diff options
Diffstat (limited to 'src/libs/softfloat-3e/source/s_roundPackToF64.c')
-rw-r--r-- | src/libs/softfloat-3e/source/s_roundPackToF64.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/src/libs/softfloat-3e/source/s_roundPackToF64.c b/src/libs/softfloat-3e/source/s_roundPackToF64.c new file mode 100644 index 00000000..f44c9840 --- /dev/null +++ b/src/libs/softfloat-3e/source/s_roundPackToF64.c @@ -0,0 +1,118 @@ + +/*============================================================================ + +This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic +Package, Release 3e, by John R. Hauser. + +Copyright 2011, 2012, 2013, 2014, 2015, 2017 The Regents of the University of +California. 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 University 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 REGENTS 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 REGENTS 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. + +=============================================================================*/ + +#include <stdbool.h> +#include <stdint.h> +#include "platform.h" +#include "internals.h" +#include "softfloat.h" + +float64_t + softfloat_roundPackToF64( bool sign, int_fast16_t exp, uint_fast64_t sig SOFTFLOAT_STATE_DECL_COMMA ) +{ + uint_fast8_t roundingMode; + bool roundNearEven; + uint_fast16_t roundIncrement, roundBits; + bool isTiny; + uint_fast64_t uiZ; + union ui64_f64 uZ; + + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + roundingMode = softfloat_roundingMode; + roundNearEven = (roundingMode == softfloat_round_near_even); + roundIncrement = 0x200; + if ( ! roundNearEven && (roundingMode != softfloat_round_near_maxMag) ) { + roundIncrement = + (roundingMode + == (sign ? softfloat_round_min : softfloat_round_max)) + ? 0x3FF + : 0; + } + roundBits = sig & 0x3FF; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( 0x7FD <= (uint16_t) exp ) { + if ( exp < 0 ) { + /*---------------------------------------------------------------- + *----------------------------------------------------------------*/ + isTiny = + (softfloat_detectTininess == softfloat_tininess_beforeRounding) + || (exp < -1) + || (sig + roundIncrement < UINT64_C( 0x8000000000000000 )); + sig = softfloat_shiftRightJam64( sig, -exp ); + exp = 0; + roundBits = sig & 0x3FF; + if ( isTiny && roundBits ) { + softfloat_raiseFlags( softfloat_flag_underflow SOFTFLOAT_STATE_ARG_COMMA ); + } + } else if ( + (0x7FD < exp) + || (UINT64_C( 0x8000000000000000 ) <= sig + roundIncrement) + ) { + /*---------------------------------------------------------------- + *----------------------------------------------------------------*/ + softfloat_raiseFlags( + softfloat_flag_overflow | softfloat_flag_inexact + SOFTFLOAT_STATE_ARG_COMMA ); + uiZ = packToF64UI( sign, 0x7FF, 0 ) - ! roundIncrement; + goto uiZ; + } + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + sig = (sig + roundIncrement)>>10; + if ( roundBits ) { + softfloat_exceptionFlags |= softfloat_flag_inexact; +#ifdef SOFTFLOAT_ROUND_ODD + if ( roundingMode == softfloat_round_odd ) { + sig |= 1; + goto packReturn; + } +#endif + } + sig &= ~(uint_fast64_t) (! (roundBits ^ 0x200) & roundNearEven); + if ( ! sig ) exp = 0; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + packReturn: + uiZ = packToF64UI( sign, exp, sig ); + uiZ: + uZ.ui = uiZ; + return uZ.f; + +} + |