1 /* ===-- fixsfdi.c - Implement __fixsfdi -----------------------------------=== 2 * 3 * The LLVM Compiler Infrastructure 4 * 5 * This file is distributed under the University of Illinois Open Source 6 * License. See LICENSE.TXT for details. 7 * 8 * ===----------------------------------------------------------------------=== 9 * 10 * This file implements __fixsfdi for the compiler_rt library. 11 * 12 * ===----------------------------------------------------------------------=== 13 */ 14 15 #include "int_lib.h" 16 17 /* Returns: convert a to a signed long long, rounding toward zero. */ 18 19 /* Assumption: float is a IEEE 32 bit floating point type 20 * su_int is a 32 bit integral type 21 * value in float is representable in di_int (no range checking performed) 22 */ 23 24 /* seee eeee emmm mmmm mmmm mmmm mmmm mmmm */ 25 26 di_int 27 __fixsfdi(float a) 28 { 29 float_bits fb; 30 fb.f = a; 31 int e = ((fb.u & 0x7F800000) >> 23) - 127; 32 if (e < 0) 33 return 0; 34 di_int s = (si_int)(fb.u & 0x80000000) >> 31; 35 di_int r = (fb.u & 0x007FFFFF) | 0x00800000; 36 if (e > 23) 37 r <<= (e - 23); 38 else 39 r >>= (23 - e); 40 return (r ^ s) - s; 41 } 42