b6cbf7203b
This patch imports the unmodified current version of NetBSD libc. The NetBSD includes are in /nbsd_include, while the libc code itself is split between lib/nbsd_libc and common/lib/libc.
465 lines
15 KiB
Plaintext
465 lines
15 KiB
Plaintext
|
|
/*
|
|
===============================================================================
|
|
|
|
This C source fragment is part of the SoftFloat IEC/IEEE Floating-point
|
|
Arithmetic Package, Release 2a.
|
|
|
|
Written by John R. Hauser. This work was made possible in part by the
|
|
International Computer Science Institute, located at Suite 600, 1947 Center
|
|
Street, Berkeley, California 94704. Funding was partially provided by the
|
|
National Science Foundation under grant MIP-9311980. The original version
|
|
of this code was written as part of a project to build a fixed-point vector
|
|
processor in collaboration with the University of California at Berkeley,
|
|
overseen by Profs. Nelson Morgan and John Wawrzynek. More information
|
|
is available through the Web page `http://HTTP.CS.Berkeley.EDU/~jhauser/
|
|
arithmetic/SoftFloat.html'.
|
|
|
|
THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort
|
|
has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
|
|
TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO
|
|
PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
|
|
AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
|
|
|
|
Derivative works are acceptable, even for commercial purposes, so long as
|
|
(1) they include prominent notice that the work is derivative, and (2) they
|
|
include prominent notice akin to these four paragraphs for those parts of
|
|
this code that are retained.
|
|
|
|
===============================================================================
|
|
*/
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Underflow tininess-detection mode, statically initialized to default value.
|
|
(The declaration in `softfloat.h' must match the `int8' type here.)
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
int8 float_detect_tininess = float_tininess_after_rounding;
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Raises the exceptions specified by `flags'. Floating-point traps can be
|
|
defined here if desired. It is currently not possible for such a trap to
|
|
substitute a result value. If traps are not implemented, this routine
|
|
should be simply `float_exception_flags |= flags;'.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
void float_raise( int8 flags )
|
|
{
|
|
|
|
float_exception_flags |= flags;
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Internal canonical NaN format.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
typedef struct {
|
|
flag sign;
|
|
bits64 high, low;
|
|
} commonNaNT;
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
The pattern for a default generated single-precision NaN.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
#define float32_default_nan 0xFFFFFFFF
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns 1 if the single-precision floating-point value `a' is a NaN;
|
|
otherwise returns 0.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
flag float32_is_nan( float32 a )
|
|
{
|
|
|
|
return ( 0xFF000000 < (bits32) ( a<<1 ) );
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns 1 if the single-precision floating-point value `a' is a signaling
|
|
NaN; otherwise returns 0.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
flag float32_is_signaling_nan( float32 a )
|
|
{
|
|
|
|
return ( ( ( a>>22 ) & 0x1FF ) == 0x1FE ) && ( a & 0x003FFFFF );
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns the result of converting the single-precision floating-point NaN
|
|
`a' to the canonical NaN format. If `a' is a signaling NaN, the invalid
|
|
exception is raised.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static commonNaNT float32ToCommonNaN( float32 a )
|
|
{
|
|
commonNaNT z;
|
|
|
|
if ( float32_is_signaling_nan( a ) ) float_raise( float_flag_invalid );
|
|
z.sign = a>>31;
|
|
z.low = 0;
|
|
z.high = ( (bits64) a )<<41;
|
|
return z;
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns the result of converting the canonical NaN `a' to the single-
|
|
precision floating-point format.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static float32 commonNaNToFloat32( commonNaNT a )
|
|
{
|
|
|
|
return ( ( (bits32) a.sign )<<31 ) | 0x7FC00000 | ( a.high>>41 );
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Takes two single-precision floating-point values `a' and `b', one of which
|
|
is a NaN, and returns the appropriate NaN result. If either `a' or `b' is a
|
|
signaling NaN, the invalid exception is raised.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static float32 propagateFloat32NaN( float32 a, float32 b )
|
|
{
|
|
flag aIsNaN, aIsSignalingNaN, bIsNaN, bIsSignalingNaN;
|
|
|
|
aIsNaN = float32_is_nan( a );
|
|
aIsSignalingNaN = float32_is_signaling_nan( a );
|
|
bIsNaN = float32_is_nan( b );
|
|
bIsSignalingNaN = float32_is_signaling_nan( b );
|
|
a |= 0x00400000;
|
|
b |= 0x00400000;
|
|
if ( aIsSignalingNaN | bIsSignalingNaN ) float_raise( float_flag_invalid );
|
|
if ( aIsNaN ) {
|
|
return ( aIsSignalingNaN & bIsNaN ) ? b : a;
|
|
}
|
|
else {
|
|
return b;
|
|
}
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
The pattern for a default generated double-precision NaN.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
#define float64_default_nan LIT64( 0xFFFFFFFFFFFFFFFF )
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns 1 if the double-precision floating-point value `a' is a NaN;
|
|
otherwise returns 0.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
flag float64_is_nan( float64 a )
|
|
{
|
|
|
|
return ( LIT64( 0xFFE0000000000000 ) < (bits64) ( a<<1 ) );
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns 1 if the double-precision floating-point value `a' is a signaling
|
|
NaN; otherwise returns 0.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
flag float64_is_signaling_nan( float64 a )
|
|
{
|
|
|
|
return
|
|
( ( ( a>>51 ) & 0xFFF ) == 0xFFE )
|
|
&& ( a & LIT64( 0x0007FFFFFFFFFFFF ) );
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns the result of converting the double-precision floating-point NaN
|
|
`a' to the canonical NaN format. If `a' is a signaling NaN, the invalid
|
|
exception is raised.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static commonNaNT float64ToCommonNaN( float64 a )
|
|
{
|
|
commonNaNT z;
|
|
|
|
if ( float64_is_signaling_nan( a ) ) float_raise( float_flag_invalid );
|
|
z.sign = a>>63;
|
|
z.low = 0;
|
|
z.high = a<<12;
|
|
return z;
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns the result of converting the canonical NaN `a' to the double-
|
|
precision floating-point format.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static float64 commonNaNToFloat64( commonNaNT a )
|
|
{
|
|
|
|
return
|
|
( ( (bits64) a.sign )<<63 )
|
|
| LIT64( 0x7FF8000000000000 )
|
|
| ( a.high>>12 );
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Takes two double-precision floating-point values `a' and `b', one of which
|
|
is a NaN, and returns the appropriate NaN result. If either `a' or `b' is a
|
|
signaling NaN, the invalid exception is raised.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static float64 propagateFloat64NaN( float64 a, float64 b )
|
|
{
|
|
flag aIsNaN, aIsSignalingNaN, bIsNaN, bIsSignalingNaN;
|
|
|
|
aIsNaN = float64_is_nan( a );
|
|
aIsSignalingNaN = float64_is_signaling_nan( a );
|
|
bIsNaN = float64_is_nan( b );
|
|
bIsSignalingNaN = float64_is_signaling_nan( b );
|
|
a |= LIT64( 0x0008000000000000 );
|
|
b |= LIT64( 0x0008000000000000 );
|
|
if ( aIsSignalingNaN | bIsSignalingNaN ) float_raise( float_flag_invalid );
|
|
if ( aIsNaN ) {
|
|
return ( aIsSignalingNaN & bIsNaN ) ? b : a;
|
|
}
|
|
else {
|
|
return b;
|
|
}
|
|
|
|
}
|
|
|
|
#ifdef FLOATX80
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
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( 0xFFFFFFFFFFFFFFFF )
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns 1 if the extended double-precision floating-point value `a' is a
|
|
NaN; otherwise returns 0.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
flag floatx80_is_nan( floatx80 a )
|
|
{
|
|
|
|
return ( ( a.high & 0x7FFF ) == 0x7FFF ) && (bits64) ( a.low<<1 );
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns 1 if the extended double-precision floating-point value `a' is a
|
|
signaling NaN; otherwise returns 0.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
flag floatx80_is_signaling_nan( floatx80 a )
|
|
{
|
|
bits64 aLow;
|
|
|
|
aLow = a.low & ~ LIT64( 0x4000000000000000 );
|
|
return
|
|
( ( a.high & 0x7FFF ) == 0x7FFF )
|
|
&& (bits64) ( aLow<<1 )
|
|
&& ( a.low == aLow );
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns the result of converting the extended double-precision floating-
|
|
point NaN `a' to the canonical NaN format. If `a' is a signaling NaN, the
|
|
invalid exception is raised.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static commonNaNT floatx80ToCommonNaN( floatx80 a )
|
|
{
|
|
commonNaNT z;
|
|
|
|
if ( floatx80_is_signaling_nan( a ) ) float_raise( float_flag_invalid );
|
|
z.sign = a.high>>15;
|
|
z.low = 0;
|
|
z.high = a.low<<1;
|
|
return z;
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns the result of converting the canonical NaN `a' to the extended
|
|
double-precision floating-point format.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static floatx80 commonNaNToFloatx80( commonNaNT a )
|
|
{
|
|
floatx80 z;
|
|
|
|
z.low = LIT64( 0xC000000000000000 ) | ( a.high>>1 );
|
|
z.high = ( ( (bits16) a.sign )<<15 ) | 0x7FFF;
|
|
return z;
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Takes two extended double-precision floating-point values `a' and `b', one
|
|
of which is a NaN, and returns the appropriate NaN result. If either `a' or
|
|
`b' is a signaling NaN, the invalid exception is raised.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static floatx80 propagateFloatx80NaN( floatx80 a, floatx80 b )
|
|
{
|
|
flag aIsNaN, aIsSignalingNaN, bIsNaN, bIsSignalingNaN;
|
|
|
|
aIsNaN = floatx80_is_nan( a );
|
|
aIsSignalingNaN = floatx80_is_signaling_nan( a );
|
|
bIsNaN = floatx80_is_nan( b );
|
|
bIsSignalingNaN = floatx80_is_signaling_nan( b );
|
|
a.low |= LIT64( 0xC000000000000000 );
|
|
b.low |= LIT64( 0xC000000000000000 );
|
|
if ( aIsSignalingNaN | bIsSignalingNaN ) float_raise( float_flag_invalid );
|
|
if ( aIsNaN ) {
|
|
return ( aIsSignalingNaN & bIsNaN ) ? b : a;
|
|
}
|
|
else {
|
|
return b;
|
|
}
|
|
|
|
}
|
|
|
|
#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( 0xFFFFFFFFFFFFFFFF )
|
|
#define float128_default_nan_low LIT64( 0xFFFFFFFFFFFFFFFF )
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns 1 if the quadruple-precision floating-point value `a' is a NaN;
|
|
otherwise returns 0.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
flag float128_is_nan( float128 a )
|
|
{
|
|
|
|
return
|
|
( LIT64( 0xFFFE000000000000 ) <= (bits64) ( a.high<<1 ) )
|
|
&& ( a.low || ( a.high & LIT64( 0x0000FFFFFFFFFFFF ) ) );
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns 1 if the quadruple-precision floating-point value `a' is a
|
|
signaling NaN; otherwise returns 0.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
flag float128_is_signaling_nan( float128 a )
|
|
{
|
|
|
|
return
|
|
( ( ( a.high>>47 ) & 0xFFFF ) == 0xFFFE )
|
|
&& ( a.low || ( a.high & LIT64( 0x00007FFFFFFFFFFF ) ) );
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns the result of converting the quadruple-precision floating-point NaN
|
|
`a' to the canonical NaN format. If `a' is a signaling NaN, the invalid
|
|
exception is raised.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static commonNaNT float128ToCommonNaN( float128 a )
|
|
{
|
|
commonNaNT z;
|
|
|
|
if ( float128_is_signaling_nan( a ) ) float_raise( float_flag_invalid );
|
|
z.sign = a.high>>63;
|
|
shortShift128Left( a.high, a.low, 16, &z.high, &z.low );
|
|
return z;
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Returns the result of converting the canonical NaN `a' to the quadruple-
|
|
precision floating-point format.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static float128 commonNaNToFloat128( commonNaNT a )
|
|
{
|
|
float128 z;
|
|
|
|
shift128Right( a.high, a.low, 16, &z.high, &z.low );
|
|
z.high |= ( ( (bits64) a.sign )<<63 ) | LIT64( 0x7FFF800000000000 );
|
|
return z;
|
|
|
|
}
|
|
|
|
/*
|
|
-------------------------------------------------------------------------------
|
|
Takes two quadruple-precision floating-point values `a' and `b', one of
|
|
which is a NaN, and returns the appropriate NaN result. If either `a' or
|
|
`b' is a signaling NaN, the invalid exception is raised.
|
|
-------------------------------------------------------------------------------
|
|
*/
|
|
static float128 propagateFloat128NaN( float128 a, float128 b )
|
|
{
|
|
flag aIsNaN, aIsSignalingNaN, bIsNaN, bIsSignalingNaN;
|
|
|
|
aIsNaN = float128_is_nan( a );
|
|
aIsSignalingNaN = float128_is_signaling_nan( a );
|
|
bIsNaN = float128_is_nan( b );
|
|
bIsSignalingNaN = float128_is_signaling_nan( b );
|
|
a.high |= LIT64( 0x0000800000000000 );
|
|
b.high |= LIT64( 0x0000800000000000 );
|
|
if ( aIsSignalingNaN | bIsSignalingNaN ) float_raise( float_flag_invalid );
|
|
if ( aIsNaN ) {
|
|
return ( aIsSignalingNaN & bIsNaN ) ? b : a;
|
|
}
|
|
else {
|
|
return b;
|
|
}
|
|
|
|
}
|
|
|
|
#endif
|
|
|