| 1 | //===------- bswapdi2 - Implement bswapdi2 --------------------------------===// |
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| 2 | // |
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| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 4 | // See https://llvm.org/LICENSE.txt for license information. |
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| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 6 | // |
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| 7 | //===----------------------------------------------------------------------===// |
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| 8 | |
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| 9 | #include "../assembly.h" |
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| 10 | |
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| 11 | .syntax unified |
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| 12 | .text |
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| 13 | DEFINE_CODE_STATE |
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| 14 | |
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| 15 | // |
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| 16 | // extern uint64_t __bswapdi2(uint64_t); |
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| 17 | // |
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| 18 | // Reverse all the bytes in a 64-bit integer. |
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| 19 | // |
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| 20 | .p2align 2 |
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| 21 | DEFINE_COMPILERRT_FUNCTION(__bswapdi2) |
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| 22 | #if __ARM_ARCH < 6 |
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| 23 | // before armv6 does not have "rev" instruction |
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| 24 | // r2 = rev(r0) |
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| 25 | eor r2, r0, r0, ror #16 |
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| 26 | bic r2, r2, #0xff0000 |
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| 27 | mov r2, r2, lsr #8 |
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| 28 | eor r2, r2, r0, ror #8 |
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| 29 | // r0 = rev(r1) |
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| 30 | eor r0, r1, r1, ror #16 |
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| 31 | bic r0, r0, #0xff0000 |
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| 32 | mov r0, r0, lsr #8 |
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| 33 | eor r0, r0, r1, ror #8 |
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| 34 | #else |
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| 35 | rev r2, r0 // r2 = rev(r0) |
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| 36 | rev r0, r1 // r0 = rev(r1) |
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| 37 | #endif |
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| 38 | mov r1, r2 // r1 = r2 = rev(r0) |
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| 39 | JMP(lr) |
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| 40 | END_COMPILERRT_FUNCTION(__bswapdi2) |
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| 41 | |
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| 42 | NO_EXEC_STACK_DIRECTIVE |
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| 43 | |
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| 44 | |
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