[compiler-rt] [win/asan] GetInstructionSize: Support `48 bX` movabsq instructions. (PR #141625)

[Farzon Lotfi via llvm-commits]

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@@ -754,6 +754,12 @@ static size_t GetInstructionSize(uptr address, size_t* rel_offset = nullptr) {
     case 0x7B81:  // 81 7B YY XX XX XX XX  cmp DWORD PTR [rbx+YY], XX XX XX XX
     case 0x7981:  // 81 79 YY XX XX XX XX  cmp dword ptr [rcx+YY], XX XX XX XX
       return 7;
+
+    case 0xb848:  // 48 b8 XX XX XX XX XX XX XX XX :
+                  //   movabsq XX XX XX XX XX XX XX XX, rax
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farzonl wrote:

Are these moves used for 32bit instructions? should we add a `eax` and `edx` version ?

https://github.com/llvm/llvm-project/pull/141625