1 files changed, 94 insertions, 0 deletions
diff --git a/lib/AST/ParentMap.cpp b/lib/AST/ParentMap.cpp
new file mode 100644
index 0000000..9d87daa
--- /dev/null
+++ b/lib/AST/ParentMap.cpp
@@ -0,0 +1,94 @@
+//===--- ParentMap.cpp - Mappings from Stmts to their Parents ---*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the ParentMap class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/AST/ParentMap.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/Expr.h"
+#include "llvm/ADT/DenseMap.h"
+
+using namespace clang;
+
+typedef llvm::DenseMap<Stmt*, Stmt*> MapTy;
+
+static void BuildParentMap(MapTy& M, Stmt* S) {
+  for (Stmt::child_iterator I=S->child_begin(), E=S->child_end(); I!=E; ++I)
+    if (*I) {
+      M[*I] = S;
+      BuildParentMap(M, *I);
+    }
+}
+
+ParentMap::ParentMap(Stmt* S) : Impl(0) {
+  if (S) {
+    MapTy *M = new MapTy();
+    BuildParentMap(*M, S);
+    Impl = M;    
+  }
+}
+
+ParentMap::~ParentMap() {
+  delete (MapTy*) Impl;
+}
+
+Stmt* ParentMap::getParent(Stmt* S) const {
+  MapTy* M = (MapTy*) Impl;
+  MapTy::iterator I = M->find(S);
+  return I == M->end() ? 0 : I->second;
+}
+
+Stmt *ParentMap::getParentIgnoreParens(Stmt *S) const {
+  do { S = getParent(S); } while (S && isa<ParenExpr>(S));
+  return S;
+}
+
+bool ParentMap::isConsumedExpr(Expr* E) const {
+  Stmt *P = getParent(E);
+  Stmt *DirectChild = E;
+  
+  // Ignore parents that are parentheses or casts.
+  while (P && (isa<ParenExpr>(P) || isa<CastExpr>(P))) {
+    DirectChild = P;
+    P = getParent(P);
+  }
+  
+  if (!P)
+    return false;
+  
+  switch (P->getStmtClass()) {
+    default:
+      return isa<Expr>(P);
+    case Stmt::DeclStmtClass:
+      return true;
+    case Stmt::BinaryOperatorClass: {
+      BinaryOperator *BE = cast<BinaryOperator>(P);
+      // If it is a comma, only the right side is consumed.
+      // If it isn't a comma, both sides are consumed.
+      return BE->getOpcode()!=BinaryOperator::Comma ||DirectChild==BE->getRHS();
+    }
+    case Stmt::ForStmtClass:
+      return DirectChild == cast<ForStmt>(P)->getCond();
+    case Stmt::WhileStmtClass:
+      return DirectChild == cast<WhileStmt>(P)->getCond();      
+    case Stmt::DoStmtClass:
+      return DirectChild == cast<DoStmt>(P)->getCond();
+    case Stmt::IfStmtClass:
+      return DirectChild == cast<IfStmt>(P)->getCond();
+    case Stmt::IndirectGotoStmtClass:
+      return DirectChild == cast<IndirectGotoStmt>(P)->getTarget();
+    case Stmt::SwitchStmtClass:
+      return DirectChild == cast<SwitchStmt>(P)->getCond();
+    case Stmt::ReturnStmtClass:
+      return true;
+  }
+}
+