[flang-commits] [flang] FIR TBAA Pass (PR #68414)

[Slava Zakharin via flang-commits]

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@@ -0,0 +1,104 @@
+//===-- TBAAForest.h - A TBAA tree for each function -----------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef FORTRAN_OPTIMIZER_ANALYSIS_TBAA_FOREST_H
+#define FORTRAN_OPTIMIZER_ANALYSIS_TBAA_FOREST_H
+
+#include "mlir/Dialect/Func/IR/FuncOps.h"
+#include "mlir/Dialect/LLVMIR/LLVMAttrs.h"
+#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
+#include "mlir/IR/MLIRContext.h"
+#include "llvm/ADT/DenseMap.h"
+#include <string>
+
+namespace fir {
+
+//===----------------------------------------------------------------------===//
+// TBAATree
+//===----------------------------------------------------------------------===//
+/// Per-function TBAA tree. Each tree contins branches for data (of various
+/// kinds) and descriptor access
+struct TBAATree {
+  //===----------------------------------------------------------------------===//
+  // TBAAForrest::TBAATree::SubtreeState
+  //===----------------------------------------------------------------------===//
+  /// This contains a TBAA subtree based on some parent. New tags can be added
+  /// under the parent using getTag.
+  class SubtreeState {
+    friend TBAATree; // only allow construction by TBAATree
+  public:
+    SubtreeState() = delete;
+    SubtreeState(const SubtreeState &) = delete;
+    SubtreeState(SubtreeState &&) = default;
+
+    mlir::LLVM::TBAATagAttr getTag(llvm::StringRef uniqueId) const;
+
+  private:
+    SubtreeState(mlir::MLIRContext *ctx, std::string name,
+                 mlir::LLVM::TBAANodeAttr grandParent)
+        : parentId{std::move(name)}, context(ctx) {
+      parent = mlir::LLVM::TBAATypeDescriptorAttr::get(
+          context, parentId, mlir::LLVM::TBAAMemberAttr::get(grandParent, 0));
+    }
+
+    const std::string parentId;
+    mlir::MLIRContext *const context;
+    mlir::LLVM::TBAATypeDescriptorAttr parent;
+    llvm::DenseMap<llvm::StringRef, mlir::LLVM::TBAATagAttr> tagDedup;
+  };
+
+  SubtreeState globalDataTree;
+  SubtreeState allocatedDataTree;
+  SubtreeState dummyArgDataTree;
+  mlir::LLVM::TBAATypeDescriptorAttr anyAccessDesc;
+  mlir::LLVM::TBAATypeDescriptorAttr boxMemberTypeDesc;
+  mlir::LLVM::TBAATypeDescriptorAttr anyDataTypeDesc;
+
+  static TBAATree buildTree(mlir::StringAttr functionName);
+
+private:
+  TBAATree(mlir::LLVM::TBAATypeDescriptorAttr anyAccess,
+           mlir::LLVM::TBAATypeDescriptorAttr dataRoot,
+           mlir::LLVM::TBAATypeDescriptorAttr boxMemberTypeDesc);
+};
+
+//===----------------------------------------------------------------------===//
+// TBAAForrest
+//===----------------------------------------------------------------------===//
+/// Colletion of TBAATrees, usually indexed by function (so that each function
----------------
vzakhari wrote:

```suggestion
/// Collection of TBAATrees, usually indexed by function (so that each function
```

https://github.com/llvm/llvm-project/pull/68414