From f5a64251f2db2271970a1f4b7f8176d4de4dec91 Mon Sep 17 00:00:00 2001 From: Aurelien Jarno Date: Thu, 14 Apr 2011 00:49:30 +0200 Subject: [PATCH] softfloat: improve description of comparison functions Make clear for all comparison functions which ones trigger an exception for all NaNs, and which one only for sNaNs. Reviewed-by: Peter Maydell Signed-off-by: Aurelien Jarno --- fpu/softfloat.c | 85 ++++++++++++++++++++++++++++++++------------------------- 1 file changed, 48 insertions(+), 37 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index efd718b..6ce0b61 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -2338,9 +2338,9 @@ int float32_eq( float32 a, float32 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the single-precision floating-point value `a' is less than -| or equal to the corresponding value `b', and 0 otherwise. The comparison -| is performed according to the IEC/IEEE Standard for Binary Floating-Point -| Arithmetic. +| or equal to the corresponding value `b', and 0 otherwise. The invalid +| exception is raised if either operand is a NaN. The comparison is performed +| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float32_le( float32 a, float32 b STATUS_PARAM ) @@ -2367,8 +2367,9 @@ int float32_le( float32 a, float32 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the single-precision floating-point value `a' is less than -| the corresponding value `b', and 0 otherwise. The comparison is performed -| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| the corresponding value `b', and 0 otherwise. The invalid exception is +| raised if either operand is a NaN. The comparison is performed according +| to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float32_lt( float32 a, float32 b STATUS_PARAM ) @@ -2395,8 +2396,9 @@ int float32_lt( float32 a, float32 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the single-precision floating-point values `a' and `b' cannot -| be compared, and 0 otherwise. The comparison is performed according to the -| IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| be compared, and 0 otherwise. The invalid exception is raised if either +| operand is a NaN. The comparison is performed according to the IEC/IEEE +| Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float32_unordered( float32 a, float32 b STATUS_PARAM ) @@ -2415,8 +2417,9 @@ int float32_unordered( float32 a, float32 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the single-precision floating-point value `a' is equal to -| the corresponding value `b', and 0 otherwise. The comparison is performed -| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an +| exception. The comparison is performed according to the IEC/IEEE Standard +| for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float32_eq_quiet( float32 a, float32 b STATUS_PARAM ) @@ -3602,9 +3605,9 @@ int float64_eq( float64 a, float64 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the double-precision floating-point value `a' is less than or -| equal to the corresponding value `b', and 0 otherwise. The comparison is -| performed according to the IEC/IEEE Standard for Binary Floating-Point -| Arithmetic. +| equal to the corresponding value `b', and 0 otherwise. The invalid +| exception is raised if either operand is a NaN. The comparison is performed +| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float64_le( float64 a, float64 b STATUS_PARAM ) @@ -3631,8 +3634,9 @@ int float64_le( float64 a, float64 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the double-precision floating-point value `a' is less than -| the corresponding value `b', and 0 otherwise. The comparison is performed -| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| the corresponding value `b', and 0 otherwise. The invalid exception is +| raised if either operand is a NaN. The comparison is performed according +| to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float64_lt( float64 a, float64 b STATUS_PARAM ) @@ -3659,8 +3663,9 @@ int float64_lt( float64 a, float64 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the double-precision floating-point values `a' and `b' cannot -| be compared, and 0 otherwise. The comparison is performed according to the -| IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| be compared, and 0 otherwise. The invalid exception is raised if either +| operand is a NaN. The comparison is performed according to the IEC/IEEE +| Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float64_unordered( float64 a, float64 b STATUS_PARAM ) @@ -3679,8 +3684,9 @@ int float64_unordered( float64 a, float64 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the double-precision floating-point value `a' is equal to the -| corresponding value `b', and 0 otherwise. The comparison is performed -| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an +| exception.The comparison is performed according to the IEC/IEEE Standard +| for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float64_eq_quiet( float64 a, float64 b STATUS_PARAM ) @@ -4614,8 +4620,9 @@ int floatx80_eq( floatx80 a, floatx80 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the extended double-precision floating-point value `a' is | less than or equal to the corresponding value `b', and 0 otherwise. The -| comparison is performed according to the IEC/IEEE Standard for Binary -| Floating-Point Arithmetic. +| invalid exception is raised if either operand is a NaN. The comparison is +| performed according to the IEC/IEEE Standard for Binary Floating-Point +| Arithmetic. *----------------------------------------------------------------------------*/ int floatx80_le( floatx80 a, floatx80 b STATUS_PARAM ) @@ -4646,9 +4653,9 @@ int floatx80_le( floatx80 a, floatx80 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the extended double-precision floating-point value `a' is -| less than the corresponding value `b', and 0 otherwise. The comparison -| is performed according to the IEC/IEEE Standard for Binary Floating-Point -| Arithmetic. +| less than the corresponding value `b', and 0 otherwise. The invalid +| exception is raised if either operand is a NaN. The comparison is performed +| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int floatx80_lt( floatx80 a, floatx80 b STATUS_PARAM ) @@ -4679,8 +4686,9 @@ int floatx80_lt( floatx80 a, floatx80 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the extended double-precision floating-point values `a' and `b' -| cannot be compared, and 0 otherwise. The comparison is performed according -| to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| cannot be compared, and 0 otherwise. The invalid exception is raised if +| either operand is a NaN. The comparison is performed according to the +| IEC/IEEE Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int floatx80_unordered( floatx80 a, floatx80 b STATUS_PARAM ) { @@ -4697,9 +4705,9 @@ int floatx80_unordered( floatx80 a, floatx80 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the extended double-precision floating-point value `a' is -| equal to the corresponding value `b', and 0 otherwise. The comparison is -| performed according to the IEC/IEEE Standard for Binary Floating-Point -| Arithmetic. +| equal to the corresponding value `b', and 0 otherwise. Quiet NaNs do not +| cause an exception. The comparison is performed according to the IEC/IEEE +| Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int floatx80_eq_quiet( floatx80 a, floatx80 b STATUS_PARAM ) @@ -5776,9 +5784,9 @@ int float128_eq( float128 a, float128 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the quadruple-precision floating-point value `a' is less than -| or equal to the corresponding value `b', and 0 otherwise. The comparison -| is performed according to the IEC/IEEE Standard for Binary Floating-Point -| Arithmetic. +| or equal to the corresponding value `b', and 0 otherwise. The invalid +| exception is raised if either operand is a NaN. The comparison is performed +| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float128_le( float128 a, float128 b STATUS_PARAM ) @@ -5809,8 +5817,9 @@ int float128_le( float128 a, float128 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the quadruple-precision floating-point value `a' is less than -| the corresponding value `b', and 0 otherwise. The comparison is performed -| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| the corresponding value `b', and 0 otherwise. The invalid exception is +| raised if either operand is a NaN. The comparison is performed according +| to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float128_lt( float128 a, float128 b STATUS_PARAM ) @@ -5841,8 +5850,9 @@ int float128_lt( float128 a, float128 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the quadruple-precision floating-point values `a' and `b' cannot -| be compared, and 0 otherwise. The comparison is performed according to the -| IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| be compared, and 0 otherwise. The invalid exception is raised if either +| operand is a NaN. The comparison is performed according to the IEC/IEEE +| Standard for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float128_unordered( float128 a, float128 b STATUS_PARAM ) @@ -5860,8 +5870,9 @@ int float128_unordered( float128 a, float128 b STATUS_PARAM ) /*---------------------------------------------------------------------------- | Returns 1 if the quadruple-precision floating-point value `a' is equal to -| the corresponding value `b', and 0 otherwise. The comparison is performed -| according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. +| the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an +| exception. The comparison is performed according to the IEC/IEEE Standard +| for Binary Floating-Point Arithmetic. *----------------------------------------------------------------------------*/ int float128_eq_quiet( float128 a, float128 b STATUS_PARAM ) -- 2.7.4