QEMU currently implements IEEE 754-2008 minNum/maxNum. This patch adds support for IEEE 754-201x minimumNumber/maximumNumber which is required by the RISC-V port.
minNum(x, y) is defined as - min(x, y) if neither is NaN - if one of x and y is a number and one is qNaN, return the number - if both are qNaN, or either is sNaN, return NaN minimumNumber(x, y) is defined as - min(x, y) if neither is NaN - if one of x and y is a number and one is qNaN or sNaN, return the number - if both are NaN, return the number Both functions signal the invalid exception on sNaN inputs. Signed-off-by: Michael Clark <m...@sifive.com> --- fpu/softfloat.c | 41 +++++++++++++++++++++++++++++++++++------ include/fpu/softfloat.h | 4 ++++ 2 files changed, 39 insertions(+), 6 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 433c5da..5793cc9 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -7675,6 +7675,9 @@ int float128_compare_quiet(float128 a, float128 b, float_status *status) * minnummag() and maxnummag() functions correspond to minNumMag() * and minNumMag() from the IEEE-754 2008. */ + +enum { ieee2008 = 1, ieee201x = 2 }; + #define MINMAX(s) \ static inline float ## s float ## s ## _minmax(float ## s a, float ## s b, \ int ismin, int isieee, \ @@ -7687,12 +7690,26 @@ static inline float ## s float ## s ## _minmax(float ## s a, float ## s b, \ b = float ## s ## _squash_input_denormal(b, status); \ if (float ## s ## _is_any_nan(a) || \ float ## s ## _is_any_nan(b)) { \ - if (isieee) { \ + if (isieee == ieee2008) { \ if (float ## s ## _is_quiet_nan(a, status) && \ !float ## s ##_is_any_nan(b)) { \ return b; \ } else if (float ## s ## _is_quiet_nan(b, status) && \ - !float ## s ## _is_any_nan(a)) { \ + !float ## s ## _is_any_nan(a)) { \ + return a; \ + } \ + } else if (isieee == ieee201x) { \ + if (float ## s ## _is_any_nan(a) && \ + !float ## s ##_is_any_nan(b)) { \ + if (!float ## s ## _is_quiet_nan(a, status)) { \ + float_raise(float_flag_invalid, status); \ + } \ + return b; \ + } else if (float ## s ## _is_any_nan(b) && \ + !float ## s ## _is_any_nan(a)) { \ + if (!float ## s ## _is_quiet_nan(b, status)) { \ + float_raise(float_flag_invalid, status); \ + } \ return a; \ } \ } \ @@ -7743,25 +7760,37 @@ float ## s float ## s ## _max(float ## s a, float ## s b, \ float ## s float ## s ## _minnum(float ## s a, float ## s b, \ float_status *status) \ { \ - return float ## s ## _minmax(a, b, 1, 1, 0, status); \ + return float ## s ## _minmax(a, b, 1, ieee2008, 0, status); \ } \ \ float ## s float ## s ## _maxnum(float ## s a, float ## s b, \ float_status *status) \ { \ - return float ## s ## _minmax(a, b, 0, 1, 0, status); \ + return float ## s ## _minmax(a, b, 0, ieee2008, 0, status); \ +} \ + \ +float ## s float ## s ## _minimumnumber(float ## s a, float ## s b, \ + float_status *status) \ +{ \ + return float ## s ## _minmax(a, b, 1, ieee201x, 0, status); \ +} \ + \ +float ## s float ## s ## _maximumnumber(float ## s a, float ## s b, \ + float_status *status) \ +{ \ + return float ## s ## _minmax(a, b, 0, ieee201x, 0, status); \ } \ \ float ## s float ## s ## _minnummag(float ## s a, float ## s b, \ float_status *status) \ { \ - return float ## s ## _minmax(a, b, 1, 1, 1, status); \ + return float ## s ## _minmax(a, b, 1, ieee2008, 1, status); \ } \ \ float ## s float ## s ## _maxnummag(float ## s a, float ## s b, \ float_status *status) \ { \ - return float ## s ## _minmax(a, b, 0, 1, 1, status); \ + return float ## s ## _minmax(a, b, 0, ieee2008, 1, status); \ } MINMAX(32) diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h index 0f96a0e..e0d0259 100644 --- a/include/fpu/softfloat.h +++ b/include/fpu/softfloat.h @@ -424,6 +424,8 @@ float32 float32_min(float32, float32, float_status *status); float32 float32_max(float32, float32, float_status *status); float32 float32_minnum(float32, float32, float_status *status); float32 float32_maxnum(float32, float32, float_status *status); +float32 float32_minimumnumber(float32, float32, float_status *status); +float32 float32_maximumnumber(float32, float32, float_status *status); float32 float32_minnummag(float32, float32, float_status *status); float32 float32_maxnummag(float32, float32, float_status *status); int float32_is_quiet_nan(float32, float_status *status); @@ -536,6 +538,8 @@ float64 float64_min(float64, float64, float_status *status); float64 float64_max(float64, float64, float_status *status); float64 float64_minnum(float64, float64, float_status *status); float64 float64_maxnum(float64, float64, float_status *status); +float64 float64_minimumnumber(float64, float64, float_status *status); +float64 float64_maximumnumber(float64, float64, float_status *status); float64 float64_minnummag(float64, float64, float_status *status); float64 float64_maxnummag(float64, float64, float_status *status); int float64_is_quiet_nan(float64 a, float_status *status); -- 2.7.0