[flang-commits] [flang] [mlir] [mlir][OpenMP][flang] make private variable allocation implicit in omp.private (PR #124019)

[Tom Eccles via flang-commits]

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@@ -371,13 +426,15 @@ void Fortran::lower::omp::populateByRefInitAndCleanupRegions(
   }
 
   if (fir::isa_derived(ty)) {
-    if (needsInitialization) {
-      builder.setInsertionPointToStart(initBlock);
-      mlir::Type boxedTy = fir::BoxType::get(ty);
-      mlir::Value box =
-          builder.create<fir::EmboxOp>(loc, boxedTy, allocatedPrivVarArg);
-      fir::runtime::genDerivedTypeInitialize(builder, loc, box);
-    }
+    builder.setInsertionPointToStart(initBlock);
+    mlir::Type boxedTy = fir::BoxType::get(ty);
+    mlir::Value newBox =
+        builder.create<fir::EmboxOp>(loc, boxedTy, allocatedPrivVarArg);
+    mlir::Value moldBox = builder.create<fir::EmboxOp>(loc, boxedTy, moldArg);
+    initializeIfDerivedTypeBox(
+        builder, loc, newBox, moldBox, needsInitialization,
+        /*isFirstPrivate=*/kind == DeclOperationKind::FirstPrivate);
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tblah wrote:

Agreed. It is even worse than just derived types, we load `moldArg` to fetch the length parameters whether or not there really are any. That load (and probably these embox operations) get removed by DCE but not before the barriers are created.

https://github.com/llvm/llvm-project/pull/124019