| //===-- 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)); |
| } |
