clang-tools-extra/include-cleaner/lib/WalkAST.cpp

   1 //===--- WalkAST.cpp - Find declaration references in the AST -------------===//
   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 #include "AnalysisInternal.h"
  10 #include "clang/AST/RecursiveASTVisitor.h"
  11
  12 namespace clang {
  13 namespace include_cleaner {
  14 namespace {
  15 using DeclCallback = llvm::function_ref<void(SourceLocation, NamedDecl &)>;
  16
  17 class ASTWalker : public RecursiveASTVisitor<ASTWalker> {
  18   DeclCallback Callback;
  19
  20   void report(SourceLocation Loc, NamedDecl *ND) {
  21     if (!ND || Loc.isInvalid())
  22       return;
  23     Callback(Loc, *cast<NamedDecl>(ND->getCanonicalDecl()));
  24   }
  25
  26 public:
  27   ASTWalker(DeclCallback Callback) : Callback(Callback) {}
  28
  29   bool VisitTagTypeLoc(TagTypeLoc TTL) {
  30     report(TTL.getNameLoc(), TTL.getDecl());
  31     return true;
  32   }
  33
  34   bool VisitDeclRefExpr(DeclRefExpr *DRE) {
  35     report(DRE->getLocation(), DRE->getFoundDecl());
  36     return true;
  37   }
  38 };
  39
  40 } // namespace
  41
  42 void walkAST(Decl &Root, DeclCallback Callback) {
  43   ASTWalker(Callback).TraverseDecl(&Root);
  44 }
  45
  46 } // namespace include_cleaner
  47 } // namespace clang