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, 66 insertions, 56 deletions

diff --git a/contrib/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/contrib/llvm/lib/Analysis/BasicAliasAnalysis.cpp
index f8509dd..b2c2011 100644
--- a/contrib/llvm/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/contrib/llvm/lib/Analysis/BasicAliasAnalysis.cpp
@@ -122,7 +122,7 @@ static bool isObjectSmallerThan(const Value *V, uint64_t Size,
   //      question (in this case rewind to p), or
   //    - just give up. It is up to caller to make sure the pointer is pointing
   //      to the base address the object.
-  // 
+  //
   // We go for 2nd option for simplicity.
   if (!isIdentifiedObject(V))
     return false;
@@ -130,7 +130,7 @@ static bool isObjectSmallerThan(const Value *V, uint64_t Size,
   // This function needs to use the aligned object size because we allow
   // reads a bit past the end given sufficient alignment.
   uint64_t ObjectSize = getObjectSize(V, TD, TLI, /*RoundToAlign*/true);
-  
+
   return ObjectSize != AliasAnalysis::UnknownSize && ObjectSize < Size;
 }
 
@@ -142,6 +142,17 @@ static bool isObjectSize(const Value *V, uint64_t Size,
   return ObjectSize != AliasAnalysis::UnknownSize && ObjectSize == Size;
 }
 
+/// isIdentifiedFunctionLocal - Return true if V is umabigously identified
+/// at the function-level. Different IdentifiedFunctionLocals can't alias.
+/// Further, an IdentifiedFunctionLocal can not alias with any function
+/// arguments other than itself, which is not neccessarily true for
+/// IdentifiedObjects.
+static bool isIdentifiedFunctionLocal(const Value *V)
+{
+  return isa<AllocaInst>(V) || isNoAliasCall(V) || isNoAliasArgument(V);
+}
+
+
 //===----------------------------------------------------------------------===//
 // GetElementPtr Instruction Decomposition and Analysis
 //===----------------------------------------------------------------------===//
@@ -152,7 +163,7 @@ namespace {
     EK_SignExt,
     EK_ZeroExt
   };
-  
+
   struct VariableGEPIndex {
     const Value *V;
     ExtensionKind Extension;
@@ -189,7 +200,7 @@ static Value *GetLinearExpression(Value *V, APInt &Scale, APInt &Offset,
     Offset = 0;
     return V;
   }
-  
+
   if (BinaryOperator *BOp = dyn_cast<BinaryOperator>(V)) {
     if (ConstantInt *RHSC = dyn_cast<ConstantInt>(BOp->getOperand(1))) {
       switch (BOp->getOpcode()) {
@@ -220,7 +231,7 @@ static Value *GetLinearExpression(Value *V, APInt &Scale, APInt &Offset,
       }
     }
   }
-  
+
   // Since GEP indices are sign extended anyway, we don't care about the high
   // bits of a sign or zero extended value - just scales and offsets.  The
   // extensions have to be consistent though.
@@ -237,10 +248,10 @@ static Value *GetLinearExpression(Value *V, APInt &Scale, APInt &Offset,
                                         TD, Depth+1);
     Scale = Scale.zext(OldWidth);
     Offset = Offset.zext(OldWidth);
-    
+
     return Result;
   }
-  
+
   Scale = 1;
   Offset = 0;
   return V;
@@ -265,7 +276,7 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
                        const DataLayout *TD) {
   // Limit recursion depth to limit compile time in crazy cases.
   unsigned MaxLookup = 6;
-  
+
   BaseOffs = 0;
   do {
     // See if this is a bitcast or GEP.
@@ -280,7 +291,7 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
       }
       return V;
     }
-    
+
     if (Op->getOpcode() == Instruction::BitCast) {
       V = Op->getOperand(0);
       continue;
@@ -297,15 +308,14 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
           V = Simplified;
           continue;
         }
-    
+
       return V;
     }
-    
+
     // Don't attempt to analyze GEPs over unsized objects.
-    if (!cast<PointerType>(GEPOp->getOperand(0)->getType())
-        ->getElementType()->isSized())
+    if (!GEPOp->getOperand(0)->getType()->getPointerElementType()->isSized())
       return V;
-    
+
     // If we are lacking DataLayout information, we can't compute the offets of
     // elements computed by GEPs.  However, we can handle bitcast equivalent
     // GEPs.
@@ -315,7 +325,8 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
       V = GEPOp->getOperand(0);
       continue;
     }
-    
+
+    unsigned AS = GEPOp->getPointerAddressSpace();
     // Walk the indices of the GEP, accumulating them into BaseOff/VarIndices.
     gep_type_iterator GTI = gep_type_begin(GEPOp);
     for (User::const_op_iterator I = GEPOp->op_begin()+1,
@@ -326,38 +337,37 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
         // For a struct, add the member offset.
         unsigned FieldNo = cast<ConstantInt>(Index)->getZExtValue();
         if (FieldNo == 0) continue;
-        
+
         BaseOffs += TD->getStructLayout(STy)->getElementOffset(FieldNo);
         continue;
       }
-      
+
       // For an array/pointer, add the element offset, explicitly scaled.
       if (ConstantInt *CIdx = dyn_cast<ConstantInt>(Index)) {
         if (CIdx->isZero()) continue;
         BaseOffs += TD->getTypeAllocSize(*GTI)*CIdx->getSExtValue();
         continue;
       }
-      
+
       uint64_t Scale = TD->getTypeAllocSize(*GTI);
       ExtensionKind Extension = EK_NotExtended;
-      
+
       // If the integer type is smaller than the pointer size, it is implicitly
       // sign extended to pointer size.
-      unsigned Width = cast<IntegerType>(Index->getType())->getBitWidth();
-      if (TD->getPointerSizeInBits() > Width)
+      unsigned Width = Index->getType()->getIntegerBitWidth();
+      if (TD->getPointerSizeInBits(AS) > Width)
         Extension = EK_SignExt;
-      
+
       // Use GetLinearExpression to decompose the index into a C1*V+C2 form.
       APInt IndexScale(Width, 0), IndexOffset(Width, 0);
       Index = GetLinearExpression(Index, IndexScale, IndexOffset, Extension,
                                   *TD, 0);
-      
+
       // The GEP index scale ("Scale") scales C1*V+C2, yielding (C1*V+C2)*Scale.
       // This gives us an aggregate computation of (C1*Scale)*V + C2*Scale.
       BaseOffs += IndexOffset.getSExtValue()*Scale;
       Scale *= IndexScale.getSExtValue();
-      
-      
+
       // If we already had an occurrence of this index variable, merge this
       // scale into it.  For example, we want to handle:
       //   A[x][x] -> x*16 + x*4 -> x*20
@@ -370,25 +380,25 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
           break;
         }
       }
-      
+
       // Make sure that we have a scale that makes sense for this target's
       // pointer size.
-      if (unsigned ShiftBits = 64-TD->getPointerSizeInBits()) {
+      if (unsigned ShiftBits = 64 - TD->getPointerSizeInBits(AS)) {
         Scale <<= ShiftBits;
         Scale = (int64_t)Scale >> ShiftBits;
       }
-      
+
       if (Scale) {
         VariableGEPIndex Entry = {Index, Extension,
                                   static_cast<int64_t>(Scale)};
         VarIndices.push_back(Entry);
       }
     }
-    
+
     // Analyze the base pointer next.
     V = GEPOp->getOperand(0);
   } while (--MaxLookup);
-  
+
   // If the chain of expressions is too deep, just return early.
   return V;
 }
@@ -396,7 +406,7 @@ DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
 /// GetIndexDifference - Dest and Src are the variable indices from two
 /// decomposed GetElementPtr instructions GEP1 and GEP2 which have common base
 /// pointers.  Subtract the GEP2 indices from GEP1 to find the symbolic
-/// difference between the two pointers. 
+/// difference between the two pointers.
 static void GetIndexDifference(SmallVectorImpl<VariableGEPIndex> &Dest,
                                const SmallVectorImpl<VariableGEPIndex> &Src) {
   if (Src.empty()) return;
@@ -405,12 +415,12 @@ static void GetIndexDifference(SmallVectorImpl<VariableGEPIndex> &Dest,
     const Value *V = Src[i].V;
     ExtensionKind Extension = Src[i].Extension;
     int64_t Scale = Src[i].Scale;
-    
+
     // Find V in Dest.  This is N^2, but pointer indices almost never have more
     // than a few variable indexes.
     for (unsigned j = 0, e = Dest.size(); j != e; ++j) {
       if (Dest[j].V != V || Dest[j].Extension != Extension) continue;
-      
+
       // If we found it, subtract off Scale V's from the entry in Dest.  If it
       // goes to zero, remove the entry.
       if (Dest[j].Scale != Scale)
@@ -420,7 +430,7 @@ static void GetIndexDifference(SmallVectorImpl<VariableGEPIndex> &Dest,
       Scale = 0;
       break;
     }
-    
+
     // If we didn't consume this entry, add it to the end of the Dest list.
     if (Scale) {
       VariableGEPIndex Entry = { V, Extension, -Scale };
@@ -515,7 +525,7 @@ namespace {
         return (AliasAnalysis*)this;
       return this;
     }
-    
+
   private:
     // AliasCache - Track alias queries to guard against recursion.
     typedef std::pair<Location, Location> LocPair;
@@ -685,7 +695,7 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
          "AliasAnalysis query involving multiple functions!");
 
   const Value *Object = GetUnderlyingObject(Loc.Ptr, TD);
-  
+
   // If this is a tail call and Loc.Ptr points to a stack location, we know that
   // the tail call cannot access or modify the local stack.
   // We cannot exclude byval arguments here; these belong to the caller of
@@ -695,7 +705,7 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
     if (const CallInst *CI = dyn_cast<CallInst>(CS.getInstruction()))
       if (CI->isTailCall())
         return NoModRef;
-  
+
   // If the pointer is to a locally allocated object that does not escape,
   // then the call can not mod/ref the pointer unless the call takes the pointer
   // as an argument, and itself doesn't capture it.
@@ -711,7 +721,7 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
       if (!(*CI)->getType()->isPointerTy() ||
           (!CS.doesNotCapture(ArgNo) && !CS.isByValArgument(ArgNo)))
         continue;
-      
+
       // If this is a no-capture pointer argument, see if we can tell that it
       // is impossible to alias the pointer we're checking.  If not, we have to
       // assume that the call could touch the pointer, even though it doesn't
@@ -721,7 +731,7 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
         break;
       }
     }
-    
+
     if (!PassedAsArg)
       return NoModRef;
   }
@@ -810,7 +820,7 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
     }
 
   // We can bound the aliasing properties of memset_pattern16 just as we can
-  // for memcpy/memset.  This is particularly important because the 
+  // for memcpy/memset.  This is particularly important because the
   // LoopIdiomRecognizer likes to turn loops into calls to memset_pattern16
   // whenever possible.
   else if (TLI.has(LibFunc::memset_pattern16) &&
@@ -846,8 +856,8 @@ BasicAliasAnalysis::getModRefInfo(ImmutableCallSite CS,
   return ModRefResult(AliasAnalysis::getModRefInfo(CS, Loc) & Min);
 }
 
-static bool areVarIndicesEqual(SmallVector<VariableGEPIndex, 4> &Indices1,
-                               SmallVector<VariableGEPIndex, 4> &Indices2) {
+static bool areVarIndicesEqual(SmallVectorImpl<VariableGEPIndex> &Indices1,
+                               SmallVectorImpl<VariableGEPIndex> &Indices2) {
   unsigned Size1 = Indices1.size();
   unsigned Size2 = Indices2.size();
 
@@ -914,22 +924,22 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
         GEP1VariableIndices.clear();
       }
     }
-    
+
     // If we get a No or May, then return it immediately, no amount of analysis
     // will improve this situation.
     if (BaseAlias != MustAlias) return BaseAlias;
-    
+
     // Otherwise, we have a MustAlias.  Since the base pointers alias each other
     // exactly, see if the computed offset from the common pointer tells us
     // about the relation of the resulting pointer.
     const Value *GEP1BasePtr =
       DecomposeGEPExpression(GEP1, GEP1BaseOffset, GEP1VariableIndices, TD);
-    
+
     int64_t GEP2BaseOffset;
     SmallVector<VariableGEPIndex, 4> GEP2VariableIndices;
     const Value *GEP2BasePtr =
       DecomposeGEPExpression(GEP2, GEP2BaseOffset, GEP2VariableIndices, TD);
-    
+
     // DecomposeGEPExpression and GetUnderlyingObject should return the
     // same result except when DecomposeGEPExpression has no DataLayout.
     if (GEP1BasePtr != UnderlyingV1 || GEP2BasePtr != UnderlyingV2) {
@@ -937,12 +947,12 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
              "DecomposeGEPExpression and GetUnderlyingObject disagree!");
       return MayAlias;
     }
-    
+
     // Subtract the GEP2 pointer from the GEP1 pointer to find out their
     // symbolic difference.
     GEP1BaseOffset -= GEP2BaseOffset;
     GetIndexDifference(GEP1VariableIndices, GEP2VariableIndices);
-    
+
   } else {
     // Check to see if these two pointers are related by the getelementptr
     // instruction.  If one pointer is a GEP with a non-zero index of the other
@@ -964,7 +974,7 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
 
     const Value *GEP1BasePtr =
       DecomposeGEPExpression(GEP1, GEP1BaseOffset, GEP1VariableIndices, TD);
-    
+
     // DecomposeGEPExpression and GetUnderlyingObject should return the
     // same result except when DecomposeGEPExpression has no DataLayout.
     if (GEP1BasePtr != UnderlyingV1) {
@@ -973,7 +983,7 @@ BasicAliasAnalysis::aliasGEP(const GEPOperator *GEP1, uint64_t V1Size,
       return MayAlias;
     }
   }
-  
+
   // In the two GEP Case, if there is no difference in the offsets of the
   // computed pointers, the resultant pointers are a must alias.  This
   // hapens when we have two lexically identical GEP's (for example).
@@ -1205,17 +1215,17 @@ BasicAliasAnalysis::aliasCheck(const Value *V1, uint64_t V1Size,
         (isa<Constant>(O2) && isIdentifiedObject(O1) && !isa<Constant>(O1)))
       return NoAlias;
 
-    // Arguments can't alias with local allocations or noalias calls
-    // in the same function.
-    if (((isa<Argument>(O1) && (isa<AllocaInst>(O2) || isNoAliasCall(O2))) ||
-         (isa<Argument>(O2) && (isa<AllocaInst>(O1) || isNoAliasCall(O1)))))
+    // Function arguments can't alias with things that are known to be
+    // unambigously identified at the function level.
+    if ((isa<Argument>(O1) && isIdentifiedFunctionLocal(O2)) ||
+        (isa<Argument>(O2) && isIdentifiedFunctionLocal(O1)))
       return NoAlias;
 
     // Most objects can't alias null.
     if ((isa<ConstantPointerNull>(O2) && isKnownNonNull(O1)) ||
         (isa<ConstantPointerNull>(O1) && isKnownNonNull(O2)))
       return NoAlias;
-  
+
     // If one pointer is the result of a call/invoke or load and the other is a
     // non-escaping local object within the same function, then we know the
     // object couldn't escape to a point where the call could return it.
@@ -1237,7 +1247,7 @@ BasicAliasAnalysis::aliasCheck(const Value *V1, uint64_t V1Size,
     if ((V1Size != UnknownSize && isObjectSmallerThan(O2, V1Size, *TD, *TLI)) ||
         (V2Size != UnknownSize && isObjectSmallerThan(O1, V2Size, *TD, *TLI)))
       return NoAlias;
-  
+
   // Check the cache before climbing up use-def chains. This also terminates
   // otherwise infinitely recursive queries.
   LocPair Locs(Location(V1, V1Size, V1TBAAInfo),