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authorDavid 'Digit' Turner <digit@google.com>2009-09-14 14:32:27 -0700
committerDavid 'Digit' Turner <digit@google.com>2009-09-14 14:32:27 -0700
commit5d8f37ad78fc66901af50c762029a501561f3b23 (patch)
tree206790f8f21000850a98c4f9590a79e779106278 /fpu/softfloat.c
parentcd059b15f2c7df69f4a087bd66900eb172e41d1c (diff)
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Merge upstream QEMU 10.0.50 into the Android source tree.
This change integrates many changes from the upstream QEMU sources. Its main purpose is to enable correct ARMv6 and ARMv7 support to the Android emulator. Due to the nature of the upstream code base, this unfortunately also required changes to many other parts of the source. Note that to ensure easier integrations in the future, some source files and directories that have heavy Android-specific customization have been renamed with an -android suffix. The original files are still there for easier integration tracking, but *never* compiled. For example: net.c net-android.c qemu-char.c qemu-char-android.c slirp/ slirp-android/ etc... Tested on linux-x86, darwin-x86 and windows host machines.
Diffstat (limited to 'fpu/softfloat.c')
-rw-r--r--fpu/softfloat.c153
1 files changed, 141 insertions, 12 deletions
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index 3ec1e0d..4d58744 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -30,6 +30,8 @@ these four paragraphs for those parts of this code that are retained.
=============================================================================*/
+/* FIXME: Flush-To-Zero only effects results. Denormal inputs should also
+ be flushed to zero. */
#include "softfloat.h"
/*----------------------------------------------------------------------------
@@ -294,6 +296,7 @@ static float32 roundAndPackFloat32( flag zSign, int16 zExp, bits32 zSig STATUS_P
return packFloat32( zSign, 0xFF, - ( roundIncrement == 0 ));
}
if ( zExp < 0 ) {
+ if ( STATUS(flush_to_zero) ) return packFloat32( zSign, 0, 0 );
isTiny =
( STATUS(float_detect_tininess) == float_tininess_before_rounding )
|| ( zExp < -1 )
@@ -457,6 +460,7 @@ static float64 roundAndPackFloat64( flag zSign, int16 zExp, bits64 zSig STATUS_P
return packFloat64( zSign, 0x7FF, - ( roundIncrement == 0 ));
}
if ( zExp < 0 ) {
+ if ( STATUS(flush_to_zero) ) return packFloat64( zSign, 0, 0 );
isTiny =
( STATUS(float_detect_tininess) == float_tininess_before_rounding )
|| ( zExp < -1 )
@@ -635,6 +639,7 @@ static floatx80
goto overflow;
}
if ( zExp <= 0 ) {
+ if ( STATUS(flush_to_zero) ) return packFloatx80( zSign, 0, 0 );
isTiny =
( STATUS(float_detect_tininess) == float_tininess_before_rounding )
|| ( zExp < 0 )
@@ -965,6 +970,7 @@ static float128
return packFloat128( zSign, 0x7FFF, 0, 0 );
}
if ( zExp < 0 ) {
+ if ( STATUS(flush_to_zero) ) return packFloat128( zSign, 0, 0, 0 );
isTiny =
( STATUS(float_detect_tininess) == float_tininess_before_rounding )
|| ( zExp < -1 )
@@ -1637,7 +1643,10 @@ static float32 addFloat32Sigs( float32 a, float32 b, flag zSign STATUS_PARAM)
if ( aSig | bSig ) return propagateFloat32NaN( a, b STATUS_VAR );
return a;
}
- if ( aExp == 0 ) return packFloat32( zSign, 0, ( aSig + bSig )>>6 );
+ if ( aExp == 0 ) {
+ if ( STATUS(flush_to_zero) ) return packFloat32( zSign, 0, 0 );
+ return packFloat32( zSign, 0, ( aSig + bSig )>>6 );
+ }
zSig = 0x40000000 + aSig + bSig;
zExp = aExp;
goto roundAndPack;
@@ -2048,6 +2057,53 @@ float32 float32_sqrt( float32 a STATUS_PARAM )
}
/*----------------------------------------------------------------------------
+| Returns the binary log of the single-precision floating-point value `a'.
+| The operation is performed according to the IEC/IEEE Standard for Binary
+| Floating-Point Arithmetic.
+*----------------------------------------------------------------------------*/
+float32 float32_log2( float32 a STATUS_PARAM )
+{
+ flag aSign, zSign;
+ int16 aExp;
+ bits32 aSig, zSig, i;
+
+ aSig = extractFloat32Frac( a );
+ aExp = extractFloat32Exp( a );
+ aSign = extractFloat32Sign( a );
+
+ if ( aExp == 0 ) {
+ if ( aSig == 0 ) return packFloat32( 1, 0xFF, 0 );
+ normalizeFloat32Subnormal( aSig, &aExp, &aSig );
+ }
+ if ( aSign ) {
+ float_raise( float_flag_invalid STATUS_VAR);
+ return float32_default_nan;
+ }
+ if ( aExp == 0xFF ) {
+ if ( aSig ) return propagateFloat32NaN( a, float32_zero STATUS_VAR );
+ return a;
+ }
+
+ aExp -= 0x7F;
+ aSig |= 0x00800000;
+ zSign = aExp < 0;
+ zSig = aExp << 23;
+
+ for (i = 1 << 22; i > 0; i >>= 1) {
+ aSig = ( (bits64)aSig * aSig ) >> 23;
+ if ( aSig & 0x01000000 ) {
+ aSig >>= 1;
+ zSig |= i;
+ }
+ }
+
+ if ( zSign )
+ zSig = -zSig;
+
+ return normalizeRoundAndPackFloat32( zSign, 0x85, zSig STATUS_VAR );
+}
+
+/*----------------------------------------------------------------------------
| 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.
@@ -2595,7 +2651,10 @@ static float64 addFloat64Sigs( float64 a, float64 b, flag zSign STATUS_PARAM )
if ( aSig | bSig ) return propagateFloat64NaN( a, b STATUS_VAR );
return a;
}
- if ( aExp == 0 ) return packFloat64( zSign, 0, ( aSig + bSig )>>9 );
+ if ( aExp == 0 ) {
+ if ( STATUS(flush_to_zero) ) return packFloat64( zSign, 0, 0 );
+ return packFloat64( zSign, 0, ( aSig + bSig )>>9 );
+ }
zSig = LIT64( 0x4000000000000000 ) + aSig + bSig;
zExp = aExp;
goto roundAndPack;
@@ -2994,6 +3053,52 @@ float64 float64_sqrt( float64 a STATUS_PARAM )
}
/*----------------------------------------------------------------------------
+| Returns the binary log of the double-precision floating-point value `a'.
+| The operation is performed according to the IEC/IEEE Standard for Binary
+| Floating-Point Arithmetic.
+*----------------------------------------------------------------------------*/
+float64 float64_log2( float64 a STATUS_PARAM )
+{
+ flag aSign, zSign;
+ int16 aExp;
+ bits64 aSig, aSig0, aSig1, zSig, i;
+
+ aSig = extractFloat64Frac( a );
+ aExp = extractFloat64Exp( a );
+ aSign = extractFloat64Sign( a );
+
+ if ( aExp == 0 ) {
+ if ( aSig == 0 ) return packFloat64( 1, 0x7FF, 0 );
+ normalizeFloat64Subnormal( aSig, &aExp, &aSig );
+ }
+ if ( aSign ) {
+ float_raise( float_flag_invalid STATUS_VAR);
+ return float64_default_nan;
+ }
+ if ( aExp == 0x7FF ) {
+ if ( aSig ) return propagateFloat64NaN( a, float64_zero STATUS_VAR );
+ return a;
+ }
+
+ aExp -= 0x3FF;
+ aSig |= LIT64( 0x0010000000000000 );
+ zSign = aExp < 0;
+ zSig = (bits64)aExp << 52;
+ for (i = 1LL << 51; i > 0; i >>= 1) {
+ mul64To128( aSig, aSig, &aSig0, &aSig1 );
+ aSig = ( aSig0 << 12 ) | ( aSig1 >> 52 );
+ if ( aSig & LIT64( 0x0020000000000000 ) ) {
+ aSig >>= 1;
+ zSig |= i;
+ }
+ }
+
+ if ( zSign )
+ zSig = -zSig;
+ return normalizeRoundAndPackFloat64( zSign, 0x408, zSig STATUS_VAR );
+}
+
+/*----------------------------------------------------------------------------
| 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.
@@ -4597,7 +4702,10 @@ static float128 addFloat128Sigs( float128 a, float128 b, flag zSign STATUS_PARAM
return a;
}
add128( aSig0, aSig1, bSig0, bSig1, &zSig0, &zSig1 );
- if ( aExp == 0 ) return packFloat128( zSign, 0, zSig0, zSig1 );
+ if ( aExp == 0 ) {
+ if ( STATUS(flush_to_zero) ) return packFloat128( zSign, 0, 0, 0 );
+ return packFloat128( zSign, 0, zSig0, zSig1 );
+ }
zSig2 = 0;
zSig0 |= LIT64( 0x0002000000000000 );
zExp = aExp;
@@ -4987,7 +5095,7 @@ float128 float128_rem( float128 a, float128 b STATUS_PARAM )
sub128( aSig0, aSig1, bSig0, bSig1, &aSig0, &aSig1 );
} while ( 0 <= (sbits64) aSig0 );
add128(
- aSig0, aSig1, alternateASig0, alternateASig1, &sigMean0, &sigMean1 );
+ aSig0, aSig1, alternateASig0, alternateASig1, (bits64 *)&sigMean0, &sigMean1 );
if ( ( sigMean0 < 0 )
|| ( ( ( sigMean0 | sigMean1 ) == 0 ) && ( q & 1 ) ) ) {
aSig0 = alternateASig0;
@@ -5479,8 +5587,14 @@ float32 float32_scalbn( float32 a, int n STATUS_PARAM )
if ( aExp == 0xFF ) {
return a;
}
- aExp += n;
- return roundAndPackFloat32( aSign, aExp, aSig STATUS_VAR );
+ if ( aExp != 0 )
+ aSig |= 0x00800000;
+ else if ( aSig == 0 )
+ return a;
+
+ aExp += n - 1;
+ aSig <<= 7;
+ return normalizeRoundAndPackFloat32( aSign, aExp, aSig STATUS_VAR );
}
float64 float64_scalbn( float64 a, int n STATUS_PARAM )
@@ -5496,8 +5610,14 @@ float64 float64_scalbn( float64 a, int n STATUS_PARAM )
if ( aExp == 0x7FF ) {
return a;
}
- aExp += n;
- return roundAndPackFloat64( aSign, aExp, aSig STATUS_VAR );
+ if ( aExp != 0 )
+ aSig |= LIT64( 0x0010000000000000 );
+ else if ( aSig == 0 )
+ return a;
+
+ aExp += n - 1;
+ aSig <<= 10;
+ return normalizeRoundAndPackFloat64( aSign, aExp, aSig STATUS_VAR );
}
#ifdef FLOATX80
@@ -5514,9 +5634,12 @@ floatx80 floatx80_scalbn( floatx80 a, int n STATUS_PARAM )
if ( aExp == 0x7FF ) {
return a;
}
+ if (aExp == 0 && aSig == 0)
+ return a;
+
aExp += n;
- return roundAndPackFloatx80( STATUS(floatx80_rounding_precision),
- aSign, aExp, aSig, 0 STATUS_VAR );
+ return normalizeRoundAndPackFloatx80( STATUS(floatx80_rounding_precision),
+ aSign, aExp, aSig, 0 STATUS_VAR );
}
#endif
@@ -5534,8 +5657,14 @@ float128 float128_scalbn( float128 a, int n STATUS_PARAM )
if ( aExp == 0x7FFF ) {
return a;
}
- aExp += n;
- return roundAndPackFloat128( aSign, aExp, aSig0, aSig1, 0 STATUS_VAR );
+ if ( aExp != 0 )
+ aSig0 |= LIT64( 0x0001000000000000 );
+ else if ( aSig0 == 0 && aSig1 == 0 )
+ return a;
+
+ aExp += n - 1;
+ return normalizeRoundAndPackFloat128( aSign, aExp, aSig0, aSig1
+ STATUS_VAR );
}
#endif