diff options
Diffstat (limited to 'lib/libutils/isoc/arch/arm/softfloat/source/f64_roundToInt.c')
-rw-r--r-- | lib/libutils/isoc/arch/arm/softfloat/source/f64_roundToInt.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/lib/libutils/isoc/arch/arm/softfloat/source/f64_roundToInt.c b/lib/libutils/isoc/arch/arm/softfloat/source/f64_roundToInt.c new file mode 100644 index 0000000..94fe40d --- /dev/null +++ b/lib/libutils/isoc/arch/arm/softfloat/source/f64_roundToInt.c @@ -0,0 +1,111 @@ + +/*============================================================================ + +This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic +Package, Release 3a, by John R. Hauser. + +Copyright 2011, 2012, 2013, 2014 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 "specialize.h" +#include "softfloat.h" + +float64_t f64_roundToInt( float64_t a, uint_fast8_t roundingMode, bool exact ) +{ + union ui64_f64 uA; + uint_fast64_t uiA; + int_fast16_t exp; + uint_fast64_t uiZ, lastBitMask, roundBitsMask; + union ui64_f64 uZ; + + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + uA.f = a; + uiA = uA.ui; + exp = expF64UI( uiA ); + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( exp <= 0x3FE ) { + if ( ! (uiA & UINT64_C( 0x7FFFFFFFFFFFFFFF )) ) return a; + if ( exact ) softfloat_exceptionFlags |= softfloat_flag_inexact; + uiZ = uiA & packToF64UI( 1, 0, 0 ); + switch ( roundingMode ) { + case softfloat_round_near_even: + if ( ! fracF64UI( uiA ) ) break; + case softfloat_round_near_maxMag: + if ( exp == 0x3FE ) uiZ |= packToF64UI( 0, 0x3FF, 0 ); + break; + case softfloat_round_min: + if ( uiZ ) uiZ = packToF64UI( 1, 0x3FF, 0 ); + break; + case softfloat_round_max: + if ( ! uiZ ) uiZ = packToF64UI( 0, 0x3FF, 0 ); + break; + } + goto uiZ; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( 0x433 <= exp ) { + if ( (exp == 0x7FF) && fracF64UI( uiA ) ) { + uiZ = softfloat_propagateNaNF64UI( uiA, 0 ); + goto uiZ; + } + return a; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + uiZ = uiA; + lastBitMask = (uint_fast64_t) 1<<(0x433 - exp); + roundBitsMask = lastBitMask - 1; + if ( roundingMode == softfloat_round_near_maxMag ) { + uiZ += lastBitMask>>1; + } else if ( roundingMode == softfloat_round_near_even ) { + uiZ += lastBitMask>>1; + if ( ! (uiZ & roundBitsMask) ) uiZ &= ~lastBitMask; + } else if ( roundingMode != softfloat_round_minMag ) { + if ( signF64UI( uiZ ) ^ (roundingMode == softfloat_round_max) ) { + uiZ += roundBitsMask; + } + } + uiZ &= ~roundBitsMask; + if ( exact && (uiZ != uiA) ) { + softfloat_exceptionFlags |= softfloat_flag_inexact; + } + uiZ: + uZ.ui = uiZ; + return uZ.f; + +} + |