forked from OSchip/llvm-project
40 lines
1.3 KiB
ArmAsm
40 lines
1.3 KiB
ArmAsm
![]() |
/*===-- 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"
|
||
|
|
||
|
#define ESTABLISH_FRAME \
|
||
|
push {r4, r7, lr} ;\
|
||
|
add r7, sp, #4
|
||
|
#define CLEAR_FRAME_AND_RETURN \
|
||
|
pop {r4, r7, pc}
|
||
|
|
||
|
.syntax unified
|
||
|
.align 3
|
||
|
DEFINE_COMPILERRT_FUNCTION(__divsi3)
|
||
|
ESTABLISH_FRAME
|
||
|
// Set aside the sign of the quotient.
|
||
|
eor r4, r0, r1
|
||
|
// Take absolute value of a and b via abs(x) = (x^(x >> 31)) - (x >> 31).
|
||
|
eor r2, r0, r0, asr #31
|
||
|
eor r3, r1, r1, asr #31
|
||
|
sub r0, r2, r0, asr #31
|
||
|
sub r1, r3, r1, asr #31
|
||
|
// abs(a) / abs(b)
|
||
|
bl ___udivsi3
|
||
|
// Apply sign of quotient to result and return.
|
||
|
eor r0, r0, r4, asr #31
|
||
|
sub r0, r0, r4, asr #31
|
||
|
CLEAR_FRAME_AND_RETURN
|