Import Clang r74383.

1 files changed, 322 insertions, 0 deletions

diff --git a/lib/Frontend/ResolveLocation.cpp b/lib/Frontend/ResolveLocation.cpp
new file mode 100644
index 0000000..a5f0d1f
--- /dev/null
+++ b/lib/Frontend/ResolveLocation.cpp
@@ -0,0 +1,322 @@
+//===--- 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();
+}