divsi3.c revision 222656
143902Sbrian/* ===-- divsi3.c - Implement __divsi3 -------------------------------------=== 243902Sbrian * 343948Sbrian * The LLVM Compiler Infrastructure 443902Sbrian * 543948Sbrian * This file is dual licensed under the MIT and the University of Illinois Open 643902Sbrian * Source Licenses. See LICENSE.TXT for details. 750476Speter * 843902Sbrian * ===----------------------------------------------------------------------=== 943902Sbrian * 1043902Sbrian * This file implements __divsi3 for the compiler_rt library. 1143902Sbrian * 1243902Sbrian * ===----------------------------------------------------------------------=== 1343902Sbrian */ 1443902Sbrian#include "abi.h" 1543902Sbrian 1643902Sbrian#include "int_lib.h" 1743902Sbrian 1843902Sbriansu_int COMPILER_RT_ABI __udivsi3(su_int n, su_int d); 1943902Sbrian 2043902Sbrian/* Returns: a / b */ 2143948Sbrian 2243902SbrianARM_EABI_FNALIAS(idiv, divsi3); 2343902Sbrian 2443948SbrianCOMPILER_RT_ABI si_int 2543948Sbrian__divsi3(si_int a, si_int b) 2643902Sbrian{ 2743902Sbrian const int bits_in_word_m1 = (int)(sizeof(si_int) * CHAR_BIT) - 1; 2843902Sbrian si_int s_a = a >> bits_in_word_m1; /* s_a = a < 0 ? -1 : 0 */ 2943902Sbrian si_int s_b = b >> bits_in_word_m1; /* s_b = b < 0 ? -1 : 0 */ 3043902Sbrian a = (a ^ s_a) - s_a; /* negate if s_a == -1 */ 3143948Sbrian b = (b ^ s_b) - s_b; /* negate if s_b == -1 */ 3243948Sbrian s_a ^= s_b; /* sign of quotient */ 3343902Sbrian return (__udivsi3(a, b) ^ s_a) - s_a; /* negate if s_a == -1 */ 3443902Sbrian} 3543902Sbrian