[flang-commits] [flang] [flang] Characterize allocation based on MemAlloc effect instead of pattern matching (PR #166806)

[Slava Zakharin via flang-commits]

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@@ -285,6 +285,21 @@ llvm::LogicalResult fir::AllocaOp::verify() {
   return mlir::success();
 }
 
+void fir::AllocaOp::getEffects(
+    llvm::SmallVectorImpl<
+        mlir::SideEffects::EffectInstance<mlir::MemoryEffects::Effect>>
+        &effects) {
+  // Value-scoped Allocate for AA.
+  effects.emplace_back(
+      mlir::MemoryEffects::Allocate::get(),
+      mlir::cast<mlir::OpResult>(getOperation()->getResult(0)),
+      mlir::SideEffects::AutomaticAllocationScopeResource::get());
+  // Preserve previous behavior: op-scoped Allocate for passes relying on it.
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vzakhari wrote:

I think we do not need this here and for `AllocMemOp`.  Did you find any LIT tests that fail without this?

I believe the effect above implies the effect that you are adding below. If it is not the case I am interested to see an example that fails.

https://github.com/llvm/llvm-project/pull/166806