1 /* ===-- fixunssfdi.c - Implement __fixunssfdi -----------------------------=== 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 __fixunssfdi for the compiler_rt library. 11 * 12 * ===----------------------------------------------------------------------=== 13 */ 14 15 #include "int_lib.h" 16 17 /* Returns: convert a to a unsigned long long, rounding toward zero. 18 * Negative values all become zero. 19 */ 20 21 /* Assumption: float is a IEEE 32 bit floating point type 22 * du_int is a 64 bit integral type 23 * value in float is representable in du_int or is negative 24 * (no range checking performed) 25 */ 26 27 /* seee eeee emmm mmmm mmmm mmmm mmmm mmmm */ 28 29 du_int 30 __fixunssfdi(float a) 31 { 32 float_bits fb; 33 fb.f = a; 34 int e = ((fb.u & 0x7F800000) >> 23) - 127; 35 if (e < 0 || (fb.u & 0x80000000)) 36 return 0; 37 du_int r = (fb.u & 0x007FFFFF) | 0x00800000; 38 if (e > 23) 39 r <<= (e - 23); 40 else 41 r >>= (23 - e); 42 return r; 43 } 44