35 lines
820 B
C
35 lines
820 B
C
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/* ===-- powidf2.cpp - Implement __powidf2 ---------------------------------===
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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 __powidf2 for the compiler_rt library.
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*
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* ===----------------------------------------------------------------------===
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*/
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#include "int_lib.h"
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/* Returns: a ^ b */
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COMPILER_RT_ABI double
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__powidf2(double a, si_int b)
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{
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const int recip = b < 0;
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double r = 1;
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while (1)
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{
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if (b & 1)
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r *= a;
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b /= 2;
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if (b == 0)
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break;
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a *= a;
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}
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return recip ? 1/r : r;
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}
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