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, 208 insertions, 55 deletions

diff --git a/contrib/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/contrib/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
index ec75dd2..88bb69b 100644
--- a/contrib/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
+++ b/contrib/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp
@@ -173,14 +173,14 @@ Instruction *InstCombiner::OptAndOp(Instruction *Op,
       // Adding a one to a single bit bit-field should be turned into an XOR
       // of the bit.  First thing to check is to see if this AND is with a
       // single bit constant.
-      const APInt &AndRHSV = cast<ConstantInt>(AndRHS)->getValue();
+      const APInt &AndRHSV = AndRHS->getValue();
 
       // If there is only one bit set.
       if (AndRHSV.isPowerOf2()) {
         // Ok, at this point, we know that we are masking the result of the
         // ADD down to exactly one bit.  If the constant we are adding has
         // no bits set below this bit, then we can eliminate the ADD.
-        const APInt& AddRHS = cast<ConstantInt>(OpRHS)->getValue();
+        const APInt& AddRHS = OpRHS->getValue();
 
         // Check to see if any bits below the one bit set in AndRHSV are set.
         if ((AddRHS & (AndRHSV-1)) == 0) {
@@ -209,8 +209,7 @@ Instruction *InstCombiner::OptAndOp(Instruction *Op,
     uint32_t BitWidth = AndRHS->getType()->getBitWidth();
     uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
     APInt ShlMask(APInt::getHighBitsSet(BitWidth, BitWidth-OpRHSVal));
-    ConstantInt *CI = ConstantInt::get(AndRHS->getContext(),
-                                       AndRHS->getValue() & ShlMask);
+    ConstantInt *CI = Builder->getInt(AndRHS->getValue() & ShlMask);
 
     if (CI->getValue() == ShlMask)
       // Masking out bits that the shift already masks.
@@ -230,8 +229,7 @@ Instruction *InstCombiner::OptAndOp(Instruction *Op,
     uint32_t BitWidth = AndRHS->getType()->getBitWidth();
     uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
     APInt ShrMask(APInt::getLowBitsSet(BitWidth, BitWidth - OpRHSVal));
-    ConstantInt *CI = ConstantInt::get(Op->getContext(),
-                                       AndRHS->getValue() & ShrMask);
+    ConstantInt *CI = Builder->getInt(AndRHS->getValue() & ShrMask);
 
     if (CI->getValue() == ShrMask)
       // Masking out bits that the shift already masks.
@@ -251,8 +249,7 @@ Instruction *InstCombiner::OptAndOp(Instruction *Op,
       uint32_t BitWidth = AndRHS->getType()->getBitWidth();
       uint32_t OpRHSVal = OpRHS->getLimitedValue(BitWidth);
       APInt ShrMask(APInt::getLowBitsSet(BitWidth, BitWidth - OpRHSVal));
-      Constant *C = ConstantInt::get(Op->getContext(),
-                                     AndRHS->getValue() & ShrMask);
+      Constant *C = Builder->getInt(AndRHS->getValue() & ShrMask);
       if (C == AndRHS) {          // Masking out bits shifted in.
         // (Val ashr C1) & C2 -> (Val lshr C1) & C2
         // Make the argument unsigned.
@@ -279,7 +276,7 @@ Value *InstCombiner::InsertRangeTest(Value *V, Constant *Lo, Constant *Hi,
 
   if (Inside) {
     if (Lo == Hi)  // Trivially false.
-      return ConstantInt::getFalse(V->getContext());
+      return Builder->getFalse();
 
     // V >= Min && V < Hi --> V < Hi
     if (cast<ConstantInt>(Lo)->isMinValue(isSigned)) {
@@ -296,7 +293,7 @@ Value *InstCombiner::InsertRangeTest(Value *V, Constant *Lo, Constant *Hi,
   }
 
   if (Lo == Hi)  // Trivially true.
-    return ConstantInt::getTrue(V->getContext());
+    return Builder->getTrue();
 
   // V < Min || V >= Hi -> V > Hi-1
   Hi = SubOne(cast<ConstantInt>(Hi));
@@ -491,6 +488,26 @@ static unsigned getTypeOfMaskedICmp(Value* A, Value* B, Value* C,
   return result;
 }
 
+/// Convert an analysis of a masked ICmp into its equivalent if all boolean
+/// operations had the opposite sense. Since each "NotXXX" flag (recording !=)
+/// is adjacent to the corresponding normal flag (recording ==), this just
+/// involves swapping those bits over.
+static unsigned conjugateICmpMask(unsigned Mask) {
+  unsigned NewMask;
+  NewMask = (Mask & (FoldMskICmp_AMask_AllOnes | FoldMskICmp_BMask_AllOnes |
+                     FoldMskICmp_Mask_AllZeroes | FoldMskICmp_AMask_Mixed |
+                     FoldMskICmp_BMask_Mixed))
+            << 1;
+
+  NewMask |=
+      (Mask & (FoldMskICmp_AMask_NotAllOnes | FoldMskICmp_BMask_NotAllOnes |
+               FoldMskICmp_Mask_NotAllZeroes | FoldMskICmp_AMask_NotMixed |
+               FoldMskICmp_BMask_NotMixed))
+      >> 1;
+
+  return NewMask;
+}
+
 /// decomposeBitTestICmp - Decompose an icmp into the form ((X & Y) pred Z)
 /// if possible. The returned predicate is either == or !=. Returns false if
 /// decomposition fails.
@@ -551,14 +568,22 @@ static unsigned foldLogOpOfMaskedICmpsHelper(Value*& A,
     L21 = L22 = L1 = 0;
   } else {
     // Look for ANDs in the LHS icmp.
-    if (match(L1, m_And(m_Value(L11), m_Value(L12)))) {
-      if (!match(L2, m_And(m_Value(L21), m_Value(L22))))
-        L21 = L22 = 0;
-    } else {
-      if (!match(L2, m_And(m_Value(L11), m_Value(L12))))
-        return 0;
-      std::swap(L1, L2);
+    if (!L1->getType()->isIntegerTy()) {
+      // You can icmp pointers, for example. They really aren't masks.
+      L11 = L12 = 0;
+    } else if (!match(L1, m_And(m_Value(L11), m_Value(L12)))) {
+      // Any icmp can be viewed as being trivially masked; if it allows us to
+      // remove one, it's worth it.
+      L11 = L1;
+      L12 = Constant::getAllOnesValue(L1->getType());
+    }
+
+    if (!L2->getType()->isIntegerTy()) {
+      // You can icmp pointers, for example. They really aren't masks.
       L21 = L22 = 0;
+    } else if (!match(L2, m_And(m_Value(L21), m_Value(L22)))) {
+      L21 = L2;
+      L22 = Constant::getAllOnesValue(L2->getType());
     }
   }
 
@@ -579,7 +604,14 @@ static unsigned foldLogOpOfMaskedICmpsHelper(Value*& A,
       return 0;
     }
     E = R2; R1 = 0; ok = true;
-  } else if (match(R1, m_And(m_Value(R11), m_Value(R12)))) {
+  } else if (R1->getType()->isIntegerTy()) {
+    if (!match(R1, m_And(m_Value(R11), m_Value(R12)))) {
+      // As before, model no mask as a trivial mask if it'll let us do an
+      // optimisation.
+      R11 = R1;
+      R12 = Constant::getAllOnesValue(R1->getType());
+    }
+
     if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) {
       A = R11; D = R12; E = R2; ok = true;
     } else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
@@ -592,7 +624,12 @@ static unsigned foldLogOpOfMaskedICmpsHelper(Value*& A,
     return 0;
 
   // Look for ANDs in on the right side of the RHS icmp.
-  if (!ok && match(R2, m_And(m_Value(R11), m_Value(R12)))) {
+  if (!ok && R2->getType()->isIntegerTy()) {
+    if (!match(R2, m_And(m_Value(R11), m_Value(R12)))) {
+      R11 = R2;
+      R12 = Constant::getAllOnesValue(R2->getType());
+    }
+
     if (R11 == L11 || R11 == L12 || R11 == L21 || R11 == L22) {
       A = R11; D = R12; E = R1; ok = true;
     } else if (R12 == L11 || R12 == L12 || R12 == L21 || R12 == L22) {
@@ -621,8 +658,7 @@ static unsigned foldLogOpOfMaskedICmpsHelper(Value*& A,
 /// foldLogOpOfMaskedICmps:
 /// try to fold (icmp(A & B) ==/!= C) &/| (icmp(A & D) ==/!= E)
 /// into a single (icmp(A & X) ==/!= Y)
-static Value* foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS,
-                                     ICmpInst::Predicate NEWCC,
+static Value* foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS, bool IsAnd,
                                      llvm::InstCombiner::BuilderTy* Builder) {
   Value *A = 0, *B = 0, *C = 0, *D = 0, *E = 0;
   ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
@@ -632,8 +668,24 @@ static Value* foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS,
   assert(ICmpInst::isEquality(LHSCC) && ICmpInst::isEquality(RHSCC) &&
          "foldLogOpOfMaskedICmpsHelper must return an equality predicate.");
 
-  if (NEWCC == ICmpInst::ICMP_NE)
-    mask >>= 1; // treat "Not"-states as normal states
+  // In full generality:
+  //     (icmp (A & B) Op C) | (icmp (A & D) Op E)
+  // ==  ![ (icmp (A & B) !Op C) & (icmp (A & D) !Op E) ]
+  //
+  // If the latter can be converted into (icmp (A & X) Op Y) then the former is
+  // equivalent to (icmp (A & X) !Op Y).
+  //
+  // Therefore, we can pretend for the rest of this function that we're dealing
+  // with the conjunction, provided we flip the sense of any comparisons (both
+  // input and output).
+
+  // In most cases we're going to produce an EQ for the "&&" case.
+  ICmpInst::Predicate NEWCC = IsAnd ? ICmpInst::ICMP_EQ : ICmpInst::ICMP_NE;
+  if (!IsAnd) {
+    // Convert the masking analysis into its equivalent with negated
+    // comparisons.
+    mask = conjugateICmpMask(mask);
+  }
 
   if (mask & FoldMskICmp_Mask_AllZeroes) {
     // (icmp eq (A & B), 0) & (icmp eq (A & D), 0)
@@ -660,6 +712,40 @@ static Value* foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS,
     Value* newAnd = Builder->CreateAnd(A, newAnd1);
     return Builder->CreateICmp(NEWCC, newAnd, A);
   }
+
+  // Remaining cases assume at least that B and D are constant, and depend on
+  // their actual values. This isn't strictly, necessary, just a "handle the
+  // easy cases for now" decision.
+  ConstantInt *BCst = dyn_cast<ConstantInt>(B);
+  if (BCst == 0) return 0;
+  ConstantInt *DCst = dyn_cast<ConstantInt>(D);
+  if (DCst == 0) return 0;
+
+  if (mask & (FoldMskICmp_Mask_NotAllZeroes | FoldMskICmp_BMask_NotAllOnes)) {
+    // (icmp ne (A & B), 0) & (icmp ne (A & D), 0) and
+    // (icmp ne (A & B), B) & (icmp ne (A & D), D)
+    //     -> (icmp ne (A & B), 0) or (icmp ne (A & D), 0)
+    // Only valid if one of the masks is a superset of the other (check "B&D" is
+    // the same as either B or D).
+    APInt NewMask = BCst->getValue() & DCst->getValue();
+
+    if (NewMask == BCst->getValue())
+      return LHS;
+    else if (NewMask == DCst->getValue())
+      return RHS;
+  }
+  if (mask & FoldMskICmp_AMask_NotAllOnes) {
+    // (icmp ne (A & B), B) & (icmp ne (A & D), D)
+    //     -> (icmp ne (A & B), A) or (icmp ne (A & D), A)
+    // Only valid if one of the masks is a superset of the other (check "B|D" is
+    // the same as either B or D).
+    APInt NewMask = BCst->getValue() | DCst->getValue();
+
+    if (NewMask == BCst->getValue())
+      return LHS;
+    else if (NewMask == DCst->getValue())
+      return RHS;
+  }
   if (mask & FoldMskICmp_BMask_Mixed) {
     // (icmp eq (A & B), C) & (icmp eq (A & D), E)
     // We already know that B & C == C && D & E == E.
@@ -668,14 +754,9 @@ static Value* foldLogOpOfMaskedICmps(ICmpInst *LHS, ICmpInst *RHS,
     // contradict, then we can transform to
     // -> (icmp eq (A & (B|D)), (C|E))
     // Currently, we only handle the case of B, C, D, and E being constant.
-    ConstantInt *BCst = dyn_cast<ConstantInt>(B);
-    if (BCst == 0) return 0;
-    ConstantInt *DCst = dyn_cast<ConstantInt>(D);
-    if (DCst == 0) return 0;
     // we can't simply use C and E, because we might actually handle
     //   (icmp ne (A & B), B) & (icmp eq (A & D), D)
     // with B and D, having a single bit set
-
     ConstantInt *CCst = dyn_cast<ConstantInt>(C);
     if (CCst == 0) return 0;
     if (LHSCC != NEWCC)
@@ -718,7 +799,7 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
   }
 
   // handle (roughly):  (icmp eq (A & B), C) & (icmp eq (A & D), E)
-  if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, ICmpInst::ICMP_EQ, Builder))
+  if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, true, Builder))
     return V;
 
   // This only handles icmp of constants: (icmp1 A, C1) & (icmp2 B, C2).
@@ -852,10 +933,15 @@ Value *InstCombiner::FoldAndOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
     case ICmpInst::ICMP_SGT:        // (X != 13 & X s> 15) -> X s> 15
       return RHS;
     case ICmpInst::ICMP_NE:
+      // Special case to get the ordering right when the values wrap around
+      // zero.
+      if (LHSCst->getValue() == 0 && RHSCst->getValue().isAllOnesValue())
+        std::swap(LHSCst, RHSCst);
       if (LHSCst == SubOne(RHSCst)){// (X != 13 & X != 14) -> X-13 >u 1
         Constant *AddCST = ConstantExpr::getNeg(LHSCst);
         Value *Add = Builder->CreateAdd(Val, AddCST, Val->getName()+".off");
-        return Builder->CreateICmpUGT(Add, ConstantInt::get(Add->getType(), 1));
+        return Builder->CreateICmpUGT(Add, ConstantInt::get(Add->getType(), 1),
+                                      Val->getName()+".cmp");
       }
       break;                        // (X != 13 & X != 15) -> no change
     }
@@ -943,7 +1029,7 @@ Value *InstCombiner::FoldAndOfFCmps(FCmpInst *LHS, FCmpInst *RHS) {
         // If either of the constants are nans, then the whole thing returns
         // false.
         if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN())
-          return ConstantInt::getFalse(LHS->getContext());
+          return Builder->getFalse();
         return Builder->CreateFCmpORD(LHS->getOperand(0), RHS->getOperand(0));
       }
 
@@ -1302,7 +1388,7 @@ Instruction *InstCombiner::visitAnd(BinaryOperator &I) {
 /// always in the local (OverallLeftShift) coordinate space.
 ///
 static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask,
-                              SmallVector<Value*, 8> &ByteValues) {
+                              SmallVectorImpl<Value *> &ByteValues) {
   if (Instruction *I = dyn_cast<Instruction>(V)) {
     // If this is an or instruction, it may be an inner node of the bswap.
     if (I->getOpcode() == Instruction::Or) {
@@ -1380,7 +1466,7 @@ static bool CollectBSwapParts(Value *V, int OverallLeftShift, uint32_t ByteMask,
   // into a byteswap.  At least one of the two bytes would not be aligned with
   // their ultimate destination.
   if (!isPowerOf2_32(ByteMask)) return true;
-  unsigned InputByteNo = CountTrailingZeros_32(ByteMask);
+  unsigned InputByteNo = countTrailingZeros(ByteMask);
 
   // 2) The input and ultimate destinations must line up: if byte 3 of an i32
   // is demanded, it needs to go into byte 0 of the result.  This means that the
@@ -1457,10 +1543,60 @@ static Instruction *MatchSelectFromAndOr(Value *A, Value *B,
   return 0;
 }
 
+/// IsOneHotValue - Returns true for "one-hot" values (values where at most
+/// one bit can be set).
+static bool IsOneHotValue(Value *V) {
+  // Match 1<<K.
+  if (BinaryOperator *BO = dyn_cast<BinaryOperator>(V))
+    if (BO->getOpcode() == Instruction::Shl) {
+      ConstantInt *One = dyn_cast<ConstantInt>(BO->getOperand(0));
+      return One && One->isOne();
+    }
+
+  // Check for power of two integer constants.
+  if (ConstantInt *K = dyn_cast<ConstantInt>(V))
+    return K->getValue().isPowerOf2();
+
+  return false;
+}
+
 /// FoldOrOfICmps - Fold (icmp)|(icmp) if possible.
 Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
   ICmpInst::Predicate LHSCC = LHS->getPredicate(), RHSCC = RHS->getPredicate();
 
+  // Fold (iszero(A & K1) | iszero(A & K2)) ->  (A & (K1 | K2)) != (K1 | K2)
+  // if K1 and K2 are a one-bit mask.
+  ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
+  ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
+
+  if (LHS->getPredicate() == ICmpInst::ICMP_EQ && LHSCst && LHSCst->isZero() &&
+      RHS->getPredicate() == ICmpInst::ICMP_EQ && RHSCst && RHSCst->isZero()) {
+
+    BinaryOperator *LAnd = dyn_cast<BinaryOperator>(LHS->getOperand(0));
+    BinaryOperator *RAnd = dyn_cast<BinaryOperator>(RHS->getOperand(0));
+    if (LAnd && RAnd && LAnd->hasOneUse() && RHS->hasOneUse() &&
+        LAnd->getOpcode() == Instruction::And &&
+        RAnd->getOpcode() == Instruction::And) {
+
+      Value *Mask = 0;
+      Value *Masked = 0;
+      if (LAnd->getOperand(0) == RAnd->getOperand(0) &&
+          IsOneHotValue(LAnd->getOperand(1)) &&
+          IsOneHotValue(RAnd->getOperand(1))) {
+        Mask = Builder->CreateOr(LAnd->getOperand(1), RAnd->getOperand(1));
+        Masked = Builder->CreateAnd(LAnd->getOperand(0), Mask);
+      } else if (LAnd->getOperand(1) == RAnd->getOperand(1) &&
+                 IsOneHotValue(LAnd->getOperand(0)) &&
+                 IsOneHotValue(RAnd->getOperand(0))) {
+        Mask = Builder->CreateOr(LAnd->getOperand(0), RAnd->getOperand(0));
+        Masked = Builder->CreateAnd(LAnd->getOperand(1), Mask);
+      }
+
+      if (Masked)
+        return Builder->CreateICmp(ICmpInst::ICMP_NE, Masked, Mask);
+    }
+  }
+
   // (icmp1 A, B) | (icmp2 A, B) --> (icmp3 A, B)
   if (PredicatesFoldable(LHSCC, RHSCC)) {
     if (LHS->getOperand(0) == RHS->getOperand(1) &&
@@ -1477,13 +1613,37 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
 
   // handle (roughly):
   // (icmp ne (A & B), C) | (icmp ne (A & D), E)
-  if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, ICmpInst::ICMP_NE, Builder))
+  if (Value *V = foldLogOpOfMaskedICmps(LHS, RHS, false, Builder))
     return V;
 
-  // This only handles icmp of constants: (icmp1 A, C1) | (icmp2 B, C2).
   Value *Val = LHS->getOperand(0), *Val2 = RHS->getOperand(0);
-  ConstantInt *LHSCst = dyn_cast<ConstantInt>(LHS->getOperand(1));
-  ConstantInt *RHSCst = dyn_cast<ConstantInt>(RHS->getOperand(1));
+  if (LHS->hasOneUse() || RHS->hasOneUse()) {
+    // (icmp eq B, 0) | (icmp ult A, B) -> (icmp ule A, B-1)
+    // (icmp eq B, 0) | (icmp ugt B, A) -> (icmp ule A, B-1)
+    Value *A = 0, *B = 0;
+    if (LHSCC == ICmpInst::ICMP_EQ && LHSCst && LHSCst->isZero()) {
+      B = Val;
+      if (RHSCC == ICmpInst::ICMP_ULT && Val == RHS->getOperand(1))
+        A = Val2;
+      else if (RHSCC == ICmpInst::ICMP_UGT && Val == Val2)
+        A = RHS->getOperand(1);
+    }
+    // (icmp ult A, B) | (icmp eq B, 0) -> (icmp ule A, B-1)
+    // (icmp ugt B, A) | (icmp eq B, 0) -> (icmp ule A, B-1)
+    else if (RHSCC == ICmpInst::ICMP_EQ && RHSCst && RHSCst->isZero()) {
+      B = Val2;
+      if (LHSCC == ICmpInst::ICMP_ULT && Val2 == LHS->getOperand(1))
+        A = Val;
+      else if (LHSCC == ICmpInst::ICMP_UGT && Val2 == Val)
+        A = LHS->getOperand(1);
+    }
+    if (A && B)
+      return Builder->CreateICmp(
+          ICmpInst::ICMP_UGE,
+          Builder->CreateAdd(B, ConstantInt::getSigned(B->getType(), -1)), A);
+  }
+
+  // This only handles icmp of constants: (icmp1 A, C1) | (icmp2 B, C2).
   if (LHSCst == 0 || RHSCst == 0) return 0;
 
   if (LHSCst == RHSCst && LHSCC == RHSCC) {
@@ -1588,7 +1748,7 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
     case ICmpInst::ICMP_NE:          // (X != 13 | X != 15) -> true
     case ICmpInst::ICMP_ULT:         // (X != 13 | X u< 15) -> true
     case ICmpInst::ICMP_SLT:         // (X != 13 | X s< 15) -> true
-      return ConstantInt::getTrue(LHS->getContext());
+      return Builder->getTrue();
     }
   case ICmpInst::ICMP_ULT:
     switch (RHSCC) {
@@ -1640,7 +1800,7 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
       break;
     case ICmpInst::ICMP_NE:         // (X u> 13 | X != 15) -> true
     case ICmpInst::ICMP_ULT:        // (X u> 13 | X u< 15) -> true
-      return ConstantInt::getTrue(LHS->getContext());
+      return Builder->getTrue();
     case ICmpInst::ICMP_SLT:        // (X u> 13 | X s< 15) -> no change
       break;
     }
@@ -1655,7 +1815,7 @@ Value *InstCombiner::FoldOrOfICmps(ICmpInst *LHS, ICmpInst *RHS) {
       break;
     case ICmpInst::ICMP_NE:         // (X s> 13 | X != 15) -> true
     case ICmpInst::ICMP_SLT:        // (X s> 13 | X s< 15) -> true
-      return ConstantInt::getTrue(LHS->getContext());
+      return Builder->getTrue();
     case ICmpInst::ICMP_ULT:        // (X s> 13 | X u< 15) -> no change
       break;
     }
@@ -1676,7 +1836,7 @@ Value *InstCombiner::FoldOrOfFCmps(FCmpInst *LHS, FCmpInst *RHS) {
         // If either of the constants are nans, then the whole thing returns
         // true.
         if (LHSC->getValueAPF().isNaN() || RHSC->getValueAPF().isNaN())
-          return ConstantInt::getTrue(LHS->getContext());
+          return Builder->getTrue();
 
         // Otherwise, no need to compare the two constants, compare the
         // rest.
@@ -1779,8 +1939,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
       Value *Or = Builder->CreateOr(X, RHS);
       Or->takeName(Op0);
       return BinaryOperator::CreateAnd(Or,
-                         ConstantInt::get(I.getContext(),
-                                          RHS->getValue() | C1->getValue()));
+                             Builder->getInt(RHS->getValue() | C1->getValue()));
     }
 
     // (X ^ C1) | C2 --> (X | C2) ^ (C1&~C2)
@@ -1789,8 +1948,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
       Value *Or = Builder->CreateOr(X, RHS);
       Or->takeName(Op0);
       return BinaryOperator::CreateXor(Or,
-                 ConstantInt::get(I.getContext(),
-                                  C1->getValue() & ~RHS->getValue()));
+                            Builder->getInt(C1->getValue() & ~RHS->getValue()));
     }
 
     // Try to fold constant and into select arguments.
@@ -1872,15 +2030,13 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
             ((V1 == B && MaskedValueIsZero(V2, ~C1->getValue())) ||  // (V|N)
              (V2 == B && MaskedValueIsZero(V1, ~C1->getValue()))))   // (N|V)
           return BinaryOperator::CreateAnd(A,
-                               ConstantInt::get(A->getContext(),
-                                                C1->getValue()|C2->getValue()));
+                                Builder->getInt(C1->getValue()|C2->getValue()));
         // Or commutes, try both ways.
         if (match(B, m_Or(m_Value(V1), m_Value(V2))) &&
             ((V1 == A && MaskedValueIsZero(V2, ~C2->getValue())) ||  // (V|N)
              (V2 == A && MaskedValueIsZero(V1, ~C2->getValue()))))   // (N|V)
           return BinaryOperator::CreateAnd(B,
-                               ConstantInt::get(B->getContext(),
-                                                C1->getValue()|C2->getValue()));
+                                Builder->getInt(C1->getValue()|C2->getValue()));
 
         // ((V|C3)&C1) | ((V|C4)&C2) --> (V|C3|C4)&(C1|C2)
         // iff (C1&C2) == 0 and (C3&~C1) == 0 and (C4&~C2) == 0.
@@ -1891,8 +2047,7 @@ Instruction *InstCombiner::visitOr(BinaryOperator &I) {
             (C4->getValue() & ~C2->getValue()) == 0) {
           V2 = Builder->CreateOr(V1, ConstantExpr::getOr(C3, C4), "bitfield");
           return BinaryOperator::CreateAnd(V2,
-                               ConstantInt::get(B->getContext(),
-                                                C1->getValue()|C2->getValue()));
+                                Builder->getInt(C1->getValue()|C2->getValue()));
         }
       }
     }
@@ -2160,8 +2315,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) {
         if (CI->hasOneUse() && Op0C->hasOneUse()) {
           Instruction::CastOps Opcode = Op0C->getOpcode();
           if ((Opcode == Instruction::ZExt || Opcode == Instruction::SExt) &&
-              (RHS == ConstantExpr::getCast(Opcode,
-                                           ConstantInt::getTrue(I.getContext()),
+              (RHS == ConstantExpr::getCast(Opcode, Builder->getTrue(),
                                             Op0C->getDestTy()))) {
             CI->setPredicate(CI->getInversePredicate());
             return CastInst::Create(Opcode, CI, Op0C->getType());
@@ -2191,8 +2345,7 @@ Instruction *InstCombiner::visitXor(BinaryOperator &I) {
                                       Op0I->getOperand(0));
           } else if (RHS->getValue().isSignBit()) {
             // (X + C) ^ signbit -> (X + C + signbit)
-            Constant *C = ConstantInt::get(I.getContext(),
-                                           RHS->getValue() + Op0CI->getValue());
+            Constant *C = Builder->getInt(RHS->getValue() + Op0CI->getValue());
             return BinaryOperator::CreateAdd(Op0I->getOperand(0), C);
 
           }