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[Unwind][AArch64] Match sigreturn instructions in big endian (#167139)

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Since insns are always stored LE, on a BE system the opcodes will be
loaded byte-reversed. Therefore, define two sets of opcodes, one for LE
and one for BE.
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hstk30-hw 2025-11-15 09:37:15 +08:00 committed by GitHub
parent 9036e2359f
commit 6214dccbc9
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1 changed files with 16 additions and 1 deletions
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17
libunwind/src/UnwindCursor.hpp
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@ -2865,6 +2865,21 @@ void UnwindCursor<A, R>::setInfoBasedOnIPRegister(bool isReturnAddress) {
#if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN) && \
defined(_LIBUNWIND_TARGET_AARCH64)
/*
* The linux sigreturn restorer stub will always have the form:
*
* d2801168 movz x8, #0x8b
* d4000001 svc #0x0
*/
#if defined(__AARCH64EB__)
#define MOVZ_X8_8B 0x681180d2
#define SVC_0 0x010000d4
#else
#define MOVZ_X8_8B 0xd2801168
#define SVC_0 0xd4000001
#endif
template <typename A, typename R>
bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_arm64 &) {
// Look for the sigreturn trampoline. The trampoline's body is two
@ -2889,7 +2904,7 @@ bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_arm64 &) {
return false;
auto *instructions = reinterpret_cast<const uint32_t *>(pc);
// Look for instructions: mov x8, #0x8b; svc #0x0
if (instructions[0] != 0xd2801168 || instructions[1] != 0xd4000001)
if (instructions[0] != MOVZ_X8_8B || instructions[1] != SVC_0)
return false;
_info = {};