1 //===------- bswapdi2 - Implement bswapdi2 --------------------------------===// 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 uint64_t __bswapdi2(uint64_t); 20 // 21 // Reverse all the bytes in a 64-bit integer. 22 // 23 .p2align 2 24 #if __ARM_ARCH_ISA_THUMB == 2 25 DEFINE_COMPILERRT_THUMB_FUNCTION(__bswapdi2) 26 #else 27 DEFINE_COMPILERRT_FUNCTION(__bswapdi2) 28 #endif 29 #if __ARM_ARCH < 6 30 // before armv6 does not have "rev" instruction 31 // r2 = rev(r0) 32 eor r2, r0, r0, ror #16 33 bic r2, r2, #0xff0000 34 mov r2, r2, lsr #8 35 eor r2, r2, r0, ror #8 36 // r0 = rev(r1) 37 eor r0, r1, r1, ror #16 38 bic r0, r0, #0xff0000 39 mov r0, r0, lsr #8 40 eor r0, r0, r1, ror #8 41 #else 42 rev r2, r0 // r2 = rev(r0) 43 rev r0, r1 // r0 = rev(r1) 44 #endif 45 mov r1, r2 // r1 = r2 = rev(r0) 46 JMP(lr) 47 END_COMPILERRT_FUNCTION(__bswapdi2) 48 49 NO_EXEC_STACK_DIRECTIVE 50 51
