minix/sys/external/bsd/compiler_rt/dist/lib/arm/bswapdi2.S
Lionel Sambuc 4684ddb6aa LLVM Minix changes
- import libcxx
 - reduce targets to the one when compiled as a tools

Change-Id: Iabb8427f80ff8e89463559a28bcb8b4f2bdbc496
2014-07-28 17:05:59 +02:00

36 lines
993 B
ArmAsm

//===------- bswapdi2 - Implement bswapdi2 --------------------------------===//
//
// 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"
//
// extern uint64_t __bswapdi2(uint64_t);
//
// Reverse all the bytes in a 64-bit integer.
//
.align 2
DEFINE_COMPILERRT_FUNCTION(__bswapdi2)
#if __ARM_ARCH_5TEJ__ || __ARM_ARCH_4T__
// before armv6 does not have "rev" instruction
// r2 = rev(r0)
eor r2, r0, r0, ror #16
bic r2, r2, #0xff0000
mov r2, r2, lsr #8
eor r2, r2, r0, ror #8
// r0 = rev(r1)
eor r0, r1, r1, ror #16
bic r0, r0, #0xff0000
mov r0, r0, lsr #8
eor r0, r0, r1, ror #8
#else
rev r2, r0 // r2 = rev(r0)
rev r0, r1 // r0 = rev(r1)
#endif
mov r1, r2 // r1 = r2 = rev(r0)
bx lr