1 files changed, 293 insertions, 0 deletions
diff --git a/lib/Sema/IdentifierResolver.cpp b/lib/Sema/IdentifierResolver.cpp
new file mode 100644
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--- /dev/null
+++ b/lib/Sema/IdentifierResolver.cpp
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+//===- IdentifierResolver.cpp - Lexical Scope Name lookup -------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the IdentifierResolver class, which is used for lexical
+// scoped lookup, based on declaration names.
+//
+//===----------------------------------------------------------------------===//
+
+#include "IdentifierResolver.h"
+#include "clang/Basic/LangOptions.h"
+#include <list>
+#include <vector>
+
+using namespace clang;
+
+//===----------------------------------------------------------------------===//
+// IdDeclInfoMap class
+//===----------------------------------------------------------------------===//
+
+/// IdDeclInfoMap - Associates IdDeclInfos with declaration names.
+/// Allocates 'pools' (vectors of IdDeclInfos) to avoid allocating each
+/// individual IdDeclInfo to heap.
+class IdentifierResolver::IdDeclInfoMap {
+  static const unsigned int VECTOR_SIZE = 512;
+  // Holds vectors of IdDeclInfos that serve as 'pools'.
+  // New vectors are added when the current one is full.
+  std::list< std::vector<IdDeclInfo> > IDIVecs;
+  unsigned int CurIndex;
+  
+public:
+  IdDeclInfoMap() : CurIndex(VECTOR_SIZE) {}
+
+  /// Returns the IdDeclInfo associated to the DeclarationName.
+  /// It creates a new IdDeclInfo if one was not created before for this id.
+  IdDeclInfo &operator[](DeclarationName Name);
+};
+
+
+//===----------------------------------------------------------------------===//
+// IdDeclInfo Implementation
+//===----------------------------------------------------------------------===//
+
+/// AddShadowed - Add a decl by putting it directly above the 'Shadow' decl.
+/// Later lookups will find the 'Shadow' decl first. The 'Shadow' decl must
+/// be already added to the scope chain and must be in the same context as
+/// the decl that we want to add.
+void IdentifierResolver::IdDeclInfo::AddShadowed(NamedDecl *D,
+                                                 NamedDecl *Shadow) {
+  for (DeclsTy::iterator I = Decls.end(); I != Decls.begin(); --I) {
+    if (Shadow == *(I-1)) {
+      Decls.insert(I-1, D);
+      return;
+    }
+  }
+
+  assert(0 && "Shadow wasn't in scope chain!");
+}
+
+/// RemoveDecl - Remove the decl from the scope chain.
+/// The decl must already be part of the decl chain.
+void IdentifierResolver::IdDeclInfo::RemoveDecl(NamedDecl *D) {
+  for (DeclsTy::iterator I = Decls.end(); I != Decls.begin(); --I) {
+    if (D == *(I-1)) {
+      Decls.erase(I-1);
+      return;
+    }
+  }
+
+  assert(0 && "Didn't find this decl on its identifier's chain!");
+}
+
+bool 
+IdentifierResolver::IdDeclInfo::ReplaceDecl(NamedDecl *Old, NamedDecl *New) {
+  for (DeclsTy::iterator I = Decls.end(); I != Decls.begin(); --I) {
+    if (Old == *(I-1)) {
+      *(I - 1) = New;
+      return true;
+    }
+  }
+
+  return false;
+}
+
+
+//===----------------------------------------------------------------------===//
+// IdentifierResolver Implementation
+//===----------------------------------------------------------------------===//
+
+IdentifierResolver::IdentifierResolver(const LangOptions &langOpt)
+    : LangOpt(langOpt), IdDeclInfos(new IdDeclInfoMap) {
+}
+IdentifierResolver::~IdentifierResolver() {
+  delete IdDeclInfos;
+}
+
+/// isDeclInScope - If 'Ctx' is a function/method, isDeclInScope returns true
+/// if 'D' is in Scope 'S', otherwise 'S' is ignored and isDeclInScope returns
+/// true if 'D' belongs to the given declaration context.
+bool IdentifierResolver::isDeclInScope(Decl *D, DeclContext *Ctx,
+                                       ASTContext &Context, Scope *S) const {
+  Ctx = Ctx->getLookupContext();
+
+  if (Ctx->isFunctionOrMethod()) {
+    // Ignore the scopes associated within transparent declaration contexts.
+    while (S->getEntity() && 
+           ((DeclContext *)S->getEntity())->isTransparentContext())
+      S = S->getParent();
+
+    if (S->isDeclScope(Action::DeclPtrTy::make(D)))
+      return true;
+    if (LangOpt.CPlusPlus) {
+      // C++ 3.3.2p3:
+      // The name declared in a catch exception-declaration is local to the
+      // handler and shall not be redeclared in the outermost block of the
+      // handler.
+      // C++ 3.3.2p4:
+      // Names declared in the for-init-statement, and in the condition of if,
+      // while, for, and switch statements are local to the if, while, for, or
+      // switch statement (including the controlled statement), and shall not be
+      // redeclared in a subsequent condition of that statement nor in the
+      // outermost block (or, for the if statement, any of the outermost blocks)
+      // of the controlled statement.
+      //
+      assert(S->getParent() && "No TUScope?");
+      if (S->getParent()->getFlags() & Scope::ControlScope)
+        return S->getParent()->isDeclScope(Action::DeclPtrTy::make(D));
+    }
+    return false;
+  }
+
+  return D->getDeclContext()->getLookupContext() == Ctx->getPrimaryContext();
+}
+
+/// AddDecl - Link the decl to its shadowed decl chain.
+void IdentifierResolver::AddDecl(NamedDecl *D) {
+  DeclarationName Name = D->getDeclName();
+  void *Ptr = Name.getFETokenInfo<void>();
+
+  if (!Ptr) {
+    Name.setFETokenInfo(D);
+    return;
+  }
+
+  IdDeclInfo *IDI;
+
+  if (isDeclPtr(Ptr)) {
+    Name.setFETokenInfo(NULL);
+    IDI = &(*IdDeclInfos)[Name];
+    NamedDecl *PrevD = static_cast<NamedDecl*>(Ptr);
+    IDI->AddDecl(PrevD);
+  } else
+    IDI = toIdDeclInfo(Ptr);
+
+  IDI->AddDecl(D);
+}
+
+/// AddShadowedDecl - Link the decl to its shadowed decl chain putting it
+/// after the decl that the iterator points to, thus the 'Shadow' decl will be
+/// encountered before the 'D' decl.
+void IdentifierResolver::AddShadowedDecl(NamedDecl *D, NamedDecl *Shadow) {
+  assert(D->getDeclName() == Shadow->getDeclName() && "Different ids!");
+
+  DeclarationName Name = D->getDeclName();
+  void *Ptr = Name.getFETokenInfo<void>();
+  assert(Ptr && "No decl from Ptr ?");
+
+  IdDeclInfo *IDI;
+
+  if (isDeclPtr(Ptr)) {
+    Name.setFETokenInfo(NULL);
+    IDI = &(*IdDeclInfos)[Name];
+    NamedDecl *PrevD = static_cast<NamedDecl*>(Ptr);
+    assert(PrevD == Shadow && "Invalid shadow decl ?");
+    IDI->AddDecl(D);
+    IDI->AddDecl(PrevD);
+    return;
+  }
+
+  IDI = toIdDeclInfo(Ptr);
+  IDI->AddShadowed(D, Shadow);
+}
+
+/// RemoveDecl - Unlink the decl from its shadowed decl chain.
+/// The decl must already be part of the decl chain.
+void IdentifierResolver::RemoveDecl(NamedDecl *D) {
+  assert(D && "null param passed");
+  DeclarationName Name = D->getDeclName();
+  void *Ptr = Name.getFETokenInfo<void>();
+
+  assert(Ptr && "Didn't find this decl on its identifier's chain!");
+
+  if (isDeclPtr(Ptr)) {
+    assert(D == Ptr && "Didn't find this decl on its identifier's chain!");
+    Name.setFETokenInfo(NULL);
+    return;
+  }
+  
+  return toIdDeclInfo(Ptr)->RemoveDecl(D);
+}
+
+bool IdentifierResolver::ReplaceDecl(NamedDecl *Old, NamedDecl *New) {
+  assert(Old->getDeclName() == New->getDeclName() && 
+         "Cannot replace a decl with another decl of a different name");
+  
+  DeclarationName Name = Old->getDeclName();
+  void *Ptr = Name.getFETokenInfo<void>();
+
+  if (!Ptr)
+    return false;
+
+  if (isDeclPtr(Ptr)) {
+    if (Ptr == Old) {
+      Name.setFETokenInfo(New);
+      return true;
+    }
+    return false;
+  }
+
+  return toIdDeclInfo(Ptr)->ReplaceDecl(Old, New);  
+}
+
+/// begin - Returns an iterator for decls with name 'Name'.
+IdentifierResolver::iterator
+IdentifierResolver::begin(DeclarationName Name) {
+  void *Ptr = Name.getFETokenInfo<void>();
+  if (!Ptr) return end();
+
+  if (isDeclPtr(Ptr))
+    return iterator(static_cast<NamedDecl*>(Ptr));
+
+  IdDeclInfo *IDI = toIdDeclInfo(Ptr);
+
+  IdDeclInfo::DeclsTy::iterator I = IDI->decls_end();
+  if (I != IDI->decls_begin())
+    return iterator(I-1);
+  // No decls found.
+  return end();
+}
+
+void IdentifierResolver::AddDeclToIdentifierChain(IdentifierInfo *II, 
+                                                  NamedDecl *D) {
+  void *Ptr = II->getFETokenInfo<void>();
+
+  if (!Ptr) {
+    II->setFETokenInfo(D);
+    return;
+  }
+
+  IdDeclInfo *IDI;
+
+  if (isDeclPtr(Ptr)) {
+    II->setFETokenInfo(NULL);
+    IDI = &(*IdDeclInfos)[II];
+    NamedDecl *PrevD = static_cast<NamedDecl*>(Ptr);
+    IDI->AddDecl(PrevD);
+  } else
+    IDI = toIdDeclInfo(Ptr);
+
+  IDI->AddDecl(D);
+}
+
+//===----------------------------------------------------------------------===//
+// IdDeclInfoMap Implementation
+//===----------------------------------------------------------------------===//
+
+/// Returns the IdDeclInfo associated to the DeclarationName.
+/// It creates a new IdDeclInfo if one was not created before for this id.
+IdentifierResolver::IdDeclInfo &
+IdentifierResolver::IdDeclInfoMap::operator[](DeclarationName Name) {
+  void *Ptr = Name.getFETokenInfo<void>();
+
+  if (Ptr) return *toIdDeclInfo(Ptr);
+
+  if (CurIndex == VECTOR_SIZE) {
+    // Add a IdDeclInfo vector 'pool'
+    IDIVecs.push_back(std::vector<IdDeclInfo>());
+    // Fill the vector
+    IDIVecs.back().resize(VECTOR_SIZE);
+    CurIndex = 0;
+  }
+  IdDeclInfo *IDI = &IDIVecs.back()[CurIndex];
+  Name.setFETokenInfo(reinterpret_cast<void*>(
+                              reinterpret_cast<uintptr_t>(IDI) | 0x1)
+                                                                     );
+  ++CurIndex;
+  return *IDI;
+}