[flang-commits] [flang] [flang] Added fir.create_box operation. (PR #210220)

[via flang-commits]

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@@ -2821,6 +2821,68 @@ mlir::Speculation::Speculatability fir::EmboxOp::getSpeculatability() {
              : mlir::Speculation::Speculatable;
 }
 
+//===----------------------------------------------------------------------===//
+// CreateBoxOp
+//===----------------------------------------------------------------------===//
+
+unsigned fir::CreateBoxOp::getRank() {
+  auto boxTy = mlir::cast<fir::BaseBoxType>(getResult().getType());
+  if (auto seqTy = mlir::dyn_cast<fir::SequenceType>(
+          fir::unwrapRefType(boxTy.getEleTy())))
+    return seqTy.getDimension();
+  return 0;
+}
+
+llvm::LogicalResult fir::CreateBoxOp::verify() {
+  auto memEleTy = fir::dyn_cast_ptrEleTy(getMemref().getType());
+  auto seqTy = mlir::dyn_cast_or_null<fir::SequenceType>(memEleTy);
+  if (!seqTy)
+    return emitOpError("memref must be a reference to an array");
+
+  auto boxTy = mlir::cast<fir::BaseBoxType>(getResult().getType());
+  auto boxSeqTy =
+      mlir::dyn_cast<fir::SequenceType>(fir::unwrapRefType(boxTy.getEleTy()));
+  if (!boxSeqTy)
+    return emitOpError("result box must describe an array");
+
+  // The result box must preserve the memref's storage kind so that the
+  // descriptor's CFI attribute field is set correctly and the value matches a
+  // box loaded from the corresponding !fir.ref<!fir.box<...>>:
+  //   !fir.heap<...> -> !fir.box<!fir.heap<...>> (allocatable)
+  //   !fir.ptr<...>  -> !fir.box<!fir.ptr<...>>  (pointer)
+  //   !fir.ref<...>  -> !fir.box<...>            (plain)
+  mlir::Type memrefTy = getMemref().getType();
+  mlir::Type boxEleTy = boxTy.getEleTy();
+  if (mlir::isa<fir::HeapType>(memrefTy) !=
+          mlir::isa<fir::HeapType>(boxEleTy) ||
+      mlir::isa<fir::PointerType>(memrefTy) !=
+          mlir::isa<fir::PointerType>(boxEleTy))
+    return emitOpError(
+        "result box element storage kind must match the memref storage kind");
----------------
jeanPerier wrote:

Maybe it is worth also calling `verifyEmboxOpVolatilityInvariants` here to enforce volatile aspects are not dropped.

https://github.com/llvm/llvm-project/pull/210220