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softfloat: use floatx80_infinity in softfloat

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Since f3218a8 ("softfloat: add floatx80 constants")
floatx80_infinity is defined but never used.

This patch updates floatx80 functions to use
this definition.

This allows to define a different default Infinity
value on m68k: the m68k FPU defines infinity with
all bits set to zero in the mantissa.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20180224201802.911-4-laurent@vivier.eu>
This commit is contained in:
Laurent Vivier 2018-02-24 21:18:01 +01:00
parent 591596b77a
commit 0f605c889c
3 changed files with 50 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
fpu/softfloat-specialize.h
View File

@ -177,6 +177,20 @@ floatx80 floatx80_default_nan(float_status *status)
return r;
}
/*----------------------------------------------------------------------------
| The pattern for a default generated extended double-precision inf.
*----------------------------------------------------------------------------*/
#define floatx80_infinity_high 0x7FFF
#if defined(TARGET_M68K)
#define floatx80_infinity_low LIT64(0x0000000000000000)
#else
#define floatx80_infinity_low LIT64(0x8000000000000000)
#endif
const floatx80 floatx80_infinity
= make_floatx80_init(floatx80_infinity_high, floatx80_infinity_low);
/*----------------------------------------------------------------------------
| The pattern for a default generated quadruple-precision NaN.
*----------------------------------------------------------------------------*/

39
fpu/softfloat.c
View File

@ -2636,7 +2636,9 @@ floatx80 roundAndPackFloatx80(int8_t roundingPrecision, flag zSign,
) {
return packFloatx80( zSign, 0x7FFE, ~ roundMask );
}
return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
return packFloatx80(zSign,
floatx80_infinity_high,
floatx80_infinity_low);
}
if ( zExp <= 0 ) {
isTiny =
@ -3182,7 +3184,9 @@ floatx80 float32_to_floatx80(float32 a, float_status *status)
if (aSig) {
return commonNaNToFloatx80(float32ToCommonNaN(a, status), status);
}
return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
return packFloatx80(aSign,
floatx80_infinity_high,
floatx80_infinity_low);
}
if ( aExp == 0 ) {
if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 );
@ -4037,7 +4041,9 @@ floatx80 float64_to_floatx80(float64 a, float_status *status)
if (aSig) {
return commonNaNToFloatx80(float64ToCommonNaN(a, status), status);
}
return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
return packFloatx80(aSign,
floatx80_infinity_high,
floatx80_infinity_low);
}
if ( aExp == 0 ) {
if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 );
@ -4549,10 +4555,7 @@ int64_t floatx80_to_int64(floatx80 a, float_status *status)
if ( shiftCount <= 0 ) {
if ( shiftCount ) {
float_raise(float_flag_invalid, status);
if ( ! aSign
|| ( ( aExp == 0x7FFF )
&& ( aSig != LIT64( 0x8000000000000000 ) ) )
) {
if (!aSign || floatx80_is_any_nan(a)) {
return LIT64( 0x7FFFFFFFFFFFFFFF );
}
return (int64_t) LIT64( 0x8000000000000000 );
@ -4858,7 +4861,9 @@ static floatx80 addFloatx80Sigs(floatx80 a, floatx80 b, flag zSign,
if ((uint64_t)(bSig << 1)) {
return propagateFloatx80NaN(a, b, status);
}
return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
return packFloatx80(zSign,
floatx80_infinity_high,
floatx80_infinity_low);
}
if ( aExp == 0 ) ++expDiff;
shift64ExtraRightJamming( aSig, 0, - expDiff, &aSig, &zSig1 );
@ -4933,7 +4938,8 @@ static floatx80 subFloatx80Sigs(floatx80 a, floatx80 b, flag zSign,
if ((uint64_t)(bSig << 1)) {
return propagateFloatx80NaN(a, b, status);
}
return packFloatx80( zSign ^ 1, 0x7FFF, LIT64( 0x8000000000000000 ) );
return packFloatx80(zSign ^ 1, floatx80_infinity_high,
floatx80_infinity_low);
}
if ( aExp == 0 ) ++expDiff;
shift128RightJamming( aSig, 0, - expDiff, &aSig, &zSig1 );
@ -5038,7 +5044,8 @@ floatx80 floatx80_mul(floatx80 a, floatx80 b, float_status *status)
return propagateFloatx80NaN(a, b, status);
}
if ( ( bExp | bSig ) == 0 ) goto invalid;
return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
return packFloatx80(zSign, floatx80_infinity_high,
floatx80_infinity_low);
}
if ( bExp == 0x7FFF ) {
if ((uint64_t)(bSig << 1)) {
@ -5049,7 +5056,8 @@ floatx80 floatx80_mul(floatx80 a, floatx80 b, float_status *status)
float_raise(float_flag_invalid, status);
return floatx80_default_nan(status);
}
return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
return packFloatx80(zSign, floatx80_infinity_high,
floatx80_infinity_low);
}
if ( aExp == 0 ) {
if ( aSig == 0 ) return packFloatx80( zSign, 0, 0 );
@ -5103,7 +5111,8 @@ floatx80 floatx80_div(floatx80 a, floatx80 b, float_status *status)
}
goto invalid;
}
return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
return packFloatx80(zSign, floatx80_infinity_high,
floatx80_infinity_low);
}
if ( bExp == 0x7FFF ) {
if ((uint64_t)(bSig << 1)) {
@ -5119,7 +5128,8 @@ floatx80 floatx80_div(floatx80 a, floatx80 b, float_status *status)
return floatx80_default_nan(status);
}
float_raise(float_flag_divbyzero, status);
return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
return packFloatx80(zSign, floatx80_infinity_high,
floatx80_infinity_low);
}
normalizeFloatx80Subnormal( bSig, &bExp, &bSig );
}
@ -5942,7 +5952,8 @@ floatx80 float128_to_floatx80(float128 a, float_status *status)
if ( aSig0 | aSig1 ) {
return commonNaNToFloatx80(float128ToCommonNaN(a, status), status);
}
return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) );
return packFloatx80(aSign, floatx80_infinity_high,
floatx80_infinity_low);
}
if ( aExp == 0 ) {
if ( ( aSig0 | aSig1 ) == 0 ) return packFloatx80( aSign, 0, 0 );

13
include/fpu/softfloat.h
View File

@ -572,6 +572,11 @@ float32 floatx80_to_float32(floatx80, float_status *status);
float64 floatx80_to_float64(floatx80, float_status *status);
float128 floatx80_to_float128(floatx80, float_status *status);
/*----------------------------------------------------------------------------
| The pattern for an extended double-precision inf.
*----------------------------------------------------------------------------*/
extern const floatx80 floatx80_infinity;
/*----------------------------------------------------------------------------
| Software IEC/IEEE extended double-precision operations.
*----------------------------------------------------------------------------*/
@ -612,7 +617,12 @@ static inline floatx80 floatx80_chs(floatx80 a)
static inline int floatx80_is_infinity(floatx80 a)
{
return (a.high & 0x7fff) == 0x7fff && a.low == 0x8000000000000000LL;
#if defined(TARGET_M68K)
return (a.high & 0x7fff) == floatx80_infinity.high && !(a.low << 1);
#else
return (a.high & 0x7fff) == floatx80_infinity.high &&
a.low == floatx80_infinity.low;
#endif
}
static inline int floatx80_is_neg(floatx80 a)
@ -655,7 +665,6 @@ static inline bool floatx80_invalid_encoding(floatx80 a)
#define floatx80_ln2 make_floatx80(0x3ffe, 0xb17217f7d1cf79acLL)
#define floatx80_pi make_floatx80(0x4000, 0xc90fdaa22168c235LL)
#define floatx80_half make_floatx80(0x3ffe, 0x8000000000000000LL)
#define floatx80_infinity make_floatx80(0x7fff, 0x8000000000000000LL)
/*----------------------------------------------------------------------------
| Returns the fraction bits of the extended double-precision floating-point