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, 300 insertions, 111 deletions

diff --git a/contrib/llvm/lib/Analysis/LazyValueInfo.cpp b/contrib/llvm/lib/Analysis/LazyValueInfo.cpp
index d442310..102081e 100644
--- a/contrib/llvm/lib/Analysis/LazyValueInfo.cpp
+++ b/contrib/llvm/lib/Analysis/LazyValueInfo.cpp
@@ -19,6 +19,7 @@
 #include "llvm/Analysis/ConstantFolding.h"
 #include "llvm/Analysis/TargetLibraryInfo.h"
 #include "llvm/Analysis/ValueTracking.h"
+#include "llvm/IR/AssemblyAnnotationWriter.h"
 #include "llvm/IR/CFG.h"
 #include "llvm/IR/ConstantRange.h"
 #include "llvm/IR/Constants.h"
@@ -31,6 +32,7 @@
 #include "llvm/IR/PatternMatch.h"
 #include "llvm/IR/ValueHandle.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/FormattedStream.h"
 #include "llvm/Support/raw_ostream.h"
 #include <map>
 #include <stack>
@@ -39,6 +41,10 @@ using namespace PatternMatch;
 
 #define DEBUG_TYPE "lazy-value-info"
 
+// This is the number of worklist items we will process to try to discover an
+// answer for a given value.
+static const unsigned MaxProcessedPerValue = 500;
+
 char LazyValueInfoWrapperPass::ID = 0;
 INITIALIZE_PASS_BEGIN(LazyValueInfoWrapperPass, "lazy-value-info",
                 "Lazy Value Information Analysis", false, true)
@@ -136,7 +142,7 @@ public:
     return Val;
   }
 
-  ConstantRange getConstantRange() const {
+  const ConstantRange &getConstantRange() const {
     assert(isConstantRange() &&
            "Cannot get the constant-range of a non-constant-range!");
     return Range;
@@ -244,7 +250,7 @@ public:
     if (NewR.isFullSet())
       markOverdefined();
     else
-      markConstantRange(NewR);
+      markConstantRange(std::move(NewR));
   }
 };
 
@@ -296,7 +302,7 @@ static bool hasSingleValue(const LVILatticeVal &Val) {
 ///   contradictory.  If this happens, we return some valid lattice value so as
 ///   not confuse the rest of LVI.  Ideally, we'd always return Undefined, but
 ///   we do not make this guarantee.  TODO: This would be a useful enhancement.
-static LVILatticeVal intersect(LVILatticeVal A, LVILatticeVal B) {
+static LVILatticeVal intersect(const LVILatticeVal &A, const LVILatticeVal &B) {
   // Undefined is the strongest state.  It means the value is known to be along
   // an unreachable path.
   if (A.isUndefined())
@@ -366,22 +372,22 @@ namespace {
     struct ValueCacheEntryTy {
       ValueCacheEntryTy(Value *V, LazyValueInfoCache *P) : Handle(V, P) {}
       LVIValueHandle Handle;
-      SmallDenseMap<AssertingVH<BasicBlock>, LVILatticeVal, 4> BlockVals;
+      SmallDenseMap<PoisoningVH<BasicBlock>, LVILatticeVal, 4> BlockVals;
     };
 
-    /// This is all of the cached information for all values,
-    /// mapped from Value* to key information.
-    DenseMap<Value *, std::unique_ptr<ValueCacheEntryTy>> ValueCache;
-
     /// This tracks, on a per-block basis, the set of values that are
     /// over-defined at the end of that block.
-    typedef DenseMap<AssertingVH<BasicBlock>, SmallPtrSet<Value *, 4>>
+    typedef DenseMap<PoisoningVH<BasicBlock>, SmallPtrSet<Value *, 4>>
         OverDefinedCacheTy;
-    OverDefinedCacheTy OverDefinedCache;
-
     /// Keep track of all blocks that we have ever seen, so we
     /// don't spend time removing unused blocks from our caches.
-    DenseSet<AssertingVH<BasicBlock> > SeenBlocks;
+    DenseSet<PoisoningVH<BasicBlock> > SeenBlocks;
+
+    /// This is all of the cached information for all values,
+    /// mapped from Value* to key information.
+    DenseMap<Value *, std::unique_ptr<ValueCacheEntryTy>> ValueCache;
+    OverDefinedCacheTy OverDefinedCache;
+
 
   public:
     void insertResult(Value *Val, BasicBlock *BB, const LVILatticeVal &Result) {
@@ -459,15 +465,15 @@ namespace {
 }
 
 void LazyValueInfoCache::eraseValue(Value *V) {
-  SmallVector<AssertingVH<BasicBlock>, 4> ToErase;
-  for (auto &I : OverDefinedCache) {
-    SmallPtrSetImpl<Value *> &ValueSet = I.second;
+  for (auto I = OverDefinedCache.begin(), E = OverDefinedCache.end(); I != E;) {
+    // Copy and increment the iterator immediately so we can erase behind
+    // ourselves.
+    auto Iter = I++;
+    SmallPtrSetImpl<Value *> &ValueSet = Iter->second;
     ValueSet.erase(V);
     if (ValueSet.empty())
-      ToErase.push_back(I.first);
+      OverDefinedCache.erase(Iter);
   }
-  for (auto &BB : ToErase)
-    OverDefinedCache.erase(BB);
 
   ValueCache.erase(V);
 }
@@ -480,7 +486,7 @@ void LVIValueHandle::deleted() {
 
 void LazyValueInfoCache::eraseBlock(BasicBlock *BB) {
   // Shortcut if we have never seen this block.
-  DenseSet<AssertingVH<BasicBlock> >::iterator I = SeenBlocks.find(BB);
+  DenseSet<PoisoningVH<BasicBlock> >::iterator I = SeenBlocks.find(BB);
   if (I == SeenBlocks.end())
     return;
   SeenBlocks.erase(I);
@@ -551,6 +557,30 @@ void LazyValueInfoCache::threadEdgeImpl(BasicBlock *OldSucc,
   }
 }
 
+
+namespace {
+/// An assembly annotator class to print LazyValueCache information in
+/// comments.
+class LazyValueInfoImpl;
+class LazyValueInfoAnnotatedWriter : public AssemblyAnnotationWriter {
+  LazyValueInfoImpl *LVIImpl;
+  // While analyzing which blocks we can solve values for, we need the dominator
+  // information. Since this is an optional parameter in LVI, we require this
+  // DomTreeAnalysis pass in the printer pass, and pass the dominator
+  // tree to the LazyValueInfoAnnotatedWriter.
+  DominatorTree &DT;
+
+public:
+  LazyValueInfoAnnotatedWriter(LazyValueInfoImpl *L, DominatorTree &DTree)
+      : LVIImpl(L), DT(DTree) {}
+
+  virtual void emitBasicBlockStartAnnot(const BasicBlock *BB,
+                                        formatted_raw_ostream &OS);
+
+  virtual void emitInstructionAnnot(const Instruction *I,
+                                    formatted_raw_ostream &OS);
+};
+}
 namespace {
   // The actual implementation of the lazy analysis and update.  Note that the
   // inheritance from LazyValueInfoCache is intended to be temporary while
@@ -563,7 +593,7 @@ namespace {
     /// This stack holds the state of the value solver during a query.
     /// It basically emulates the callstack of the naive
     /// recursive value lookup process.
-    std::stack<std::pair<BasicBlock*, Value*> > BlockValueStack;
+    SmallVector<std::pair<BasicBlock*, Value*>, 8> BlockValueStack;
 
     /// Keeps track of which block-value pairs are in BlockValueStack.
     DenseSet<std::pair<BasicBlock*, Value*> > BlockValueSet;
@@ -576,7 +606,7 @@ namespace {
 
       DEBUG(dbgs() << "PUSH: " << *BV.second << " in " << BV.first->getName()
                    << "\n");
-      BlockValueStack.push(BV);
+      BlockValueStack.push_back(BV);
       return true;
     }
 
@@ -598,13 +628,13 @@ namespace {
   bool solveBlockValuePHINode(LVILatticeVal &BBLV, PHINode *PN, BasicBlock *BB);
   bool solveBlockValueSelect(LVILatticeVal &BBLV, SelectInst *S,
                              BasicBlock *BB);
-  bool solveBlockValueBinaryOp(LVILatticeVal &BBLV, Instruction *BBI,
+  bool solveBlockValueBinaryOp(LVILatticeVal &BBLV, BinaryOperator *BBI,
                                BasicBlock *BB);
-  bool solveBlockValueCast(LVILatticeVal &BBLV, Instruction *BBI,
+  bool solveBlockValueCast(LVILatticeVal &BBLV, CastInst *CI,
                            BasicBlock *BB);
   void intersectAssumeOrGuardBlockValueConstantRange(Value *Val,
                                                      LVILatticeVal &BBLV,
-                                              Instruction *BBI);
+                                                     Instruction *BBI);
 
   void solve();
 
@@ -629,6 +659,12 @@ namespace {
       TheCache.clear();
     }
 
+    /// Printing the LazyValueInfo Analysis.
+    void printLVI(Function &F, DominatorTree &DTree, raw_ostream &OS) {
+        LazyValueInfoAnnotatedWriter Writer(this, DTree);
+        F.print(OS, &Writer);
+    }
+
     /// This is part of the update interface to inform the cache
     /// that a block has been deleted.
     void eraseBlock(BasicBlock *BB) {
@@ -645,25 +681,52 @@ namespace {
   };
 } // end anonymous namespace
 
+
 void LazyValueInfoImpl::solve() {
+  SmallVector<std::pair<BasicBlock *, Value *>, 8> StartingStack(
+      BlockValueStack.begin(), BlockValueStack.end());
+
+  unsigned processedCount = 0;
   while (!BlockValueStack.empty()) {
-    std::pair<BasicBlock*, Value*> &e = BlockValueStack.top();
+    processedCount++;
+    // Abort if we have to process too many values to get a result for this one.
+    // Because of the design of the overdefined cache currently being per-block
+    // to avoid naming-related issues (IE it wants to try to give different
+    // results for the same name in different blocks), overdefined results don't
+    // get cached globally, which in turn means we will often try to rediscover
+    // the same overdefined result again and again.  Once something like
+    // PredicateInfo is used in LVI or CVP, we should be able to make the
+    // overdefined cache global, and remove this throttle.
+    if (processedCount > MaxProcessedPerValue) {
+      DEBUG(dbgs() << "Giving up on stack because we are getting too deep\n");
+      // Fill in the original values
+      while (!StartingStack.empty()) {
+        std::pair<BasicBlock *, Value *> &e = StartingStack.back();
+        TheCache.insertResult(e.second, e.first,
+                              LVILatticeVal::getOverdefined());
+        StartingStack.pop_back();
+      }
+      BlockValueSet.clear();
+      BlockValueStack.clear();
+      return;
+    }
+    std::pair<BasicBlock *, Value *> e = BlockValueStack.back();
     assert(BlockValueSet.count(e) && "Stack value should be in BlockValueSet!");
 
     if (solveBlockValue(e.second, e.first)) {
       // The work item was completely processed.
-      assert(BlockValueStack.top() == e && "Nothing should have been pushed!");
+      assert(BlockValueStack.back() == e && "Nothing should have been pushed!");
       assert(TheCache.hasCachedValueInfo(e.second, e.first) &&
              "Result should be in cache!");
 
       DEBUG(dbgs() << "POP " << *e.second << " in " << e.first->getName()
                    << " = " << TheCache.getCachedValueInfo(e.second, e.first) << "\n");
 
-      BlockValueStack.pop();
+      BlockValueStack.pop_back();
       BlockValueSet.erase(e);
     } else {
       // More work needs to be done before revisiting.
-      assert(BlockValueStack.top() != e && "Stack should have been pushed!");
+      assert(BlockValueStack.back() != e && "Stack should have been pushed!");
     }
   }
 }
@@ -743,7 +806,7 @@ bool LazyValueInfoImpl::solveBlockValueImpl(LVILatticeVal &Res,
   // that for all other pointer typed values, we terminate the search at the
   // definition.  We could easily extend this to look through geps, bitcasts,
   // and the like to prove non-nullness, but it's not clear that's worth it
-  // compile time wise.  The context-insensative value walk done inside
+  // compile time wise.  The context-insensitive value walk done inside
   // isKnownNonNull gets most of the profitable cases at much less expense.
   // This does mean that we have a sensativity to where the defining
   // instruction is placed, even if it could legally be hoisted much higher.
@@ -754,12 +817,12 @@ bool LazyValueInfoImpl::solveBlockValueImpl(LVILatticeVal &Res,
     return true;
   }
   if (BBI->getType()->isIntegerTy()) {
-    if (isa<CastInst>(BBI))
-      return solveBlockValueCast(Res, BBI, BB);
-    
+    if (auto *CI = dyn_cast<CastInst>(BBI))
+      return solveBlockValueCast(Res, CI, BB);
+
     BinaryOperator *BO = dyn_cast<BinaryOperator>(BBI);
     if (BO && isa<ConstantInt>(BO->getOperand(1)))
-      return solveBlockValueBinaryOp(Res, BBI, BB);
+      return solveBlockValueBinaryOp(Res, BO, BB);
   }
 
   DEBUG(dbgs() << " compute BB '" << BB->getName()
@@ -825,7 +888,7 @@ bool LazyValueInfoImpl::solveBlockValueNonLocal(LVILatticeVal &BBLV,
   // value is overdefined.
   if (BB == &BB->getParent()->getEntryBlock()) {
     assert(isa<Argument>(Val) && "Unknown live-in to the entry block");
-    // Bofore giving up, see if we can prove the pointer non-null local to
+    // Before giving up, see if we can prove the pointer non-null local to
     // this particular block.
     if (Val->getType()->isPointerTy() &&
         (isKnownNonNull(Val) || isObjectDereferencedInBlock(Val, BB))) {
@@ -839,13 +902,19 @@ bool LazyValueInfoImpl::solveBlockValueNonLocal(LVILatticeVal &BBLV,
   }
 
   // Loop over all of our predecessors, merging what we know from them into
-  // result.
-  bool EdgesMissing = false;
+  // result.  If we encounter an unexplored predecessor, we eagerly explore it
+  // in a depth first manner.  In practice, this has the effect of discovering
+  // paths we can't analyze eagerly without spending compile times analyzing
+  // other paths.  This heuristic benefits from the fact that predecessors are
+  // frequently arranged such that dominating ones come first and we quickly
+  // find a path to function entry.  TODO: We should consider explicitly
+  // canonicalizing to make this true rather than relying on this happy
+  // accident.  
   for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) {
     LVILatticeVal EdgeResult;
-    EdgesMissing |= !getEdgeValue(Val, *PI, BB, EdgeResult);
-    if (EdgesMissing)
-      continue;
+    if (!getEdgeValue(Val, *PI, BB, EdgeResult))
+      // Explore that input, then return here
+      return false;
 
     Result.mergeIn(EdgeResult, DL);
 
@@ -866,8 +935,6 @@ bool LazyValueInfoImpl::solveBlockValueNonLocal(LVILatticeVal &BBLV,
       return true;
     }
   }
-  if (EdgesMissing)
-    return false;
 
   // Return the merged value, which is more precise than 'overdefined'.
   assert(!Result.isOverdefined());
@@ -880,8 +947,8 @@ bool LazyValueInfoImpl::solveBlockValuePHINode(LVILatticeVal &BBLV,
   LVILatticeVal Result;  // Start Undefined.
 
   // Loop over all of our predecessors, merging what we know from them into
-  // result.
-  bool EdgesMissing = false;
+  // result.  See the comment about the chosen traversal order in
+  // solveBlockValueNonLocal; the same reasoning applies here.
   for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
     BasicBlock *PhiBB = PN->getIncomingBlock(i);
     Value *PhiVal = PN->getIncomingValue(i);
@@ -889,9 +956,9 @@ bool LazyValueInfoImpl::solveBlockValuePHINode(LVILatticeVal &BBLV,
     // Note that we can provide PN as the context value to getEdgeValue, even
     // though the results will be cached, because PN is the value being used as
     // the cache key in the caller.
-    EdgesMissing |= !getEdgeValue(PhiVal, PhiBB, BB, EdgeResult, PN);
-    if (EdgesMissing)
-      continue;
+    if (!getEdgeValue(PhiVal, PhiBB, BB, EdgeResult, PN))
+      // Explore that input, then return here
+      return false;
 
     Result.mergeIn(EdgeResult, DL);
 
@@ -905,8 +972,6 @@ bool LazyValueInfoImpl::solveBlockValuePHINode(LVILatticeVal &BBLV,
       return true;
     }
   }
-  if (EdgesMissing)
-    return false;
 
   // Return the merged value, which is more precise than 'overdefined'.
   assert(!Result.isOverdefined() && "Possible PHI in entry block?");
@@ -982,8 +1047,8 @@ bool LazyValueInfoImpl::solveBlockValueSelect(LVILatticeVal &BBLV,
   }
 
   if (TrueVal.isConstantRange() && FalseVal.isConstantRange()) {
-    ConstantRange TrueCR = TrueVal.getConstantRange();
-    ConstantRange FalseCR = FalseVal.getConstantRange();
+    const ConstantRange &TrueCR = TrueVal.getConstantRange();
+    const ConstantRange &FalseCR = FalseVal.getConstantRange();
     Value *LHS = nullptr;
     Value *RHS = nullptr;
     SelectPatternResult SPR = matchSelectPattern(SI, LHS, RHS);
@@ -1071,9 +1136,9 @@ bool LazyValueInfoImpl::solveBlockValueSelect(LVILatticeVal &BBLV,
 }
 
 bool LazyValueInfoImpl::solveBlockValueCast(LVILatticeVal &BBLV,
-                                             Instruction *BBI,
-                                             BasicBlock *BB) {
-  if (!BBI->getOperand(0)->getType()->isSized()) {
+                                            CastInst *CI,
+                                            BasicBlock *BB) {
+  if (!CI->getOperand(0)->getType()->isSized()) {
     // Without knowing how wide the input is, we can't analyze it in any useful
     // way.
     BBLV = LVILatticeVal::getOverdefined();
@@ -1083,7 +1148,7 @@ bool LazyValueInfoImpl::solveBlockValueCast(LVILatticeVal &BBLV,
   // Filter out casts we don't know how to reason about before attempting to
   // recurse on our operand.  This can cut a long search short if we know we're
   // not going to be able to get any useful information anways.
-  switch (BBI->getOpcode()) {
+  switch (CI->getOpcode()) {
   case Instruction::Trunc:
   case Instruction::SExt:
   case Instruction::ZExt:
@@ -1100,44 +1165,43 @@ bool LazyValueInfoImpl::solveBlockValueCast(LVILatticeVal &BBLV,
   // Figure out the range of the LHS.  If that fails, we still apply the
   // transfer rule on the full set since we may be able to locally infer
   // interesting facts.
-  if (!hasBlockValue(BBI->getOperand(0), BB))
-    if (pushBlockValue(std::make_pair(BB, BBI->getOperand(0))))
+  if (!hasBlockValue(CI->getOperand(0), BB))
+    if (pushBlockValue(std::make_pair(BB, CI->getOperand(0))))
       // More work to do before applying this transfer rule.
       return false;
 
   const unsigned OperandBitWidth =
-    DL.getTypeSizeInBits(BBI->getOperand(0)->getType());
+    DL.getTypeSizeInBits(CI->getOperand(0)->getType());
   ConstantRange LHSRange = ConstantRange(OperandBitWidth);
-  if (hasBlockValue(BBI->getOperand(0), BB)) {
-    LVILatticeVal LHSVal = getBlockValue(BBI->getOperand(0), BB);
-    intersectAssumeOrGuardBlockValueConstantRange(BBI->getOperand(0), LHSVal,
-                                                  BBI);
+  if (hasBlockValue(CI->getOperand(0), BB)) {
+    LVILatticeVal LHSVal = getBlockValue(CI->getOperand(0), BB);
+    intersectAssumeOrGuardBlockValueConstantRange(CI->getOperand(0), LHSVal,
+                                                  CI);
     if (LHSVal.isConstantRange())
       LHSRange = LHSVal.getConstantRange();
   }
 
-  const unsigned ResultBitWidth =
-    cast<IntegerType>(BBI->getType())->getBitWidth();
+  const unsigned ResultBitWidth = CI->getType()->getIntegerBitWidth();
 
   // NOTE: We're currently limited by the set of operations that ConstantRange
   // can evaluate symbolically.  Enhancing that set will allows us to analyze
   // more definitions.
-  auto CastOp = (Instruction::CastOps) BBI->getOpcode();
-  BBLV = LVILatticeVal::getRange(LHSRange.castOp(CastOp, ResultBitWidth));
+  BBLV = LVILatticeVal::getRange(LHSRange.castOp(CI->getOpcode(),
+                                                 ResultBitWidth));
   return true;
 }
 
 bool LazyValueInfoImpl::solveBlockValueBinaryOp(LVILatticeVal &BBLV,
-                                                 Instruction *BBI,
+                                                 BinaryOperator *BO,
                                                  BasicBlock *BB) {
 
-  assert(BBI->getOperand(0)->getType()->isSized() &&
+  assert(BO->getOperand(0)->getType()->isSized() &&
          "all operands to binary operators are sized");
 
   // Filter out operators we don't know how to reason about before attempting to
   // recurse on our operand(s).  This can cut a long search short if we know
-  // we're not going to be able to get any useful information anways.
-  switch (BBI->getOpcode()) {
+  // we're not going to be able to get any useful information anyways.
+  switch (BO->getOpcode()) {
   case Instruction::Add:
   case Instruction::Sub:
   case Instruction::Mul:
@@ -1159,29 +1223,29 @@ bool LazyValueInfoImpl::solveBlockValueBinaryOp(LVILatticeVal &BBLV,
   // Figure out the range of the LHS.  If that fails, use a conservative range,
   // but apply the transfer rule anyways.  This lets us pick up facts from
   // expressions like "and i32 (call i32 @foo()), 32"
-  if (!hasBlockValue(BBI->getOperand(0), BB))
-    if (pushBlockValue(std::make_pair(BB, BBI->getOperand(0))))
+  if (!hasBlockValue(BO->getOperand(0), BB))
+    if (pushBlockValue(std::make_pair(BB, BO->getOperand(0))))
       // More work to do before applying this transfer rule.
       return false;
 
   const unsigned OperandBitWidth =
-    DL.getTypeSizeInBits(BBI->getOperand(0)->getType());
+    DL.getTypeSizeInBits(BO->getOperand(0)->getType());
   ConstantRange LHSRange = ConstantRange(OperandBitWidth);
-  if (hasBlockValue(BBI->getOperand(0), BB)) {
-    LVILatticeVal LHSVal = getBlockValue(BBI->getOperand(0), BB);
-    intersectAssumeOrGuardBlockValueConstantRange(BBI->getOperand(0), LHSVal,
-                                                  BBI);
+  if (hasBlockValue(BO->getOperand(0), BB)) {
+    LVILatticeVal LHSVal = getBlockValue(BO->getOperand(0), BB);
+    intersectAssumeOrGuardBlockValueConstantRange(BO->getOperand(0), LHSVal,
+                                                  BO);
     if (LHSVal.isConstantRange())
       LHSRange = LHSVal.getConstantRange();
   }
 
-  ConstantInt *RHS = cast<ConstantInt>(BBI->getOperand(1));
+  ConstantInt *RHS = cast<ConstantInt>(BO->getOperand(1));
   ConstantRange RHSRange = ConstantRange(RHS->getValue());
 
   // NOTE: We're currently limited by the set of operations that ConstantRange
   // can evaluate symbolically.  Enhancing that set will allows us to analyze
   // more definitions.
-  auto BinOp = (Instruction::BinaryOps) BBI->getOpcode();
+  Instruction::BinaryOps BinOp = BO->getOpcode();
   BBLV = LVILatticeVal::getRange(LHSRange.binaryOp(BinOp, RHSRange));
   return true;
 }
@@ -1260,12 +1324,12 @@ getValueFromConditionImpl(Value *Val, Value *Cond, bool isTrueDest,
     return getValueFromICmpCondition(Val, ICI, isTrueDest);
 
   // Handle conditions in the form of (cond1 && cond2), we know that on the
-  // true dest path both of the conditions hold.
-  if (!isTrueDest)
-    return LVILatticeVal::getOverdefined();
-
+  // true dest path both of the conditions hold. Similarly for conditions of
+  // the form (cond1 || cond2), we know that on the false dest path neither
+  // condition holds.
   BinaryOperator *BO = dyn_cast<BinaryOperator>(Cond);
-  if (!BO || BO->getOpcode() != BinaryOperator::And)
+  if (!BO || (isTrueDest && BO->getOpcode() != BinaryOperator::And) ||
+             (!isTrueDest && BO->getOpcode() != BinaryOperator::Or))
     return LVILatticeVal::getOverdefined();
 
   auto RHS = getValueFromCondition(Val, BO->getOperand(0), isTrueDest, Visited);
@@ -1333,14 +1397,14 @@ static bool getEdgeValueLocal(Value *Val, BasicBlock *BBFrom,
     unsigned BitWidth = Val->getType()->getIntegerBitWidth();
     ConstantRange EdgesVals(BitWidth, DefaultCase/*isFullSet*/);
 
-    for (SwitchInst::CaseIt i : SI->cases()) {
-      ConstantRange EdgeVal(i.getCaseValue()->getValue());
+    for (auto Case : SI->cases()) {
+      ConstantRange EdgeVal(Case.getCaseValue()->getValue());
       if (DefaultCase) {
         // It is possible that the default destination is the destination of
         // some cases. There is no need to perform difference for those cases.
-        if (i.getCaseSuccessor() != BBTo)
+        if (Case.getCaseSuccessor() != BBTo)
           EdgesVals = EdgesVals.difference(EdgeVal);
-      } else if (i.getCaseSuccessor() == BBTo)
+      } else if (Case.getCaseSuccessor() == BBTo)
         EdgesVals = EdgesVals.unionWith(EdgeVal);
     }
     Result = LVILatticeVal::getRange(std::move(EdgesVals));
@@ -1352,8 +1416,8 @@ static bool getEdgeValueLocal(Value *Val, BasicBlock *BBFrom,
 /// \brief Compute the value of Val on the edge BBFrom -> BBTo or the value at
 /// the basic block if the edge does not constrain Val.
 bool LazyValueInfoImpl::getEdgeValue(Value *Val, BasicBlock *BBFrom,
-                                      BasicBlock *BBTo, LVILatticeVal &Result,
-                                      Instruction *CxtI) {
+                                     BasicBlock *BBTo, LVILatticeVal &Result,
+                                     Instruction *CxtI) {
   // If already a constant, there is nothing to compute.
   if (Constant *VC = dyn_cast<Constant>(Val)) {
     Result = LVILatticeVal::get(VC);
@@ -1503,6 +1567,18 @@ void LazyValueInfo::releaseMemory() {
   }
 }
 
+bool LazyValueInfo::invalidate(Function &F, const PreservedAnalyses &PA,
+                               FunctionAnalysisManager::Invalidator &Inv) {
+  // We need to invalidate if we have either failed to preserve this analyses
+  // result directly or if any of its dependencies have been invalidated.
+  auto PAC = PA.getChecker<LazyValueAnalysis>();
+  if (!(PAC.preserved() || PAC.preservedSet<AllAnalysesOn<Function>>()) ||
+      (DT && Inv.invalidate<DominatorTreeAnalysis>(F, PA)))
+    return true;
+
+  return false;
+}
+
 void LazyValueInfoWrapperPass::releaseMemory() { Info.releaseMemory(); }
 
 LazyValueInfo LazyValueAnalysis::run(Function &F, FunctionAnalysisManager &FAM) {
@@ -1510,7 +1586,7 @@ LazyValueInfo LazyValueAnalysis::run(Function &F, FunctionAnalysisManager &FAM)
   auto &TLI = FAM.getResult<TargetLibraryAnalysis>(F);
   auto *DT = FAM.getCachedResult<DominatorTreeAnalysis>(F);
 
-  return LazyValueInfo(&AC, &TLI, DT);
+  return LazyValueInfo(&AC, &F.getParent()->getDataLayout(), &TLI, DT);
 }
 
 /// Returns true if we can statically tell that this value will never be a
@@ -1540,7 +1616,7 @@ Constant *LazyValueInfo::getConstant(Value *V, BasicBlock *BB,
   if (Result.isConstant())
     return Result.getConstant();
   if (Result.isConstantRange()) {
-    ConstantRange CR = Result.getConstantRange();
+    const ConstantRange &CR = Result.getConstantRange();
     if (const APInt *SingleVal = CR.getSingleElement())
       return ConstantInt::get(V->getContext(), *SingleVal);
   }
@@ -1577,71 +1653,90 @@ Constant *LazyValueInfo::getConstantOnEdge(Value *V, BasicBlock *FromBB,
   if (Result.isConstant())
     return Result.getConstant();
   if (Result.isConstantRange()) {
-    ConstantRange CR = Result.getConstantRange();
+    const ConstantRange &CR = Result.getConstantRange();
     if (const APInt *SingleVal = CR.getSingleElement())
       return ConstantInt::get(V->getContext(), *SingleVal);
   }
   return nullptr;
 }
 
+ConstantRange LazyValueInfo::getConstantRangeOnEdge(Value *V,
+                                                    BasicBlock *FromBB,
+                                                    BasicBlock *ToBB,
+                                                    Instruction *CxtI) {
+  unsigned Width = V->getType()->getIntegerBitWidth();
+  const DataLayout &DL = FromBB->getModule()->getDataLayout();
+  LVILatticeVal Result =
+      getImpl(PImpl, AC, &DL, DT).getValueOnEdge(V, FromBB, ToBB, CxtI);
+
+  if (Result.isUndefined())
+    return ConstantRange(Width, /*isFullSet=*/false);
+  if (Result.isConstantRange())
+    return Result.getConstantRange();
+  // We represent ConstantInt constants as constant ranges but other kinds
+  // of integer constants, i.e. ConstantExpr will be tagged as constants
+  assert(!(Result.isConstant() && isa<ConstantInt>(Result.getConstant())) &&
+         "ConstantInt value must be represented as constantrange");
+  return ConstantRange(Width, /*isFullSet=*/true);
+}
+
 static LazyValueInfo::Tristate getPredicateResult(unsigned Pred, Constant *C,
-                                                  LVILatticeVal &Result,
+                                                  const LVILatticeVal &Val,
                                                   const DataLayout &DL,
                                                   TargetLibraryInfo *TLI) {
 
   // If we know the value is a constant, evaluate the conditional.
   Constant *Res = nullptr;
-  if (Result.isConstant()) {
-    Res = ConstantFoldCompareInstOperands(Pred, Result.getConstant(), C, DL,
-                                          TLI);
+  if (Val.isConstant()) {
+    Res = ConstantFoldCompareInstOperands(Pred, Val.getConstant(), C, DL, TLI);
     if (ConstantInt *ResCI = dyn_cast<ConstantInt>(Res))
       return ResCI->isZero() ? LazyValueInfo::False : LazyValueInfo::True;
     return LazyValueInfo::Unknown;
   }
 
-  if (Result.isConstantRange()) {
+  if (Val.isConstantRange()) {
     ConstantInt *CI = dyn_cast<ConstantInt>(C);
     if (!CI) return LazyValueInfo::Unknown;
 
-    ConstantRange CR = Result.getConstantRange();
+    const ConstantRange &CR = Val.getConstantRange();
     if (Pred == ICmpInst::ICMP_EQ) {
       if (!CR.contains(CI->getValue()))
         return LazyValueInfo::False;
 
-      if (CR.isSingleElement() && CR.contains(CI->getValue()))
+      if (CR.isSingleElement())
         return LazyValueInfo::True;
     } else if (Pred == ICmpInst::ICMP_NE) {
       if (!CR.contains(CI->getValue()))
         return LazyValueInfo::True;
 
-      if (CR.isSingleElement() && CR.contains(CI->getValue()))
+      if (CR.isSingleElement())
+        return LazyValueInfo::False;
+    } else {
+      // Handle more complex predicates.
+      ConstantRange TrueValues = ConstantRange::makeExactICmpRegion(
+          (ICmpInst::Predicate)Pred, CI->getValue());
+      if (TrueValues.contains(CR))
+        return LazyValueInfo::True;
+      if (TrueValues.inverse().contains(CR))
         return LazyValueInfo::False;
     }
-
-    // Handle more complex predicates.
-    ConstantRange TrueValues = ConstantRange::makeExactICmpRegion(
-        (ICmpInst::Predicate)Pred, CI->getValue());
-    if (TrueValues.contains(CR))
-      return LazyValueInfo::True;
-    if (TrueValues.inverse().contains(CR))
-      return LazyValueInfo::False;
     return LazyValueInfo::Unknown;
   }
 
-  if (Result.isNotConstant()) {
+  if (Val.isNotConstant()) {
     // If this is an equality comparison, we can try to fold it knowing that
     // "V != C1".
     if (Pred == ICmpInst::ICMP_EQ) {
       // !C1 == C -> false iff C1 == C.
       Res = ConstantFoldCompareInstOperands(ICmpInst::ICMP_NE,
-                                            Result.getNotConstant(), C, DL,
+                                            Val.getNotConstant(), C, DL,
                                             TLI);
       if (Res->isNullValue())
         return LazyValueInfo::False;
     } else if (Pred == ICmpInst::ICMP_NE) {
       // !C1 != C -> true iff C1 == C.
       Res = ConstantFoldCompareInstOperands(ICmpInst::ICMP_NE,
-                                            Result.getNotConstant(), C, DL,
+                                            Val.getNotConstant(), C, DL,
                                             TLI);
       if (Res->isNullValue())
         return LazyValueInfo::True;
@@ -1780,3 +1875,97 @@ void LazyValueInfo::eraseBlock(BasicBlock *BB) {
     getImpl(PImpl, AC, &DL, DT).eraseBlock(BB);
   }
 }
+
+
+void LazyValueInfo::printLVI(Function &F, DominatorTree &DTree, raw_ostream &OS) {
+  if (PImpl) {
+    getImpl(PImpl, AC, DL, DT).printLVI(F, DTree, OS);
+  }
+}
+
+// Print the LVI for the function arguments at the start of each basic block.
+void LazyValueInfoAnnotatedWriter::emitBasicBlockStartAnnot(
+    const BasicBlock *BB, formatted_raw_ostream &OS) {
+  // Find if there are latticevalues defined for arguments of the function.
+  auto *F = BB->getParent();
+  for (auto &Arg : F->args()) {
+    LVILatticeVal Result = LVIImpl->getValueInBlock(
+        const_cast<Argument *>(&Arg), const_cast<BasicBlock *>(BB));
+    if (Result.isUndefined())
+      continue;
+    OS << "; LatticeVal for: '" << Arg << "' is: " << Result << "\n";
+  }
+}
+
+// This function prints the LVI analysis for the instruction I at the beginning
+// of various basic blocks. It relies on calculated values that are stored in
+// the LazyValueInfoCache, and in the absence of cached values, recalculte the
+// LazyValueInfo for `I`, and print that info.
+void LazyValueInfoAnnotatedWriter::emitInstructionAnnot(
+    const Instruction *I, formatted_raw_ostream &OS) {
+
+  auto *ParentBB = I->getParent();
+  SmallPtrSet<const BasicBlock*, 16> BlocksContainingLVI;
+  // We can generate (solve) LVI values only for blocks that are dominated by
+  // the I's parent. However, to avoid generating LVI for all dominating blocks,
+  // that contain redundant/uninteresting information, we print LVI for
+  // blocks that may use this LVI information (such as immediate successor
+  // blocks, and blocks that contain uses of `I`).
+  auto printResult = [&](const BasicBlock *BB) {
+    if (!BlocksContainingLVI.insert(BB).second)
+      return;
+    LVILatticeVal Result = LVIImpl->getValueInBlock(
+        const_cast<Instruction *>(I), const_cast<BasicBlock *>(BB));
+      OS << "; LatticeVal for: '" << *I << "' in BB: '";
+      BB->printAsOperand(OS, false);
+      OS << "' is: " << Result << "\n";
+  };
+
+  printResult(ParentBB);
+  // Print the LVI analysis results for the the immediate successor blocks, that
+  // are dominated by `ParentBB`.
+  for (auto *BBSucc : successors(ParentBB))
+    if (DT.dominates(ParentBB, BBSucc))
+      printResult(BBSucc);
+
+  // Print LVI in blocks where `I` is used.
+  for (auto *U : I->users())
+    if (auto *UseI = dyn_cast<Instruction>(U))
+      if (!isa<PHINode>(UseI) || DT.dominates(ParentBB, UseI->getParent()))
+        printResult(UseI->getParent());
+
+}
+
+namespace {
+// Printer class for LazyValueInfo results.
+class LazyValueInfoPrinter : public FunctionPass {
+public:
+  static char ID; // Pass identification, replacement for typeid
+  LazyValueInfoPrinter() : FunctionPass(ID) {
+    initializeLazyValueInfoPrinterPass(*PassRegistry::getPassRegistry());
+  }
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override {
+    AU.setPreservesAll();
+    AU.addRequired<LazyValueInfoWrapperPass>();
+    AU.addRequired<DominatorTreeWrapperPass>();
+  }
+
+  // Get the mandatory dominator tree analysis and pass this in to the
+  // LVIPrinter. We cannot rely on the LVI's DT, since it's optional.
+  bool runOnFunction(Function &F) override {
+    dbgs() << "LVI for function '" << F.getName() << "':\n";
+    auto &LVI = getAnalysis<LazyValueInfoWrapperPass>().getLVI();
+    auto &DTree = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
+    LVI.printLVI(F, DTree, dbgs());
+    return false;
+  }
+};
+}
+
+char LazyValueInfoPrinter::ID = 0;
+INITIALIZE_PASS_BEGIN(LazyValueInfoPrinter, "print-lazy-value-info",
+                "Lazy Value Info Printer Pass", false, false)
+INITIALIZE_PASS_DEPENDENCY(LazyValueInfoWrapperPass)
+INITIALIZE_PASS_END(LazyValueInfoPrinter, "print-lazy-value-info",
+                "Lazy Value Info Printer Pass", false, false)