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Diffstat (limited to 'kernel/arch/arm/nwfpe/softfloat-specialize')
| -rw-r--r-- | kernel/arch/arm/nwfpe/softfloat-specialize | 367 |
1 files changed, 367 insertions, 0 deletions
diff --git a/kernel/arch/arm/nwfpe/softfloat-specialize b/kernel/arch/arm/nwfpe/softfloat-specialize new file mode 100644 index 000000000..679a0269d --- /dev/null +++ b/kernel/arch/arm/nwfpe/softfloat-specialize @@ -0,0 +1,367 @@ + +/* +=============================================================================== + +This C source fragment is part of the SoftFloat IEC/IEEE Floating-point +Arithmetic Package, Release 2. + +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://www.jhauser.us/arithmetic/SoftFloat-2b/SoftFloat-source.txt + +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 three 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;'. + +ScottB: November 4, 1998 +Moved this function out of softfloat-specialize into fpmodule.c. +This effectively isolates all the changes required for integrating with the +Linux kernel into fpmodule.c. Porting to NetBSD should only require modifying +fpmodule.c to integrate with the NetBSD kernel (I hope!). +------------------------------------------------------------------------------- +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 ) +{ + //register int lr; + bits64 aLow; + + //__asm__("mov %0, lr" : : "g" (lr)); + //fp_printk("floatx80_is_signalling_nan() called from 0x%08x\n",lr); + 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; + z.__padding = 0; + 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 |