25e141edd2
Refactor float to integer conversion to share the same code. 80bit Intel/PPC long double is excluded due to lacking support for the abstraction. Consistently provide saturation logic. Extend to long double on 128bit IEEE extended platforms. Initial patch with test cases from GuanHong Liu. Reviewed by Steve Canon. Differential Revision: http://reviews.llvm.org/D2804 Pull in r232107 from upstream compiler-rt trunk (by Ed Maste): Use signed int implementation for __fixint Requested by: emaste
46 lines
1.4 KiB
C
46 lines
1.4 KiB
C
/* ===-- fixunsxfsi.c - Implement __fixunsxfsi -----------------------------===
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*
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* The LLVM Compiler Infrastructure
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*
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* This file is dual licensed under the MIT and the University of Illinois Open
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* Source Licenses. See LICENSE.TXT for details.
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*
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* ===----------------------------------------------------------------------===
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*
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* This file implements __fixunsxfsi for the compiler_rt library.
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*
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* ===----------------------------------------------------------------------===
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*/
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#if !_ARCH_PPC
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#include "int_lib.h"
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/* Returns: convert a to a unsigned int, rounding toward zero.
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* Negative values all become zero.
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*/
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/* Assumption: long double is an intel 80 bit floating point type padded with 6 bytes
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* su_int is a 32 bit integral type
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* value in long double is representable in su_int or is negative
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*/
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/* gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee eeee |
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* 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm
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*/
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COMPILER_RT_ABI su_int
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__fixunsxfsi(long double a)
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{
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long_double_bits fb;
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fb.f = a;
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int e = (fb.u.high.s.low & 0x00007FFF) - 16383;
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if (e < 0 || (fb.u.high.s.low & 0x00008000))
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return 0;
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if ((unsigned)e > sizeof(su_int) * CHAR_BIT)
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return ~(su_int)0;
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return fb.u.low.s.high >> (31 - e);
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}
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#endif /* !_ARCH_PPC */
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