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, 128 insertions, 185 deletions

diff --git a/contrib/llvm/lib/IR/ConstantRange.cpp b/contrib/llvm/lib/IR/ConstantRange.cpp
index a85ad46..4bd1725 100644
--- a/contrib/llvm/lib/IR/ConstantRange.cpp
+++ b/contrib/llvm/lib/IR/ConstantRange.cpp
@@ -1,4 +1,4 @@
-//===-- ConstantRange.cpp - ConstantRange implementation ------------------===//
+//===- ConstantRange.cpp - ConstantRange implementation -------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -21,29 +21,31 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/IR/Instruction.h"
+#include "llvm/ADT/APInt.h"
+#include "llvm/IR/ConstantRange.h"
+#include "llvm/IR/Constants.h"
 #include "llvm/IR/InstrTypes.h"
+#include "llvm/IR/Instruction.h"
+#include "llvm/IR/Metadata.h"
 #include "llvm/IR/Operator.h"
-#include "llvm/IR/ConstantRange.h"
+#include "llvm/Support/Compiler.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <cassert>
+#include <cstdint>
+
 using namespace llvm;
 
-/// Initialize a full (the default) or empty set for the specified type.
-///
-ConstantRange::ConstantRange(uint32_t BitWidth, bool Full) {
-  if (Full)
-    Lower = Upper = APInt::getMaxValue(BitWidth);
-  else
-    Lower = Upper = APInt::getMinValue(BitWidth);
-}
+ConstantRange::ConstantRange(uint32_t BitWidth, bool Full)
+    : Lower(Full ? APInt::getMaxValue(BitWidth) : APInt::getMinValue(BitWidth)),
+      Upper(Lower) {}
 
-/// Initialize a range to hold the single specified value.
-///
-ConstantRange::ConstantRange(APIntMoveTy V)
+ConstantRange::ConstantRange(APInt V)
     : Lower(std::move(V)), Upper(Lower + 1) {}
 
-ConstantRange::ConstantRange(APIntMoveTy L, APIntMoveTy U)
+ConstantRange::ConstantRange(APInt L, APInt U)
     : Lower(std::move(L)), Upper(std::move(U)) {
   assert(Lower.getBitWidth() == Upper.getBitWidth() &&
          "ConstantRange with unequal bit widths");
@@ -70,49 +72,49 @@ ConstantRange ConstantRange::makeAllowedICmpRegion(CmpInst::Predicate Pred,
     APInt UMax(CR.getUnsignedMax());
     if (UMax.isMinValue())
       return ConstantRange(W, /* empty */ false);
-    return ConstantRange(APInt::getMinValue(W), UMax);
+    return ConstantRange(APInt::getMinValue(W), std::move(UMax));
   }
   case CmpInst::ICMP_SLT: {
     APInt SMax(CR.getSignedMax());
     if (SMax.isMinSignedValue())
       return ConstantRange(W, /* empty */ false);
-    return ConstantRange(APInt::getSignedMinValue(W), SMax);
+    return ConstantRange(APInt::getSignedMinValue(W), std::move(SMax));
   }
   case CmpInst::ICMP_ULE: {
     APInt UMax(CR.getUnsignedMax());
     if (UMax.isMaxValue())
       return ConstantRange(W);
-    return ConstantRange(APInt::getMinValue(W), UMax + 1);
+    return ConstantRange(APInt::getMinValue(W), std::move(UMax) + 1);
   }
   case CmpInst::ICMP_SLE: {
     APInt SMax(CR.getSignedMax());
     if (SMax.isMaxSignedValue())
       return ConstantRange(W);
-    return ConstantRange(APInt::getSignedMinValue(W), SMax + 1);
+    return ConstantRange(APInt::getSignedMinValue(W), std::move(SMax) + 1);
   }
   case CmpInst::ICMP_UGT: {
     APInt UMin(CR.getUnsignedMin());
     if (UMin.isMaxValue())
       return ConstantRange(W, /* empty */ false);
-    return ConstantRange(UMin + 1, APInt::getNullValue(W));
+    return ConstantRange(std::move(UMin) + 1, APInt::getNullValue(W));
   }
   case CmpInst::ICMP_SGT: {
     APInt SMin(CR.getSignedMin());
     if (SMin.isMaxSignedValue())
       return ConstantRange(W, /* empty */ false);
-    return ConstantRange(SMin + 1, APInt::getSignedMinValue(W));
+    return ConstantRange(std::move(SMin) + 1, APInt::getSignedMinValue(W));
   }
   case CmpInst::ICMP_UGE: {
     APInt UMin(CR.getUnsignedMin());
     if (UMin.isMinValue())
       return ConstantRange(W);
-    return ConstantRange(UMin, APInt::getNullValue(W));
+    return ConstantRange(std::move(UMin), APInt::getNullValue(W));
   }
   case CmpInst::ICMP_SGE: {
     APInt SMin(CR.getSignedMin());
     if (SMin.isMinSignedValue())
       return ConstantRange(W);
-    return ConstantRange(SMin, APInt::getSignedMinValue(W));
+    return ConstantRange(std::move(SMin), APInt::getSignedMinValue(W));
   }
   }
 }
@@ -177,7 +179,7 @@ ConstantRange
 ConstantRange::makeGuaranteedNoWrapRegion(Instruction::BinaryOps BinOp,
                                           const ConstantRange &Other,
                                           unsigned NoWrapKind) {
-  typedef OverflowingBinaryOperator OBO;
+  using OBO = OverflowingBinaryOperator;
 
   // Computes the intersection of CR0 and CR1.  It is different from
   // intersectWith in that the ConstantRange returned will only contain elements
@@ -202,7 +204,7 @@ ConstantRange::makeGuaranteedNoWrapRegion(Instruction::BinaryOps BinOp,
     return ConstantRange(BitWidth, false);
 
   if (auto *C = Other.getSingleElement())
-    if (C->isMinValue())
+    if (C->isNullValue())
       // Full set: nothing signed / unsigned wraps when added to 0.
       return ConstantRange(BitWidth);
 
@@ -214,8 +216,8 @@ ConstantRange::makeGuaranteedNoWrapRegion(Instruction::BinaryOps BinOp,
                                               -Other.getUnsignedMax()));
 
   if (NoWrapKind & OBO::NoSignedWrap) {
-    APInt SignedMin = Other.getSignedMin();
-    APInt SignedMax = Other.getSignedMax();
+    const APInt &SignedMin = Other.getSignedMin();
+    const APInt &SignedMax = Other.getSignedMax();
 
     if (SignedMax.isStrictlyPositive())
       Result = SubsetIntersect(
@@ -232,98 +234,76 @@ ConstantRange::makeGuaranteedNoWrapRegion(Instruction::BinaryOps BinOp,
   return Result;
 }
 
-/// isFullSet - Return true if this set contains all of the elements possible
-/// for this data-type
 bool ConstantRange::isFullSet() const {
   return Lower == Upper && Lower.isMaxValue();
 }
 
-/// isEmptySet - Return true if this set contains no members.
-///
 bool ConstantRange::isEmptySet() const {
   return Lower == Upper && Lower.isMinValue();
 }
 
-/// isWrappedSet - Return true if this set wraps around the top of the range,
-/// for example: [100, 8)
-///
 bool ConstantRange::isWrappedSet() const {
   return Lower.ugt(Upper);
 }
 
-/// isSignWrappedSet - Return true if this set wraps around the INT_MIN of
-/// its bitwidth, for example: i8 [120, 140).
-///
 bool ConstantRange::isSignWrappedSet() const {
   return contains(APInt::getSignedMaxValue(getBitWidth())) &&
          contains(APInt::getSignedMinValue(getBitWidth()));
 }
 
-/// getSetSize - Return the number of elements in this set.
-///
 APInt ConstantRange::getSetSize() const {
-  if (isFullSet()) {
-    APInt Size(getBitWidth()+1, 0);
-    Size.setBit(getBitWidth());
-    return Size;
-  }
+  if (isFullSet())
+    return APInt::getOneBitSet(getBitWidth()+1, getBitWidth());
 
   // This is also correct for wrapped sets.
   return (Upper - Lower).zext(getBitWidth()+1);
 }
 
-/// getUnsignedMax - Return the largest unsigned value contained in the
-/// ConstantRange.
-///
+bool
+ConstantRange::isSizeStrictlySmallerThan(const ConstantRange &Other) const {
+  assert(getBitWidth() == Other.getBitWidth());
+  if (isFullSet())
+    return false;
+  if (Other.isFullSet())
+    return true;
+  return (Upper - Lower).ult(Other.Upper - Other.Lower);
+}
+
+bool
+ConstantRange::isSizeLargerThan(uint64_t MaxSize) const {
+  assert(MaxSize && "MaxSize can't be 0.");
+  // If this a full set, we need special handling to avoid needing an extra bit
+  // to represent the size.
+  if (isFullSet())
+    return APInt::getMaxValue(getBitWidth()).ugt(MaxSize - 1);
+
+  return (Upper - Lower).ugt(MaxSize);
+}
+
 APInt ConstantRange::getUnsignedMax() const {
   if (isFullSet() || isWrappedSet())
     return APInt::getMaxValue(getBitWidth());
   return getUpper() - 1;
 }
 
-/// getUnsignedMin - Return the smallest unsigned value contained in the
-/// ConstantRange.
-///
 APInt ConstantRange::getUnsignedMin() const {
-  if (isFullSet() || (isWrappedSet() && getUpper() != 0))
+  if (isFullSet() || (isWrappedSet() && !getUpper().isNullValue()))
     return APInt::getMinValue(getBitWidth());
   return getLower();
 }
 
-/// getSignedMax - Return the largest signed value contained in the
-/// ConstantRange.
-///
 APInt ConstantRange::getSignedMax() const {
-  APInt SignedMax(APInt::getSignedMaxValue(getBitWidth()));
-  if (!isWrappedSet()) {
-    if (getLower().sle(getUpper() - 1))
-      return getUpper() - 1;
-    return SignedMax;
-  }
-  if (getLower().isNegative() == getUpper().isNegative())
-    return SignedMax;
+  if (isFullSet() || Lower.sgt(Upper))
+    return APInt::getSignedMaxValue(getBitWidth());
   return getUpper() - 1;
 }
 
-/// getSignedMin - Return the smallest signed value contained in the
-/// ConstantRange.
-///
 APInt ConstantRange::getSignedMin() const {
-  APInt SignedMin(APInt::getSignedMinValue(getBitWidth()));
-  if (!isWrappedSet()) {
-    if (getLower().sle(getUpper() - 1))
-      return getLower();
-    return SignedMin;
-  }
-  if ((getUpper() - 1).slt(getLower())) {
-    if (getUpper() != SignedMin)
-      return SignedMin;
-  }
+  if (isFullSet() || (Lower.sgt(Upper) && !getUpper().isMinSignedValue()))
+    return APInt::getSignedMinValue(getBitWidth());
   return getLower();
 }
 
-/// contains - Return true if the specified value is in the set.
-///
 bool ConstantRange::contains(const APInt &V) const {
   if (Lower == Upper)
     return isFullSet();
@@ -333,10 +313,6 @@ bool ConstantRange::contains(const APInt &V) const {
   return Lower.ule(V) || V.ult(Upper);
 }
 
-/// contains - Return true if the argument is a subset of this range.
-/// Two equal sets contain each other. The empty set contained by all other
-/// sets.
-///
 bool ConstantRange::contains(const ConstantRange &Other) const {
   if (isFullSet() || Other.isEmptySet()) return true;
   if (isEmptySet() || Other.isFullSet()) return false;
@@ -355,8 +331,6 @@ bool ConstantRange::contains(const ConstantRange &Other) const {
   return Other.getUpper().ule(Upper) && Lower.ule(Other.getLower());
 }
 
-/// subtract - Subtract the specified constant from the endpoints of this
-/// constant range.
 ConstantRange ConstantRange::subtract(const APInt &Val) const {
   assert(Val.getBitWidth() == getBitWidth() && "Wrong bit width");
   // If the set is empty or full, don't modify the endpoints.
@@ -365,17 +339,10 @@ ConstantRange ConstantRange::subtract(const APInt &Val) const {
   return ConstantRange(Lower - Val, Upper - Val);
 }
 
-/// \brief Subtract the specified range from this range (aka relative complement
-/// of the sets).
 ConstantRange ConstantRange::difference(const ConstantRange &CR) const {
   return intersectWith(CR.inverse());
 }
 
-/// intersectWith - Return the range that results from the intersection of this
-/// range with another range.  The resultant range is guaranteed to include all
-/// elements contained in both input ranges, and to have the smallest possible
-/// set size that does so.  Because there may be two intersections with the
-/// same set size, A.intersectWith(B) might not be equal to B.intersectWith(A).
 ConstantRange ConstantRange::intersectWith(const ConstantRange &CR) const {
   assert(getBitWidth() == CR.getBitWidth() && 
          "ConstantRange types don't agree!");
@@ -414,7 +381,7 @@ ConstantRange ConstantRange::intersectWith(const ConstantRange &CR) const {
       if (CR.Upper.ule(Lower))
         return ConstantRange(CR.Lower, Upper);
 
-      if (getSetSize().ult(CR.getSetSize()))
+      if (isSizeStrictlySmallerThan(CR))
         return *this;
       return CR;
     }
@@ -429,7 +396,7 @@ ConstantRange ConstantRange::intersectWith(const ConstantRange &CR) const {
 
   if (CR.Upper.ult(Upper)) {
     if (CR.Lower.ult(Upper)) {
-      if (getSetSize().ult(CR.getSetSize()))
+      if (isSizeStrictlySmallerThan(CR))
         return *this;
       return CR;
     }
@@ -445,18 +412,11 @@ ConstantRange ConstantRange::intersectWith(const ConstantRange &CR) const {
 
     return ConstantRange(CR.Lower, Upper);
   }
-  if (getSetSize().ult(CR.getSetSize()))
+  if (isSizeStrictlySmallerThan(CR))
     return *this;
   return CR;
 }
 
-
-/// unionWith - Return the range that results from the union of this range with
-/// another range.  The resultant range is guaranteed to include the elements of
-/// both sets, but may contain more.  For example, [3, 9) union [12,15) is
-/// [3, 15), which includes 9, 10, and 11, which were not included in either
-/// set before.
-///
 ConstantRange ConstantRange::unionWith(const ConstantRange &CR) const {
   assert(getBitWidth() == CR.getBitWidth() && 
          "ConstantRange types don't agree!");
@@ -475,16 +435,13 @@ ConstantRange ConstantRange::unionWith(const ConstantRange &CR) const {
       return ConstantRange(CR.Lower, Upper);
     }
 
-    APInt L = Lower, U = Upper;
-    if (CR.Lower.ult(L))
-      L = CR.Lower;
-    if ((CR.Upper - 1).ugt(U - 1))
-      U = CR.Upper;
+    APInt L = CR.Lower.ult(Lower) ? CR.Lower : Lower;
+    APInt U = (CR.Upper - 1).ugt(Upper - 1) ? CR.Upper : Upper;
 
-    if (L == 0 && U == 0)
+    if (L.isNullValue() && U.isNullValue())
       return ConstantRange(getBitWidth());
 
-    return ConstantRange(L, U);
+    return ConstantRange(std::move(L), std::move(U));
   }
 
   if (!CR.isWrappedSet()) {
@@ -525,13 +482,10 @@ ConstantRange ConstantRange::unionWith(const ConstantRange &CR) const {
   if (CR.Lower.ule(Upper) || Lower.ule(CR.Upper))
     return ConstantRange(getBitWidth());
 
-  APInt L = Lower, U = Upper;
-  if (CR.Upper.ugt(U))
-    U = CR.Upper;
-  if (CR.Lower.ult(L))
-    L = CR.Lower;
+  APInt L = CR.Lower.ult(Lower) ? CR.Lower : Lower;
+  APInt U = CR.Upper.ugt(Upper) ? CR.Upper : Upper;
 
-  return ConstantRange(L, U);
+  return ConstantRange(std::move(L), std::move(U));
 }
 
 ConstantRange ConstantRange::castOp(Instruction::CastOps CastOp,
@@ -558,14 +512,14 @@ ConstantRange ConstantRange::castOp(Instruction::CastOps CastOp,
     auto BW = getBitWidth();
     APInt Min = APInt::getMinValue(BW).zextOrSelf(ResultBitWidth);
     APInt Max = APInt::getMaxValue(BW).zextOrSelf(ResultBitWidth);
-    return ConstantRange(Min, Max);
+    return ConstantRange(std::move(Min), std::move(Max));
   }
   case Instruction::SIToFP: {
     // TODO: use input range if available
     auto BW = getBitWidth();
     APInt SMin = APInt::getSignedMinValue(BW).sextOrSelf(ResultBitWidth);
     APInt SMax = APInt::getSignedMaxValue(BW).sextOrSelf(ResultBitWidth);
-    return ConstantRange(SMin, SMax);
+    return ConstantRange(std::move(SMin), std::move(SMax));
   }
   case Instruction::FPTrunc:
   case Instruction::FPExt:
@@ -577,10 +531,6 @@ ConstantRange ConstantRange::castOp(Instruction::CastOps CastOp,
   };
 }
 
-/// zeroExtend - Return a new range in the specified integer type, which must
-/// be strictly larger than the current type.  The returned range will
-/// correspond to the possible range of values as if the source range had been
-/// zero extended.
 ConstantRange ConstantRange::zeroExtend(uint32_t DstTySize) const {
   if (isEmptySet()) return ConstantRange(DstTySize, /*isFullSet=*/false);
 
@@ -591,16 +541,13 @@ ConstantRange ConstantRange::zeroExtend(uint32_t DstTySize) const {
     APInt LowerExt(DstTySize, 0);
     if (!Upper) // special case: [X, 0) -- not really wrapping around
       LowerExt = Lower.zext(DstTySize);
-    return ConstantRange(LowerExt, APInt::getOneBitSet(DstTySize, SrcTySize));
+    return ConstantRange(std::move(LowerExt),
+                         APInt::getOneBitSet(DstTySize, SrcTySize));
   }
 
   return ConstantRange(Lower.zext(DstTySize), Upper.zext(DstTySize));
 }
 
-/// signExtend - Return a new range in the specified integer type, which must
-/// be strictly larger than the current type.  The returned range will
-/// correspond to the possible range of values as if the source range had been
-/// sign extended.
 ConstantRange ConstantRange::signExtend(uint32_t DstTySize) const {
   if (isEmptySet()) return ConstantRange(DstTySize, /*isFullSet=*/false);
 
@@ -619,10 +566,6 @@ ConstantRange ConstantRange::signExtend(uint32_t DstTySize) const {
   return ConstantRange(Lower.sext(DstTySize), Upper.sext(DstTySize));
 }
 
-/// truncate - Return a new range in the specified integer type, which must be
-/// strictly smaller than the current type.  The returned range will
-/// correspond to the possible range of values as if the source range had been
-/// truncated to the specified type.
 ConstantRange ConstantRange::truncate(uint32_t DstTySize) const {
   assert(getBitWidth() > DstTySize && "Not a value truncation");
   if (isEmptySet())
@@ -630,10 +573,6 @@ ConstantRange ConstantRange::truncate(uint32_t DstTySize) const {
   if (isFullSet())
     return ConstantRange(DstTySize, /*isFullSet=*/true);
 
-  APInt MaxValue = APInt::getMaxValue(DstTySize).zext(getBitWidth());
-  APInt MaxBitValue(getBitWidth(), 0);
-  MaxBitValue.setBit(DstTySize);
-
   APInt LowerDiv(Lower), UpperDiv(Upper);
   ConstantRange Union(DstTySize, /*isFullSet=*/false);
 
@@ -641,41 +580,46 @@ ConstantRange ConstantRange::truncate(uint32_t DstTySize) const {
   // We use the non-wrapped set code to analyze the [Lower, MaxValue) part, and
   // then we do the union with [MaxValue, Upper)
   if (isWrappedSet()) {
-    // If Upper is greater than Max Value, it covers the whole truncated range.
-    if (Upper.uge(MaxValue))
+    // If Upper is greater than or equal to MaxValue(DstTy), it covers the whole
+    // truncated range.
+    if (Upper.getActiveBits() > DstTySize ||
+        Upper.countTrailingOnes() == DstTySize)
       return ConstantRange(DstTySize, /*isFullSet=*/true);
 
     Union = ConstantRange(APInt::getMaxValue(DstTySize),Upper.trunc(DstTySize));
-    UpperDiv = APInt::getMaxValue(getBitWidth());
+    UpperDiv.setAllBits();
 
     // Union covers the MaxValue case, so return if the remaining range is just
-    // MaxValue.
+    // MaxValue(DstTy).
     if (LowerDiv == UpperDiv)
       return Union;
   }
 
   // Chop off the most significant bits that are past the destination bitwidth.
-  if (LowerDiv.uge(MaxValue)) {
-    APInt Div(getBitWidth(), 0);
-    APInt::udivrem(LowerDiv, MaxBitValue, Div, LowerDiv);
-    UpperDiv = UpperDiv - MaxBitValue * Div;
+  if (LowerDiv.getActiveBits() > DstTySize) {
+    // Mask to just the signficant bits and subtract from LowerDiv/UpperDiv.
+    APInt Adjust = LowerDiv & APInt::getBitsSetFrom(getBitWidth(), DstTySize);
+    LowerDiv -= Adjust;
+    UpperDiv -= Adjust;
   }
 
-  if (UpperDiv.ule(MaxValue))
+  unsigned UpperDivWidth = UpperDiv.getActiveBits();
+  if (UpperDivWidth <= DstTySize)
     return ConstantRange(LowerDiv.trunc(DstTySize),
                          UpperDiv.trunc(DstTySize)).unionWith(Union);
 
   // The truncated value wraps around. Check if we can do better than fullset.
-  APInt UpperModulo = UpperDiv - MaxBitValue;
-  if (UpperModulo.ult(LowerDiv))
-    return ConstantRange(LowerDiv.trunc(DstTySize),
-                         UpperModulo.trunc(DstTySize)).unionWith(Union);
+  if (UpperDivWidth == DstTySize + 1) {
+    // Clear the MSB so that UpperDiv wraps around.
+    UpperDiv.clearBit(DstTySize);
+    if (UpperDiv.ult(LowerDiv))
+      return ConstantRange(LowerDiv.trunc(DstTySize),
+                           UpperDiv.trunc(DstTySize)).unionWith(Union);
+  }
 
   return ConstantRange(DstTySize, /*isFullSet=*/true);
 }
 
-/// zextOrTrunc - make this range have the bit width given by \p DstTySize. The
-/// value is zero extended, truncated, or left alone to make it that width.
 ConstantRange ConstantRange::zextOrTrunc(uint32_t DstTySize) const {
   unsigned SrcTySize = getBitWidth();
   if (SrcTySize > DstTySize)
@@ -685,8 +629,6 @@ ConstantRange ConstantRange::zextOrTrunc(uint32_t DstTySize) const {
   return *this;
 }
 
-/// sextOrTrunc - make this range have the bit width given by \p DstTySize. The
-/// value is sign extended, truncated, or left alone to make it that width.
 ConstantRange ConstantRange::sextOrTrunc(uint32_t DstTySize) const {
   unsigned SrcTySize = getBitWidth();
   if (SrcTySize > DstTySize)
@@ -739,17 +681,16 @@ ConstantRange::add(const ConstantRange &Other) const {
   if (isFullSet() || Other.isFullSet())
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
 
-  APInt Spread_X = getSetSize(), Spread_Y = Other.getSetSize();
   APInt NewLower = getLower() + Other.getLower();
   APInt NewUpper = getUpper() + Other.getUpper() - 1;
   if (NewLower == NewUpper)
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
 
-  ConstantRange X = ConstantRange(NewLower, NewUpper);
-  if (X.getSetSize().ult(Spread_X) || X.getSetSize().ult(Spread_Y))
+  ConstantRange X = ConstantRange(std::move(NewLower), std::move(NewUpper));
+  if (X.isSizeStrictlySmallerThan(*this) ||
+      X.isSizeStrictlySmallerThan(Other))
     // We've wrapped, therefore, full set.
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
-
   return X;
 }
 
@@ -773,17 +714,16 @@ ConstantRange::sub(const ConstantRange &Other) const {
   if (isFullSet() || Other.isFullSet())
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
 
-  APInt Spread_X = getSetSize(), Spread_Y = Other.getSetSize();
   APInt NewLower = getLower() - Other.getUpper() + 1;
   APInt NewUpper = getUpper() - Other.getLower();
   if (NewLower == NewUpper)
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
 
-  ConstantRange X = ConstantRange(NewLower, NewUpper);
-  if (X.getSetSize().ult(Spread_X) || X.getSetSize().ult(Spread_Y))
+  ConstantRange X = ConstantRange(std::move(NewLower), std::move(NewUpper));
+  if (X.isSizeStrictlySmallerThan(*this) ||
+      X.isSizeStrictlySmallerThan(Other))
     // We've wrapped, therefore, full set.
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
-
   return X;
 }
 
@@ -817,7 +757,8 @@ ConstantRange::multiply(const ConstantRange &Other) const {
   // from one positive number to another which is as good as we can generate.
   // In this case, skip the extra work of generating signed ranges which aren't
   // going to be better than this range.
-  if (!UR.isWrappedSet() && UR.getLower().isNonNegative())
+  if (!UR.isWrappedSet() &&
+      (UR.getUpper().isNonNegative() || UR.getUpper().isMinSignedValue()))
     return UR;
 
   // Now the signed range. Because we could be dealing with negative numbers
@@ -837,7 +778,7 @@ ConstantRange::multiply(const ConstantRange &Other) const {
   ConstantRange Result_sext(std::min(L, Compare), std::max(L, Compare) + 1);
   ConstantRange SR = Result_sext.truncate(getBitWidth());
 
-  return UR.getSetSize().ult(SR.getSetSize()) ? UR : SR;
+  return UR.isSizeStrictlySmallerThan(SR) ? UR : SR;
 }
 
 ConstantRange
@@ -850,7 +791,7 @@ ConstantRange::smax(const ConstantRange &Other) const {
   APInt NewU = APIntOps::smax(getSignedMax(), Other.getSignedMax()) + 1;
   if (NewU == NewL)
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
-  return ConstantRange(NewL, NewU);
+  return ConstantRange(std::move(NewL), std::move(NewU));
 }
 
 ConstantRange
@@ -863,7 +804,7 @@ ConstantRange::umax(const ConstantRange &Other) const {
   APInt NewU = APIntOps::umax(getUnsignedMax(), Other.getUnsignedMax()) + 1;
   if (NewU == NewL)
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
-  return ConstantRange(NewL, NewU);
+  return ConstantRange(std::move(NewL), std::move(NewU));
 }
 
 ConstantRange
@@ -876,7 +817,7 @@ ConstantRange::smin(const ConstantRange &Other) const {
   APInt NewU = APIntOps::smin(getSignedMax(), Other.getSignedMax()) + 1;
   if (NewU == NewL)
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
-  return ConstantRange(NewL, NewU);
+  return ConstantRange(std::move(NewL), std::move(NewU));
 }
 
 ConstantRange
@@ -889,12 +830,12 @@ ConstantRange::umin(const ConstantRange &Other) const {
   APInt NewU = APIntOps::umin(getUnsignedMax(), Other.getUnsignedMax()) + 1;
   if (NewU == NewL)
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
-  return ConstantRange(NewL, NewU);
+  return ConstantRange(std::move(NewL), std::move(NewU));
 }
 
 ConstantRange
 ConstantRange::udiv(const ConstantRange &RHS) const {
-  if (isEmptySet() || RHS.isEmptySet() || RHS.getUnsignedMax() == 0)
+  if (isEmptySet() || RHS.isEmptySet() || RHS.getUnsignedMax().isNullValue())
     return ConstantRange(getBitWidth(), /*isFullSet=*/false);
   if (RHS.isFullSet())
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
@@ -902,13 +843,13 @@ ConstantRange::udiv(const ConstantRange &RHS) const {
   APInt Lower = getUnsignedMin().udiv(RHS.getUnsignedMax());
 
   APInt RHS_umin = RHS.getUnsignedMin();
-  if (RHS_umin == 0) {
+  if (RHS_umin.isNullValue()) {
     // We want the lowest value in RHS excluding zero. Usually that would be 1
     // except for a range in the form of [X, 1) in which case it would be X.
     if (RHS.getUpper() == 1)
       RHS_umin = RHS.getLower();
     else
-      RHS_umin = APInt(getBitWidth(), 1);
+      RHS_umin = 1;
   }
 
   APInt Upper = getUnsignedMax().udiv(RHS_umin) + 1;
@@ -918,7 +859,7 @@ ConstantRange::udiv(const ConstantRange &RHS) const {
   if (Lower == Upper)
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
 
-  return ConstantRange(Lower, Upper);
+  return ConstantRange(std::move(Lower), std::move(Upper));
 }
 
 ConstantRange
@@ -931,7 +872,7 @@ ConstantRange::binaryAnd(const ConstantRange &Other) const {
   APInt umin = APIntOps::umin(Other.getUnsignedMax(), getUnsignedMax());
   if (umin.isAllOnesValue())
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
-  return ConstantRange(APInt::getNullValue(getBitWidth()), umin + 1);
+  return ConstantRange(APInt::getNullValue(getBitWidth()), std::move(umin) + 1);
 }
 
 ConstantRange
@@ -942,9 +883,9 @@ ConstantRange::binaryOr(const ConstantRange &Other) const {
   // TODO: replace this with something less conservative
 
   APInt umax = APIntOps::umax(getUnsignedMin(), Other.getUnsignedMin());
-  if (umax.isMinValue())
+  if (umax.isNullValue())
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
-  return ConstantRange(umax, APInt::getNullValue(getBitWidth()));
+  return ConstantRange(std::move(umax), APInt::getNullValue(getBitWidth()));
 }
 
 ConstantRange
@@ -952,29 +893,33 @@ ConstantRange::shl(const ConstantRange &Other) const {
   if (isEmptySet() || Other.isEmptySet())
     return ConstantRange(getBitWidth(), /*isFullSet=*/false);
 
-  APInt min = getUnsignedMin().shl(Other.getUnsignedMin());
-  APInt max = getUnsignedMax().shl(Other.getUnsignedMax());
+  APInt max = getUnsignedMax();
+  APInt Other_umax = Other.getUnsignedMax();
 
-  // there's no overflow!
-  APInt Zeros(getBitWidth(), getUnsignedMax().countLeadingZeros());
-  if (Zeros.ugt(Other.getUnsignedMax()))
-    return ConstantRange(min, max + 1);
+  // there's overflow!
+  if (Other_umax.uge(max.countLeadingZeros()))
+    return ConstantRange(getBitWidth(), /*isFullSet=*/true);
 
   // FIXME: implement the other tricky cases
-  return ConstantRange(getBitWidth(), /*isFullSet=*/true);
+
+  APInt min = getUnsignedMin();
+  min <<= Other.getUnsignedMin();
+  max <<= Other_umax;
+
+  return ConstantRange(std::move(min), std::move(max) + 1);
 }
 
 ConstantRange
 ConstantRange::lshr(const ConstantRange &Other) const {
   if (isEmptySet() || Other.isEmptySet())
     return ConstantRange(getBitWidth(), /*isFullSet=*/false);
-  
-  APInt max = getUnsignedMax().lshr(Other.getUnsignedMin());
+
+  APInt max = getUnsignedMax().lshr(Other.getUnsignedMin()) + 1;
   APInt min = getUnsignedMin().lshr(Other.getUnsignedMax());
-  if (min == max + 1)
+  if (min == max)
     return ConstantRange(getBitWidth(), /*isFullSet=*/true);
 
-  return ConstantRange(min, max + 1);
+  return ConstantRange(std::move(min), std::move(max));
 }
 
 ConstantRange ConstantRange::inverse() const {
@@ -985,8 +930,6 @@ ConstantRange ConstantRange::inverse() const {
   return ConstantRange(Upper, Lower);
 }
 
-/// print - Print out the bounds to a stream...
-///
 void ConstantRange::print(raw_ostream &OS) const {
   if (isFullSet())
     OS << "full-set";
@@ -996,11 +939,11 @@ void ConstantRange::print(raw_ostream &OS) const {
     OS << "[" << Lower << "," << Upper << ")";
 }
 
-/// dump - Allow printing from a debugger easily...
-///
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
 LLVM_DUMP_METHOD void ConstantRange::dump() const {
   print(dbgs());
 }
+#endif
 
 ConstantRange llvm::getConstantRangeFromMetadata(const MDNode &Ranges) {
   const unsigned NumRanges = Ranges.getNumOperands() / 2;