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, 56 insertions, 71 deletions

diff --git a/contrib/llvm/tools/clang/lib/CodeGen/CGAtomic.cpp b/contrib/llvm/tools/clang/lib/CodeGen/CGAtomic.cpp
index 1fc4f94..0df2a40 100644
--- a/contrib/llvm/tools/clang/lib/CodeGen/CGAtomic.cpp
+++ b/contrib/llvm/tools/clang/lib/CodeGen/CGAtomic.cpp
@@ -15,6 +15,7 @@
 #include "CGCall.h"
 #include "CodeGenModule.h"
 #include "clang/AST/ASTContext.h"
+#include "clang/CodeGen/CGFunctionInfo.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/Intrinsics.h"
@@ -93,7 +94,7 @@ namespace {
       return (ValueSizeInBits != AtomicSizeInBits);
     }
 
-    void emitMemSetZeroIfNecessary(LValue dest) const;
+    bool emitMemSetZeroIfNecessary(LValue dest) const;
 
     llvm::Value *getAtomicSizeValue() const {
       CharUnits size = CGF.getContext().toCharUnitsFromBits(AtomicSizeInBits);
@@ -106,7 +107,8 @@ namespace {
 
     /// Turn an atomic-layout object into an r-value.
     RValue convertTempToRValue(llvm::Value *addr,
-                               AggValueSlot resultSlot) const;
+                               AggValueSlot resultSlot,
+                               SourceLocation loc) const;
 
     /// Copy an atomic r-value into atomic-layout memory.
     void emitCopyIntoMemory(RValue rvalue, LValue lvalue) const;
@@ -164,21 +166,22 @@ bool AtomicInfo::requiresMemSetZero(llvm::Type *type) const {
     return !isFullSizeType(CGF.CGM, type->getStructElementType(0),
                            AtomicSizeInBits / 2);
 
-  // Just be pessimistic about aggregates.
+  // Padding in structs has an undefined bit pattern.  User beware.
   case TEK_Aggregate:
-    return true;
+    return false;
   }
   llvm_unreachable("bad evaluation kind");
 }
 
-void AtomicInfo::emitMemSetZeroIfNecessary(LValue dest) const {
+bool AtomicInfo::emitMemSetZeroIfNecessary(LValue dest) const {
   llvm::Value *addr = dest.getAddress();
   if (!requiresMemSetZero(addr->getType()->getPointerElementType()))
-    return;
+    return false;
 
   CGF.Builder.CreateMemSet(addr, llvm::ConstantInt::get(CGF.Int8Ty, 0),
                            AtomicSizeInBits / 8,
                            dest.getAlignment().getQuantity());
+  return true;
 }
 
 static void
@@ -320,11 +323,12 @@ EmitValToTemp(CodeGenFunction &CGF, Expr *E) {
 
 static void
 AddDirectArgument(CodeGenFunction &CGF, CallArgList &Args,
-                  bool UseOptimizedLibcall, llvm::Value *Val, QualType ValTy) {
+                  bool UseOptimizedLibcall, llvm::Value *Val, QualType ValTy,
+                  SourceLocation Loc) {
   if (UseOptimizedLibcall) {
     // Load value and pass it to the function directly.
     unsigned Align = CGF.getContext().getTypeAlignInChars(ValTy).getQuantity();
-    Val = CGF.EmitLoadOfScalar(Val, false, Align, ValTy);
+    Val = CGF.EmitLoadOfScalar(Val, false, Align, ValTy, Loc);
     Args.add(RValue::get(Val), ValTy);
   } else {
     // Non-optimized functions always take a reference.
@@ -469,8 +473,7 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E, llvm::Value *Dest) {
                getContext().getSizeType());
     }
     // Atomic address is the first or second parameter
-    Args.add(RValue::get(EmitCastToVoidPtr(Ptr)),
-             getContext().VoidPtrTy);
+    Args.add(RValue::get(EmitCastToVoidPtr(Ptr)), getContext().VoidPtrTy);
 
     std::string LibCallName;
     QualType RetTy;
@@ -490,11 +493,10 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E, llvm::Value *Dest) {
       LibCallName = "__atomic_compare_exchange";
       RetTy = getContext().BoolTy;
       HaveRetTy = true;
-      Args.add(RValue::get(EmitCastToVoidPtr(Val1)),
-               getContext().VoidPtrTy);
-      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val2, MemTy);
-      Args.add(RValue::get(Order),
-               getContext().IntTy);
+      Args.add(RValue::get(EmitCastToVoidPtr(Val1)), getContext().VoidPtrTy);
+      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val2, MemTy,
+                        E->getExprLoc());
+      Args.add(RValue::get(Order), getContext().IntTy);
       Order = OrderFail;
       break;
     // void __atomic_exchange(size_t size, void *mem, void *val, void *return,
@@ -504,7 +506,8 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E, llvm::Value *Dest) {
     case AtomicExpr::AO__atomic_exchange_n:
     case AtomicExpr::AO__atomic_exchange:
       LibCallName = "__atomic_exchange";
-      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy);
+      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy,
+                        E->getExprLoc());
       break;
     // void __atomic_store(size_t size, void *mem, void *val, int order)
     // void __atomic_store_N(T *mem, T val, int order)
@@ -514,7 +517,8 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E, llvm::Value *Dest) {
       LibCallName = "__atomic_store";
       RetTy = getContext().VoidTy;
       HaveRetTy = true;
-      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy);
+      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy,
+                        E->getExprLoc());
       break;
     // void __atomic_load(size_t size, void *mem, void *return, int order)
     // T __atomic_load_N(T *mem, int order)
@@ -527,31 +531,36 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E, llvm::Value *Dest) {
     case AtomicExpr::AO__c11_atomic_fetch_add:
     case AtomicExpr::AO__atomic_fetch_add:
       LibCallName = "__atomic_fetch_add";
-      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy);
+      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy,
+                        E->getExprLoc());
       break;
     // T __atomic_fetch_and_N(T *mem, T val, int order)
     case AtomicExpr::AO__c11_atomic_fetch_and:
     case AtomicExpr::AO__atomic_fetch_and:
       LibCallName = "__atomic_fetch_and";
-      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy);
+      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy,
+                        E->getExprLoc());
       break;
     // T __atomic_fetch_or_N(T *mem, T val, int order)
     case AtomicExpr::AO__c11_atomic_fetch_or:
     case AtomicExpr::AO__atomic_fetch_or:
       LibCallName = "__atomic_fetch_or";
-      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy);
+      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy,
+                        E->getExprLoc());
       break;
     // T __atomic_fetch_sub_N(T *mem, T val, int order)
     case AtomicExpr::AO__c11_atomic_fetch_sub:
     case AtomicExpr::AO__atomic_fetch_sub:
       LibCallName = "__atomic_fetch_sub";
-      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy);
+      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy,
+                        E->getExprLoc());
       break;
     // T __atomic_fetch_xor_N(T *mem, T val, int order)
     case AtomicExpr::AO__c11_atomic_fetch_xor:
     case AtomicExpr::AO__atomic_fetch_xor:
       LibCallName = "__atomic_fetch_xor";
-      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy);
+      AddDirectArgument(*this, Args, UseOptimizedLibcall, Val1, MemTy,
+                        E->getExprLoc());
       break;
     default: return EmitUnsupportedRValue(E, "atomic library call");
     }
@@ -585,7 +594,7 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E, llvm::Value *Dest) {
       return Res;
     if (E->getType()->isVoidType())
       return RValue::get(0);
-    return convertTempToRValue(Dest, E->getType());
+    return convertTempToRValue(Dest, E->getType(), E->getExprLoc());
   }
 
   bool IsStore = E->getOp() == AtomicExpr::AO__c11_atomic_store ||
@@ -640,7 +649,7 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E, llvm::Value *Dest) {
     }
     if (E->getType()->isVoidType())
       return RValue::get(0);
-    return convertTempToRValue(OrigDest, E->getType());
+    return convertTempToRValue(OrigDest, E->getType(), E->getExprLoc());
   }
 
   // Long case, when Order isn't obviously constant.
@@ -702,7 +711,7 @@ RValue CodeGenFunction::EmitAtomicExpr(AtomicExpr *E, llvm::Value *Dest) {
   Builder.SetInsertPoint(ContBB);
   if (E->getType()->isVoidType())
     return RValue::get(0);
-  return convertTempToRValue(OrigDest, E->getType());
+  return convertTempToRValue(OrigDest, E->getType(), E->getExprLoc());
 }
 
 llvm::Value *AtomicInfo::emitCastToAtomicIntPointer(llvm::Value *addr) const {
@@ -714,48 +723,30 @@ llvm::Value *AtomicInfo::emitCastToAtomicIntPointer(llvm::Value *addr) const {
 }
 
 RValue AtomicInfo::convertTempToRValue(llvm::Value *addr,
-                                       AggValueSlot resultSlot) const {
-  if (EvaluationKind == TEK_Aggregate) {
-    // Nothing to do if the result is ignored.
-    if (resultSlot.isIgnored()) return resultSlot.asRValue();
-
-    assert(resultSlot.getAddr() == addr || hasPadding());
-
-    // In these cases, we should have emitted directly into the result slot.
-    if (!hasPadding() || resultSlot.isValueOfAtomic())
-      return resultSlot.asRValue();
-
-    // Otherwise, fall into the common path.
-  }
+                                       AggValueSlot resultSlot,
+                                       SourceLocation loc) const {
+  if (EvaluationKind == TEK_Aggregate)
+    return resultSlot.asRValue();
 
   // Drill into the padding structure if we have one.
   if (hasPadding())
     addr = CGF.Builder.CreateStructGEP(addr, 0);
 
-  // If we're emitting to an aggregate, copy into the result slot.
-  if (EvaluationKind == TEK_Aggregate) {
-    CGF.EmitAggregateCopy(resultSlot.getAddr(), addr, getValueType(),
-                          resultSlot.isVolatile());
-    return resultSlot.asRValue();
-  }
-
   // Otherwise, just convert the temporary to an r-value using the
   // normal conversion routine.
-  return CGF.convertTempToRValue(addr, getValueType());
+  return CGF.convertTempToRValue(addr, getValueType(), loc);
 }
 
 /// Emit a load from an l-value of atomic type.  Note that the r-value
 /// we produce is an r-value of the atomic *value* type.
-RValue CodeGenFunction::EmitAtomicLoad(LValue src, AggValueSlot resultSlot) {
+RValue CodeGenFunction::EmitAtomicLoad(LValue src, SourceLocation loc,
+                                       AggValueSlot resultSlot) {
   AtomicInfo atomics(*this, src);
 
   // Check whether we should use a library call.
   if (atomics.shouldUseLibcall()) {
     llvm::Value *tempAddr;
-    if (resultSlot.isValueOfAtomic()) {
-      assert(atomics.getEvaluationKind() == TEK_Aggregate);
-      tempAddr = resultSlot.getPaddedAtomicAddr();
-    } else if (!resultSlot.isIgnored() && !atomics.hasPadding()) {
+    if (!resultSlot.isIgnored()) {
       assert(atomics.getEvaluationKind() == TEK_Aggregate);
       tempAddr = resultSlot.getAddr();
     } else {
@@ -776,7 +767,7 @@ RValue CodeGenFunction::EmitAtomicLoad(LValue src, AggValueSlot resultSlot) {
     emitAtomicLibcall(*this, "__atomic_load", getContext().VoidTy, args);
 
     // Produce the r-value.
-    return atomics.convertTempToRValue(tempAddr, resultSlot);
+    return atomics.convertTempToRValue(tempAddr, resultSlot, loc);
   }
 
   // Okay, we're doing this natively.
@@ -819,16 +810,10 @@ RValue CodeGenFunction::EmitAtomicLoad(LValue src, AggValueSlot resultSlot) {
   llvm::Value *temp;
   bool tempIsVolatile = false;
   CharUnits tempAlignment;
-  if (atomics.getEvaluationKind() == TEK_Aggregate &&
-      (!atomics.hasPadding() || resultSlot.isValueOfAtomic())) {
+  if (atomics.getEvaluationKind() == TEK_Aggregate) {
     assert(!resultSlot.isIgnored());
-    if (resultSlot.isValueOfAtomic()) {
-      temp = resultSlot.getPaddedAtomicAddr();
-      tempAlignment = atomics.getAtomicAlignment();
-    } else {
-      temp = resultSlot.getAddr();
-      tempAlignment = atomics.getValueAlignment();
-    }
+    temp = resultSlot.getAddr();
+    tempAlignment = atomics.getValueAlignment();
     tempIsVolatile = resultSlot.isVolatile();
   } else {
     temp = CreateMemTemp(atomics.getAtomicType(), "atomic-load-temp");
@@ -840,7 +825,7 @@ RValue CodeGenFunction::EmitAtomicLoad(LValue src, AggValueSlot resultSlot) {
   Builder.CreateAlignedStore(result, castTemp, tempAlignment.getQuantity())
     ->setVolatile(tempIsVolatile);
 
-  return atomics.convertTempToRValue(temp, resultSlot);
+  return atomics.convertTempToRValue(temp, resultSlot, loc);
 }
 
 
@@ -898,8 +883,7 @@ llvm::Value *AtomicInfo::materializeRValue(RValue rvalue) const {
 /// Note that the r-value is expected to be an r-value *of the atomic
 /// type*; this means that for aggregate r-values, it should include
 /// storage for any padding that was necessary.
-void CodeGenFunction::EmitAtomicStore(RValue rvalue, LValue dest,
-                                      bool isInit) {
+void CodeGenFunction::EmitAtomicStore(RValue rvalue, LValue dest, bool isInit) {
   // If this is an aggregate r-value, it should agree in type except
   // maybe for address-space qualification.
   assert(!rvalue.isAggregate() ||
@@ -996,13 +980,11 @@ void CodeGenFunction::EmitAtomicInit(Expr *init, LValue dest) {
   }
 
   case TEK_Aggregate: {
-    // Memset the buffer first if there's any possibility of
-    // uninitialized internal bits.
-    atomics.emitMemSetZeroIfNecessary(dest);
-
-    // HACK: whether the initializer actually has an atomic type
-    // doesn't really seem reliable right now.
+    // Fix up the destination if the initializer isn't an expression
+    // of atomic type.
+    bool Zeroed = false;
     if (!init->getType()->isAtomicType()) {
+      Zeroed = atomics.emitMemSetZeroIfNecessary(dest);
       dest = atomics.projectValue(dest);
     }
 
@@ -1010,7 +992,10 @@ void CodeGenFunction::EmitAtomicInit(Expr *init, LValue dest) {
     AggValueSlot slot = AggValueSlot::forLValue(dest,
                                         AggValueSlot::IsNotDestructed,
                                         AggValueSlot::DoesNotNeedGCBarriers,
-                                        AggValueSlot::IsNotAliased);
+                                        AggValueSlot::IsNotAliased,
+                                        Zeroed ? AggValueSlot::IsZeroed :
+                                                 AggValueSlot::IsNotZeroed);
+
     EmitAggExpr(init, slot);
     return;
   }