1 /*===-- moddi3.c - Implement __moddi3 -------------------------------------=== 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 __moddi3 for the compiler_rt library. 11 * 12 * ===----------------------------------------------------------------------=== 13 */ 14 15 #include "int_lib.h" 16 17 /* Returns: a % b */ 18 19 COMPILER_RT_ABI di_int 20 __moddi3(di_int a, di_int b) 21 { 22 const int bits_in_dword_m1 = (int)(sizeof(di_int) * CHAR_BIT) - 1; 23 di_int s = b >> bits_in_dword_m1; /* s = b < 0 ? -1 : 0 */ 24 b = (b ^ s) - s; /* negate if s == -1 */ 25 s = a >> bits_in_dword_m1; /* s = a < 0 ? -1 : 0 */ 26 a = (a ^ s) - s; /* negate if s == -1 */ 27 du_int r; 28 __udivmoddi4(a, b, &r); 29 return ((di_int)r ^ s) - s; /* negate if s == -1 */ 30 } 31
