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/*===-- divsi3.S - 32-bit signed integer divide ---------------------------===//
* 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 the __divsi3 (32-bit signed integer divide) function
* for the ARM architecture as a wrapper around the unsigned routine.
#include "../assembly.h"
push {r4, r7, lr} ;\
add r7, sp, #4
pop {r4, r7, pc}
.syntax unified
.p2align 3
// Ok, APCS and AAPCS agree on 32 bit args, so it's safe to use the same routine.
DEFINE_AEABI_FUNCTION_ALIAS(__aeabi_idiv, __divsi3)
@ int __divsi3(int divident, int divisor)
@ Calculate and return the quotient of the (signed) division.
tst r1,r1
beq LOCAL_LABEL(divzero)
sdiv r0, r0, r1
bx lr
mov r0,#0
bx lr
// Set aside the sign of the quotient.
# if __ARM_ARCH_ISA_THUMB == 1
movs r4, r0
eors r4, r1
# else
eor r4, r0, r1
# endif
// Take absolute value of a and b via abs(x) = (x^(x >> 31)) - (x >> 31).
# if __ARM_ARCH_ISA_THUMB == 1
asrs r2, r0, #31
asrs r3, r1, #31
eors r0, r2
eors r1, r3
subs r0, r0, r2
subs r1, r1, r3
# else
eor r2, r0, r0, asr #31
eor r3, r1, r1, asr #31
sub r0, r2, r0, asr #31
sub r1, r3, r1, asr #31
# endif
// abs(a) / abs(b)
bl SYMBOL_NAME(__udivsi3)
// Apply sign of quotient to result and return.
# if __ARM_ARCH_ISA_THUMB == 1
asrs r4, #31
eors r0, r4
subs r0, r0, r4
# else
eor r0, r0, r4, asr #31
sub r0, r0, r4, asr #31
# endif