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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/f64_to_f32.c | |
parent | 8e69141749065ff957383d2112768f95a33429b6 (diff) | |
download | pk-5cd8d2b93fad2011fdf8f49a263d77697af35b32.zip pk-5cd8d2b93fad2011fdf8f49a263d77697af35b32.tar.gz pk-5cd8d2b93fad2011fdf8f49a263d77697af35b32.tar.bz2 |
Upgrade to SoftFloat 3e
Diffstat (limited to 'softfloat/f64_to_f32.c')
-rw-r--r--[-rwxr-xr-x] | softfloat/f64_to_f32.c | 133 |
1 files changed, 88 insertions, 45 deletions
diff --git a/softfloat/f64_to_f32.c b/softfloat/f64_to_f32.c index 6882e9d..6074bb8 100755..100644 --- a/softfloat/f64_to_f32.c +++ b/softfloat/f64_to_f32.c @@ -1,45 +1,88 @@ -// See LICENSE.SoftFloat for license details. - -
-#include <stdbool.h>
-#include <stdint.h>
-#include "platform.h"
-#include "primitives.h"
-#include "internals.h"
-#include "specialize.h"
-#include "softfloat.h"
-
-float32_t f64_to_f32( float64_t a )
-{
- union ui64_f64 uA;
- uint_fast64_t uiA;
- bool sign;
- int_fast16_t exp;
- uint_fast64_t sig;
- uint_fast32_t uiZ, sig32;
- union ui32_f32 uZ;
-
- uA.f = a;
- uiA = uA.ui;
- sign = signF64UI( uiA );
- exp = expF64UI( uiA );
- sig = fracF64UI( uiA );
- if ( exp == 0x7FF ) {
- uiZ =
- sig ? softfloat_commonNaNToF32UI(
- softfloat_f64UIToCommonNaN( uiA ) )
- : packToF32UI( sign, 0xFF, 0 );
- goto uiZ;
- }
- sig32 = softfloat_shortShift64RightJam( sig, 22 );
- if ( ! ( exp | sig32 ) ) {
- uiZ = packToF32UI( sign, 0, 0 );
- goto uiZ;
- }
- return softfloat_roundPackToF32( sign, exp - 0x381, sig32 | 0x40000000 );
- uiZ:
- uZ.ui = uiZ;
- return uZ.f;
-
-}
-
+ +/*============================================================================ + +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" + +float32_t f64_to_f32( float64_t a ) +{ + union ui64_f64 uA; + uint_fast64_t uiA; + bool sign; + int_fast16_t exp; + uint_fast64_t frac; + struct commonNaN commonNaN; + uint_fast32_t uiZ, frac32; + union ui32_f32 uZ; + + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + uA.f = a; + uiA = uA.ui; + sign = signF64UI( uiA ); + exp = expF64UI( uiA ); + frac = fracF64UI( uiA ); + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + if ( exp == 0x7FF ) { + if ( frac ) { + softfloat_f64UIToCommonNaN( uiA, &commonNaN ); + uiZ = softfloat_commonNaNToF32UI( &commonNaN ); + } else { + uiZ = packToF32UI( sign, 0xFF, 0 ); + } + goto uiZ; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + frac32 = softfloat_shortShiftRightJam64( frac, 22 ); + if ( ! (exp | frac32) ) { + uiZ = packToF32UI( sign, 0, 0 ); + goto uiZ; + } + /*------------------------------------------------------------------------ + *------------------------------------------------------------------------*/ + return softfloat_roundPackToF32( sign, exp - 0x381, frac32 | 0x40000000 ); + uiZ: + uZ.ui = uiZ; + return uZ.f; + +} + |