am 31675153: Merge branch \'upstream\' into merge_2

* commit '31675153bd2d7617db8cb6aeb58054934c7b9f73': (542 commits)
  MaximumSpanningTree::EdgeWeightCompare: Make this comparator actually be a strict weak ordering, and don't pass possibly-null pointers to dyn_cast.
  Fix misaligned access in MachO object file reader: despite containing an int64_t, Symbol64TableEntry is actually only stored with 4-byte alignment within the file.
  Fix unaligned memory accesses when performing relocations in X86 JIT. There's no cost to using memcpy here: the fixed code is optimized by LLVM to perfect machine code.
  Don't pass a null pointer to cast<> in its unit tests.
  Don't bind a reference to a dereferenced null pointer (for return value of WeakVH::operator*).
  [ms-inline asm] Do not report a Parser error when matching inline assembly.
  Ignore the documentation-suggested location for compile_commands.json
  The presence of the empty file "foo" unfortunately does not improve LLVM in any way.
  Remove unnecessary cast that was also unnecessarily casting away constness.
  Provide a portability macro for __builtin_trap.
  Fix macros arguments with an underscore, dot or dollar in them. This is based on a patch by Andy/PaX. I added the support for dot and dollar.
  [ms-inline asm] Expose the ErrorInfo from the MatchInstructionImpl.  In general, this is the index of the operand that failed to match.
  Formatting.  No functional change.
  Make the wording in of the "expected identifier" error in the .macro directive consistent with the other "expected identifier" errors. Extracted from the Andy/PaX patch. I added the test.
  Pacify PVS-Studio by changing the type rather than doing a cast, a tweak suggested by David Blaikie.
  Add support for the --param ssp-buffer-size= driver option. PR9673
  Use typedefs. Fix indentation. Extracted from the Andy/PaX patch.
  Remove unused variable. Extracted from the Andy/PaX patch.
  Fix typo. Extracted from the Andy/PaX patch.
  MCJIT: Tidy up the constructor.
  ...

1 files changed, 30 insertions, 2 deletions

diff --git a/lib/Analysis/BranchProbabilityInfo.cpp b/lib/Analysis/BranchProbabilityInfo.cpp
index 2730ce6..b255ce6 100644
--- a/lib/Analysis/BranchProbabilityInfo.cpp
+++ b/lib/Analysis/BranchProbabilityInfo.cpp
@@ -1,4 +1,4 @@
-//===-- BranchProbabilityInfo.cpp - Branch Probability Analysis -*- C++ -*-===//
+//===-- BranchProbabilityInfo.cpp - Branch Probability Analysis -----------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -78,6 +78,19 @@ static const uint32_t ZH_NONTAKEN_WEIGHT = 12;
 static const uint32_t FPH_TAKEN_WEIGHT = 20;
 static const uint32_t FPH_NONTAKEN_WEIGHT = 12;
 
+/// \brief Invoke-terminating normal branch taken weight
+///
+/// This is the weight for branching to the normal destination of an invoke
+/// instruction. We expect this to happen most of the time. Set the weight to an
+/// absurdly high value so that nested loops subsume it.
+static const uint32_t IH_TAKEN_WEIGHT = 1024 * 1024 - 1;
+
+/// \brief Invoke-terminating normal branch not-taken weight.
+///
+/// This is the weight for branching to the unwind destination of an invoke
+/// instruction. This is essentially never taken.
+static const uint32_t IH_NONTAKEN_WEIGHT = 1;
+
 // Standard weight value. Used when none of the heuristics set weight for
 // the edge.
 static const uint32_t NORMAL_WEIGHT = 16;
@@ -371,6 +384,19 @@ bool BranchProbabilityInfo::calcFloatingPointHeuristics(BasicBlock *BB) {
   return true;
 }
 
+bool BranchProbabilityInfo::calcInvokeHeuristics(BasicBlock *BB) {
+  InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator());
+  if (!II)
+    return false;
+
+  BasicBlock *Normal = II->getNormalDest();
+  BasicBlock *Unwind = II->getUnwindDest();
+
+  setEdgeWeight(BB, Normal, IH_TAKEN_WEIGHT);
+  setEdgeWeight(BB, Unwind, IH_NONTAKEN_WEIGHT);
+  return true;
+}
+
 void BranchProbabilityInfo::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequired<LoopInfo>();
   AU.setPreservesAll();
@@ -397,7 +423,9 @@ bool BranchProbabilityInfo::runOnFunction(Function &F) {
       continue;
     if (calcZeroHeuristics(*I))
       continue;
-    calcFloatingPointHeuristics(*I);
+    if (calcFloatingPointHeuristics(*I))
+      continue;
+    calcInvokeHeuristics(*I);
   }
 
   PostDominatedByUnreachable.clear();