ASAN on arm64 windows builds but crashes because SANITIZER_WINDOWS64 is used to do x86_64 instruction parsing

[farzonl]

For context you can build asan for arm64 however it asserts in GetInstructionSize because it can't parse the arm instructions.

SANITIZER_WINDOWS64 as defined should only be used to determine if we are working on a 32bit or 64bit operating system.

llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_platform.h

Lines 114 to 118 in 145a929

	#if defined(_WIN64)
	# define SANITIZER_WINDOWS64 1
	#else
	# define SANITIZER_WINDOWS64 0
	#endif

However, in practice it is being used to parse x86_64 instructions.

llvm-project/compiler-rt/lib/interception/interception_win.cpp

Lines 459 to 486 in 145a929

	static size_t GetInstructionSize(uptr address, size_t* rel_offset = nullptr) {
	#if SANITIZER_WINDOWS64
	if (memcmp((u8*)address, kPrologueWithShortJump1,
	sizeof(kPrologueWithShortJump1)) == 0 ||
	memcmp((u8*)address, kPrologueWithShortJump2,
	sizeof(kPrologueWithShortJump2)) == 0) {
	return 0;
	}
	#endif
	switch (*(u64*)address) {
	case 0x90909090909006EB: // stub: jmp over 6 x nop.
	return 8;
	}
	switch (*(u8*)address) {
	case 0x90: // 90 : nop
	return 1;
	case 0x50: // push eax / rax
	case 0x51: // push ecx / rcx
	case 0x52: // push edx / rdx
	case 0x53: // push ebx / rbx
	case 0x54: // push esp / rsp
	case 0x55: // push ebp / rbp
	case 0x56: // push esi / rsi
	case 0x57: // push edi / rdi
	case 0x5D: // pop ebp / rbp

I put up a patch: here https://reviews.llvm.org/D156839
based on:
farzonl@223ee30

[llvmbot]

@llvm/issue-subscribers-backend-aarch64

[farzonl]

fixed by 5a48a82