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Diffstat (limited to 'source/ui64_to_f32.c')
-rw-r--r-- | source/ui64_to_f32.c | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/source/ui64_to_f32.c b/source/ui64_to_f32.c new file mode 100644 index 0000000..4de3d13 --- /dev/null +++ b/source/ui64_to_f32.c @@ -0,0 +1,61 @@ + +/*============================================================================ + +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 <stdint.h> +#include "platform.h" +#include "internals.h" +#include "softfloat.h" + +float32_t ui64_to_f32( uint64_t a ) +{ + int_fast8_t shiftCount; + union ui32_f32 u; + uint_fast32_t sig; + + shiftCount = softfloat_countLeadingZeros64( a ) - 40; + if ( 0 <= shiftCount ) { + u.ui = + a ? packToF32UI( + 0, 0x95 - shiftCount, (uint_fast32_t) a<<shiftCount ) + : 0; + return u.f; + } else { + shiftCount += 7; + sig = + (shiftCount < 0) ? softfloat_shortShiftRightJam64( a, -shiftCount ) + : (uint_fast32_t) a<<shiftCount; + return softfloat_roundPackToF32( 0, 0x9C - shiftCount, sig ); + } + +} + |