| /* |
| * QEMU float support |
| * |
| * The code in this source file is derived from release 2a of the SoftFloat |
| * IEC/IEEE Floating-point Arithmetic Package. Those parts of the code (and |
| * some later contributions) are provided under that license, as detailed below. |
| * It has subsequently been modified by contributors to the QEMU Project, |
| * so some portions are provided under: |
| * the SoftFloat-2a license |
| * the BSD license |
| * GPL-v2-or-later |
| * |
| * Any future contributions to this file after December 1st 2014 will be |
| * taken to be licensed under the Softfloat-2a license unless specifically |
| * indicated otherwise. |
| */ |
| |
| /* |
| =============================================================================== |
| This C source file 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. |
| |
| =============================================================================== |
| */ |
| |
| /* BSD licensing: |
| * Copyright (c) 2006, Fabrice Bellard |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright notice, |
| * this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright notice, |
| * this list of conditions and the following disclaimer in the documentation |
| * and/or other materials provided with the distribution. |
| * |
| * 3. Neither the name of the copyright holder nor the names of its contributors |
| * may be used to endorse or promote products derived from this software without |
| * specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE |
| * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
| * THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| /* Portions of this work are licensed under the terms of the GNU GPL, |
| * version 2 or later. See the COPYING file in the top-level directory. |
| */ |
| |
| /* softfloat (and in particular the code in softfloat-specialize.h) is |
| * target-dependent and needs the TARGET_* macros. |
| */ |
| #include "qemu/osdep.h" |
| |
| #include "fpu/softfloat.h" |
| |
| /* We only need stdlib for abort() */ |
| |
| /*---------------------------------------------------------------------------- |
| | Primitive arithmetic functions, including multi-word arithmetic, and |
| | division and square root approximations. (Can be specialized to target if |
| | desired.) |
| *----------------------------------------------------------------------------*/ |
| #include "softfloat-macros.h" |
| |
| /*---------------------------------------------------------------------------- |
| | Functions and definitions to determine: (1) whether tininess for underflow |
| | is detected before or after rounding by default, (2) what (if anything) |
| | happens when exceptions are raised, (3) how signaling NaNs are distinguished |
| | from quiet NaNs, (4) the default generated quiet NaNs, and (5) how NaNs |
| | are propagated from function inputs to output. These details are target- |
| | specific. |
| *----------------------------------------------------------------------------*/ |
| #include "softfloat-specialize.h" |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the fraction bits of the half-precision floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline uint32_t extractFloat16Frac(float16 a) |
| { |
| return float16_val(a) & 0x3ff; |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the exponent bits of the half-precision floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline int extractFloat16Exp(float16 a) |
| { |
| return (float16_val(a) >> 10) & 0x1f; |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the sign bit of the single-precision floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline flag extractFloat16Sign(float16 a) |
| { |
| return float16_val(a)>>15; |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Takes a 64-bit fixed-point value `absZ' with binary point between bits 6 |
| | and 7, and returns the properly rounded 32-bit integer corresponding to the |
| | input. If `zSign' is 1, the input is negated before being converted to an |
| | integer. Bit 63 of `absZ' must be zero. Ordinarily, the fixed-point input |
| | is simply rounded to an integer, with the inexact exception raised if the |
| | input cannot be represented exactly as an integer. However, if the fixed- |
| | point input is too large, the invalid exception is raised and the largest |
| | positive or negative integer is returned. |
| *----------------------------------------------------------------------------*/ |
| |
| static int32_t roundAndPackInt32(flag zSign, uint64_t absZ, float_status *status) |
| { |
| int8_t roundingMode; |
| flag roundNearestEven; |
| int8_t roundIncrement, roundBits; |
| int32_t z; |
| |
| roundingMode = status->float_rounding_mode; |
| roundNearestEven = ( roundingMode == float_round_nearest_even ); |
| switch (roundingMode) { |
| case float_round_nearest_even: |
| case float_round_ties_away: |
| roundIncrement = 0x40; |
| break; |
| case float_round_to_zero: |
| roundIncrement = 0; |
| break; |
| case float_round_up: |
| roundIncrement = zSign ? 0 : 0x7f; |
| break; |
| case float_round_down: |
| roundIncrement = zSign ? 0x7f : 0; |
| break; |
| default: |
| abort(); |
| } |
| roundBits = absZ & 0x7F; |
| absZ = ( absZ + roundIncrement )>>7; |
| absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); |
| z = absZ; |
| if ( zSign ) z = - z; |
| if ( ( absZ>>32 ) || ( z && ( ( z < 0 ) ^ zSign ) ) ) { |
| float_raise(float_flag_invalid, status); |
| return zSign ? (int32_t) 0x80000000 : 0x7FFFFFFF; |
| } |
| if (roundBits) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| return z; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Takes the 128-bit fixed-point value formed by concatenating `absZ0' and |
| | `absZ1', with binary point between bits 63 and 64 (between the input words), |
| | and returns the properly rounded 64-bit integer corresponding to the input. |
| | If `zSign' is 1, the input is negated before being converted to an integer. |
| | Ordinarily, the fixed-point input is simply rounded to an integer, with |
| | the inexact exception raised if the input cannot be represented exactly as |
| | an integer. However, if the fixed-point input is too large, the invalid |
| | exception is raised and the largest positive or negative integer is |
| | returned. |
| *----------------------------------------------------------------------------*/ |
| |
| static int64_t roundAndPackInt64(flag zSign, uint64_t absZ0, uint64_t absZ1, |
| float_status *status) |
| { |
| int8_t roundingMode; |
| flag roundNearestEven, increment; |
| int64_t z; |
| |
| roundingMode = status->float_rounding_mode; |
| roundNearestEven = ( roundingMode == float_round_nearest_even ); |
| switch (roundingMode) { |
| case float_round_nearest_even: |
| case float_round_ties_away: |
| increment = ((int64_t) absZ1 < 0); |
| break; |
| case float_round_to_zero: |
| increment = 0; |
| break; |
| case float_round_up: |
| increment = !zSign && absZ1; |
| break; |
| case float_round_down: |
| increment = zSign && absZ1; |
| break; |
| default: |
| abort(); |
| } |
| if ( increment ) { |
| ++absZ0; |
| if ( absZ0 == 0 ) goto overflow; |
| absZ0 &= ~ ( ( (uint64_t) ( absZ1<<1 ) == 0 ) & roundNearestEven ); |
| } |
| z = absZ0; |
| if ( zSign ) z = - z; |
| if ( z && ( ( z < 0 ) ^ zSign ) ) { |
| overflow: |
| float_raise(float_flag_invalid, status); |
| return |
| zSign ? (int64_t) LIT64( 0x8000000000000000 ) |
| : LIT64( 0x7FFFFFFFFFFFFFFF ); |
| } |
| if (absZ1) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| return z; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Takes the 128-bit fixed-point value formed by concatenating `absZ0' and |
| | `absZ1', with binary point between bits 63 and 64 (between the input words), |
| | and returns the properly rounded 64-bit unsigned integer corresponding to the |
| | input. Ordinarily, the fixed-point input is simply rounded to an integer, |
| | with the inexact exception raised if the input cannot be represented exactly |
| | as an integer. However, if the fixed-point input is too large, the invalid |
| | exception is raised and the largest unsigned integer is returned. |
| *----------------------------------------------------------------------------*/ |
| |
| static int64_t roundAndPackUint64(flag zSign, uint64_t absZ0, |
| uint64_t absZ1, float_status *status) |
| { |
| int8_t roundingMode; |
| flag roundNearestEven, increment; |
| |
| roundingMode = status->float_rounding_mode; |
| roundNearestEven = (roundingMode == float_round_nearest_even); |
| switch (roundingMode) { |
| case float_round_nearest_even: |
| case float_round_ties_away: |
| increment = ((int64_t)absZ1 < 0); |
| break; |
| case float_round_to_zero: |
| increment = 0; |
| break; |
| case float_round_up: |
| increment = !zSign && absZ1; |
| break; |
| case float_round_down: |
| increment = zSign && absZ1; |
| break; |
| default: |
| abort(); |
| } |
| if (increment) { |
| ++absZ0; |
| if (absZ0 == 0) { |
| float_raise(float_flag_invalid, status); |
| return LIT64(0xFFFFFFFFFFFFFFFF); |
| } |
| absZ0 &= ~(((uint64_t)(absZ1<<1) == 0) & roundNearestEven); |
| } |
| |
| if (zSign && absZ0) { |
| float_raise(float_flag_invalid, status); |
| return 0; |
| } |
| |
| if (absZ1) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| return absZ0; |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the fraction bits of the single-precision floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline uint32_t extractFloat32Frac( float32 a ) |
| { |
| |
| return float32_val(a) & 0x007FFFFF; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the exponent bits of the single-precision floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline int extractFloat32Exp(float32 a) |
| { |
| |
| return ( float32_val(a)>>23 ) & 0xFF; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the sign bit of the single-precision floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline flag extractFloat32Sign( float32 a ) |
| { |
| |
| return float32_val(a)>>31; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | If `a' is denormal and we are in flush-to-zero mode then set the |
| | input-denormal exception and return zero. Otherwise just return the value. |
| *----------------------------------------------------------------------------*/ |
| float32 float32_squash_input_denormal(float32 a, float_status *status) |
| { |
| if (status->flush_inputs_to_zero) { |
| if (extractFloat32Exp(a) == 0 && extractFloat32Frac(a) != 0) { |
| float_raise(float_flag_input_denormal, status); |
| return make_float32(float32_val(a) & 0x80000000); |
| } |
| } |
| return a; |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Normalizes the subnormal single-precision floating-point value represented |
| | by the denormalized significand `aSig'. The normalized exponent and |
| | significand are stored at the locations pointed to by `zExpPtr' and |
| | `zSigPtr', respectively. |
| *----------------------------------------------------------------------------*/ |
| |
| static void |
| normalizeFloat32Subnormal(uint32_t aSig, int *zExpPtr, uint32_t *zSigPtr) |
| { |
| int8_t shiftCount; |
| |
| shiftCount = countLeadingZeros32( aSig ) - 8; |
| *zSigPtr = aSig<<shiftCount; |
| *zExpPtr = 1 - shiftCount; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Packs the sign `zSign', exponent `zExp', and significand `zSig' into a |
| | single-precision floating-point value, returning the result. After being |
| | shifted into the proper positions, the three fields are simply added |
| | together to form the result. This means that any integer portion of `zSig' |
| | 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 `zSig' is a complete, normalized |
| | significand. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline float32 packFloat32(flag zSign, int zExp, uint32_t zSig) |
| { |
| |
| return make_float32( |
| ( ( (uint32_t) zSign )<<31 ) + ( ( (uint32_t) zExp )<<23 ) + zSig); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Takes an abstract floating-point value having sign `zSign', exponent `zExp', |
| | and significand `zSig', and returns the proper single-precision floating- |
| | point value corresponding to the abstract input. Ordinarily, the abstract |
| | value is simply rounded and packed into the single-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 single- |
| | precision floating-point number. |
| | The input significand `zSig' has its binary point between bits 30 |
| | and 29, which is 7 bits to the left of the usual location. This shifted |
| | significand must be normalized or smaller. If `zSig' 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 `zSig' 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. |
| *----------------------------------------------------------------------------*/ |
| |
| static float32 roundAndPackFloat32(flag zSign, int zExp, uint32_t zSig, |
| float_status *status) |
| { |
| int8_t roundingMode; |
| flag roundNearestEven; |
| int8_t roundIncrement, roundBits; |
| flag isTiny; |
| |
| roundingMode = status->float_rounding_mode; |
| roundNearestEven = ( roundingMode == float_round_nearest_even ); |
| switch (roundingMode) { |
| case float_round_nearest_even: |
| case float_round_ties_away: |
| roundIncrement = 0x40; |
| break; |
| case float_round_to_zero: |
| roundIncrement = 0; |
| break; |
| case float_round_up: |
| roundIncrement = zSign ? 0 : 0x7f; |
| break; |
| case float_round_down: |
| roundIncrement = zSign ? 0x7f : 0; |
| break; |
| default: |
| abort(); |
| break; |
| } |
| roundBits = zSig & 0x7F; |
| if ( 0xFD <= (uint16_t) zExp ) { |
| if ( ( 0xFD < zExp ) |
| || ( ( zExp == 0xFD ) |
| && ( (int32_t) ( zSig + roundIncrement ) < 0 ) ) |
| ) { |
| float_raise(float_flag_overflow | float_flag_inexact, status); |
| return packFloat32( zSign, 0xFF, - ( roundIncrement == 0 )); |
| } |
| if ( zExp < 0 ) { |
| if (status->flush_to_zero) { |
| float_raise(float_flag_output_denormal, status); |
| return packFloat32(zSign, 0, 0); |
| } |
| isTiny = |
| (status->float_detect_tininess |
| == float_tininess_before_rounding) |
| || ( zExp < -1 ) |
| || ( zSig + roundIncrement < 0x80000000 ); |
| shift32RightJamming( zSig, - zExp, &zSig ); |
| zExp = 0; |
| roundBits = zSig & 0x7F; |
| if (isTiny && roundBits) { |
| float_raise(float_flag_underflow, status); |
| } |
| } |
| } |
| if (roundBits) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| zSig = ( zSig + roundIncrement )>>7; |
| zSig &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); |
| if ( zSig == 0 ) zExp = 0; |
| return packFloat32( zSign, zExp, zSig ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Takes an abstract floating-point value having sign `zSign', exponent `zExp', |
| | and significand `zSig', and returns the proper single-precision floating- |
| | point value corresponding to the abstract input. This routine is just like |
| | `roundAndPackFloat32' except that `zSig' does not have to be normalized. |
| | Bit 31 of `zSig' must be zero, and `zExp' must be 1 less than the ``true'' |
| | floating-point exponent. |
| *----------------------------------------------------------------------------*/ |
| |
| static float32 |
| normalizeRoundAndPackFloat32(flag zSign, int zExp, uint32_t zSig, |
| float_status *status) |
| { |
| int8_t shiftCount; |
| |
| shiftCount = countLeadingZeros32( zSig ) - 1; |
| return roundAndPackFloat32(zSign, zExp - shiftCount, zSig<<shiftCount, |
| status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the fraction bits of the double-precision floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline uint64_t extractFloat64Frac( float64 a ) |
| { |
| |
| return float64_val(a) & LIT64( 0x000FFFFFFFFFFFFF ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the exponent bits of the double-precision floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline int extractFloat64Exp(float64 a) |
| { |
| |
| return ( float64_val(a)>>52 ) & 0x7FF; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the sign bit of the double-precision floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline flag extractFloat64Sign( float64 a ) |
| { |
| |
| return float64_val(a)>>63; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | If `a' is denormal and we are in flush-to-zero mode then set the |
| | input-denormal exception and return zero. Otherwise just return the value. |
| *----------------------------------------------------------------------------*/ |
| float64 float64_squash_input_denormal(float64 a, float_status *status) |
| { |
| if (status->flush_inputs_to_zero) { |
| if (extractFloat64Exp(a) == 0 && extractFloat64Frac(a) != 0) { |
| float_raise(float_flag_input_denormal, status); |
| return make_float64(float64_val(a) & (1ULL << 63)); |
| } |
| } |
| return a; |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Normalizes the subnormal double-precision floating-point value represented |
| | by the denormalized significand `aSig'. The normalized exponent and |
| | significand are stored at the locations pointed to by `zExpPtr' and |
| | `zSigPtr', respectively. |
| *----------------------------------------------------------------------------*/ |
| |
| static void |
| normalizeFloat64Subnormal(uint64_t aSig, int *zExpPtr, uint64_t *zSigPtr) |
| { |
| int8_t shiftCount; |
| |
| shiftCount = countLeadingZeros64( aSig ) - 11; |
| *zSigPtr = aSig<<shiftCount; |
| *zExpPtr = 1 - shiftCount; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Packs the sign `zSign', exponent `zExp', and significand `zSig' into a |
| | double-precision floating-point value, returning the result. After being |
| | shifted into the proper positions, the three fields are simply added |
| | together to form the result. This means that any integer portion of `zSig' |
| | 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 `zSig' is a complete, normalized |
| | significand. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline float64 packFloat64(flag zSign, int zExp, uint64_t zSig) |
| { |
| |
| return make_float64( |
| ( ( (uint64_t) zSign )<<63 ) + ( ( (uint64_t) zExp )<<52 ) + zSig); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Takes an abstract floating-point value having sign `zSign', exponent `zExp', |
| | and significand `zSig', and returns the proper double-precision floating- |
| | point value corresponding to the abstract input. Ordinarily, the abstract |
| | value is simply rounded and packed into the double-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 double- |
| | precision floating-point number. |
| | The input significand `zSig' has its binary point between bits 62 |
| | and 61, which is 10 bits to the left of the usual location. This shifted |
| | significand must be normalized or smaller. If `zSig' 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 `zSig' 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. |
| *----------------------------------------------------------------------------*/ |
| |
| static float64 roundAndPackFloat64(flag zSign, int zExp, uint64_t zSig, |
| float_status *status) |
| { |
| int8_t roundingMode; |
| flag roundNearestEven; |
| int roundIncrement, roundBits; |
| flag isTiny; |
| |
| roundingMode = status->float_rounding_mode; |
| roundNearestEven = ( roundingMode == float_round_nearest_even ); |
| switch (roundingMode) { |
| case float_round_nearest_even: |
| case float_round_ties_away: |
| roundIncrement = 0x200; |
| break; |
| case float_round_to_zero: |
| roundIncrement = 0; |
| break; |
| case float_round_up: |
| roundIncrement = zSign ? 0 : 0x3ff; |
| break; |
| case float_round_down: |
| roundIncrement = zSign ? 0x3ff : 0; |
| break; |
| default: |
| abort(); |
| } |
| roundBits = zSig & 0x3FF; |
| if ( 0x7FD <= (uint16_t) zExp ) { |
| if ( ( 0x7FD < zExp ) |
| || ( ( zExp == 0x7FD ) |
| && ( (int64_t) ( zSig + roundIncrement ) < 0 ) ) |
| ) { |
| float_raise(float_flag_overflow | float_flag_inexact, status); |
| return packFloat64( zSign, 0x7FF, - ( roundIncrement == 0 )); |
| } |
| if ( zExp < 0 ) { |
| if (status->flush_to_zero) { |
| float_raise(float_flag_output_denormal, status); |
| return packFloat64(zSign, 0, 0); |
| } |
| isTiny = |
| (status->float_detect_tininess |
| == float_tininess_before_rounding) |
| || ( zExp < -1 ) |
| || ( zSig + roundIncrement < LIT64( 0x8000000000000000 ) ); |
| shift64RightJamming( zSig, - zExp, &zSig ); |
| zExp = 0; |
| roundBits = zSig & 0x3FF; |
| if (isTiny && roundBits) { |
| float_raise(float_flag_underflow, status); |
| } |
| } |
| } |
| if (roundBits) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| zSig = ( zSig + roundIncrement )>>10; |
| zSig &= ~ ( ( ( roundBits ^ 0x200 ) == 0 ) & roundNearestEven ); |
| if ( zSig == 0 ) zExp = 0; |
| return packFloat64( zSign, zExp, zSig ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Takes an abstract floating-point value having sign `zSign', exponent `zExp', |
| | and significand `zSig', and returns the proper double-precision floating- |
| | point value corresponding to the abstract input. This routine is just like |
| | `roundAndPackFloat64' except that `zSig' does not have to be normalized. |
| | Bit 63 of `zSig' must be zero, and `zExp' must be 1 less than the ``true'' |
| | floating-point exponent. |
| *----------------------------------------------------------------------------*/ |
| |
| static float64 |
| normalizeRoundAndPackFloat64(flag zSign, int zExp, uint64_t zSig, |
| float_status *status) |
| { |
| int8_t shiftCount; |
| |
| shiftCount = countLeadingZeros64( zSig ) - 1; |
| return roundAndPackFloat64(zSign, zExp - shiftCount, zSig<<shiftCount, |
| status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the fraction bits of the extended double-precision floating-point |
| | value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline uint64_t extractFloatx80Frac( floatx80 a ) |
| { |
| |
| return a.low; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the exponent bits of the extended double-precision floating-point |
| | value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline int32_t extractFloatx80Exp( floatx80 a ) |
| { |
| |
| return a.high & 0x7FFF; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the sign bit of the extended double-precision floating-point value |
| | `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline flag extractFloatx80Sign( floatx80 a ) |
| { |
| |
| return a.high>>15; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Normalizes the subnormal extended double-precision floating-point value |
| | represented by the denormalized significand `aSig'. The normalized exponent |
| | and significand are stored at the locations pointed to by `zExpPtr' and |
| | `zSigPtr', respectively. |
| *----------------------------------------------------------------------------*/ |
| |
| static void |
| normalizeFloatx80Subnormal( uint64_t aSig, int32_t *zExpPtr, uint64_t *zSigPtr ) |
| { |
| int8_t shiftCount; |
| |
| shiftCount = countLeadingZeros64( aSig ); |
| *zSigPtr = aSig<<shiftCount; |
| *zExpPtr = 1 - shiftCount; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Packs the sign `zSign', exponent `zExp', and significand `zSig' into an |
| | extended double-precision floating-point value, returning the result. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline floatx80 packFloatx80( flag zSign, int32_t zExp, uint64_t zSig ) |
| { |
| floatx80 z; |
| |
| z.low = zSig; |
| z.high = ( ( (uint16_t) zSign )<<15 ) + zExp; |
| return z; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Takes an abstract floating-point value having sign `zSign', exponent `zExp', |
| | and extended significand formed by the concatenation of `zSig0' and `zSig1', |
| | and returns the proper extended double-precision floating-point value |
| | corresponding to the abstract input. Ordinarily, the abstract value is |
| | rounded and packed into the extended double-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 extended |
| | double-precision floating-point number. |
| | If `roundingPrecision' is 32 or 64, the result is rounded to the same |
| | number of bits as single or double precision, respectively. Otherwise, the |
| | result is rounded to the full precision of the extended double-precision |
| | format. |
| | 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. The |
| | handling of underflow and overflow follows the IEC/IEEE Standard for Binary |
| | Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| static floatx80 roundAndPackFloatx80(int8_t roundingPrecision, flag zSign, |
| int32_t zExp, uint64_t zSig0, uint64_t zSig1, |
| float_status *status) |
| { |
| int8_t roundingMode; |
| flag roundNearestEven, increment, isTiny; |
| int64_t roundIncrement, roundMask, roundBits; |
| |
| roundingMode = status->float_rounding_mode; |
| roundNearestEven = ( roundingMode == float_round_nearest_even ); |
| if ( roundingPrecision == 80 ) goto precision80; |
| if ( roundingPrecision == 64 ) { |
| roundIncrement = LIT64( 0x0000000000000400 ); |
| roundMask = LIT64( 0x00000000000007FF ); |
| } |
| else if ( roundingPrecision == 32 ) { |
| roundIncrement = LIT64( 0x0000008000000000 ); |
| roundMask = LIT64( 0x000000FFFFFFFFFF ); |
| } |
| else { |
| goto precision80; |
| } |
| zSig0 |= ( zSig1 != 0 ); |
| switch (roundingMode) { |
| case float_round_nearest_even: |
| case float_round_ties_away: |
| break; |
| case float_round_to_zero: |
| roundIncrement = 0; |
| break; |
| case float_round_up: |
| roundIncrement = zSign ? 0 : roundMask; |
| break; |
| case float_round_down: |
| roundIncrement = zSign ? roundMask : 0; |
| break; |
| default: |
| abort(); |
| } |
| roundBits = zSig0 & roundMask; |
| if ( 0x7FFD <= (uint32_t) ( zExp - 1 ) ) { |
| if ( ( 0x7FFE < zExp ) |
| || ( ( zExp == 0x7FFE ) && ( zSig0 + roundIncrement < zSig0 ) ) |
| ) { |
| goto overflow; |
| } |
| if ( zExp <= 0 ) { |
| if (status->flush_to_zero) { |
| float_raise(float_flag_output_denormal, status); |
| return packFloatx80(zSign, 0, 0); |
| } |
| isTiny = |
| (status->float_detect_tininess |
| == float_tininess_before_rounding) |
| || ( zExp < 0 ) |
| || ( zSig0 <= zSig0 + roundIncrement ); |
| shift64RightJamming( zSig0, 1 - zExp, &zSig0 ); |
| zExp = 0; |
| roundBits = zSig0 & roundMask; |
| if (isTiny && roundBits) { |
| float_raise(float_flag_underflow, status); |
| } |
| if (roundBits) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| zSig0 += roundIncrement; |
| if ( (int64_t) zSig0 < 0 ) zExp = 1; |
| roundIncrement = roundMask + 1; |
| if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) { |
| roundMask |= roundIncrement; |
| } |
| zSig0 &= ~ roundMask; |
| return packFloatx80( zSign, zExp, zSig0 ); |
| } |
| } |
| if (roundBits) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| zSig0 += roundIncrement; |
| if ( zSig0 < roundIncrement ) { |
| ++zExp; |
| zSig0 = LIT64( 0x8000000000000000 ); |
| } |
| roundIncrement = roundMask + 1; |
| if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) { |
| roundMask |= roundIncrement; |
| } |
| zSig0 &= ~ roundMask; |
| if ( zSig0 == 0 ) zExp = 0; |
| return packFloatx80( zSign, zExp, zSig0 ); |
| precision80: |
| switch (roundingMode) { |
| case float_round_nearest_even: |
| case float_round_ties_away: |
| increment = ((int64_t)zSig1 < 0); |
| break; |
| case float_round_to_zero: |
| increment = 0; |
| break; |
| case float_round_up: |
| increment = !zSign && zSig1; |
| break; |
| case float_round_down: |
| increment = zSign && zSig1; |
| break; |
| default: |
| abort(); |
| } |
| if ( 0x7FFD <= (uint32_t) ( zExp - 1 ) ) { |
| if ( ( 0x7FFE < zExp ) |
| || ( ( zExp == 0x7FFE ) |
| && ( zSig0 == LIT64( 0xFFFFFFFFFFFFFFFF ) ) |
| && increment |
| ) |
| ) { |
| roundMask = 0; |
| overflow: |
| float_raise(float_flag_overflow | float_flag_inexact, status); |
| if ( ( roundingMode == float_round_to_zero ) |
| || ( zSign && ( roundingMode == float_round_up ) ) |
| || ( ! zSign && ( roundingMode == float_round_down ) ) |
| ) { |
| return packFloatx80( zSign, 0x7FFE, ~ roundMask ); |
| } |
| return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| } |
| if ( zExp <= 0 ) { |
| isTiny = |
| (status->float_detect_tininess |
| == float_tininess_before_rounding) |
| || ( zExp < 0 ) |
| || ! increment |
| || ( zSig0 < LIT64( 0xFFFFFFFFFFFFFFFF ) ); |
| shift64ExtraRightJamming( zSig0, zSig1, 1 - zExp, &zSig0, &zSig1 ); |
| zExp = 0; |
| if (isTiny && zSig1) { |
| float_raise(float_flag_underflow, status); |
| } |
| if (zSig1) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| switch (roundingMode) { |
| case float_round_nearest_even: |
| case float_round_ties_away: |
| increment = ((int64_t)zSig1 < 0); |
| break; |
| case float_round_to_zero: |
| increment = 0; |
| break; |
| case float_round_up: |
| increment = !zSign && zSig1; |
| break; |
| case float_round_down: |
| increment = zSign && zSig1; |
| break; |
| default: |
| abort(); |
| } |
| if ( increment ) { |
| ++zSig0; |
| zSig0 &= |
| ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); |
| if ( (int64_t) zSig0 < 0 ) zExp = 1; |
| } |
| return packFloatx80( zSign, zExp, zSig0 ); |
| } |
| } |
| if (zSig1) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| if ( increment ) { |
| ++zSig0; |
| if ( zSig0 == 0 ) { |
| ++zExp; |
| zSig0 = LIT64( 0x8000000000000000 ); |
| } |
| else { |
| zSig0 &= ~ ( ( (uint64_t) ( zSig1<<1 ) == 0 ) & roundNearestEven ); |
| } |
| } |
| else { |
| if ( zSig0 == 0 ) zExp = 0; |
| } |
| return packFloatx80( zSign, zExp, zSig0 ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | 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 extended double-precision floating-point value |
| | corresponding to the abstract input. This routine is just like |
| | `roundAndPackFloatx80' except that the input significand does not have to be |
| | normalized. |
| *----------------------------------------------------------------------------*/ |
| |
| static floatx80 normalizeRoundAndPackFloatx80(int8_t roundingPrecision, |
| flag zSign, int32_t zExp, |
| uint64_t zSig0, uint64_t zSig1, |
| float_status *status) |
| { |
| int8_t shiftCount; |
| |
| if ( zSig0 == 0 ) { |
| zSig0 = zSig1; |
| zSig1 = 0; |
| zExp -= 64; |
| } |
| shiftCount = countLeadingZeros64( zSig0 ); |
| shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 ); |
| zExp -= shiftCount; |
| return roundAndPackFloatx80(roundingPrecision, zSign, zExp, |
| zSig0, zSig1, status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the least-significant 64 fraction bits of the quadruple-precision |
| | floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline uint64_t extractFloat128Frac1( float128 a ) |
| { |
| |
| return a.low; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the most-significant 48 fraction bits of the quadruple-precision |
| | floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline uint64_t extractFloat128Frac0( float128 a ) |
| { |
| |
| return a.high & LIT64( 0x0000FFFFFFFFFFFF ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the exponent bits of the quadruple-precision floating-point value |
| | `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline int32_t extractFloat128Exp( float128 a ) |
| { |
| |
| return ( a.high>>48 ) & 0x7FFF; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the sign bit of the quadruple-precision floating-point value `a'. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline flag extractFloat128Sign( float128 a ) |
| { |
| |
| return a.high>>63; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Normalizes the subnormal quadruple-precision floating-point value |
| | represented by the denormalized significand formed by the concatenation of |
| | `aSig0' and `aSig1'. The normalized exponent is stored at the location |
| | pointed to by `zExpPtr'. The most significant 49 bits of the normalized |
| | significand are stored at the location pointed to by `zSig0Ptr', and the |
| | least significant 64 bits of the normalized significand are stored at the |
| | location pointed to by `zSig1Ptr'. |
| *----------------------------------------------------------------------------*/ |
| |
| static void |
| normalizeFloat128Subnormal( |
| uint64_t aSig0, |
| uint64_t aSig1, |
| int32_t *zExpPtr, |
| uint64_t *zSig0Ptr, |
| uint64_t *zSig1Ptr |
| ) |
| { |
| int8_t shiftCount; |
| |
| if ( aSig0 == 0 ) { |
| shiftCount = countLeadingZeros64( aSig1 ) - 15; |
| if ( shiftCount < 0 ) { |
| *zSig0Ptr = aSig1>>( - shiftCount ); |
| *zSig1Ptr = aSig1<<( shiftCount & 63 ); |
| } |
| else { |
| *zSig0Ptr = aSig1<<shiftCount; |
| *zSig1Ptr = 0; |
| } |
| *zExpPtr = - shiftCount - 63; |
| } |
| else { |
| shiftCount = countLeadingZeros64( aSig0 ) - 15; |
| shortShift128Left( aSig0, aSig1, shiftCount, zSig0Ptr, zSig1Ptr ); |
| *zExpPtr = 1 - shiftCount; |
| } |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | 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. |
| *----------------------------------------------------------------------------*/ |
| |
| static inline float128 |
| packFloat128( flag zSign, int32_t zExp, uint64_t zSig0, uint64_t zSig1 ) |
| { |
| float128 z; |
| |
| z.low = zSig1; |
| z.high = ( ( (uint64_t) zSign )<<63 ) + ( ( (uint64_t) 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. |
| *----------------------------------------------------------------------------*/ |
| |
| static float128 roundAndPackFloat128(flag zSign, int32_t zExp, |
| uint64_t zSig0, uint64_t zSig1, |
| uint64_t zSig2, float_status *status) |
| { |
| int8_t roundingMode; |
| flag roundNearestEven, increment, isTiny; |
| |
| roundingMode = status->float_rounding_mode; |
| roundNearestEven = ( roundingMode == float_round_nearest_even ); |
| switch (roundingMode) { |
| case float_round_nearest_even: |
| case float_round_ties_away: |
| increment = ((int64_t)zSig2 < 0); |
| break; |
| case float_round_to_zero: |
| increment = 0; |
| break; |
| case float_round_up: |
| increment = !zSign && zSig2; |
| break; |
| case float_round_down: |
| increment = zSign && zSig2; |
| break; |
| default: |
| abort(); |
| } |
| if ( 0x7FFD <= (uint32_t) zExp ) { |
| if ( ( 0x7FFD < zExp ) |
| || ( ( zExp == 0x7FFD ) |
| && eq128( |
| LIT64( 0x0001FFFFFFFFFFFF ), |
| LIT64( 0xFFFFFFFFFFFFFFFF ), |
| zSig0, |
| zSig1 |
| ) |
| && increment |
| ) |
| ) { |
| float_raise(float_flag_overflow | float_flag_inexact, status); |
| 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 ) { |
| if (status->flush_to_zero) { |
| float_raise(float_flag_output_denormal, status); |
| return packFloat128(zSign, 0, 0, 0); |
| } |
| isTiny = |
| (status->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, status); |
| } |
| switch (roundingMode) { |
| case float_round_nearest_even: |
| case float_round_ties_away: |
| increment = ((int64_t)zSig2 < 0); |
| break; |
| case float_round_to_zero: |
| increment = 0; |
| break; |
| case float_round_up: |
| increment = !zSign && zSig2; |
| break; |
| case float_round_down: |
| increment = zSign && zSig2; |
| break; |
| default: |
| abort(); |
| } |
| } |
| } |
| if (zSig2) { |
| status->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. |
| *----------------------------------------------------------------------------*/ |
| |
| static float128 normalizeRoundAndPackFloat128(flag zSign, int32_t zExp, |
| uint64_t zSig0, uint64_t zSig1, |
| float_status *status) |
| { |
| int8_t shiftCount; |
| uint64_t 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, status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 32-bit two's complement integer `a' |
| | to the single-precision floating-point format. The conversion is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float32 int32_to_float32(int32_t a, float_status *status) |
| { |
| flag zSign; |
| |
| if ( a == 0 ) return float32_zero; |
| if ( a == (int32_t) 0x80000000 ) return packFloat32( 1, 0x9E, 0 ); |
| zSign = ( a < 0 ); |
| return normalizeRoundAndPackFloat32(zSign, 0x9C, zSign ? -a : a, status); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 32-bit two's complement integer `a' |
| | to the double-precision floating-point format. The conversion is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float64 int32_to_float64(int32_t a, float_status *status) |
| { |
| flag zSign; |
| uint32_t absA; |
| int8_t shiftCount; |
| uint64_t zSig; |
| |
| if ( a == 0 ) return float64_zero; |
| zSign = ( a < 0 ); |
| absA = zSign ? - a : a; |
| shiftCount = countLeadingZeros32( absA ) + 21; |
| zSig = absA; |
| return packFloat64( zSign, 0x432 - shiftCount, zSig<<shiftCount ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 32-bit two's complement integer `a' |
| | to the extended double-precision floating-point format. The conversion |
| | is performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| floatx80 int32_to_floatx80(int32_t a, float_status *status) |
| { |
| flag zSign; |
| uint32_t absA; |
| int8_t shiftCount; |
| uint64_t zSig; |
| |
| if ( a == 0 ) return packFloatx80( 0, 0, 0 ); |
| zSign = ( a < 0 ); |
| absA = zSign ? - a : a; |
| shiftCount = countLeadingZeros32( absA ) + 32; |
| zSig = absA; |
| return packFloatx80( zSign, 0x403E - shiftCount, zSig<<shiftCount ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 32-bit two's complement integer `a' to |
| | the quadruple-precision floating-point format. The conversion is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float128 int32_to_float128(int32_t a, float_status *status) |
| { |
| flag zSign; |
| uint32_t absA; |
| int8_t shiftCount; |
| uint64_t zSig0; |
| |
| if ( a == 0 ) return packFloat128( 0, 0, 0, 0 ); |
| zSign = ( a < 0 ); |
| absA = zSign ? - a : a; |
| shiftCount = countLeadingZeros32( absA ) + 17; |
| zSig0 = absA; |
| return packFloat128( zSign, 0x402E - shiftCount, zSig0<<shiftCount, 0 ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 64-bit two's complement integer `a' |
| | to the single-precision floating-point format. The conversion is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float32 int64_to_float32(int64_t a, float_status *status) |
| { |
| flag zSign; |
| uint64_t absA; |
| int8_t shiftCount; |
| |
| if ( a == 0 ) return float32_zero; |
| zSign = ( a < 0 ); |
| absA = zSign ? - a : a; |
| shiftCount = countLeadingZeros64( absA ) - 40; |
| if ( 0 <= shiftCount ) { |
| return packFloat32( zSign, 0x95 - shiftCount, absA<<shiftCount ); |
| } |
| else { |
| shiftCount += 7; |
| if ( shiftCount < 0 ) { |
| shift64RightJamming( absA, - shiftCount, &absA ); |
| } |
| else { |
| absA <<= shiftCount; |
| } |
| return roundAndPackFloat32(zSign, 0x9C - shiftCount, absA, status); |
| } |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 64-bit two's complement integer `a' |
| | to the double-precision floating-point format. The conversion is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float64 int64_to_float64(int64_t a, float_status *status) |
| { |
| flag zSign; |
| |
| if ( a == 0 ) return float64_zero; |
| if ( a == (int64_t) LIT64( 0x8000000000000000 ) ) { |
| return packFloat64( 1, 0x43E, 0 ); |
| } |
| zSign = ( a < 0 ); |
| return normalizeRoundAndPackFloat64(zSign, 0x43C, zSign ? -a : a, status); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 64-bit two's complement integer `a' |
| | to the extended double-precision floating-point format. The conversion |
| | is performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| floatx80 int64_to_floatx80(int64_t a, float_status *status) |
| { |
| flag zSign; |
| uint64_t absA; |
| int8_t shiftCount; |
| |
| if ( a == 0 ) return packFloatx80( 0, 0, 0 ); |
| zSign = ( a < 0 ); |
| absA = zSign ? - a : a; |
| shiftCount = countLeadingZeros64( absA ); |
| return packFloatx80( zSign, 0x403E - shiftCount, absA<<shiftCount ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 64-bit two's complement integer `a' to |
| | the quadruple-precision floating-point format. The conversion is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float128 int64_to_float128(int64_t a, float_status *status) |
| { |
| flag zSign; |
| uint64_t absA; |
| int8_t shiftCount; |
| int32_t zExp; |
| uint64_t zSig0, zSig1; |
| |
| if ( a == 0 ) return packFloat128( 0, 0, 0, 0 ); |
| zSign = ( a < 0 ); |
| absA = zSign ? - a : a; |
| shiftCount = countLeadingZeros64( absA ) + 49; |
| zExp = 0x406E - shiftCount; |
| if ( 64 <= shiftCount ) { |
| zSig1 = 0; |
| zSig0 = absA; |
| shiftCount -= 64; |
| } |
| else { |
| zSig1 = absA; |
| zSig0 = 0; |
| } |
| shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 ); |
| return packFloat128( zSign, zExp, zSig0, zSig1 ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 64-bit unsigned integer `a' |
| | to the single-precision floating-point format. The conversion is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float32 uint64_to_float32(uint64_t a, float_status *status) |
| { |
| int shiftcount; |
| |
| if (a == 0) { |
| return float32_zero; |
| } |
| |
| /* Determine (left) shift needed to put first set bit into bit posn 23 |
| * (since packFloat32() expects the binary point between bits 23 and 22); |
| * this is the fast case for smallish numbers. |
| */ |
| shiftcount = countLeadingZeros64(a) - 40; |
| if (shiftcount >= 0) { |
| return packFloat32(0, 0x95 - shiftcount, a << shiftcount); |
| } |
| /* Otherwise we need to do a round-and-pack. roundAndPackFloat32() |
| * expects the binary point between bits 30 and 29, hence the + 7. |
| */ |
| shiftcount += 7; |
| if (shiftcount < 0) { |
| shift64RightJamming(a, -shiftcount, &a); |
| } else { |
| a <<= shiftcount; |
| } |
| |
| return roundAndPackFloat32(0, 0x9c - shiftcount, a, status); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 64-bit unsigned integer `a' |
| | to the double-precision floating-point format. The conversion is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float64 uint64_to_float64(uint64_t a, float_status *status) |
| { |
| int exp = 0x43C; |
| int shiftcount; |
| |
| if (a == 0) { |
| return float64_zero; |
| } |
| |
| shiftcount = countLeadingZeros64(a) - 1; |
| if (shiftcount < 0) { |
| shift64RightJamming(a, -shiftcount, &a); |
| } else { |
| a <<= shiftcount; |
| } |
| return roundAndPackFloat64(0, exp - shiftcount, a, status); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the 64-bit unsigned integer `a' |
| | to the quadruple-precision floating-point format. The conversion is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float128 uint64_to_float128(uint64_t a, float_status *status) |
| { |
| if (a == 0) { |
| return float128_zero; |
| } |
| return normalizeRoundAndPackFloat128(0, 0x406E, a, 0, status); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the single-precision floating-point value |
| | `a' to the 32-bit two's complement integer format. The conversion is |
| | performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic---which means in particular that the conversion is rounded |
| | according to the current rounding mode. If `a' is a NaN, the largest |
| | positive integer is returned. Otherwise, if the conversion overflows, the |
| | largest integer with the same sign as `a' is returned. |
| *----------------------------------------------------------------------------*/ |
| |
| int32_t float32_to_int32(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| int shiftCount; |
| uint32_t aSig; |
| uint64_t aSig64; |
| |
| a = float32_squash_input_denormal(a, status); |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| if ( ( aExp == 0xFF ) && aSig ) aSign = 0; |
| if ( aExp ) aSig |= 0x00800000; |
| shiftCount = 0xAF - aExp; |
| aSig64 = aSig; |
| aSig64 <<= 32; |
| if ( 0 < shiftCount ) shift64RightJamming( aSig64, shiftCount, &aSig64 ); |
| return roundAndPackInt32(aSign, aSig64, status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the single-precision floating-point value |
| | `a' to the 32-bit two's complement integer format. The conversion is |
| | performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic, except that the conversion is always rounded toward zero. |
| | If `a' is a NaN, the largest positive integer is returned. Otherwise, if |
| | the conversion overflows, the largest integer with the same sign as `a' is |
| | returned. |
| *----------------------------------------------------------------------------*/ |
| |
| int32_t float32_to_int32_round_to_zero(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| int shiftCount; |
| uint32_t aSig; |
| int32_t z; |
| a = float32_squash_input_denormal(a, status); |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| shiftCount = aExp - 0x9E; |
| if ( 0 <= shiftCount ) { |
| if ( float32_val(a) != 0xCF000000 ) { |
| float_raise(float_flag_invalid, status); |
| if ( ! aSign || ( ( aExp == 0xFF ) && aSig ) ) return 0x7FFFFFFF; |
| } |
| return (int32_t) 0x80000000; |
| } |
| else if ( aExp <= 0x7E ) { |
| if (aExp | aSig) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| return 0; |
| } |
| aSig = ( aSig | 0x00800000 )<<8; |
| z = aSig>>( - shiftCount ); |
| if ( (uint32_t) ( aSig<<( shiftCount & 31 ) ) ) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| if ( aSign ) z = - z; |
| return z; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the single-precision floating-point value |
| | `a' to the 16-bit two's complement integer format. The conversion is |
| | performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic, except that the conversion is always rounded toward zero. |
| | If `a' is a NaN, the largest positive integer is returned. Otherwise, if |
| | the conversion overflows, the largest integer with the same sign as `a' is |
| | returned. |
| *----------------------------------------------------------------------------*/ |
| |
| int16_t float32_to_int16_round_to_zero(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| int shiftCount; |
| uint32_t aSig; |
| int32_t z; |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| shiftCount = aExp - 0x8E; |
| if ( 0 <= shiftCount ) { |
| if ( float32_val(a) != 0xC7000000 ) { |
| float_raise(float_flag_invalid, status); |
| if ( ! aSign || ( ( aExp == 0xFF ) && aSig ) ) { |
| return 0x7FFF; |
| } |
| } |
| return (int32_t) 0xffff8000; |
| } |
| else if ( aExp <= 0x7E ) { |
| if ( aExp | aSig ) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| return 0; |
| } |
| shiftCount -= 0x10; |
| aSig = ( aSig | 0x00800000 )<<8; |
| z = aSig>>( - shiftCount ); |
| if ( (uint32_t) ( aSig<<( shiftCount & 31 ) ) ) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| if ( aSign ) { |
| z = - z; |
| } |
| return z; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the single-precision floating-point value |
| | `a' to the 64-bit two's complement integer format. The conversion is |
| | performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic---which means in particular that the conversion is rounded |
| | according to the current rounding mode. If `a' is a NaN, the largest |
| | positive integer is returned. Otherwise, if the conversion overflows, the |
| | largest integer with the same sign as `a' is returned. |
| *----------------------------------------------------------------------------*/ |
| |
| int64_t float32_to_int64(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| int shiftCount; |
| uint32_t aSig; |
| uint64_t aSig64, aSigExtra; |
| a = float32_squash_input_denormal(a, status); |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| shiftCount = 0xBE - aExp; |
| if ( shiftCount < 0 ) { |
| float_raise(float_flag_invalid, status); |
| if ( ! aSign || ( ( aExp == 0xFF ) && aSig ) ) { |
| return LIT64( 0x7FFFFFFFFFFFFFFF ); |
| } |
| return (int64_t) LIT64( 0x8000000000000000 ); |
| } |
| if ( aExp ) aSig |= 0x00800000; |
| aSig64 = aSig; |
| aSig64 <<= 40; |
| shift64ExtraRightJamming( aSig64, 0, shiftCount, &aSig64, &aSigExtra ); |
| return roundAndPackInt64(aSign, aSig64, aSigExtra, status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the single-precision floating-point value |
| | `a' to the 64-bit unsigned integer format. The conversion is |
| | performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic---which means in particular that the conversion is rounded |
| | according to the current rounding mode. If `a' is a NaN, the largest |
| | unsigned integer is returned. Otherwise, if the conversion overflows, the |
| | largest unsigned integer is returned. If the 'a' is negative, the result |
| | is rounded and zero is returned; values that do not round to zero will |
| | raise the inexact exception flag. |
| *----------------------------------------------------------------------------*/ |
| |
| uint64_t float32_to_uint64(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| int shiftCount; |
| uint32_t aSig; |
| uint64_t aSig64, aSigExtra; |
| a = float32_squash_input_denormal(a, status); |
| |
| aSig = extractFloat32Frac(a); |
| aExp = extractFloat32Exp(a); |
| aSign = extractFloat32Sign(a); |
| if ((aSign) && (aExp > 126)) { |
| float_raise(float_flag_invalid, status); |
| if (float32_is_any_nan(a)) { |
| return LIT64(0xFFFFFFFFFFFFFFFF); |
| } else { |
| return 0; |
| } |
| } |
| shiftCount = 0xBE - aExp; |
| if (aExp) { |
| aSig |= 0x00800000; |
| } |
| if (shiftCount < 0) { |
| float_raise(float_flag_invalid, status); |
| return LIT64(0xFFFFFFFFFFFFFFFF); |
| } |
| |
| aSig64 = aSig; |
| aSig64 <<= 40; |
| shift64ExtraRightJamming(aSig64, 0, shiftCount, &aSig64, &aSigExtra); |
| return roundAndPackUint64(aSign, aSig64, aSigExtra, status); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the single-precision floating-point value |
| | `a' to the 64-bit unsigned integer format. The conversion is |
| | performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic, except that the conversion is always rounded toward zero. If |
| | `a' is a NaN, the largest unsigned integer is returned. Otherwise, if the |
| | conversion overflows, the largest unsigned integer is returned. If the |
| | 'a' is negative, the result is rounded and zero is returned; values that do |
| | not round to zero will raise the inexact flag. |
| *----------------------------------------------------------------------------*/ |
| |
| uint64_t float32_to_uint64_round_to_zero(float32 a, float_status *status) |
| { |
| signed char current_rounding_mode = status->float_rounding_mode; |
| set_float_rounding_mode(float_round_to_zero, status); |
| int64_t v = float32_to_uint64(a, status); |
| set_float_rounding_mode(current_rounding_mode, status); |
| return v; |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the single-precision floating-point value |
| | `a' to the 64-bit two's complement integer format. The conversion is |
| | performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic, except that the conversion is always rounded toward zero. If |
| | `a' is a NaN, the largest positive integer is returned. Otherwise, if the |
| | conversion overflows, the largest integer with the same sign as `a' is |
| | returned. |
| *----------------------------------------------------------------------------*/ |
| |
| int64_t float32_to_int64_round_to_zero(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| int shiftCount; |
| uint32_t aSig; |
| uint64_t aSig64; |
| int64_t z; |
| a = float32_squash_input_denormal(a, status); |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| shiftCount = aExp - 0xBE; |
| if ( 0 <= shiftCount ) { |
| if ( float32_val(a) != 0xDF000000 ) { |
| float_raise(float_flag_invalid, status); |
| if ( ! aSign || ( ( aExp == 0xFF ) && aSig ) ) { |
| return LIT64( 0x7FFFFFFFFFFFFFFF ); |
| } |
| } |
| return (int64_t) LIT64( 0x8000000000000000 ); |
| } |
| else if ( aExp <= 0x7E ) { |
| if (aExp | aSig) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| return 0; |
| } |
| aSig64 = aSig | 0x00800000; |
| aSig64 <<= 40; |
| z = aSig64>>( - shiftCount ); |
| if ( (uint64_t) ( aSig64<<( shiftCount & 63 ) ) ) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| if ( aSign ) z = - z; |
| return z; |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the single-precision floating-point value |
| | `a' to the double-precision floating-point format. The conversion is |
| | performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float64 float32_to_float64(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| uint32_t aSig; |
| a = float32_squash_input_denormal(a, status); |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| if ( aExp == 0xFF ) { |
| if (aSig) { |
| return commonNaNToFloat64(float32ToCommonNaN(a, status), status); |
| } |
| return packFloat64( aSign, 0x7FF, 0 ); |
| } |
| if ( aExp == 0 ) { |
| if ( aSig == 0 ) return packFloat64( aSign, 0, 0 ); |
| normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| --aExp; |
| } |
| return packFloat64( aSign, aExp + 0x380, ( (uint64_t) aSig )<<29 ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the single-precision floating-point value |
| | `a' to the extended double-precision floating-point format. The conversion |
| | is performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| floatx80 float32_to_floatx80(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| uint32_t aSig; |
| |
| a = float32_squash_input_denormal(a, status); |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| if ( aExp == 0xFF ) { |
| if (aSig) { |
| return commonNaNToFloatx80(float32ToCommonNaN(a, status), status); |
| } |
| return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| } |
| if ( aExp == 0 ) { |
| if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 ); |
| normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| } |
| aSig |= 0x00800000; |
| return packFloatx80( aSign, aExp + 0x3F80, ( (uint64_t) aSig )<<40 ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of converting the single-precision floating-point value |
| | `a' to the double-precision floating-point format. The conversion is |
| | performed according to the IEC/IEEE Standard for Binary Floating-Point |
| | Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float128 float32_to_float128(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| uint32_t aSig; |
| |
| a = float32_squash_input_denormal(a, status); |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| if ( aExp == 0xFF ) { |
| if (aSig) { |
| return commonNaNToFloat128(float32ToCommonNaN(a, status), status); |
| } |
| return packFloat128( aSign, 0x7FFF, 0, 0 ); |
| } |
| if ( aExp == 0 ) { |
| if ( aSig == 0 ) return packFloat128( aSign, 0, 0, 0 ); |
| normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| --aExp; |
| } |
| return packFloat128( aSign, aExp + 0x3F80, ( (uint64_t) aSig )<<25, 0 ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Rounds the single-precision floating-point value `a' to an integer, and |
| | returns the result as a single-precision floating-point value. The |
| | operation is performed according to the IEC/IEEE Standard for Binary |
| | Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float32 float32_round_to_int(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| uint32_t lastBitMask, roundBitsMask; |
| uint32_t z; |
| a = float32_squash_input_denormal(a, status); |
| |
| aExp = extractFloat32Exp( a ); |
| if ( 0x96 <= aExp ) { |
| if ( ( aExp == 0xFF ) && extractFloat32Frac( a ) ) { |
| return propagateFloat32NaN(a, a, status); |
| } |
| return a; |
| } |
| if ( aExp <= 0x7E ) { |
| if ( (uint32_t) ( float32_val(a)<<1 ) == 0 ) return a; |
| status->float_exception_flags |= float_flag_inexact; |
| aSign = extractFloat32Sign( a ); |
| switch (status->float_rounding_mode) { |
| case float_round_nearest_even: |
| if ( ( aExp == 0x7E ) && extractFloat32Frac( a ) ) { |
| return packFloat32( aSign, 0x7F, 0 ); |
| } |
| break; |
| case float_round_ties_away: |
| if (aExp == 0x7E) { |
| return packFloat32(aSign, 0x7F, 0); |
| } |
| break; |
| case float_round_down: |
| return make_float32(aSign ? 0xBF800000 : 0); |
| case float_round_up: |
| return make_float32(aSign ? 0x80000000 : 0x3F800000); |
| } |
| return packFloat32( aSign, 0, 0 ); |
| } |
| lastBitMask = 1; |
| lastBitMask <<= 0x96 - aExp; |
| roundBitsMask = lastBitMask - 1; |
| z = float32_val(a); |
| switch (status->float_rounding_mode) { |
| case float_round_nearest_even: |
| z += lastBitMask>>1; |
| if ((z & roundBitsMask) == 0) { |
| z &= ~lastBitMask; |
| } |
| break; |
| case float_round_ties_away: |
| z += lastBitMask >> 1; |
| break; |
| case float_round_to_zero: |
| break; |
| case float_round_up: |
| if (!extractFloat32Sign(make_float32(z))) { |
| z += roundBitsMask; |
| } |
| break; |
| case float_round_down: |
| if (extractFloat32Sign(make_float32(z))) { |
| z += roundBitsMask; |
| } |
| break; |
| default: |
| abort(); |
| } |
| z &= ~ roundBitsMask; |
| if (z != float32_val(a)) { |
| status->float_exception_flags |= float_flag_inexact; |
| } |
| return make_float32(z); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of adding the absolute values of the single-precision |
| | floating-point values `a' and `b'. If `zSign' is 1, the sum is negated |
| | before being returned. `zSign' is ignored if the result is a NaN. |
| | The addition is performed according to the IEC/IEEE Standard for Binary |
| | Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| static float32 addFloat32Sigs(float32 a, float32 b, flag zSign, |
| float_status *status) |
| { |
| int aExp, bExp, zExp; |
| uint32_t aSig, bSig, zSig; |
| int expDiff; |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| bSig = extractFloat32Frac( b ); |
| bExp = extractFloat32Exp( b ); |
| expDiff = aExp - bExp; |
| aSig <<= 6; |
| bSig <<= 6; |
| if ( 0 < expDiff ) { |
| if ( aExp == 0xFF ) { |
| if (aSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| return a; |
| } |
| if ( bExp == 0 ) { |
| --expDiff; |
| } |
| else { |
| bSig |= 0x20000000; |
| } |
| shift32RightJamming( bSig, expDiff, &bSig ); |
| zExp = aExp; |
| } |
| else if ( expDiff < 0 ) { |
| if ( bExp == 0xFF ) { |
| if (bSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| return packFloat32( zSign, 0xFF, 0 ); |
| } |
| if ( aExp == 0 ) { |
| ++expDiff; |
| } |
| else { |
| aSig |= 0x20000000; |
| } |
| shift32RightJamming( aSig, - expDiff, &aSig ); |
| zExp = bExp; |
| } |
| else { |
| if ( aExp == 0xFF ) { |
| if (aSig | bSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| return a; |
| } |
| if ( aExp == 0 ) { |
| if (status->flush_to_zero) { |
| if (aSig | bSig) { |
| float_raise(float_flag_output_denormal, status); |
| } |
| return packFloat32(zSign, 0, 0); |
| } |
| return packFloat32( zSign, 0, ( aSig + bSig )>>6 ); |
| } |
| zSig = 0x40000000 + aSig + bSig; |
| zExp = aExp; |
| goto roundAndPack; |
| } |
| aSig |= 0x20000000; |
| zSig = ( aSig + bSig )<<1; |
| --zExp; |
| if ( (int32_t) zSig < 0 ) { |
| zSig = aSig + bSig; |
| ++zExp; |
| } |
| roundAndPack: |
| return roundAndPackFloat32(zSign, zExp, zSig, status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of subtracting the absolute values of the single- |
| | precision floating-point values `a' and `b'. If `zSign' is 1, the |
| | difference is negated before being returned. `zSign' is ignored if the |
| | result is a NaN. The subtraction is performed according to the IEC/IEEE |
| | Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| static float32 subFloat32Sigs(float32 a, float32 b, flag zSign, |
| float_status *status) |
| { |
| int aExp, bExp, zExp; |
| uint32_t aSig, bSig, zSig; |
| int expDiff; |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| bSig = extractFloat32Frac( b ); |
| bExp = extractFloat32Exp( b ); |
| expDiff = aExp - bExp; |
| aSig <<= 7; |
| bSig <<= 7; |
| if ( 0 < expDiff ) goto aExpBigger; |
| if ( expDiff < 0 ) goto bExpBigger; |
| if ( aExp == 0xFF ) { |
| if (aSig | bSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| if ( aExp == 0 ) { |
| aExp = 1; |
| bExp = 1; |
| } |
| if ( bSig < aSig ) goto aBigger; |
| if ( aSig < bSig ) goto bBigger; |
| return packFloat32(status->float_rounding_mode == float_round_down, 0, 0); |
| bExpBigger: |
| if ( bExp == 0xFF ) { |
| if (bSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| return packFloat32( zSign ^ 1, 0xFF, 0 ); |
| } |
| if ( aExp == 0 ) { |
| ++expDiff; |
| } |
| else { |
| aSig |= 0x40000000; |
| } |
| shift32RightJamming( aSig, - expDiff, &aSig ); |
| bSig |= 0x40000000; |
| bBigger: |
| zSig = bSig - aSig; |
| zExp = bExp; |
| zSign ^= 1; |
| goto normalizeRoundAndPack; |
| aExpBigger: |
| if ( aExp == 0xFF ) { |
| if (aSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| return a; |
| } |
| if ( bExp == 0 ) { |
| --expDiff; |
| } |
| else { |
| bSig |= 0x40000000; |
| } |
| shift32RightJamming( bSig, expDiff, &bSig ); |
| aSig |= 0x40000000; |
| aBigger: |
| zSig = aSig - bSig; |
| zExp = aExp; |
| normalizeRoundAndPack: |
| --zExp; |
| return normalizeRoundAndPackFloat32(zSign, zExp, zSig, status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of adding the single-precision floating-point values `a' |
| | and `b'. The operation is performed according to the IEC/IEEE Standard for |
| | Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float32 float32_add(float32 a, float32 b, float_status *status) |
| { |
| flag aSign, bSign; |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| |
| aSign = extractFloat32Sign( a ); |
| bSign = extractFloat32Sign( b ); |
| if ( aSign == bSign ) { |
| return addFloat32Sigs(a, b, aSign, status); |
| } |
| else { |
| return subFloat32Sigs(a, b, aSign, status); |
| } |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of subtracting the single-precision floating-point values |
| | `a' and `b'. The operation is performed according to the IEC/IEEE Standard |
| | for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float32 float32_sub(float32 a, float32 b, float_status *status) |
| { |
| flag aSign, bSign; |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| |
| aSign = extractFloat32Sign( a ); |
| bSign = extractFloat32Sign( b ); |
| if ( aSign == bSign ) { |
| return subFloat32Sigs(a, b, aSign, status); |
| } |
| else { |
| return addFloat32Sigs(a, b, aSign, status); |
| } |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of multiplying the single-precision floating-point values |
| | `a' and `b'. The operation is performed according to the IEC/IEEE Standard |
| | for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float32 float32_mul(float32 a, float32 b, float_status *status) |
| { |
| flag aSign, bSign, zSign; |
| int aExp, bExp, zExp; |
| uint32_t aSig, bSig; |
| uint64_t zSig64; |
| uint32_t zSig; |
| |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| bSig = extractFloat32Frac( b ); |
| bExp = extractFloat32Exp( b ); |
| bSign = extractFloat32Sign( b ); |
| zSign = aSign ^ bSign; |
| if ( aExp == 0xFF ) { |
| if ( aSig || ( ( bExp == 0xFF ) && bSig ) ) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| if ( ( bExp | bSig ) == 0 ) { |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| return packFloat32( zSign, 0xFF, 0 ); |
| } |
| if ( bExp == 0xFF ) { |
| if (bSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| if ( ( aExp | aSig ) == 0 ) { |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| return packFloat32( zSign, 0xFF, 0 ); |
| } |
| if ( aExp == 0 ) { |
| if ( aSig == 0 ) return packFloat32( zSign, 0, 0 ); |
| normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| } |
| if ( bExp == 0 ) { |
| if ( bSig == 0 ) return packFloat32( zSign, 0, 0 ); |
| normalizeFloat32Subnormal( bSig, &bExp, &bSig ); |
| } |
| zExp = aExp + bExp - 0x7F; |
| aSig = ( aSig | 0x00800000 )<<7; |
| bSig = ( bSig | 0x00800000 )<<8; |
| shift64RightJamming( ( (uint64_t) aSig ) * bSig, 32, &zSig64 ); |
| zSig = zSig64; |
| if ( 0 <= (int32_t) ( zSig<<1 ) ) { |
| zSig <<= 1; |
| --zExp; |
| } |
| return roundAndPackFloat32(zSign, zExp, zSig, status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of dividing the single-precision floating-point value `a' |
| | by the corresponding value `b'. The operation is performed according to the |
| | IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float32 float32_div(float32 a, float32 b, float_status *status) |
| { |
| flag aSign, bSign, zSign; |
| int aExp, bExp, zExp; |
| uint32_t aSig, bSig, zSig; |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| bSig = extractFloat32Frac( b ); |
| bExp = extractFloat32Exp( b ); |
| bSign = extractFloat32Sign( b ); |
| zSign = aSign ^ bSign; |
| if ( aExp == 0xFF ) { |
| if (aSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| if ( bExp == 0xFF ) { |
| if (bSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| return packFloat32( zSign, 0xFF, 0 ); |
| } |
| if ( bExp == 0xFF ) { |
| if (bSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| return packFloat32( zSign, 0, 0 ); |
| } |
| if ( bExp == 0 ) { |
| if ( bSig == 0 ) { |
| if ( ( aExp | aSig ) == 0 ) { |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| float_raise(float_flag_divbyzero, status); |
| return packFloat32( zSign, 0xFF, 0 ); |
| } |
| normalizeFloat32Subnormal( bSig, &bExp, &bSig ); |
| } |
| if ( aExp == 0 ) { |
| if ( aSig == 0 ) return packFloat32( zSign, 0, 0 ); |
| normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| } |
| zExp = aExp - bExp + 0x7D; |
| aSig = ( aSig | 0x00800000 )<<7; |
| bSig = ( bSig | 0x00800000 )<<8; |
| if ( bSig <= ( aSig + aSig ) ) { |
| aSig >>= 1; |
| ++zExp; |
| } |
| zSig = ( ( (uint64_t) aSig )<<32 ) / bSig; |
| if ( ( zSig & 0x3F ) == 0 ) { |
| zSig |= ( (uint64_t) bSig * zSig != ( (uint64_t) aSig )<<32 ); |
| } |
| return roundAndPackFloat32(zSign, zExp, zSig, status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the remainder of the single-precision floating-point value `a' |
| | with respect to the corresponding value `b'. The operation is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| float32 float32_rem(float32 a, float32 b, float_status *status) |
| { |
| flag aSign, zSign; |
| int aExp, bExp, expDiff; |
| uint32_t aSig, bSig; |
| uint32_t q; |
| uint64_t aSig64, bSig64, q64; |
| uint32_t alternateASig; |
| int32_t sigMean; |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| bSig = extractFloat32Frac( b ); |
| bExp = extractFloat32Exp( b ); |
| if ( aExp == 0xFF ) { |
| if ( aSig || ( ( bExp == 0xFF ) && bSig ) ) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| if ( bExp == 0xFF ) { |
| if (bSig) { |
| return propagateFloat32NaN(a, b, status); |
| } |
| return a; |
| } |
| if ( bExp == 0 ) { |
| if ( bSig == 0 ) { |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| normalizeFloat32Subnormal( bSig, &bExp, &bSig ); |
| } |
| if ( aExp == 0 ) { |
| if ( aSig == 0 ) return a; |
| normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| } |
| expDiff = aExp - bExp; |
| aSig |= 0x00800000; |
| bSig |= 0x00800000; |
| if ( expDiff < 32 ) { |
| aSig <<= 8; |
| bSig <<= 8; |
| if ( expDiff < 0 ) { |
| if ( expDiff < -1 ) return a; |
| aSig >>= 1; |
| } |
| q = ( bSig <= aSig ); |
| if ( q ) aSig -= bSig; |
| if ( 0 < expDiff ) { |
| q = ( ( (uint64_t) aSig )<<32 ) / bSig; |
| q >>= 32 - expDiff; |
| bSig >>= 2; |
| aSig = ( ( aSig>>1 )<<( expDiff - 1 ) ) - bSig * q; |
| } |
| else { |
| aSig >>= 2; |
| bSig >>= 2; |
| } |
| } |
| else { |
| if ( bSig <= aSig ) aSig -= bSig; |
| aSig64 = ( (uint64_t) aSig )<<40; |
| bSig64 = ( (uint64_t) bSig )<<40; |
| expDiff -= 64; |
| while ( 0 < expDiff ) { |
| q64 = estimateDiv128To64( aSig64, 0, bSig64 ); |
| q64 = ( 2 < q64 ) ? q64 - 2 : 0; |
| aSig64 = - ( ( bSig * q64 )<<38 ); |
| expDiff -= 62; |
| } |
| expDiff += 64; |
| q64 = estimateDiv128To64( aSig64, 0, bSig64 ); |
| q64 = ( 2 < q64 ) ? q64 - 2 : 0; |
| q = q64>>( 64 - expDiff ); |
| bSig <<= 6; |
| aSig = ( ( aSig64>>33 )<<( expDiff - 1 ) ) - bSig * q; |
| } |
| do { |
| alternateASig = aSig; |
| ++q; |
| aSig -= bSig; |
| } while ( 0 <= (int32_t) aSig ); |
| sigMean = aSig + alternateASig; |
| if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) { |
| aSig = alternateASig; |
| } |
| zSign = ( (int32_t) aSig < 0 ); |
| if ( zSign ) aSig = - aSig; |
| return normalizeRoundAndPackFloat32(aSign ^ zSign, bExp, aSig, status); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the result of multiplying the single-precision floating-point values |
| | `a' and `b' then adding 'c', with no intermediate rounding step after the |
| | multiplication. The operation is performed according to the IEC/IEEE |
| | Standard for Binary Floating-Point Arithmetic 754-2008. |
| | The flags argument allows the caller to select negation of the |
| | addend, the intermediate product, or the final result. (The difference |
| | between this and having the caller do a separate negation is that negating |
| | externally will flip the sign bit on NaNs.) |
| *----------------------------------------------------------------------------*/ |
| |
| float32 float32_muladd(float32 a, float32 b, float32 c, int flags, |
| float_status *status) |
| { |
| flag aSign, bSign, cSign, zSign; |
| int aExp, bExp, cExp, pExp, zExp, expDiff; |
| uint32_t aSig, bSig, cSig; |
| flag pInf, pZero, pSign; |
| uint64_t pSig64, cSig64, zSig64; |
| uint32_t pSig; |
| int shiftcount; |
| flag signflip, infzero; |
| |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| c = float32_squash_input_denormal(c, status); |
| aSig = extractFloat32Frac(a); |
| aExp = extractFloat32Exp(a); |
| aSign = extractFloat32Sign(a); |
| bSig = extractFloat32Frac(b); |
| bExp = extractFloat32Exp(b); |
| bSign = extractFloat32Sign(b); |
| cSig = extractFloat32Frac(c); |
| cExp = extractFloat32Exp(c); |
| cSign = extractFloat32Sign(c); |
| |
| infzero = ((aExp == 0 && aSig == 0 && bExp == 0xff && bSig == 0) || |
| (aExp == 0xff && aSig == 0 && bExp == 0 && bSig == 0)); |
| |
| /* It is implementation-defined whether the cases of (0,inf,qnan) |
| * and (inf,0,qnan) raise InvalidOperation or not (and what QNaN |
| * they return if they do), so we have to hand this information |
| * off to the target-specific pick-a-NaN routine. |
| */ |
| if (((aExp == 0xff) && aSig) || |
| ((bExp == 0xff) && bSig) || |
| ((cExp == 0xff) && cSig)) { |
| return propagateFloat32MulAddNaN(a, b, c, infzero, status); |
| } |
| |
| if (infzero) { |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| |
| if (flags & float_muladd_negate_c) { |
| cSign ^= 1; |
| } |
| |
| signflip = (flags & float_muladd_negate_result) ? 1 : 0; |
| |
| /* Work out the sign and type of the product */ |
| pSign = aSign ^ bSign; |
| if (flags & float_muladd_negate_product) { |
| pSign ^= 1; |
| } |
| pInf = (aExp == 0xff) || (bExp == 0xff); |
| pZero = ((aExp | aSig) == 0) || ((bExp | bSig) == 0); |
| |
| if (cExp == 0xff) { |
| if (pInf && (pSign ^ cSign)) { |
| /* addition of opposite-signed infinities => InvalidOperation */ |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| /* Otherwise generate an infinity of the same sign */ |
| return packFloat32(cSign ^ signflip, 0xff, 0); |
| } |
| |
| if (pInf) { |
| return packFloat32(pSign ^ signflip, 0xff, 0); |
| } |
| |
| if (pZero) { |
| if (cExp == 0) { |
| if (cSig == 0) { |
| /* Adding two exact zeroes */ |
| if (pSign == cSign) { |
| zSign = pSign; |
| } else if (status->float_rounding_mode == float_round_down) { |
| zSign = 1; |
| } else { |
| zSign = 0; |
| } |
| return packFloat32(zSign ^ signflip, 0, 0); |
| } |
| /* Exact zero plus a denorm */ |
| if (status->flush_to_zero) { |
| float_raise(float_flag_output_denormal, status); |
| return packFloat32(cSign ^ signflip, 0, 0); |
| } |
| } |
| /* Zero plus something non-zero : just return the something */ |
| if (flags & float_muladd_halve_result) { |
| if (cExp == 0) { |
| normalizeFloat32Subnormal(cSig, &cExp, &cSig); |
| } |
| /* Subtract one to halve, and one again because roundAndPackFloat32 |
| * wants one less than the true exponent. |
| */ |
| cExp -= 2; |
| cSig = (cSig | 0x00800000) << 7; |
| return roundAndPackFloat32(cSign ^ signflip, cExp, cSig, status); |
| } |
| return packFloat32(cSign ^ signflip, cExp, cSig); |
| } |
| |
| if (aExp == 0) { |
| normalizeFloat32Subnormal(aSig, &aExp, &aSig); |
| } |
| if (bExp == 0) { |
| normalizeFloat32Subnormal(bSig, &bExp, &bSig); |
| } |
| |
| /* Calculate the actual result a * b + c */ |
| |
| /* Multiply first; this is easy. */ |
| /* NB: we subtract 0x7e where float32_mul() subtracts 0x7f |
| * because we want the true exponent, not the "one-less-than" |
| * flavour that roundAndPackFloat32() takes. |
| */ |
| pExp = aExp + bExp - 0x7e; |
| aSig = (aSig | 0x00800000) << 7; |
| bSig = (bSig | 0x00800000) << 8; |
| pSig64 = (uint64_t)aSig * bSig; |
| if ((int64_t)(pSig64 << 1) >= 0) { |
| pSig64 <<= 1; |
| pExp--; |
| } |
| |
| zSign = pSign ^ signflip; |
| |
| /* Now pSig64 is the significand of the multiply, with the explicit bit in |
| * position 62. |
| */ |
| if (cExp == 0) { |
| if (!cSig) { |
| /* Throw out the special case of c being an exact zero now */ |
| shift64RightJamming(pSig64, 32, &pSig64); |
| pSig = pSig64; |
| if (flags & float_muladd_halve_result) { |
| pExp--; |
| } |
| return roundAndPackFloat32(zSign, pExp - 1, |
| pSig, status); |
| } |
| normalizeFloat32Subnormal(cSig, &cExp, &cSig); |
| } |
| |
| cSig64 = (uint64_t)cSig << (62 - 23); |
| cSig64 |= LIT64(0x4000000000000000); |
| expDiff = pExp - cExp; |
| |
| if (pSign == cSign) { |
| /* Addition */ |
| if (expDiff > 0) { |
| /* scale c to match p */ |
| shift64RightJamming(cSig64, expDiff, &cSig64); |
| zExp = pExp; |
| } else if (expDiff < 0) { |
| /* scale p to match c */ |
| shift64RightJamming(pSig64, -expDiff, &pSig64); |
| zExp = cExp; |
| } else { |
| /* no scaling needed */ |
| zExp = cExp; |
| } |
| /* Add significands and make sure explicit bit ends up in posn 62 */ |
| zSig64 = pSig64 + cSig64; |
| if ((int64_t)zSig64 < 0) { |
| shift64RightJamming(zSig64, 1, &zSig64); |
| } else { |
| zExp--; |
| } |
| } else { |
| /* Subtraction */ |
| if (expDiff > 0) { |
| shift64RightJamming(cSig64, expDiff, &cSig64); |
| zSig64 = pSig64 - cSig64; |
| zExp = pExp; |
| } else if (expDiff < 0) { |
| shift64RightJamming(pSig64, -expDiff, &pSig64); |
| zSig64 = cSig64 - pSig64; |
| zExp = cExp; |
| zSign ^= 1; |
| } else { |
| zExp = pExp; |
| if (cSig64 < pSig64) { |
| zSig64 = pSig64 - cSig64; |
| } else if (pSig64 < cSig64) { |
| zSig64 = cSig64 - pSig64; |
| zSign ^= 1; |
| } else { |
| /* Exact zero */ |
| zSign = signflip; |
| if (status->float_rounding_mode == float_round_down) { |
| zSign ^= 1; |
| } |
| return packFloat32(zSign, 0, 0); |
| } |
| } |
| --zExp; |
| /* Normalize to put the explicit bit back into bit 62. */ |
| shiftcount = countLeadingZeros64(zSig64) - 1; |
| zSig64 <<= shiftcount; |
| zExp -= shiftcount; |
| } |
| if (flags & float_muladd_halve_result) { |
| zExp--; |
| } |
| |
| shift64RightJamming(zSig64, 32, &zSig64); |
| return roundAndPackFloat32(zSign, zExp, zSig64, status); |
| } |
| |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the square root 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_sqrt(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp, zExp; |
| uint32_t aSig, zSig; |
| uint64_t rem, term; |
| a = float32_squash_input_denormal(a, status); |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| if ( aExp == 0xFF ) { |
| if (aSig) { |
| return propagateFloat32NaN(a, float32_zero, status); |
| } |
| if ( ! aSign ) return a; |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| if ( aSign ) { |
| if ( ( aExp | aSig ) == 0 ) return a; |
| float_raise(float_flag_invalid, status); |
| return float32_default_nan(status); |
| } |
| if ( aExp == 0 ) { |
| if ( aSig == 0 ) return float32_zero; |
| normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| } |
| zExp = ( ( aExp - 0x7F )>>1 ) + 0x7E; |
| aSig = ( aSig | 0x00800000 )<<8; |
| zSig = estimateSqrt32( aExp, aSig ) + 2; |
| if ( ( zSig & 0x7F ) <= 5 ) { |
| if ( zSig < 2 ) { |
| zSig = 0x7FFFFFFF; |
| goto roundAndPack; |
| } |
| aSig >>= aExp & 1; |
| term = ( (uint64_t) zSig ) * zSig; |
| rem = ( ( (uint64_t) aSig )<<32 ) - term; |
| while ( (int64_t) rem < 0 ) { |
| --zSig; |
| rem += ( ( (uint64_t) zSig )<<1 ) | 1; |
| } |
| zSig |= ( rem != 0 ); |
| } |
| shift32RightJamming( zSig, 1, &zSig ); |
| roundAndPack: |
| return roundAndPackFloat32(0, zExp, zSig, status); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns the binary exponential of the single-precision floating-point value |
| | `a'. The operation is performed according to the IEC/IEEE Standard for |
| | Binary Floating-Point Arithmetic. |
| | |
| | Uses the following identities: |
| | |
| | 1. ------------------------------------------------------------------------- |
| | x x*ln(2) |
| | 2 = e |
| | |
| | 2. ------------------------------------------------------------------------- |
| | 2 3 4 5 n |
| | x x x x x x x |
| | e = 1 + --- + --- + --- + --- + --- + ... + --- + ... |
| | 1! 2! 3! 4! 5! n! |
| *----------------------------------------------------------------------------*/ |
| |
| static const float64 float32_exp2_coefficients[15] = |
| { |
| const_float64( 0x3ff0000000000000ll ), /* 1 */ |
| const_float64( 0x3fe0000000000000ll ), /* 2 */ |
| const_float64( 0x3fc5555555555555ll ), /* 3 */ |
| const_float64( 0x3fa5555555555555ll ), /* 4 */ |
| const_float64( 0x3f81111111111111ll ), /* 5 */ |
| const_float64( 0x3f56c16c16c16c17ll ), /* 6 */ |
| const_float64( 0x3f2a01a01a01a01all ), /* 7 */ |
| const_float64( 0x3efa01a01a01a01all ), /* 8 */ |
| const_float64( 0x3ec71de3a556c734ll ), /* 9 */ |
| const_float64( 0x3e927e4fb7789f5cll ), /* 10 */ |
| const_float64( 0x3e5ae64567f544e4ll ), /* 11 */ |
| const_float64( 0x3e21eed8eff8d898ll ), /* 12 */ |
| const_float64( 0x3de6124613a86d09ll ), /* 13 */ |
| const_float64( 0x3da93974a8c07c9dll ), /* 14 */ |
| const_float64( 0x3d6ae7f3e733b81fll ), /* 15 */ |
| }; |
| |
| float32 float32_exp2(float32 a, float_status *status) |
| { |
| flag aSign; |
| int aExp; |
| uint32_t aSig; |
| float64 r, x, xn; |
| int i; |
| a = float32_squash_input_denormal(a, status); |
| |
| aSig = extractFloat32Frac( a ); |
| aExp = extractFloat32Exp( a ); |
| aSign = extractFloat32Sign( a ); |
| |
| if ( aExp == 0xFF) { |
| if (aSig) { |
| return propagateFloat32NaN(a, float32_zero, status); |
| } |
| return (aSign) ? float32_zero : a; |
| } |
| if (aExp == 0) { |
| if (aSig == 0) return float32_one; |
| } |
| |
| float_raise(float_flag_inexact, status); |
| |
| /* ******************************* */ |
| /* using float64 for approximation */ |
| /* ******************************* */ |
| x = float32_to_float64(a, status); |
| x = float64_mul(x, float64_ln2, status); |
| |
| xn = x; |
| r = float64_one; |
| for (i = 0 ; i < 15 ; i++) { |
| float64 f; |
| |
| f = float64_mul(xn, float32_exp2_coefficients[i], status); |
| r = float64_add(r, f, status); |
| |
| xn = float64_mul(xn, x, status); |
| } |
| |
| return float64_to_float32(r, status); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | 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, float_status *status) |
| { |
| flag aSign, zSign; |
| int aExp; |
| uint32_t aSig, zSig, i; |
| |
| a = float32_squash_input_denormal(a, status); |
| 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); |
| return float32_default_nan(status); |
| } |
| if ( aExp == 0xFF ) { |
| if (aSig) { |
| return propagateFloat32NaN(a, float32_zero, status); |
| } |
| return a; |
| } |
| |
| aExp -= 0x7F; |
| aSig |= 0x00800000; |
| zSign = aExp < 0; |
| zSig = aExp << 23; |
| |
| for (i = 1 << 22; i > 0; i >>= 1) { |
| aSig = ( (uint64_t)aSig * aSig ) >> 23; |
| if ( aSig & 0x01000000 ) { |
| aSig >>= 1; |
| zSig |= i; |
| } |
| } |
| |
| if ( zSign ) |
| zSig = -zSig; |
| |
| return normalizeRoundAndPackFloat32(zSign, 0x85, zSig, status); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns 1 if the single-precision floating-point value `a' is equal to |
| | the corresponding value `b', and 0 otherwise. The invalid exception is |
| | raised if either operand is a NaN. Otherwise, the comparison is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| int float32_eq(float32 a, float32 b, float_status *status) |
| { |
| uint32_t av, bv; |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| |
| if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| ) { |
| float_raise(float_flag_invalid, status); |
| return 0; |
| } |
| av = float32_val(a); |
| bv = float32_val(b); |
| return ( av == bv ) || ( (uint32_t) ( ( av | bv )<<1 ) == 0 ); |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns 1 if the single-precision floating-point value `a' is less than |
| | or equal to the corresponding value `b', and 0 otherwise. The invalid |
| | exception is raised if either operand is a NaN. The comparison is performed |
| | according to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| int float32_le(float32 a, float32 b, float_status *status) |
| { |
| flag aSign, bSign; |
| uint32_t av, bv; |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| |
| if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| ) { |
| float_raise(float_flag_invalid, status); |
| return 0; |
| } |
| aSign = extractFloat32Sign( a ); |
| bSign = extractFloat32Sign( b ); |
| av = float32_val(a); |
| bv = float32_val(b); |
| if ( aSign != bSign ) return aSign || ( (uint32_t) ( ( av | bv )<<1 ) == 0 ); |
| return ( av == bv ) || ( aSign ^ ( av < bv ) ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns 1 if the single-precision floating-point value `a' is less than |
| | the corresponding value `b', and 0 otherwise. The invalid exception is |
| | raised if either operand is a NaN. The comparison is performed according |
| | to the IEC/IEEE Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| int float32_lt(float32 a, float32 b, float_status *status) |
| { |
| flag aSign, bSign; |
| uint32_t av, bv; |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| |
| if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| ) { |
| float_raise(float_flag_invalid, status); |
| return 0; |
| } |
| aSign = extractFloat32Sign( a ); |
| bSign = extractFloat32Sign( b ); |
| av = float32_val(a); |
| bv = float32_val(b); |
| if ( aSign != bSign ) return aSign && ( (uint32_t) ( ( av | bv )<<1 ) != 0 ); |
| return ( av != bv ) && ( aSign ^ ( av < bv ) ); |
| |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns 1 if the single-precision floating-point values `a' and `b' cannot |
| | be compared, and 0 otherwise. The invalid exception is raised if either |
| | operand is a NaN. The comparison is performed according to the IEC/IEEE |
| | Standard for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| int float32_unordered(float32 a, float32 b, float_status *status) |
| { |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| |
| if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| ) { |
| float_raise(float_flag_invalid, status); |
| return 1; |
| } |
| return 0; |
| } |
| |
| /*---------------------------------------------------------------------------- |
| | Returns 1 if the single-precision floating-point value `a' is equal to |
| | the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an |
| | exception. The comparison is performed according to the IEC/IEEE Standard |
| | for Binary Floating-Point Arithmetic. |
| *----------------------------------------------------------------------------*/ |
| |
| int float32_eq_quiet(float32 a, float32 b, float_status *status) |
| { |
| a = float32_squash_input_denormal(a, status); |
| b = float32_squash_input_denormal(b, status); |
| |
| if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| ) { |
| if (float32_is_signaling_nan(a, status) |
| || float32_is_signaling_nan(b, status)) { |
| float_raise(float_flag_invalid, status); |
| } |
| return 0; |
| } |
| return ( float32_val(a) == float32_val(b) ) || |
| ( (uint32_t) ( ( float32_val( |