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//===------- bswapsi2 - Implement bswapsi2 --------------------------------===//
//
//                     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.
//
//===----------------------------------------------------------------------===//

#include "../assembly.h"

	.syntax unified
	.text
#if __ARM_ARCH_ISA_THUMB == 2
	.thumb
#endif

//
// extern uint32_t __bswapsi2(uint32_t);
//
// Reverse all the bytes in a 32-bit integer.
//
	.p2align 2
#if __ARM_ARCH_ISA_THUMB == 2
DEFINE_COMPILERRT_THUMB_FUNCTION(__bswapsi2)
#else
DEFINE_COMPILERRT_FUNCTION(__bswapsi2)
#endif
#if __ARM_ARCH < 6
    // before armv6 does not have "rev" instruction
 	eor	r1, r0, r0, ror #16
 	bic	r1, r1, #0xff0000
 	mov	r1, r1, lsr #8
 	eor	r0, r1, r0, ror #8
#else
    rev r0, r0
#endif
    JMP(lr)
END_COMPILERRT_FUNCTION(__bswapsi2)

NO_EXEC_STACK_DIRECTIVE