1 //===-- Transfer.h ----------------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //  This file defines a transfer function that evaluates a program statement and
10 //  updates an environment accordingly.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_TRANSFER_H
15 #define LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_TRANSFER_H
16 
17 #include "clang/AST/Stmt.h"
18 #include "clang/Analysis/FlowSensitive/DataflowEnvironment.h"
19 
20 namespace clang {
21 namespace dataflow {
22 
23 /// Maps statements to the environments of basic blocks that contain them.
24 class StmtToEnvMap {
25 public:
26   virtual ~StmtToEnvMap() = default;
27 
28   /// Returns the environment of the basic block that contains `S` or nullptr if
29   /// there isn't one.
30   /// FIXME: Ensure that the result can't be null and return a const reference.
31   virtual const Environment *getEnvironment(const Stmt &S) const = 0;
32 };
33 
34 /// Evaluates `S` and updates `Env` accordingly.
35 ///
36 /// Requirements:
37 ///
38 ///  `S` must not be `ParenExpr` or `ExprWithCleanups`.
39 void transfer(const StmtToEnvMap &StmtToEnv, const Stmt &S, Environment &Env);
40 
41 } // namespace dataflow
42 } // namespace clang
43 
44 #endif // LLVM_CLANG_ANALYSIS_FLOWSENSITIVE_TRANSFER_H
45