llvm-project

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//===-- absvsi2.c - Implement __absvsi2 -----------------------------------===//
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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 __absvsi2 for the compiler_rt library.
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//
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//===----------------------------------------------------------------------===//
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#include "int_lib.h"
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// Returns: absolute value
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// Effects: aborts if abs(x) < 0
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COMPILER_RT_ABI si_int __absvsi2(si_int a) {
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  const int N = (int)(sizeof(si_int) * CHAR_BIT);
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  if (a == ((si_int)((su_int)1 << (N - 1))))
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    compilerrt_abort();
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  const si_int t = a >> (N - 1);
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  return (a ^ t) - t;
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}
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