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, 249 insertions, 166 deletions

diff --git a/contrib/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp b/contrib/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
index e74b590..dfdfd3e 100644
--- a/contrib/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
+++ b/contrib/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
@@ -14,9 +14,10 @@
 #include "InstCombineInternal.h"
 #include "llvm/ADT/SetVector.h"
 #include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/TargetLibraryInfo.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/PatternMatch.h"
-#include "llvm/Analysis/TargetLibraryInfo.h"
+#include "llvm/Support/KnownBits.h"
 using namespace llvm;
 using namespace PatternMatch;
 
@@ -83,7 +84,7 @@ Instruction *InstCombiner::PromoteCastOfAllocation(BitCastInst &CI,
                                                    AllocaInst &AI) {
   PointerType *PTy = cast<PointerType>(CI.getType());
 
-  BuilderTy AllocaBuilder(*Builder);
+  BuilderTy AllocaBuilder(Builder);
   AllocaBuilder.SetInsertPoint(&AI);
 
   // Get the type really allocated and the type casted to.
@@ -274,12 +275,12 @@ Instruction *InstCombiner::commonCastTransforms(CastInst &CI) {
       return NV;
 
   // If we are casting a PHI, then fold the cast into the PHI.
-  if (isa<PHINode>(Src)) {
+  if (auto *PN = dyn_cast<PHINode>(Src)) {
     // Don't do this if it would create a PHI node with an illegal type from a
     // legal type.
     if (!Src->getType()->isIntegerTy() || !CI.getType()->isIntegerTy() ||
-        ShouldChangeType(CI.getType(), Src->getType()))
-      if (Instruction *NV = FoldOpIntoPhi(CI))
+        shouldChangeType(CI.getType(), Src->getType()))
+      if (Instruction *NV = foldOpIntoPhi(CI, PN))
         return NV;
   }
 
@@ -405,8 +406,7 @@ static bool canEvaluateTruncated(Value *V, Type *Ty, InstCombiner &IC,
 ///   trunc (lshr (bitcast <4 x i32> %X to i128), 32) to i32
 ///   --->
 ///   extractelement <4 x i32> %X, 1
-static Instruction *foldVecTruncToExtElt(TruncInst &Trunc, InstCombiner &IC,
-                                         const DataLayout &DL) {
+static Instruction *foldVecTruncToExtElt(TruncInst &Trunc, InstCombiner &IC) {
   Value *TruncOp = Trunc.getOperand(0);
   Type *DestType = Trunc.getType();
   if (!TruncOp->hasOneUse() || !isa<IntegerType>(DestType))
@@ -433,21 +433,21 @@ static Instruction *foldVecTruncToExtElt(TruncInst &Trunc, InstCombiner &IC,
   unsigned NumVecElts = VecWidth / DestWidth;
   if (VecType->getElementType() != DestType) {
     VecType = VectorType::get(DestType, NumVecElts);
-    VecInput = IC.Builder->CreateBitCast(VecInput, VecType, "bc");
+    VecInput = IC.Builder.CreateBitCast(VecInput, VecType, "bc");
   }
 
   unsigned Elt = ShiftAmount / DestWidth;
-  if (DL.isBigEndian())
+  if (IC.getDataLayout().isBigEndian())
     Elt = NumVecElts - 1 - Elt;
 
-  return ExtractElementInst::Create(VecInput, IC.Builder->getInt32(Elt));
+  return ExtractElementInst::Create(VecInput, IC.Builder.getInt32(Elt));
 }
 
 /// Try to narrow the width of bitwise logic instructions with constants.
 Instruction *InstCombiner::shrinkBitwiseLogic(TruncInst &Trunc) {
   Type *SrcTy = Trunc.getSrcTy();
   Type *DestTy = Trunc.getType();
-  if (isa<IntegerType>(SrcTy) && !ShouldChangeType(SrcTy, DestTy))
+  if (isa<IntegerType>(SrcTy) && !shouldChangeType(SrcTy, DestTy))
     return nullptr;
 
   BinaryOperator *LogicOp;
@@ -459,10 +459,60 @@ Instruction *InstCombiner::shrinkBitwiseLogic(TruncInst &Trunc) {
 
   // trunc (logic X, C) --> logic (trunc X, C')
   Constant *NarrowC = ConstantExpr::getTrunc(C, DestTy);
-  Value *NarrowOp0 = Builder->CreateTrunc(LogicOp->getOperand(0), DestTy);
+  Value *NarrowOp0 = Builder.CreateTrunc(LogicOp->getOperand(0), DestTy);
   return BinaryOperator::Create(LogicOp->getOpcode(), NarrowOp0, NarrowC);
 }
 
+/// Try to narrow the width of a splat shuffle. This could be generalized to any
+/// shuffle with a constant operand, but we limit the transform to avoid
+/// creating a shuffle type that targets may not be able to lower effectively.
+static Instruction *shrinkSplatShuffle(TruncInst &Trunc,
+                                       InstCombiner::BuilderTy &Builder) {
+  auto *Shuf = dyn_cast<ShuffleVectorInst>(Trunc.getOperand(0));
+  if (Shuf && Shuf->hasOneUse() && isa<UndefValue>(Shuf->getOperand(1)) &&
+      Shuf->getMask()->getSplatValue() &&
+      Shuf->getType() == Shuf->getOperand(0)->getType()) {
+    // trunc (shuf X, Undef, SplatMask) --> shuf (trunc X), Undef, SplatMask
+    Constant *NarrowUndef = UndefValue::get(Trunc.getType());
+    Value *NarrowOp = Builder.CreateTrunc(Shuf->getOperand(0), Trunc.getType());
+    return new ShuffleVectorInst(NarrowOp, NarrowUndef, Shuf->getMask());
+  }
+
+  return nullptr;
+}
+
+/// Try to narrow the width of an insert element. This could be generalized for
+/// any vector constant, but we limit the transform to insertion into undef to
+/// avoid potential backend problems from unsupported insertion widths. This
+/// could also be extended to handle the case of inserting a scalar constant
+/// into a vector variable.
+static Instruction *shrinkInsertElt(CastInst &Trunc,
+                                    InstCombiner::BuilderTy &Builder) {
+  Instruction::CastOps Opcode = Trunc.getOpcode();
+  assert((Opcode == Instruction::Trunc || Opcode == Instruction::FPTrunc) &&
+         "Unexpected instruction for shrinking");
+
+  auto *InsElt = dyn_cast<InsertElementInst>(Trunc.getOperand(0));
+  if (!InsElt || !InsElt->hasOneUse())
+    return nullptr;
+
+  Type *DestTy = Trunc.getType();
+  Type *DestScalarTy = DestTy->getScalarType();
+  Value *VecOp = InsElt->getOperand(0);
+  Value *ScalarOp = InsElt->getOperand(1);
+  Value *Index = InsElt->getOperand(2);
+
+  if (isa<UndefValue>(VecOp)) {
+    // trunc   (inselt undef, X, Index) --> inselt undef,   (trunc X), Index
+    // fptrunc (inselt undef, X, Index) --> inselt undef, (fptrunc X), Index
+    UndefValue *NarrowUndef = UndefValue::get(DestTy);
+    Value *NarrowOp = Builder.CreateCast(Opcode, ScalarOp, DestScalarTy);
+    return InsertElementInst::Create(NarrowUndef, NarrowOp, Index);
+  }
+
+  return nullptr;
+}
+
 Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
   if (Instruction *Result = commonCastTransforms(CI))
     return Result;
@@ -488,7 +538,7 @@ Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
   // type.   Only do this if the dest type is a simple type, don't convert the
   // expression tree to something weird like i93 unless the source is also
   // strange.
-  if ((DestTy->isVectorTy() || ShouldChangeType(SrcTy, DestTy)) &&
+  if ((DestTy->isVectorTy() || shouldChangeType(SrcTy, DestTy)) &&
       canEvaluateTruncated(Src, DestTy, *this, &CI)) {
 
     // If this cast is a truncate, evaluting in a different type always
@@ -503,11 +553,14 @@ Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
   // Canonicalize trunc x to i1 -> (icmp ne (and x, 1), 0), likewise for vector.
   if (DestTy->getScalarSizeInBits() == 1) {
     Constant *One = ConstantInt::get(SrcTy, 1);
-    Src = Builder->CreateAnd(Src, One);
+    Src = Builder.CreateAnd(Src, One);
     Value *Zero = Constant::getNullValue(Src->getType());
     return new ICmpInst(ICmpInst::ICMP_NE, Src, Zero);
   }
 
+  // FIXME: Maybe combine the next two transforms to handle the no cast case
+  // more efficiently. Support vector types. Cleanup code by using m_OneUse.
+
   // Transform trunc(lshr (zext A), Cst) to eliminate one type conversion.
   Value *A = nullptr; ConstantInt *Cst = nullptr;
   if (Src->hasOneUse() &&
@@ -526,36 +579,54 @@ Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
     // Since we're doing an lshr and a zero extend, and know that the shift
     // amount is smaller than ASize, it is always safe to do the shift in A's
     // type, then zero extend or truncate to the result.
-    Value *Shift = Builder->CreateLShr(A, Cst->getZExtValue());
+    Value *Shift = Builder.CreateLShr(A, Cst->getZExtValue());
     Shift->takeName(Src);
     return CastInst::CreateIntegerCast(Shift, DestTy, false);
   }
 
+  // FIXME: We should canonicalize to zext/trunc and remove this transform.
   // Transform trunc(lshr (sext A), Cst) to ashr A, Cst to eliminate type
   // conversion.
   // It works because bits coming from sign extension have the same value as
   // the sign bit of the original value; performing ashr instead of lshr
   // generates bits of the same value as the sign bit.
   if (Src->hasOneUse() &&
-      match(Src, m_LShr(m_SExt(m_Value(A)), m_ConstantInt(Cst))) &&
-      cast<Instruction>(Src)->getOperand(0)->hasOneUse()) {
+      match(Src, m_LShr(m_SExt(m_Value(A)), m_ConstantInt(Cst)))) {
+    Value *SExt = cast<Instruction>(Src)->getOperand(0);
+    const unsigned SExtSize = SExt->getType()->getPrimitiveSizeInBits();
     const unsigned ASize = A->getType()->getPrimitiveSizeInBits();
+    const unsigned CISize = CI.getType()->getPrimitiveSizeInBits();
+    const unsigned MaxAmt = SExtSize - std::max(CISize, ASize);
+    unsigned ShiftAmt = Cst->getZExtValue();
+
     // This optimization can be only performed when zero bits generated by
     // the original lshr aren't pulled into the value after truncation, so we
-    // can only shift by values smaller than the size of destination type (in
-    // bits).
-    if (Cst->getValue().ult(ASize)) {
-      Value *Shift = Builder->CreateAShr(A, Cst->getZExtValue());
-      Shift->takeName(Src);
-      return CastInst::CreateIntegerCast(Shift, CI.getType(), true);
+    // can only shift by values no larger than the number of extension bits.
+    // FIXME: Instead of bailing when the shift is too large, use and to clear
+    // the extra bits.
+    if (ShiftAmt <= MaxAmt) {
+      if (CISize == ASize)
+        return BinaryOperator::CreateAShr(A, ConstantInt::get(CI.getType(),
+                                          std::min(ShiftAmt, ASize - 1)));
+      if (SExt->hasOneUse()) {
+        Value *Shift = Builder.CreateAShr(A, std::min(ShiftAmt, ASize - 1));
+        Shift->takeName(Src);
+        return CastInst::CreateIntegerCast(Shift, CI.getType(), true);
+      }
     }
   }
 
   if (Instruction *I = shrinkBitwiseLogic(CI))
     return I;
 
+  if (Instruction *I = shrinkSplatShuffle(CI, Builder))
+    return I;
+
+  if (Instruction *I = shrinkInsertElt(CI, Builder))
+    return I;
+
   if (Src->hasOneUse() && isa<IntegerType>(SrcTy) &&
-      ShouldChangeType(SrcTy, DestTy)) {
+      shouldChangeType(SrcTy, DestTy)) {
     // Transform "trunc (shl X, cst)" -> "shl (trunc X), cst" so long as the
     // dest type is native and cst < dest size.
     if (match(Src, m_Shl(m_Value(A), m_ConstantInt(Cst))) &&
@@ -564,7 +635,7 @@ Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
       // FoldShiftByConstant and is the extend in reg pattern.
       const unsigned DestSize = DestTy->getScalarSizeInBits();
       if (Cst->getValue().ult(DestSize)) {
-        Value *NewTrunc = Builder->CreateTrunc(A, DestTy, A->getName() + ".tr");
+        Value *NewTrunc = Builder.CreateTrunc(A, DestTy, A->getName() + ".tr");
 
         return BinaryOperator::Create(
           Instruction::Shl, NewTrunc,
@@ -573,7 +644,7 @@ Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
     }
   }
 
-  if (Instruction *I = foldVecTruncToExtElt(CI, *this, DL))
+  if (Instruction *I = foldVecTruncToExtElt(CI, *this))
     return I;
 
   return nullptr;
@@ -589,20 +660,20 @@ Instruction *InstCombiner::transformZExtICmp(ICmpInst *ICI, ZExtInst &CI,
 
     // zext (x <s  0) to i32 --> x>>u31      true if signbit set.
     // zext (x >s -1) to i32 --> (x>>u31)^1  true if signbit clear.
-    if ((ICI->getPredicate() == ICmpInst::ICMP_SLT && Op1CV == 0) ||
+    if ((ICI->getPredicate() == ICmpInst::ICMP_SLT && Op1CV.isNullValue()) ||
         (ICI->getPredicate() == ICmpInst::ICMP_SGT && Op1CV.isAllOnesValue())) {
       if (!DoTransform) return ICI;
 
       Value *In = ICI->getOperand(0);
       Value *Sh = ConstantInt::get(In->getType(),
                                    In->getType()->getScalarSizeInBits() - 1);
-      In = Builder->CreateLShr(In, Sh, In->getName() + ".lobit");
+      In = Builder.CreateLShr(In, Sh, In->getName() + ".lobit");
       if (In->getType() != CI.getType())
-        In = Builder->CreateIntCast(In, CI.getType(), false/*ZExt*/);
+        In = Builder.CreateIntCast(In, CI.getType(), false /*ZExt*/);
 
       if (ICI->getPredicate() == ICmpInst::ICMP_SGT) {
         Constant *One = ConstantInt::get(In->getType(), 1);
-        In = Builder->CreateXor(In, One, In->getName() + ".not");
+        In = Builder.CreateXor(In, One, In->getName() + ".not");
       }
 
       return replaceInstUsesWith(CI, In);
@@ -616,20 +687,18 @@ Instruction *InstCombiner::transformZExtICmp(ICmpInst *ICI, ZExtInst &CI,
     // zext (X != 0) to i32 --> X>>1     iff X has only the 2nd bit set.
     // zext (X != 1) to i32 --> X^1      iff X has only the low bit set.
     // zext (X != 2) to i32 --> (X>>1)^1 iff X has only the 2nd bit set.
-    if ((Op1CV == 0 || Op1CV.isPowerOf2()) &&
+    if ((Op1CV.isNullValue() || Op1CV.isPowerOf2()) &&
         // This only works for EQ and NE
         ICI->isEquality()) {
       // If Op1C some other power of two, convert:
-      uint32_t BitWidth = Op1C->getType()->getBitWidth();
-      APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
-      computeKnownBits(ICI->getOperand(0), KnownZero, KnownOne, 0, &CI);
+      KnownBits Known = computeKnownBits(ICI->getOperand(0), 0, &CI);
 
-      APInt KnownZeroMask(~KnownZero);
+      APInt KnownZeroMask(~Known.Zero);
       if (KnownZeroMask.isPowerOf2()) { // Exactly 1 possible 1?
         if (!DoTransform) return ICI;
 
         bool isNE = ICI->getPredicate() == ICmpInst::ICMP_NE;
-        if (Op1CV != 0 && (Op1CV != KnownZeroMask)) {
+        if (!Op1CV.isNullValue() && (Op1CV != KnownZeroMask)) {
           // (X&4) == 2 --> false
           // (X&4) != 2 --> true
           Constant *Res = ConstantInt::get(Type::getInt1Ty(CI.getContext()),
@@ -643,19 +712,19 @@ Instruction *InstCombiner::transformZExtICmp(ICmpInst *ICI, ZExtInst &CI,
         if (ShAmt) {
           // Perform a logical shr by shiftamt.
           // Insert the shift to put the result in the low bit.
-          In = Builder->CreateLShr(In, ConstantInt::get(In->getType(), ShAmt),
-                                   In->getName() + ".lobit");
+          In = Builder.CreateLShr(In, ConstantInt::get(In->getType(), ShAmt),
+                                  In->getName() + ".lobit");
         }
 
-        if ((Op1CV != 0) == isNE) { // Toggle the low bit.
+        if (!Op1CV.isNullValue() == isNE) { // Toggle the low bit.
           Constant *One = ConstantInt::get(In->getType(), 1);
-          In = Builder->CreateXor(In, One);
+          In = Builder.CreateXor(In, One);
         }
 
         if (CI.getType() == In->getType())
           return replaceInstUsesWith(CI, In);
 
-        Value *IntCast = Builder->CreateIntCast(In, CI.getType(), false);
+        Value *IntCast = Builder.CreateIntCast(In, CI.getType(), false);
         return replaceInstUsesWith(CI, IntCast);
       }
     }
@@ -666,34 +735,31 @@ Instruction *InstCombiner::transformZExtICmp(ICmpInst *ICI, ZExtInst &CI,
   // may lead to additional simplifications.
   if (ICI->isEquality() && CI.getType() == ICI->getOperand(0)->getType()) {
     if (IntegerType *ITy = dyn_cast<IntegerType>(CI.getType())) {
-      uint32_t BitWidth = ITy->getBitWidth();
       Value *LHS = ICI->getOperand(0);
       Value *RHS = ICI->getOperand(1);
 
-      APInt KnownZeroLHS(BitWidth, 0), KnownOneLHS(BitWidth, 0);
-      APInt KnownZeroRHS(BitWidth, 0), KnownOneRHS(BitWidth, 0);
-      computeKnownBits(LHS, KnownZeroLHS, KnownOneLHS, 0, &CI);
-      computeKnownBits(RHS, KnownZeroRHS, KnownOneRHS, 0, &CI);
+      KnownBits KnownLHS = computeKnownBits(LHS, 0, &CI);
+      KnownBits KnownRHS = computeKnownBits(RHS, 0, &CI);
 
-      if (KnownZeroLHS == KnownZeroRHS && KnownOneLHS == KnownOneRHS) {
-        APInt KnownBits = KnownZeroLHS | KnownOneLHS;
+      if (KnownLHS.Zero == KnownRHS.Zero && KnownLHS.One == KnownRHS.One) {
+        APInt KnownBits = KnownLHS.Zero | KnownLHS.One;
         APInt UnknownBit = ~KnownBits;
         if (UnknownBit.countPopulation() == 1) {
           if (!DoTransform) return ICI;
 
-          Value *Result = Builder->CreateXor(LHS, RHS);
+          Value *Result = Builder.CreateXor(LHS, RHS);
 
           // Mask off any bits that are set and won't be shifted away.
-          if (KnownOneLHS.uge(UnknownBit))
-            Result = Builder->CreateAnd(Result,
+          if (KnownLHS.One.uge(UnknownBit))
+            Result = Builder.CreateAnd(Result,
                                         ConstantInt::get(ITy, UnknownBit));
 
           // Shift the bit we're testing down to the lsb.
-          Result = Builder->CreateLShr(
+          Result = Builder.CreateLShr(
                Result, ConstantInt::get(ITy, UnknownBit.countTrailingZeros()));
 
           if (ICI->getPredicate() == ICmpInst::ICMP_EQ)
-            Result = Builder->CreateXor(Result, ConstantInt::get(ITy, 1));
+            Result = Builder.CreateXor(Result, ConstantInt::get(ITy, 1));
           Result->takeName(ICI);
           return replaceInstUsesWith(CI, Result);
         }
@@ -838,11 +904,6 @@ Instruction *InstCombiner::visitZExt(ZExtInst &CI) {
   if (Instruction *Result = commonCastTransforms(CI))
     return Result;
 
-  // See if we can simplify any instructions used by the input whose sole
-  // purpose is to compute bits we don't care about.
-  if (SimplifyDemandedInstructionBits(CI))
-    return &CI;
-
   Value *Src = CI.getOperand(0);
   Type *SrcTy = Src->getType(), *DestTy = CI.getType();
 
@@ -851,10 +912,10 @@ Instruction *InstCombiner::visitZExt(ZExtInst &CI) {
   // expression tree to something weird like i93 unless the source is also
   // strange.
   unsigned BitsToClear;
-  if ((DestTy->isVectorTy() || ShouldChangeType(SrcTy, DestTy)) &&
+  if ((DestTy->isVectorTy() || shouldChangeType(SrcTy, DestTy)) &&
       canEvaluateZExtd(Src, DestTy, BitsToClear, *this, &CI)) {
-    assert(BitsToClear < SrcTy->getScalarSizeInBits() &&
-           "Unreasonable BitsToClear");
+    assert(BitsToClear <= SrcTy->getScalarSizeInBits() &&
+           "Can't clear more bits than in SrcTy");
 
     // Okay, we can transform this!  Insert the new expression now.
     DEBUG(dbgs() << "ICE: EvaluateInDifferentType converting expression type"
@@ -898,7 +959,7 @@ Instruction *InstCombiner::visitZExt(ZExtInst &CI) {
     if (SrcSize < DstSize) {
       APInt AndValue(APInt::getLowBitsSet(SrcSize, MidSize));
       Constant *AndConst = ConstantInt::get(A->getType(), AndValue);
-      Value *And = Builder->CreateAnd(A, AndConst, CSrc->getName()+".mask");
+      Value *And = Builder.CreateAnd(A, AndConst, CSrc->getName() + ".mask");
       return new ZExtInst(And, CI.getType());
     }
 
@@ -908,7 +969,7 @@ Instruction *InstCombiner::visitZExt(ZExtInst &CI) {
                                                            AndValue));
     }
     if (SrcSize > DstSize) {
-      Value *Trunc = Builder->CreateTrunc(A, CI.getType());
+      Value *Trunc = Builder.CreateTrunc(A, CI.getType());
       APInt AndValue(APInt::getLowBitsSet(DstSize, MidSize));
       return BinaryOperator::CreateAnd(Trunc,
                                        ConstantInt::get(Trunc->getType(),
@@ -930,8 +991,8 @@ Instruction *InstCombiner::visitZExt(ZExtInst &CI) {
         (transformZExtICmp(LHS, CI, false) ||
          transformZExtICmp(RHS, CI, false))) {
       // zext (or icmp, icmp) -> or (zext icmp), (zext icmp)
-      Value *LCast = Builder->CreateZExt(LHS, CI.getType(), LHS->getName());
-      Value *RCast = Builder->CreateZExt(RHS, CI.getType(), RHS->getName());
+      Value *LCast = Builder.CreateZExt(LHS, CI.getType(), LHS->getName());
+      Value *RCast = Builder.CreateZExt(RHS, CI.getType(), RHS->getName());
       BinaryOperator *Or = BinaryOperator::Create(Instruction::Or, LCast, RCast);
 
       // Perform the elimination.
@@ -958,7 +1019,7 @@ Instruction *InstCombiner::visitZExt(ZExtInst &CI) {
       match(And, m_OneUse(m_And(m_Trunc(m_Value(X)), m_Specific(C)))) &&
       X->getType() == CI.getType()) {
     Constant *ZC = ConstantExpr::getZExt(C, CI.getType());
-    return BinaryOperator::CreateXor(Builder->CreateAnd(X, ZC), ZC);
+    return BinaryOperator::CreateXor(Builder.CreateAnd(X, ZC), ZC);
   }
 
   return nullptr;
@@ -981,12 +1042,12 @@ Instruction *InstCombiner::transformSExtICmp(ICmpInst *ICI, Instruction &CI) {
 
       Value *Sh = ConstantInt::get(Op0->getType(),
                                    Op0->getType()->getScalarSizeInBits()-1);
-      Value *In = Builder->CreateAShr(Op0, Sh, Op0->getName()+".lobit");
+      Value *In = Builder.CreateAShr(Op0, Sh, Op0->getName() + ".lobit");
       if (In->getType() != CI.getType())
-        In = Builder->CreateIntCast(In, CI.getType(), true/*SExt*/);
+        In = Builder.CreateIntCast(In, CI.getType(), true /*SExt*/);
 
       if (Pred == ICmpInst::ICMP_SGT)
-        In = Builder->CreateNot(In, In->getName()+".not");
+        In = Builder.CreateNot(In, In->getName() + ".not");
       return replaceInstUsesWith(CI, In);
     }
   }
@@ -997,11 +1058,9 @@ Instruction *InstCombiner::transformSExtICmp(ICmpInst *ICI, Instruction &CI) {
     // the icmp and sext into bitwise/integer operations.
     if (ICI->hasOneUse() &&
         ICI->isEquality() && (Op1C->isZero() || Op1C->getValue().isPowerOf2())){
-      unsigned BitWidth = Op1C->getType()->getBitWidth();
-      APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
-      computeKnownBits(Op0, KnownZero, KnownOne, 0, &CI);
+      KnownBits Known = computeKnownBits(Op0, 0, &CI);
 
-      APInt KnownZeroMask(~KnownZero);
+      APInt KnownZeroMask(~Known.Zero);
       if (KnownZeroMask.isPowerOf2()) {
         Value *In = ICI->getOperand(0);
 
@@ -1019,26 +1078,26 @@ Instruction *InstCombiner::transformSExtICmp(ICmpInst *ICI, Instruction &CI) {
           unsigned ShiftAmt = KnownZeroMask.countTrailingZeros();
           // Perform a right shift to place the desired bit in the LSB.
           if (ShiftAmt)
-            In = Builder->CreateLShr(In,
-                                     ConstantInt::get(In->getType(), ShiftAmt));
+            In = Builder.CreateLShr(In,
+                                    ConstantInt::get(In->getType(), ShiftAmt));
 
           // At this point "In" is either 1 or 0. Subtract 1 to turn
           // {1, 0} -> {0, -1}.
-          In = Builder->CreateAdd(In,
-                                  ConstantInt::getAllOnesValue(In->getType()),
-                                  "sext");
+          In = Builder.CreateAdd(In,
+                                 ConstantInt::getAllOnesValue(In->getType()),
+                                 "sext");
         } else {
           // sext ((x & 2^n) != 0)   -> (x << bitwidth-n) a>> bitwidth-1
           // sext ((x & 2^n) == 2^n) -> (x << bitwidth-n) a>> bitwidth-1
           unsigned ShiftAmt = KnownZeroMask.countLeadingZeros();
           // Perform a left shift to place the desired bit in the MSB.
           if (ShiftAmt)
-            In = Builder->CreateShl(In,
-                                    ConstantInt::get(In->getType(), ShiftAmt));
+            In = Builder.CreateShl(In,
+                                   ConstantInt::get(In->getType(), ShiftAmt));
 
           // Distribute the bit over the whole bit width.
-          In = Builder->CreateAShr(In, ConstantInt::get(In->getType(),
-                                                        BitWidth - 1), "sext");
+          In = Builder.CreateAShr(In, ConstantInt::get(In->getType(),
+                                  KnownZeroMask.getBitWidth() - 1), "sext");
         }
 
         if (CI.getType() == In->getType())
@@ -1124,20 +1183,14 @@ Instruction *InstCombiner::visitSExt(SExtInst &CI) {
   if (Instruction *I = commonCastTransforms(CI))
     return I;
 
-  // See if we can simplify any instructions used by the input whose sole
-  // purpose is to compute bits we don't care about.
-  if (SimplifyDemandedInstructionBits(CI))
-    return &CI;
-
   Value *Src = CI.getOperand(0);
   Type *SrcTy = Src->getType(), *DestTy = CI.getType();
 
   // If we know that the value being extended is positive, we can use a zext
   // instead.
-  bool KnownZero, KnownOne;
-  ComputeSignBit(Src, KnownZero, KnownOne, 0, &CI);
-  if (KnownZero) {
-    Value *ZExt = Builder->CreateZExt(Src, DestTy);
+  KnownBits Known = computeKnownBits(Src, 0, &CI);
+  if (Known.isNonNegative()) {
+    Value *ZExt = Builder.CreateZExt(Src, DestTy);
     return replaceInstUsesWith(CI, ZExt);
   }
 
@@ -1145,7 +1198,7 @@ Instruction *InstCombiner::visitSExt(SExtInst &CI) {
   // type.   Only do this if the dest type is a simple type, don't convert the
   // expression tree to something weird like i93 unless the source is also
   // strange.
-  if ((DestTy->isVectorTy() || ShouldChangeType(SrcTy, DestTy)) &&
+  if ((DestTy->isVectorTy() || shouldChangeType(SrcTy, DestTy)) &&
       canEvaluateSExtd(Src, DestTy)) {
     // Okay, we can transform this!  Insert the new expression now.
     DEBUG(dbgs() << "ICE: EvaluateInDifferentType converting expression type"
@@ -1163,22 +1216,20 @@ Instruction *InstCombiner::visitSExt(SExtInst &CI) {
 
     // We need to emit a shl + ashr to do the sign extend.
     Value *ShAmt = ConstantInt::get(DestTy, DestBitSize-SrcBitSize);
-    return BinaryOperator::CreateAShr(Builder->CreateShl(Res, ShAmt, "sext"),
+    return BinaryOperator::CreateAShr(Builder.CreateShl(Res, ShAmt, "sext"),
                                       ShAmt);
   }
 
-  // If this input is a trunc from our destination, then turn sext(trunc(x))
+  // If the input is a trunc from the destination type, then turn sext(trunc(x))
   // into shifts.
-  if (TruncInst *TI = dyn_cast<TruncInst>(Src))
-    if (TI->hasOneUse() && TI->getOperand(0)->getType() == DestTy) {
-      uint32_t SrcBitSize = SrcTy->getScalarSizeInBits();
-      uint32_t DestBitSize = DestTy->getScalarSizeInBits();
-
-      // We need to emit a shl + ashr to do the sign extend.
-      Value *ShAmt = ConstantInt::get(DestTy, DestBitSize-SrcBitSize);
-      Value *Res = Builder->CreateShl(TI->getOperand(0), ShAmt, "sext");
-      return BinaryOperator::CreateAShr(Res, ShAmt);
-    }
+  Value *X;
+  if (match(Src, m_OneUse(m_Trunc(m_Value(X)))) && X->getType() == DestTy) {
+    // sext(trunc(X)) --> ashr(shl(X, C), C)
+    unsigned SrcBitSize = SrcTy->getScalarSizeInBits();
+    unsigned DestBitSize = DestTy->getScalarSizeInBits();
+    Constant *ShAmt = ConstantInt::get(DestTy, DestBitSize - SrcBitSize);
+    return BinaryOperator::CreateAShr(Builder.CreateShl(X, ShAmt), ShAmt);
+  }
 
   if (ICmpInst *ICI = dyn_cast<ICmpInst>(Src))
     return transformSExtICmp(ICI, CI);
@@ -1206,7 +1257,7 @@ Instruction *InstCombiner::visitSExt(SExtInst &CI) {
     unsigned SrcDstSize = CI.getType()->getScalarSizeInBits();
     unsigned ShAmt = CA->getZExtValue()+SrcDstSize-MidSize;
     Constant *ShAmtV = ConstantInt::get(CI.getType(), ShAmt);
-    A = Builder->CreateShl(A, ShAmtV, CI.getName());
+    A = Builder.CreateShl(A, ShAmtV, CI.getName());
     return BinaryOperator::CreateAShr(A, ShAmtV);
   }
 
@@ -1225,17 +1276,15 @@ static Constant *fitsInFPType(ConstantFP *CFP, const fltSemantics &Sem) {
   return nullptr;
 }
 
-/// If this is a floating-point extension instruction, look
-/// through it until we get the source value.
+/// Look through floating-point extensions until we get the source value.
 static Value *lookThroughFPExtensions(Value *V) {
-  if (Instruction *I = dyn_cast<Instruction>(V))
-    if (I->getOpcode() == Instruction::FPExt)
-      return lookThroughFPExtensions(I->getOperand(0));
+  while (auto *FPExt = dyn_cast<FPExtInst>(V))
+    V = FPExt->getOperand(0);
 
   // If this value is a constant, return the constant in the smallest FP type
   // that can accurately represent it.  This allows us to turn
   // (float)((double)X+2.0) into x+2.0f.
-  if (ConstantFP *CFP = dyn_cast<ConstantFP>(V)) {
+  if (auto *CFP = dyn_cast<ConstantFP>(V)) {
     if (CFP->getType() == Type::getPPC_FP128Ty(V->getContext()))
       return V;  // No constant folding of this.
     // See if the value can be truncated to half and then reextended.
@@ -1297,9 +1346,9 @@ Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) {
         // case of interest here is (float)((double)float + float)).
         if (OpWidth >= 2*DstWidth+1 && DstWidth >= SrcWidth) {
           if (LHSOrig->getType() != CI.getType())
-            LHSOrig = Builder->CreateFPExt(LHSOrig, CI.getType());
+            LHSOrig = Builder.CreateFPExt(LHSOrig, CI.getType());
           if (RHSOrig->getType() != CI.getType())
-            RHSOrig = Builder->CreateFPExt(RHSOrig, CI.getType());
+            RHSOrig = Builder.CreateFPExt(RHSOrig, CI.getType());
           Instruction *RI =
             BinaryOperator::Create(OpI->getOpcode(), LHSOrig, RHSOrig);
           RI->copyFastMathFlags(OpI);
@@ -1314,9 +1363,9 @@ Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) {
         // in the destination format if it can represent both sources.
         if (OpWidth >= LHSWidth + RHSWidth && DstWidth >= SrcWidth) {
           if (LHSOrig->getType() != CI.getType())
-            LHSOrig = Builder->CreateFPExt(LHSOrig, CI.getType());
+            LHSOrig = Builder.CreateFPExt(LHSOrig, CI.getType());
           if (RHSOrig->getType() != CI.getType())
-            RHSOrig = Builder->CreateFPExt(RHSOrig, CI.getType());
+            RHSOrig = Builder.CreateFPExt(RHSOrig, CI.getType());
           Instruction *RI =
             BinaryOperator::CreateFMul(LHSOrig, RHSOrig);
           RI->copyFastMathFlags(OpI);
@@ -1332,9 +1381,9 @@ Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) {
         // TODO: Tighten bound via rigorous analysis of the unbalanced case.
         if (OpWidth >= 2*DstWidth && DstWidth >= SrcWidth) {
           if (LHSOrig->getType() != CI.getType())
-            LHSOrig = Builder->CreateFPExt(LHSOrig, CI.getType());
+            LHSOrig = Builder.CreateFPExt(LHSOrig, CI.getType());
           if (RHSOrig->getType() != CI.getType())
-            RHSOrig = Builder->CreateFPExt(RHSOrig, CI.getType());
+            RHSOrig = Builder.CreateFPExt(RHSOrig, CI.getType());
           Instruction *RI =
             BinaryOperator::CreateFDiv(LHSOrig, RHSOrig);
           RI->copyFastMathFlags(OpI);
@@ -1349,11 +1398,11 @@ Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) {
         if (SrcWidth == OpWidth)
           break;
         if (LHSWidth < SrcWidth)
-          LHSOrig = Builder->CreateFPExt(LHSOrig, RHSOrig->getType());
+          LHSOrig = Builder.CreateFPExt(LHSOrig, RHSOrig->getType());
         else if (RHSWidth <= SrcWidth)
-          RHSOrig = Builder->CreateFPExt(RHSOrig, LHSOrig->getType());
+          RHSOrig = Builder.CreateFPExt(RHSOrig, LHSOrig->getType());
         if (LHSOrig != OpI->getOperand(0) || RHSOrig != OpI->getOperand(1)) {
-          Value *ExactResult = Builder->CreateFRem(LHSOrig, RHSOrig);
+          Value *ExactResult = Builder.CreateFRem(LHSOrig, RHSOrig);
           if (Instruction *RI = dyn_cast<Instruction>(ExactResult))
             RI->copyFastMathFlags(OpI);
           return CastInst::CreateFPCast(ExactResult, CI.getType());
@@ -1362,8 +1411,8 @@ Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) {
 
     // (fptrunc (fneg x)) -> (fneg (fptrunc x))
     if (BinaryOperator::isFNeg(OpI)) {
-      Value *InnerTrunc = Builder->CreateFPTrunc(OpI->getOperand(1),
-                                                 CI.getType());
+      Value *InnerTrunc = Builder.CreateFPTrunc(OpI->getOperand(1),
+                                                CI.getType());
       Instruction *RI = BinaryOperator::CreateFNeg(InnerTrunc);
       RI->copyFastMathFlags(OpI);
       return RI;
@@ -1382,34 +1431,57 @@ Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) {
       (isa<ConstantFP>(SI->getOperand(1)) ||
        isa<ConstantFP>(SI->getOperand(2))) &&
       matchSelectPattern(SI, LHS, RHS).Flavor == SPF_UNKNOWN) {
-    Value *LHSTrunc = Builder->CreateFPTrunc(SI->getOperand(1),
-                                             CI.getType());
-    Value *RHSTrunc = Builder->CreateFPTrunc(SI->getOperand(2),
-                                             CI.getType());
+    Value *LHSTrunc = Builder.CreateFPTrunc(SI->getOperand(1), CI.getType());
+    Value *RHSTrunc = Builder.CreateFPTrunc(SI->getOperand(2), CI.getType());
     return SelectInst::Create(SI->getOperand(0), LHSTrunc, RHSTrunc);
   }
 
   IntrinsicInst *II = dyn_cast<IntrinsicInst>(CI.getOperand(0));
   if (II) {
     switch (II->getIntrinsicID()) {
-      default: break;
-      case Intrinsic::fabs: {
-        // (fptrunc (fabs x)) -> (fabs (fptrunc x))
-        Value *InnerTrunc = Builder->CreateFPTrunc(II->getArgOperand(0),
-                                                   CI.getType());
-        Type *IntrinsicType[] = { CI.getType() };
-        Function *Overload = Intrinsic::getDeclaration(
-            CI.getModule(), II->getIntrinsicID(), IntrinsicType);
-
-        SmallVector<OperandBundleDef, 1> OpBundles;
-        II->getOperandBundlesAsDefs(OpBundles);
-
-        Value *Args[] = { InnerTrunc };
-        return CallInst::Create(Overload, Args, OpBundles, II->getName());
+    default: break;
+    case Intrinsic::fabs:
+    case Intrinsic::ceil:
+    case Intrinsic::floor:
+    case Intrinsic::rint:
+    case Intrinsic::round:
+    case Intrinsic::nearbyint:
+    case Intrinsic::trunc: {
+      Value *Src = II->getArgOperand(0);
+      if (!Src->hasOneUse())
+        break;
+
+      // Except for fabs, this transformation requires the input of the unary FP
+      // operation to be itself an fpext from the type to which we're
+      // truncating.
+      if (II->getIntrinsicID() != Intrinsic::fabs) {
+        FPExtInst *FPExtSrc = dyn_cast<FPExtInst>(Src);
+        if (!FPExtSrc || FPExtSrc->getOperand(0)->getType() != CI.getType())
+          break;
       }
+
+      // Do unary FP operation on smaller type.
+      // (fptrunc (fabs x)) -> (fabs (fptrunc x))
+      Value *InnerTrunc = Builder.CreateFPTrunc(Src, CI.getType());
+      Type *IntrinsicType[] = { CI.getType() };
+      Function *Overload = Intrinsic::getDeclaration(
+        CI.getModule(), II->getIntrinsicID(), IntrinsicType);
+
+      SmallVector<OperandBundleDef, 1> OpBundles;
+      II->getOperandBundlesAsDefs(OpBundles);
+
+      Value *Args[] = { InnerTrunc };
+      CallInst *NewCI =  CallInst::Create(Overload, Args,
+                                          OpBundles, II->getName());
+      NewCI->copyFastMathFlags(II);
+      return NewCI;
+    }
     }
   }
 
+  if (Instruction *I = shrinkInsertElt(CI, Builder))
+    return I;
+
   return nullptr;
 }
 
@@ -1502,7 +1574,7 @@ Instruction *InstCombiner::visitIntToPtr(IntToPtrInst &CI) {
     if (CI.getType()->isVectorTy()) // Handle vectors of pointers.
       Ty = VectorType::get(Ty, CI.getType()->getVectorNumElements());
 
-    Value *P = Builder->CreateZExtOrTrunc(CI.getOperand(0), Ty);
+    Value *P = Builder.CreateZExtOrTrunc(CI.getOperand(0), Ty);
     return new IntToPtrInst(P, CI.getType());
   }
 
@@ -1524,7 +1596,7 @@ Instruction *InstCombiner::commonPointerCastTransforms(CastInst &CI) {
         // GEP into CI would undo canonicalizing addrspacecast with different
         // pointer types, causing infinite loops.
         (!isa<AddrSpaceCastInst>(CI) ||
-          GEP->getType() == GEP->getPointerOperand()->getType())) {
+         GEP->getType() == GEP->getPointerOperandType())) {
       // Changing the cast operand is usually not a good idea but it is safe
       // here because the pointer operand is being replaced with another
       // pointer operand so the opcode doesn't need to change.
@@ -1552,7 +1624,7 @@ Instruction *InstCombiner::visitPtrToInt(PtrToIntInst &CI) {
   if (Ty->isVectorTy()) // Handle vectors of pointers.
     PtrTy = VectorType::get(PtrTy, Ty->getVectorNumElements());
 
-  Value *P = Builder->CreatePtrToInt(CI.getOperand(0), PtrTy);
+  Value *P = Builder.CreatePtrToInt(CI.getOperand(0), PtrTy);
   return CastInst::CreateIntegerCast(P, Ty, /*isSigned=*/false);
 }
 
@@ -1578,7 +1650,7 @@ static Instruction *optimizeVectorResize(Value *InVal, VectorType *DestTy,
       return nullptr;
 
     SrcTy = VectorType::get(DestTy->getElementType(), SrcTy->getNumElements());
-    InVal = IC.Builder->CreateBitCast(InVal, SrcTy);
+    InVal = IC.Builder.CreateBitCast(InVal, SrcTy);
   }
 
   // Now that the element types match, get the shuffle mask and RHS of the
@@ -1758,8 +1830,8 @@ static Value *optimizeIntegerToVectorInsertions(BitCastInst &CI,
   for (unsigned i = 0, e = Elements.size(); i != e; ++i) {
     if (!Elements[i]) continue;  // Unset element.
 
-    Result = IC.Builder->CreateInsertElement(Result, Elements[i],
-                                             IC.Builder->getInt32(i));
+    Result = IC.Builder.CreateInsertElement(Result, Elements[i],
+                                            IC.Builder.getInt32(i));
   }
 
   return Result;
@@ -1770,8 +1842,7 @@ static Value *optimizeIntegerToVectorInsertions(BitCastInst &CI,
 /// vectors better than bitcasts of scalars because vector registers are
 /// usually not type-specific like scalar integer or scalar floating-point.
 static Instruction *canonicalizeBitCastExtElt(BitCastInst &BitCast,
-                                              InstCombiner &IC,
-                                              const DataLayout &DL) {
+                                              InstCombiner &IC) {
   // TODO: Create and use a pattern matcher for ExtractElementInst.
   auto *ExtElt = dyn_cast<ExtractElementInst>(BitCast.getOperand(0));
   if (!ExtElt || !ExtElt->hasOneUse())
@@ -1785,8 +1856,8 @@ static Instruction *canonicalizeBitCastExtElt(BitCastInst &BitCast,
 
   unsigned NumElts = ExtElt->getVectorOperandType()->getNumElements();
   auto *NewVecType = VectorType::get(DestType, NumElts);
-  auto *NewBC = IC.Builder->CreateBitCast(ExtElt->getVectorOperand(),
-                                          NewVecType, "bc");
+  auto *NewBC = IC.Builder.CreateBitCast(ExtElt->getVectorOperand(),
+                                         NewVecType, "bc");
   return ExtractElementInst::Create(NewBC, ExtElt->getIndexOperand());
 }
 
@@ -1795,7 +1866,7 @@ static Instruction *foldBitCastBitwiseLogic(BitCastInst &BitCast,
                                             InstCombiner::BuilderTy &Builder) {
   Type *DestTy = BitCast.getType();
   BinaryOperator *BO;
-  if (!DestTy->getScalarType()->isIntegerTy() ||
+  if (!DestTy->isIntOrIntVectorTy() ||
       !match(BitCast.getOperand(0), m_OneUse(m_BinOp(BO))) ||
       !BO->isBitwiseLogicOp())
     return nullptr;
@@ -1821,6 +1892,18 @@ static Instruction *foldBitCastBitwiseLogic(BitCastInst &BitCast,
     return BinaryOperator::Create(BO->getOpcode(), CastedOp0, X);
   }
 
+  // Canonicalize vector bitcasts to come before vector bitwise logic with a
+  // constant. This eases recognition of special constants for later ops.
+  // Example:
+  // icmp u/s (a ^ signmask), (b ^ signmask) --> icmp s/u a, b
+  Constant *C;
+  if (match(BO->getOperand(1), m_Constant(C))) {
+    // bitcast (logic X, C) --> logic (bitcast X, C')
+    Value *CastedOp0 = Builder.CreateBitCast(BO->getOperand(0), DestTy);
+    Value *CastedC = ConstantExpr::getBitCast(C, DestTy);
+    return BinaryOperator::Create(BO->getOpcode(), CastedOp0, CastedC);
+  }
+
   return nullptr;
 }
 
@@ -1946,8 +2029,8 @@ Instruction *InstCombiner::optimizeBitCastFromPhi(CastInst &CI, PHINode *PN) {
   // For each old PHI node, create a corresponding new PHI node with a type A.
   SmallDenseMap<PHINode *, PHINode *> NewPNodes;
   for (auto *OldPN : OldPhiNodes) {
-    Builder->SetInsertPoint(OldPN);
-    PHINode *NewPN = Builder->CreatePHI(DestTy, OldPN->getNumOperands());
+    Builder.SetInsertPoint(OldPN);
+    PHINode *NewPN = Builder.CreatePHI(DestTy, OldPN->getNumOperands());
     NewPNodes[OldPN] = NewPN;
   }
 
@@ -1960,8 +2043,8 @@ Instruction *InstCombiner::optimizeBitCastFromPhi(CastInst &CI, PHINode *PN) {
       if (auto *C = dyn_cast<Constant>(V)) {
         NewV = ConstantExpr::getBitCast(C, DestTy);
       } else if (auto *LI = dyn_cast<LoadInst>(V)) {
-        Builder->SetInsertPoint(LI->getNextNode());
-        NewV = Builder->CreateBitCast(LI, DestTy);
+        Builder.SetInsertPoint(LI->getNextNode());
+        NewV = Builder.CreateBitCast(LI, DestTy);
         Worklist.Add(LI);
       } else if (auto *BCI = dyn_cast<BitCastInst>(V)) {
         NewV = BCI->getOperand(0);
@@ -1977,9 +2060,9 @@ Instruction *InstCombiner::optimizeBitCastFromPhi(CastInst &CI, PHINode *PN) {
   for (User *U : PN->users()) {
     auto *SI = dyn_cast<StoreInst>(U);
     if (SI && SI->isSimple() && SI->getOperand(0) == PN) {
-      Builder->SetInsertPoint(SI);
+      Builder.SetInsertPoint(SI);
       auto *NewBC =
-          cast<BitCastInst>(Builder->CreateBitCast(NewPNodes[PN], SrcTy));
+          cast<BitCastInst>(Builder.CreateBitCast(NewPNodes[PN], SrcTy));
       SI->setOperand(0, NewBC);
       Worklist.Add(SI);
       assert(hasStoreUsersOnly(*NewBC));
@@ -2034,14 +2117,14 @@ Instruction *InstCombiner::visitBitCast(BitCastInst &CI) {
 
     // If we found a path from the src to dest, create the getelementptr now.
     if (SrcElTy == DstElTy) {
-      SmallVector<Value *, 8> Idxs(NumZeros + 1, Builder->getInt32(0));
+      SmallVector<Value *, 8> Idxs(NumZeros + 1, Builder.getInt32(0));
       return GetElementPtrInst::CreateInBounds(Src, Idxs);
     }
   }
 
   if (VectorType *DestVTy = dyn_cast<VectorType>(DestTy)) {
     if (DestVTy->getNumElements() == 1 && !SrcTy->isVectorTy()) {
-      Value *Elem = Builder->CreateBitCast(Src, DestVTy->getElementType());
+      Value *Elem = Builder.CreateBitCast(Src, DestVTy->getElementType());
       return InsertElementInst::Create(UndefValue::get(DestTy), Elem,
                      Constant::getNullValue(Type::getInt32Ty(CI.getContext())));
       // FIXME: Canonicalize bitcast(insertelement) -> insertelement(bitcast)
@@ -2074,7 +2157,7 @@ Instruction *InstCombiner::visitBitCast(BitCastInst &CI) {
       // scalar-scalar cast.
       if (!DestTy->isVectorTy()) {
         Value *Elem =
-          Builder->CreateExtractElement(Src,
+          Builder.CreateExtractElement(Src,
                      Constant::getNullValue(Type::getInt32Ty(CI.getContext())));
         return CastInst::Create(Instruction::BitCast, Elem, DestTy);
       }
@@ -2103,8 +2186,8 @@ Instruction *InstCombiner::visitBitCast(BitCastInst &CI) {
            Tmp->getOperand(0)->getType() == DestTy) ||
           ((Tmp = dyn_cast<BitCastInst>(SVI->getOperand(1))) &&
            Tmp->getOperand(0)->getType() == DestTy)) {
-        Value *LHS = Builder->CreateBitCast(SVI->getOperand(0), DestTy);
-        Value *RHS = Builder->CreateBitCast(SVI->getOperand(1), DestTy);
+        Value *LHS = Builder.CreateBitCast(SVI->getOperand(0), DestTy);
+        Value *RHS = Builder.CreateBitCast(SVI->getOperand(1), DestTy);
         // Return a new shuffle vector.  Use the same element ID's, as we
         // know the vector types match #elts.
         return new ShuffleVectorInst(LHS, RHS, SVI->getOperand(2));
@@ -2117,13 +2200,13 @@ Instruction *InstCombiner::visitBitCast(BitCastInst &CI) {
     if (Instruction *I = optimizeBitCastFromPhi(CI, PN))
       return I;
 
-  if (Instruction *I = canonicalizeBitCastExtElt(CI, *this, DL))
+  if (Instruction *I = canonicalizeBitCastExtElt(CI, *this))
     return I;
 
-  if (Instruction *I = foldBitCastBitwiseLogic(CI, *Builder))
+  if (Instruction *I = foldBitCastBitwiseLogic(CI, Builder))
     return I;
 
-  if (Instruction *I = foldBitCastSelect(CI, *Builder))
+  if (Instruction *I = foldBitCastSelect(CI, Builder))
     return I;
 
   if (SrcTy->isPointerTy())
@@ -2147,7 +2230,7 @@ Instruction *InstCombiner::visitAddrSpaceCast(AddrSpaceCastInst &CI) {
       MidTy = VectorType::get(MidTy, VT->getNumElements());
     }
 
-    Value *NewBitCast = Builder->CreateBitCast(Src, MidTy);
+    Value *NewBitCast = Builder.CreateBitCast(Src, MidTy);
     return new AddrSpaceCastInst(NewBitCast, CI.getType());
   }