1 //===-- DataCollection.cpp --------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "clang/AST/DataCollection.h"
11 
12 #include "clang/Lex/Lexer.h"
13 
14 namespace clang {
15 namespace data_collection {
16 
17 /// Prints the macro name that contains the given SourceLocation into the given
18 /// raw_string_ostream.
19 static void printMacroName(llvm::raw_string_ostream &MacroStack,
20                            ASTContext &Context, SourceLocation Loc) {
21   MacroStack << Lexer::getImmediateMacroName(Loc, Context.getSourceManager(),
22                                              Context.getLangOpts());
23 
24   // Add an empty space at the end as a padding to prevent
25   // that macro names concatenate to the names of other macros.
26   MacroStack << " ";
27 }
28 
29 /// Returns a string that represents all macro expansions that expanded into the
30 /// given SourceLocation.
31 ///
32 /// If 'getMacroStack(A) == getMacroStack(B)' is true, then the SourceLocations
33 /// A and B are expanded from the same macros in the same order.
34 std::string getMacroStack(SourceLocation Loc, ASTContext &Context) {
35   std::string MacroStack;
36   llvm::raw_string_ostream MacroStackStream(MacroStack);
37   SourceManager &SM = Context.getSourceManager();
38 
39   // Iterate over all macros that expanded into the given SourceLocation.
40   while (Loc.isMacroID()) {
41     // Add the macro name to the stream.
42     printMacroName(MacroStackStream, Context, Loc);
43     Loc = SM.getImmediateMacroCallerLoc(Loc);
44   }
45   MacroStackStream.flush();
46   return MacroStack;
47 }
48 
49 } // end namespace data_collection
50 } // end namespace clang
51