[clang] [clang][ssaf] Implement TUSummaryBuilder with test infrastructure (PR #181220)

[Aviral Goel via cfe-commits]

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@@ -9,10 +9,36 @@
 #ifndef LLVM_CLANG_ANALYSIS_SCALABLE_TUSUMMARY_TUSUMMARYBUILDER_H
 #define LLVM_CLANG_ANALYSIS_SCALABLE_TUSUMMARY_TUSUMMARYBUILDER_H
 
+#include <memory>
+#include <utility>
+
 namespace clang::ssaf {
 
+class EntityId;
+class EntityName;
+class EntitySummary;
+class TUSummary;
+
 class TUSummaryBuilder {
-  // Empty for now.
+public:
+  explicit TUSummaryBuilder(TUSummary &Summary) : Summary(Summary) {}
+
+  /// Add an entity to the summary and return its EntityId.
+  /// If the entity already exists, returns the existing ID (idempotent).
+  EntityId addEntity(const EntityName &E);
+
+  /// Associate a \p Data EntitySummary with the \p Entity.
+  /// This consumes the \p Data only if \p Entity wasn't associated yet with the
+  /// same kind of EntitySummary.
+  /// \returns a pointer to the EntitySummary and whether it inserted or not.
+  /// \note Be sure to pass exactly an expression of type
+  /// \sa std::unique_ptr<EntitySummary>, otherwise the conversion operator will
+  /// automatically consume the \p Data.
+  std::pair<EntitySummary *, bool>
+  addFact(EntityId Entity, std::unique_ptr<EntitySummary> &&Data);
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aviralg wrote:

Can we rename this to `addSummary`. We don't use `fact` anywhere else and we should avoid introducing new terminology if possible.

https://github.com/llvm/llvm-project/pull/181220