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, 73 insertions, 28 deletions

diff --git a/contrib/llvm/lib/Analysis/AliasSetTracker.cpp b/contrib/llvm/lib/Analysis/AliasSetTracker.cpp
index 3094049..d349ac5 100644
--- a/contrib/llvm/lib/Analysis/AliasSetTracker.cpp
+++ b/contrib/llvm/lib/Analysis/AliasSetTracker.cpp
@@ -208,13 +208,12 @@ void AliasSetTracker::clear() {
 }
 
 
-/// findAliasSetForPointer - Given a pointer, find the one alias set to put the
-/// instruction referring to the pointer into.  If there are multiple alias sets
-/// that may alias the pointer, merge them together and return the unified set.
-///
-AliasSet *AliasSetTracker::findAliasSetForPointer(const Value *Ptr,
-                                                  uint64_t Size,
-                                                  const AAMDNodes &AAInfo) {
+/// mergeAliasSetsForPointer - Given a pointer, merge all alias sets that may
+/// alias the pointer. Return the unified set, or nullptr if no set that aliases
+/// the pointer was found.
+AliasSet *AliasSetTracker::mergeAliasSetsForPointer(const Value *Ptr,
+                                                    uint64_t Size,
+                                                    const AAMDNodes &AAInfo) {
   AliasSet *FoundSet = nullptr;
   for (iterator I = begin(), E = end(); I != E;) {
     iterator Cur = I++;
@@ -235,15 +234,15 @@ AliasSet *AliasSetTracker::findAliasSetForPointer(const Value *Ptr,
 /// alias sets.
 bool AliasSetTracker::containsPointer(const Value *Ptr, uint64_t Size,
                                       const AAMDNodes &AAInfo) const {
-  for (const_iterator I = begin(), E = end(); I != E; ++I)
-    if (!I->Forward && I->aliasesPointer(Ptr, Size, AAInfo, AA))
+  for (const AliasSet &AS : *this)
+    if (!AS.Forward && AS.aliasesPointer(Ptr, Size, AAInfo, AA))
       return true;
   return false;
 }
 
 bool AliasSetTracker::containsUnknown(const Instruction *Inst) const {
-  for (const_iterator I = begin(), E = end(); I != E; ++I)
-    if (!I->Forward && I->aliasesUnknownInst(Inst, AA))
+  for (const AliasSet &AS : *this)
+    if (!AS.Forward && AS.aliasesUnknownInst(Inst, AA))
       return true;
   return false;
 }
@@ -274,12 +273,18 @@ AliasSet &AliasSetTracker::getAliasSetForPointer(Value *Pointer, uint64_t Size,
 
   // Check to see if the pointer is already known.
   if (Entry.hasAliasSet()) {
-    Entry.updateSizeAndAAInfo(Size, AAInfo);
+    // If the size changed, we may need to merge several alias sets.
+    // Note that we can *not* return the result of mergeAliasSetsForPointer
+    // due to a quirk of alias analysis behavior. Since alias(undef, undef)
+    // is NoAlias, mergeAliasSetsForPointer(undef, ...) will not find the
+    // the right set for undef, even if it exists.
+    if (Entry.updateSizeAndAAInfo(Size, AAInfo))
+      mergeAliasSetsForPointer(Pointer, Size, AAInfo);
     // Return the set!
     return *Entry.getAliasSet(*this)->getForwardedTarget(*this);
   }
   
-  if (AliasSet *AS = findAliasSetForPointer(Pointer, Size, AAInfo)) {
+  if (AliasSet *AS = mergeAliasSetsForPointer(Pointer, Size, AAInfo)) {
     // Add it to the alias set it aliases.
     AS->addPointer(*this, Entry, Size, AAInfo);
     return *AS;
@@ -300,7 +305,7 @@ bool AliasSetTracker::add(Value *Ptr, uint64_t Size, const AAMDNodes &AAInfo) {
 
 
 bool AliasSetTracker::add(LoadInst *LI) {
-  if (LI->getOrdering() > Monotonic) return addUnknown(LI);
+  if (isStrongerThanMonotonic(LI->getOrdering())) return addUnknown(LI);
 
   AAMDNodes AAInfo;
   LI->getAAMetadata(AAInfo);
@@ -316,7 +321,7 @@ bool AliasSetTracker::add(LoadInst *LI) {
 }
 
 bool AliasSetTracker::add(StoreInst *SI) {
-  if (SI->getOrdering() > Monotonic) return addUnknown(SI);
+  if (isStrongerThanMonotonic(SI->getOrdering())) return addUnknown(SI);
 
   AAMDNodes AAInfo;
   SI->getAAMetadata(AAInfo);
@@ -342,6 +347,24 @@ bool AliasSetTracker::add(VAArgInst *VAAI) {
   return NewPtr;
 }
 
+bool AliasSetTracker::add(MemSetInst *MSI) {
+  AAMDNodes AAInfo;
+  MSI->getAAMetadata(AAInfo);
+
+  bool NewPtr;
+  uint64_t Len;
+
+  if (ConstantInt *C = dyn_cast<ConstantInt>(MSI->getLength()))
+    Len = C->getZExtValue();
+  else
+    Len = MemoryLocation::UnknownSize;
+
+  AliasSet &AS =
+      addPointer(MSI->getRawDest(), Len, AAInfo, AliasSet::ModAccess, NewPtr);
+  if (MSI->isVolatile())
+    AS.setVolatile();
+  return NewPtr;
+}
 
 bool AliasSetTracker::addUnknown(Instruction *Inst) {
   if (isa<DbgInfoIntrinsic>(Inst)) 
@@ -368,7 +391,10 @@ bool AliasSetTracker::add(Instruction *I) {
     return add(SI);
   if (VAArgInst *VAAI = dyn_cast<VAArgInst>(I))
     return add(VAAI);
+  if (MemSetInst *MSI = dyn_cast<MemSetInst>(I))
+    return add(MSI);
   return addUnknown(I);
+  // FIXME: add support of memcpy and memmove. 
 }
 
 void AliasSetTracker::add(BasicBlock &BB) {
@@ -383,10 +409,9 @@ void AliasSetTracker::add(const AliasSetTracker &AST) {
   // Loop over all of the alias sets in AST, adding the pointers contained
   // therein into the current alias sets.  This can cause alias sets to be
   // merged together in the current AST.
-  for (const_iterator I = AST.begin(), E = AST.end(); I != E; ++I) {
-    if (I->Forward) continue;   // Ignore forwarding alias sets
-    
-    AliasSet &AS = const_cast<AliasSet&>(*I);
+  for (const AliasSet &AS : AST) {
+    if (AS.Forward)
+      continue; // Ignore forwarding alias sets
 
     // If there are any call sites in the alias set, add them to this AST.
     for (unsigned i = 0, e = AS.UnknownInsts.size(); i != e; ++i)
@@ -436,7 +461,7 @@ void AliasSetTracker::remove(AliasSet &AS) {
 
 bool
 AliasSetTracker::remove(Value *Ptr, uint64_t Size, const AAMDNodes &AAInfo) {
-  AliasSet *AS = findAliasSetForPointer(Ptr, Size, AAInfo);
+  AliasSet *AS = mergeAliasSetsForPointer(Ptr, Size, AAInfo);
   if (!AS) return false;
   remove(*AS);
   return true;
@@ -449,7 +474,7 @@ bool AliasSetTracker::remove(LoadInst *LI) {
   AAMDNodes AAInfo;
   LI->getAAMetadata(AAInfo);
 
-  AliasSet *AS = findAliasSetForPointer(LI->getOperand(0), Size, AAInfo);
+  AliasSet *AS = mergeAliasSetsForPointer(LI->getOperand(0), Size, AAInfo);
   if (!AS) return false;
   remove(*AS);
   return true;
@@ -462,7 +487,7 @@ bool AliasSetTracker::remove(StoreInst *SI) {
   AAMDNodes AAInfo;
   SI->getAAMetadata(AAInfo);
 
-  AliasSet *AS = findAliasSetForPointer(SI->getOperand(1), Size, AAInfo);
+  AliasSet *AS = mergeAliasSetsForPointer(SI->getOperand(1), Size, AAInfo);
   if (!AS) return false;
   remove(*AS);
   return true;
@@ -472,13 +497,30 @@ bool AliasSetTracker::remove(VAArgInst *VAAI) {
   AAMDNodes AAInfo;
   VAAI->getAAMetadata(AAInfo);
 
-  AliasSet *AS = findAliasSetForPointer(VAAI->getOperand(0),
-                                        MemoryLocation::UnknownSize, AAInfo);
+  AliasSet *AS = mergeAliasSetsForPointer(VAAI->getOperand(0),
+                                          MemoryLocation::UnknownSize, AAInfo);
   if (!AS) return false;
   remove(*AS);
   return true;
 }
 
+bool AliasSetTracker::remove(MemSetInst *MSI) {
+  AAMDNodes AAInfo;
+  MSI->getAAMetadata(AAInfo);
+  uint64_t Len;
+
+  if (ConstantInt *C = dyn_cast<ConstantInt>(MSI->getLength()))
+    Len = C->getZExtValue();
+  else
+    Len = MemoryLocation::UnknownSize;
+
+  AliasSet *AS = mergeAliasSetsForPointer(MSI->getRawDest(), Len, AAInfo);
+  if (!AS)
+    return false;
+  remove(*AS);
+  return true;
+}
+
 bool AliasSetTracker::removeUnknown(Instruction *I) {
   if (!I->mayReadOrWriteMemory())
     return false; // doesn't alias anything
@@ -497,7 +539,10 @@ bool AliasSetTracker::remove(Instruction *I) {
     return remove(SI);
   if (VAArgInst *VAAI = dyn_cast<VAArgInst>(I))
     return remove(VAAI);
+  if (MemSetInst *MSI = dyn_cast<MemSetInst>(I))
+    return remove(MSI);
   return removeUnknown(I);
+  // FIXME: add support of memcpy and memmove. 
 }
 
 
@@ -602,14 +647,14 @@ void AliasSet::print(raw_ostream &OS) const {
 void AliasSetTracker::print(raw_ostream &OS) const {
   OS << "Alias Set Tracker: " << AliasSets.size() << " alias sets for "
      << PointerMap.size() << " pointer values.\n";
-  for (const_iterator I = begin(), E = end(); I != E; ++I)
-    I->print(OS);
+  for (const AliasSet &AS : *this)
+    AS.print(OS);
   OS << "\n";
 }
 
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
-void AliasSet::dump() const { print(dbgs()); }
-void AliasSetTracker::dump() const { print(dbgs()); }
+LLVM_DUMP_METHOD void AliasSet::dump() const { print(dbgs()); }
+LLVM_DUMP_METHOD void AliasSetTracker::dump() const { print(dbgs()); }
 #endif
 
 //===----------------------------------------------------------------------===//