Update clang, llvm, lld, lldb, compiler-rt and libc++ to 4.0.0 release:

MFC r309142 (by emaste):

Add WITH_LLD_AS_LD build knob

If set it installs LLD as /usr/bin/ld.  LLD (as of version 3.9) is not
capable of linking the world and kernel, but can self-host and link many
substantial applications. GNU ld continues to be used for the world and
kernel build, regardless of how this knob is set.

It is on by default for arm64, and off for all other CPU architectures.

Sponsored by:	The FreeBSD Foundation

MFC r310840:

Reapply 310775, now it also builds correctly if lldb is disabled:

Move llvm-objdump from CLANG_EXTRAS to installed by default

We currently install three tools from binutils 2.17.50: as, ld, and
objdump. Work is underway to migrate to a permissively-licensed
tool-chain, with one goal being the retirement of binutils 2.17.50.

LLVM's llvm-objdump is intended to be compatible with GNU objdump
although it is currently missing some options and may have formatting
differences. Enable it by default for testing and further investigation.
It may later be changed to install as /usr/bin/objdump, it becomes a
fully viable replacement.

Reviewed by:	emaste
Differential Revision:	https://reviews.freebsd.org/D8879

MFC r312855 (by emaste):

Rename LLD_AS_LD to LLD_IS_LD, for consistency with CLANG_IS_CC

Reported by:	Dan McGregor <dan.mcgregor usask.ca>

MFC r313559 | glebius | 2017-02-10 18:34:48 +0100 (Fri, 10 Feb 2017) | 5 lines

Don't check struct rtentry on FreeBSD, it is an internal kernel structure.
On other systems it may be API structure for SIOCADDRT/SIOCDELRT.

Reviewed by:	emaste, dim

MFC r314152 (by jkim):

Remove an assembler flag, which is redundant since r309124.  The upstream
took care of it by introducing a macro NO_EXEC_STACK_DIRECTIVE.

http://llvm.org/viewvc/llvm-project?rev=273500&view=rev

Reviewed by:	dim

MFC r314564:

Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
4.0.0 (branches/release_40 296509).  The release will follow soon.

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

Also note that as of 4.0.0, lld should be able to link the base system
on amd64 and aarch64.  See the WITH_LLD_IS_LLD setting in src.conf(5).
Though please be aware that this is work in progress.

Release notes for llvm, clang and lld will be available here:
<http://releases.llvm.org/4.0.0/docs/ReleaseNotes.html>
<http://releases.llvm.org/4.0.0/tools/clang/docs/ReleaseNotes.html>
<http://releases.llvm.org/4.0.0/tools/lld/docs/ReleaseNotes.html>

Thanks to Ed Maste, Jan Beich, Antoine Brodin and Eric Fiselier for
their help.

Relnotes:	yes
Exp-run:	antoine
PR:		215969, 216008

MFC r314708:

For now, revert r287232 from upstream llvm trunk (by Daniil Fukalov):

  [SCEV] limit recursion depth of CompareSCEVComplexity

  Summary:
  CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled
  loop) and runs almost infinite time.

  Added cache of "equal" SCEV pairs to earlier cutoff of further
  estimation. Recursion depth limit was also introduced as a parameter.

  Reviewers: sanjoy

  Subscribers: mzolotukhin, tstellarAMD, llvm-commits

  Differential Revision: https://reviews.llvm.org/D26389

This commit is the cause of excessive compile times on skein_block.c
(and possibly other files) during kernel builds on amd64.

We never saw the problematic behavior described in this upstream commit,
so for now it is better to revert it.  An upstream bug has been filed
here: https://bugs.llvm.org/show_bug.cgi?id=32142

Reported by:	mjg

MFC r314795:

Reapply r287232 from upstream llvm trunk (by Daniil Fukalov):

  [SCEV] limit recursion depth of CompareSCEVComplexity

  Summary:
  CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled
  loop) and runs almost infinite time.

  Added cache of "equal" SCEV pairs to earlier cutoff of further
  estimation. Recursion depth limit was also introduced as a parameter.

  Reviewers: sanjoy

  Subscribers: mzolotukhin, tstellarAMD, llvm-commits

  Differential Revision: https://reviews.llvm.org/D26389

Pull in r296992 from upstream llvm trunk (by Sanjoy Das):

  [SCEV] Decrease the recursion threshold for CompareValueComplexity

  Fixes PR32142.

  r287232 accidentally increased the recursion threshold for
  CompareValueComplexity from 2 to 32.  This change reverses that
  change by introducing a separate flag for CompareValueComplexity's
  threshold.

The latter revision fixes the excessive compile times for skein_block.c.

MFC r314907 | mmel | 2017-03-08 12:40:27 +0100 (Wed, 08 Mar 2017) | 7 lines

Unbreak ARMv6 world.

The new compiler_rt library imported with clang 4.0.0 have several fatal
issues (non-functional __udivsi3 for example) with ARM specific instrict
functions. As temporary workaround, until upstream solve these problems,
disable all thumb[1][2] related feature.

MFC r315016:

Update clang, llvm, lld, lldb, compiler-rt and libc++ to 4.0.0 release.
We were already very close to the last release candidate, so this is a
pretty minor update.

Relnotes:	yes

MFC r316005:

Revert r314907, and pull in r298713 from upstream compiler-rt trunk (by
Weiming Zhao):

  builtins: Select correct code fragments when compiling for Thumb1/Thum2/ARM ISA.

  Summary:
  Value of __ARM_ARCH_ISA_THUMB isn't based on the actual compilation
  mode (-mthumb, -marm), it reflect's capability of given CPU.

  Due to this:
   - use  __tbumb__ and __thumb2__ insteand of __ARM_ARCH_ISA_THUMB
   - use '.thumb' directive consistently  in all affected files
   - decorate all thumb functions using
     DEFINE_COMPILERRT_THUMB_FUNCTION()

  ---------
  Note: This patch doesn't fix broken Thumb1 variant of __udivsi3 !

  Reviewers: weimingz, rengolin, compnerd

  Subscribers: aemerson, dim

  Differential Revision: https://reviews.llvm.org/D30938

Discussed with:	mmel

1 files changed, 128 insertions, 0 deletions

diff --git a/contrib/llvm/lib/Target/SystemZ/SystemZHazardRecognizer.h b/contrib/llvm/lib/Target/SystemZ/SystemZHazardRecognizer.h
new file mode 100644
index 0000000..8fa54ee
--- /dev/null
+++ b/contrib/llvm/lib/Target/SystemZ/SystemZHazardRecognizer.h
@@ -0,0 +1,128 @@
+//=-- SystemZHazardRecognizer.h - SystemZ Hazard Recognizer -----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares a hazard recognizer for the SystemZ scheduler.
+//
+// This class is used by the SystemZ scheduling strategy to maintain
+// the state during scheduling, and provide cost functions for
+// scheduling candidates. This includes:
+//
+// * Decoder grouping. A decoder group can maximally hold 3 uops, and
+// instructions that always begin a new group should be scheduled when
+// the current decoder group is empty.
+// * Processor resources usage. It is beneficial to balance the use of
+// resources.
+//
+// ===---------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TARGET_SYSTEMZ_SYSTEMZHAZARDRECOGNIZER_H
+#define LLVM_LIB_TARGET_SYSTEMZ_SYSTEMZHAZARDRECOGNIZER_H
+
+#include "SystemZSubtarget.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineScheduler.h"
+#include "llvm/CodeGen/ScheduleHazardRecognizer.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/MC/MCInstrDesc.h"
+#include "llvm/Support/raw_ostream.h"
+#include <string>
+
+namespace llvm {
+
+/// SystemZHazardRecognizer maintains the state during scheduling.
+class SystemZHazardRecognizer : public ScheduleHazardRecognizer {
+
+  ScheduleDAGMI *DAG;
+  const TargetSchedModel *SchedModel;
+
+  /// Keep track of the number of decoder slots used in the current
+  /// decoder group.
+  unsigned CurrGroupSize;
+
+  /// The tracking of resources here are quite similar to the common
+  /// code use of a critical resource. However, z13 differs in the way
+  /// that it has two processor sides which may be interesting to
+  /// model in the future (a work in progress).
+
+  /// Counters for the number of uops scheduled per processor
+  /// resource.
+  SmallVector<int, 0> ProcResourceCounters;
+
+  /// This is the resource with the greatest queue, which the
+  /// scheduler tries to avoid.
+  unsigned CriticalResourceIdx;
+
+  /// Return the number of decoder slots MI requires.
+  inline unsigned getNumDecoderSlots(SUnit *SU) const;
+
+  /// Return true if MI fits into current decoder group.
+  bool fitsIntoCurrentGroup(SUnit *SU) const;
+
+  /// Two decoder groups per cycle are formed (for z13), meaning 2x3
+  /// instructions. This function returns a number between 0 and 5,
+  /// representing the current decoder slot of the current cycle.
+  unsigned getCurrCycleIdx();
+  
+  /// LastFPdOpCycleIdx stores the numbeer returned by getCurrCycleIdx()
+  /// when a stalling operation is scheduled (which uses the FPd resource).
+  unsigned LastFPdOpCycleIdx;
+
+  /// A counter of decoder groups scheduled.
+  unsigned GrpCount;
+
+  unsigned getCurrGroupSize() {return CurrGroupSize;};
+
+  /// Start next decoder group.
+  void nextGroup(bool DbgOutput = true);
+
+  /// Clear all counters for processor resources.
+  void clearProcResCounters();
+
+  /// With the goal of alternating processor sides for stalling (FPd)
+  /// ops, return true if it seems good to schedule an FPd op next.
+  bool isFPdOpPreferred_distance(const SUnit *SU);
+
+public:
+  SystemZHazardRecognizer(const MachineSchedContext *C);
+
+  void setDAG(ScheduleDAGMI *dag) {
+    DAG = dag;
+    SchedModel = dag->getSchedModel();
+  }
+  
+  HazardType getHazardType(SUnit *m, int Stalls = 0) override;    
+  void Reset() override;
+  void EmitInstruction(SUnit *SU) override;
+
+  // Cost functions used by SystemZPostRASchedStrategy while
+  // evaluating candidates.
+
+  /// Return the cost of decoder grouping for SU. If SU must start a
+  /// new decoder group, this is negative if this fits the schedule or
+  /// positive if it would mean ending a group prematurely. For normal
+  /// instructions this returns 0.
+  int groupingCost(SUnit *SU) const; 
+
+  /// Return the cost of SU in regards to processor resources usage.
+  /// A positive value means it would be better to wait with SU, while
+  /// a negative value means it would be good to schedule SU next.
+  int resourcesCost(SUnit *SU);
+
+#ifndef NDEBUG
+  // Debug dumping.
+  std::string CurGroupDbg; // current group as text
+  void dumpSU(SUnit *SU, raw_ostream &OS) const;
+  void dumpCurrGroup(std::string Msg = "") const;
+  void dumpProcResourceCounters() const;
+#endif
+};
+
+} // namespace llvm
+
+#endif /* LLVM_LIB_TARGET_SYSTEMZ_SYSTEMZHAZARDRECOGNIZER_H */