1 /* ===-- modti3.c - Implement __modti3 -------------------------------------=== 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 __modti3 for the compiler_rt library. 11 * 12 * ===----------------------------------------------------------------------=== 13 */ 14 15 #if __x86_64 16 17 #include "int_lib.h" 18 19 tu_int __udivmodti4(tu_int a, tu_int b, tu_int* rem); 20 21 /*Returns: a % b */ 22 23 ti_int 24 __modti3(ti_int a, ti_int b) 25 { 26 const int bits_in_tword_m1 = (int)(sizeof(ti_int) * CHAR_BIT) - 1; 27 ti_int s = b >> bits_in_tword_m1; /* s = b < 0 ? -1 : 0 */ 28 b = (b ^ s) - s; /* negate if s == -1 */ 29 s = a >> bits_in_tword_m1; /* s = a < 0 ? -1 : 0 */ 30 a = (a ^ s) - s; /* negate if s == -1 */ 31 ti_int r; 32 __udivmodti4(a, b, (tu_int*)&r); 33 return (r ^ s) - s; /* negate if s == -1 */ 34 } 35 36 #endif 37
