bswapsi2.S revision 1.1.1.1 1 //===------- bswapsi2 - Implement bswapsi2 --------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "../assembly.h"
11
12 //
13 // extern uint32_t __bswapsi2(uint32_t);
14 //
15 // Reverse all the bytes in a 32-bit integer.
16 //
17 .align 2
18 DEFINE_COMPILERRT_FUNCTION(__bswapsi2)
19 #if __ARM_ARCH < 6
20 // before armv6 does not have "rev" instruction
21 eor r1, r0, r0, ror #16
22 bic r1, r1, #0xff0000
23 mov r1, r1, lsr #8
24 eor r0, r1, r0, ror #8
25 #else
26 rev r0, r0
27 #endif
28 JMP(lr)
29 END_COMPILERRT_FUNCTION(__bswapsi2)
30