[clang] [CIR] Add support for array cleanups (PR #150499)

[Henrich Lauko via cfe-commits]

================
@@ -213,15 +215,23 @@ static void lowerArrayDtorCtorIntoLoop(cir::CIRBaseBuilderTy &builder,
         op->walk([&](cir::CallOp c) { ctorCall = c; });
         assert(ctorCall && "expected ctor call");
 
-        auto one = builder.create<cir::ConstantOp>(
-            loc, ptrDiffTy, cir::IntAttr::get(ptrDiffTy, 1));
-
-        ctorCall->moveAfter(one);
-        ctorCall->setOperand(0, currentElement);
-
-        // Advance pointer and store them to temporary variable
-        auto nextElement =
-            builder.create<cir::PtrStrideOp>(loc, eltTy, currentElement, one);
+        // Array elements get constructed in order but destructed in reverse.
+        cir::PtrStrideOp nextElement;
+        if (isCtor) {
+          mlir::Value stride = builder.getUnsignedInt(loc, 1, sizeTypeSize);
+          ctorCall->moveBefore(stride.getDefiningOp());
+          ctorCall->setOperand(0, currentElement);
+          nextElement = builder.create<cir::PtrStrideOp>(
+              loc, eltTy, currentElement, stride);
----------------
xlauko wrote:

```suggestion
          nextElement = cir::PtrStrideOp::create(
              builder, loc, eltTy, currentElement, stride);
```

https://github.com/llvm/llvm-project/pull/150499