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//===-- lib/fixdfsi.c - Double-precision -> integer conversion ----*- C -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements float to integer conversion for the
// compiler-rt library.
//
//===----------------------------------------------------------------------===//
#include "fp_lib.h"
static __inline fixint_t __fixint(fp_t a) {
const fixint_t fixint_max = (fixint_t)((~(fixuint_t)0) / 2);
const fixint_t fixint_min = -fixint_max - 1;
// Break a into sign, exponent, significand
const rep_t aRep = toRep(a);
const rep_t aAbs = aRep & absMask;
const fixint_t sign = aRep & signBit ? -1 : 1;
const int exponent = (aAbs >> significandBits) - exponentBias;
const rep_t significand = (aAbs & significandMask) | implicitBit;
// If exponent is negative, the result is zero.
if (exponent < 0)
return 0;
// If the value is too large for the integer type, saturate.
if ((unsigned)exponent >= sizeof(fixint_t) * CHAR_BIT)
return sign == 1 ? fixint_max : fixint_min;
// If 0 <= exponent < significandBits, right shift to get the result.
// Otherwise, shift left.
if (exponent < significandBits)
return sign * (significand >> (significandBits - exponent));
else
return sign * ((fixint_t)significand << (exponent - significandBits));
}
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