[clang] [CIR] Add support for array constructors (PR #149142)

[Henrich Lauko via cfe-commits]

================
@@ -22,15 +24,97 @@ struct LoweringPreparePass : public LoweringPrepareBase<LoweringPreparePass> {
   void runOnOperation() override;
 
   void runOnOp(Operation *op);
+  void lowerArrayCtor(ArrayCtor op);
 };
 
 } // namespace
 
-void LoweringPreparePass::runOnOp(Operation *op) {}
+void LoweringPreparePass::runOnOp(Operation *op) {
+  if (auto arrayCtor = dyn_cast<ArrayCtor>(op)) {
+    lowerArrayCtor(arrayCtor);
+  }
+}
+
+static void lowerArrayDtorCtorIntoLoop(CIRBaseBuilderTy &builder,
----------------
xlauko wrote:

```suggestion
static void lowerArrayDtorCtorIntoLoop(cir::CIRBaseBuilderTy &builder,
```

https://github.com/llvm/llvm-project/pull/149142