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Diffstat (limited to 'source/f32_to_f64.c')
-rw-r--r-- | source/f32_to_f64.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/source/f32_to_f64.c b/source/f32_to_f64.c new file mode 100644 index 0000000..0245394 --- /dev/null +++ b/source/f32_to_f64.c @@ -0,0 +1,82 @@ + +/*============================================================================ + +This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic +Package, Release 3, by John R. Hauser. + +Copyright 2011, 2012, 2013, 2014 The Regents of the University of California +(Regents). All Rights Reserved. Redistribution and use in source and binary +forms, with or without modification, are permitted provided that the following +conditions are met: + +Redistributions of source code must retain the above copyright notice, +this list of conditions, and the following two paragraphs of disclaimer. +Redistributions in binary form must reproduce the above copyright notice, +this list of conditions, and the following two paragraphs of disclaimer in the +documentation and/or other materials provided with the distribution. Neither +the name of the Regents nor the names of its contributors may be used to +endorse or promote products derived from this software without specific prior +written permission. + +IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, +SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING +OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF REGENTS HAS +BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED +TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +PURPOSE. THE SOFTWARE AND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED +HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO OBLIGATION TO PROVIDE +MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. + +=============================================================================*/ + +#include <stdbool.h> +#include <stdint.h> +#include "platform.h" +#include "internals.h" +#include "specialize.h" +#include "softfloat.h" + +float64_t f32_to_f64( float32_t a ) +{ + union ui32_f32 uA; + uint_fast32_t uiA; + bool sign; + int_fast16_t exp; + uint_fast32_t sig; + struct commonNaN commonNaN; + uint_fast64_t uiZ; + struct exp16_sig32 normExpSig; + union ui64_f64 uZ; + + uA.f = a; + uiA = uA.ui; + sign = signF32UI( uiA ); + exp = expF32UI( uiA ); + sig = fracF32UI( uiA ); + if ( exp == 0xFF ) { + if ( sig ) { + softfloat_f32UIToCommonNaN( uiA, &commonNaN ); + uiZ = softfloat_commonNaNToF64UI( &commonNaN ); + } else { + uiZ = packToF64UI( sign, 0x7FF, 0 ); + } + goto uiZ; + } + if ( ! exp ) { + if ( ! sig ) { + uiZ = packToF64UI( sign, 0, 0 ); + goto uiZ; + } + normExpSig = softfloat_normSubnormalF32Sig( sig ); + exp = normExpSig.exp - 1; + sig = normExpSig.sig; + } + uiZ = packToF64UI( sign, exp + 0x380, (uint_fast64_t) sig<<29 ); + uiZ: + uZ.ui = uiZ; + return uZ.f; + +} + |