, fpst); \ } #define CONV_FTOI(name, ftype, fsz, sign, round) \ sign##int32_t HELPER(name)(ftype x, void *fpstp) \ { \ float_status *fpst = fpstp; \ if (float##fsz##_is_any_nan(x)) { \ float_raise(float_flag_invalid, fpst); \ return 0; \ } \ return float##fsz##_to_##sign##int32##round(x, fpst); \ } #define FLOAT_CONVS(name, p, ftype, fsz, sign) \ CONV_ITOF(vfp_##name##to##p, ftype, fsz, sign) \ CONV_FTOI(vfp_to##name##p, ftype, fsz, sign, ) \ CONV_FTOI(vfp_to##name##z##p, ftype, fsz, sign, _round_to_zero) FLOAT_CONVS(si, h, uint32_t, 16, ) FLOAT_CONVS(si, s, float32, 32, ) FLOAT_CONVS(si, d, float64, 64, ) FLOAT_CONVS(ui, h, uint32_t, 16, u) FLOAT_CONVS(ui, s, float32, 32, u) FLOAT_CONVS(ui, d, float64, 64, u) #undef CONV_ITOF #undef CONV_FTOI #undef FLOAT_CONVS /* floating point conversion */ float64 VFP_HELPER(fcvtd, s)(float32 x, CPUARMState *env) { return float32_to_float64(x, &env->vfp.fp_status); } float32 VFP_HELPER(fcvts, d)(float64 x, CPUARMState *env) { return float64_to_float32(x, &env->vfp.fp_status); } uint32_t HELPER(bfcvt)(float32 x, void *status) { return float32_to_bfloat16(x, status); } uint32_t HELPER(bfcvt_pair)(uint64_t pair, void *status) { bfloat16 lo = float32_to_bfloat16(extract64(pair, 0, 32), status); bfloat16 hi = float32_to_bfloat16(extract64(pair, 32, 32), status); return deposit32(lo, 16, 16, hi); } /* * VFP3 fixed point conversion. The AArch32 versions of fix-to-float * must always round-to-nearest; the AArch64 ones honour the FPSCR * rounding mode. (For AArch32 Neon the standard-FPSCR is set to * round-to-nearest so either helper will work.) AArch32 float-to-fix * must round-to-zero. */ #define VFP_CONV_FIX_FLOAT(name, p, fsz, ftype, isz, itype) \ ftype HELPER(vfp_##name##to##p)(uint##isz##_t x, uint32_t shift, \ void *fpstp) \ { return itype##_to_##float##fsz##_scalbn(x, -shift, fpstp); } #define VFP_CONV_FIX_FLOAT_ROUND(name, p, fsz, ftype, isz, itype) \ ftype HELPER(vfp_##name##to##p##_round_to_nearest)(uint##isz##_t x, \ uint32_t shift, \ void *fpstp) \ { \ ftype ret; \ float_status *fpst = fpstp; \ FloatRoundMode oldmode = fpst->float_rounding_mode; \ fpst->float_rounding_mode = float_round_nearest_even; \ ret = itype##_to_##float##fsz##_scalbn(x, -shift, fpstp); \ fpst->float_rounding_mode = oldmode; \ return ret; \ } #define VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, ftype, isz, itype, ROUND, suff) \ uint##isz##_t HELPER(vfp_to##name##p##suff)(ftype x, uint32_t shift, \ void *fpst) \ { \ if (unlikely(float##fsz##_is_any_nan(x))) { \ float_raise(float_flag_invalid, fpst); \ return 0; \ } \ return float##fsz##_to_##itype##_scalbn(x, ROUND, shift, fpst); \ } #define VFP_CONV_FIX(name, p, fsz, ftype, isz, itype) \ VFP_CONV_FIX_FLOAT(name, p, fsz, ftype, isz, itype) \ VFP_CONV_FIX_FLOAT_ROUND(name, p, fsz, ftype, isz, itype) \ VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, ftype, isz, itype, \ float_round_to_zero, _round_to_zero) \ VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, ftype, isz, itype, \ get_float_rounding_mode(fpst), ) #define VFP_CONV_FIX_A64(name, p, fsz, ftype, isz, itype) \ VFP_CONV_FIX_FLOAT(name, p, fsz, ftype, isz, itype) \ VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, ftype, isz, itype, \ get_float_rounding_mode(fpst), ) VFP_CONV_FIX(sh, d, 64, float64, 64, int16) VFP_CONV_FIX(sl, d, 64, float64, 64, int32) VFP_CONV_FIX_A64(sq, d, 64, float64, 64, int64) VFP_CONV_FIX(uh, d, 64, float64, 64, uint16) VFP_CONV_FIX(ul, d, 64, float64, 64, uint32) VFP_CONV_FIX_A64(uq, d, 64, float64, 64, uint64) VFP_CONV_FIX(sh, s, 32, float32, 32, int16) VFP_CONV_FIX(sl, s, 32, float32, 32, int32) VFP_CONV_FIX_A64(sq, s, 32, float32, 64, int64) VFP_CONV_FIX(uh, s, 32, float32, 32, uint16) VFP_CONV_FIX(ul, s, 32, float32, 32, uint32) VFP_CONV_FIX_A64(uq, s, 32, float32, 64, uint64) VFP_CONV_FIX(sh, h, 16, dh_ctype_f16, 32, int16) VFP_CONV_FIX(sl, h, 16, dh_ctype_f16, 32, int32) VFP_CONV_FIX_A64(sq, h, 16, dh_ctype_f16, 64, int64) VFP_CONV_FIX(uh, h, 16, dh_ctype_f16, 32, uint16) VFP_CONV_FIX(ul, h, 16, dh_ctype_f16, 32, uint32) VFP_CONV_FIX_A64(uq, h, 16, dh_ctype_f16, 64, uint64) #undef VFP_CONV_FIX #undef VFP_CONV_FIX_FLOAT #undef VFP_CONV_FLOAT_FIX_ROUND #undef VFP_CONV_FIX_A64 /* Set the current fp rounding mode and return the old one. * The argument is a softfloat float_round_ value. */ uint32_t HELPER(set_rmode)(uint32_t rmode, void *fpstp) { float_status *fp_status = fpstp; uint32_t prev_rmode = get_float_rounding_mode(fp_status); set_float_rounding_mode(rmode, fp_status); return prev_rmode; } /* Half precision conversions. */ float32 HELPER(vfp_fcvt_f16_to_f32)(uint32_t a, void *fpstp, uint32_t ahp_mode) { /* Squash FZ16 to 0 for the duration of conversion. In this case, * it would affect flushing input denormals. */ float_status *fpst = fpstp; bool save = get_flush_inputs_to_zero(fpst); set_flush_inputs_to_zero(false, fpst); float32 r = float16_to_float32(a, !ahp_mode, fpst); set_flush_inputs_to_zero(save, fpst); return r; } uint32_t HELPER(vfp_fcvt_f32_to_f16)(float32 a, void *fpstp, uint32_t ahp_mode) { /* Squash FZ16 to 0 for the duration of conversion. In this case, * it would affect flushing output denormals. */ float_status *fpst = fpstp; bool save = get_flush_to_zero(fpst); set_flush_to_zero(false, fpst); float16 r = float32_to_float16(a, !ahp_mode, fpst); set_flush_to_zero(save, fpst); return r; } float64 HELPER(vfp_fcvt_f16_to_f64)(uint32_t a, void *fpstp, uint32_t ahp_mode) { /* Squash FZ16 to 0 for the duration of conversion. In this case, * it would affect flushing input denormals. */ float_status *fpst = fpstp; bool save = get_flush_inputs_to_zero(fpst); set_flush_inputs_to_zero(false, fpst); float64 r = float16_to_float64(a, !ahp_mode, fpst); set_flush_inputs_to_zero(save, fpst); return r; } uint32_t HELPER(vfp_fcvt_f64_to_f16)(float64 a, void *fpstp, uint32_t ahp_mode) { /* Squash FZ16 to 0 for the duration of conversion. In this case, * it would affect flushing output denormals. */ float_status *fpst = fpstp; bool save = get_flush_to_zero(fpst); set_flush_to_zero(false, fpst); float16 r = float64_to_float16(a, !ahp_mode, fpst); set_flush_to_zero(save, fpst); return r; } /* NEON helpers. */ /* Constants 256 and 512 are used in some helpers; we avoid relying on * int->float conversions at run-time. */ #define float64_256 make_float64(0x4070000000000000LL) #define float64_512 make_float64(0x4080000000000000LL) #define float16_maxnorm make_float16(0x7bff) #define float32_maxnorm make_float32(0x7f7fffff) #define float64_maxnorm make_float64(0x7fefffffffffffffLL) /* Reciprocal functions * * The algorithm that must be used to calculate the estimate * is specified by the ARM ARM, see FPRecipEstimate()/RecipEstimate */ /* See RecipEstimate() * * input is a 9 bit fixed point number * input range 256 .. 511 for a number from 0.5 <= x < 1.0. * result range 256 .. 511 for a number from 1.0 to 511/256. */ static int recip_estimate(int input) { int a, b, r; assert(256 <= input && input < 512); a = (input * 2) + 1; b = (1 << 19) / a; r = (b + 1) >> 1; assert(256 <= r && r < 512); return r; } /* * Common wrapper to call recip_estimate * * The parameters are exponent and 64 bit fraction (without implicit * bit) where the binary point is nominally at bit 52. Returns a * float64 which can then be rounded to the appropriate size by the * callee. */ static uint64_t call_recip_estimate(int *exp, int exp_off, uint64_t frac) { uint32_t scaled, estimate; uint64_t result_frac; int result_exp; /* Handle sub-normals */ if (*exp == 0) { if (extract64(frac, 51, 1) == 0) { *exp = -1; frac <<= 2; } else { frac <<= 1; } } /* scaled = UInt('1':fraction<51:44>) */ scaled = deposit32(1 << 8, 0, 8, extract64(frac, 44, 8)); estimate = recip_estimate(scaled); result_exp = exp_off - *exp; result_frac = deposit64(0, 44, 8, estimate); if (result_exp == 0) { result_frac = deposit64(result_frac >> 1, 51, 1, 1); } else if (result_exp == -1) { result_frac = deposit64(result_frac >> 2, 50, 2, 1); result_exp = 0; } *exp = result_exp; return result_frac; } static bool round_to_inf(float_status *fpst, bool sign_bit) { switch (fpst->float_rounding_mode) { case float_round_nearest_even: /* Round to Nearest */ return true; case float_round_up: /* Round to +Inf */ return !sign_bit; case float_round_down: /* Round to -Inf */ return sign_bit; case float_round_to_zero: /* Round to Zero */ return false; default: g_assert_not_reached(); } } uint32_t HELPER(recpe_f16)(uint32_t input, void *fpstp) { float_status *fpst = fpstp; float16 f16 = float16_squash_input_denormal(input, fpst); uint32_t f16_val = float16_val(f16); uint32_t f16_sign = float16_is_neg(f16); int f16_exp = extract32(f16_val, 10, 5); uint32_t f16_frac = extract32(f16_val, 0, 10); uint64_t f64_frac; if (float16_is_any_nan(f16)) { float16 nan = f16; if (float16_is_signaling_nan(f16, fpst)) { float_raise(float_flag_invalid, fpst); nan = float16_silence_nan(f16, fpst); } if (fpst->default_nan_mode) { nan = float16_default_nan(fpst); } return nan; } else if (float16_is_infinity(f16)) { return float16_set_sign(float16_zero, float16_is_neg(f16)); } else if (float16_is_zero(f16)) { float_raise(float_flag_divbyzero, fpst); return float16_set_sign(float16_infinity, float16_is_neg(f16)); } else if (float16_abs(f16) < (1 << 8)) { /* Abs(value) < 2.0^-16 */ float_raise(float_flag_overflow | float_flag_inexact, fpst); if (round_to_inf(fpst, f16_sign)) { return float16_set_sign(float16_infinity, f16_sign); } else { return float16_set_sign(float16_maxnorm, f16_sign); } } else if (f16_exp >= 29 && fpst->flush_to_zero) { float_raise(float_flag_underflow, fpst); return float16_set_sign(float16_zero, float16_is_neg(f16)); } f64_frac = call_recip_estimate(&f16_exp, 29, ((uint64_t) f16_frac) << (52 - 10)); /* result = sign : result_exp<4:0> : fraction<51:42> */ f16_val = deposit32(0, 15, 1, f16_sign); f16_val = deposit32(f16_val, 10, 5, f16_exp); f16_val = deposit32(f16_val, 0, 10, extract64(f64_frac, 52 - 10, 10)); return make_float16(f16_val); } float32 HELPER(recpe_f32)(float32 input, void *fpstp) { float_status *fpst = fpstp; float32 f32 = float32_squash_input_denormal(input, fpst); uint32_t f32_val = float32_val(f32); bool f32_sign = float32_is_neg(f32); int f32_exp = extract32(f32_val, 23, 8); uint32_t f32_frac = extract32(f32_val, 0, 23); uint64_t f64_frac; if (float32_is_any_nan(f32)) { float32 nan = f32; if (float32_is_signaling_nan(f32, fpst)) { float_raise(float_flag_invalid, fpst); nan = float32_silence_nan(f32, fpst); } if (fpst->default_nan_mode) { nan = float32_default_nan(fpst); } return nan; } else if (float32_is_infinity(f32)) { return float32_set_sign(float32_zero, float32_is_neg(f32)); } else if (float32_is_zero(f32)) { float_raise(float_flag_divbyzero, fpst); return float32_set_sign(float32_infinity, float32_is_neg(f32)); } else if (float32_abs(f32) < (1ULL << 21)) { /* Abs(value) < 2.0^-128 */ float_raise(float_flag_overflow | float_flag_inexact, fpst); if (round_to_inf(fpst, f32_sign)) { return float32_set_sign(float32_infinity, f32_sign); } else { return float32_set_sign(float32_maxnorm, f32_sign); } } else if (f32_exp >= 253 && fpst->flush_to_zero) { float_raise(float_flag_underflow, fpst); return float32_set_sign(float32_zero, float32_is_neg(f32)); } f64_frac = call_recip_estimate(&f32_exp, 253, ((uint64_t) f32_frac) << (52 - 23)); /* result = sign : result_exp<7:0> : fraction<51:29> */ f32_val = deposit32(0, 31, 1, f32_sign); f32_val = deposit32(f32_val, 23, 8, f32_exp); f32_val = deposit32(f32_val, 0, 23, extract64(f64_frac, 52 - 23, 23)); return make_float32(f32_val); } float64 HELPER(recpe_f64)(float64 input, void *fpstp) { float_status *fpst = fpstp; float64 f64 = float64_squash_input_denormal(input, fpst); uint64_t f64_val = float64_val(f64); bool f64_sign = float64_is_neg(f64); int f64_exp = extract64(f64_val, 52, 11); uint64_t f64_frac = extract64(f64_val, 0, 52); /* Deal with any special cases */ if (float64_is_any_nan(f64)) { float64 nan = f64; if (float64_is_signaling_nan(f64, fpst)) { float_raise(float_flag_invalid, fpst); nan = float64_silence_nan(f64, fpst); } if (fpst->default_nan_mode) { nan = float64_default_nan(fpst); } return nan; } else if (float64_is_infinity(f64)) { return float64_set_sign(float64_zero, float64_is_neg(f64)); } else if (float64_is_zero(f64)) { float_raise(float_flag_divbyzero, fpst); return float64_set_sign(float64_infinity, float64_is_neg(f64)); } else if ((f64_val & ~(1ULL << 63)) < (1ULL << 50)) { /* Abs(value) < 2.0^-1024 */ float_raise(float_flag_overflow | float_flag_inexact, fpst); if (round_to_inf(fpst, f64_sign)) { return float64_set_sign(float64_infinity, f64_sign); } else { return float64_set_sign(float64_maxnorm, f64_sign); } } else if (f64_exp >= 2045 && fpst->flush_to_zero) { float_raise(float_flag_underflow, fpst); return float64_set_sign(float64_zero, float64_is_neg(f64)); } f64_frac = call_recip_estimate(&f64_exp, 2045, f64_frac); /* result = sign : result_exp<10:0> : fraction<51:0>; */ f64_val = deposit64(0, 63, 1, f64_sign); f64_val = deposit64(f64_val, 52, 11, f64_exp); f64_val = deposit64(f64_val, 0, 52, f64_frac); return make_float64(f64_val); } /* The algorithm that must be used to calculate the estimate * is specified by the ARM ARM. */ static int do_recip_sqrt_estimate(int a) { int b, estimate; assert(128 <= a && a < 512); if (a < 256) { a = a * 2 + 1; } else { a = (a >> 1) << 1; a = (a + 1) * 2; } b = 512; while (a * (b + 1) * (b + 1) < (1 << 28)) { b += 1; } estimate = (b + 1) / 2; assert(256 <= estimate && estimate < 512); return estimate; } static uint64_t recip_sqrt_estimate(int *exp , int exp_off, uint64_t frac) { int estimate; uint32_t scaled; if (*exp == 0) { while (extract64(frac, 51, 1) == 0) { frac = frac << 1; *exp -= 1; } frac = extract64(frac, 0, 51) << 1; } if (*exp & 1) { /* scaled = UInt('01':fraction<51:45>) */ scaled = deposit32(1 << 7, 0, 7, extract64(frac, 45, 7)); } else { /* scaled = UInt('1':fraction<51:44>) */ scaled = deposit32(1 << 8, 0, 8, extract64(frac, 44, 8)); } estimate = do_recip_sqrt_estimate(scaled); *exp = (exp_off - *exp) / 2; return extract64(estimate, 0, 8) << 44; } uint32_t HELPER(rsqrte_f16)(uint32_t input, void *fpstp) { float_status *s = fpstp; float16 f16 = float16_squash_input_denormal(input, s); uint16_t val = float16_val(f16); bool f16_sign = float16_is_neg(f16); int f16_exp = extract32(val, 10, 5); uint16_t f16_frac = extract32(val, 0, 10); uint64_t f64_frac; if (float16_is_any_nan(f16)) { float16 nan = f16; if (float16_is_signaling_nan(f16, s)) { float_raise(float_flag_invalid, s); nan = float16_silence_nan(f16, s); } if (s->default_nan_mode) { nan = float16_default_nan(s); } return nan; } else if (float16_is_zero(f16)) { float_raise(float_flag_divbyzero, s); return float16_set_sign(float16_infinity, f16_sign); } else if (f16_sign) { float_raise(float_flag_invalid, s); return float16_default_nan(s); } else if (float16_is_infinity(f16)) { return float16_zero; } /* Scale and normalize to a double-precision value between 0.25 and 1.0, * preserving the parity of the exponent. */ f64_frac = ((uint64_t) f16_frac) << (52 - 10); f64_frac = recip_sqrt_estimate(&f16_exp, 44, f64_frac); /* result = sign : result_exp<4:0> : estimate<7:0> : Zeros(2) */ val = deposit32(0, 15, 1, f16_sign); val = deposit32(val, 10, 5, f16_exp); val = deposit32(val, 2, 8, extract64(f64_frac, 52 - 8, 8)); return make_float16(val); } float32 HELPER(rsqrte_f32)(float32 input, void *fpstp) { float_status *s = fpstp; float32 f32 = float32_squash_input_denormal(input, s); uint32_t val = float32_val(f32); uint32_t f32_sign = float32_is_neg(f32); int f32_exp = extract32(val, 23, 8); uint32_t f32_frac = extract32(val, 0, 23); uint64_t f64_frac; if (float32_is_any_nan(f32)) { float32 nan = f32; if (float32_is_signaling_nan(f32, s)) { float_raise(float_flag_invalid, s); nan = float32_silence_nan(f32, s); } if (s->default_nan_mode) { nan = float32_default_nan(s); } return nan; } else if (float32_is_zero(f32)) { float_raise(float_flag_divbyzero, s); return float32_set_sign(float32_infinity, float32_is_neg(f32)); } else if (float32_is_neg(f32)) { float_raise(float_flag_invalid, s); return float32_default_nan(s); } else if (float32_is_infinity(f32)) { return float32_zero; } /* Scale and normalize to a double-precision value between 0.25 and 1.0, * preserving the parity of the exponent. */ f64_frac = ((uint64_t) f32_frac) << 29; f64_frac = recip_sqrt_estimate(&f32_exp, 380, f64_frac); /* result = sign : result_exp<4:0> : estimate<7:0> : Zeros(15) */ val = deposit32(0, 31, 1, f32_sign); val = deposit32(val, 23, 8, f32_exp); val = deposit32(val, 15, 8, extract64(f64_frac, 52 - 8, 8)); return make_float32(val); } float64 HELPER(rsqrte_f64)(float64 input, void *fpstp) { float_status *s = fpstp; float64 f64 = float64_squash_input_denormal(input, s); uint64_t val = float64_val(f64); bool f64_sign = float64_is_neg(f64); int f64_exp = extract64(val, 52, 11); uint64_t f64_frac = extract64(val, 0, 52); if (float64_is_any_nan(f64)) { float64 nan = f64; if (float64_is_signaling_nan(f64, s)) { float_raise(float_flag_invalid, s); nan = float64_silence_nan(f64, s); } if (s->default_nan_mode) { nan = float64_default_nan(s); } return nan; } else if (float64_is_zero(f64)) { float_raise(float_flag_divbyzero, s); return float64_set_sign(float64_infinity, float64_is_neg(f64)); } else if (float64_is_neg(f64)) { float_raise(float_flag_invalid, s); return float64_default_nan(s); } else if (float64_is_infinity(f64)) { return float64_zero; } f64_frac = recip_sqrt_estimate(&f64_exp, 3068, f64_frac); /* result = sign : result_exp<4:0> : estimate<7:0> : Zeros(44) */ val = deposit64(0, 61, 1, f64_sign); val = deposit64(val, 52, 11, f64_exp); val = deposit64(val, 44, 8, extract64(f64_frac, 52 - 8, 8)); return make_float64(val); } uint32_t HELPER(recpe_u32)(uint32_t a) { int input, estimate; if ((a & 0x80000000) == 0) { return 0xffffffff; } input = extract32(a, 23, 9); estimate = recip_estimate(input); return deposit32(0, (32 - 9), 9, estimate); } uint32_t HELPER(rsqrte_u32)(uint32_t a) { int estimate; if ((a & 0xc0000000) == 0) { return 0xffffffff; } estimate = do_recip_sqrt_estimate(extract32(a, 23, 9)); return deposit32(0, 23, 9, estimate); } /* VFPv4 fused multiply-accumulate */ dh_ctype_f16 VFP_HELPER(muladd, h)(dh_ctype_f16 a, dh_ctype_f16 b, dh_ctype_f16 c, void *fpstp) { float_status *fpst = fpstp; return float16_muladd(a, b, c, 0, fpst); } float32 VFP_HELPER(muladd, s)(float32 a, float32 b, float32 c, void *fpstp) { float_status *fpst = fpstp; return float32_muladd(a, b, c, 0, fpst); } float64 VFP_HELPER(muladd, d)(float64 a, float64 b, float64 c, void *fpstp) { float_status *fpst = fpstp; return float64_muladd(a, b, c, 0, fpst); } /* ARMv8 round to integral */ dh_ctype_f16 HELPER(rinth_exact)(dh_ctype_f16 x, void *fp_status) { return float16_round_to_int(x, fp_status); } float32 HELPER(rints_exact)(float32 x, void *fp_status) { return float32_round_to_int(x, fp_status); } float64 HELPER(rintd_exact)(float64 x, void *fp_status) { return float64_round_to_int(x, fp_status); } dh_ctype_f16 HELPER(rinth)(dh_ctype_f16 x, void *fp_status) { int old_flags = get_float_exception_flags(fp_status), new_flags; float16 ret; ret = float16_round_to_int(x, fp_status); /* Suppress any inexact exceptions the conversion produced */ if (!(old_flags & float_flag_inexact)) { new_flags = get_float_exception_flags(fp_status); set_float_exception_flags(new_flags & ~float_flag_inexact, fp_status); } return ret; } float32 HELPER(rints)(float32 x, void *fp_status) { int old_flags = get_float_exception_flags(fp_status), new_flags; float32 ret; ret = float32_round_to_int(x, fp_status); /* Suppress any inexact exceptions the conversion produced */ if (!(old_flags & float_flag_inexact)) { new_flags = get_float_exception_flags(fp_status); set_float_exception_flags(new_flags & ~float_flag_inexact, fp_status); } return ret; } float64 HELPER(rintd)(float64 x, void *fp_status) { int old_flags = get_float_exception_flags(fp_status), new_flags; float64 ret; ret = float64_round_to_int(x, fp_status); new_flags = get_float_exception_flags(fp_status); /* Suppress any inexact exceptions the conversion produced */ if (!(old_flags & float_flag_inexact)) { new_flags = get_float_exception_flags(fp_status); set_float_exception_flags(new_flags & ~float_flag_inexact, fp_status); } return ret; } /* Convert ARM rounding mode to softfloat */ int arm_rmode_to_sf(int rmode) { switch (rmode) { case FPROUNDING_TIEAWAY: rmode = float_round_ties_away; break; case FPROUNDING_ODD: /* FIXME: add support for TIEAWAY and ODD */ qemu_log_mask(LOG_UNIMP, "arm: unimplemented rounding mode: %d\n", rmode); /* fall through for now */ case FPROUNDING_TIEEVEN: default: rmode = float_round_nearest_even; break; case FPROUNDING_POSINF: rmode = float_round_up; break; case FPROUNDING_NEGINF: rmode = float_round_down; break; case FPROUNDING_ZERO: rmode = float_round_to_zero; break; } return rmode; } /* * Implement float64 to int32_t conversion without saturation; * the result is supplied modulo 2^32. */ uint64_t HELPER(fjcvtzs)(float64 value, void *vstatus) { float_status *status = vstatus; uint32_t exp, sign; uint64_t frac; uint32_t inexact = 1; /* !Z */ sign = extract64(value, 63, 1); exp = extract64(value, 52, 11); frac = extract64(value, 0, 52); if (exp == 0) { /* While not inexact for IEEE FP, -0.0 is inexact for JavaScript. */ inexact = sign; if (frac != 0) { if (status->flush_inputs_to_zero) { float_raise(float_flag_input_denormal, status); } else { float_raise(float_flag_inexact, status); inexact = 1; } } frac = 0; } else if (exp == 0x7ff) { /* This operation raises Invalid for both NaN and overflow (Inf). */ float_raise(float_flag_invalid, status); frac = 0; } else { int true_exp = exp - 1023; int shift = true_exp - 52; /* Restore implicit bit. */ frac |= 1ull << 52; /* Shift the fraction into place. */ if (shift >= 0) { /* The number is so large we must shift the fraction left. */ if (shift >= 64) { /* The fraction is shifted out entirely. */ frac = 0; } else { frac <<= shift; } } else if (shift > -64) { /* Normal case -- shift right and notice if bits shift out. */ inexact = (frac << (64 + shift)) != 0; frac >>= -shift; } else { /* The fraction is shifted out entirely. */ frac = 0; } /* Notice overflow or inexact exceptions. */ if (true_exp > 31 || frac > (sign ? 0x80000000ull : 0x7fffffff)) { /* Overflow, for which this operation raises invalid. */ float_raise(float_flag_invalid, status); inexact = 1; } else if (inexact) { float_raise(float_flag_inexact, status); } /* Honor the sign. */ if (sign) { frac = -frac; } } /* Pack the result and the env->ZF representation of Z together. */ return deposit64(frac, 32, 32, inexact); } uint32_t HELPER(vjcvt)(float64 value, CPUARMState *env) { uint64_t pair = HELPER(fjcvtzs)(value, &env->vfp.fp_status); uint32_t result = pair; uint32_t z = (pair >> 32) == 0; /* Store Z, clear NCV, in FPSCR.NZCV. */ env->vfp.xregs[ARM_VFP_FPSCR] = (env->vfp.xregs[ARM_VFP_FPSCR] & ~CPSR_NZCV) | (z * CPSR_Z); return result; } /* Round a float32 to an integer that fits in int32_t or int64_t. */ static float32 frint_s(float32 f, float_status *fpst, int intsize) { int old_flags = get_float_exception_flags(fpst); uint32_t exp = extract32(f, 23, 8); if (unlikely(exp == 0xff)) { /* NaN or Inf. */ goto overflow; } /* Round and re-extract the exponent. */ f = float32_round_to_int(f, fpst); exp = extract32(f, 23, 8); /* Validate the range of the result. */ if (exp < 126 + intsize) { /* abs(F) <= INT{N}_MAX */ return f; } if (exp == 126 + intsize) { uint32_t sign = extract32(f, 31, 1); uint32_t frac = extract32(f, 0, 23); if (sign && frac == 0) { /* F == INT{N}_MIN */ return f; } } overflow: /* * Raise Invalid and return INT{N}_MIN as a float. Revert any * inexact exception float32_round_to_int may have raised. */ set_float_exception_flags(old_flags | float_flag_invalid, fpst); return (0x100u + 126u + intsize) << 23; } float32 HELPER(frint32_s)(float32 f, void *fpst) { return frint_s(f, fpst, 32); } float32 HELPER(frint64_s)(float32 f, void *fpst) { return frint_s(f, fpst, 64); } /* Round a float64 to an integer that fits in int32_t or int64_t. */ static float64 frint_d(float64 f, float_status *fpst, int intsize) { int old_flags = get_float_exception_flags(fpst); uint32_t exp = extract64(f, 52, 11); if (unlikely(exp == 0x7ff)) { /* NaN or Inf. */ goto overflow; } /* Round and re-extract the exponent. */ f = float64_round_to_int(f, fpst); exp = extract64(f, 52, 11); /* Validate the range of the result. */ if (exp < 1022 + intsize) { /* abs(F) <= INT{N}_MAX */ return f; } if (exp == 1022 + intsize) { uint64_t sign = extract64(f, 63, 1); uint64_t frac = extract64(f, 0, 52); if (sign && frac == 0) { /* F == INT{N}_MIN */ return f; } } overflow: /* * Raise Invalid and return INT{N}_MIN as a float. Revert any * inexact exception float64_round_to_int may have raised. */ set_float_exception_flags(old_flags | float_flag_invalid, fpst); return (uint64_t)(0x800 + 1022 + intsize) << 52; } float64 HELPER(frint32_d)(float64 f, void *fpst) { return frint_d(f, fpst, 32); } float64 HELPER(frint64_d)(float64 f, void *fpst) { return frint_d(f, fpst, 64); } void HELPER(check_hcr_el2_trap)(CPUARMState *env, uint32_t rt, uint32_t reg) { uint32_t syndrome; switch (reg) { case ARM_VFP_MVFR0: case ARM_VFP_MVFR1: case ARM_VFP_MVFR2: if (!(arm_hcr_el2_eff(env) & HCR_TID3)) { return; } break; case ARM_VFP_FPSID: if (!(arm_hcr_el2_eff(env) & HCR_TID0)) { return; } break; default: g_assert_not_reached(); } syndrome = ((EC_FPIDTRAP << ARM_EL_EC_SHIFT) | ARM_EL_IL | (1 << 24) | (0xe << 20) | (7 << 14) | (reg << 10) | (rt << 5) | 1); raise_exception(env, EXCP_HYP_TRAP, syndrome, 2); } #endif