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| //===-- floatdixf.c - Implement __floatdixf -------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements __floatdixf 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 di_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
COMPILER_RT_ABI long double __floatdixf(di_int a) {
if (a == 0)
return 0.0;
const unsigned N = sizeof(di_int) * CHAR_BIT;
const di_int s = a >> (N - 1);
a = (a ^ s) - s;
int clz = __builtin_clzll(a);
int e = (N - 1) - clz; // exponent
long_double_bits fb;
fb.u.high.s.low = ((su_int)s & 0x00008000) | // sign
(e + 16383); // exponent
fb.u.low.all = a << clz; // mantissa
return fb.f;
}
#endif // !_ARCH_PPC
|