diff options
Diffstat (limited to 'lib/libutils/isoc/arch/arm/softfloat/source/f64_div.c')
| -rw-r--r-- | lib/libutils/isoc/arch/arm/softfloat/source/f64_div.c | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/lib/libutils/isoc/arch/arm/softfloat/source/f64_div.c b/lib/libutils/isoc/arch/arm/softfloat/source/f64_div.c new file mode 100644 index 0000000..96523f0 --- /dev/null +++ b/lib/libutils/isoc/arch/arm/softfloat/source/f64_div.c @@ -0,0 +1,172 @@ + +/*============================================================================ + +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_div( float64_t a, float64_t b ) +{ + union ui64_f64 uA; + uint_fast64_t uiA; + bool signA; + int_fast16_t expA; + uint_fast64_t sigA; + union ui64_f64 uB; + uint_fast64_t uiB; + bool signB; + int_fast16_t expB; + uint_fast64_t sigB; + bool signZ; + struct exp16_sig64 normExpSig; + int_fast16_t expZ; + uint32_t recip32, sig32Z, doubleTerm; + uint_fast64_t rem; + uint32_t q; + uint_fast64_t sigZ; + uint_fast64_t uiZ; + union ui64_f64 uZ; + + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + uA.f = a; + uiA = uA.ui; + signA = signF64UI( uiA ); + expA = expF64UI( uiA ); + sigA = fracF64UI( uiA ); + uB.f = b; + uiB = uB.ui; + signB = signF64UI( uiB ); + expB = expF64UI( uiB ); + sigB = fracF64UI( uiB ); + signZ = signA ^ signB; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( expA == 0x7FF ) { + if ( sigA ) goto propagateNaN; + if ( expB == 0x7FF ) { + if ( sigB ) goto propagateNaN; + goto invalid; + } + goto infinity; + } + if ( expB == 0x7FF ) { + if ( sigB ) goto propagateNaN; + goto zero; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( ! expB ) { + if ( ! sigB ) { + if ( ! (expA | sigA) ) goto invalid; + softfloat_raiseFlags( softfloat_flag_infinite ); + goto infinity; + } + normExpSig = softfloat_normSubnormalF64Sig( sigB ); + expB = normExpSig.exp; + sigB = normExpSig.sig; + } + if ( ! expA ) { + if ( ! sigA ) goto zero; + normExpSig = softfloat_normSubnormalF64Sig( sigA ); + expA = normExpSig.exp; + sigA = normExpSig.sig; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + expZ = expA - expB + 0x3FE; + sigA |= UINT64_C( 0x0010000000000000 ); + sigB |= UINT64_C( 0x0010000000000000 ); + if ( sigA < sigB ) { + --expZ; + sigA <<= 11; + } else { + sigA <<= 10; + } + sigB <<= 11; + recip32 = softfloat_approxRecip32_1( sigB>>32 ) - 2; + sig32Z = ((uint32_t) (sigA>>32) * (uint_fast64_t) recip32)>>32; + doubleTerm = sig32Z<<1; + rem = + ((sigA - (uint_fast64_t) doubleTerm * (uint32_t) (sigB>>32))<<28) + - (uint_fast64_t) doubleTerm * ((uint32_t) sigB>>4); + q = (((uint32_t) (rem>>32) * (uint_fast64_t) recip32)>>32) + 4; + sigZ = ((uint_fast64_t) sig32Z<<32) + ((uint_fast64_t) q<<4); + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( (sigZ & 0x1FF) < 4<<4 ) { + q &= ~7; + sigZ &= ~(uint_fast64_t) 0x7F; + doubleTerm = q<<1; + rem = + ((rem - (uint_fast64_t) doubleTerm * (uint32_t) (sigB>>32))<<28) + - (uint_fast64_t) doubleTerm * ((uint32_t) sigB>>4); + if ( rem & UINT64_C( 0x8000000000000000 ) ) { + sigZ -= 1<<7; + } else { + if ( rem ) sigZ |= 1; + } + } + return softfloat_roundPackToF64( signZ, expZ, sigZ ); + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + propagateNaN: + uiZ = softfloat_propagateNaNF64UI( uiA, uiB ); + goto uiZ; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + invalid: + softfloat_raiseFlags( softfloat_flag_invalid ); + uiZ = defaultNaNF64UI; + goto uiZ; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + infinity: + uiZ = packToF64UI( signZ, 0x7FF, 0 ); + goto uiZ; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + zero: + uiZ = packToF64UI( signZ, 0, 0 ); + uiZ: + uZ.ui = uiZ; + return uZ.f; + +} + |