[flang-commits] [flang] [flang] Use fir.declare/fir.dummy_scope for TBAA tags attachments. (PR #92472)

[Slava Zakharin via flang-commits]

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@@ -54,24 +56,85 @@ namespace {
 /// Shared state per-module
 class PassState {
 public:
+  PassState(mlir::DominanceInfo &domInfo) : domInfo(domInfo) {}
   /// memoised call to fir::AliasAnalysis::getSource
   inline const fir::AliasAnalysis::Source &getSource(mlir::Value value) {
     if (!analysisCache.contains(value))
-      analysisCache.insert({value, analysis.getSource(value)});
+      analysisCache.insert(
+          {value, analysis.getSource(value, /*getInstantiationPoint=*/true)});
     return analysisCache[value];
   }
 
   /// get the per-function TBAATree for this function
   inline const fir::TBAATree &getFuncTree(mlir::func::FuncOp func) {
     return forrest[func];
   }
+  inline const fir::TBAATree &getFuncTreeWithScope(mlir::func::FuncOp func,
+                                                   fir::DummyScopeOp scope) {
+    auto &scopeMap = scopeNames.at(func);
+    return forrest.getFuncTreeWithScope(func, scopeMap.lookup(scope));
+  }
+
+  void processFunctionScopes(mlir::func::FuncOp func);
+  fir::DummyScopeOp getDeclarationScope(fir::DeclareOp declareOp);
 
 private:
+  mlir::DominanceInfo &domInfo;
   fir::AliasAnalysis analysis;
   llvm::DenseMap<mlir::Value, fir::AliasAnalysis::Source> analysisCache;
   fir::TBAAForrest forrest;
+  // Unique names for fir.dummy_scope operations within
+  // the given function.
+  llvm::DenseMap<mlir::func::FuncOp,
+                 llvm::DenseMap<fir::DummyScopeOp, std::string>>
+      scopeNames;
+  // A map providing a vector of fir.dummy_scope operations
+  // for the given function. The vectors are sorted according
+  // to the dominance information.
+  llvm::DenseMap<mlir::func::FuncOp, llvm::SmallVector<fir::DummyScopeOp, 16>>
+      sortedScopeOperations;
 };
 
+// Process fir.dummy_scope operations in the given func:
+// sort them according to the dominance information, and
+// associate a unique (within the current function) scope name
+// with each of them.
+void PassState::processFunctionScopes(mlir::func::FuncOp func) {
+  if (scopeNames.contains(func))
+    return;
+
+  auto &scopeMap = scopeNames.getOrInsertDefault(func);
+  auto &scopeOps = sortedScopeOperations.getOrInsertDefault(func);
+  func.walk([&](fir::DummyScopeOp op) { scopeOps.push_back(op); });
+  llvm::stable_sort(scopeOps, [&](const fir::DummyScopeOp &op1,
+                                  const fir::DummyScopeOp &op2) {
+    return domInfo.properlyDominates(&*op1, &*op2);
+  });
+  unsigned scopeId = 0;
+  for (auto scope : scopeOps) {
+    if (scopeId != 0) {
+      std::string name = (llvm::Twine("Scope ") + llvm::Twine(scopeId)).str();
+      LLVM_DEBUG(llvm::dbgs() << "Creating scope '" << name << "':\n"
+                              << scope << "\n");
+      scopeMap.insert({scope, std::move(name)});
+    }
+    ++scopeId;
+  }
+}
+
+// For the given fir.declare returns the dominating fir.dummy_scope
+// operation.
+fir::DummyScopeOp PassState::getDeclarationScope(fir::DeclareOp declareOp) {
+  auto func = declareOp->getParentOfType<mlir::func::FuncOp>();
+  assert(func && "fir.declare does not have parent func.func");
----------------
vzakhari wrote:

I agree, but due to line 185 this method will be called only when there is a parent `FuncOp`.

https://github.com/llvm/llvm-project/pull/92472