Merge clang, llvm, lld, lldb, compiler-rt and libc++ 5.0.0 release.

MFC r309126 (by emaste):

  Correct lld llvm-tblgen dependency file name

MFC r309169:

  Get rid of separate Subversion mergeinfo properties for llvm-dwarfdump
  and llvm-lto.  The mergeinfo confuses Subversion enormously, and these
  directories will just use the mergeinfo for llvm itself.

MFC r312765:

  Pull in r276136 from upstream llvm trunk (by Wei Mi):

    Use ValueOffsetPair to enhance value reuse during SCEV expansion.

    In D12090, the ExprValueMap was added to reuse existing value during
    SCEV expansion. However, const folding and sext/zext distribution can
    make the reuse still difficult.

    A simplified case is: suppose we know S1 expands to V1 in
    ExprValueMap, and
      S1 = S2 + C_a
      S3 = S2 + C_b
    where C_a and C_b are different SCEVConstants. Then we'd like to
    expand S3 as V1 - C_a + C_b instead of expanding S2 literally. It is
    helpful when S2 is a complex SCEV expr and S2 has no entry in
    ExprValueMap, which is usually caused by the fact that S3 is
    generated from S1 after const folding.

    In order to do that, we represent ExprValueMap as a mapping from SCEV
    to ValueOffsetPair. We will save both S1->{V1, 0} and S2->{V1, C_a}
    into the ExprValueMap when we create SCEV for V1. When S3 is
    expanded, it will first expand S2 to V1 - C_a because of S2->{V1,
    C_a} in the map, then expand S3 to V1 - C_a + C_b.

    Differential Revision: https://reviews.llvm.org/D21313

  This should fix assertion failures when building OpenCV >= 3.1.

  PR:		215649

MFC r312831:

  Revert r312765 for now, since it causes assertions when building
  lang/spidermonkey24.

  Reported by:	antoine
  PR:		215649

MFC r316511 (by jhb):

  Add an implementation of __ffssi2() derived from __ffsdi2().

  Newer versions of GCC include an __ffssi2() symbol in libgcc and the
  compiler can emit calls to it in generated code.  This is true for at
  least GCC 6.2 when compiling world for mips and mips64.

  Reviewed by:	jmallett, dim
  Sponsored by:	DARPA / AFRL
  Differential Revision:	https://reviews.freebsd.org/D10086

MFC r318601 (by adrian):

  [libcompiler-rt] add bswapdi2/bswapsi2

  This is required for mips gcc 6.3 userland to build/run.

  Reviewed by:	emaste, dim
  Approved by:	emaste
  Differential Revision:	https://reviews.freebsd.org/D10838

MFC r318884 (by emaste):

  lldb: map TRAP_CAP to a trace trap

  In the absense of a more specific handler for TRAP_CAP (generated by
  ENOTCAPABLE or ECAPMODE while in capability mode) treat it as a trace
  trap.

  Example usage (testing the bug in PR219173):

  % proccontrol -m trapcap lldb usr.bin/hexdump/obj/hexdump -- -Cv -s 1 /bin/ls
  ...
  (lldb) run
  Process 12980 launching
  Process 12980 launched: '.../usr.bin/hexdump/obj/hexdump' (x86_64)
  Process 12980 stopped
  * thread #1, stop reason = trace
      frame #0: 0x0000004b80c65f1a libc.so.7`__sys_lseek + 10
  ...

  In the future we should have LLDB control the trapcap procctl itself
  (as it does with ASLR), as well as report a specific stop reason.
  This change eliminates an assertion failure from LLDB for now.

MFC r319796:

  Remove a few unneeded files from libllvm, libclang and liblldb.

MFC r319885 (by emaste):

  lld: ELF: Fix ICF crash on absolute symbol relocations.

  If two sections contained relocations to absolute symbols with the same
  value we would crash when trying to access their sections. Add a check that
  both symbols point to sections before accessing their sections, and treat
  absolute symbols as equal if their values are equal.

  Obtained from:	LLD commit r292578

MFC r319918:

  Revert r319796 for now, it can cause undefined references when linking
  in some circumstances.

  Reported by:	Shawn Webb <shawn.webb@hardenedbsd.org>

MFC r319957 (by emaste):

  lld: Add armelf emulation mode

  Obtained from:	LLD r305375

MFC r321369:

  Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
  5.0.0 (trunk r308421).  Upstream has branched for the 5.0.0 release,
  which should be in about a month.  Please report bugs and regressions,
  so we can get them into the release.

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

MFC r321420:

  Add a few more object files to liblldb, which should solve errors when
  linking the lldb executable in some cases.  In particular, when the
  -ffunction-sections -fdata-sections options are turned off, or
  ineffective.

  Reported by:	Shawn Webb, Mark Millard

MFC r321433:

  Cleanup stale Options.inc files from the previous libllvm build for
  clang 4.0.0.  Otherwise, these can get included before the two newly
  generated ones (which are different) for clang 5.0.0.

  Reported by:	Mark Millard

MFC r321439 (by bdrewery):

  Move llvm Options.inc hack from r321433 for NO_CLEAN to lib/clang/libllvm.

  The files are only ever generated to .OBJDIR, not to WORLDTMP (as a
  sysroot) and are only ever included from a compilation.  So using
  a beforebuild target here removes the file before the compilation
  tries to include it.

MFC r321664:

  Pull in r308891 from upstream llvm trunk (by Benjamin Kramer):

    [CodeGenPrepare] Cut off FindAllMemoryUses if there are too many uses.

    This avoids excessive compile time. The case I'm looking at is
    Function.cpp from an old version of LLVM that still had the giant
    memcmp string matcher in it. Before r308322 this compiled in about 2
    minutes, after it, clang takes infinite* time to compile it. With
    this patch we're at 5 min, which is still bad but this is a
    pathological case.

    The cut off at 20 uses was chosen by looking at other cut-offs in LLVM
    for user scanning. It's probably too high, but does the job and is
    very unlikely to regress anything.

    Fixes PR33900.

    * I'm impatient and aborted after 15 minutes, on the bug report it was
      killed after 2h.

  Pull in r308986 from upstream llvm trunk (by Simon Pilgrim):

    [X86][CGP] Reduce memcmp() expansion to 2 load pairs (PR33914)

    D35067/rL308322 attempted to support up to 4 load pairs for memcmp
    inlining which resulted in regressions for some optimized libc memcmp
    implementations (PR33914).

    Until we can match these more optimal cases, this patch reduces the
    memcmp expansion to a maximum of 2 load pairs (which matches what we
    do for -Os).

    This patch should be considered for the 5.0.0 release branch as well

    Differential Revision: https://reviews.llvm.org/D35830

  These fix a hang (or extremely long compile time) when building older
  LLVM ports.

  Reported by:    antoine
  PR:             219139

MFC r321719:

  Pull in r309503 from upstream clang trunk (by Richard Smith):

    PR33902: Invalidate line number cache when adding more text to
    existing buffer.

    This led to crashes as the line number cache would report a bogus
    line number for a line of code, and we'd try to find a nonexistent
    column within the line when printing diagnostics.

  This fixes an assertion when building the graphics/champlain port.

  Reported by:	antoine, kwm
  PR:		219139

MFC r321723:

  Upgrade our copies of clang, llvm, lld and lldb to r309439 from the
  upstream release_50 branch.  This is just after upstream's 5.0.0-rc1.

MFC r322320:

  Upgrade our copies of clang, llvm and libc++ to r310316 from the
  upstream release_50 branch.

MFC r322326 (by emaste):

  lldb: Make i386-*-freebsd expression work on JIT path

  * Enable i386 ABI creation for freebsd
  * Added an extra argument in ABISysV_i386::PrepareTrivialCall for mmap
    syscall
  * Unlike linux, the last argument of mmap is actually 64-bit(off_t).
    This requires us to push an additional word for the higher order bits.
  * Prior to this change, ktrace dump will show mmap failures due to
    invalid argument coming from the 6th mmap argument.

  Submitted by:	Karnajit Wangkhem
  Differential Revision:	https://reviews.llvm.org/D34776

MFC r322360 (by emaste):

  lldb: Report inferior signals as signals, not exceptions, on FreeBSD

  This is the FreeBSD equivalent of LLVM r238549.

  This serves 2 purposes:

  * LLDB should handle inferior process signals SIGSEGV/SIGILL/SIGBUS/
    SIGFPE the way it is suppose to be handled. Prior to this fix these
    signals will neither create a coredump, nor exit from the debugger
    or work for signal handling scenario.
  * eInvalidCrashReason need not report "unknown crash reason" if we have
    a valid si_signo

  llvm.org/pr23699

  Patch by Karnajit Wangkhem

  Differential Revision:  https://reviews.llvm.org/D35223

  Submitted by:	Karnajit Wangkhem
  Obtained from:	LLVM r310591

MFC r322474 (by emaste):

  lld: Add `-z muldefs` option.

  Obtained from:	LLVM r310757

MFC r322740:

  Upgrade our copies of clang, llvm, lld and libc++ to r311219 from the
  upstream release_50 branch.

MFC r322855:

  Upgrade our copies of clang, llvm, lldb and compiler-rt to r311606 from
  the upstream release_50 branch.

  As of this version, lib/msun's trig test should also work correctly
  again (see bug 220989 for more information).

  PR:		220989

MFC r323112:

  Upgrade our copies of clang, llvm, lldb and compiler-rt to r312293 from
  the upstream release_50 branch.  This corresponds to 5.0.0 rc4.

  As of this version, the cad/stepcode port should now compile in a more
  reasonable time on i386 (see bug 221836 for more information).

  PR:		221836

MFC r323245:

  Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
  5.0.0 release (upstream r312559).

  Release notes for llvm, clang and lld will be available here soon:
  <http://releases.llvm.org/5.0.0/docs/ReleaseNotes.html>
  <http://releases.llvm.org/5.0.0/tools/clang/docs/ReleaseNotes.html>
  <http://releases.llvm.org/5.0.0/tools/lld/docs/ReleaseNotes.html>

  Relnotes:	yes

(cherry picked from commit 12cd91cf4c6b96a24427c0de5374916f2808d263)

1 files changed, 265 insertions, 92 deletions

diff --git a/contrib/llvm/tools/clang/lib/AST/ExprConstant.cpp b/contrib/llvm/tools/clang/lib/AST/ExprConstant.cpp
index 2c0fce9..df02e10 100644
--- a/contrib/llvm/tools/clang/lib/AST/ExprConstant.cpp
+++ b/contrib/llvm/tools/clang/lib/AST/ExprConstant.cpp
@@ -350,36 +350,49 @@ namespace {
       MostDerivedArraySize = 2;
       MostDerivedPathLength = Entries.size();
     }
-    void diagnosePointerArithmetic(EvalInfo &Info, const Expr *E, uint64_t N);
+    void diagnosePointerArithmetic(EvalInfo &Info, const Expr *E,
+                                   const APSInt &N);
     /// Add N to the address of this subobject.
-    void adjustIndex(EvalInfo &Info, const Expr *E, uint64_t N) {
-      if (Invalid) return;
+    void adjustIndex(EvalInfo &Info, const Expr *E, APSInt N) {
+      if (Invalid || !N) return;
+      uint64_t TruncatedN = N.extOrTrunc(64).getZExtValue();
       if (isMostDerivedAnUnsizedArray()) {
         // Can't verify -- trust that the user is doing the right thing (or if
         // not, trust that the caller will catch the bad behavior).
-        Entries.back().ArrayIndex += N;
-        return;
-      }
-      if (MostDerivedPathLength == Entries.size() &&
-          MostDerivedIsArrayElement) {
-        Entries.back().ArrayIndex += N;
-        if (Entries.back().ArrayIndex > getMostDerivedArraySize()) {
-          diagnosePointerArithmetic(Info, E, Entries.back().ArrayIndex);
-          setInvalid();
-        }
+        // FIXME: Should we reject if this overflows, at least?
+        Entries.back().ArrayIndex += TruncatedN;
         return;
       }
+
       // [expr.add]p4: For the purposes of these operators, a pointer to a
       // nonarray object behaves the same as a pointer to the first element of
       // an array of length one with the type of the object as its element type.
-      if (IsOnePastTheEnd && N == (uint64_t)-1)
-        IsOnePastTheEnd = false;
-      else if (!IsOnePastTheEnd && N == 1)
-        IsOnePastTheEnd = true;
-      else if (N != 0) {
-        diagnosePointerArithmetic(Info, E, uint64_t(IsOnePastTheEnd) + N);
+      bool IsArray = MostDerivedPathLength == Entries.size() &&
+                     MostDerivedIsArrayElement;
+      uint64_t ArrayIndex =
+          IsArray ? Entries.back().ArrayIndex : (uint64_t)IsOnePastTheEnd;
+      uint64_t ArraySize =
+          IsArray ? getMostDerivedArraySize() : (uint64_t)1;
+
+      if (N < -(int64_t)ArrayIndex || N > ArraySize - ArrayIndex) {
+        // Calculate the actual index in a wide enough type, so we can include
+        // it in the note.
+        N = N.extend(std::max<unsigned>(N.getBitWidth() + 1, 65));
+        (llvm::APInt&)N += ArrayIndex;
+        assert(N.ugt(ArraySize) && "bounds check failed for in-bounds index");
+        diagnosePointerArithmetic(Info, E, N);
         setInvalid();
+        return;
       }
+
+      ArrayIndex += TruncatedN;
+      assert(ArrayIndex <= ArraySize &&
+             "bounds check succeeded for out-of-bounds index");
+
+      if (IsArray)
+        Entries.back().ArrayIndex = ArrayIndex;
+      else
+        IsOnePastTheEnd = (ArrayIndex != 0);
     }
   };
 
@@ -413,6 +426,17 @@ namespace {
     /// Index - The call index of this call.
     unsigned Index;
 
+    // FIXME: Adding this to every 'CallStackFrame' may have a nontrivial impact
+    // on the overall stack usage of deeply-recursing constexpr evaluataions.
+    // (We should cache this map rather than recomputing it repeatedly.)
+    // But let's try this and see how it goes; we can look into caching the map
+    // as a later change.
+
+    /// LambdaCaptureFields - Mapping from captured variables/this to
+    /// corresponding data members in the closure class.
+    llvm::DenseMap<const VarDecl *, FieldDecl *> LambdaCaptureFields;
+    FieldDecl *LambdaThisCaptureField;
+
     CallStackFrame(EvalInfo &Info, SourceLocation CallLoc,
                    const FunctionDecl *Callee, const LValue *This,
                    APValue *Arguments);
@@ -712,6 +736,7 @@ namespace {
             if (!HasFoldFailureDiagnostic)
               break;
             // We've already failed to fold something. Keep that diagnostic.
+            LLVM_FALLTHROUGH;
           case EM_ConstantExpression:
           case EM_PotentialConstantExpression:
           case EM_ConstantExpressionUnevaluated:
@@ -1048,16 +1073,17 @@ bool SubobjectDesignator::checkSubobject(EvalInfo &Info, const Expr *E,
 }
 
 void SubobjectDesignator::diagnosePointerArithmetic(EvalInfo &Info,
-                                                    const Expr *E, uint64_t N) {
+                                                    const Expr *E,
+                                                    const APSInt &N) {
   // If we're complaining, we must be able to statically determine the size of
   // the most derived array.
   if (MostDerivedPathLength == Entries.size() && MostDerivedIsArrayElement)
     Info.CCEDiag(E, diag::note_constexpr_array_index)
-      << static_cast<int>(N) << /*array*/ 0
+      << N << /*array*/ 0
       << static_cast<unsigned>(getMostDerivedArraySize());
   else
     Info.CCEDiag(E, diag::note_constexpr_array_index)
-      << static_cast<int>(N) << /*non-array*/ 1;
+      << N << /*non-array*/ 1;
   setInvalid();
 }
 
@@ -1205,8 +1231,7 @@ namespace {
       IsNullPtr = V.isNullPointer();
     }
 
-    void set(APValue::LValueBase B, unsigned I = 0, bool BInvalid = false,
-             bool IsNullPtr_ = false, uint64_t Offset_ = 0) {
+    void set(APValue::LValueBase B, unsigned I = 0, bool BInvalid = false) {
 #ifndef NDEBUG
       // We only allow a few types of invalid bases. Enforce that here.
       if (BInvalid) {
@@ -1217,11 +1242,20 @@ namespace {
 #endif
 
       Base = B;
-      Offset = CharUnits::fromQuantity(Offset_);
+      Offset = CharUnits::fromQuantity(0);
       InvalidBase = BInvalid;
       CallIndex = I;
       Designator = SubobjectDesignator(getType(B));
-      IsNullPtr = IsNullPtr_;
+      IsNullPtr = false;
+    }
+
+    void setNull(QualType PointerTy, uint64_t TargetVal) {
+      Base = (Expr *)nullptr;
+      Offset = CharUnits::fromQuantity(TargetVal);
+      InvalidBase = false;
+      CallIndex = 0;
+      Designator = SubobjectDesignator(PointerTy->getPointeeType());
+      IsNullPtr = true;
     }
 
     void setInvalid(APValue::LValueBase B, unsigned I = 0) {
@@ -1273,14 +1307,24 @@ namespace {
     void clearIsNullPointer() {
       IsNullPtr = false;
     }
-    void adjustOffsetAndIndex(EvalInfo &Info, const Expr *E, uint64_t Index,
-                              CharUnits ElementSize) {
-      // Compute the new offset in the appropriate width.
-      Offset += Index * ElementSize;
-      if (Index && checkNullPointer(Info, E, CSK_ArrayIndex))
+    void adjustOffsetAndIndex(EvalInfo &Info, const Expr *E,
+                              const APSInt &Index, CharUnits ElementSize) {
+      // An index of 0 has no effect. (In C, adding 0 to a null pointer is UB,
+      // but we're not required to diagnose it and it's valid in C++.)
+      if (!Index)
+        return;
+
+      // Compute the new offset in the appropriate width, wrapping at 64 bits.
+      // FIXME: When compiling for a 32-bit target, we should use 32-bit
+      // offsets.
+      uint64_t Offset64 = Offset.getQuantity();
+      uint64_t ElemSize64 = ElementSize.getQuantity();
+      uint64_t Index64 = Index.extOrTrunc(64).getZExtValue();
+      Offset = CharUnits::fromQuantity(Offset64 + ElemSize64 * Index64);
+
+      if (checkNullPointer(Info, E, CSK_ArrayIndex))
         Designator.adjustIndex(Info, E, Index);
-      if (Index)
-        clearIsNullPointer();
+      clearIsNullPointer();
     }
     void adjustOffset(CharUnits N) {
       Offset += N;
@@ -1411,6 +1455,16 @@ static bool EvaluateAsRValue(EvalInfo &Info, const Expr *E, APValue &Result);
 // Misc utilities
 //===----------------------------------------------------------------------===//
 
+/// Negate an APSInt in place, converting it to a signed form if necessary, and
+/// preserving its value (by extending by up to one bit as needed).
+static void negateAsSigned(APSInt &Int) {
+  if (Int.isUnsigned() || Int.isMinSignedValue()) {
+    Int = Int.extend(Int.getBitWidth() + 1);
+    Int.setIsSigned(true);
+  }
+  Int = -Int;
+}
+
 /// Produce a string describing the given constexpr call.
 static void describeCall(CallStackFrame *Frame, raw_ostream &Out) {
   unsigned ArgIndex = 0;
@@ -1458,13 +1512,6 @@ static bool EvaluateIgnoredValue(EvalInfo &Info, const Expr *E) {
   return true;
 }
 
-/// Sign- or zero-extend a value to 64 bits. If it's already 64 bits, just
-/// return its existing value.
-static int64_t getExtValue(const APSInt &Value) {
-  return Value.isSigned() ? Value.getSExtValue()
-                          : static_cast<int64_t>(Value.getZExtValue());
-}
-
 /// Should this call expression be treated as a string literal?
 static bool IsStringLiteralCall(const CallExpr *E) {
   unsigned Builtin = E->getBuiltinCallee();
@@ -1617,6 +1664,19 @@ static bool CheckLValueConstantExpression(EvalInfo &Info, SourceLocation Loc,
   return true;
 }
 
+/// Member pointers are constant expressions unless they point to a
+/// non-virtual dllimport member function.
+static bool CheckMemberPointerConstantExpression(EvalInfo &Info,
+                                                 SourceLocation Loc,
+                                                 QualType Type,
+                                                 const APValue &Value) {
+  const ValueDecl *Member = Value.getMemberPointerDecl();
+  const auto *FD = dyn_cast_or_null<CXXMethodDecl>(Member);
+  if (!FD)
+    return true;
+  return FD->isVirtual() || !FD->hasAttr<DLLImportAttr>();
+}
+
 /// Check that this core constant expression is of literal type, and if not,
 /// produce an appropriate diagnostic.
 static bool CheckLiteralType(EvalInfo &Info, const Expr *E,
@@ -1709,6 +1769,9 @@ static bool CheckConstantExpression(EvalInfo &Info, SourceLocation DiagLoc,
     return CheckLValueConstantExpression(Info, DiagLoc, Type, LVal);
   }
 
+  if (Value.isMemberPointer())
+    return CheckMemberPointerConstantExpression(Info, DiagLoc, Type, Value);
+
   // Everything else is fine.
   return true;
 }
@@ -2220,7 +2283,7 @@ static bool HandleSizeof(EvalInfo &Info, SourceLocation Loc,
 /// \param Adjustment - The adjustment, in objects of type EltTy, to add.
 static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E,
                                         LValue &LVal, QualType EltTy,
-                                        int64_t Adjustment) {
+                                        APSInt Adjustment) {
   CharUnits SizeOfPointee;
   if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfPointee))
     return false;
@@ -2229,6 +2292,13 @@ static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E,
   return true;
 }
 
+static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E,
+                                        LValue &LVal, QualType EltTy,
+                                        int64_t Adjustment) {
+  return HandleLValueArrayAdjustment(Info, E, LVal, EltTy,
+                                     APSInt::get(Adjustment));
+}
+
 /// Update an lvalue to refer to a component of a complex number.
 /// \param Info - Information about the ongoing evaluation.
 /// \param LVal - The lvalue to be updated.
@@ -2247,6 +2317,10 @@ static bool HandleLValueComplexElement(EvalInfo &Info, const Expr *E,
   return true;
 }
 
+static bool handleLValueToRValueConversion(EvalInfo &Info, const Expr *Conv,
+                                           QualType Type, const LValue &LVal,
+                                           APValue &RVal);
+
 /// Try to evaluate the initializer for a variable declaration.
 ///
 /// \param Info   Information about the ongoing evaluation.
@@ -2258,6 +2332,7 @@ static bool HandleLValueComplexElement(EvalInfo &Info, const Expr *E,
 static bool evaluateVarDeclInit(EvalInfo &Info, const Expr *E,
                                 const VarDecl *VD, CallStackFrame *Frame,
                                 APValue *&Result) {
+
   // If this is a parameter to an active constexpr function call, perform
   // argument substitution.
   if (const ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(VD)) {
@@ -3191,9 +3266,9 @@ struct CompoundAssignSubobjectHandler {
       return false;
     }
 
-    int64_t Offset = getExtValue(RHS.getInt());
+    APSInt Offset = RHS.getInt();
     if (Opcode == BO_Sub)
-      Offset = -Offset;
+      negateAsSigned(Offset);
 
     LValue LVal;
     LVal.setFrom(Info.Ctx, Subobj);
@@ -4148,6 +4223,10 @@ static bool HandleFunctionCall(SourceLocation CallLoc,
       return false;
     This->moveInto(Result);
     return true;
+  } else if (MD && isLambdaCallOperator(MD)) {
+    // We're in a lambda; determine the lambda capture field maps.
+    MD->getParent()->getCaptureFields(Frame.LambdaCaptureFields,
+                                      Frame.LambdaThisCaptureField);
   }
 
   StmtResult Ret = {Result, ResultSlot};
@@ -4363,8 +4442,14 @@ private:
   bool HandleConditionalOperator(const ConditionalOperator *E) {
     bool BoolResult;
     if (!EvaluateAsBooleanCondition(E->getCond(), BoolResult, Info)) {
-      if (Info.checkingPotentialConstantExpression() && Info.noteFailure())
+      if (Info.checkingPotentialConstantExpression() && Info.noteFailure()) {
         CheckPotentialConstantConditional(E);
+        return false;
+      }
+      if (Info.noteFailure()) {
+        StmtVisitorTy::Visit(E->getTrueExpr());
+        StmtVisitorTy::Visit(E->getFalseExpr());
+      }
       return false;
     }
 
@@ -5009,6 +5094,33 @@ bool LValueExprEvaluator::VisitDeclRefExpr(const DeclRefExpr *E) {
 
 
 bool LValueExprEvaluator::VisitVarDecl(const Expr *E, const VarDecl *VD) {
+
+  // If we are within a lambda's call operator, check whether the 'VD' referred
+  // to within 'E' actually represents a lambda-capture that maps to a
+  // data-member/field within the closure object, and if so, evaluate to the
+  // field or what the field refers to.
+  if (Info.CurrentCall && isLambdaCallOperator(Info.CurrentCall->Callee)) {
+    if (auto *FD = Info.CurrentCall->LambdaCaptureFields.lookup(VD)) {
+      if (Info.checkingPotentialConstantExpression())
+        return false;
+      // Start with 'Result' referring to the complete closure object...
+      Result = *Info.CurrentCall->This;
+      // ... then update it to refer to the field of the closure object
+      // that represents the capture.
+      if (!HandleLValueMember(Info, E, Result, FD))
+        return false;
+      // And if the field is of reference type, update 'Result' to refer to what
+      // the field refers to.
+      if (FD->getType()->isReferenceType()) {
+        APValue RVal;
+        if (!handleLValueToRValueConversion(Info, E, FD->getType(), Result,
+                                            RVal))
+          return false;
+        Result.setFrom(Info.Ctx, RVal);
+      }
+      return true;
+    }
+  }
   CallStackFrame *Frame = nullptr;
   if (VD->hasLocalStorage() && Info.CurrentCall->Index > 1) {
     // Only if a local variable was declared in the function currently being
@@ -5155,15 +5267,19 @@ bool LValueExprEvaluator::VisitArraySubscriptExpr(const ArraySubscriptExpr *E) {
   if (E->getBase()->getType()->isVectorType())
     return Error(E);
 
-  if (!evaluatePointer(E->getBase(), Result))
-    return false;
+  bool Success = true;
+  if (!evaluatePointer(E->getBase(), Result)) {
+    if (!Info.noteFailure())
+      return false;
+    Success = false;
+  }
 
   APSInt Index;
   if (!EvaluateInteger(E->getIdx(), Index, Info))
     return false;
 
-  return HandleLValueArrayAdjustment(Info, E, Result, E->getType(),
-                                     getExtValue(Index));
+  return Success &&
+         HandleLValueArrayAdjustment(Info, E, Result, E->getType(), Index);
 }
 
 bool LValueExprEvaluator::VisitUnaryDeref(const UnaryOperator *E) {
@@ -5376,8 +5492,8 @@ public:
     return true;
   }
   bool ZeroInitialization(const Expr *E) {
-    auto Offset = Info.Ctx.getTargetNullPointerValue(E->getType());
-    Result.set((Expr*)nullptr, 0, false, true, Offset);
+    auto TargetVal = Info.Ctx.getTargetNullPointerValue(E->getType());
+    Result.setNull(E->getType(), TargetVal);
     return true;
   }
 
@@ -5386,8 +5502,11 @@ public:
   bool VisitUnaryAddrOf(const UnaryOperator *E);
   bool VisitObjCStringLiteral(const ObjCStringLiteral *E)
       { return Success(E); }
-  bool VisitObjCBoxedExpr(const ObjCBoxedExpr *E)
-      { return Success(E); }
+  bool VisitObjCBoxedExpr(const ObjCBoxedExpr *E) {
+    if (Info.noteFailure())
+      EvaluateIgnoredValue(Info, E->getSubExpr());
+    return Error(E);
+  }
   bool VisitAddrLabelExpr(const AddrLabelExpr *E)
       { return Success(E); }
   bool VisitCallExpr(const CallExpr *E);
@@ -5409,6 +5528,27 @@ public:
       return false;
     }
     Result = *Info.CurrentCall->This;
+    // If we are inside a lambda's call operator, the 'this' expression refers
+    // to the enclosing '*this' object (either by value or reference) which is
+    // either copied into the closure object's field that represents the '*this'
+    // or refers to '*this'.
+    if (isLambdaCallOperator(Info.CurrentCall->Callee)) {
+      // Update 'Result' to refer to the data member/field of the closure object
+      // that represents the '*this' capture.
+      if (!HandleLValueMember(Info, E, Result,
+                             Info.CurrentCall->LambdaThisCaptureField)) 
+        return false;
+      // If we captured '*this' by reference, replace the field with its referent.
+      if (Info.CurrentCall->LambdaThisCaptureField->getType()
+              ->isPointerType()) {
+        APValue RVal;
+        if (!handleLValueToRValueConversion(Info, E, E->getType(), Result,
+                                            RVal))
+          return false;
+
+        Result.setFrom(Info.Ctx, RVal);
+      }
+    }
     return true;
   }
 
@@ -5440,13 +5580,11 @@ bool PointerExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
   if (!EvaluateInteger(IExp, Offset, Info) || !EvalPtrOK)
     return false;
 
-  int64_t AdditionalOffset = getExtValue(Offset);
   if (E->getOpcode() == BO_Sub)
-    AdditionalOffset = -AdditionalOffset;
+    negateAsSigned(Offset);
 
   QualType Pointee = PExp->getType()->castAs<PointerType>()->getPointeeType();
-  return HandleLValueArrayAdjustment(Info, E, Result, Pointee,
-                                     AdditionalOffset);
+  return HandleLValueArrayAdjustment(Info, E, Result, Pointee, Offset);
 }
 
 bool PointerExprEvaluator::VisitUnaryAddrOf(const UnaryOperator *E) {
@@ -5576,6 +5714,8 @@ static CharUnits GetAlignOfType(EvalInfo &Info, QualType T) {
     T = Ref->getPointeeType();
 
   // __alignof is defined to return the preferred alignment.
+  if (T.getQualifiers().hasUnaligned())
+    return CharUnits::One();
   return Info.Ctx.toCharUnitsFromBits(
     Info.Ctx.getPreferredTypeAlign(T.getTypePtr()));
 }
@@ -5640,14 +5780,14 @@ bool PointerExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
     APSInt Alignment;
     if (!EvaluateInteger(E->getArg(1), Alignment, Info))
       return false;
-    CharUnits Align = CharUnits::fromQuantity(getExtValue(Alignment));
+    CharUnits Align = CharUnits::fromQuantity(Alignment.getZExtValue());
 
     if (E->getNumArgs() > 2) {
       APSInt Offset;
       if (!EvaluateInteger(E->getArg(2), Offset, Info))
         return false;
 
-      int64_t AdditionalOffset = -getExtValue(Offset);
+      int64_t AdditionalOffset = -Offset.getZExtValue();
       OffsetResult.Offset += CharUnits::fromQuantity(AdditionalOffset);
     }
 
@@ -5664,12 +5804,11 @@ bool PointerExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
 
       if (BaseAlignment < Align) {
         Result.Designator.setInvalid();
-        // FIXME: Quantities here cast to integers because the plural modifier
-        // does not work on APSInts yet.
+        // FIXME: Add support to Diagnostic for long / long long.
         CCEDiag(E->getArg(0),
                 diag::note_constexpr_baa_insufficient_alignment) << 0
-          << (int) BaseAlignment.getQuantity()
-          << (unsigned) getExtValue(Alignment);
+          << (unsigned)BaseAlignment.getQuantity()
+          << (unsigned)Align.getQuantity();
         return false;
       }
     }
@@ -5677,18 +5816,14 @@ bool PointerExprEvaluator::VisitBuiltinCallExpr(const CallExpr *E,
     // The offset must also have the correct alignment.
     if (OffsetResult.Offset.alignTo(Align) != OffsetResult.Offset) {
       Result.Designator.setInvalid();
-      APSInt Offset(64, false);
-      Offset = OffsetResult.Offset.getQuantity();
-
-      if (OffsetResult.Base)
-        CCEDiag(E->getArg(0),
-                diag::note_constexpr_baa_insufficient_alignment) << 1
-          << (int) getExtValue(Offset) << (unsigned) getExtValue(Alignment);
-      else
-        CCEDiag(E->getArg(0),
-                diag::note_constexpr_baa_value_insufficient_alignment)
-          << Offset << (unsigned) getExtValue(Alignment);
 
+      (OffsetResult.Base
+           ? CCEDiag(E->getArg(0),
+                     diag::note_constexpr_baa_insufficient_alignment) << 1
+           : CCEDiag(E->getArg(0),
+                     diag::note_constexpr_baa_value_insufficient_alignment))
+        << (int)OffsetResult.Offset.getQuantity()
+        << (unsigned)Align.getQuantity();
       return false;
     }
 
@@ -6245,14 +6380,40 @@ bool RecordExprEvaluator::VisitLambdaExpr(const LambdaExpr *E) {
   if (ClosureClass->isInvalidDecl()) return false;
 
   if (Info.checkingPotentialConstantExpression()) return true;
-  if (E->capture_size()) {
-    Info.FFDiag(E, diag::note_unimplemented_constexpr_lambda_feature_ast)
-        << "can not evaluate lambda expressions with captures";
-    return false;
+  
+  const size_t NumFields =
+      std::distance(ClosureClass->field_begin(), ClosureClass->field_end());
+
+  assert(NumFields == (size_t)std::distance(E->capture_init_begin(),
+                                            E->capture_init_end()) &&
+         "The number of lambda capture initializers should equal the number of "
+         "fields within the closure type");
+
+  Result = APValue(APValue::UninitStruct(), /*NumBases*/0, NumFields);
+  // Iterate through all the lambda's closure object's fields and initialize
+  // them.
+  auto *CaptureInitIt = E->capture_init_begin();
+  const LambdaCapture *CaptureIt = ClosureClass->captures_begin();
+  bool Success = true;
+  for (const auto *Field : ClosureClass->fields()) {
+    assert(CaptureInitIt != E->capture_init_end());
+    // Get the initializer for this field
+    Expr *const CurFieldInit = *CaptureInitIt++;
+    
+    // If there is no initializer, either this is a VLA or an error has
+    // occurred.
+    if (!CurFieldInit)
+      return Error(E);
+
+    APValue &FieldVal = Result.getStructField(Field->getFieldIndex());
+    if (!EvaluateInPlace(FieldVal, Info, This, CurFieldInit)) {
+      if (!Info.keepEvaluatingAfterFailure())
+        return false;
+      Success = false;
+    }
+    ++CaptureIt;
   }
-  // FIXME: Implement captures.
-  Result = APValue(APValue::UninitStruct(), /*NumBases*/0, /*NumFields*/0);
-  return true;
+  return Success;
 }
 
 static bool EvaluateRecord(const Expr *E, const LValue &This,
@@ -6971,7 +7132,6 @@ static int EvaluateBuiltinClassifyType(const CallExpr *E,
     case BuiltinType::OCLEvent:
     case BuiltinType::OCLClkEvent:
     case BuiltinType::OCLQueue:
-    case BuiltinType::OCLNDRange:
     case BuiltinType::OCLReserveID:
     case BuiltinType::Dependent:
       llvm_unreachable("CallExpr::isBuiltinClassifyType(): unimplemented type");
@@ -7030,6 +7190,7 @@ static int EvaluateBuiltinClassifyType(const CallExpr *E,
   case Type::Vector:
   case Type::ExtVector:
   case Type::Auto:
+  case Type::DeducedTemplateSpecialization:
   case Type::ObjCObject:
   case Type::ObjCInterface:
   case Type::ObjCObjectPointer:
@@ -7948,6 +8109,19 @@ bool DataRecursiveIntBinOpEvaluator::
   return true;
 }
 
+static void addOrSubLValueAsInteger(APValue &LVal, const APSInt &Index,
+                                    bool IsSub) {
+  // Compute the new offset in the appropriate width, wrapping at 64 bits.
+  // FIXME: When compiling for a 32-bit target, we should use 32-bit
+  // offsets.
+  assert(!LVal.hasLValuePath() && "have designator for integer lvalue");
+  CharUnits &Offset = LVal.getLValueOffset();
+  uint64_t Offset64 = Offset.getQuantity();
+  uint64_t Index64 = Index.extOrTrunc(64).getZExtValue();
+  Offset = CharUnits::fromQuantity(IsSub ? Offset64 - Index64
+                                         : Offset64 + Index64);
+}
+
 bool DataRecursiveIntBinOpEvaluator::
        VisitBinOp(const EvalResult &LHSResult, const EvalResult &RHSResult,
                   const BinaryOperator *E, APValue &Result) {
@@ -7994,12 +8168,7 @@ bool DataRecursiveIntBinOpEvaluator::
   // Handle cases like (unsigned long)&a + 4.
   if (E->isAdditiveOp() && LHSVal.isLValue() && RHSVal.isInt()) {
     Result = LHSVal;
-    CharUnits AdditionalOffset =
-        CharUnits::fromQuantity(RHSVal.getInt().getZExtValue());
-    if (E->getOpcode() == BO_Add)
-      Result.getLValueOffset() += AdditionalOffset;
-    else
-      Result.getLValueOffset() -= AdditionalOffset;
+    addOrSubLValueAsInteger(Result, RHSVal.getInt(), E->getOpcode() == BO_Sub);
     return true;
   }
   
@@ -8007,8 +8176,7 @@ bool DataRecursiveIntBinOpEvaluator::
   if (E->getOpcode() == BO_Add &&
       RHSVal.isLValue() && LHSVal.isInt()) {
     Result = RHSVal;
-    Result.getLValueOffset() +=
-        CharUnits::fromQuantity(LHSVal.getInt().getZExtValue());
+    addOrSubLValueAsInteger(Result, LHSVal.getInt(), /*IsSub*/false);
     return true;
   }
   
@@ -9352,7 +9520,7 @@ bool ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
   case BO_Mul:
     if (Result.isComplexFloat()) {
       // This is an implementation of complex multiplication according to the
-      // constraints laid out in C11 Annex G. The implemantion uses the
+      // constraints laid out in C11 Annex G. The implemention uses the
       // following naming scheme:
       //   (a + ib) * (c + id)
       ComplexValue LHS = Result;
@@ -9433,7 +9601,7 @@ bool ComplexExprEvaluator::VisitBinaryOperator(const BinaryOperator *E) {
   case BO_Div:
     if (Result.isComplexFloat()) {
       // This is an implementation of complex division according to the
-      // constraints laid out in C11 Annex G. The implemantion uses the
+      // constraints laid out in C11 Annex G. The implemention uses the
       // following naming scheme:
       //   (a + ib) / (c + id)
       ComplexValue LHS = Result;
@@ -9610,6 +9778,8 @@ public:
 
   bool Success(const APValue &V, const Expr *e) { return true; }
 
+  bool ZeroInitialization(const Expr *E) { return true; }
+
   bool VisitCastExpr(const CastExpr *E) {
     switch (E->getCastKind()) {
     default:
@@ -9945,7 +10115,7 @@ bool Expr::EvalResult::isGlobalLValue() const {
 // Note that to reduce code duplication, this helper does no evaluation
 // itself; the caller checks whether the expression is evaluatable, and
 // in the rare cases where CheckICE actually cares about the evaluated
-// value, it calls into Evalute.
+// value, it calls into Evaluate.
 
 namespace {
 
@@ -10067,6 +10237,7 @@ static ICEDiag CheckICE(const Expr* E, const ASTContext &Ctx) {
   case Expr::LambdaExprClass:
   case Expr::CXXFoldExprClass:
   case Expr::CoawaitExprClass:
+  case Expr::DependentCoawaitExprClass:
   case Expr::CoyieldExprClass:
     return ICEDiag(IK_NotICE, E->getLocStart());
 
@@ -10169,6 +10340,7 @@ static ICEDiag CheckICE(const Expr* E, const ASTContext &Ctx) {
     }
 
     // OffsetOf falls through here.
+    LLVM_FALLTHROUGH;
   }
   case Expr::OffsetOfExprClass: {
     // Note that per C99, offsetof must be an ICE. And AFAIK, using
@@ -10271,6 +10443,7 @@ static ICEDiag CheckICE(const Expr* E, const ASTContext &Ctx) {
       return Worst(LHSResult, RHSResult);
     }
     }
+    LLVM_FALLTHROUGH;
   }
   case Expr::ImplicitCastExprClass:
   case Expr::CStyleCastExprClass: