1//===--- MacroPPCallbacks.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// This file contains implementation for the macro preprocessors callbacks.
10//
11//===----------------------------------------------------------------------===//
12
13#include "MacroPPCallbacks.h"
14#include "CGDebugInfo.h"
15#include "clang/CodeGen/ModuleBuilder.h"
16#include "clang/Lex/MacroInfo.h"
17#include "clang/Lex/Preprocessor.h"
18
19using namespace clang;
20
21void MacroPPCallbacks::writeMacroDefinition(const IdentifierInfo &II,
22 const MacroInfo &MI,
23 Preprocessor &PP, raw_ostream &Name,
24 raw_ostream &Value) {
25 Name << II.getName();
26
27 if (MI.isFunctionLike()) {
28 Name << '(';
29 if (!MI.param_empty()) {
30 MacroInfo::param_iterator AI = MI.param_begin(), E = MI.param_end();
31 for (; AI + 1 != E; ++AI) {
32 Name << (*AI)->getName();
33 Name << ',';
34 }
35
36 // Last argument.
37 if ((*AI)->getName() == "__VA_ARGS__")
38 Name << "...";
39 else
40 Name << (*AI)->getName();
41 }
42
43 if (MI.isGNUVarargs())
44 // #define foo(x...)
45 Name << "...";
46
47 Name << ')';
48 }
49
50 SmallString<128> SpellingBuffer;
51 bool First = true;
52 for (const auto &T : MI.tokens()) {
53 if (!First && T.hasLeadingSpace())
54 Value << ' ';
55
56 Value << PP.getSpelling(Tok: T, Buffer&: SpellingBuffer);
57 First = false;
58 }
59}
60
61MacroPPCallbacks::MacroPPCallbacks(CodeGenerator *Gen, Preprocessor &PP)
62 : Gen(Gen), PP(PP), Status(NoScope) {}
63
64// This is the expected flow of enter/exit compiler and user files:
65// - Main File Enter
66// - <built-in> file enter
67// {Compiler macro definitions} - (Line=0, no scope)
68// - (Optional) <command line> file enter
69// {Command line macro definitions} - (Line=0, no scope)
70// - (Optional) <command line> file exit
71// {Command line file includes} - (Line=0, Main file scope)
72// {macro definitions and file includes} - (Line!=0, Parent scope)
73// - <built-in> file exit
74// {User code macro definitions and file includes} - (Line!=0, Parent scope)
75
76llvm::DIMacroFile *MacroPPCallbacks::getCurrentScope() {
77 if (Status == MainFileScope || Status == CommandLineIncludeScope)
78 return Scopes.back();
79 return nullptr;
80}
81
82SourceLocation MacroPPCallbacks::getCorrectLocation(SourceLocation Loc) {
83 if (Status == MainFileScope || EnteredCommandLineIncludeFiles)
84 return Loc;
85
86 // While parsing skipped files, location of macros is invalid.
87 // Invalid location represents line zero.
88 return SourceLocation();
89}
90
91void MacroPPCallbacks::updateStatusToNextScope() {
92 switch (Status) {
93 case NoScope:
94 Status = InitializedScope;
95 break;
96 case InitializedScope:
97 Status = BuiltinScope;
98 break;
99 case BuiltinScope:
100 Status = CommandLineIncludeScope;
101 break;
102 case CommandLineIncludeScope:
103 Status = MainFileScope;
104 break;
105 case MainFileScope:
106 llvm_unreachable("There is no next scope, already in the final scope");
107 }
108}
109
110void MacroPPCallbacks::FileEntered(SourceLocation Loc) {
111 SourceLocation LineLoc = getCorrectLocation(Loc: LastHashLoc);
112 switch (Status) {
113 case NoScope:
114 updateStatusToNextScope();
115 break;
116 case InitializedScope:
117 updateStatusToNextScope();
118 return;
119 case BuiltinScope:
120 if (PP.getSourceManager().isWrittenInCommandLineFile(Loc))
121 return;
122 updateStatusToNextScope();
123 [[fallthrough]];
124 case CommandLineIncludeScope:
125 EnteredCommandLineIncludeFiles++;
126 break;
127 case MainFileScope:
128 break;
129 }
130
131 Scopes.push_back(Elt: Gen->getCGDebugInfo()->CreateTempMacroFile(Parent: getCurrentScope(),
132 LineLoc, FileLoc: Loc));
133}
134
135void MacroPPCallbacks::FileExited(SourceLocation Loc) {
136 switch (Status) {
137 default:
138 llvm_unreachable("Do not expect to exit a file from current scope");
139 case BuiltinScope:
140 if (!PP.getSourceManager().isWrittenInBuiltinFile(Loc))
141 // Skip next scope and change status to MainFileScope.
142 Status = MainFileScope;
143 return;
144 case CommandLineIncludeScope:
145 if (!EnteredCommandLineIncludeFiles) {
146 updateStatusToNextScope();
147 return;
148 }
149 EnteredCommandLineIncludeFiles--;
150 break;
151 case MainFileScope:
152 break;
153 }
154
155 Scopes.pop_back();
156}
157
158void MacroPPCallbacks::FileChanged(SourceLocation Loc, FileChangeReason Reason,
159 SrcMgr::CharacteristicKind FileType,
160 FileID PrevFID) {
161 // Only care about enter file or exit file changes.
162 if (Reason == EnterFile)
163 FileEntered(Loc);
164 else if (Reason == ExitFile)
165 FileExited(Loc);
166}
167
168void MacroPPCallbacks::InclusionDirective(
169 SourceLocation HashLoc, const Token &IncludeTok, StringRef FileName,
170 bool IsAngled, CharSourceRange FilenameRange, OptionalFileEntryRef File,
171 StringRef SearchPath, StringRef RelativePath, const Module *SuggestedModule,
172 bool ModuleImported, SrcMgr::CharacteristicKind FileType) {
173
174 // Record the line location of the current included file.
175 LastHashLoc = HashLoc;
176}
177
178void MacroPPCallbacks::MacroDefined(const Token &MacroNameTok,
179 const MacroDirective *MD) {
180 IdentifierInfo *Id = MacroNameTok.getIdentifierInfo();
181 SourceLocation location = getCorrectLocation(Loc: MacroNameTok.getLocation());
182 std::string NameBuffer, ValueBuffer;
183 llvm::raw_string_ostream Name(NameBuffer);
184 llvm::raw_string_ostream Value(ValueBuffer);
185 writeMacroDefinition(II: *Id, MI: *MD->getMacroInfo(), PP, Name, Value);
186 Gen->getCGDebugInfo()->CreateMacro(Parent: getCurrentScope(),
187 MType: llvm::dwarf::DW_MACINFO_define, LineLoc: location,
188 Name: Name.str(), Value: Value.str());
189}
190
191void MacroPPCallbacks::MacroUndefined(const Token &MacroNameTok,
192 const MacroDefinition &MD,
193 const MacroDirective *Undef) {
194 IdentifierInfo *Id = MacroNameTok.getIdentifierInfo();
195 SourceLocation location = getCorrectLocation(Loc: MacroNameTok.getLocation());
196 Gen->getCGDebugInfo()->CreateMacro(Parent: getCurrentScope(),
197 MType: llvm::dwarf::DW_MACINFO_undef, LineLoc: location,
198 Name: Id->getName(), Value: "");
199}
200