fixunssfdi.c revision 214152
1214152Sed/* ===-- fixunssfdi.c - Implement __fixunssfdi -----------------------------=== 2214152Sed * 3214152Sed * The LLVM Compiler Infrastructure 4214152Sed * 5222656Sed * This file is distributed under the University of Illinois Open Source 6222656Sed * License. See LICENSE.TXT for details. 7214152Sed * 8214152Sed * ===----------------------------------------------------------------------=== 9214152Sed * 10214152Sed * This file implements __fixunssfdi for the compiler_rt library. 11214152Sed * 12214152Sed * ===----------------------------------------------------------------------=== 13214152Sed */ 14214152Sed 15214152Sed#include "int_lib.h" 16214152Sed 17214152Sed/* Returns: convert a to a unsigned long long, rounding toward zero. 18214152Sed * Negative values all become zero. 19214152Sed */ 20214152Sed 21214152Sed/* Assumption: float is a IEEE 32 bit floating point type 22214152Sed * du_int is a 64 bit integral type 23214152Sed * value in float is representable in du_int or is negative 24214152Sed * (no range checking performed) 25214152Sed */ 26214152Sed 27214152Sed/* seee eeee emmm mmmm mmmm mmmm mmmm mmmm */ 28239138Sandrew 29222656Seddu_int 30222656Sed__fixunssfdi(float a) 31214152Sed{ 32214152Sed float_bits fb; 33214152Sed fb.f = a; 34214152Sed int e = ((fb.u & 0x7F800000) >> 23) - 127; 35214152Sed if (e < 0 || (fb.u & 0x80000000)) 36214152Sed return 0; 37214152Sed du_int r = (fb.u & 0x007FFFFF) | 0x00800000; 38214152Sed if (e > 23) 39214152Sed r <<= (e - 23); 40214152Sed else 41214152Sed r >>= (23 - e); 42214152Sed return r; 43214152Sed} 44214152Sed