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 .syntax unified 13 .text 14 #if __ARM_ARCH_ISA_THUMB == 2 15 .thumb 16 #endif 17 18 // 19 // extern uint32_t __bswapsi2(uint32_t); 20 // 21 // Reverse all the bytes in a 32-bit integer. 22 // 23 .p2align 2 24 #if __ARM_ARCH_ISA_THUMB == 2 25 DEFINE_COMPILERRT_THUMB_FUNCTION(__bswapsi2) 26 #else 27 DEFINE_COMPILERRT_FUNCTION(__bswapsi2) 28 #endif 29 #if __ARM_ARCH < 6 30 // before armv6 does not have "rev" instruction 31 eor r1, r0, r0, ror #16 32 bic r1, r1, #0xff0000 33 mov r1, r1, lsr #8 34 eor r0, r1, r0, ror #8 35 #else 36 rev r0, r0 37 #endif 38 JMP(lr) 39 END_COMPILERRT_FUNCTION(__bswapsi2) 40 41 NO_EXEC_STACK_DIRECTIVE 42 43
