[Asan] Teach FunctionStackPoisoner to filter out struct type with scalable vector type. (#93406)

FunctionStackPoisoner does not serve for `AllocaInst` with scalable
vector type, but it does not filter out struct type with scalable vector
introduced by c8eb535.

Author: yetingk

llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp

@@ -1139,8 +1139,10 @@ struct FunctionStackPoisoner : public InstVisitor<FunctionStackPoisoner> {
   /// Collect Alloca instructions we want (and can) handle.
   void visitAllocaInst(AllocaInst &AI) {
     // FIXME: Handle scalable vectors instead of ignoring them.
-    if (!ASan.isInterestingAlloca(AI) ||
-        isa<ScalableVectorType>(AI.getAllocatedType())) {
+    const Type *AllocaType = AI.getAllocatedType();
+    const auto *STy = dyn_cast<StructType>(AllocaType);
+    if (!ASan.isInterestingAlloca(AI) || isa<ScalableVectorType>(AllocaType) ||
+        (STy && STy->containsHomogeneousScalableVectorTypes())) {
       if (AI.isStaticAlloca()) {
         // Skip over allocas that are present *before* the first instrumented
         // alloca, we don't want to move those around.

llvm/test/Instrumentation/AddressSanitizer/asan-struct-scalable.ll

@@ -0,0 +1,11 @@
+; RUN: opt -passes=asan -disable-output -S %s
+; Check not crash.
+
+define void @test() #0 {
+entry:
+  %t0 = alloca { <vscale x 2 x i32>, <vscale x 2 x i32> }, align 4
+  call void null(ptr null, ptr %t0, i64 0)
+  ret void
+}
+
+attributes #0 = { sanitize_address }