--- /dev/null
+//===--- ResolveLocation.cpp - Source location resolver ---------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This defines the ResolveLocationInAST function, which resolves a
+// source location into a <Decl *, Stmt *> pair.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Frontend/Utils.h"
+#include "clang/AST/DeclVisitor.h"
+#include "clang/AST/StmtVisitor.h"
+#include "clang/Lex/Lexer.h"
+#include "clang/Basic/SourceManager.h"
+#include "llvm/Support/Compiler.h"
+using namespace clang;
+
+namespace {
+
+/// \brief Base for the LocResolver classes. Mostly does source range checking.
+class VISIBILITY_HIDDEN LocResolverBase {
+protected:
+ ASTContext &Ctx;
+ SourceLocation Loc;
+
+ Decl *Dcl;
+ Stmt *Stm;
+ bool PassedLoc;
+
+ /// \brief Checks whether Loc is in the source range of 'D'.
+ ///
+ /// If it is, updates Dcl. If Loc is passed the source range, it sets
+ /// PassedLoc, otherwise it does nothing.
+ void CheckRange(Decl *D);
+
+ /// \brief Checks whether Loc is in the source range of 'Node'.
+ ///
+ /// If it is, updates Stm. If Loc is passed the source range, it sets
+ /// PassedLoc, otherwise it does nothing.
+ void CheckRange(Stmt *Node);
+
+ /// \brief Updates the end source range to cover the full length of the token
+ /// positioned at the end of the source range.
+ ///
+ /// e.g.,
+ /// @code
+ /// int foo
+ /// ^ ^
+ /// @endcode
+ /// will be updated to
+ /// @code
+ /// int foo
+ /// ^ ^
+ /// @endcode
+ void FixRange(SourceRange &Range);
+
+public:
+ LocResolverBase(ASTContext &ctx, SourceLocation loc)
+ : Ctx(ctx), Loc(loc), Dcl(0), Stm(0), PassedLoc(0) {}
+
+ /// \brief We found a AST node that corresponds to the source location.
+ bool FoundIt() const { return Dcl != 0 || Stm != 0; }
+
+ /// \brief We either found a AST node or we passed the source location while
+ /// searching.
+ bool Finished() const { return FoundIt() || PassedLoc; }
+
+ Decl *getDecl() const { return Dcl; }
+ Stmt *getStmt() const { return Stm; }
+
+ std::pair<Decl *, Stmt *> getResult() const {
+ return std::make_pair(getDecl(), getStmt());
+ }
+
+ /// \brief Debugging output.
+ void print(Decl *D);
+ /// \brief Debugging output.
+ void print(Stmt *Node);
+};
+
+/// \brief Searches a statement for the AST node that corresponds to a source
+/// location.
+class VISIBILITY_HIDDEN StmtLocResolver : public LocResolverBase,
+ public StmtVisitor<StmtLocResolver> {
+public:
+ StmtLocResolver(ASTContext &ctx, SourceLocation loc)
+ : LocResolverBase(ctx, loc) {}
+
+ void VisitDeclStmt(DeclStmt *Node);
+ void VisitStmt(Stmt *Node);
+};
+
+/// \brief Searches a declaration for the AST node that corresponds to a source
+/// location.
+class VISIBILITY_HIDDEN DeclLocResolver : public LocResolverBase,
+ public DeclVisitor<DeclLocResolver> {
+public:
+ DeclLocResolver(ASTContext &ctx, SourceLocation loc)
+ : LocResolverBase(ctx, loc) {}
+
+ void VisitDeclContext(DeclContext *DC);
+ void VisitTranslationUnitDecl(TranslationUnitDecl *TU);
+ void VisitVarDecl(VarDecl *D);
+ void VisitFunctionDecl(FunctionDecl *D);
+ void VisitDecl(Decl *D);
+};
+
+} // anonymous namespace
+
+void StmtLocResolver::VisitDeclStmt(DeclStmt *Node) {
+ CheckRange(Node);
+ if (!FoundIt())
+ return;
+ assert(Stm == Node && "Result not updated ?");
+
+ // Search all declarations of this DeclStmt. If we found the one corresponding
+ // to the source location, update this StmtLocResolver's result.
+ DeclLocResolver DLR(Ctx, Loc);
+ for (DeclStmt::decl_iterator
+ I = Node->decl_begin(), E = Node->decl_end(); I != E; ++I) {
+ DLR.Visit(*I);
+ if (DLR.Finished()) {
+ if (DLR.FoundIt())
+ llvm::tie(Dcl, Stm) = DLR.getResult();
+ return;
+ }
+ }
+}
+
+void StmtLocResolver::VisitStmt(Stmt *Node) {
+ CheckRange(Node);
+ if (!FoundIt())
+ return;
+ assert(Stm == Node && "Result not updated ?");
+
+ // Search the child statements.
+ StmtLocResolver SLR(Ctx, Loc);
+ for (Stmt::child_iterator
+ I = Node->child_begin(), E = Node->child_end(); I != E; ++I) {
+ SLR.Visit(*I);
+ if (!SLR.Finished())
+ continue;
+
+ // We either found it or we passed the source location.
+
+ if (SLR.FoundIt()) {
+ // Only update Dcl if we found another more immediate 'parent' Decl for
+ // the statement.
+ if (SLR.getDecl())
+ Dcl = SLR.getDecl();
+ Stm = SLR.getStmt();
+ }
+
+ return;
+ }
+}
+
+void DeclLocResolver::VisitDeclContext(DeclContext *DC) {
+ DeclLocResolver DLR(Ctx, Loc);
+ for (DeclContext::decl_iterator
+ I = DC->decls_begin(Ctx), E = DC->decls_end(Ctx); I != E; ++I) {
+ DLR.Visit(*I);
+ if (DLR.Finished()) {
+ if (DLR.FoundIt())
+ llvm::tie(Dcl, Stm) = DLR.getResult();
+ return;
+ }
+ }
+}
+
+void DeclLocResolver::VisitTranslationUnitDecl(TranslationUnitDecl *TU) {
+ VisitDeclContext(TU);
+}
+
+void DeclLocResolver::VisitFunctionDecl(FunctionDecl *D) {
+ CheckRange(D);
+ if (!FoundIt())
+ return;
+ assert(Dcl == D && "Result not updated ?");
+
+ // First, search through the parameters of the function.
+ DeclLocResolver ParmRes(Ctx, Loc);
+ for (FunctionDecl::param_iterator
+ I = D->param_begin(), E = D->param_end(); I != E; ++I) {
+ ParmRes.Visit(*I);
+ if (ParmRes.Finished()) {
+ if (ParmRes.FoundIt())
+ llvm::tie(Dcl, Stm) = ParmRes.getResult();
+ return;
+ }
+ }
+
+ // We didn't found the location in the parameters and we didn't get passed it.
+
+ // Second, search through the declarations that are part of the function.
+ // If we find he location there, we won't have to search through its body.
+ DeclLocResolver DLR(Ctx, Loc);
+ DLR.VisitDeclContext(D);
+ if (DLR.FoundIt()) {
+ llvm::tie(Dcl, Stm) = DLR.getResult();
+ return;
+ }
+
+ // We didn't find a declaration that corresponds to the source location.
+
+ // Finally, search through the body of the function.
+ if (D->isThisDeclarationADefinition()) {
+ StmtLocResolver SLR(Ctx, Loc);
+ SLR.Visit(D->getBody(Ctx));
+ if (SLR.FoundIt()) {
+ llvm::tie(Dcl, Stm) = SLR.getResult();
+ // If we didn't find a more immediate 'parent' declaration for the
+ // statement, set the function as the parent.
+ if (Dcl == 0)
+ Dcl = D;
+ }
+ }
+}
+
+void DeclLocResolver::VisitVarDecl(VarDecl *D) {
+ CheckRange(D);
+ if (!FoundIt())
+ return;
+ assert(Dcl == D && "Result not updated ?");
+
+ // Check whether the location points to the init expression.
+ if (D->getInit()) {
+ StmtLocResolver SLR(Ctx, Loc);
+ SLR.Visit(D->getInit());
+ Stm = SLR.getStmt();
+ }
+}
+
+void DeclLocResolver::VisitDecl(Decl *D) {
+ CheckRange(D);
+}
+
+void LocResolverBase::CheckRange(Decl *D) {
+ SourceRange Range = D->getSourceRange();
+ if (!Range.isValid())
+ return;
+
+ FixRange(Range);
+
+ SourceManager &SourceMgr = Ctx.getSourceManager();
+ if (SourceMgr.isBeforeInTranslationUnit(Range.getEnd(), Loc))
+ return;
+
+ if (SourceMgr.isBeforeInTranslationUnit(Loc, Range.getBegin()))
+ PassedLoc = true;
+ else
+ Dcl = D;
+}
+
+void LocResolverBase::CheckRange(Stmt *Node) {
+ SourceRange Range = Node->getSourceRange();
+ if (!Range.isValid())
+ return;
+
+ FixRange(Range);
+
+ SourceManager &SourceMgr = Ctx.getSourceManager();
+ if (SourceMgr.isBeforeInTranslationUnit(Range.getEnd(), Loc))
+ return;
+
+ if (SourceMgr.isBeforeInTranslationUnit(Loc, Range.getBegin()))
+ PassedLoc = true;
+ else
+ Stm = Node;
+}
+
+void LocResolverBase::FixRange(SourceRange &Range) {
+ if (!Range.isValid())
+ return;
+
+ unsigned TokSize = Lexer::MeasureTokenLength(Range.getEnd(),
+ Ctx.getSourceManager(),
+ Ctx.getLangOptions());
+ Range.setEnd(Range.getEnd().getFileLocWithOffset(TokSize-1));
+}
+
+void LocResolverBase::print(Decl *D) {
+ llvm::raw_ostream &OS = llvm::outs();
+ OS << "#### DECL ####\n";
+ D->print(OS, Ctx);
+ OS << " <";
+ D->getLocStart().print(OS, Ctx.getSourceManager());
+ OS << " > - <";
+ D->getLocEnd().print(OS, Ctx.getSourceManager());
+ OS << ">\n\n";
+ OS.flush();
+}
+
+void LocResolverBase::print(Stmt *Node) {
+ llvm::raw_ostream &OS = llvm::outs();
+ OS << "#### STMT ####\n";
+ Node->printPretty(OS, Ctx);
+ OS << " <";
+ Node->getLocStart().print(OS, Ctx.getSourceManager());
+ OS << " > - <";
+ Node->getLocEnd().print(OS, Ctx.getSourceManager());
+ OS << ">\n\n";
+ OS.flush();
+}
+
+
+/// \brief Returns the AST node that a source location points to.
+///
+std::pair<Decl *, Stmt *>
+clang::ResolveLocationInAST(ASTContext &Ctx, SourceLocation Loc) {
+ if (Loc.isInvalid())
+ return std::make_pair((Decl*)0, (Stmt*)0);
+
+ DeclLocResolver DLR(Ctx, Loc);
+ DLR.Visit(Ctx.getTranslationUnitDecl());
+ return DLR.getResult();
+}