fp_fixuint_impl.inc revision 287516
1//===-- lib/fixdfsi.c - Double-precision -> integer conversion ----*- C -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is dual licensed under the MIT and the University of Illinois Open 6// Source Licenses. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements float to unsigned integer conversion for the 11// compiler-rt library. 12// 13//===----------------------------------------------------------------------===// 14 15#include "fp_lib.h" 16 17static inline fixuint_t __fixuint(fp_t a) { 18 // Break a into sign, exponent, significand 19 const rep_t aRep = toRep(a); 20 const rep_t aAbs = aRep & absMask; 21 const int sign = aRep & signBit ? -1 : 1; 22 const int exponent = (aAbs >> significandBits) - exponentBias; 23 const rep_t significand = (aAbs & significandMask) | implicitBit; 24 25 // If either the value or the exponent is negative, the result is zero. 26 if (sign == -1 || exponent < 0) 27 return 0; 28 29 // If the value is too large for the integer type, saturate. 30 if ((unsigned)exponent > sizeof(fixuint_t) * CHAR_BIT) 31 return ~(fixuint_t)0; 32 33 // If 0 <= exponent < significandBits, right shift to get the result. 34 // Otherwise, shift left. 35 if (exponent < significandBits) 36 return significand >> (significandBits - exponent); 37 else 38 return (fixuint_t)significand << (exponent - significandBits); 39} 40