[compiler-rt] [win/asan] Add a test skeleton for function GetInstructionSize. (PR #116948)

[via llvm-commits]

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@@ -793,6 +793,38 @@ TEST(Interception, EmptyExportTable) {
   EXPECT_EQ(0U, FunPtr);
 }
 
+const struct InstructionSizeData_t {
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zmodem wrote:

I think just `InstructionSizeData` would be more common in llvm style

https://github.com/llvm/llvm-project/pull/116948