[clang] [llvm] [FlowSensitive] [StatusOr] [2/N] Add minimal model (PR #162932)

[Yitzhak Mandelbaum via cfe-commits]

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@@ -0,0 +1,114 @@
+//===- UncheckedStatusOrAccessModel.h -------------------------------------===//
+//
+// 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 CLANG_ANALYSIS_FLOWSENSITIVE_MODELS_UNCHECKEDSTATUSORACCESSMODEL_H
+#define CLANG_ANALYSIS_FLOWSENSITIVE_MODELS_UNCHECKEDSTATUSORACCESSMODEL_H
+
+#include "clang/AST/Type.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "clang/Analysis/CFG.h"
+#include "clang/Analysis/FlowSensitive/CFGMatchSwitch.h"
+#include "clang/Analysis/FlowSensitive/DataflowAnalysis.h"
+#include "clang/Analysis/FlowSensitive/DataflowEnvironment.h"
+#include "clang/Analysis/FlowSensitive/MatchSwitch.h"
+#include "clang/Analysis/FlowSensitive/NoopLattice.h"
+#include "clang/Analysis/FlowSensitive/StorageLocation.h"
+#include "clang/Analysis/FlowSensitive/Value.h"
+#include "clang/Basic/SourceLocation.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringRef.h"
+
+namespace clang::dataflow::statusor_model {
+
+// The helper functions exported here are for use of downstream vendor
+// extensions of this model.
+
+// Match declaration of `absl::StatusOr<T>` and bind `T` to "T".
+clang::ast_matchers::DeclarationMatcher statusOrClass();
+// Match declaration of `absl::Status`.
+clang::ast_matchers::DeclarationMatcher statusClass();
+// Match declaration of `absl::internal_statusor::OperatorBase`.
+clang::ast_matchers::DeclarationMatcher statusOrOperatorBaseClass();
+clang::ast_matchers::TypeMatcher possiblyAliasedStatusType();
+clang::ast_matchers::TypeMatcher possiblyAliasedStatusOrType();
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ymand wrote:

since this is a public API, maybe explain these 2 (in particular, how they differ from the simple versions and maybe when to prefer one vs the other?)

https://github.com/llvm/llvm-project/pull/162932