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, 58 insertions, 26 deletions

diff --git a/contrib/llvm/lib/CodeGen/SplitKit.h b/contrib/llvm/lib/CodeGen/SplitKit.h
index 69c65ff..a968494 100644
--- a/contrib/llvm/lib/CodeGen/SplitKit.h
+++ b/contrib/llvm/lib/CodeGen/SplitKit.h
@@ -18,6 +18,7 @@
 #include "LiveRangeCalc.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/IntervalMap.h"
 #include "llvm/ADT/SmallPtrSet.h"
 
@@ -37,6 +38,40 @@ class VirtRegMap;
 class VNInfo;
 class raw_ostream;
 
+/// Determines the latest safe point in a block in which we can insert a split,
+/// spill or other instruction related with CurLI.
+class LLVM_LIBRARY_VISIBILITY InsertPointAnalysis {
+private:
+  const LiveIntervals &LIS;
+
+  /// Last legal insert point in each basic block in the current function.
+  /// The first entry is the first terminator, the second entry is the
+  /// last valid point to insert a split or spill for a variable that is
+  /// live into a landing pad successor.
+  SmallVector<std::pair<SlotIndex, SlotIndex>, 8> LastInsertPoint;
+
+  SlotIndex computeLastInsertPoint(const LiveInterval &CurLI,
+                                   const MachineBasicBlock &MBB);
+
+public:
+  InsertPointAnalysis(const LiveIntervals &lis, unsigned BBNum);
+
+  /// Return the base index of the last valid insert point for \pCurLI in \pMBB.
+  SlotIndex getLastInsertPoint(const LiveInterval &CurLI,
+                               const MachineBasicBlock &MBB) {
+    unsigned Num = MBB.getNumber();
+    // Inline the common simple case.
+    if (LastInsertPoint[Num].first.isValid() &&
+        !LastInsertPoint[Num].second.isValid())
+      return LastInsertPoint[Num].first;
+    return computeLastInsertPoint(CurLI, MBB);
+  }
+
+  /// Returns the last insert point as an iterator for \pCurLI in \pMBB.
+  MachineBasicBlock::iterator getLastInsertPointIter(const LiveInterval &CurLI,
+                                                     MachineBasicBlock &MBB);
+};
+
 /// SplitAnalysis - Analyze a LiveInterval, looking for live range splitting
 /// opportunities.
 class LLVM_LIBRARY_VISIBILITY SplitAnalysis {
@@ -83,15 +118,12 @@ private:
   // Current live interval.
   const LiveInterval *CurLI;
 
+  /// Insert Point Analysis.
+  InsertPointAnalysis IPA;
+
   // Sorted slot indexes of using instructions.
   SmallVector<SlotIndex, 8> UseSlots;
 
-  /// LastSplitPoint - Last legal split point in each basic block in the current
-  /// function. The first entry is the first terminator, the second entry is the
-  /// last valid split point for a variable that is live in to a landing pad
-  /// successor.
-  SmallVector<std::pair<SlotIndex, SlotIndex>, 8> LastSplitPoint;
-
   /// UseBlocks - Blocks where CurLI has uses.
   SmallVector<BlockInfo, 8> UseBlocks;
 
@@ -108,8 +140,6 @@ private:
   /// DidRepairRange - analyze was forced to shrinkToUses().
   bool DidRepairRange;
 
-  SlotIndex computeLastSplitPoint(unsigned Num);
-
   // Sumarize statistics by counting instructions using CurLI.
   void analyzeUses();
 
@@ -136,19 +166,6 @@ public:
   /// getParent - Return the last analyzed interval.
   const LiveInterval &getParent() const { return *CurLI; }
 
-  /// getLastSplitPoint - Return the base index of the last valid split point
-  /// in the basic block numbered Num.
-  SlotIndex getLastSplitPoint(unsigned Num) {
-    // Inline the common simple case.
-    if (LastSplitPoint[Num].first.isValid() &&
-        !LastSplitPoint[Num].second.isValid())
-      return LastSplitPoint[Num].first;
-    return computeLastSplitPoint(Num);
-  }
-
-  /// getLastSplitPointIter - Returns the last split point as an iterator.
-  MachineBasicBlock::iterator getLastSplitPointIter(MachineBasicBlock*);
-
   /// isOriginalEndpoint - Return true if the original live range was killed or
   /// (re-)defined at Idx. Idx should be the 'def' slot for a normal kill/def,
   /// and 'use' for an early-clobber def.
@@ -194,6 +211,14 @@ public:
   /// @param BI           The block to be isolated.
   /// @param SingleInstrs True when single instructions should be isolated.
   bool shouldSplitSingleBlock(const BlockInfo &BI, bool SingleInstrs) const;
+
+  SlotIndex getLastSplitPoint(unsigned Num) {
+    return IPA.getLastInsertPoint(*CurLI, *MF.getBlockNumbered(Num));
+  }
+
+  MachineBasicBlock::iterator getLastSplitPointIter(MachineBasicBlock *BB) {
+    return IPA.getLastInsertPointIter(*CurLI, *BB);
+  }
 };
 
 
@@ -210,6 +235,7 @@ public:
 ///
 class LLVM_LIBRARY_VISIBILITY SplitEditor {
   SplitAnalysis &SA;
+  AliasAnalysis &AA;
   LiveIntervals &LIS;
   VirtRegMap &VRM;
   MachineRegisterInfo &MRI;
@@ -329,9 +355,14 @@ private:
   MachineBasicBlock *findShallowDominator(MachineBasicBlock *MBB,
                                           MachineBasicBlock *DefMBB);
 
-  /// hoistCopiesForSize - Hoist back-copies to the complement interval in a
-  /// way that minimizes code size. This implements the SM_Size spill mode.
-  void hoistCopiesForSize();
+  /// Find out all the backCopies dominated by others.
+  void computeRedundantBackCopies(DenseSet<unsigned> &NotToHoistSet,
+                                  SmallVectorImpl<VNInfo *> &BackCopies);
+
+  /// Hoist back-copies to the complement interval. It tries to hoist all
+  /// the back-copies to one BB if it is beneficial, or else simply remove
+  /// redundant backcopies dominated by others.
+  void hoistCopies();
 
   /// transferValues - Transfer values to the new ranges.
   /// Return true if any ranges were skipped.
@@ -350,8 +381,9 @@ private:
 public:
   /// Create a new SplitEditor for editing the LiveInterval analyzed by SA.
   /// Newly created intervals will be appended to newIntervals.
-  SplitEditor(SplitAnalysis &SA, LiveIntervals&, VirtRegMap&,
-              MachineDominatorTree&, MachineBlockFrequencyInfo &);
+  SplitEditor(SplitAnalysis &SA, AliasAnalysis &AA, LiveIntervals&,
+              VirtRegMap&, MachineDominatorTree&,
+              MachineBlockFrequencyInfo &);
 
   /// reset - Prepare for a new split.
   void reset(LiveRangeEdit&, ComplementSpillMode = SM_Partition);