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, 233 insertions, 0 deletions

diff --git a/contrib/llvm/tools/clang/lib/CodeGen/MicrosoftVBTables.cpp b/contrib/llvm/tools/clang/lib/CodeGen/MicrosoftVBTables.cpp
new file mode 100644
index 0000000..dabf52c
--- /dev/null
+++ b/contrib/llvm/tools/clang/lib/CodeGen/MicrosoftVBTables.cpp
@@ -0,0 +1,233 @@
+//===--- MicrosoftVBTables.cpp - Virtual Base Table Emission --------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This class generates data about MSVC virtual base tables.
+//
+//===----------------------------------------------------------------------===//
+
+#include "MicrosoftVBTables.h"
+#include "CodeGenModule.h"
+#include "CGCXXABI.h"
+
+namespace clang {
+namespace CodeGen {
+
+/// Holds intermediate data about a path to a vbptr inside a base subobject.
+struct VBTablePath {
+  VBTablePath(const VBTableInfo &VBInfo)
+    : VBInfo(VBInfo), NextBase(VBInfo.VBPtrSubobject.getBase()) { }
+
+  /// All the data needed to build a vbtable, minus the GlobalVariable whose
+  /// name we haven't computed yet.
+  VBTableInfo VBInfo;
+
+  /// Next base to use for disambiguation.  Can be null if we've already
+  /// disambiguated this path once.
+  const CXXRecordDecl *NextBase;
+
+  /// Path is not really a full path like a CXXBasePath.  It holds the subset of
+  /// records that need to be mangled into the vbtable symbol name in order to get
+  /// a unique name.
+  llvm::SmallVector<const CXXRecordDecl *, 1> Path;
+};
+
+VBTableBuilder::VBTableBuilder(CodeGenModule &CGM,
+                               const CXXRecordDecl *MostDerived)
+    : CGM(CGM), MostDerived(MostDerived),
+      DerivedLayout(CGM.getContext().getASTRecordLayout(MostDerived)) {}
+
+void VBTableBuilder::enumerateVBTables(VBTableVector &VBTables) {
+  VBTablePathVector Paths;
+  findUnambiguousPaths(MostDerived, BaseSubobject(MostDerived,
+                                                  CharUnits::Zero()), Paths);
+  for (VBTablePathVector::iterator I = Paths.begin(), E = Paths.end();
+       I != E; ++I) {
+    VBTablePath *P = *I;
+    P->VBInfo.GV = getAddrOfVBTable(P->VBInfo.ReusingBase, P->Path);
+    VBTables.push_back(P->VBInfo);
+  }
+}
+
+
+void VBTableBuilder::findUnambiguousPaths(const CXXRecordDecl *ReusingBase,
+                                          BaseSubobject CurSubobject,
+                                          VBTablePathVector &Paths) {
+  size_t PathsStart = Paths.size();
+  bool ReuseVBPtrFromBase = true;
+  const CXXRecordDecl *CurBase = CurSubobject.getBase();
+  const ASTRecordLayout &Layout = CGM.getContext().getASTRecordLayout(CurBase);
+
+  // If this base has a vbptr, then we've found a path.  These are not full
+  // paths, so we don't use CXXBasePath.
+  if (Layout.hasOwnVBPtr()) {
+    ReuseVBPtrFromBase = false;
+    VBTablePath *Info = new VBTablePath(
+      VBTableInfo(ReusingBase, CurSubobject, /*GV=*/0));
+    Paths.push_back(Info);
+  }
+
+  // Recurse onto any bases which themselves have virtual bases.
+  for (CXXRecordDecl::base_class_const_iterator I = CurBase->bases_begin(),
+       E = CurBase->bases_end(); I != E; ++I) {
+    const CXXRecordDecl *Base = I->getType()->getAsCXXRecordDecl();
+    if (!Base->getNumVBases())
+      continue;  // Bases without virtual bases have no vbptrs.
+    CharUnits NextOffset;
+    const CXXRecordDecl *NextReusingBase = Base;
+    if (I->isVirtual()) {
+      if (!VBasesSeen.insert(Base))
+        continue;  // Don't visit virtual bases twice.
+      NextOffset = DerivedLayout.getVBaseClassOffset(Base);
+    } else {
+      NextOffset = (CurSubobject.getBaseOffset() +
+                    Layout.getBaseClassOffset(Base));
+
+      // If CurBase didn't have a vbptr, then ReusingBase will reuse the vbptr
+      // from the first non-virtual base with vbases for its vbptr.
+      if (ReuseVBPtrFromBase) {
+        NextReusingBase = ReusingBase;
+        ReuseVBPtrFromBase = false;
+      }
+    }
+
+    size_t NumPaths = Paths.size();
+    findUnambiguousPaths(NextReusingBase, BaseSubobject(Base, NextOffset),
+                         Paths);
+
+    // Tag paths through this base with the base itself.  We might use it to
+    // disambiguate.
+    for (size_t I = NumPaths, E = Paths.size(); I != E; ++I)
+      Paths[I]->NextBase = Base;
+  }
+
+  bool AmbiguousPaths = rebucketPaths(Paths, PathsStart);
+  if (AmbiguousPaths)
+    rebucketPaths(Paths, PathsStart, /*SecondPass=*/true);
+
+#ifndef NDEBUG
+  // Check that the paths are in fact unique.
+  for (size_t I = PathsStart + 1, E = Paths.size(); I != E; ++I) {
+    assert(Paths[I]->Path != Paths[I - 1]->Path && "vbtable paths are not unique");
+  }
+#endif
+}
+
+static bool pathCompare(VBTablePath *LHS, VBTablePath *RHS) {
+  return LHS->Path < RHS->Path;
+}
+
+void VBTableBuilder::extendPath(VBTablePath *P, bool SecondPass) {
+  assert(P->NextBase || SecondPass);
+  if (P->NextBase) {
+    P->Path.push_back(P->NextBase);
+    P->NextBase = 0;  // Prevent the path from being extended twice.
+  }
+}
+
+bool VBTableBuilder::rebucketPaths(VBTablePathVector &Paths, size_t PathsStart,
+                                   bool SecondPass) {
+  // What we're essentially doing here is bucketing together ambiguous paths.
+  // Any bucket with more than one path in it gets extended by NextBase, which
+  // is usually the direct base of the inherited the vbptr.  This code uses a
+  // sorted vector to implement a multiset to form the buckets.  Note that the
+  // ordering is based on pointers, but it doesn't change our output order.  The
+  // current algorithm is designed to match MSVC 2012's names.
+  // TODO: Implement MSVC 2010 or earlier names to avoid extra vbtable cruft.
+  VBTablePathVector PathsSorted(&Paths[PathsStart], &Paths.back() + 1);
+  std::sort(PathsSorted.begin(), PathsSorted.end(), pathCompare);
+  bool AmbiguousPaths = false;
+  for (size_t I = 0, E = PathsSorted.size(); I != E;) {
+    // Scan forward to find the end of the bucket.
+    size_t BucketStart = I;
+    do {
+      ++I;
+    } while (I != E && PathsSorted[BucketStart]->Path == PathsSorted[I]->Path);
+
+    // If this bucket has multiple paths, extend them all.
+    if (I - BucketStart > 1) {
+      AmbiguousPaths = true;
+      for (size_t II = BucketStart; II != I; ++II)
+        extendPath(PathsSorted[II], SecondPass);
+    }
+  }
+  return AmbiguousPaths;
+}
+
+llvm::GlobalVariable *
+VBTableBuilder::getAddrOfVBTable(const CXXRecordDecl *ReusingBase,
+                                 ArrayRef<const CXXRecordDecl *> BasePath) {
+  // Caching at this layer is redundant with the caching in EnumerateVBTables().
+
+  SmallString<256> OutName;
+  llvm::raw_svector_ostream Out(OutName);
+  MicrosoftMangleContext &Mangler =
+      cast<MicrosoftMangleContext>(CGM.getCXXABI().getMangleContext());
+  Mangler.mangleCXXVBTable(MostDerived, BasePath, Out);
+  Out.flush();
+  StringRef Name = OutName.str();
+
+  llvm::ArrayType *VBTableType =
+    llvm::ArrayType::get(CGM.IntTy, 1 + ReusingBase->getNumVBases());
+
+  assert(!CGM.getModule().getNamedGlobal(Name) &&
+         "vbtable with this name already exists: mangling bug?");
+  llvm::GlobalVariable *VBTable =
+    CGM.CreateOrReplaceCXXRuntimeVariable(Name, VBTableType,
+                                          llvm::GlobalValue::ExternalLinkage);
+  VBTable->setUnnamedAddr(true);
+  return VBTable;
+}
+
+void VBTableInfo::EmitVBTableDefinition(
+    CodeGenModule &CGM, const CXXRecordDecl *RD,
+    llvm::GlobalVariable::LinkageTypes Linkage) const {
+  assert(RD->getNumVBases() && ReusingBase->getNumVBases() &&
+         "should only emit vbtables for classes with vbtables");
+
+  const ASTRecordLayout &BaseLayout =
+    CGM.getContext().getASTRecordLayout(VBPtrSubobject.getBase());
+  const ASTRecordLayout &DerivedLayout =
+    CGM.getContext().getASTRecordLayout(RD);
+
+  SmallVector<llvm::Constant *, 4> Offsets(1 + ReusingBase->getNumVBases(), 0);
+
+  // The offset from ReusingBase's vbptr to itself always leads.
+  CharUnits VBPtrOffset = BaseLayout.getVBPtrOffset();
+  Offsets[0] = llvm::ConstantInt::get(CGM.IntTy, -VBPtrOffset.getQuantity());
+
+  MicrosoftVTableContext &Context = CGM.getMicrosoftVTableContext();
+  for (CXXRecordDecl::base_class_const_iterator I = ReusingBase->vbases_begin(),
+       E = ReusingBase->vbases_end(); I != E; ++I) {
+    const CXXRecordDecl *VBase = I->getType()->getAsCXXRecordDecl();
+    CharUnits Offset = DerivedLayout.getVBaseClassOffset(VBase);
+    assert(!Offset.isNegative());
+    // Make it relative to the subobject vbptr.
+    Offset -= VBPtrSubobject.getBaseOffset() + VBPtrOffset;
+    unsigned VBIndex = Context.getVBTableIndex(ReusingBase, VBase);
+    assert(Offsets[VBIndex] == 0 && "The same vbindex seen twice?");
+    Offsets[VBIndex] = llvm::ConstantInt::get(CGM.IntTy, Offset.getQuantity());
+  }
+
+  assert(Offsets.size() ==
+         cast<llvm::ArrayType>(cast<llvm::PointerType>(GV->getType())
+                               ->getElementType())->getNumElements());
+  llvm::ArrayType *VBTableType =
+    llvm::ArrayType::get(CGM.IntTy, Offsets.size());
+  llvm::Constant *Init = llvm::ConstantArray::get(VBTableType, Offsets);
+  GV->setInitializer(Init);
+
+  // Set the correct linkage.
+  GV->setLinkage(Linkage);
+
+  // Set the right visibility.
+  CGM.setTypeVisibility(GV, RD, CodeGenModule::TVK_ForVTable);
+}
+
+} // namespace CodeGen
+} // namespace clang