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

1 files changed, 217 insertions, 264 deletions

diff --git a/contrib/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp b/contrib/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
index 2d34c1c..809471c 100644
--- a/contrib/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
+++ b/contrib/llvm/lib/Transforms/InstCombine/InstCombineAddSub.cpp
@@ -17,6 +17,7 @@
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/GetElementPtrTypeIterator.h"
 #include "llvm/IR/PatternMatch.h"
+#include "llvm/Support/KnownBits.h"
 
 using namespace llvm;
 using namespace PatternMatch;
@@ -163,7 +164,7 @@ namespace {
   ///
   class FAddCombine {
   public:
-    FAddCombine(InstCombiner::BuilderTy *B) : Builder(B), Instr(nullptr) {}
+    FAddCombine(InstCombiner::BuilderTy &B) : Builder(B), Instr(nullptr) {}
     Value *simplify(Instruction *FAdd);
 
   private:
@@ -186,7 +187,7 @@ namespace {
     Value *createNaryFAdd(const AddendVect& Opnds, unsigned InstrQuota);
     void createInstPostProc(Instruction *NewInst, bool NoNumber = false);
 
-    InstCombiner::BuilderTy *Builder;
+    InstCombiner::BuilderTy &Builder;
     Instruction *Instr;
 
      // Debugging stuff are clustered here.
@@ -734,7 +735,7 @@ Value *FAddCombine::createNaryFAdd
 }
 
 Value *FAddCombine::createFSub(Value *Opnd0, Value *Opnd1) {
-  Value *V = Builder->CreateFSub(Opnd0, Opnd1);
+  Value *V = Builder.CreateFSub(Opnd0, Opnd1);
   if (Instruction *I = dyn_cast<Instruction>(V))
     createInstPostProc(I);
   return V;
@@ -749,21 +750,21 @@ Value *FAddCombine::createFNeg(Value *V) {
 }
 
 Value *FAddCombine::createFAdd(Value *Opnd0, Value *Opnd1) {
-  Value *V = Builder->CreateFAdd(Opnd0, Opnd1);
+  Value *V = Builder.CreateFAdd(Opnd0, Opnd1);
   if (Instruction *I = dyn_cast<Instruction>(V))
     createInstPostProc(I);
   return V;
 }
 
 Value *FAddCombine::createFMul(Value *Opnd0, Value *Opnd1) {
-  Value *V = Builder->CreateFMul(Opnd0, Opnd1);
+  Value *V = Builder.CreateFMul(Opnd0, Opnd1);
   if (Instruction *I = dyn_cast<Instruction>(V))
     createInstPostProc(I);
   return V;
 }
 
 Value *FAddCombine::createFDiv(Value *Opnd0, Value *Opnd1) {
-  Value *V = Builder->CreateFDiv(Opnd0, Opnd1);
+  Value *V = Builder.CreateFDiv(Opnd0, Opnd1);
   if (Instruction *I = dyn_cast<Instruction>(V))
     createInstPostProc(I);
   return V;
@@ -794,6 +795,11 @@ unsigned FAddCombine::calcInstrNumber(const AddendVect &Opnds) {
     if (Opnd->isConstant())
       continue;
 
+    // The constant check above is really for a few special constant
+    // coefficients.
+    if (isa<UndefValue>(Opnd->getSymVal()))
+      continue;
+
     const FAddendCoef &CE = Opnd->getCoef();
     if (CE.isMinusOne() || CE.isMinusTwo())
       NegOpndNum++;
@@ -841,108 +847,28 @@ Value *FAddCombine::createAddendVal(const FAddend &Opnd, bool &NeedNeg) {
   return createFMul(OpndVal, Coeff.getValue(Instr->getType()));
 }
 
-// If one of the operands only has one non-zero bit, and if the other
-// operand has a known-zero bit in a more significant place than it (not
-// including the sign bit) the ripple may go up to and fill the zero, but
-// won't change the sign. For example, (X & ~4) + 1.
-static bool checkRippleForAdd(const APInt &Op0KnownZero,
-                              const APInt &Op1KnownZero) {
-  APInt Op1MaybeOne = ~Op1KnownZero;
-  // Make sure that one of the operand has at most one bit set to 1.
-  if (Op1MaybeOne.countPopulation() != 1)
-    return false;
-
-  // Find the most significant known 0 other than the sign bit.
-  int BitWidth = Op0KnownZero.getBitWidth();
-  APInt Op0KnownZeroTemp(Op0KnownZero);
-  Op0KnownZeroTemp.clearBit(BitWidth - 1);
-  int Op0ZeroPosition = BitWidth - Op0KnownZeroTemp.countLeadingZeros() - 1;
-
-  int Op1OnePosition = BitWidth - Op1MaybeOne.countLeadingZeros() - 1;
-  assert(Op1OnePosition >= 0);
-
-  // This also covers the case of no known zero, since in that case
-  // Op0ZeroPosition is -1.
-  return Op0ZeroPosition >= Op1OnePosition;
-}
-
-/// Return true if we can prove that:
-///    (sext (add LHS, RHS))  === (add (sext LHS), (sext RHS))
-/// This basically requires proving that the add in the original type would not
-/// overflow to change the sign bit or have a carry out.
-bool InstCombiner::WillNotOverflowSignedAdd(Value *LHS, Value *RHS,
-                                            Instruction &CxtI) {
-  // There are different heuristics we can use for this.  Here are some simple
-  // ones.
-
-  // If LHS and RHS each have at least two sign bits, the addition will look
-  // like
-  //
-  // XX..... +
-  // YY.....
-  //
-  // If the carry into the most significant position is 0, X and Y can't both
-  // be 1 and therefore the carry out of the addition is also 0.
-  //
-  // If the carry into the most significant position is 1, X and Y can't both
-  // be 0 and therefore the carry out of the addition is also 1.
-  //
-  // Since the carry into the most significant position is always equal to
-  // the carry out of the addition, there is no signed overflow.
-  if (ComputeNumSignBits(LHS, 0, &CxtI) > 1 &&
-      ComputeNumSignBits(RHS, 0, &CxtI) > 1)
-    return true;
-
-  unsigned BitWidth = LHS->getType()->getScalarSizeInBits();
-  APInt LHSKnownZero(BitWidth, 0);
-  APInt LHSKnownOne(BitWidth, 0);
-  computeKnownBits(LHS, LHSKnownZero, LHSKnownOne, 0, &CxtI);
-
-  APInt RHSKnownZero(BitWidth, 0);
-  APInt RHSKnownOne(BitWidth, 0);
-  computeKnownBits(RHS, RHSKnownZero, RHSKnownOne, 0, &CxtI);
-
-  // Addition of two 2's compliment numbers having opposite signs will never
-  // overflow.
-  if ((LHSKnownOne[BitWidth - 1] && RHSKnownZero[BitWidth - 1]) ||
-      (LHSKnownZero[BitWidth - 1] && RHSKnownOne[BitWidth - 1]))
-    return true;
-
-  // Check if carry bit of addition will not cause overflow.
-  if (checkRippleForAdd(LHSKnownZero, RHSKnownZero))
-    return true;
-  if (checkRippleForAdd(RHSKnownZero, LHSKnownZero))
-    return true;
-
-  return false;
-}
-
 /// \brief Return true if we can prove that:
 ///    (sub LHS, RHS)  === (sub nsw LHS, RHS)
 /// This basically requires proving that the add in the original type would not
 /// overflow to change the sign bit or have a carry out.
 /// TODO: Handle this for Vectors.
-bool InstCombiner::WillNotOverflowSignedSub(Value *LHS, Value *RHS,
-                                            Instruction &CxtI) {
+bool InstCombiner::willNotOverflowSignedSub(const Value *LHS,
+                                            const Value *RHS,
+                                            const Instruction &CxtI) const {
   // If LHS and RHS each have at least two sign bits, the subtraction
   // cannot overflow.
   if (ComputeNumSignBits(LHS, 0, &CxtI) > 1 &&
       ComputeNumSignBits(RHS, 0, &CxtI) > 1)
     return true;
 
-  unsigned BitWidth = LHS->getType()->getScalarSizeInBits();
-  APInt LHSKnownZero(BitWidth, 0);
-  APInt LHSKnownOne(BitWidth, 0);
-  computeKnownBits(LHS, LHSKnownZero, LHSKnownOne, 0, &CxtI);
+  KnownBits LHSKnown = computeKnownBits(LHS, 0, &CxtI);
 
-  APInt RHSKnownZero(BitWidth, 0);
-  APInt RHSKnownOne(BitWidth, 0);
-  computeKnownBits(RHS, RHSKnownZero, RHSKnownOne, 0, &CxtI);
+  KnownBits RHSKnown = computeKnownBits(RHS, 0, &CxtI);
 
-  // Subtraction of two 2's compliment numbers having identical signs will
+  // Subtraction of two 2's complement numbers having identical signs will
   // never overflow.
-  if ((LHSKnownOne[BitWidth - 1] && RHSKnownOne[BitWidth - 1]) ||
-      (LHSKnownZero[BitWidth - 1] && RHSKnownZero[BitWidth - 1]))
+  if ((LHSKnown.isNegative() && RHSKnown.isNegative()) ||
+      (LHSKnown.isNonNegative() && RHSKnown.isNonNegative()))
     return true;
 
   // TODO: implement logic similar to checkRippleForAdd
@@ -951,16 +877,13 @@ bool InstCombiner::WillNotOverflowSignedSub(Value *LHS, Value *RHS,
 
 /// \brief Return true if we can prove that:
 ///    (sub LHS, RHS)  === (sub nuw LHS, RHS)
-bool InstCombiner::WillNotOverflowUnsignedSub(Value *LHS, Value *RHS,
-                                              Instruction &CxtI) {
+bool InstCombiner::willNotOverflowUnsignedSub(const Value *LHS,
+                                              const Value *RHS,
+                                              const Instruction &CxtI) const {
   // If the LHS is negative and the RHS is non-negative, no unsigned wrap.
-  bool LHSKnownNonNegative, LHSKnownNegative;
-  bool RHSKnownNonNegative, RHSKnownNegative;
-  ComputeSignBit(LHS, LHSKnownNonNegative, LHSKnownNegative, /*Depth=*/0,
-                 &CxtI);
-  ComputeSignBit(RHS, RHSKnownNonNegative, RHSKnownNegative, /*Depth=*/0,
-                 &CxtI);
-  if (LHSKnownNegative && RHSKnownNonNegative)
+  KnownBits LHSKnown = computeKnownBits(LHS, /*Depth=*/0, &CxtI);
+  KnownBits RHSKnown = computeKnownBits(RHS, /*Depth=*/0, &CxtI);
+  if (LHSKnown.isNegative() && RHSKnown.isNonNegative())
     return true;
 
   return false;
@@ -972,7 +895,7 @@ bool InstCombiner::WillNotOverflowUnsignedSub(Value *LHS, Value *RHS,
 //   ADD(XOR(AND(Z, C), C), 1) == NEG(OR(Z, ~C))
 //   XOR(AND(Z, C), (C + 1)) == NEG(OR(Z, ~C)) if C is even
 static Value *checkForNegativeOperand(BinaryOperator &I,
-                                      InstCombiner::BuilderTy *Builder) {
+                                      InstCombiner::BuilderTy &Builder) {
   Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
 
   // This function creates 2 instructions to replace ADD, we need at least one
@@ -996,13 +919,13 @@ static Value *checkForNegativeOperand(BinaryOperator &I,
       // X = XOR(Y, C1), Y = OR(Z, C2), C2 = NOT(C1) ==> X == NOT(AND(Z, C1))
       // ADD(ADD(X, 1), RHS) == ADD(X, ADD(RHS, 1)) == SUB(RHS, AND(Z, C1))
       if (match(Y, m_Or(m_Value(Z), m_APInt(C2))) && (*C2 == ~(*C1))) {
-        Value *NewAnd = Builder->CreateAnd(Z, *C1);
-        return Builder->CreateSub(RHS, NewAnd, "sub");
+        Value *NewAnd = Builder.CreateAnd(Z, *C1);
+        return Builder.CreateSub(RHS, NewAnd, "sub");
       } else if (match(Y, m_And(m_Value(Z), m_APInt(C2))) && (*C1 == *C2)) {
         // X = XOR(Y, C1), Y = AND(Z, C2), C2 == C1 ==> X == NOT(OR(Z, ~C1))
         // ADD(ADD(X, 1), RHS) == ADD(X, ADD(RHS, 1)) == SUB(RHS, OR(Z, ~C1))
-        Value *NewOr = Builder->CreateOr(Z, ~(*C1));
-        return Builder->CreateSub(RHS, NewOr, "sub");
+        Value *NewOr = Builder.CreateOr(Z, ~(*C1));
+        return Builder.CreateSub(RHS, NewOr, "sub");
       }
     }
   }
@@ -1021,12 +944,73 @@ static Value *checkForNegativeOperand(BinaryOperator &I,
   if (match(LHS, m_Xor(m_Value(Y), m_APInt(C1))))
     if (C1->countTrailingZeros() == 0)
       if (match(Y, m_And(m_Value(Z), m_APInt(C2))) && *C1 == (*C2 + 1)) {
-        Value *NewOr = Builder->CreateOr(Z, ~(*C2));
-        return Builder->CreateSub(RHS, NewOr, "sub");
+        Value *NewOr = Builder.CreateOr(Z, ~(*C2));
+        return Builder.CreateSub(RHS, NewOr, "sub");
       }
   return nullptr;
 }
 
+static Instruction *foldAddWithConstant(BinaryOperator &Add,
+                                        InstCombiner::BuilderTy &Builder) {
+  Value *Op0 = Add.getOperand(0), *Op1 = Add.getOperand(1);
+  const APInt *C;
+  if (!match(Op1, m_APInt(C)))
+    return nullptr;
+
+  if (C->isSignMask()) {
+    // If wrapping is not allowed, then the addition must set the sign bit:
+    // X + (signmask) --> X | signmask
+    if (Add.hasNoSignedWrap() || Add.hasNoUnsignedWrap())
+      return BinaryOperator::CreateOr(Op0, Op1);
+
+    // If wrapping is allowed, then the addition flips the sign bit of LHS:
+    // X + (signmask) --> X ^ signmask
+    return BinaryOperator::CreateXor(Op0, Op1);
+  }
+
+  Value *X;
+  const APInt *C2;
+  Type *Ty = Add.getType();
+
+  // Is this add the last step in a convoluted sext?
+  // add(zext(xor i16 X, -32768), -32768) --> sext X
+  if (match(Op0, m_ZExt(m_Xor(m_Value(X), m_APInt(C2)))) &&
+      C2->isMinSignedValue() && C2->sext(Ty->getScalarSizeInBits()) == *C)
+    return CastInst::Create(Instruction::SExt, X, Ty);
+
+  // (add (zext (add nuw X, C2)), C) --> (zext (add nuw X, C2 + C))
+  // FIXME: This should check hasOneUse to not increase the instruction count?
+  if (C->isNegative() &&
+      match(Op0, m_ZExt(m_NUWAdd(m_Value(X), m_APInt(C2)))) &&
+      C->sge(-C2->sext(C->getBitWidth()))) {
+    Constant *NewC =
+        ConstantInt::get(X->getType(), *C2 + C->trunc(C2->getBitWidth()));
+    return new ZExtInst(Builder.CreateNUWAdd(X, NewC), Ty);
+  }
+
+  if (C->isOneValue() && Op0->hasOneUse()) {
+    // add (sext i1 X), 1 --> zext (not X)
+    // TODO: The smallest IR representation is (select X, 0, 1), and that would
+    // not require the one-use check. But we need to remove a transform in
+    // visitSelect and make sure that IR value tracking for select is equal or
+    // better than for these ops.
+    if (match(Op0, m_SExt(m_Value(X))) &&
+        X->getType()->getScalarSizeInBits() == 1)
+      return new ZExtInst(Builder.CreateNot(X), Ty);
+
+    // Shifts and add used to flip and mask off the low bit:
+    // add (ashr (shl i32 X, 31), 31), 1 --> and (not X), 1
+    const APInt *C3;
+    if (match(Op0, m_AShr(m_Shl(m_Value(X), m_APInt(C2)), m_APInt(C3))) &&
+        C2 == C3 && *C2 == Ty->getScalarSizeInBits() - 1) {
+      Value *NotX = Builder.CreateNot(X);
+      return BinaryOperator::CreateAnd(NotX, ConstantInt::get(Ty, 1));
+    }
+  }
+
+  return nullptr;
+}
+
 Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
   bool Changed = SimplifyAssociativeOrCommutative(I);
   Value *LHS = I.getOperand(0), *RHS = I.getOperand(1);
@@ -1034,51 +1018,21 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
   if (Value *V = SimplifyVectorOp(I))
     return replaceInstUsesWith(I, V);
 
-  if (Value *V = SimplifyAddInst(LHS, RHS, I.hasNoSignedWrap(),
-                                 I.hasNoUnsignedWrap(), DL, &TLI, &DT, &AC))
+  if (Value *V =
+          SimplifyAddInst(LHS, RHS, I.hasNoSignedWrap(), I.hasNoUnsignedWrap(),
+                          SQ.getWithInstruction(&I)))
     return replaceInstUsesWith(I, V);
 
    // (A*B)+(A*C) -> A*(B+C) etc
   if (Value *V = SimplifyUsingDistributiveLaws(I))
     return replaceInstUsesWith(I, V);
 
-  const APInt *Val;
-  if (match(RHS, m_APInt(Val))) {
-    // X + (signbit) --> X ^ signbit
-    if (Val->isSignBit())
-      return BinaryOperator::CreateXor(LHS, RHS);
-
-    // Is this add the last step in a convoluted sext?
-    Value *X;
-    const APInt *C;
-    if (match(LHS, m_ZExt(m_Xor(m_Value(X), m_APInt(C)))) &&
-        C->isMinSignedValue() &&
-        C->sext(LHS->getType()->getScalarSizeInBits()) == *Val) {
-      // add(zext(xor i16 X, -32768), -32768) --> sext X
-      return CastInst::Create(Instruction::SExt, X, LHS->getType());
-    }
-
-    if (Val->isNegative() &&
-        match(LHS, m_ZExt(m_NUWAdd(m_Value(X), m_APInt(C)))) &&
-        Val->sge(-C->sext(Val->getBitWidth()))) {
-      // (add (zext (add nuw X, C)), Val) -> (zext (add nuw X, C+Val))
-      return CastInst::Create(
-          Instruction::ZExt,
-          Builder->CreateNUWAdd(
-              X, Constant::getIntegerValue(X->getType(),
-                                           *C + Val->trunc(C->getBitWidth()))),
-          I.getType());
-    }
-  }
+  if (Instruction *X = foldAddWithConstant(I, Builder))
+    return X;
 
-  // FIXME: Use the match above instead of dyn_cast to allow these transforms
-  // for splat vectors.
+  // FIXME: This should be moved into the above helper function to allow these
+  // transforms for splat vectors.
   if (ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) {
-    // See if SimplifyDemandedBits can simplify this.  This handles stuff like
-    // (X & 254)+1 -> (X&254)|1
-    if (SimplifyDemandedInstructionBits(I))
-      return &I;
-
     // zext(bool) + C -> bool ? C + 1 : C
     if (ZExtInst *ZI = dyn_cast<ZExtInst>(LHS))
       if (ZI->getSrcTy()->isIntegerTy(1))
@@ -1106,34 +1060,31 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
 
       if (ExtendAmt) {
         Constant *ShAmt = ConstantInt::get(I.getType(), ExtendAmt);
-        Value *NewShl = Builder->CreateShl(XorLHS, ShAmt, "sext");
+        Value *NewShl = Builder.CreateShl(XorLHS, ShAmt, "sext");
         return BinaryOperator::CreateAShr(NewShl, ShAmt);
       }
 
       // If this is a xor that was canonicalized from a sub, turn it back into
       // a sub and fuse this add with it.
       if (LHS->hasOneUse() && (XorRHS->getValue()+1).isPowerOf2()) {
-        IntegerType *IT = cast<IntegerType>(I.getType());
-        APInt LHSKnownOne(IT->getBitWidth(), 0);
-        APInt LHSKnownZero(IT->getBitWidth(), 0);
-        computeKnownBits(XorLHS, LHSKnownZero, LHSKnownOne, 0, &I);
-        if ((XorRHS->getValue() | LHSKnownZero).isAllOnesValue())
+        KnownBits LHSKnown = computeKnownBits(XorLHS, 0, &I);
+        if ((XorRHS->getValue() | LHSKnown.Zero).isAllOnesValue())
           return BinaryOperator::CreateSub(ConstantExpr::getAdd(XorRHS, CI),
                                            XorLHS);
       }
-      // (X + signbit) + C could have gotten canonicalized to (X ^ signbit) + C,
-      // transform them into (X + (signbit ^ C))
-      if (XorRHS->getValue().isSignBit())
+      // (X + signmask) + C could have gotten canonicalized to (X^signmask) + C,
+      // transform them into (X + (signmask ^ C))
+      if (XorRHS->getValue().isSignMask())
         return BinaryOperator::CreateAdd(XorLHS,
                                          ConstantExpr::getXor(XorRHS, CI));
     }
   }
 
-  if (isa<Constant>(RHS) && isa<PHINode>(LHS))
-    if (Instruction *NV = FoldOpIntoPhi(I))
+  if (isa<Constant>(RHS))
+    if (Instruction *NV = foldOpWithConstantIntoOperand(I))
       return NV;
 
-  if (I.getType()->getScalarType()->isIntegerTy(1))
+  if (I.getType()->isIntOrIntVectorTy(1))
     return BinaryOperator::CreateXor(LHS, RHS);
 
   // X + X --> X << 1
@@ -1150,7 +1101,7 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
   if (Value *LHSV = dyn_castNegVal(LHS)) {
     if (!isa<Constant>(RHS))
       if (Value *RHSV = dyn_castNegVal(RHS)) {
-        Value *NewAdd = Builder->CreateAdd(LHSV, RHSV, "sum");
+        Value *NewAdd = Builder.CreateAdd(LHSV, RHSV, "sum");
         return BinaryOperator::CreateNeg(NewAdd);
       }
 
@@ -1197,15 +1148,10 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
 
       if (AddRHSHighBits == AddRHSHighBitsAnd) {
         // Okay, the xform is safe.  Insert the new add pronto.
-        Value *NewAdd = Builder->CreateAdd(X, CRHS, LHS->getName());
+        Value *NewAdd = Builder.CreateAdd(X, CRHS, LHS->getName());
         return BinaryOperator::CreateAnd(NewAdd, C2);
       }
     }
-
-    // Try to fold constant add into select arguments.
-    if (SelectInst *SI = dyn_cast<SelectInst>(LHS))
-      if (Instruction *R = FoldOpIntoSelect(I, SI))
-        return R;
   }
 
   // add (select X 0 (sub n A)) A  -->  select X A n
@@ -1242,10 +1188,10 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
         Constant *CI =
             ConstantExpr::getTrunc(RHSC, LHSConv->getOperand(0)->getType());
         if (ConstantExpr::getSExt(CI, I.getType()) == RHSC &&
-            WillNotOverflowSignedAdd(LHSConv->getOperand(0), CI, I)) {
+            willNotOverflowSignedAdd(LHSConv->getOperand(0), CI, I)) {
           // Insert the new, smaller add.
           Value *NewAdd =
-              Builder->CreateNSWAdd(LHSConv->getOperand(0), CI, "addconv");
+              Builder.CreateNSWAdd(LHSConv->getOperand(0), CI, "addconv");
           return new SExtInst(NewAdd, I.getType());
         }
       }
@@ -1253,16 +1199,16 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
 
     // (add (sext x), (sext y)) --> (sext (add int x, y))
     if (SExtInst *RHSConv = dyn_cast<SExtInst>(RHS)) {
-      // Only do this if x/y have the same type, if at last one of them has a
+      // Only do this if x/y have the same type, if at least one of them has a
       // single use (so we don't increase the number of sexts), and if the
       // integer add will not overflow.
       if (LHSConv->getOperand(0)->getType() ==
               RHSConv->getOperand(0)->getType() &&
           (LHSConv->hasOneUse() || RHSConv->hasOneUse()) &&
-          WillNotOverflowSignedAdd(LHSConv->getOperand(0),
+          willNotOverflowSignedAdd(LHSConv->getOperand(0),
                                    RHSConv->getOperand(0), I)) {
         // Insert the new integer add.
-        Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
+        Value *NewAdd = Builder.CreateNSWAdd(LHSConv->getOperand(0),
                                              RHSConv->getOperand(0), "addconv");
         return new SExtInst(NewAdd, I.getType());
       }
@@ -1278,11 +1224,10 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
         Constant *CI =
             ConstantExpr::getTrunc(RHSC, LHSConv->getOperand(0)->getType());
         if (ConstantExpr::getZExt(CI, I.getType()) == RHSC &&
-            computeOverflowForUnsignedAdd(LHSConv->getOperand(0), CI, &I) ==
-                OverflowResult::NeverOverflows) {
+            willNotOverflowUnsignedAdd(LHSConv->getOperand(0), CI, I)) {
           // Insert the new, smaller add.
           Value *NewAdd =
-              Builder->CreateNUWAdd(LHSConv->getOperand(0), CI, "addconv");
+              Builder.CreateNUWAdd(LHSConv->getOperand(0), CI, "addconv");
           return new ZExtInst(NewAdd, I.getType());
         }
       }
@@ -1290,17 +1235,16 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
 
     // (add (zext x), (zext y)) --> (zext (add int x, y))
     if (auto *RHSConv = dyn_cast<ZExtInst>(RHS)) {
-      // Only do this if x/y have the same type, if at last one of them has a
+      // Only do this if x/y have the same type, if at least one of them has a
       // single use (so we don't increase the number of zexts), and if the
       // integer add will not overflow.
       if (LHSConv->getOperand(0)->getType() ==
               RHSConv->getOperand(0)->getType() &&
           (LHSConv->hasOneUse() || RHSConv->hasOneUse()) &&
-          computeOverflowForUnsignedAdd(LHSConv->getOperand(0),
-                                        RHSConv->getOperand(0),
-                                        &I) == OverflowResult::NeverOverflows) {
+          willNotOverflowUnsignedAdd(LHSConv->getOperand(0),
+                                     RHSConv->getOperand(0), I)) {
         // Insert the new integer add.
-        Value *NewAdd = Builder->CreateNUWAdd(
+        Value *NewAdd = Builder.CreateNUWAdd(
             LHSConv->getOperand(0), RHSConv->getOperand(0), "addconv");
         return new ZExtInst(NewAdd, I.getType());
       }
@@ -1311,13 +1255,11 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
   {
     Value *A = nullptr, *B = nullptr;
     if (match(RHS, m_Xor(m_Value(A), m_Value(B))) &&
-        (match(LHS, m_And(m_Specific(A), m_Specific(B))) ||
-         match(LHS, m_And(m_Specific(B), m_Specific(A)))))
+        match(LHS, m_c_And(m_Specific(A), m_Specific(B))))
       return BinaryOperator::CreateOr(A, B);
 
     if (match(LHS, m_Xor(m_Value(A), m_Value(B))) &&
-        (match(RHS, m_And(m_Specific(A), m_Specific(B))) ||
-         match(RHS, m_And(m_Specific(B), m_Specific(A)))))
+        match(RHS, m_c_And(m_Specific(A), m_Specific(B))))
       return BinaryOperator::CreateOr(A, B);
   }
 
@@ -1325,8 +1267,7 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
   {
     Value *A = nullptr, *B = nullptr;
     if (match(RHS, m_Or(m_Value(A), m_Value(B))) &&
-        (match(LHS, m_And(m_Specific(A), m_Specific(B))) ||
-         match(LHS, m_And(m_Specific(B), m_Specific(A))))) {
+        match(LHS, m_c_And(m_Specific(A), m_Specific(B)))) {
       auto *New = BinaryOperator::CreateAdd(A, B);
       New->setHasNoSignedWrap(I.hasNoSignedWrap());
       New->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
@@ -1334,8 +1275,7 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
     }
 
     if (match(LHS, m_Or(m_Value(A), m_Value(B))) &&
-        (match(RHS, m_And(m_Specific(A), m_Specific(B))) ||
-         match(RHS, m_And(m_Specific(B), m_Specific(A))))) {
+        match(RHS, m_c_And(m_Specific(A), m_Specific(B)))) {
       auto *New = BinaryOperator::CreateAdd(A, B);
       New->setHasNoSignedWrap(I.hasNoSignedWrap());
       New->setHasNoUnsignedWrap(I.hasNoUnsignedWrap());
@@ -1343,16 +1283,14 @@ Instruction *InstCombiner::visitAdd(BinaryOperator &I) {
     }
   }
 
-  // TODO(jingyue): Consider WillNotOverflowSignedAdd and
-  // WillNotOverflowUnsignedAdd to reduce the number of invocations of
+  // TODO(jingyue): Consider willNotOverflowSignedAdd and
+  // willNotOverflowUnsignedAdd to reduce the number of invocations of
   // computeKnownBits.
-  if (!I.hasNoSignedWrap() && WillNotOverflowSignedAdd(LHS, RHS, I)) {
+  if (!I.hasNoSignedWrap() && willNotOverflowSignedAdd(LHS, RHS, I)) {
     Changed = true;
     I.setHasNoSignedWrap(true);
   }
-  if (!I.hasNoUnsignedWrap() &&
-      computeOverflowForUnsignedAdd(LHS, RHS, &I) ==
-          OverflowResult::NeverOverflows) {
+  if (!I.hasNoUnsignedWrap() && willNotOverflowUnsignedAdd(LHS, RHS, I)) {
     Changed = true;
     I.setHasNoUnsignedWrap(true);
   }
@@ -1367,8 +1305,8 @@ Instruction *InstCombiner::visitFAdd(BinaryOperator &I) {
   if (Value *V = SimplifyVectorOp(I))
     return replaceInstUsesWith(I, V);
 
-  if (Value *V =
-          SimplifyFAddInst(LHS, RHS, I.getFastMathFlags(), DL, &TLI, &DT, &AC))
+  if (Value *V = SimplifyFAddInst(LHS, RHS, I.getFastMathFlags(),
+                                  SQ.getWithInstruction(&I)))
     return replaceInstUsesWith(I, V);
 
   if (isa<Constant>(RHS))
@@ -1394,38 +1332,57 @@ Instruction *InstCombiner::visitFAdd(BinaryOperator &I) {
   // Check for (fadd double (sitofp x), y), see if we can merge this into an
   // integer add followed by a promotion.
   if (SIToFPInst *LHSConv = dyn_cast<SIToFPInst>(LHS)) {
+    Value *LHSIntVal = LHSConv->getOperand(0);
+    Type *FPType = LHSConv->getType();
+
+    // TODO: This check is overly conservative. In many cases known bits
+    // analysis can tell us that the result of the addition has less significant
+    // bits than the integer type can hold.
+    auto IsValidPromotion = [](Type *FTy, Type *ITy) {
+      Type *FScalarTy = FTy->getScalarType();
+      Type *IScalarTy = ITy->getScalarType();
+
+      // Do we have enough bits in the significand to represent the result of
+      // the integer addition?
+      unsigned MaxRepresentableBits =
+          APFloat::semanticsPrecision(FScalarTy->getFltSemantics());
+      return IScalarTy->getIntegerBitWidth() <= MaxRepresentableBits;
+    };
+
     // (fadd double (sitofp x), fpcst) --> (sitofp (add int x, intcst))
     // ... if the constant fits in the integer value.  This is useful for things
     // like (double)(x & 1234) + 4.0 -> (double)((X & 1234)+4) which no longer
     // requires a constant pool load, and generally allows the add to be better
     // instcombined.
-    if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHS)) {
-      Constant *CI =
-      ConstantExpr::getFPToSI(CFP, LHSConv->getOperand(0)->getType());
-      if (LHSConv->hasOneUse() &&
-          ConstantExpr::getSIToFP(CI, I.getType()) == CFP &&
-          WillNotOverflowSignedAdd(LHSConv->getOperand(0), CI, I)) {
-        // Insert the new integer add.
-        Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
-                                              CI, "addconv");
-        return new SIToFPInst(NewAdd, I.getType());
+    if (ConstantFP *CFP = dyn_cast<ConstantFP>(RHS))
+      if (IsValidPromotion(FPType, LHSIntVal->getType())) {
+        Constant *CI =
+          ConstantExpr::getFPToSI(CFP, LHSIntVal->getType());
+        if (LHSConv->hasOneUse() &&
+            ConstantExpr::getSIToFP(CI, I.getType()) == CFP &&
+            willNotOverflowSignedAdd(LHSIntVal, CI, I)) {
+          // Insert the new integer add.
+          Value *NewAdd = Builder.CreateNSWAdd(LHSIntVal, CI, "addconv");
+          return new SIToFPInst(NewAdd, I.getType());
+        }
       }
-    }
 
     // (fadd double (sitofp x), (sitofp y)) --> (sitofp (add int x, y))
     if (SIToFPInst *RHSConv = dyn_cast<SIToFPInst>(RHS)) {
-      // Only do this if x/y have the same type, if at last one of them has a
-      // single use (so we don't increase the number of int->fp conversions),
-      // and if the integer add will not overflow.
-      if (LHSConv->getOperand(0)->getType() ==
-              RHSConv->getOperand(0)->getType() &&
-          (LHSConv->hasOneUse() || RHSConv->hasOneUse()) &&
-          WillNotOverflowSignedAdd(LHSConv->getOperand(0),
-                                   RHSConv->getOperand(0), I)) {
-        // Insert the new integer add.
-        Value *NewAdd = Builder->CreateNSWAdd(LHSConv->getOperand(0),
-                                              RHSConv->getOperand(0),"addconv");
-        return new SIToFPInst(NewAdd, I.getType());
+      Value *RHSIntVal = RHSConv->getOperand(0);
+      // It's enough to check LHS types only because we require int types to
+      // be the same for this transform.
+      if (IsValidPromotion(FPType, LHSIntVal->getType())) {
+        // Only do this if x/y have the same type, if at least one of them has a
+        // single use (so we don't increase the number of int->fp conversions),
+        // and if the integer add will not overflow.
+        if (LHSIntVal->getType() == RHSIntVal->getType() &&
+            (LHSConv->hasOneUse() || RHSConv->hasOneUse()) &&
+            willNotOverflowSignedAdd(LHSIntVal, RHSIntVal, I)) {
+          // Insert the new integer add.
+          Value *NewAdd = Builder.CreateNSWAdd(LHSIntVal, RHSIntVal, "addconv");
+          return new SIToFPInst(NewAdd, I.getType());
+        }
       }
     }
   }
@@ -1521,14 +1478,14 @@ Value *InstCombiner::OptimizePointerDifference(Value *LHS, Value *RHS,
   // pointer, subtract it from the offset we have.
   if (GEP2) {
     Value *Offset = EmitGEPOffset(GEP2);
-    Result = Builder->CreateSub(Result, Offset);
+    Result = Builder.CreateSub(Result, Offset);
   }
 
   // If we have p - gep(p, ...)  then we have to negate the result.
   if (Swapped)
-    Result = Builder->CreateNeg(Result, "diff.neg");
+    Result = Builder.CreateNeg(Result, "diff.neg");
 
-  return Builder->CreateIntCast(Result, Ty, true);
+  return Builder.CreateIntCast(Result, Ty, true);
 }
 
 Instruction *InstCombiner::visitSub(BinaryOperator &I) {
@@ -1537,8 +1494,9 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
   if (Value *V = SimplifyVectorOp(I))
     return replaceInstUsesWith(I, V);
 
-  if (Value *V = SimplifySubInst(Op0, Op1, I.hasNoSignedWrap(),
-                                 I.hasNoUnsignedWrap(), DL, &TLI, &DT, &AC))
+  if (Value *V =
+          SimplifySubInst(Op0, Op1, I.hasNoSignedWrap(), I.hasNoUnsignedWrap(),
+                          SQ.getWithInstruction(&I)))
     return replaceInstUsesWith(I, V);
 
   // (A*B)-(A*C) -> A*(B-C) etc
@@ -1562,7 +1520,7 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
     return Res;
   }
 
-  if (I.getType()->isIntegerTy(1))
+  if (I.getType()->isIntOrIntVectorTy(1))
     return BinaryOperator::CreateXor(Op0, Op1);
 
   // Replace (-1 - A) with (~A).
@@ -1580,22 +1538,24 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
       if (Instruction *R = FoldOpIntoSelect(I, SI))
         return R;
 
+    // Try to fold constant sub into PHI values.
+    if (PHINode *PN = dyn_cast<PHINode>(Op1))
+      if (Instruction *R = foldOpIntoPhi(I, PN))
+        return R;
+
     // C-(X+C2) --> (C-C2)-X
     Constant *C2;
     if (match(Op1, m_Add(m_Value(X), m_Constant(C2))))
       return BinaryOperator::CreateSub(ConstantExpr::getSub(C, C2), X);
 
-    if (SimplifyDemandedInstructionBits(I))
-      return &I;
-
     // Fold (sub 0, (zext bool to B)) --> (sext bool to B)
     if (C->isNullValue() && match(Op1, m_ZExt(m_Value(X))))
-      if (X->getType()->getScalarType()->isIntegerTy(1))
+      if (X->getType()->isIntOrIntVectorTy(1))
         return CastInst::CreateSExtOrBitCast(X, Op1->getType());
 
     // Fold (sub 0, (sext bool to B)) --> (zext bool to B)
     if (C->isNullValue() && match(Op1, m_SExt(m_Value(X))))
-      if (X->getType()->getScalarType()->isIntegerTy(1))
+      if (X->getType()->isIntOrIntVectorTy(1))
         return CastInst::CreateZExtOrBitCast(X, Op1->getType());
   }
 
@@ -1605,7 +1565,7 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
 
     // -(X >>u 31) -> (X >>s 31)
     // -(X >>s 31) -> (X >>u 31)
-    if (*Op0C == 0) {
+    if (Op0C->isNullValue()) {
       Value *X;
       const APInt *ShAmt;
       if (match(Op1, m_LShr(m_Value(X), m_APInt(ShAmt))) &&
@@ -1622,11 +1582,9 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
 
     // Turn this into a xor if LHS is 2^n-1 and the remaining bits are known
     // zero.
-    if ((*Op0C + 1).isPowerOf2()) {
-      APInt KnownZero(BitWidth, 0);
-      APInt KnownOne(BitWidth, 0);
-      computeKnownBits(&I, KnownZero, KnownOne, 0, &I);
-      if ((*Op0C | KnownZero).isAllOnesValue())
+    if (Op0C->isMask()) {
+      KnownBits RHSKnown = computeKnownBits(Op1, 0, &I);
+      if ((*Op0C | RHSKnown.Zero).isAllOnesValue())
         return BinaryOperator::CreateXor(Op1, Op0);
     }
   }
@@ -1634,8 +1592,7 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
   {
     Value *Y;
     // X-(X+Y) == -Y    X-(Y+X) == -Y
-    if (match(Op1, m_Add(m_Specific(Op0), m_Value(Y))) ||
-        match(Op1, m_Add(m_Value(Y), m_Specific(Op0))))
+    if (match(Op1, m_c_Add(m_Specific(Op0), m_Value(Y))))
       return BinaryOperator::CreateNeg(Y);
 
     // (X-Y)-X == -Y
@@ -1645,38 +1602,34 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
 
   // (sub (or A, B) (xor A, B)) --> (and A, B)
   {
-    Value *A = nullptr, *B = nullptr;
+    Value *A, *B;
     if (match(Op1, m_Xor(m_Value(A), m_Value(B))) &&
-        (match(Op0, m_Or(m_Specific(A), m_Specific(B))) ||
-         match(Op0, m_Or(m_Specific(B), m_Specific(A)))))
+        match(Op0, m_c_Or(m_Specific(A), m_Specific(B))))
       return BinaryOperator::CreateAnd(A, B);
   }
 
-  if (Op0->hasOneUse()) {
-    Value *Y = nullptr;
+  {
+    Value *Y;
     // ((X | Y) - X) --> (~X & Y)
-    if (match(Op0, m_Or(m_Value(Y), m_Specific(Op1))) ||
-        match(Op0, m_Or(m_Specific(Op1), m_Value(Y))))
+    if (match(Op0, m_OneUse(m_c_Or(m_Value(Y), m_Specific(Op1)))))
       return BinaryOperator::CreateAnd(
-          Y, Builder->CreateNot(Op1, Op1->getName() + ".not"));
+          Y, Builder.CreateNot(Op1, Op1->getName() + ".not"));
   }
 
   if (Op1->hasOneUse()) {
     Value *X = nullptr, *Y = nullptr, *Z = nullptr;
     Constant *C = nullptr;
-    Constant *CI = nullptr;
 
     // (X - (Y - Z))  -->  (X + (Z - Y)).
     if (match(Op1, m_Sub(m_Value(Y), m_Value(Z))))
       return BinaryOperator::CreateAdd(Op0,
-                                      Builder->CreateSub(Z, Y, Op1->getName()));
+                                      Builder.CreateSub(Z, Y, Op1->getName()));
 
     // (X - (X & Y))   -->   (X & ~Y)
     //
-    if (match(Op1, m_And(m_Value(Y), m_Specific(Op0))) ||
-        match(Op1, m_And(m_Specific(Op0), m_Value(Y))))
+    if (match(Op1, m_c_And(m_Value(Y), m_Specific(Op0))))
       return BinaryOperator::CreateAnd(Op0,
-                                  Builder->CreateNot(Y, Y->getName() + ".not"));
+                                  Builder.CreateNot(Y, Y->getName() + ".not"));
 
     // 0 - (X sdiv C)  -> (X sdiv -C)  provided the negation doesn't overflow.
     if (match(Op1, m_SDiv(m_Value(X), m_Constant(C))) && match(Op0, m_Zero()) &&
@@ -1693,7 +1646,7 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
     // 'nuw' is dropped in favor of the canonical form.
     if (match(Op1, m_SExt(m_Value(Y))) &&
         Y->getType()->getScalarSizeInBits() == 1) {
-      Value *Zext = Builder->CreateZExt(Y, I.getType());
+      Value *Zext = Builder.CreateZExt(Y, I.getType());
       BinaryOperator *Add = BinaryOperator::CreateAdd(Op0, Zext);
       Add->setHasNoSignedWrap(I.hasNoSignedWrap());
       return Add;
@@ -1702,15 +1655,15 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
     // X - A*-B -> X + A*B
     // X - -A*B -> X + A*B
     Value *A, *B;
-    if (match(Op1, m_Mul(m_Value(A), m_Neg(m_Value(B)))) ||
-        match(Op1, m_Mul(m_Neg(m_Value(A)), m_Value(B))))
-      return BinaryOperator::CreateAdd(Op0, Builder->CreateMul(A, B));
+    Constant *CI;
+    if (match(Op1, m_c_Mul(m_Value(A), m_Neg(m_Value(B)))))
+      return BinaryOperator::CreateAdd(Op0, Builder.CreateMul(A, B));
 
     // X - A*CI -> X + A*-CI
-    // X - CI*A -> X + A*-CI
-    if (match(Op1, m_Mul(m_Value(A), m_Constant(CI))) ||
-        match(Op1, m_Mul(m_Constant(CI), m_Value(A)))) {
-      Value *NewMul = Builder->CreateMul(A, ConstantExpr::getNeg(CI));
+    // No need to handle commuted multiply because multiply handling will
+    // ensure constant will be move to the right hand side.
+    if (match(Op1, m_Mul(m_Value(A), m_Constant(CI)))) {
+      Value *NewMul = Builder.CreateMul(A, ConstantExpr::getNeg(CI));
       return BinaryOperator::CreateAdd(Op0, NewMul);
     }
   }
@@ -1730,11 +1683,11 @@ Instruction *InstCombiner::visitSub(BinaryOperator &I) {
       return replaceInstUsesWith(I, Res);
 
   bool Changed = false;
-  if (!I.hasNoSignedWrap() && WillNotOverflowSignedSub(Op0, Op1, I)) {
+  if (!I.hasNoSignedWrap() && willNotOverflowSignedSub(Op0, Op1, I)) {
     Changed = true;
     I.setHasNoSignedWrap(true);
   }
-  if (!I.hasNoUnsignedWrap() && WillNotOverflowUnsignedSub(Op0, Op1, I)) {
+  if (!I.hasNoUnsignedWrap() && willNotOverflowUnsignedSub(Op0, Op1, I)) {
     Changed = true;
     I.setHasNoUnsignedWrap(true);
   }
@@ -1748,8 +1701,8 @@ Instruction *InstCombiner::visitFSub(BinaryOperator &I) {
   if (Value *V = SimplifyVectorOp(I))
     return replaceInstUsesWith(I, V);
 
-  if (Value *V =
-          SimplifyFSubInst(Op0, Op1, I.getFastMathFlags(), DL, &TLI, &DT, &AC))
+  if (Value *V = SimplifyFSubInst(Op0, Op1, I.getFastMathFlags(),
+                                  SQ.getWithInstruction(&I)))
     return replaceInstUsesWith(I, V);
 
   // fsub nsz 0, X ==> fsub nsz -0.0, X
@@ -1774,14 +1727,14 @@ Instruction *InstCombiner::visitFSub(BinaryOperator &I) {
   }
   if (FPTruncInst *FPTI = dyn_cast<FPTruncInst>(Op1)) {
     if (Value *V = dyn_castFNegVal(FPTI->getOperand(0))) {
-      Value *NewTrunc = Builder->CreateFPTrunc(V, I.getType());
+      Value *NewTrunc = Builder.CreateFPTrunc(V, I.getType());
       Instruction *NewI = BinaryOperator::CreateFAdd(Op0, NewTrunc);
       NewI->copyFastMathFlags(&I);
       return NewI;
     }
   } else if (FPExtInst *FPEI = dyn_cast<FPExtInst>(Op1)) {
     if (Value *V = dyn_castFNegVal(FPEI->getOperand(0))) {
-      Value *NewExt = Builder->CreateFPExt(V, I.getType());
+      Value *NewExt = Builder.CreateFPExt(V, I.getType());
       Instruction *NewI = BinaryOperator::CreateFAdd(Op0, NewExt);
       NewI->copyFastMathFlags(&I);
       return NewI;