xref: /aosp_15_r20/external/compiler-rt/lib/builtins/arm/bswapsi2.S (revision 7c3d14c8b49c529e04be81a3ce6f5cc23712e4c6)
1*7c3d14c8STreehugger Robot//===------- bswapsi2 - Implement bswapsi2 --------------------------------===//
2*7c3d14c8STreehugger Robot//
3*7c3d14c8STreehugger Robot//                     The LLVM Compiler Infrastructure
4*7c3d14c8STreehugger Robot//
5*7c3d14c8STreehugger Robot// This file is dual licensed under the MIT and the University of Illinois Open
6*7c3d14c8STreehugger Robot// Source Licenses. See LICENSE.TXT for details.
7*7c3d14c8STreehugger Robot//
8*7c3d14c8STreehugger Robot//===----------------------------------------------------------------------===//
9*7c3d14c8STreehugger Robot
10*7c3d14c8STreehugger Robot#include "../assembly.h"
11*7c3d14c8STreehugger Robot
12*7c3d14c8STreehugger Robot	.syntax unified
13*7c3d14c8STreehugger Robot	.text
14*7c3d14c8STreehugger Robot#if __ARM_ARCH_ISA_THUMB == 2
15*7c3d14c8STreehugger Robot	.thumb
16*7c3d14c8STreehugger Robot#endif
17*7c3d14c8STreehugger Robot
18*7c3d14c8STreehugger Robot//
19*7c3d14c8STreehugger Robot// extern uint32_t __bswapsi2(uint32_t);
20*7c3d14c8STreehugger Robot//
21*7c3d14c8STreehugger Robot// Reverse all the bytes in a 32-bit integer.
22*7c3d14c8STreehugger Robot//
23*7c3d14c8STreehugger Robot	.p2align 2
24*7c3d14c8STreehugger Robot#if __ARM_ARCH_ISA_THUMB == 2
25*7c3d14c8STreehugger RobotDEFINE_COMPILERRT_THUMB_FUNCTION(__bswapsi2)
26*7c3d14c8STreehugger Robot#else
27*7c3d14c8STreehugger RobotDEFINE_COMPILERRT_FUNCTION(__bswapsi2)
28*7c3d14c8STreehugger Robot#endif
29*7c3d14c8STreehugger Robot#if __ARM_ARCH < 6
30*7c3d14c8STreehugger Robot    // before armv6 does not have "rev" instruction
31*7c3d14c8STreehugger Robot 	eor	r1, r0, r0, ror #16
32*7c3d14c8STreehugger Robot 	bic	r1, r1, #0xff0000
33*7c3d14c8STreehugger Robot 	mov	r1, r1, lsr #8
34*7c3d14c8STreehugger Robot 	eor	r0, r1, r0, ror #8
35*7c3d14c8STreehugger Robot#else
36*7c3d14c8STreehugger Robot    rev r0, r0
37*7c3d14c8STreehugger Robot#endif
38*7c3d14c8STreehugger Robot    JMP(lr)
39*7c3d14c8STreehugger RobotEND_COMPILERRT_FUNCTION(__bswapsi2)
40*7c3d14c8STreehugger Robot
41*7c3d14c8STreehugger RobotNO_EXEC_STACK_DIRECTIVE
42*7c3d14c8STreehugger Robot
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