[flang-commits] [flang] [mlir] [flang][OpenMP] Allow saving first block of an OMP region for allocas (PR #121886)

[Tom Eccles via flang-commits]

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@@ -345,31 +345,37 @@ findAllocaInsertPoint(llvm::IRBuilderBase &builder,
         allocaInsertPoint = frame.allocaInsertPoint;
         return WalkResult::interrupt();
       });
-  if (walkResult.wasInterrupted())
-    return allocaInsertPoint;
 
   // Otherwise, insert to the entry block of the surrounding function.
-  // If the current IRBuilder InsertPoint is the function's entry, it cannot
-  // also be used for alloca insertion which would result in insertion order
-  // confusion. Create a new BasicBlock for the Builder and use the entry block
-  // for the allocs.
+  if (!walkResult.wasInterrupted()) {
+    llvm::BasicBlock &funcEntryBlock =
+        builder.GetInsertBlock()->getParent()->getEntryBlock();
+    allocaInsertPoint = llvm::OpenMPIRBuilder::InsertPointTy(
+        &funcEntryBlock, funcEntryBlock.getFirstInsertionPt());
+  }
+
+  // If the current IRBuilder insertion block is the same as the alloca
+  // insertion block, it cannot also be used for alloca insertion which would
+  // result in insertion order confusion. Create a new BasicBlock for the
+  // Builder and use the entry block for the allocs.
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tblah wrote:

Shouldn't it be okay so long as the allocas land at the start of the block (as they should be anyway)?

https://github.com/llvm/llvm-project/pull/121886