llvm-project

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//===-- fixunsxfsi.c - Implement __fixunsxfsi -----------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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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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#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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// Assumption: long double is an intel 80 bit floating point type padded with 6
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// bytes su_int is a 32 bit integral type value in long double is representable
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// in su_int or is negative
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// gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee
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// eeee | 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm
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// mmmm mmmm mmmm
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#if defined(_MSC_VER) && !defined(__clang__)
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// MSVC throws a warning about 'uninitialized variable use' here,
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// disable it for builds that warn-as-error
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#pragma warning(push)
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#pragma warning(disable : 4700)
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#endif
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COMPILER_RT_ABI su_int __fixunsxfsi(xf_float a) {
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  xf_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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#if defined(_MSC_VER) && !defined(__clang__)
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#pragma warning(pop)
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#endif
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#endif // !_ARCH_PPC
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