| 1 | //===------- bswapsi2 - Implement bswapsi2 --------------------------------===// |
| 2 | // |
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #include "../assembly.h" |
| 10 | |
| 11 | .syntax unified |
| 12 | .text |
| 13 | DEFINE_CODE_STATE |
| 14 | |
| 15 | // |
| 16 | // extern uint32_t __bswapsi2(uint32_t); |
| 17 | // |
| 18 | // Reverse all the bytes in a 32-bit integer. |
| 19 | // |
| 20 | .p2align 2 |
| 21 | DEFINE_COMPILERRT_FUNCTION(__bswapsi2) |
| 22 | #if __ARM_ARCH < 6 |
| 23 | // before armv6 does not have "rev" instruction |
| 24 | eor r1, r0, r0, ror #16 |
| 25 | bic r1, r1, #0xff0000 |
| 26 | mov r1, r1, lsr #8 |
| 27 | eor r0, r1, r0, ror #8 |
| 28 | #else |
| 29 | rev r0, r0 |
| 30 | #endif |
| 31 | JMP(lr) |
| 32 | END_COMPILERRT_FUNCTION(__bswapsi2) |
| 33 | |
| 34 | NO_EXEC_STACK_DIRECTIVE |
| 35 | |
| 36 | |