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, 111 insertions, 144 deletions

diff --git a/contrib/llvm/tools/clang/lib/CodeGen/CGCXX.cpp b/contrib/llvm/tools/clang/lib/CodeGen/CGCXX.cpp
index 983cb92..2f8a17a 100644
--- a/contrib/llvm/tools/clang/lib/CodeGen/CGCXX.cpp
+++ b/contrib/llvm/tools/clang/lib/CodeGen/CGCXX.cpp
@@ -34,6 +34,11 @@ bool CodeGenModule::TryEmitBaseDestructorAsAlias(const CXXDestructorDecl *D) {
   if (!getCodeGenOpts().CXXCtorDtorAliases)
     return true;
 
+  // Producing an alias to a base class ctor/dtor can degrade debug quality
+  // as the debugger cannot tell them appart.
+  if (getCodeGenOpts().OptimizationLevel == 0)
+    return true;
+
   // If the destructor doesn't have a trivial body, we have to emit it
   // separately.
   if (!D->hasTrivialBody())
@@ -82,60 +87,50 @@ bool CodeGenModule::TryEmitBaseDestructorAsAlias(const CXXDestructorDecl *D) {
   if (!UniqueBase)
     return true;
 
-  /// If we don't have a definition for the destructor yet, don't
-  /// emit.  We can't emit aliases to declarations; that's just not
-  /// how aliases work.
-  const CXXDestructorDecl *BaseD = UniqueBase->getDestructor();
-  if (!BaseD->isImplicit() && !BaseD->hasBody())
-    return true;
-
   // If the base is at a non-zero offset, give up.
   const ASTRecordLayout &ClassLayout = Context.getASTRecordLayout(Class);
   if (!ClassLayout.getBaseClassOffset(UniqueBase).isZero())
     return true;
 
+  // Give up if the calling conventions don't match. We could update the call,
+  // but it is probably not worth it.
+  const CXXDestructorDecl *BaseD = UniqueBase->getDestructor();
+  if (BaseD->getType()->getAs<FunctionType>()->getCallConv() !=
+      D->getType()->getAs<FunctionType>()->getCallConv())
+    return true;
+
   return TryEmitDefinitionAsAlias(GlobalDecl(D, Dtor_Base),
-                                  GlobalDecl(BaseD, Dtor_Base));
+                                  GlobalDecl(BaseD, Dtor_Base),
+                                  false);
 }
 
 /// Try to emit a definition as a global alias for another definition.
+/// If \p InEveryTU is true, we know that an equivalent alias can be produced
+/// in every translation unit.
 bool CodeGenModule::TryEmitDefinitionAsAlias(GlobalDecl AliasDecl,
-                                             GlobalDecl TargetDecl) {
+                                             GlobalDecl TargetDecl,
+                                             bool InEveryTU) {
   if (!getCodeGenOpts().CXXCtorDtorAliases)
     return true;
 
   // The alias will use the linkage of the referrent.  If we can't
   // support aliases with that linkage, fail.
-  llvm::GlobalValue::LinkageTypes Linkage
-    = getFunctionLinkage(cast<FunctionDecl>(AliasDecl.getDecl()));
-
-  switch (Linkage) {
-  // We can definitely emit aliases to definitions with external linkage.
-  case llvm::GlobalValue::ExternalLinkage:
-  case llvm::GlobalValue::ExternalWeakLinkage:
-    break;
-
-  // Same with local linkage.
-  case llvm::GlobalValue::InternalLinkage:
-  case llvm::GlobalValue::PrivateLinkage:
-  case llvm::GlobalValue::LinkerPrivateLinkage:
-    break;
-
-  // We should try to support linkonce linkages.
-  case llvm::GlobalValue::LinkOnceAnyLinkage:
-  case llvm::GlobalValue::LinkOnceODRLinkage:
-    return true;
+  llvm::GlobalValue::LinkageTypes Linkage = getFunctionLinkage(AliasDecl);
 
-  // Other linkages will probably never be supported.
-  default:
+  // We can't use an alias if the linkage is not valid for one.
+  if (!llvm::GlobalAlias::isValidLinkage(Linkage))
     return true;
-  }
 
-  llvm::GlobalValue::LinkageTypes TargetLinkage
-    = getFunctionLinkage(cast<FunctionDecl>(TargetDecl.getDecl()));
+  llvm::GlobalValue::LinkageTypes TargetLinkage =
+      getFunctionLinkage(TargetDecl);
 
-  if (llvm::GlobalValue::isWeakForLinker(TargetLinkage))
-    return true;
+  // Check if we have it already.
+  StringRef MangledName = getMangledName(AliasDecl);
+  llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
+  if (Entry && !Entry->isDeclaration())
+    return false;
+  if (Replacements.count(MangledName))
+    return false;
 
   // Derive the type for the alias.
   llvm::PointerType *AliasType
@@ -149,15 +144,41 @@ bool CodeGenModule::TryEmitDefinitionAsAlias(GlobalDecl AliasDecl,
   if (Ref->getType() != AliasType)
     Aliasee = llvm::ConstantExpr::getBitCast(Ref, AliasType);
 
+  // Instead of creating as alias to a linkonce_odr, replace all of the uses
+  // of the aliassee.
+  if (llvm::GlobalValue::isDiscardableIfUnused(Linkage) &&
+     (TargetLinkage != llvm::GlobalValue::AvailableExternallyLinkage ||
+      !TargetDecl.getDecl()->hasAttr<AlwaysInlineAttr>())) {
+    // FIXME: An extern template instanciation will create functions with
+    // linkage "AvailableExternally". In libc++, some classes also define
+    // members with attribute "AlwaysInline" and expect no reference to
+    // be generated. It is desirable to reenable this optimisation after
+    // corresponding LLVM changes.
+    Replacements[MangledName] = Aliasee;
+    return false;
+  }
+
+  if (!InEveryTU) {
+    /// If we don't have a definition for the destructor yet, don't
+    /// emit.  We can't emit aliases to declarations; that's just not
+    /// how aliases work.
+    if (Ref->isDeclaration())
+      return true;
+  }
+
+  // Don't create an alias to a linker weak symbol. This avoids producing
+  // different COMDATs in different TUs. Another option would be to
+  // output the alias both for weak_odr and linkonce_odr, but that
+  // requires explicit comdat support in the IL.
+  if (llvm::GlobalValue::isWeakForLinker(TargetLinkage))
+    return true;
+
   // Create the alias with no name.
   llvm::GlobalAlias *Alias = 
     new llvm::GlobalAlias(AliasType, Linkage, "", Aliasee, &getModule());
 
   // Switch any previous uses to the alias.
-  StringRef MangledName = getMangledName(AliasDecl);
-  llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
   if (Entry) {
-    assert(Entry->isDeclaration() && "definition already exists for alias");
     assert(Entry->getType() == AliasType &&
            "declaration exists with different type");
     Alias->takeName(Entry);
@@ -173,37 +194,26 @@ bool CodeGenModule::TryEmitDefinitionAsAlias(GlobalDecl AliasDecl,
   return false;
 }
 
-void CodeGenModule::EmitCXXConstructors(const CXXConstructorDecl *D) {
-  // The constructor used for constructing this as a complete class;
-  // constucts the virtual bases, then calls the base constructor.
-  if (!D->getParent()->isAbstract()) {
-    // We don't need to emit the complete ctor if the class is abstract.
-    EmitGlobal(GlobalDecl(D, Ctor_Complete));
-  }
-
-  // The constructor used for constructing this as a base class;
-  // ignores virtual bases.
-  if (getTarget().getCXXABI().hasConstructorVariants())
-    EmitGlobal(GlobalDecl(D, Ctor_Base));
-}
-
 void CodeGenModule::EmitCXXConstructor(const CXXConstructorDecl *ctor,
                                        CXXCtorType ctorType) {
   // The complete constructor is equivalent to the base constructor
   // for classes with no virtual bases.  Try to emit it as an alias.
   if (getTarget().getCXXABI().hasConstructorVariants() &&
-      ctorType == Ctor_Complete &&
       !ctor->getParent()->getNumVBases() &&
-      !TryEmitDefinitionAsAlias(GlobalDecl(ctor, Ctor_Complete),
-                                GlobalDecl(ctor, Ctor_Base)))
-    return;
+      (ctorType == Ctor_Complete || ctorType == Ctor_Base)) {
+    bool ProducedAlias =
+        !TryEmitDefinitionAsAlias(GlobalDecl(ctor, Ctor_Complete),
+                                  GlobalDecl(ctor, Ctor_Base), true);
+    if (ctorType == Ctor_Complete && ProducedAlias)
+      return;
+  }
 
   const CGFunctionInfo &fnInfo =
     getTypes().arrangeCXXConstructorDeclaration(ctor, ctorType);
 
   llvm::Function *fn =
     cast<llvm::Function>(GetAddrOfCXXConstructor(ctor, ctorType, &fnInfo));
-  setFunctionLinkage(ctor, fn);
+  setFunctionLinkage(GlobalDecl(ctor, ctorType), fn);
 
   CodeGenFunction(*this).GenerateCode(GlobalDecl(ctor, ctorType), fn, fnInfo);
 
@@ -229,31 +239,22 @@ CodeGenModule::GetAddrOfCXXConstructor(const CXXConstructorDecl *ctor,
                                                       /*ForVTable=*/false));
 }
 
-void CodeGenModule::EmitCXXDestructors(const CXXDestructorDecl *D) {
-  // The destructor in a virtual table is always a 'deleting'
-  // destructor, which calls the complete destructor and then uses the
-  // appropriate operator delete.
-  if (D->isVirtual())
-    EmitGlobal(GlobalDecl(D, Dtor_Deleting));
-
-  // The destructor used for destructing this as a most-derived class;
-  // call the base destructor and then destructs any virtual bases.
-  EmitGlobal(GlobalDecl(D, Dtor_Complete));
-
-  // The destructor used for destructing this as a base class; ignores
-  // virtual bases.
-  EmitGlobal(GlobalDecl(D, Dtor_Base));
-}
-
 void CodeGenModule::EmitCXXDestructor(const CXXDestructorDecl *dtor,
                                       CXXDtorType dtorType) {
   // The complete destructor is equivalent to the base destructor for
   // classes with no virtual bases, so try to emit it as an alias.
-  if (dtorType == Dtor_Complete &&
-      !dtor->getParent()->getNumVBases() &&
-      !TryEmitDefinitionAsAlias(GlobalDecl(dtor, Dtor_Complete),
-                                GlobalDecl(dtor, Dtor_Base)))
-    return;
+  if (!dtor->getParent()->getNumVBases() &&
+      (dtorType == Dtor_Complete || dtorType == Dtor_Base)) {
+    bool ProducedAlias =
+        !TryEmitDefinitionAsAlias(GlobalDecl(dtor, Dtor_Complete),
+                                  GlobalDecl(dtor, Dtor_Base), true);
+    if (ProducedAlias) {
+      if (dtorType == Dtor_Complete)
+        return;
+      if (dtor->isVirtual())
+        getVTables().EmitThunks(GlobalDecl(dtor, Dtor_Complete));
+    }
+  }
 
   // The base destructor is equivalent to the base destructor of its
   // base class if there is exactly one non-virtual base class with a
@@ -267,7 +268,7 @@ void CodeGenModule::EmitCXXDestructor(const CXXDestructorDecl *dtor,
 
   llvm::Function *fn =
     cast<llvm::Function>(GetAddrOfCXXDestructor(dtor, dtorType, &fnInfo));
-  setFunctionLinkage(dtor, fn);
+  setFunctionLinkage(GlobalDecl(dtor, dtorType), fn);
 
   CodeGenFunction(*this).GenerateCode(GlobalDecl(dtor, dtorType), fn, fnInfo);
 
@@ -278,47 +279,51 @@ void CodeGenModule::EmitCXXDestructor(const CXXDestructorDecl *dtor,
 llvm::GlobalValue *
 CodeGenModule::GetAddrOfCXXDestructor(const CXXDestructorDecl *dtor,
                                       CXXDtorType dtorType,
-                                      const CGFunctionInfo *fnInfo) {
+                                      const CGFunctionInfo *fnInfo,
+                                      llvm::FunctionType *fnType) {
   GlobalDecl GD(dtor, dtorType);
 
   StringRef name = getMangledName(GD);
   if (llvm::GlobalValue *existing = GetGlobalValue(name))
     return existing;
 
-  if (!fnInfo) fnInfo = &getTypes().arrangeCXXDestructor(dtor, dtorType);
-
-  llvm::FunctionType *fnType = getTypes().GetFunctionType(*fnInfo);
+  if (!fnType) {
+    if (!fnInfo) fnInfo = &getTypes().arrangeCXXDestructor(dtor, dtorType);
+    fnType = getTypes().GetFunctionType(*fnInfo);
+  }
   return cast<llvm::Function>(GetOrCreateLLVMFunction(name, fnType, GD,
                                                       /*ForVTable=*/false));
 }
 
-static llvm::Value *BuildVirtualCall(CodeGenFunction &CGF, uint64_t VTableIndex, 
-                                     llvm::Value *This, llvm::Type *Ty) {
+static llvm::Value *BuildAppleKextVirtualCall(CodeGenFunction &CGF,
+                                              GlobalDecl GD,
+                                              llvm::Type *Ty,
+                                              const CXXRecordDecl *RD) {
+  assert(!CGF.CGM.getTarget().getCXXABI().isMicrosoft() &&
+         "No kext in Microsoft ABI");
+  GD = GD.getCanonicalDecl();
+  CodeGenModule &CGM = CGF.CGM;
+  llvm::Value *VTable = CGM.getCXXABI().getAddrOfVTable(RD, CharUnits());
   Ty = Ty->getPointerTo()->getPointerTo();
-  
-  llvm::Value *VTable = CGF.GetVTablePtr(This, Ty);
-  llvm::Value *VFuncPtr = 
-    CGF.Builder.CreateConstInBoundsGEP1_64(VTable, VTableIndex, "vfn");
+  VTable = CGF.Builder.CreateBitCast(VTable, Ty);
+  assert(VTable && "BuildVirtualCall = kext vtbl pointer is null");
+  uint64_t VTableIndex = CGM.getItaniumVTableContext().getMethodVTableIndex(GD);
+  uint64_t AddressPoint =
+    CGM.getItaniumVTableContext().getVTableLayout(RD)
+       .getAddressPoint(BaseSubobject(RD, CharUnits::Zero()));
+  VTableIndex += AddressPoint;
+  llvm::Value *VFuncPtr =
+    CGF.Builder.CreateConstInBoundsGEP1_64(VTable, VTableIndex, "vfnkxt");
   return CGF.Builder.CreateLoad(VFuncPtr);
 }
 
-llvm::Value *
-CodeGenFunction::BuildVirtualCall(const CXXMethodDecl *MD, llvm::Value *This,
-                                  llvm::Type *Ty) {
-  MD = MD->getCanonicalDecl();
-  uint64_t VTableIndex = CGM.getVTableContext().getMethodVTableIndex(MD);
-  
-  return ::BuildVirtualCall(*this, VTableIndex, This, Ty);
-}
-
-/// BuildVirtualCall - This routine is to support gcc's kext ABI making
+/// BuildAppleKextVirtualCall - This routine is to support gcc's kext ABI making
 /// indirect call to virtual functions. It makes the call through indexing
 /// into the vtable.
 llvm::Value *
 CodeGenFunction::BuildAppleKextVirtualCall(const CXXMethodDecl *MD, 
                                   NestedNameSpecifier *Qual,
                                   llvm::Type *Ty) {
-  llvm::Value *VTable = 0;
   assert((Qual->getKind() == NestedNameSpecifier::TypeSpec) &&
          "BuildAppleKextVirtualCall - bad Qual kind");
   
@@ -330,20 +335,8 @@ CodeGenFunction::BuildAppleKextVirtualCall(const CXXMethodDecl *MD,
   
   if (const CXXDestructorDecl *DD = dyn_cast<CXXDestructorDecl>(MD))
     return BuildAppleKextVirtualDestructorCall(DD, Dtor_Complete, RD);
-  
-  VTable = CGM.getVTables().GetAddrOfVTable(RD);
-  Ty = Ty->getPointerTo()->getPointerTo();
-  VTable = Builder.CreateBitCast(VTable, Ty);
-  assert(VTable && "BuildVirtualCall = kext vtbl pointer is null");
-  MD = MD->getCanonicalDecl();
-  uint64_t VTableIndex = CGM.getVTableContext().getMethodVTableIndex(MD);
-  uint64_t AddressPoint = 
-    CGM.getVTableContext().getVTableLayout(RD)
-       .getAddressPoint(BaseSubobject(RD, CharUnits::Zero()));
-  VTableIndex += AddressPoint;
-  llvm::Value *VFuncPtr = 
-    Builder.CreateConstInBoundsGEP1_64(VTable, VTableIndex, "vfnkxt");
-  return Builder.CreateLoad(VFuncPtr);
+
+  return ::BuildAppleKextVirtualCall(*this, MD, Ty, RD);
 }
 
 /// BuildVirtualCall - This routine makes indirect vtable call for
@@ -353,42 +346,16 @@ CodeGenFunction::BuildAppleKextVirtualDestructorCall(
                                             const CXXDestructorDecl *DD,
                                             CXXDtorType Type,
                                             const CXXRecordDecl *RD) {
-  llvm::Value * Callee = 0;
   const CXXMethodDecl *MD = cast<CXXMethodDecl>(DD);
   // FIXME. Dtor_Base dtor is always direct!!
   // It need be somehow inline expanded into the caller.
   // -O does that. But need to support -O0 as well.
   if (MD->isVirtual() && Type != Dtor_Base) {
     // Compute the function type we're calling.
-    const CGFunctionInfo &FInfo = 
-      CGM.getTypes().arrangeCXXDestructor(cast<CXXDestructorDecl>(MD),
-                                          Dtor_Complete);
+    const CGFunctionInfo &FInfo =
+      CGM.getTypes().arrangeCXXDestructor(DD, Dtor_Complete);
     llvm::Type *Ty = CGM.getTypes().GetFunctionType(FInfo);
-
-    llvm::Value *VTable = CGM.getVTables().GetAddrOfVTable(RD);
-    Ty = Ty->getPointerTo()->getPointerTo();
-    VTable = Builder.CreateBitCast(VTable, Ty);
-    DD = cast<CXXDestructorDecl>(DD->getCanonicalDecl());
-    uint64_t VTableIndex = 
-      CGM.getVTableContext().getMethodVTableIndex(GlobalDecl(DD, Type));
-    uint64_t AddressPoint =
-      CGM.getVTableContext().getVTableLayout(RD)
-         .getAddressPoint(BaseSubobject(RD, CharUnits::Zero()));
-    VTableIndex += AddressPoint;
-    llvm::Value *VFuncPtr =
-      Builder.CreateConstInBoundsGEP1_64(VTable, VTableIndex, "vfnkxt");
-    Callee = Builder.CreateLoad(VFuncPtr);
+    return ::BuildAppleKextVirtualCall(*this, GlobalDecl(DD, Type), Ty, RD);
   }
-  return Callee;
+  return 0;
 }
-
-llvm::Value *
-CodeGenFunction::BuildVirtualCall(const CXXDestructorDecl *DD, CXXDtorType Type, 
-                                  llvm::Value *This, llvm::Type *Ty) {
-  DD = cast<CXXDestructorDecl>(DD->getCanonicalDecl());
-  uint64_t VTableIndex = 
-    CGM.getVTableContext().getMethodVTableIndex(GlobalDecl(DD, Type));
-
-  return ::BuildVirtualCall(*this, VTableIndex, This, Ty);
-}
-