+/*
+ * QEMU float support
+ *
+ * Derived from SoftFloat.
+ */
/*============================================================================
=============================================================================*/
+#if defined(TARGET_MIPS) || defined(TARGET_SH4) || defined(TARGET_UNICORE32)
+#define SNAN_BIT_IS_ONE 1
+#else
+#define SNAN_BIT_IS_ONE 0
+#endif
+
+/*----------------------------------------------------------------------------
+| The pattern for a default generated half-precision NaN.
+*----------------------------------------------------------------------------*/
+#if defined(TARGET_ARM)
+const float16 float16_default_nan = const_float16(0x7E00);
+#elif SNAN_BIT_IS_ONE
+const float16 float16_default_nan = const_float16(0x7DFF);
+#else
+const float16 float16_default_nan = const_float16(0xFE00);
+#endif
+
+/*----------------------------------------------------------------------------
+| The pattern for a default generated single-precision NaN.
+*----------------------------------------------------------------------------*/
+#if defined(TARGET_SPARC)
+const float32 float32_default_nan = const_float32(0x7FFFFFFF);
+#elif defined(TARGET_PPC) || defined(TARGET_ARM) || defined(TARGET_ALPHA)
+const float32 float32_default_nan = const_float32(0x7FC00000);
+#elif SNAN_BIT_IS_ONE
+const float32 float32_default_nan = const_float32(0x7FBFFFFF);
+#else
+const float32 float32_default_nan = const_float32(0xFFC00000);
+#endif
+
/*----------------------------------------------------------------------------
-| Underflow tininess-detection mode, statically initialized to default value.
-| (The declaration in `softfloat.h' must match the `int8' type here.)
+| The pattern for a default generated double-precision NaN.
*----------------------------------------------------------------------------*/
-int8 float_detect_tininess = float_tininess_after_rounding;
+#if defined(TARGET_SPARC)
+const float64 float64_default_nan = const_float64(LIT64( 0x7FFFFFFFFFFFFFFF ));
+#elif defined(TARGET_PPC) || defined(TARGET_ARM) || defined(TARGET_ALPHA)
+const float64 float64_default_nan = const_float64(LIT64( 0x7FF8000000000000 ));
+#elif SNAN_BIT_IS_ONE
+const float64 float64_default_nan = const_float64(LIT64( 0x7FF7FFFFFFFFFFFF ));
+#else
+const float64 float64_default_nan = const_float64(LIT64( 0xFFF8000000000000 ));
+#endif
+
+/*----------------------------------------------------------------------------
+| The pattern for a default generated extended double-precision NaN.
+*----------------------------------------------------------------------------*/
+#if SNAN_BIT_IS_ONE
+#define floatx80_default_nan_high 0x7FFF
+#define floatx80_default_nan_low LIT64( 0xBFFFFFFFFFFFFFFF )
+#else
+#define floatx80_default_nan_high 0xFFFF
+#define floatx80_default_nan_low LIT64( 0xC000000000000000 )
+#endif
+
+const floatx80 floatx80_default_nan = make_floatx80(floatx80_default_nan_high,
+ floatx80_default_nan_low);
+
+/*----------------------------------------------------------------------------
+| The pattern for a default generated quadruple-precision NaN. The `high' and
+| `low' values hold the most- and least-significant bits, respectively.
+*----------------------------------------------------------------------------*/
+#if SNAN_BIT_IS_ONE
+#define float128_default_nan_high LIT64( 0x7FFF7FFFFFFFFFFF )
+#define float128_default_nan_low LIT64( 0xFFFFFFFFFFFFFFFF )
+#else
+#define float128_default_nan_high LIT64( 0xFFFF800000000000 )
+#define float128_default_nan_low LIT64( 0x0000000000000000 )
+#endif
+
+const float128 float128_default_nan = make_float128(float128_default_nan_high,
+ float128_default_nan_low);
/*----------------------------------------------------------------------------
| Raises the exceptions specified by `flags'. Floating-point traps can be
void float_raise( int8 flags STATUS_PARAM )
{
-
STATUS(float_exception_flags) |= flags;
-
}
/*----------------------------------------------------------------------------
*----------------------------------------------------------------------------*/
typedef struct {
flag sign;
- bits64 high, low;
+ uint64_t high, low;
} commonNaNT;
/*----------------------------------------------------------------------------
-| The pattern for a default generated single-precision NaN.
+| Returns 1 if the half-precision floating-point value `a' is a quiet
+| NaN; otherwise returns 0.
*----------------------------------------------------------------------------*/
-#define float32_default_nan 0xFFC00000
+
+int float16_is_quiet_nan(float16 a_)
+{
+ uint16_t a = float16_val(a_);
+#if SNAN_BIT_IS_ONE
+ return (((a >> 9) & 0x3F) == 0x3E) && (a & 0x1FF);
+#else
+ return ((a & ~0x8000) >= 0x7c80);
+#endif
+}
/*----------------------------------------------------------------------------
-| Returns 1 if the single-precision floating-point value `a' is a NaN;
-| otherwise returns 0.
+| Returns 1 if the half-precision floating-point value `a' is a signaling
+| NaN; otherwise returns 0.
*----------------------------------------------------------------------------*/
-int float32_is_nan( float32 a )
+int float16_is_signaling_nan(float16 a_)
{
+ uint16_t a = float16_val(a_);
+#if SNAN_BIT_IS_ONE
+ return ((a & ~0x8000) >= 0x7c80);
+#else
+ return (((a >> 9) & 0x3F) == 0x3E) && (a & 0x1FF);
+#endif
+}
- return ( 0xFF000000 < (bits32) ( a<<1 ) );
+/*----------------------------------------------------------------------------
+| Returns a quiet NaN if the half-precision floating point value `a' is a
+| signaling NaN; otherwise returns `a'.
+*----------------------------------------------------------------------------*/
+float16 float16_maybe_silence_nan(float16 a_)
+{
+ if (float16_is_signaling_nan(a_)) {
+#if SNAN_BIT_IS_ONE
+# if defined(TARGET_MIPS) || defined(TARGET_SH4) || defined(TARGET_UNICORE32)
+ return float16_default_nan;
+# else
+# error Rules for silencing a signaling NaN are target-specific
+# endif
+#else
+ uint16_t a = float16_val(a_);
+ a |= (1 << 9);
+ return make_float16(a);
+#endif
+ }
+ return a_;
+}
+
+/*----------------------------------------------------------------------------
+| Returns the result of converting the half-precision floating-point NaN
+| `a' to the canonical NaN format. If `a' is a signaling NaN, the invalid
+| exception is raised.
+*----------------------------------------------------------------------------*/
+
+static commonNaNT float16ToCommonNaN( float16 a STATUS_PARAM )
+{
+ commonNaNT z;
+ if ( float16_is_signaling_nan( a ) ) float_raise( float_flag_invalid STATUS_VAR );
+ z.sign = float16_val(a) >> 15;
+ z.low = 0;
+ z.high = ((uint64_t) float16_val(a))<<54;
+ return z;
}
/*----------------------------------------------------------------------------
-| Returns 1 if the single-precision floating-point value `a' is a signaling
+| Returns the result of converting the canonical NaN `a' to the half-
+| precision floating-point format.
+*----------------------------------------------------------------------------*/
+
+static float16 commonNaNToFloat16(commonNaNT a STATUS_PARAM)
+{
+ uint16_t mantissa = a.high>>54;
+
+ if (STATUS(default_nan_mode)) {
+ return float16_default_nan;
+ }
+
+ if (mantissa) {
+ return make_float16(((((uint16_t) a.sign) << 15)
+ | (0x1F << 10) | mantissa));
+ } else {
+ return float16_default_nan;
+ }
+}
+
+/*----------------------------------------------------------------------------
+| Returns 1 if the single-precision floating-point value `a' is a quiet
| NaN; otherwise returns 0.
*----------------------------------------------------------------------------*/
-int float32_is_signaling_nan( float32 a )
+int float32_is_quiet_nan( float32 a_ )
{
+ uint32_t a = float32_val(a_);
+#if SNAN_BIT_IS_ONE
+ return ( ( ( a>>22 ) & 0x1FF ) == 0x1FE ) && ( a & 0x003FFFFF );
+#else
+ return ( 0xFF800000 <= (uint32_t) ( a<<1 ) );
+#endif
+}
+/*----------------------------------------------------------------------------
+| Returns 1 if the single-precision floating-point value `a' is a signaling
+| NaN; otherwise returns 0.
+*----------------------------------------------------------------------------*/
+
+int float32_is_signaling_nan( float32 a_ )
+{
+ uint32_t a = float32_val(a_);
+#if SNAN_BIT_IS_ONE
+ return ( 0xFF800000 <= (uint32_t) ( a<<1 ) );
+#else
return ( ( ( a>>22 ) & 0x1FF ) == 0x1FE ) && ( a & 0x003FFFFF );
+#endif
+}
+/*----------------------------------------------------------------------------
+| Returns a quiet NaN if the single-precision floating point value `a' is a
+| signaling NaN; otherwise returns `a'.
+*----------------------------------------------------------------------------*/
+
+float32 float32_maybe_silence_nan( float32 a_ )
+{
+ if (float32_is_signaling_nan(a_)) {
+#if SNAN_BIT_IS_ONE
+# if defined(TARGET_MIPS) || defined(TARGET_SH4) || defined(TARGET_UNICORE32)
+ return float32_default_nan;
+# else
+# error Rules for silencing a signaling NaN are target-specific
+# endif
+#else
+ uint32_t a = float32_val(a_);
+ a |= (1 << 22);
+ return make_float32(a);
+#endif
+ }
+ return a_;
}
/*----------------------------------------------------------------------------
commonNaNT z;
if ( float32_is_signaling_nan( a ) ) float_raise( float_flag_invalid STATUS_VAR );
- z.sign = a>>31;
+ z.sign = float32_val(a)>>31;
z.low = 0;
- z.high = ( (bits64) a )<<41;
+ z.high = ( (uint64_t) float32_val(a) )<<41;
return z;
-
}
/*----------------------------------------------------------------------------
| precision floating-point format.
*----------------------------------------------------------------------------*/
-static float32 commonNaNToFloat32( commonNaNT a )
+static float32 commonNaNToFloat32( commonNaNT a STATUS_PARAM)
{
+ uint32_t mantissa = a.high>>41;
- return ( ( (bits32) a.sign )<<31 ) | 0x7FC00000 | ( a.high>>41 );
+ if ( STATUS(default_nan_mode) ) {
+ return float32_default_nan;
+ }
+ if ( mantissa )
+ return make_float32(
+ ( ( (uint32_t) a.sign )<<31 ) | 0x7F800000 | ( a.high>>41 ) );
+ else
+ return float32_default_nan;
+}
+
+/*----------------------------------------------------------------------------
+| Select which NaN to propagate for a two-input operation.
+| IEEE754 doesn't specify all the details of this, so the
+| algorithm is target-specific.
+| The routine is passed various bits of information about the
+| two NaNs and should return 0 to select NaN a and 1 for NaN b.
+| Note that signalling NaNs are always squashed to quiet NaNs
+| by the caller, by calling floatXX_maybe_silence_nan() before
+| returning them.
+|
+| aIsLargerSignificand is only valid if both a and b are NaNs
+| of some kind, and is true if a has the larger significand,
+| or if both a and b have the same significand but a is
+| positive but b is negative. It is only needed for the x87
+| tie-break rule.
+*----------------------------------------------------------------------------*/
+
+#if defined(TARGET_ARM)
+static int pickNaN(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
+ flag aIsLargerSignificand)
+{
+ /* ARM mandated NaN propagation rules: take the first of:
+ * 1. A if it is signaling
+ * 2. B if it is signaling
+ * 3. A (quiet)
+ * 4. B (quiet)
+ * A signaling NaN is always quietened before returning it.
+ */
+ if (aIsSNaN) {
+ return 0;
+ } else if (bIsSNaN) {
+ return 1;
+ } else if (aIsQNaN) {
+ return 0;
+ } else {
+ return 1;
+ }
}
+#elif defined(TARGET_MIPS)
+static int pickNaN(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
+ flag aIsLargerSignificand)
+{
+ /* According to MIPS specifications, if one of the two operands is
+ * a sNaN, a new qNaN has to be generated. This is done in
+ * floatXX_maybe_silence_nan(). For qNaN inputs the specifications
+ * says: "When possible, this QNaN result is one of the operand QNaN
+ * values." In practice it seems that most implementations choose
+ * the first operand if both operands are qNaN. In short this gives
+ * the following rules:
+ * 1. A if it is signaling
+ * 2. B if it is signaling
+ * 3. A (quiet)
+ * 4. B (quiet)
+ * A signaling NaN is always silenced before returning it.
+ */
+ if (aIsSNaN) {
+ return 0;
+ } else if (bIsSNaN) {
+ return 1;
+ } else if (aIsQNaN) {
+ return 0;
+ } else {
+ return 1;
+ }
+}
+#elif defined(TARGET_PPC)
+static int pickNaN(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
+ flag aIsLargerSignificand)
+{
+ /* PowerPC propagation rules:
+ * 1. A if it sNaN or qNaN
+ * 2. B if it sNaN or qNaN
+ * A signaling NaN is always silenced before returning it.
+ */
+ if (aIsSNaN || aIsQNaN) {
+ return 0;
+ } else {
+ return 1;
+ }
+}
+#else
+static int pickNaN(flag aIsQNaN, flag aIsSNaN, flag bIsQNaN, flag bIsSNaN,
+ flag aIsLargerSignificand)
+{
+ /* This implements x87 NaN propagation rules:
+ * SNaN + QNaN => return the QNaN
+ * two SNaNs => return the one with the larger significand, silenced
+ * two QNaNs => return the one with the larger significand
+ * SNaN and a non-NaN => return the SNaN, silenced
+ * QNaN and a non-NaN => return the QNaN
+ *
+ * If we get down to comparing significands and they are the same,
+ * return the NaN with the positive sign bit (if any).
+ */
+ if (aIsSNaN) {
+ if (bIsSNaN) {
+ return aIsLargerSignificand ? 0 : 1;
+ }
+ return bIsQNaN ? 1 : 0;
+ }
+ else if (aIsQNaN) {
+ if (bIsSNaN || !bIsQNaN)
+ return 0;
+ else {
+ return aIsLargerSignificand ? 0 : 1;
+ }
+ } else {
+ return 1;
+ }
+}
+#endif
/*----------------------------------------------------------------------------
| Takes two single-precision floating-point values `a' and `b', one of which
static float32 propagateFloat32NaN( float32 a, float32 b STATUS_PARAM)
{
- flag aIsNaN, aIsSignalingNaN, bIsNaN, bIsSignalingNaN;
+ flag aIsQuietNaN, aIsSignalingNaN, bIsQuietNaN, bIsSignalingNaN;
+ flag aIsLargerSignificand;
+ uint32_t av, bv;
- aIsNaN = float32_is_nan( a );
+ aIsQuietNaN = float32_is_quiet_nan( a );
aIsSignalingNaN = float32_is_signaling_nan( a );
- bIsNaN = float32_is_nan( b );
+ bIsQuietNaN = float32_is_quiet_nan( b );
bIsSignalingNaN = float32_is_signaling_nan( b );
- a |= 0x00400000;
- b |= 0x00400000;
+ av = float32_val(a);
+ bv = float32_val(b);
+
if ( aIsSignalingNaN | bIsSignalingNaN ) float_raise( float_flag_invalid STATUS_VAR);
- if ( aIsSignalingNaN ) {
- if ( bIsSignalingNaN ) goto returnLargerSignificand;
- return bIsNaN ? b : a;
- }
- else if ( aIsNaN ) {
- if ( bIsSignalingNaN | ! bIsNaN ) return a;
- returnLargerSignificand:
- if ( (bits32) ( a<<1 ) < (bits32) ( b<<1 ) ) return b;
- if ( (bits32) ( b<<1 ) < (bits32) ( a<<1 ) ) return a;
- return ( a < b ) ? a : b;
- }
- else {
- return b;
+
+ if ( STATUS(default_nan_mode) )
+ return float32_default_nan;
+
+ if ((uint32_t)(av<<1) < (uint32_t)(bv<<1)) {
+ aIsLargerSignificand = 0;
+ } else if ((uint32_t)(bv<<1) < (uint32_t)(av<<1)) {
+ aIsLargerSignificand = 1;
+ } else {
+ aIsLargerSignificand = (av < bv) ? 1 : 0;
}
+ if (pickNaN(aIsQuietNaN, aIsSignalingNaN, bIsQuietNaN, bIsSignalingNaN,
+ aIsLargerSignificand)) {
+ return float32_maybe_silence_nan(b);
+ } else {
+ return float32_maybe_silence_nan(a);
+ }
}
/*----------------------------------------------------------------------------
-| The pattern for a default generated double-precision NaN.
-*----------------------------------------------------------------------------*/
-#define float64_default_nan LIT64( 0xFFF8000000000000 )
-
-/*----------------------------------------------------------------------------
-| Returns 1 if the double-precision floating-point value `a' is a NaN;
-| otherwise returns 0.
+| Returns 1 if the double-precision floating-point value `a' is a quiet
+| NaN; otherwise returns 0.
*----------------------------------------------------------------------------*/
-int float64_is_nan( float64 a )
+int float64_is_quiet_nan( float64 a_ )
{
-
- return ( LIT64( 0xFFE0000000000000 ) < (bits64) ( a<<1 ) );
-
+ uint64_t a = float64_val(a_);
+#if SNAN_BIT_IS_ONE
+ return
+ ( ( ( a>>51 ) & 0xFFF ) == 0xFFE )
+ && ( a & LIT64( 0x0007FFFFFFFFFFFF ) );
+#else
+ return ( LIT64( 0xFFF0000000000000 ) <= (uint64_t) ( a<<1 ) );
+#endif
}
/*----------------------------------------------------------------------------
| NaN; otherwise returns 0.
*----------------------------------------------------------------------------*/
-int float64_is_signaling_nan( float64 a )
+int float64_is_signaling_nan( float64 a_ )
{
-
+ uint64_t a = float64_val(a_);
+#if SNAN_BIT_IS_ONE
+ return ( LIT64( 0xFFF0000000000000 ) <= (uint64_t) ( a<<1 ) );
+#else
return
( ( ( a>>51 ) & 0xFFF ) == 0xFFE )
&& ( a & LIT64( 0x0007FFFFFFFFFFFF ) );
+#endif
+}
+
+/*----------------------------------------------------------------------------
+| Returns a quiet NaN if the double-precision floating point value `a' is a
+| signaling NaN; otherwise returns `a'.
+*----------------------------------------------------------------------------*/
+float64 float64_maybe_silence_nan( float64 a_ )
+{
+ if (float64_is_signaling_nan(a_)) {
+#if SNAN_BIT_IS_ONE
+# if defined(TARGET_MIPS) || defined(TARGET_SH4) || defined(TARGET_UNICORE32)
+ return float64_default_nan;
+# else
+# error Rules for silencing a signaling NaN are target-specific
+# endif
+#else
+ uint64_t a = float64_val(a_);
+ a |= LIT64( 0x0008000000000000 );
+ return make_float64(a);
+#endif
+ }
+ return a_;
}
/*----------------------------------------------------------------------------
commonNaNT z;
if ( float64_is_signaling_nan( a ) ) float_raise( float_flag_invalid STATUS_VAR);
- z.sign = a>>63;
+ z.sign = float64_val(a)>>63;
z.low = 0;
- z.high = a<<12;
+ z.high = float64_val(a)<<12;
return z;
-
}
/*----------------------------------------------------------------------------
| precision floating-point format.
*----------------------------------------------------------------------------*/
-static float64 commonNaNToFloat64( commonNaNT a )
+static float64 commonNaNToFloat64( commonNaNT a STATUS_PARAM)
{
+ uint64_t mantissa = a.high>>12;
- return
- ( ( (bits64) a.sign )<<63 )
- | LIT64( 0x7FF8000000000000 )
- | ( a.high>>12 );
+ if ( STATUS(default_nan_mode) ) {
+ return float64_default_nan;
+ }
+ if ( mantissa )
+ return make_float64(
+ ( ( (uint64_t) a.sign )<<63 )
+ | LIT64( 0x7FF0000000000000 )
+ | ( a.high>>12 ));
+ else
+ return float64_default_nan;
}
/*----------------------------------------------------------------------------
static float64 propagateFloat64NaN( float64 a, float64 b STATUS_PARAM)
{
- flag aIsNaN, aIsSignalingNaN, bIsNaN, bIsSignalingNaN;
+ flag aIsQuietNaN, aIsSignalingNaN, bIsQuietNaN, bIsSignalingNaN;
+ flag aIsLargerSignificand;
+ uint64_t av, bv;
- aIsNaN = float64_is_nan( a );
+ aIsQuietNaN = float64_is_quiet_nan( a );
aIsSignalingNaN = float64_is_signaling_nan( a );
- bIsNaN = float64_is_nan( b );
+ bIsQuietNaN = float64_is_quiet_nan( b );
bIsSignalingNaN = float64_is_signaling_nan( b );
- a |= LIT64( 0x0008000000000000 );
- b |= LIT64( 0x0008000000000000 );
+ av = float64_val(a);
+ bv = float64_val(b);
+
if ( aIsSignalingNaN | bIsSignalingNaN ) float_raise( float_flag_invalid STATUS_VAR);
- if ( aIsSignalingNaN ) {
- if ( bIsSignalingNaN ) goto returnLargerSignificand;
- return bIsNaN ? b : a;
- }
- else if ( aIsNaN ) {
- if ( bIsSignalingNaN | ! bIsNaN ) return a;
- returnLargerSignificand:
- if ( (bits64) ( a<<1 ) < (bits64) ( b<<1 ) ) return b;
- if ( (bits64) ( b<<1 ) < (bits64) ( a<<1 ) ) return a;
- return ( a < b ) ? a : b;
- }
- else {
- return b;
- }
-}
+ if ( STATUS(default_nan_mode) )
+ return float64_default_nan;
-#ifdef FLOATX80
+ if ((uint64_t)(av<<1) < (uint64_t)(bv<<1)) {
+ aIsLargerSignificand = 0;
+ } else if ((uint64_t)(bv<<1) < (uint64_t)(av<<1)) {
+ aIsLargerSignificand = 1;
+ } else {
+ aIsLargerSignificand = (av < bv) ? 1 : 0;
+ }
-/*----------------------------------------------------------------------------
-| The pattern for a default generated extended double-precision NaN. The
-| `high' and `low' values hold the most- and least-significant bits,
-| respectively.
-*----------------------------------------------------------------------------*/
-#define floatx80_default_nan_high 0xFFFF
-#define floatx80_default_nan_low LIT64( 0xC000000000000000 )
+ if (pickNaN(aIsQuietNaN, aIsSignalingNaN, bIsQuietNaN, bIsSignalingNaN,
+ aIsLargerSignificand)) {
+ return float64_maybe_silence_nan(b);
+ } else {
+ return float64_maybe_silence_nan(a);
+ }
+}
/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point value `a' is a
-| NaN; otherwise returns 0.
+| quiet NaN; otherwise returns 0. This slightly differs from the same
+| function for other types as floatx80 has an explicit bit.
*----------------------------------------------------------------------------*/
-int floatx80_is_nan( floatx80 a )
+int floatx80_is_quiet_nan( floatx80 a )
{
+#if SNAN_BIT_IS_ONE
+ uint64_t aLow;
- return ( ( a.high & 0x7FFF ) == 0x7FFF ) && (bits64) ( a.low<<1 );
-
+ aLow = a.low & ~ LIT64( 0x4000000000000000 );
+ return
+ ( ( a.high & 0x7FFF ) == 0x7FFF )
+ && (uint64_t) ( aLow<<1 )
+ && ( a.low == aLow );
+#else
+ return ( ( a.high & 0x7FFF ) == 0x7FFF )
+ && (LIT64( 0x8000000000000000 ) <= ((uint64_t) ( a.low<<1 )));
+#endif
}
/*----------------------------------------------------------------------------
| Returns 1 if the extended double-precision floating-point value `a' is a
-| signaling NaN; otherwise returns 0.
+| signaling NaN; otherwise returns 0. This slightly differs from the same
+| function for other types as floatx80 has an explicit bit.
*----------------------------------------------------------------------------*/
int floatx80_is_signaling_nan( floatx80 a )
{
- bits64 aLow;
+#if SNAN_BIT_IS_ONE
+ return ( ( a.high & 0x7FFF ) == 0x7FFF )
+ && (LIT64( 0x8000000000000000 ) <= ((uint64_t) ( a.low<<1 )));
+#else
+ uint64_t aLow;
aLow = a.low & ~ LIT64( 0x4000000000000000 );
return
( ( a.high & 0x7FFF ) == 0x7FFF )
- && (bits64) ( aLow<<1 )
+ && (uint64_t) ( aLow<<1 )
&& ( a.low == aLow );
+#endif
+}
+
+/*----------------------------------------------------------------------------
+| Returns a quiet NaN if the extended double-precision floating point value
+| `a' is a signaling NaN; otherwise returns `a'.
+*----------------------------------------------------------------------------*/
+floatx80 floatx80_maybe_silence_nan( floatx80 a )
+{
+ if (floatx80_is_signaling_nan(a)) {
+#if SNAN_BIT_IS_ONE
+# if defined(TARGET_MIPS) || defined(TARGET_SH4) || defined(TARGET_UNICORE32)
+ a.low = floatx80_default_nan_low;
+ a.high = floatx80_default_nan_high;
+# else
+# error Rules for silencing a signaling NaN are target-specific
+# endif
+#else
+ a.low |= LIT64( 0xC000000000000000 );
+ return a;
+#endif
+ }
+ return a;
}
/*----------------------------------------------------------------------------
commonNaNT z;
if ( floatx80_is_signaling_nan( a ) ) float_raise( float_flag_invalid STATUS_VAR);
- z.sign = a.high>>15;
- z.low = 0;
- z.high = a.low<<1;
+ if ( a.low >> 63 ) {
+ z.sign = a.high >> 15;
+ z.low = 0;
+ z.high = a.low << 1;
+ } else {
+ z.sign = floatx80_default_nan_high >> 15;
+ z.low = 0;
+ z.high = floatx80_default_nan_low << 1;
+ }
return z;
-
}
/*----------------------------------------------------------------------------
| double-precision floating-point format.
*----------------------------------------------------------------------------*/
-static floatx80 commonNaNToFloatx80( commonNaNT a )
+static floatx80 commonNaNToFloatx80( commonNaNT a STATUS_PARAM)
{
floatx80 z;
- z.low = LIT64( 0xC000000000000000 ) | ( a.high>>1 );
- z.high = ( ( (bits16) a.sign )<<15 ) | 0x7FFF;
- return z;
+ if ( STATUS(default_nan_mode) ) {
+ z.low = floatx80_default_nan_low;
+ z.high = floatx80_default_nan_high;
+ return z;
+ }
+
+ if (a.high >> 1) {
+ z.low = LIT64( 0x8000000000000000 ) | a.high >> 1;
+ z.high = ( ( (uint16_t) a.sign )<<15 ) | 0x7FFF;
+ } else {
+ z.low = floatx80_default_nan_low;
+ z.high = floatx80_default_nan_high;
+ }
+ return z;
}
/*----------------------------------------------------------------------------
static floatx80 propagateFloatx80NaN( floatx80 a, floatx80 b STATUS_PARAM)
{
- flag aIsNaN, aIsSignalingNaN, bIsNaN, bIsSignalingNaN;
+ flag aIsQuietNaN, aIsSignalingNaN, bIsQuietNaN, bIsSignalingNaN;
+ flag aIsLargerSignificand;
- aIsNaN = floatx80_is_nan( a );
+ aIsQuietNaN = floatx80_is_quiet_nan( a );
aIsSignalingNaN = floatx80_is_signaling_nan( a );
- bIsNaN = floatx80_is_nan( b );
+ bIsQuietNaN = floatx80_is_quiet_nan( b );
bIsSignalingNaN = floatx80_is_signaling_nan( b );
- a.low |= LIT64( 0xC000000000000000 );
- b.low |= LIT64( 0xC000000000000000 );
+
if ( aIsSignalingNaN | bIsSignalingNaN ) float_raise( float_flag_invalid STATUS_VAR);
- if ( aIsSignalingNaN ) {
- if ( bIsSignalingNaN ) goto returnLargerSignificand;
- return bIsNaN ? b : a;
- }
- else if ( aIsNaN ) {
- if ( bIsSignalingNaN | ! bIsNaN ) return a;
- returnLargerSignificand:
- if ( a.low < b.low ) return b;
- if ( b.low < a.low ) return a;
- return ( a.high < b.high ) ? a : b;
+
+ if ( STATUS(default_nan_mode) ) {
+ a.low = floatx80_default_nan_low;
+ a.high = floatx80_default_nan_high;
+ return a;
}
- else {
- return b;
+
+ if (a.low < b.low) {
+ aIsLargerSignificand = 0;
+ } else if (b.low < a.low) {
+ aIsLargerSignificand = 1;
+ } else {
+ aIsLargerSignificand = (a.high < b.high) ? 1 : 0;
}
+ if (pickNaN(aIsQuietNaN, aIsSignalingNaN, bIsQuietNaN, bIsSignalingNaN,
+ aIsLargerSignificand)) {
+ return floatx80_maybe_silence_nan(b);
+ } else {
+ return floatx80_maybe_silence_nan(a);
+ }
}
-#endif
-
-#ifdef FLOAT128
-
/*----------------------------------------------------------------------------
-| The pattern for a default generated quadruple-precision NaN. The `high' and
-| `low' values hold the most- and least-significant bits, respectively.
-*----------------------------------------------------------------------------*/
-#define float128_default_nan_high LIT64( 0xFFFF800000000000 )
-#define float128_default_nan_low LIT64( 0x0000000000000000 )
-
-/*----------------------------------------------------------------------------
-| Returns 1 if the quadruple-precision floating-point value `a' is a NaN;
-| otherwise returns 0.
+| Returns 1 if the quadruple-precision floating-point value `a' is a quiet
+| NaN; otherwise returns 0.
*----------------------------------------------------------------------------*/
-int float128_is_nan( float128 a )
+int float128_is_quiet_nan( float128 a )
{
-
+#if SNAN_BIT_IS_ONE
return
- ( LIT64( 0xFFFE000000000000 ) <= (bits64) ( a.high<<1 ) )
+ ( ( ( a.high>>47 ) & 0xFFFF ) == 0xFFFE )
+ && ( a.low || ( a.high & LIT64( 0x00007FFFFFFFFFFF ) ) );
+#else
+ return
+ ( LIT64( 0xFFFE000000000000 ) <= (uint64_t) ( a.high<<1 ) )
&& ( a.low || ( a.high & LIT64( 0x0000FFFFFFFFFFFF ) ) );
-
+#endif
}
/*----------------------------------------------------------------------------
int float128_is_signaling_nan( float128 a )
{
-
+#if SNAN_BIT_IS_ONE
+ return
+ ( LIT64( 0xFFFE000000000000 ) <= (uint64_t) ( a.high<<1 ) )
+ && ( a.low || ( a.high & LIT64( 0x0000FFFFFFFFFFFF ) ) );
+#else
return
( ( ( a.high>>47 ) & 0xFFFF ) == 0xFFFE )
&& ( a.low || ( a.high & LIT64( 0x00007FFFFFFFFFFF ) ) );
+#endif
+}
+
+/*----------------------------------------------------------------------------
+| Returns a quiet NaN if the quadruple-precision floating point value `a' is
+| a signaling NaN; otherwise returns `a'.
+*----------------------------------------------------------------------------*/
+float128 float128_maybe_silence_nan( float128 a )
+{
+ if (float128_is_signaling_nan(a)) {
+#if SNAN_BIT_IS_ONE
+# if defined(TARGET_MIPS) || defined(TARGET_SH4) || defined(TARGET_UNICORE32)
+ a.low = float128_default_nan_low;
+ a.high = float128_default_nan_high;
+# else
+# error Rules for silencing a signaling NaN are target-specific
+# endif
+#else
+ a.high |= LIT64( 0x0000800000000000 );
+ return a;
+#endif
+ }
+ return a;
}
/*----------------------------------------------------------------------------
z.sign = a.high>>63;
shortShift128Left( a.high, a.low, 16, &z.high, &z.low );
return z;
-
}
/*----------------------------------------------------------------------------
| precision floating-point format.
*----------------------------------------------------------------------------*/
-static float128 commonNaNToFloat128( commonNaNT a )
+static float128 commonNaNToFloat128( commonNaNT a STATUS_PARAM)
{
float128 z;
+ if ( STATUS(default_nan_mode) ) {
+ z.low = float128_default_nan_low;
+ z.high = float128_default_nan_high;
+ return z;
+ }
+
shift128Right( a.high, a.low, 16, &z.high, &z.low );
- z.high |= ( ( (bits64) a.sign )<<63 ) | LIT64( 0x7FFF800000000000 );
+ z.high |= ( ( (uint64_t) a.sign )<<63 ) | LIT64( 0x7FFF000000000000 );
return z;
-
}
/*----------------------------------------------------------------------------
static float128 propagateFloat128NaN( float128 a, float128 b STATUS_PARAM)
{
- flag aIsNaN, aIsSignalingNaN, bIsNaN, bIsSignalingNaN;
+ flag aIsQuietNaN, aIsSignalingNaN, bIsQuietNaN, bIsSignalingNaN;
+ flag aIsLargerSignificand;
- aIsNaN = float128_is_nan( a );
+ aIsQuietNaN = float128_is_quiet_nan( a );
aIsSignalingNaN = float128_is_signaling_nan( a );
- bIsNaN = float128_is_nan( b );
+ bIsQuietNaN = float128_is_quiet_nan( b );
bIsSignalingNaN = float128_is_signaling_nan( b );
- a.high |= LIT64( 0x0000800000000000 );
- b.high |= LIT64( 0x0000800000000000 );
+
if ( aIsSignalingNaN | bIsSignalingNaN ) float_raise( float_flag_invalid STATUS_VAR);
- if ( aIsSignalingNaN ) {
- if ( bIsSignalingNaN ) goto returnLargerSignificand;
- return bIsNaN ? b : a;
- }
- else if ( aIsNaN ) {
- if ( bIsSignalingNaN | ! bIsNaN ) return a;
- returnLargerSignificand:
- if ( lt128( a.high<<1, a.low, b.high<<1, b.low ) ) return b;
- if ( lt128( b.high<<1, b.low, a.high<<1, a.low ) ) return a;
- return ( a.high < b.high ) ? a : b;
+
+ if ( STATUS(default_nan_mode) ) {
+ a.low = float128_default_nan_low;
+ a.high = float128_default_nan_high;
+ return a;
}
- else {
- return b;
+
+ if (lt128(a.high<<1, a.low, b.high<<1, b.low)) {
+ aIsLargerSignificand = 0;
+ } else if (lt128(b.high<<1, b.low, a.high<<1, a.low)) {
+ aIsLargerSignificand = 1;
+ } else {
+ aIsLargerSignificand = (a.high < b.high) ? 1 : 0;
}
+ if (pickNaN(aIsQuietNaN, aIsSignalingNaN, bIsQuietNaN, bIsSignalingNaN,
+ aIsLargerSignificand)) {
+ return float128_maybe_silence_nan(b);
+ } else {
+ return float128_maybe_silence_nan(a);
+ }
}
-#endif
-
projects / qemu.git / blobdiff