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 <rth@twiddle.net>
---
CC: Aurelien Jarno <aurelien@aurel32.net>
fpu/softfloat-specialize.h | 14 ++++++++++++++
fpu/softfloat.c | 38 ++++++++++++++++++++++++++------------
include/fpu/softfloat.h | 9 +++++++--
3 files changed, 47 insertions(+), 14 deletions(-)
diff --git a/fpu/softfloat-specialize.h b/fpu/softfloat-specialize.h
index 46126e9e0a..9ccb59422c 100644
--- a/fpu/softfloat-specialize.h
+++ b/fpu/softfloat-specialize.h
@@ -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.
*----------------------------------------------------------------------------*/
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index fb4853682e..70a86e156c 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -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 );
@@ -4550,8 +4556,8 @@ int64_t floatx80_to_int64(floatx80 a, float_status *status)
if ( shiftCount ) {
float_raise(float_flag_invalid, status);
if ( ! aSign
- || ( ( aExp == 0x7FFF )
- && ( aSig != LIT64( 0x8000000000000000 ) ) )
+ || ((aExp == floatx80_infinity_high)
+ && (aSig != floatx80_infinity_low))
) {
return LIT64( 0x7FFFFFFFFFFFFFFF );
}
@@ -4858,7 +4864,9 @@ 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 +4941,8 @@ 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 +5047,8 @@ 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 +5059,8 @@ 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 +5114,8 @@ 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 +5131,8 @@ 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 +5955,8 @@ 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 );
diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
index 125dcb5586..7edf407cbc 100644
--- a/include/fpu/softfloat.h
+++ b/include/fpu/softfloat.h
@@ -563,6 +563,11 @@ 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.
*----------------------------------------------------------------------------*/
@@ -603,7 +608,8 @@ static inline floatx80 floatx80_chs(floatx80 a)
static inline int floatx80_is_infinity(floatx80 a)
{
- return (a.high & 0x7fff) == 0x7fff && a.low == 0x8000000000000000LL;
+ return (a.high & 0x7fff) == floatx80_infinity.high &&
+ a.low == floatx80_infinity.low;
}
static inline int floatx80_is_neg(floatx80 a)
@@ -646,7 +652,6 @@ 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
--
2.14.3
On 02/23/2018 06:59 AM, Laurent Vivier wrote:
> @@ -4550,8 +4556,8 @@ int64_t floatx80_to_int64(floatx80 a, float_status *status)
> if ( shiftCount ) {
> float_raise(float_flag_invalid, status);
> if ( ! aSign
> - || ( ( aExp == 0x7FFF )
> - && ( aSig != LIT64( 0x8000000000000000 ) ) )
> + || ((aExp == floatx80_infinity_high)
> + && (aSig != floatx80_infinity_low))
> ) {
As long as you're cleaning this up, m68k ignores the explicit integer bit when
considering an infinity. However, Intel doesn't ignore the bit -- it appears
to treat 7fff.0* as a NaN.
r~
Le 24/02/2018 à 03:26, Richard Henderson a écrit :
> On 02/23/2018 06:59 AM, Laurent Vivier wrote:
>> @@ -4550,8 +4556,8 @@ int64_t floatx80_to_int64(floatx80 a, float_status *status)
>> if ( shiftCount ) {
>> float_raise(float_flag_invalid, status);
>> if ( ! aSign
>> - || ( ( aExp == 0x7FFF )
>> - && ( aSig != LIT64( 0x8000000000000000 ) ) )
>> + || ((aExp == floatx80_infinity_high)
>> + && (aSig != floatx80_infinity_low))
>> ) {
>
> As long as you're cleaning this up, m68k ignores the explicit integer bit when
> considering an infinity. However, Intel doesn't ignore the bit -- it appears
> to treat 7fff.0* as a NaN.
According to the comment above the function:
"... If `a' is a NaN, the largest positive integer is returned.
Otherwise, if the conversion overflows, the largest integer with the
same sign as `a' is returned."
I think the change should be in fact:
@@ -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 );
Do you agree?
Thanks,
Laurent
On 02/24/2018 09:21 AM, Laurent Vivier wrote:
> I think the change should be in fact:
>
> @@ -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 );
>
> Do you agree?
Yep, looks good.
r~
Le 24/02/2018 à 18:26, Richard Henderson a écrit :
> On 02/24/2018 09:21 AM, Laurent Vivier wrote:
>> I think the change should be in fact:
>>
>> @@ -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 );
>>
>> Do you agree?
>
> Yep, looks good.
Thank you.
And according to your previous comment, floatx80_is_infinity() should
become:
static inline int floatx80_is_infinity(floatx80 a)
{
#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
}
Laurent
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