xref: /openbsd-src/gnu/llvm/compiler-rt/lib/builtins/powitf2.c (revision 1f9cb04fc6f537ca6cf5a53c28927340cba218a2)
13cab2bb3Spatrick //===-- powitf2.cpp - Implement __powitf2 ---------------------------------===//
23cab2bb3Spatrick //
33cab2bb3Spatrick // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
43cab2bb3Spatrick // See https://llvm.org/LICENSE.txt for license information.
53cab2bb3Spatrick // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
63cab2bb3Spatrick //
73cab2bb3Spatrick //===----------------------------------------------------------------------===//
83cab2bb3Spatrick //
93cab2bb3Spatrick // This file implements __powitf2 for the compiler_rt library.
103cab2bb3Spatrick //
113cab2bb3Spatrick //===----------------------------------------------------------------------===//
123cab2bb3Spatrick 
13*1f9cb04fSpatrick #define QUAD_PRECISION
14*1f9cb04fSpatrick #include "fp_lib.h"
153cab2bb3Spatrick 
16*1f9cb04fSpatrick #if defined(CRT_HAS_128BIT) && defined(CRT_LDBL_128BIT)
173cab2bb3Spatrick 
183cab2bb3Spatrick // Returns: a ^ b
193cab2bb3Spatrick 
__powitf2(long double a,int b)20*1f9cb04fSpatrick COMPILER_RT_ABI long double __powitf2(long double a, int b) {
213cab2bb3Spatrick   const int recip = b < 0;
223cab2bb3Spatrick   long double r = 1;
233cab2bb3Spatrick   while (1) {
243cab2bb3Spatrick     if (b & 1)
253cab2bb3Spatrick       r *= a;
263cab2bb3Spatrick     b /= 2;
273cab2bb3Spatrick     if (b == 0)
283cab2bb3Spatrick       break;
293cab2bb3Spatrick     a *= a;
303cab2bb3Spatrick   }
313cab2bb3Spatrick   return recip ? 1 / r : r;
323cab2bb3Spatrick }
333cab2bb3Spatrick 
343cab2bb3Spatrick #endif
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