motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-01 14:53:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

softfloat: add APIs to handle alternative sNaN propagation for fmax/fmin

Browse source 
For "fmax/fmin ft0, ft1, ft2" and if one of the inputs is sNaN,

  The original logic:
    Return NaN and set invalid flag if ft1 == sNaN || ft2 == sNan.

  The alternative path:
    Set invalid flag if ft1 == sNaN || ft2 == sNaN.
    Return NaN only if ft1 == NaN && ft2 == NaN.

The IEEE 754 spec allows both implementation and some architecture such
as riscv choose different defintions in two spec versions.
(riscv-spec-v2.2 use original version, riscv-spec-20191213 changes to
 alternative)

Signed-off-by: Chih-Min Chao <chihmin.chao@sifive.com>
Signed-off-by: Frank Chang <frank.chang@sifive.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211021160847.2748577-2-frank.chang@sifive.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
This commit is contained in:
Chih-Min Chao 2021-10-22 00:08:45 +08:00 • committed by Alistair Francis
parent 50d1608764
commit 0e9030376e
3 changed files with 46 additions and 8 deletions
Download patch file Download diff file Expand all files Collapse all files

10
include/fpu/softfloat.h
View file

@ -243,6 +243,8 @@ float16 float16_minnum(float16, float16, float_status *status);
float16 float16_maxnum(float16, float16, float_status *status);
float16 float16_minnummag(float16, float16, float_status *status);
float16 float16_maxnummag(float16, float16, float_status *status);
float16 float16_minimum_number(float16, float16, float_status *status);
float16 float16_maximum_number(float16, float16, float_status *status);
float16 float16_sqrt(float16, float_status *status);
FloatRelation float16_compare(float16, float16, float_status *status);
FloatRelation float16_compare_quiet(float16, float16, float_status *status);
@ -422,6 +424,8 @@ bfloat16 bfloat16_minnum(bfloat16, bfloat16, float_status *status);
bfloat16 bfloat16_maxnum(bfloat16, bfloat16, float_status *status);
bfloat16 bfloat16_minnummag(bfloat16, bfloat16, float_status *status);
bfloat16 bfloat16_maxnummag(bfloat16, bfloat16, float_status *status);
bfloat16 bfloat16_minimum_number(bfloat16, bfloat16, float_status *status);
bfloat16 bfloat16_maximum_number(bfloat16, bfloat16, float_status *status);
bfloat16 bfloat16_sqrt(bfloat16, float_status *status);
FloatRelation bfloat16_compare(bfloat16, bfloat16, float_status *status);
FloatRelation bfloat16_compare_quiet(bfloat16, bfloat16, float_status *status);
@ -589,6 +593,8 @@ float32 float32_minnum(float32, float32, float_status *status);
float32 float32_maxnum(float32, float32, float_status *status);
float32 float32_minnummag(float32, float32, float_status *status);
float32 float32_maxnummag(float32, float32, float_status *status);
float32 float32_minimum_number(float32, float32, float_status *status);
float32 float32_maximum_number(float32, float32, float_status *status);
bool float32_is_quiet_nan(float32, float_status *status);
bool float32_is_signaling_nan(float32, float_status *status);
float32 float32_silence_nan(float32, float_status *status);
@ -778,6 +784,8 @@ float64 float64_minnum(float64, float64, float_status *status);
float64 float64_maxnum(float64, float64, float_status *status);
float64 float64_minnummag(float64, float64, float_status *status);
float64 float64_maxnummag(float64, float64, float_status *status);
float64 float64_minimum_number(float64, float64, float_status *status);
float64 float64_maximum_number(float64, float64, float_status *status);
bool float64_is_quiet_nan(float64 a, float_status *status);
bool float64_is_signaling_nan(float64, float_status *status);
float64 float64_silence_nan(float64, float_status *status);
@ -1210,6 +1218,8 @@ float128 float128_minnum(float128, float128, float_status *status);
float128 float128_maxnum(float128, float128, float_status *status);
float128 float128_minnummag(float128, float128, float_status *status);
float128 float128_maxnummag(float128, float128, float_status *status);
float128 float128_minimum_number(float128, float128, float_status *status);
float128 float128_maximum_number(float128, float128, float_status *status);
bool float128_is_quiet_nan(float128, float_status *status);
bool float128_is_signaling_nan(float128, float_status *status);
float128 float128_silence_nan(float128, float_status *status);