diff options
Diffstat (limited to 'fpu')
| -rw-r--r-- | fpu/softfloat.c | 132 |
1 files changed, 128 insertions, 4 deletions
diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 82294458fe..7554d63495 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -1518,8 +1518,9 @@ float16 QEMU_FLATTEN float16_muladd(float16 a, float16 b, float16 c, return float16_round_pack_canonical(pr, status); } -float32 QEMU_FLATTEN float32_muladd(float32 a, float32 b, float32 c, - int flags, float_status *status) +static float32 QEMU_SOFTFLOAT_ATTR +soft_f32_muladd(float32 a, float32 b, float32 c, int flags, + float_status *status) { FloatParts pa = float32_unpack_canonical(a, status); FloatParts pb = float32_unpack_canonical(b, status); @@ -1529,8 +1530,9 @@ float32 QEMU_FLATTEN float32_muladd(float32 a, float32 b, float32 c, return float32_round_pack_canonical(pr, status); } -float64 QEMU_FLATTEN float64_muladd(float64 a, float64 b, float64 c, - int flags, float_status *status) +static float64 QEMU_SOFTFLOAT_ATTR +soft_f64_muladd(float64 a, float64 b, float64 c, int flags, + float_status *status) { FloatParts pa = float64_unpack_canonical(a, status); FloatParts pb = float64_unpack_canonical(b, status); @@ -1540,6 +1542,128 @@ float64 QEMU_FLATTEN float64_muladd(float64 a, float64 b, float64 c, return float64_round_pack_canonical(pr, status); } +float32 QEMU_FLATTEN +float32_muladd(float32 xa, float32 xb, float32 xc, int flags, float_status *s) +{ + union_float32 ua, ub, uc, ur; + + ua.s = xa; + ub.s = xb; + uc.s = xc; + + if (unlikely(!can_use_fpu(s))) { + goto soft; + } + if (unlikely(flags & float_muladd_halve_result)) { + goto soft; + } + + float32_input_flush3(&ua.s, &ub.s, &uc.s, s); + if (unlikely(!f32_is_zon3(ua, ub, uc))) { + goto soft; + } + /* + * When (a || b) == 0, there's no need to check for under/over flow, + * since we know the addend is (normal || 0) and the product is 0. + */ + if (float32_is_zero(ua.s) || float32_is_zero(ub.s)) { + union_float32 up; + bool prod_sign; + + prod_sign = float32_is_neg(ua.s) ^ float32_is_neg(ub.s); + prod_sign ^= !!(flags & float_muladd_negate_product); + up.s = float32_set_sign(float32_zero, prod_sign); + + if (flags & float_muladd_negate_c) { + uc.h = -uc.h; + } + ur.h = up.h + uc.h; + } else { + if (flags & float_muladd_negate_product) { + ua.h = -ua.h; + } + if (flags & float_muladd_negate_c) { + uc.h = -uc.h; + } + + ur.h = fmaf(ua.h, ub.h, uc.h); + + if (unlikely(f32_is_inf(ur))) { + s->float_exception_flags |= float_flag_overflow; + } else if (unlikely(fabsf(ur.h) <= FLT_MIN)) { + goto soft; + } + } + if (flags & float_muladd_negate_result) { + return float32_chs(ur.s); + } + return ur.s; + + soft: + return soft_f32_muladd(ua.s, ub.s, uc.s, flags, s); +} + +float64 QEMU_FLATTEN +float64_muladd(float64 xa, float64 xb, float64 xc, int flags, float_status *s) +{ + union_float64 ua, ub, uc, ur; + + ua.s = xa; + ub.s = xb; + uc.s = xc; + + if (unlikely(!can_use_fpu(s))) { + goto soft; + } + if (unlikely(flags & float_muladd_halve_result)) { + goto soft; + } + + float64_input_flush3(&ua.s, &ub.s, &uc.s, s); + if (unlikely(!f64_is_zon3(ua, ub, uc))) { + goto soft; + } + /* + * When (a || b) == 0, there's no need to check for under/over flow, + * since we know the addend is (normal || 0) and the product is 0. + */ + if (float64_is_zero(ua.s) || float64_is_zero(ub.s)) { + union_float64 up; + bool prod_sign; + + prod_sign = float64_is_neg(ua.s) ^ float64_is_neg(ub.s); + prod_sign ^= !!(flags & float_muladd_negate_product); + up.s = float64_set_sign(float64_zero, prod_sign); + + if (flags & float_muladd_negate_c) { + uc.h = -uc.h; + } + ur.h = up.h + uc.h; + } else { + if (flags & float_muladd_negate_product) { + ua.h = -ua.h; + } + if (flags & float_muladd_negate_c) { + uc.h = -uc.h; + } + + ur.h = fma(ua.h, ub.h, uc.h); + + if (unlikely(f64_is_inf(ur))) { + s->float_exception_flags |= float_flag_overflow; + } else if (unlikely(fabs(ur.h) <= FLT_MIN)) { + goto soft; + } + } + if (flags & float_muladd_negate_result) { + return float64_chs(ur.s); + } + return ur.s; + + soft: + return soft_f64_muladd(ua.s, ub.s, uc.s, flags, s); +} + /* * Returns the result of dividing the floating-point value `a' by the * corresponding value `b'. The operation is performed according to |