Add floatnn_minnum() and floatnn_maxnum() functions which are equivalent to the minNum() and maxNum() functions from IEEE 754-2008. They are similar to min() and max() but differ in the handling of QNaN arguments.
Signed-off-by: Will Newton <will.new...@linaro.org> --- fpu/softfloat.c | 32 +++++++++++++++++++++++++++++--- include/fpu/softfloat.h | 4 ++++ 2 files changed, 33 insertions(+), 3 deletions(-) Changes in v8: - Use existing MINMAX macro to implement minnum and maxnum - Improve comment diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 97bf627..dbda61b 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -6705,10 +6705,17 @@ int float128_compare_quiet( float128 a, float128 b STATUS_PARAM ) /* min() and max() functions. These can't be implemented as * 'compare and pick one input' because that would mishandle * NaNs and +0 vs -0. + * + * minnum() and maxnum() functions. These are similar to the min() + * and max() functions but if one of the arguments is a QNaN and + * the other is numerical then the numerical argument is returned. + * minnum() and maxnum correspond to the IEEE 754-2008 minNum() + * and maxNum() operations. min() and max() are the typical min/max + * semantics provided by many CPUs which predate that specification. */ #define MINMAX(s) \ INLINE float ## s float ## s ## _minmax(float ## s a, float ## s b, \ - int ismin STATUS_PARAM ) \ + int ismin, int isieee STATUS_PARAM) \ { \ flag aSign, bSign; \ uint ## s ## _t av, bv; \ @@ -6716,6 +6723,15 @@ INLINE float ## s float ## s ## _minmax(float ## s a, float ## s b, \ b = float ## s ## _squash_input_denormal(b STATUS_VAR); \ if (float ## s ## _is_any_nan(a) || \ float ## s ## _is_any_nan(b)) { \ + if (isieee) { \ + if (float ## s ## _is_quiet_nan(a) && \ + !float ## s ##_is_any_nan(b)) { \ + return b; \ + } else if (float ## s ## _is_quiet_nan(b) && \ + !float ## s ## _is_any_nan(a)) { \ + return a; \ + } \ + } \ return propagateFloat ## s ## NaN(a, b STATUS_VAR); \ } \ aSign = extractFloat ## s ## Sign(a); \ @@ -6739,12 +6755,22 @@ INLINE float ## s float ## s ## _minmax(float ## s a, float ## s b, \ \ float ## s float ## s ## _min(float ## s a, float ## s b STATUS_PARAM) \ { \ - return float ## s ## _minmax(a, b, 1 STATUS_VAR); \ + return float ## s ## _minmax(a, b, 1, 0 STATUS_VAR); \ } \ \ float ## s float ## s ## _max(float ## s a, float ## s b STATUS_PARAM) \ { \ - return float ## s ## _minmax(a, b, 0 STATUS_VAR); \ + return float ## s ## _minmax(a, b, 0, 0 STATUS_VAR); \ +} \ + \ +float ## s float ## s ## _minnum(float ## s a, float ## s b STATUS_PARAM) \ +{ \ + return float ## s ## _minmax(a, b, 1, 1 STATUS_VAR); \ +} \ + \ +float ## s float ## s ## _maxnum(float ## s a, float ## s b STATUS_PARAM) \ +{ \ + return float ## s ## _minmax(a, b, 0, 1 STATUS_VAR); \ } MINMAX(32) diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h index f3927e2..2365274 100644 --- a/include/fpu/softfloat.h +++ b/include/fpu/softfloat.h @@ -302,6 +302,8 @@ int float32_compare( float32, float32 STATUS_PARAM ); int float32_compare_quiet( float32, float32 STATUS_PARAM ); float32 float32_min(float32, float32 STATUS_PARAM); float32 float32_max(float32, float32 STATUS_PARAM); +float32 float32_minnum(float32, float32 STATUS_PARAM); +float32 float32_maxnum(float32, float32 STATUS_PARAM); int float32_is_quiet_nan( float32 ); int float32_is_signaling_nan( float32 ); float32 float32_maybe_silence_nan( float32 ); @@ -408,6 +410,8 @@ int float64_compare( float64, float64 STATUS_PARAM ); int float64_compare_quiet( float64, float64 STATUS_PARAM ); float64 float64_min(float64, float64 STATUS_PARAM); float64 float64_max(float64, float64 STATUS_PARAM); +float64 float64_minnum(float64, float64 STATUS_PARAM); +float64 float64_maxnum(float64, float64 STATUS_PARAM); int float64_is_quiet_nan( float64 a ); int float64_is_signaling_nan( float64 ); float64 float64_maybe_silence_nan( float64 ); -- 1.8.1.4