Update LLVM for 3.5 rebase (r209712).

Change-Id: I149556c940fb7dc92d075273c87ff584f400941f

4 files changed, 70 insertions, 54 deletions

diff --git a/lib/Analysis/IPA/CallGraph.cpp b/lib/Analysis/IPA/CallGraph.cpp
index f43675b..caec253 100644
--- a/lib/Analysis/IPA/CallGraph.cpp
+++ b/lib/Analysis/IPA/CallGraph.cpp
@@ -21,14 +21,14 @@ using namespace llvm;
 //
 
 CallGraph::CallGraph(Module &M)
-    : M(M), Root(0), ExternalCallingNode(getOrInsertFunction(0)),
-      CallsExternalNode(new CallGraphNode(0)) {
+    : M(M), Root(nullptr), ExternalCallingNode(getOrInsertFunction(nullptr)),
+      CallsExternalNode(new CallGraphNode(nullptr)) {
   // Add every function to the call graph.
   for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
     addToCallGraph(I);
 
   // If we didn't find a main function, use the external call graph node
-  if (Root == 0)
+  if (!Root)
     Root = ExternalCallingNode;
 }
 
@@ -210,7 +210,7 @@ void CallGraphNode::removeOneAbstractEdgeTo(CallGraphNode *Callee) {
   for (CalledFunctionsVector::iterator I = CalledFunctions.begin(); ; ++I) {
     assert(I != CalledFunctions.end() && "Cannot find callee to remove!");
     CallRecord &CR = *I;
-    if (CR.second == Callee && CR.first == 0) {
+    if (CR.second == Callee && CR.first == nullptr) {
       Callee->DropRef();
       *I = CalledFunctions.back();
       CalledFunctions.pop_back();
@@ -267,7 +267,7 @@ INITIALIZE_PASS(CallGraphWrapperPass, "basiccg", "CallGraph Construction",
 
 char CallGraphWrapperPass::ID = 0;
 
-void CallGraphWrapperPass::releaseMemory() { G.reset(0); }
+void CallGraphWrapperPass::releaseMemory() { G.reset(nullptr); }
 
 void CallGraphWrapperPass::print(raw_ostream &OS, const Module *) const {
   if (!G) {
@@ -280,7 +280,7 @@ void CallGraphWrapperPass::print(raw_ostream &OS, const Module *) const {
 }
 
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
-void CallGraphWrapperPass::dump() const { print(dbgs(), 0); }
+void CallGraphWrapperPass::dump() const { print(dbgs(), nullptr); }
 #endif
 
 // Enuse that users of CallGraph.h also link with this file
diff --git a/lib/Analysis/IPA/CallGraphSCCPass.cpp b/lib/Analysis/IPA/CallGraphSCCPass.cpp
index aafc085..bfab744 100644
--- a/lib/Analysis/IPA/CallGraphSCCPass.cpp
+++ b/lib/Analysis/IPA/CallGraphSCCPass.cpp
@@ -15,7 +15,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "cgscc-passmgr"
 #include "llvm/Analysis/CallGraphSCCPass.h"
 #include "llvm/ADT/SCCIterator.h"
 #include "llvm/ADT/Statistic.h"
@@ -23,12 +22,15 @@
 #include "llvm/IR/Function.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/LegacyPassManagers.h"
+#include "llvm/IR/LLVMContext.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/Timer.h"
 #include "llvm/Support/raw_ostream.h"
 using namespace llvm;
 
+#define DEBUG_TYPE "cgscc-passmgr"
+
 static cl::opt<unsigned> 
 MaxIterations("max-cg-scc-iterations", cl::ReallyHidden, cl::init(4));
 
@@ -112,7 +114,7 @@ bool CGPassManager::RunPassOnSCC(Pass *P, CallGraphSCC &CurSCC,
   bool Changed = false;
   PMDataManager *PM = P->getAsPMDataManager();
 
-  if (PM == 0) {
+  if (!PM) {
     CallGraphSCCPass *CGSP = (CallGraphSCCPass*)P;
     if (!CallGraphUpToDate) {
       DevirtualizedCall |= RefreshCallGraph(CurSCC, CG, false);
@@ -144,8 +146,11 @@ bool CGPassManager::RunPassOnSCC(Pass *P, CallGraphSCC &CurSCC,
        I != E; ++I) {
     if (Function *F = (*I)->getFunction()) {
       dumpPassInfo(P, EXECUTION_MSG, ON_FUNCTION_MSG, F->getName());
-      TimeRegion PassTimer(getPassTimer(FPP));
-      Changed |= FPP->runOnFunction(*F);
+      {
+        TimeRegion PassTimer(getPassTimer(FPP));
+        Changed |= FPP->runOnFunction(*F);
+      }
+      F->getContext().yield();
     }
   }
   
@@ -190,7 +195,7 @@ bool CGPassManager::RefreshCallGraph(CallGraphSCC &CurSCC,
        SCCIdx != E; ++SCCIdx, ++FunctionNo) {
     CallGraphNode *CGN = *SCCIdx;
     Function *F = CGN->getFunction();
-    if (F == 0 || F->isDeclaration()) continue;
+    if (!F || F->isDeclaration()) continue;
     
     // Walk the function body looking for call sites.  Sync up the call sites in
     // CGN with those actually in the function.
@@ -203,7 +208,7 @@ bool CGPassManager::RefreshCallGraph(CallGraphSCC &CurSCC,
     for (CallGraphNode::iterator I = CGN->begin(), E = CGN->end(); I != E; ) {
       // If this call site is null, then the function pass deleted the call
       // entirely and the WeakVH nulled it out.  
-      if (I->first == 0 ||
+      if (!I->first ||
           // If we've already seen this call site, then the FunctionPass RAUW'd
           // one call with another, which resulted in two "uses" in the edge
           // list of the same call.
@@ -217,7 +222,7 @@ bool CGPassManager::RefreshCallGraph(CallGraphSCC &CurSCC,
                "CallGraphSCCPass did not update the CallGraph correctly!");
         
         // If this was an indirect call site, count it.
-        if (I->second->getFunction() == 0)
+        if (!I->second->getFunction())
           ++NumIndirectRemoved;
         else 
           ++NumDirectRemoved;
@@ -273,7 +278,7 @@ bool CGPassManager::RefreshCallGraph(CallGraphSCC &CurSCC,
           // site could be turned direct), don't reject it in checking mode, and
           // don't tweak it to be more precise.
           if (CheckingMode && CS.getCalledFunction() &&
-              ExistingNode->getFunction() == 0)
+              ExistingNode->getFunction() == nullptr)
             continue;
           
           assert(!CheckingMode &&
@@ -286,7 +291,7 @@ bool CGPassManager::RefreshCallGraph(CallGraphSCC &CurSCC,
             CalleeNode = CG.getOrInsertFunction(Callee);
             // Keep track of whether we turned an indirect call into a direct
             // one.
-            if (ExistingNode->getFunction() == 0) {
+            if (!ExistingNode->getFunction()) {
               DevirtualizedCall = true;
               DEBUG(dbgs() << "  CGSCCPASSMGR: Devirtualized call to '"
                            << Callee->getName() << "'\n");
@@ -434,8 +439,8 @@ bool CGPassManager::runOnModule(Module &M) {
   while (!CGI.isAtEnd()) {
     // Copy the current SCC and increment past it so that the pass can hack
     // on the SCC if it wants to without invalidating our iterator.
-    std::vector<CallGraphNode*> &NodeVec = *CGI;
-    CurSCC.initialize(&NodeVec[0], &NodeVec[0]+NodeVec.size());
+    const std::vector<CallGraphNode *> &NodeVec = *CGI;
+    CurSCC.initialize(NodeVec.data(), NodeVec.data() + NodeVec.size());
     ++CGI;
     
     // At the top level, we run all the passes in this pass manager on the
diff --git a/lib/Analysis/IPA/GlobalsModRef.cpp b/lib/Analysis/IPA/GlobalsModRef.cpp
index f4097e4..607c068 100644
--- a/lib/Analysis/IPA/GlobalsModRef.cpp
+++ b/lib/Analysis/IPA/GlobalsModRef.cpp
@@ -14,7 +14,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "globalsmodref-aa"
 #include "llvm/Analysis/Passes.h"
 #include "llvm/ADT/SCCIterator.h"
 #include "llvm/ADT/Statistic.h"
@@ -33,6 +32,8 @@
 #include <set>
 using namespace llvm;
 
+#define DEBUG_TYPE "globalsmodref-aa"
+
 STATISTIC(NumNonAddrTakenGlobalVars,
           "Number of global vars without address taken");
 STATISTIC(NumNonAddrTakenFunctions,"Number of functions without address taken");
@@ -177,14 +178,14 @@ namespace {
         FunctionInfo.find(F);
       if (I != FunctionInfo.end())
         return &I->second;
-      return 0;
+      return nullptr;
     }
 
     void AnalyzeGlobals(Module &M);
     void AnalyzeCallGraph(CallGraph &CG, Module &M);
     bool AnalyzeUsesOfPointer(Value *V, std::vector<Function*> &Readers,
                               std::vector<Function*> &Writers,
-                              GlobalValue *OkayStoreDest = 0);
+                              GlobalValue *OkayStoreDest = nullptr);
     bool AnalyzeIndirectGlobalMemory(GlobalValue *GV);
   };
 }
@@ -358,7 +359,7 @@ void GlobalsModRef::AnalyzeCallGraph(CallGraph &CG, Module &M) {
   // We do a bottom-up SCC traversal of the call graph.  In other words, we
   // visit all callees before callers (leaf-first).
   for (scc_iterator<CallGraph*> I = scc_begin(&CG); !I.isAtEnd(); ++I) {
-    std::vector<CallGraphNode *> &SCC = *I;
+    const std::vector<CallGraphNode *> &SCC = *I;
     assert(!SCC.empty() && "SCC with no functions?");
 
     if (!SCC[0]->getFunction()) {
@@ -410,10 +411,8 @@ void GlobalsModRef::AnalyzeCallGraph(CallGraph &CG, Module &M) {
             FunctionEffect |= CalleeFR->FunctionEffect;
 
             // Incorporate callee's effects on globals into our info.
-            for (std::map<const GlobalValue*, unsigned>::iterator GI =
-                   CalleeFR->GlobalInfo.begin(), E = CalleeFR->GlobalInfo.end();
-                 GI != E; ++GI)
-              FR.GlobalInfo[GI->first] |= GI->second;
+            for (const auto &G : CalleeFR->GlobalInfo)
+              FR.GlobalInfo[G.first] |= G.second;
             FR.MayReadAnyGlobal |= CalleeFR->MayReadAnyGlobal;
           } else {
             // Can't say anything about it.  However, if it is inside our SCC,
@@ -492,8 +491,8 @@ GlobalsModRef::alias(const Location &LocA,
   if (GV1 || GV2) {
     // If the global's address is taken, pretend we don't know it's a pointer to
     // the global.
-    if (GV1 && !NonAddressTakenGlobals.count(GV1)) GV1 = 0;
-    if (GV2 && !NonAddressTakenGlobals.count(GV2)) GV2 = 0;
+    if (GV1 && !NonAddressTakenGlobals.count(GV1)) GV1 = nullptr;
+    if (GV2 && !NonAddressTakenGlobals.count(GV2)) GV2 = nullptr;
 
     // If the two pointers are derived from two different non-addr-taken
     // globals, or if one is and the other isn't, we know these can't alias.
@@ -507,7 +506,7 @@ GlobalsModRef::alias(const Location &LocA,
   // These pointers may be based on the memory owned by an indirect global.  If
   // so, we may be able to handle this.  First check to see if the base pointer
   // is a direct load from an indirect global.
-  GV1 = GV2 = 0;
+  GV1 = GV2 = nullptr;
   if (const LoadInst *LI = dyn_cast<LoadInst>(UV1))
     if (GlobalVariable *GV = dyn_cast<GlobalVariable>(LI->getOperand(0)))
       if (IndirectGlobals.count(GV))
diff --git a/lib/Analysis/IPA/InlineCost.cpp b/lib/Analysis/IPA/InlineCost.cpp
index 8dafc1c..66f3f8e 100644
--- a/lib/Analysis/IPA/InlineCost.cpp
+++ b/lib/Analysis/IPA/InlineCost.cpp
@@ -11,7 +11,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "inline-cost"
 #include "llvm/Analysis/InlineCost.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SetVector.h"
@@ -34,6 +33,8 @@
 
 using namespace llvm;
 
+#define DEBUG_TYPE "inline-cost"
+
 STATISTIC(NumCallsAnalyzed, "Number of call sites analyzed");
 
 namespace {
@@ -97,9 +98,6 @@ class CallAnalyzer : public InstVisitor<CallAnalyzer, bool> {
   void disableSROA(Value *V);
   void accumulateSROACost(DenseMap<Value *, int>::iterator CostIt,
                           int InstructionCost);
-  bool handleSROACandidate(bool IsSROAValid,
-                           DenseMap<Value *, int>::iterator CostIt,
-                           int InstructionCost);
   bool isGEPOffsetConstant(GetElementPtrInst &GEP);
   bool accumulateGEPOffset(GEPOperator &GEP, APInt &Offset);
   bool simplifyCallSite(Function *F, CallSite CS);
@@ -225,21 +223,6 @@ void CallAnalyzer::accumulateSROACost(DenseMap<Value *, int>::iterator CostIt,
   SROACostSavings += InstructionCost;
 }
 
-/// \brief Helper for the common pattern of handling a SROA candidate.
-/// Either accumulates the cost savings if the SROA remains valid, or disables
-/// SROA for the candidate.
-bool CallAnalyzer::handleSROACandidate(bool IsSROAValid,
-                                       DenseMap<Value *, int>::iterator CostIt,
-                                       int InstructionCost) {
-  if (IsSROAValid) {
-    accumulateSROACost(CostIt, InstructionCost);
-    return true;
-  }
-
-  disableSROA(CostIt);
-  return false;
-}
-
 /// \brief Check whether a GEP's indices are all constant.
 ///
 /// Respects any simplified values known during the analysis of this callsite.
@@ -287,8 +270,17 @@ bool CallAnalyzer::accumulateGEPOffset(GEPOperator &GEP, APInt &Offset) {
 }
 
 bool CallAnalyzer::visitAlloca(AllocaInst &I) {
-  // FIXME: Check whether inlining will turn a dynamic alloca into a static
+  // Check whether inlining will turn a dynamic alloca into a static
   // alloca, and handle that case.
+  if (I.isArrayAllocation()) {
+    if (Constant *Size = SimplifiedValues.lookup(I.getArraySize())) {
+      ConstantInt *AllocSize = dyn_cast<ConstantInt>(Size);
+      assert(AllocSize && "Allocation size not a constant int?");
+      Type *Ty = I.getAllocatedType();
+      AllocatedSize += Ty->getPrimitiveSizeInBits() * AllocSize->getZExtValue();
+      return Base::visitAlloca(I);
+    }
+  }
 
   // Accumulate the allocated size.
   if (I.isStaticAlloca()) {
@@ -816,9 +808,29 @@ bool CallAnalyzer::visitBranchInst(BranchInst &BI) {
 bool CallAnalyzer::visitSwitchInst(SwitchInst &SI) {
   // We model unconditional switches as free, see the comments on handling
   // branches.
-  return isa<ConstantInt>(SI.getCondition()) ||
-         dyn_cast_or_null<ConstantInt>(
-             SimplifiedValues.lookup(SI.getCondition()));
+  if (isa<ConstantInt>(SI.getCondition()))
+    return true;
+  if (Value *V = SimplifiedValues.lookup(SI.getCondition()))
+    if (isa<ConstantInt>(V))
+      return true;
+
+  // Otherwise, we need to accumulate a cost proportional to the number of
+  // distinct successor blocks. This fan-out in the CFG cannot be represented
+  // for free even if we can represent the core switch as a jumptable that
+  // takes a single instruction.
+  //
+  // NB: We convert large switches which are just used to initialize large phi
+  // nodes to lookup tables instead in simplify-cfg, so this shouldn't prevent
+  // inlining those. It will prevent inlining in cases where the optimization
+  // does not (yet) fire.
+  SmallPtrSet<BasicBlock *, 8> SuccessorBlocks;
+  SuccessorBlocks.insert(SI.getDefaultDest());
+  for (auto I = SI.case_begin(), E = SI.case_end(); I != E; ++I)
+    SuccessorBlocks.insert(I.getCaseSuccessor());
+  // Add cost corresponding to the number of distinct destinations. The first
+  // we model as free because of fallthrough.
+  Cost += (SuccessorBlocks.size() - 1) * InlineConstants::InstrCost;
+  return false;
 }
 
 bool CallAnalyzer::visitIndirectBrInst(IndirectBrInst &IBI) {
@@ -934,7 +946,7 @@ bool CallAnalyzer::analyzeBlock(BasicBlock *BB) {
 /// no constant offsets applied.
 ConstantInt *CallAnalyzer::stripAndComputeInBoundsConstantOffsets(Value *&V) {
   if (!DL || !V->getType()->isPointerTy())
-    return 0;
+    return nullptr;
 
   unsigned IntPtrWidth = DL->getPointerSizeInBits();
   APInt Offset = APInt::getNullValue(IntPtrWidth);
@@ -946,7 +958,7 @@ ConstantInt *CallAnalyzer::stripAndComputeInBoundsConstantOffsets(Value *&V) {
   do {
     if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) {
       if (!GEP->isInBounds() || !accumulateGEPOffset(*GEP, Offset))
-        return 0;
+        return nullptr;
       V = GEP->getPointerOperand();
     } else if (Operator::getOpcode(V) == Instruction::BitCast) {
       V = cast<Operator>(V)->getOperand(0);
@@ -1247,7 +1259,7 @@ InlineCost InlineCostAnalysis::getInlineCost(CallSite CS, Function *Callee,
 
   // Calls to functions with always-inline attributes should be inlined
   // whenever possible.
-  if (Callee->hasFnAttribute(Attribute::AlwaysInline)) {
+  if (CS.hasFnAttr(Attribute::AlwaysInline)) {
     if (isInlineViable(*Callee))
       return llvm::InlineCost::getAlways();
     return llvm::InlineCost::getNever();