MFC 261991:

Upgrade our copy of llvm/clang to 3.4 release.  This version supports
all of the features in the current working draft of the upcoming C++
standard, provisionally named C++1y.

The code generator's performance is greatly increased, and the loop
auto-vectorizer is now enabled at -Os and -O2 in addition to -O3.  The
PowerPC backend has made several major improvements to code generation
quality and compile time, and the X86, SPARC, ARM32, Aarch64 and SystemZ
backends have all seen major feature work.

Release notes for llvm and clang can be found here:
<http://llvm.org/releases/3.4/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.4/tools/clang/docs/ReleaseNotes.html>

MFC 262121 (by emaste):

Update lldb for clang/llvm 3.4 import

This commit largely restores the lldb source to the upstream r196259
snapshot with the addition of threaded inferior support and a few bug
fixes.

Specific upstream lldb revisions restored include:
   SVN      git
  181387  779e6ac
  181703  7bef4e2
  182099  b31044e
  182650  f2dcf35
  182683  0d91b80
  183862  15c1774
  183929  99447a6
  184177  0b2934b
  184948  4dc3761
  184954  007e7bc
  186990  eebd175

Sponsored by:	DARPA, AFRL

MFC 262186 (by emaste):

Fix mismerge in r262121

A break statement was lost in the merge.  The error had no functional
impact, but restore it to reduce the diff against upstream.

MFC 262303:

Pull in r197521 from upstream clang trunk (by rdivacky):

  Use the integrated assembler by default on FreeBSD/ppc and ppc64.

Requested by:	jhibbits

MFC 262611:

Pull in r196874 from upstream llvm trunk:

  Fix a crash that occurs when PWD is invalid.

  MCJIT needs to be able to run in hostile environments, even when PWD
  is invalid. There's no need to crash MCJIT in this case.

  The obvious fix is to simply leave MCContext's CompilationDir empty
  when PWD can't be determined. This way, MCJIT clients,
  and other clients that link with LLVM don't need a valid working directory.

  If we do want to guarantee valid CompilationDir, that should be done
  only for clients of getCompilationDir(). This is as simple as checking
  for an empty string.

  The only current use of getCompilationDir is EmitGenDwarfInfo, which
  won't conceivably run with an invalid working dir. However, in the
  purely hypothetically and untestable case that this happens, the
  AT_comp_dir will be omitted from the compilation_unit DIE.

This should help fix assertions occurring with ports-mgmt/tinderbox,
when it is using jails, and sometimes invalidates clang's current
working directory.

Reported by:	decke

MFC 262809:

Pull in r203007 from upstream clang trunk:

  Don't produce an alias between destructors with different calling conventions.

  Fixes pr19007.

(Please note that is an LLVM PR identifier, not a FreeBSD one.)

This should fix Firefox and/or libxul crashes (due to problems with
regparm/stdcall calling conventions) on i386.

Reported by:	multiple users on freebsd-current
PR:		bin/187103

MFC 263048:

Repair recognition of "CC" as an alias for the C++ compiler, since it
was silently broken by upstream for a Windows-specific use-case.

Apparently some versions of CMake still rely on this archaic feature...

Reported by:	rakuco

MFC 263049:

Garbage collect the old way of adding the libstdc++ include directories
in clang's InitHeaderSearch.cpp.  This has been superseded by David
Chisnall's commit in r255321.

Moreover, if libc++ is used, the libstdc++ include directories should
not be in the search path at all.  These directories are now only used
if you pass -stdlib=libstdc++.

1 files changed, 137 insertions, 58 deletions

diff --git a/contrib/llvm/tools/clang/lib/AST/DeclBase.cpp b/contrib/llvm/tools/clang/lib/AST/DeclBase.cpp
index 084a432..121c5a6 100644
--- a/contrib/llvm/tools/clang/lib/AST/DeclBase.cpp
+++ b/contrib/llvm/tools/clang/lib/AST/DeclBase.cpp
@@ -291,6 +291,16 @@ bool Decl::isUsed(bool CheckUsedAttr) const {
   return false; 
 }
 
+void Decl::markUsed(ASTContext &C) {
+  if (Used)
+    return;
+
+  if (C.getASTMutationListener())
+    C.getASTMutationListener()->DeclarationMarkedUsed(this);
+
+  Used = true;
+}
+
 bool Decl::isReferenced() const { 
   if (Referenced)
     return true;
@@ -538,6 +548,7 @@ unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
       return IDNS_Namespace;
 
     case FunctionTemplate:
+    case VarTemplate:
       return IDNS_Ordinary;
 
     case ClassTemplate:
@@ -560,6 +571,8 @@ unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
     case ClassTemplateSpecialization:
     case ClassTemplatePartialSpecialization:
     case ClassScopeFunctionSpecialization:
+    case VarTemplateSpecialization:
+    case VarTemplatePartialSpecialization:
     case ObjCImplementation:
     case ObjCCategory:
     case ObjCCategoryImpl:
@@ -595,32 +608,6 @@ const AttrVec &Decl::getAttrs() const {
   return getASTContext().getDeclAttrs(this);
 }
 
-void Decl::swapAttrs(Decl *RHS) {
-  bool HasLHSAttr = this->HasAttrs;
-  bool HasRHSAttr = RHS->HasAttrs;
-
-  // Usually, neither decl has attrs, nothing to do.
-  if (!HasLHSAttr && !HasRHSAttr) return;
-
-  // If 'this' has no attrs, swap the other way.
-  if (!HasLHSAttr)
-    return RHS->swapAttrs(this);
-
-  ASTContext &Context = getASTContext();
-
-  // Handle the case when both decls have attrs.
-  if (HasRHSAttr) {
-    std::swap(Context.getDeclAttrs(this), Context.getDeclAttrs(RHS));
-    return;
-  }
-
-  // Otherwise, LHS has an attr and RHS doesn't.
-  Context.getDeclAttrs(RHS) = Context.getDeclAttrs(this);
-  Context.eraseDeclAttrs(this);
-  this->HasAttrs = false;
-  RHS->HasAttrs = true;
-}
-
 Decl *Decl::castFromDeclContext (const DeclContext *D) {
   Decl::Kind DK = D->getDeclKind();
   switch(DK) {
@@ -819,6 +806,24 @@ bool DeclContext::isTransparentContext() const {
   return false;
 }
 
+static bool isLinkageSpecContext(const DeclContext *DC,
+                                 LinkageSpecDecl::LanguageIDs ID) {
+  while (DC->getDeclKind() != Decl::TranslationUnit) {
+    if (DC->getDeclKind() == Decl::LinkageSpec)
+      return cast<LinkageSpecDecl>(DC)->getLanguage() == ID;
+    DC = DC->getParent();
+  }
+  return false;
+}
+
+bool DeclContext::isExternCContext() const {
+  return isLinkageSpecContext(this, clang::LinkageSpecDecl::lang_c);
+}
+
+bool DeclContext::isExternCXXContext() const {
+  return isLinkageSpecContext(this, clang::LinkageSpecDecl::lang_cxx);
+}
+
 bool DeclContext::Encloses(const DeclContext *DC) const {
   if (getPrimaryContext() != this)
     return getPrimaryContext()->Encloses(DC);
@@ -939,11 +944,8 @@ void DeclContext::reconcileExternalVisibleStorage() {
   NeedToReconcileExternalVisibleStorage = false;
 
   StoredDeclsMap &Map = *LookupPtr.getPointer();
-  ExternalASTSource *Source = getParentASTContext().getExternalSource();
-  for (StoredDeclsMap::iterator I = Map.begin(); I != Map.end(); ++I) {
-    I->second.removeExternalDecls();
-    Source->FindExternalVisibleDeclsByName(this, I->first);
-  }
+  for (StoredDeclsMap::iterator I = Map.begin(); I != Map.end(); ++I)
+    I->second.setHasExternalDecls();
 }
 
 /// \brief Load the declarations within this lexical storage from an
@@ -996,8 +998,7 @@ ExternalASTSource::SetNoExternalVisibleDeclsForName(const DeclContext *DC,
   if (!(Map = DC->LookupPtr.getPointer()))
     Map = DC->CreateStoredDeclsMap(Context);
 
-  // Add an entry to the map for this name, if it's not already present.
-  (*Map)[Name];
+  (*Map)[Name].removeExternalDecls();
 
   return DeclContext::lookup_result();
 }
@@ -1012,13 +1013,38 @@ ExternalASTSource::SetExternalVisibleDeclsForName(const DeclContext *DC,
     Map = DC->CreateStoredDeclsMap(Context);
 
   StoredDeclsList &List = (*Map)[Name];
-  for (ArrayRef<NamedDecl*>::iterator
-         I = Decls.begin(), E = Decls.end(); I != E; ++I) {
-    if (List.isNull())
-      List.setOnlyValue(*I);
-    else
-      // FIXME: Need declarationReplaces handling for redeclarations in modules.
-      List.AddSubsequentDecl(*I);
+
+  // Clear out any old external visible declarations, to avoid quadratic
+  // performance in the redeclaration checks below.
+  List.removeExternalDecls();
+
+  if (!List.isNull()) {
+    // We have both existing declarations and new declarations for this name.
+    // Some of the declarations may simply replace existing ones. Handle those
+    // first.
+    llvm::SmallVector<unsigned, 8> Skip;
+    for (unsigned I = 0, N = Decls.size(); I != N; ++I)
+      if (List.HandleRedeclaration(Decls[I]))
+        Skip.push_back(I);
+    Skip.push_back(Decls.size());
+
+    // Add in any new declarations.
+    unsigned SkipPos = 0;
+    for (unsigned I = 0, N = Decls.size(); I != N; ++I) {
+      if (I == Skip[SkipPos])
+        ++SkipPos;
+      else
+        List.AddSubsequentDecl(Decls[I]);
+    }
+  } else {
+    // Convert the array to a StoredDeclsList.
+    for (ArrayRef<NamedDecl*>::iterator
+           I = Decls.begin(), E = Decls.end(); I != E; ++I) {
+      if (List.isNull())
+        List.setOnlyValue(*I);
+      else
+        List.AddSubsequentDecl(*I);
+    }
   }
 
   return List.getLookupResult();
@@ -1171,7 +1197,8 @@ StoredDeclsMap *DeclContext::buildLookup() {
   SmallVector<DeclContext *, 2> Contexts;
   collectAllContexts(Contexts);
   for (unsigned I = 0, N = Contexts.size(); I != N; ++I)
-    buildLookupImpl(Contexts[I]);
+    buildLookupImpl<&DeclContext::decls_begin,
+                    &DeclContext::decls_end>(Contexts[I]);
 
   // We no longer have any lazy decls.
   LookupPtr.setInt(false);
@@ -1183,16 +1210,26 @@ StoredDeclsMap *DeclContext::buildLookup() {
 /// declarations contained within DCtx, which will either be this
 /// DeclContext, a DeclContext linked to it, or a transparent context
 /// nested within it.
+template<DeclContext::decl_iterator (DeclContext::*Begin)() const,
+         DeclContext::decl_iterator (DeclContext::*End)() const>
 void DeclContext::buildLookupImpl(DeclContext *DCtx) {
-  for (decl_iterator I = DCtx->decls_begin(), E = DCtx->decls_end();
+  for (decl_iterator I = (DCtx->*Begin)(), E = (DCtx->*End)();
        I != E; ++I) {
     Decl *D = *I;
 
     // Insert this declaration into the lookup structure, but only if
     // it's semantically within its decl context. Any other decls which
     // should be found in this context are added eagerly.
+    //
+    // If it's from an AST file, don't add it now. It'll get handled by
+    // FindExternalVisibleDeclsByName if needed. Exception: if we're not
+    // in C++, we do not track external visible decls for the TU, so in
+    // that case we need to collect them all here.
     if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
-      if (ND->getDeclContext() == DCtx && !shouldBeHidden(ND))
+      if (ND->getDeclContext() == DCtx && !shouldBeHidden(ND) &&
+          (!ND->isFromASTFile() ||
+           (isTranslationUnit() &&
+            !getParentASTContext().getLangOpts().CPlusPlus)))
         makeDeclVisibleInContextImpl(ND, false);
 
     // If this declaration is itself a transparent declaration context
@@ -1200,7 +1237,7 @@ void DeclContext::buildLookupImpl(DeclContext *DCtx) {
     // context (recursively).
     if (DeclContext *InnerCtx = dyn_cast<DeclContext>(D))
       if (InnerCtx->isTransparentContext() || InnerCtx->isInlineNamespace())
-        buildLookupImpl(InnerCtx);
+        buildLookupImpl<Begin, End>(InnerCtx);
   }
 }
 
@@ -1223,16 +1260,14 @@ DeclContext::lookup(DeclarationName Name) {
     if (!Map)
       Map = CreateStoredDeclsMap(getParentASTContext());
 
-    // If a PCH/module has a result for this name, and we have a local
-    // declaration, we will have imported the PCH/module result when adding the
-    // local declaration or when reconciling the module.
+    // If we have a lookup result with no external decls, we are done.
     std::pair<StoredDeclsMap::iterator, bool> R =
         Map->insert(std::make_pair(Name, StoredDeclsList()));
-    if (!R.second)
+    if (!R.second && !R.first->second.hasExternalDecls())
       return R.first->second.getLookupResult();
 
     ExternalASTSource *Source = getParentASTContext().getExternalSource();
-    if (Source->FindExternalVisibleDeclsByName(this, Name)) {
+    if (Source->FindExternalVisibleDeclsByName(this, Name) || R.second) {
       if (StoredDeclsMap *Map = LookupPtr.getPointer()) {
         StoredDeclsMap::iterator I = Map->find(Name);
         if (I != Map->end())
@@ -1257,6 +1292,46 @@ DeclContext::lookup(DeclarationName Name) {
   return I->second.getLookupResult();
 }
 
+DeclContext::lookup_result
+DeclContext::noload_lookup(DeclarationName Name) {
+  assert(DeclKind != Decl::LinkageSpec &&
+         "Should not perform lookups into linkage specs!");
+  if (!hasExternalVisibleStorage())
+    return lookup(Name);
+
+  DeclContext *PrimaryContext = getPrimaryContext();
+  if (PrimaryContext != this)
+    return PrimaryContext->noload_lookup(Name);
+
+  StoredDeclsMap *Map = LookupPtr.getPointer();
+  if (LookupPtr.getInt()) {
+    // Carefully build the lookup map, without deserializing anything.
+    SmallVector<DeclContext *, 2> Contexts;
+    collectAllContexts(Contexts);
+    for (unsigned I = 0, N = Contexts.size(); I != N; ++I)
+      buildLookupImpl<&DeclContext::noload_decls_begin,
+                      &DeclContext::noload_decls_end>(Contexts[I]);
+
+    // We no longer have any lazy decls.
+    LookupPtr.setInt(false);
+
+    // There may now be names for which we have local decls but are
+    // missing the external decls. FIXME: Just set the hasExternalDecls
+    // flag on those names that have external decls.
+    NeedToReconcileExternalVisibleStorage = true;
+
+    Map = LookupPtr.getPointer();
+  }
+
+  if (!Map)
+    return lookup_result(lookup_iterator(0), lookup_iterator(0));
+
+  StoredDeclsMap::iterator I = Map->find(Name);
+  return I != Map->end()
+             ? I->second.getLookupResult()
+             : lookup_result(lookup_iterator(0), lookup_iterator(0));
+}
+
 void DeclContext::localUncachedLookup(DeclarationName Name,
                                       SmallVectorImpl<NamedDecl *> &Results) {
   Results.clear();
@@ -1338,14 +1413,7 @@ void DeclContext::makeDeclVisibleInContextWithFlags(NamedDecl *D, bool Internal,
   assert(this == getPrimaryContext() && "expected a primary DC");
 
   // Skip declarations within functions.
-  // FIXME: We shouldn't need to build lookup tables for function declarations
-  // ever, and we can't do so correctly because we can't model the nesting of
-  // scopes which occurs within functions. We use "qualified" lookup into
-  // function declarations when handling friend declarations inside nested
-  // classes, and consequently accept the following invalid code:
-  //
-  //   void f() { void g(); { int g; struct S { friend void g(); }; } }
-  if (isFunctionOrMethod() && !isa<FunctionDecl>(D))
+  if (isFunctionOrMethod())
     return;
 
   // Skip declarations which should be invisible to name lookup.
@@ -1406,7 +1474,18 @@ void DeclContext::makeDeclVisibleInContextImpl(NamedDecl *D, bool Internal) {
 
   // Insert this declaration into the map.
   StoredDeclsList &DeclNameEntries = (*Map)[D->getDeclName()];
-  if (DeclNameEntries.isNull()) {
+
+  if (Internal) {
+    // If this is being added as part of loading an external declaration,
+    // this may not be the only external declaration with this name.
+    // In this case, we never try to replace an existing declaration; we'll
+    // handle that when we finalize the list of declarations for this name.
+    DeclNameEntries.setHasExternalDecls();
+    DeclNameEntries.AddSubsequentDecl(D);
+    return;
+  }
+
+  else if (DeclNameEntries.isNull()) {
     DeclNameEntries.setOnlyValue(D);
     return;
   }