1//===- AnnotateFunctions.cpp ----------------------------------------------===//
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// Example clang plugin which adds an annotation to every function in
10// translation units that start with #pragma enable_annotate.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Frontend/FrontendPluginRegistry.h"
15#include "clang/AST/AST.h"
16#include "clang/AST/ASTConsumer.h"
17#include "clang/Lex/Preprocessor.h"
18#include "clang/Lex/LexDiagnostic.h"
19using namespace clang;
20
21namespace {
22
23static bool EnableAnnotate = false;
24static bool HandledDecl = false;
25
26class AnnotateFunctionsConsumer : public ASTConsumer {
27public:
28 bool HandleTopLevelDecl(DeclGroupRef DG) override {
29 HandledDecl = true;
30 if (!EnableAnnotate)
31 return true;
32 for (auto D : DG)
33 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
34 FD->addAttr(AnnotateAttr::CreateImplicit(FD->getASTContext(),
35 "example_annotation"));
36 return true;
37 }
38};
39
40class AnnotateFunctionsAction : public PluginASTAction {
41public:
42 std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
43 llvm::StringRef) override {
44 return llvm::make_unique<AnnotateFunctionsConsumer>();
45 }
46
47 bool ParseArgs(const CompilerInstance &CI,
48 const std::vector<std::string> &args) override {
49 return true;
50 }
51
52 PluginASTAction::ActionType getActionType() override {
53 return AddBeforeMainAction;
54 }
55};
56
57class PragmaAnnotateHandler : public PragmaHandler {
58public:
59 PragmaAnnotateHandler() : PragmaHandler("enable_annotate") { }
60
61 void HandlePragma(Preprocessor &PP, PragmaIntroducerKind Introducer,
62 Token &PragmaTok) override {
63
64 Token Tok;
65 PP.LexUnexpandedToken(Tok);
66 if (Tok.isNot(tok::eod))
67 PP.Diag(Tok, diag::ext_pp_extra_tokens_at_eol) << "pragma";
68
69 if (HandledDecl) {
70 DiagnosticsEngine &D = PP.getDiagnostics();
71 unsigned ID = D.getCustomDiagID(
72 DiagnosticsEngine::Error,
73 "#pragma enable_annotate not allowed after declarations");
74 D.Report(PragmaTok.getLocation(), ID);
75 }
76
77 EnableAnnotate = true;
78 }
79};
80
81}
82
83static FrontendPluginRegistry::Add<AnnotateFunctionsAction>
84X("annotate-fns", "annotate functions");
85
86static PragmaHandlerRegistry::Add<PragmaAnnotateHandler>
87Y("enable_annotate","enable annotation");
88