[flang] [llvm] [Flang] Adding lowering for the allocation and deallocation of coarrays (PR #182110)

[via llvm-commits]

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@@ -884,13 +908,32 @@ genDeallocate(fir::FirOpBuilder &builder,
               Fortran::lower::AbstractConverter &converter, mlir::Location loc,
               const fir::MutableBoxValue &box, ErrorManager &errorManager,
               mlir::Value declaredTypeDesc = {},
-              const Fortran::semantics::Symbol *symbol = nullptr) {
+              const Fortran::semantics::Symbol *symbol = nullptr,
+              const Fortran::lower::SomeExpr *allocExpr = nullptr) {
   bool isCudaSymbol = symbol && Fortran::semantics::HasCUDAAttr(*symbol);
   bool isCudaDeviceContext = cuf::isCUDADeviceContext(builder.getRegion());
   bool inlineDeallocation =
       !box.isDerived() && !box.isPolymorphic() && !box.hasAssumedRank() &&
       !box.isUnlimitedPolymorphic() && !errorManager.hasStatSpec() &&
       !useAllocateRuntime && !box.isPointer();
+
+  std::optional<Fortran::evaluate::DataRef> dataRef =
+      !allocExpr ? std::nullopt : Fortran::evaluate::ExtractDataRef(allocExpr);
+  bool isCoarraySymbol = symbol && Fortran::evaluate::IsCoarray(*symbol);
+
+  // Deallocate coarray
+  if (isCoarraySymbol) {
+    mlir::Value ret = builder.createTemporary(loc, builder.getI32Type());
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jeanPerier wrote:

I think the handling of STAT here will cause the code to silently continue after an issue with coarray ALLOCATE when neither STAT/ERRMSG are present.

With the normal runtime, the runtime is provided a boolean telling it if STAT is present, and will terminate the program if an issue is met and this boolean is false and errmsg was not provided.

I would advise doing something similar, or passing the stat variable directly/ a nullptr if not present (but this last approach is made more difficult by the fact that stat may have any integer KIND, so you would need a descriptor, hence the approach of using a bool argument + i32 return of _FortranAAllocatableAllocate).


https://github.com/llvm/llvm-project/pull/182110