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author | 2015-01-10 21:45:26 +0100 | |
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committer | 2015-01-10 21:45:26 +0100 | |
commit | 45ac9b351e0076c371de4c7453f59567b27b1cb6 (patch) | |
tree | cb61f3cc0623b7a922e8c4121cb31d6264415e24 /3rdparty/softfloat/softfloat.h | |
parent | 27668e9b69348c4b2353893189f38b5381c49d28 (diff) |
Moved softfloat to 3rdparty (nw)
Diffstat (limited to '3rdparty/softfloat/softfloat.h')
-rw-r--r-- | 3rdparty/softfloat/softfloat.h | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/3rdparty/softfloat/softfloat.h b/3rdparty/softfloat/softfloat.h new file mode 100644 index 00000000000..6f4389b10bc --- /dev/null +++ b/3rdparty/softfloat/softfloat.h @@ -0,0 +1,460 @@ + +/*============================================================================ + +This C header file is part of the SoftFloat IEC/IEEE Floating-point Arithmetic +Package, Release 2b. + +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.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 ALL LOSSES, +COSTS, OR OTHER PROBLEMS THEY INCUR DUE TO THE SOFTWARE, AND WHO FURTHERMORE +EFFECTIVELY INDEMNIFY JOHN HAUSER AND THE INTERNATIONAL COMPUTER SCIENCE +INSTITUTE (possibly via similar legal warning) AGAINST ALL LOSSES, COSTS, OR +OTHER PROBLEMS INCURRED BY THEIR CUSTOMERS AND CLIENTS DUE TO THE SOFTWARE. + +Derivative works are acceptable, even for commercial purposes, so long as +(1) the source code for the derivative work includes prominent notice that +the work is derivative, and (2) the source code includes prominent notice with +these four paragraphs for those parts of this code that are retained. + +=============================================================================*/ + +/*---------------------------------------------------------------------------- +| The macro `FLOATX80' must be defined to enable the extended double-precision +| floating-point format `floatx80'. If this macro is not defined, the +| `floatx80' type will not be defined, and none of the functions that either +| input or output the `floatx80' type will be defined. The same applies to +| the `FLOAT128' macro and the quadruple-precision format `float128'. +*----------------------------------------------------------------------------*/ +#define FLOATX80 +#define FLOAT128 + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE floating-point types. +*----------------------------------------------------------------------------*/ +typedef bits32 float32; +typedef bits64 float64; +#ifdef FLOATX80 +typedef struct { + bits16 high; + bits64 low; +} floatx80; +#endif +#ifdef FLOAT128 +typedef struct { + bits64 high, low; +} float128; +#endif + +/*---------------------------------------------------------------------------- +| Primitive arithmetic functions, including multi-word arithmetic, and +| division and square root approximations. (Can be specialized to target if +| desired.) +*----------------------------------------------------------------------------*/ +#include "softfloat-macros" + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE floating-point underflow tininess-detection mode. +*----------------------------------------------------------------------------*/ +extern int8 float_detect_tininess; +enum { + float_tininess_after_rounding = 0, + float_tininess_before_rounding = 1 +}; + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE floating-point rounding mode. +*----------------------------------------------------------------------------*/ +extern int8 float_rounding_mode; +enum { + float_round_nearest_even = 0, + float_round_to_zero = 1, + float_round_down = 2, + float_round_up = 3 +}; + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE floating-point exception flags. +*----------------------------------------------------------------------------*/ +extern int8 float_exception_flags; +enum { + float_flag_invalid = 0x01, float_flag_denormal = 0x02, float_flag_divbyzero = 0x04, float_flag_overflow = 0x08, + float_flag_underflow = 0x10, float_flag_inexact = 0x20 +}; + +/*---------------------------------------------------------------------------- +| Routine to raise any or all of the software IEC/IEEE floating-point +| exception flags. +*----------------------------------------------------------------------------*/ +void float_raise( int8 ); + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE integer-to-floating-point conversion routines. +*----------------------------------------------------------------------------*/ +float32 int32_to_float32( int32 ); +float64 int32_to_float64( int32 ); +#ifdef FLOATX80 +floatx80 int32_to_floatx80( int32 ); +#endif +#ifdef FLOAT128 +float128 int32_to_float128( int32 ); +#endif +float32 int64_to_float32( int64 ); +float64 int64_to_float64( int64 ); +#ifdef FLOATX80 +floatx80 int64_to_floatx80( int64 ); +#endif +#ifdef FLOAT128 +float128 int64_to_float128( int64 ); +#endif + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE single-precision conversion routines. +*----------------------------------------------------------------------------*/ +int32 float32_to_int32( float32 ); +int32 float32_to_int32_round_to_zero( float32 ); +int64 float32_to_int64( float32 ); +int64 float32_to_int64_round_to_zero( float32 ); +float64 float32_to_float64( float32 ); +#ifdef FLOATX80 +floatx80 float32_to_floatx80( float32 ); +#endif +#ifdef FLOAT128 +float128 float32_to_float128( float32 ); +#endif + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE single-precision operations. +*----------------------------------------------------------------------------*/ +float32 float32_round_to_int( float32 ); +float32 float32_add( float32, float32 ); +float32 float32_sub( float32, float32 ); +float32 float32_mul( float32, float32 ); +float32 float32_div( float32, float32 ); +float32 float32_rem( float32, float32 ); +float32 float32_sqrt( float32 ); +flag float32_eq( float32, float32 ); +flag float32_le( float32, float32 ); +flag float32_lt( float32, float32 ); +flag float32_eq_signaling( float32, float32 ); +flag float32_le_quiet( float32, float32 ); +flag float32_lt_quiet( float32, float32 ); +flag float32_is_signaling_nan( float32 ); + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE double-precision conversion routines. +*----------------------------------------------------------------------------*/ +int32 float64_to_int32( float64 ); +int32 float64_to_int32_round_to_zero( float64 ); +int64 float64_to_int64( float64 ); +int64 float64_to_int64_round_to_zero( float64 ); +float32 float64_to_float32( float64 ); +#ifdef FLOATX80 +floatx80 float64_to_floatx80( float64 ); +#endif +#ifdef FLOAT128 +float128 float64_to_float128( float64 ); +#endif + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE double-precision operations. +*----------------------------------------------------------------------------*/ +float64 float64_round_to_int( float64 ); +float64 float64_add( float64, float64 ); +float64 float64_sub( float64, float64 ); +float64 float64_mul( float64, float64 ); +float64 float64_div( float64, float64 ); +float64 float64_rem( float64, float64 ); +float64 float64_sqrt( float64 ); +flag float64_eq( float64, float64 ); +flag float64_le( float64, float64 ); +flag float64_lt( float64, float64 ); +flag float64_eq_signaling( float64, float64 ); +flag float64_le_quiet( float64, float64 ); +flag float64_lt_quiet( float64, float64 ); +flag float64_is_signaling_nan( float64 ); + +#ifdef FLOATX80 + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE extended double-precision conversion routines. +*----------------------------------------------------------------------------*/ +int32 floatx80_to_int32( floatx80 ); +int32 floatx80_to_int32_round_to_zero( floatx80 ); +int64 floatx80_to_int64( floatx80 ); +int64 floatx80_to_int64_round_to_zero( floatx80 ); +float32 floatx80_to_float32( floatx80 ); +float64 floatx80_to_float64( floatx80 ); +#ifdef FLOAT128 +float128 floatx80_to_float128( floatx80 ); +#endif +floatx80 floatx80_scale(floatx80 a, floatx80 b); + +/*---------------------------------------------------------------------------- +| Packs the sign `zSign', exponent `zExp', and significand `zSig' into an +| extended double-precision floating-point value, returning the result. +*----------------------------------------------------------------------------*/ + +INLINE floatx80 packFloatx80( flag zSign, int32 zExp, bits64 zSig ) +{ + floatx80 z; + + z.low = zSig; + z.high = ( ( (bits16) zSign )<<15 ) + zExp; + return z; + +} + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE extended double-precision rounding precision. Valid +| values are 32, 64, and 80. +*----------------------------------------------------------------------------*/ +extern int8 floatx80_rounding_precision; + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE extended double-precision operations. +*----------------------------------------------------------------------------*/ +floatx80 floatx80_round_to_int( floatx80 ); +floatx80 floatx80_add( floatx80, floatx80 ); +floatx80 floatx80_sub( floatx80, floatx80 ); +floatx80 floatx80_mul( floatx80, floatx80 ); +floatx80 floatx80_div( floatx80, floatx80 ); +floatx80 floatx80_rem( floatx80, floatx80 ); +floatx80 floatx80_sqrt( floatx80 ); +flag floatx80_eq( floatx80, floatx80 ); +flag floatx80_le( floatx80, floatx80 ); +flag floatx80_lt( floatx80, floatx80 ); +flag floatx80_eq_signaling( floatx80, floatx80 ); +flag floatx80_le_quiet( floatx80, floatx80 ); +flag floatx80_lt_quiet( floatx80, floatx80 ); +flag floatx80_is_signaling_nan( floatx80 ); + +int floatx80_fsin(floatx80 &a); +int floatx80_fcos(floatx80 &a); +int floatx80_ftan(floatx80 &a); + +floatx80 floatx80_flognp1(floatx80 a); +floatx80 floatx80_flogn(floatx80 a); +floatx80 floatx80_flog2(floatx80 a); +floatx80 floatx80_flog10(floatx80 a); + +// roundAndPackFloatx80 used to be in softfloat-round-pack, is now in softfloat.c +floatx80 roundAndPackFloatx80(int8 roundingPrecision, flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1); + +#endif + +#ifdef FLOAT128 + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE quadruple-precision conversion routines. +*----------------------------------------------------------------------------*/ +int32 float128_to_int32( float128 ); +int32 float128_to_int32_round_to_zero( float128 ); +int64 float128_to_int64( float128 ); +int64 float128_to_int64_round_to_zero( float128 ); +float32 float128_to_float32( float128 ); +float64 float128_to_float64( float128 ); +#ifdef FLOATX80 +floatx80 float128_to_floatx80( float128 ); +#endif + +/*---------------------------------------------------------------------------- +| Software IEC/IEEE quadruple-precision operations. +*----------------------------------------------------------------------------*/ +float128 float128_round_to_int( float128 ); +float128 float128_add( float128, float128 ); +float128 float128_sub( float128, float128 ); +float128 float128_mul( float128, float128 ); +float128 float128_div( float128, float128 ); +float128 float128_rem( float128, float128 ); +float128 float128_sqrt( float128 ); +flag float128_eq( float128, float128 ); +flag float128_le( float128, float128 ); +flag float128_lt( float128, float128 ); +flag float128_eq_signaling( float128, float128 ); +flag float128_le_quiet( float128, float128 ); +flag float128_lt_quiet( float128, float128 ); +flag float128_is_signaling_nan( float128 ); + +/*---------------------------------------------------------------------------- +| Packs the sign `zSign', the exponent `zExp', and the significand formed +| by the concatenation of `zSig0' and `zSig1' into a quadruple-precision +| floating-point value, returning the result. After being shifted into the +| proper positions, the three fields `zSign', `zExp', and `zSig0' are simply +| added together to form the most significant 32 bits of the result. This +| means that any integer portion of `zSig0' will be added into the exponent. +| Since a properly normalized significand will have an integer portion equal +| to 1, the `zExp' input should be 1 less than the desired result exponent +| whenever `zSig0' and `zSig1' concatenated form a complete, normalized +| significand. +*----------------------------------------------------------------------------*/ + +INLINE float128 + packFloat128( flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1 ) +{ + float128 z; + + z.low = zSig1; + z.high = ( ( (bits64) zSign )<<63 ) + ( ( (bits64) zExp )<<48 ) + zSig0; + return z; + +} + +/*---------------------------------------------------------------------------- +| Takes an abstract floating-point value having sign `zSign', exponent `zExp', +| and extended significand formed by the concatenation of `zSig0', `zSig1', +| and `zSig2', and returns the proper quadruple-precision floating-point value +| corresponding to the abstract input. Ordinarily, the abstract value is +| simply rounded and packed into the quadruple-precision format, with the +| inexact exception raised if the abstract input cannot be represented +| exactly. However, if the abstract value is too large, the overflow and +| inexact exceptions are raised and an infinity or maximal finite value is +| returned. If the abstract value is too small, the input value is rounded to +| a subnormal number, and the underflow and inexact exceptions are raised if +| the abstract input cannot be represented exactly as a subnormal quadruple- +| precision floating-point number. +| The input significand must be normalized or smaller. If the input +| significand is not normalized, `zExp' must be 0; in that case, the result +| returned is a subnormal number, and it must not require rounding. In the +| usual case that the input significand is normalized, `zExp' must be 1 less +| than the ``true'' floating-point exponent. The handling of underflow and +| overflow follows the IEC/IEEE Standard for Binary Floating-Point Arithmetic. +*----------------------------------------------------------------------------*/ + +INLINE float128 + roundAndPackFloat128( + flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1, bits64 zSig2 ) +{ + int8 roundingMode; + flag roundNearestEven, increment, isTiny; + + roundingMode = float_rounding_mode; + roundNearestEven = ( roundingMode == float_round_nearest_even ); + increment = ( (sbits64) zSig2 < 0 ); + if ( ! roundNearestEven ) { + if ( roundingMode == float_round_to_zero ) { + increment = 0; + } + else { + if ( zSign ) { + increment = ( roundingMode == float_round_down ) && zSig2; + } + else { + increment = ( roundingMode == float_round_up ) && zSig2; + } + } + } + if ( 0x7FFD <= (bits32) zExp ) { + if ( ( 0x7FFD < zExp ) + || ( ( zExp == 0x7FFD ) + && eq128( + LIT64( 0x0001FFFFFFFFFFFF ), + LIT64( 0xFFFFFFFFFFFFFFFF ), + zSig0, + zSig1 + ) + && increment + ) + ) { + float_raise( float_flag_overflow | float_flag_inexact ); + if ( ( roundingMode == float_round_to_zero ) + || ( zSign && ( roundingMode == float_round_up ) ) + || ( ! zSign && ( roundingMode == float_round_down ) ) + ) { + return + packFloat128( + zSign, + 0x7FFE, + LIT64( 0x0000FFFFFFFFFFFF ), + LIT64( 0xFFFFFFFFFFFFFFFF ) + ); + } + return packFloat128( zSign, 0x7FFF, 0, 0 ); + } + if ( zExp < 0 ) { + isTiny = + ( float_detect_tininess == float_tininess_before_rounding ) + || ( zExp < -1 ) + || ! increment + || lt128( + zSig0, + zSig1, + LIT64( 0x0001FFFFFFFFFFFF ), + LIT64( 0xFFFFFFFFFFFFFFFF ) + ); + shift128ExtraRightJamming( + zSig0, zSig1, zSig2, - zExp, &zSig0, &zSig1, &zSig2 ); + zExp = 0; + if ( isTiny && zSig2 ) float_raise( float_flag_underflow ); + if ( roundNearestEven ) { + increment = ( (sbits64) zSig2 < 0 ); + } + else { + if ( zSign ) { + increment = ( roundingMode == float_round_down ) && zSig2; + } + else { + increment = ( roundingMode == float_round_up ) && zSig2; + } + } + } + } + if ( zSig2 ) float_exception_flags |= float_flag_inexact; + if ( increment ) { + add128( zSig0, zSig1, 0, 1, &zSig0, &zSig1 ); + zSig1 &= ~ ( ( zSig2 + zSig2 == 0 ) & roundNearestEven ); + } + else { + if ( ( zSig0 | zSig1 ) == 0 ) zExp = 0; + } + return packFloat128( zSign, zExp, zSig0, zSig1 ); + +} + +/*---------------------------------------------------------------------------- +| Takes an abstract floating-point value having sign `zSign', exponent `zExp', +| and significand formed by the concatenation of `zSig0' and `zSig1', and +| returns the proper quadruple-precision floating-point value corresponding +| to the abstract input. This routine is just like `roundAndPackFloat128' +| except that the input significand has fewer bits and does not have to be +| normalized. In all cases, `zExp' must be 1 less than the ``true'' floating- +| point exponent. +*----------------------------------------------------------------------------*/ + +INLINE float128 + normalizeRoundAndPackFloat128( + flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1 ) +{ + int8 shiftCount; + bits64 zSig2; + + if ( zSig0 == 0 ) { + zSig0 = zSig1; + zSig1 = 0; + zExp -= 64; + } + shiftCount = countLeadingZeros64( zSig0 ) - 15; + if ( 0 <= shiftCount ) { + zSig2 = 0; + shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 ); + } + else { + shift128ExtraRightJamming( + zSig0, zSig1, 0, - shiftCount, &zSig0, &zSig1, &zSig2 ); + } + zExp -= shiftCount; + return roundAndPackFloat128( zSign, zExp, zSig0, zSig1, zSig2 ); + +} +#endif |