MFC r309124:

Upgrade our copies of clang, llvm, lldb, compiler-rt and libc++ to 3.9.0
release, and add lld 3.9.0.  Also completely revamp the build system for
clang, llvm, lldb and their related tools.

Please note that from 3.5.0 onwards, clang, llvm and lldb require C++11
support to build; see UPDATING for more information.

Release notes for llvm, clang and lld are available here:
<http://llvm.org/releases/3.9.0/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.9.0/tools/clang/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.9.0/tools/lld/docs/ReleaseNotes.html>

Thanks to Ed Maste, Bryan Drewery, Andrew Turner, Antoine Brodin and Jan
Beich for their help.

Relnotes:	yes

MFC r309147:

Pull in r282174 from upstream llvm trunk (by Krzysztof Parzyszek):

  [PPC] Set SP after loading data from stack frame, if no red zone is
  present

  Follow-up to r280705: Make sure that the SP is only restored after
  all data is loaded from the stack frame, if there is no red zone.

  This completes the fix for
  https://llvm.org/bugs/show_bug.cgi?id=26519.

  Differential Revision: https://reviews.llvm.org/D24466

Reported by:    Mark Millard
PR:             214433

MFC r309149:

Pull in r283060 from upstream llvm trunk (by Hal Finkel):

  [PowerPC] Refactor soft-float support, and enable PPC64 soft float

  This change enables soft-float for PowerPC64, and also makes
  soft-float disable all vector instruction sets for both 32-bit and
  64-bit modes. This latter part is necessary because the PPC backend
  canonicalizes many Altivec vector types to floating-point types, and
  so soft-float breaks scalarization support for many operations. Both
  for embedded targets and for operating-system kernels desiring
  soft-float support, it seems reasonable that disabling hardware
  floating-point also disables vector instructions (embedded targets
  without hardware floating point support are unlikely to have Altivec,
  etc. and operating system kernels desiring not to use floating-point
  registers to lower syscall cost are unlikely to want to use vector
  registers either). If someone needs this to work, we'll need to
  change the fact that we promote many Altivec operations to act on
  v4f32. To make it possible to disable Altivec when soft-float is
  enabled, hardware floating-point support needs to be expressed as a
  positive feature, like the others, and not a negative feature,
  because target features cannot have dependencies on the disabling of
  some other feature. So +soft-float has now become -hard-float.

  Fixes PR26970.

Pull in r283061 from upstream clang trunk (by Hal Finkel):

  [PowerPC] Enable soft-float for PPC64, and +soft-float -> -hard-float

  Enable soft-float support on PPC64, as the backend now supports it.
  Also, the backend now uses -hard-float instead of +soft-float, so set
  the target features accordingly.

  Fixes PR26970.

Reported by:	Mark Millard
PR:		214433

MFC r309212:

Add a few missed clang 3.9.0 files to OptionalObsoleteFiles.

MFC r309262:

Fix packaging for clang, lldb and lld 3.9.0

During the upgrade of clang/llvm etc to 3.9.0 in r309124, the PACKAGE
directive in the usr.bin/clang/*.mk files got dropped accidentally.

Restore it, with a few minor changes and additions:
* Correct license in clang.ucl to NCSA
* Add PACKAGE=clang for clang and most of the "ll" tools
* Put lldb in its own package
* Put lld in its own package

Reviewed by:	gjb, jmallett
Differential Revision: https://reviews.freebsd.org/D8666

MFC r309656:

During the bootstrap phase, when building the minimal llvm library on
PowerPC, add lib/Support/Atomic.cpp.  This is needed because upstream
llvm revision r271821 disabled the use of std::call_once, which causes
some fallback functions from Atomic.cpp to be used instead.

Reported by:	Mark Millard
PR:		214902

MFC r309835:

Tentatively apply https://reviews.llvm.org/D18730 to work around gcc PR
70528 (bogus error: constructor required before non-static data member).
This should fix buildworld with the external gcc package.

Reported by:	https://jenkins.freebsd.org/job/FreeBSD_HEAD_amd64_gcc/

MFC r310194:

Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
3.9.1 release.

Please note that from 3.5.0 onwards, clang, llvm and lldb require C++11
support to build; see UPDATING for more information.

Release notes for llvm, clang and lld will be available here:
<http://releases.llvm.org/3.9.1/docs/ReleaseNotes.html>
<http://releases.llvm.org/3.9.1/tools/clang/docs/ReleaseNotes.html>
<http://releases.llvm.org/3.9.1/tools/lld/docs/ReleaseNotes.html>

Relnotes:	yes

1 files changed, 103 insertions, 18 deletions

diff --git a/contrib/llvm/lib/Bitcode/Writer/ValueEnumerator.h b/contrib/llvm/lib/Bitcode/Writer/ValueEnumerator.h
index 9fb8325..a8d6cf9 100644
--- a/contrib/llvm/lib/Bitcode/Writer/ValueEnumerator.h
+++ b/contrib/llvm/lib/Bitcode/Writer/ValueEnumerator.h
@@ -15,9 +15,10 @@
 #define LLVM_LIB_BITCODE_WRITER_VALUEENUMERATOR_H
 
 #include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/UniqueVector.h"
 #include "llvm/IR/Attributes.h"
+#include "llvm/IR/Metadata.h"
+#include "llvm/IR/Type.h"
 #include "llvm/IR/UseListOrder.h"
 #include <vector>
 
@@ -33,6 +34,7 @@ class Module;
 class Metadata;
 class LocalAsMetadata;
 class MDNode;
+class MDOperand;
 class NamedMDNode;
 class AttributeSet;
 class ValueSymbolTable;
@@ -61,12 +63,43 @@ private:
   ComdatSetType Comdats;
 
   std::vector<const Metadata *> MDs;
-  SmallVector<const LocalAsMetadata *, 8> FunctionLocalMDs;
-  typedef DenseMap<const Metadata *, unsigned> MetadataMapType;
+  std::vector<const Metadata *> FunctionMDs;
+
+  /// Index of information about a piece of metadata.
+  struct MDIndex {
+    unsigned F = 0;  ///< The ID of the function for this metadata, if any.
+    unsigned ID = 0; ///< The implicit ID of this metadata in bitcode.
+
+    MDIndex() = default;
+    explicit MDIndex(unsigned F) : F(F) {}
+
+    /// Check if this has a function tag, and it's different from NewF.
+    bool hasDifferentFunction(unsigned NewF) const { return F && F != NewF; }
+
+    /// Fetch the MD this references out of the given metadata array.
+    const Metadata *get(ArrayRef<const Metadata *> MDs) const {
+      assert(ID && "Expected non-zero ID");
+      assert(ID <= MDs.size() && "Expected valid ID");
+      return MDs[ID - 1];
+    }
+  };
+
+  typedef DenseMap<const Metadata *, MDIndex> MetadataMapType;
   MetadataMapType MetadataMap;
-  bool HasMDString;
-  bool HasDILocation;
-  bool HasGenericDINode;
+
+  /// Range of metadata IDs, as a half-open range.
+  struct MDRange {
+    unsigned First = 0;
+    unsigned Last = 0;
+
+    /// Number of strings in the prefix of the metadata range.
+    unsigned NumStrings = 0;
+
+    MDRange() {}
+    explicit MDRange(unsigned First) : First(First) {}
+  };
+  SmallDenseMap<unsigned, MDRange, 1> FunctionMDInfo;
+
   bool ShouldPreserveUseListOrder;
 
   typedef DenseMap<AttributeSet, unsigned> AttributeGroupMapType;
@@ -95,7 +128,8 @@ private:
 
   /// When a function is incorporated, this is the size of the Metadatas list
   /// before incorporation.
-  unsigned NumModuleMDs;
+  unsigned NumModuleMDs = 0;
+  unsigned NumMDStrings = 0;
 
   unsigned FirstFuncConstantID;
   unsigned FirstInstID;
@@ -117,14 +151,10 @@ public:
     return ID - 1;
   }
   unsigned getMetadataOrNullID(const Metadata *MD) const {
-    return MetadataMap.lookup(MD);
+    return MetadataMap.lookup(MD).ID;
   }
   unsigned numMDs() const { return MDs.size(); }
 
-  bool hasMDString() const { return HasMDString; }
-  bool hasDILocation() const { return HasDILocation; }
-  bool hasGenericDINode() const { return HasGenericDINode; }
-
   bool shouldPreserveUseListOrder() const { return ShouldPreserveUseListOrder; }
 
   unsigned getTypeID(Type *T) const {
@@ -158,10 +188,20 @@ public:
   }
 
   const ValueList &getValues() const { return Values; }
-  const std::vector<const Metadata *> &getMDs() const { return MDs; }
-  const SmallVectorImpl<const LocalAsMetadata *> &getFunctionLocalMDs() const {
-    return FunctionLocalMDs;
+
+  /// Check whether the current block has any metadata to emit.
+  bool hasMDs() const { return NumModuleMDs < MDs.size(); }
+
+  /// Get the MDString metadata for this block.
+  ArrayRef<const Metadata *> getMDStrings() const {
+    return makeArrayRef(MDs).slice(NumModuleMDs, NumMDStrings);
+  }
+
+  /// Get the non-MDString metadata for this block.
+  ArrayRef<const Metadata *> getNonMDStrings() const {
+    return makeArrayRef(MDs).slice(NumModuleMDs).slice(NumMDStrings);
   }
+
   const TypeList &getTypes() const { return Types; }
   const std::vector<const BasicBlock*> &getBasicBlocks() const {
     return BasicBlocks;
@@ -191,9 +231,54 @@ public:
 private:
   void OptimizeConstants(unsigned CstStart, unsigned CstEnd);
 
-  void EnumerateMDNodeOperands(const MDNode *N);
-  void EnumerateMetadata(const Metadata *MD);
-  void EnumerateFunctionLocalMetadata(const LocalAsMetadata *Local);
+  /// Reorder the reachable metadata.
+  ///
+  /// This is not just an optimization, but is mandatory for emitting MDString
+  /// correctly.
+  void organizeMetadata();
+
+  /// Drop the function tag from the transitive operands of the given node.
+  void dropFunctionFromMetadata(MetadataMapType::value_type &FirstMD);
+
+  /// Incorporate the function metadata.
+  ///
+  /// This should be called before enumerating LocalAsMetadata for the
+  /// function.
+  void incorporateFunctionMetadata(const Function &F);
+
+  /// Enumerate a single instance of metadata with the given function tag.
+  ///
+  /// If \c MD has already been enumerated, check that \c F matches its
+  /// function tag.  If not, call \a dropFunctionFromMetadata().
+  ///
+  /// Otherwise, mark \c MD as visited.  Assign it an ID, or just return it if
+  /// it's an \a MDNode.
+  const MDNode *enumerateMetadataImpl(unsigned F, const Metadata *MD);
+
+  unsigned getMetadataFunctionID(const Function *F) const;
+
+  /// Enumerate reachable metadata in (almost) post-order.
+  ///
+  /// Enumerate all the metadata reachable from MD.  We want to minimize the
+  /// cost of reading bitcode records, and so the primary consideration is that
+  /// operands of uniqued nodes are resolved before the nodes are read.  This
+  /// avoids re-uniquing them on the context and factors away RAUW support.
+  ///
+  /// This algorithm guarantees that subgraphs of uniqued nodes are in
+  /// post-order.  Distinct subgraphs reachable only from a single uniqued node
+  /// will be in post-order.
+  ///
+  /// \note The relative order of a distinct and uniqued node is irrelevant.
+  /// \a organizeMetadata() will later partition distinct nodes ahead of
+  /// uniqued ones.
+  ///{
+  void EnumerateMetadata(const Function *F, const Metadata *MD);
+  void EnumerateMetadata(unsigned F, const Metadata *MD);
+  ///}
+
+  void EnumerateFunctionLocalMetadata(const Function &F,
+                                      const LocalAsMetadata *Local);
+  void EnumerateFunctionLocalMetadata(unsigned F, const LocalAsMetadata *Local);
   void EnumerateNamedMDNode(const NamedMDNode *NMD);
   void EnumerateValue(const Value *V);
   void EnumerateType(Type *T);