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 #include "int_lib.h" 16 17 #ifdef CRT_HAS_128BIT 18 19 /*Returns: a % b */ 20 21 COMPILER_RT_ABI ti_int 22 __modti3(ti_int a, ti_int b) 23 { 24 const int bits_in_tword_m1 = (int)(sizeof(ti_int) * CHAR_BIT) - 1; 25 ti_int s = b >> bits_in_tword_m1; /* s = b < 0 ? -1 : 0 */ 26 b = (b ^ s) - s; /* negate if s == -1 */ 27 s = a >> bits_in_tword_m1; /* s = a < 0 ? -1 : 0 */ 28 a = (a ^ s) - s; /* negate if s == -1 */ 29 tu_int r; 30 __udivmodti4(a, b, &r); 31 return ((ti_int)r ^ s) - s; /* negate if s == -1 */ 32 } 33 34 #endif /* CRT_HAS_128BIT */ 35