Fix StructType::isScalableTy by calling back into Type::isScalableTy

Author: jayfoad

llvm/lib/IR/Type.cpp

@@ -408,18 +408,11 @@ bool StructType::isScalableTy(SmallPtrSetImpl<Type *> &Visited) const {
     return false;
 
   for (Type *Ty : elements()) {
-    if (isa<ScalableVectorType>(Ty)) {
+    if (Ty->isScalableTy(Visited)) {
       const_cast<StructType *>(this)->setSubclassData(
           getSubclassData() | SCDB_ContainsScalableVector);
       return true;
     }
-    if (auto *STy = dyn_cast<StructType>(Ty)) {
-      if (STy->isScalableTy(Visited)) {
-        const_cast<StructType *>(this)->setSubclassData(
-            getSubclassData() | SCDB_ContainsScalableVector);
-        return true;
-      }
-    }
   }
 
   // For structures that are opaque, return false but do not set the

llvm/test/Verifier/scalable-global-vars.ll

@@ -15,3 +15,17 @@
 ; CHECK-NEXT: ptr @ScalableVecStructGlobal
 @ScalableVecStructGlobal = global { i32,  <vscale x 4 x i32> } zeroinitializer
 
+; CHECK-NEXT: Globals cannot contain scalable types
+; CHECK-NEXT: ptr @StructTestGlobal
+%struct.test = type { <vscale x 1 x double>, <vscale x 1 x double> }
+@StructTestGlobal = global %struct.test zeroinitializer
+
+; CHECK-NEXT: Globals cannot contain scalable types
+; CHECK-NEXT: ptr @StructArrayTestGlobal
+%struct.array.test = type { [2 x <vscale x 1 x double>] }
+@StructArrayTestGlobal = global %struct.array.test zeroinitializer
+
+; CHECK-NEXT: Globals cannot contain scalable types
+; CHECK-NEXT: ptr @StructTargetTestGlobal
+%struct.target.test = type { target("aarch64.svcount"), target("aarch64.svcount") }
+@StructTargetTestGlobal = global %struct.target.test zeroinitializer