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author | Andrew Waterman <andrew@sifive.com> | 2018-07-11 01:16:28 -0700 |
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committer | Andrew Waterman <andrew@sifive.com> | 2018-07-11 01:16:28 -0700 |
commit | 5cd8d2b93fad2011fdf8f49a263d77697af35b32 (patch) | |
tree | f6fb9cb6d3bef2aa5c9903511b92e5a6e99e9519 /softfloat/f16_mul.c | |
parent | 8e69141749065ff957383d2112768f95a33429b6 (diff) | |
download | riscv-pk-5cd8d2b93fad2011fdf8f49a263d77697af35b32.zip riscv-pk-5cd8d2b93fad2011fdf8f49a263d77697af35b32.tar.gz riscv-pk-5cd8d2b93fad2011fdf8f49a263d77697af35b32.tar.bz2 |
Upgrade to SoftFloat 3e
Diffstat (limited to 'softfloat/f16_mul.c')
-rw-r--r-- | softfloat/f16_mul.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/softfloat/f16_mul.c b/softfloat/f16_mul.c new file mode 100644 index 0000000..112111d --- /dev/null +++ b/softfloat/f16_mul.c @@ -0,0 +1,140 @@ + +/*============================================================================ + +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 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" + +float16_t f16_mul( float16_t a, float16_t b ) +{ + union ui16_f16 uA; + uint_fast16_t uiA; + bool signA; + int_fast8_t expA; + uint_fast16_t sigA; + union ui16_f16 uB; + uint_fast16_t uiB; + bool signB; + int_fast8_t expB; + uint_fast16_t sigB; + bool signZ; + uint_fast16_t magBits; + struct exp8_sig16 normExpSig; + int_fast8_t expZ; + uint_fast32_t sig32Z; + uint_fast16_t sigZ, uiZ; + union ui16_f16 uZ; + + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + uA.f = a; + uiA = uA.ui; + signA = signF16UI( uiA ); + expA = expF16UI( uiA ); + sigA = fracF16UI( uiA ); + uB.f = b; + uiB = uB.ui; + signB = signF16UI( uiB ); + expB = expF16UI( uiB ); + sigB = fracF16UI( uiB ); + signZ = signA ^ signB; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( expA == 0x1F ) { + if ( sigA || ((expB == 0x1F) && sigB) ) goto propagateNaN; + magBits = expB | sigB; + goto infArg; + } + if ( expB == 0x1F ) { + if ( sigB ) goto propagateNaN; + magBits = expA | sigA; + goto infArg; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( ! expA ) { + if ( ! sigA ) goto zero; + normExpSig = softfloat_normSubnormalF16Sig( sigA ); + expA = normExpSig.exp; + sigA = normExpSig.sig; + } + if ( ! expB ) { + if ( ! sigB ) goto zero; + normExpSig = softfloat_normSubnormalF16Sig( sigB ); + expB = normExpSig.exp; + sigB = normExpSig.sig; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + expZ = expA + expB - 0xF; + sigA = (sigA | 0x0400)<<4; + sigB = (sigB | 0x0400)<<5; + sig32Z = (uint_fast32_t) sigA * sigB; + sigZ = sig32Z>>16; + if ( sig32Z & 0xFFFF ) sigZ |= 1; + if ( sigZ < 0x4000 ) { + --expZ; + sigZ <<= 1; + } + return softfloat_roundPackToF16( signZ, expZ, sigZ ); + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + propagateNaN: + uiZ = softfloat_propagateNaNF16UI( uiA, uiB ); + goto uiZ; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + infArg: + if ( ! magBits ) { + softfloat_raiseFlags( softfloat_flag_invalid ); + uiZ = defaultNaNF16UI; + } else { + uiZ = packToF16UI( signZ, 0x1F, 0 ); + } + goto uiZ; + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + zero: + uiZ = packToF16UI( signZ, 0, 0 ); + uiZ: + uZ.ui = uiZ; + return uZ.f; + +} + |