hanchenye-llvm-project/compiler-rt/lib/powidf2.c

34 lines
785 B
C

//===-- powidf2.cpp - Implement __powidf2 ---------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __powidf2 for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#include "int_lib.h"
// Returns: a ^ b
double
__powidf2(double a, si_int b)
{
const int recip = b < 0;
double r = 1;
while (1)
{
if (b & 1)
r *= a;
b /= 2;
if (b == 0)
break;
a *= a;
}
return recip ? 1/r : r;
}