corda/sdk/compiler-rt/divsi3.c
Angie Chinchilla 9441de4c38 Initial release of Intel SGX for Linux.
This release is used in conjunction with the linux-sgx-driver Intial release:
https://github.com/01org/linux-sgx-driver
commit-id: 0e865ce5e6b297a787bcdc12d98bada8174be6d7

Intel-id: 33399

Signed-off-by: Angie Chinchilla <angie.v.chinchilla@intel.com>
2016-06-23 18:51:53 -04:00

38 lines
1.4 KiB
C

/* ===-- 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 */
}