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//===-- floatundixf.c - Implement __floatundixf ---------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements __floatundixf for the compiler_rt library.
//
//===----------------------------------------------------------------------===//
#if !_ARCH_PPC
#include "int_lib.h"
// Returns: convert a to a long double, rounding toward even.
// Assumption: long double is a IEEE 80 bit floating point type padded to 128 bits
// du_int is a 64 bit integral type
// gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee eeee |
// 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm
long double
__floatundixf(du_int a)
{
if (a == 0)
return 0.0;
const unsigned N = sizeof(du_int) * CHAR_BIT;
int clz = __builtin_clzll(a);
int e = (N - 1) - clz ; // exponent
long_double_bits fb;
fb.u.high.low = (e + 16383); // exponent
fb.u.low.all = a << clz; // mantissa
return fb.f;
}
#endif
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