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- /* ===-- divsi3.c - Implement __divsi3 -------------------------------------===
- *
- * The LLVM Compiler Infrastructure
- *
- * This file is dual licensed under the MIT and the University of Illinois Open
- * Source Licenses. See LICENSE.TXT for details.
- *
- * ===----------------------------------------------------------------------===
- *
- * This file implements __divsi3 for the compiler_rt library.
- *
- * ===----------------------------------------------------------------------===
- */
- #include "int_lib.h"
- /* Returns: a / b */
- ARM_EABI_FNALIAS(idiv, divsi3)
- COMPILER_RT_ABI si_int
- __divsi3(si_int a, si_int b)
- {
- const int bits_in_word_m1 = (int)(sizeof(si_int) * CHAR_BIT) - 1;
- si_int s_a = a >> bits_in_word_m1; /* s_a = a < 0 ? -1 : 0 */
- si_int s_b = b >> bits_in_word_m1; /* s_b = b < 0 ? -1 : 0 */
- a = (a ^ s_a) - s_a; /* negate if s_a == -1 */
- b = (b ^ s_b) - s_b; /* negate if s_b == -1 */
- s_a ^= s_b; /* sign of quotient */
- /*
- * On CPUs without unsigned hardware division support,
- * this calls __udivsi3 (notice the cast to su_int).
- * On CPUs with unsigned hardware division support,
- * this uses the unsigned division instruction.
- */
- return ((su_int)a/(su_int)b ^ s_a) - s_a; /* negate if s_a == -1 */
- }
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