Imported Upstream version 6.4.0.137

Former-commit-id: 943baa9f16a098c33e129777827f3a9d20da00d6

external/llvm/lib/Transforms/IPO/DeadArgumentElimination.cpp

@@ -507,14 +507,28 @@ void DeadArgumentEliminationPass::SurveyFunction(const Function &F) {
   // MaybeLive. Initialized to a list of RetCount empty lists.
   RetUses MaybeLiveRetUses(RetCount);
 
-  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
-    if (const ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator()))
+  bool HasMustTailCalls = false;
+
+  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
+    if (const ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator())) {
       if (RI->getNumOperands() != 0 && RI->getOperand(0)->getType()
           != F.getFunctionType()->getReturnType()) {
         // We don't support old style multiple return values.
         MarkLive(F);
         return;
       }
+    }
+
+    // If we have any returns of `musttail` results - the signature can't
+    // change
+    if (BB->getTerminatingMustTailCall() != nullptr)
+      HasMustTailCalls = true;
+  }
+
+  if (HasMustTailCalls) {
+    DEBUG(dbgs() << "DeadArgumentEliminationPass - " << F.getName()
+                 << " has musttail calls\n");
+  }
 
   if (!F.hasLocalLinkage() && (!ShouldHackArguments || F.isIntrinsic())) {
     MarkLive(F);
@@ -526,6 +540,9 @@ void DeadArgumentEliminationPass::SurveyFunction(const Function &F) {
   // Keep track of the number of live retvals, so we can skip checks once all
   // of them turn out to be live.
   unsigned NumLiveRetVals = 0;
+
+  bool HasMustTailCallers = false;
+
   // Loop all uses of the function.
   for (const Use &U : F.uses()) {
     // If the function is PASSED IN as an argument, its address has been
@@ -536,6 +553,11 @@ void DeadArgumentEliminationPass::SurveyFunction(const Function &F) {
       return;
     }
 
+    // The number of arguments for `musttail` call must match the number of
+    // arguments of the caller
+    if (CS.isMustTailCall())
+      HasMustTailCallers = true;
+
     // If this use is anything other than a call site, the function is alive.
     const Instruction *TheCall = CS.getInstruction();
     if (!TheCall) {   // Not a direct call site?
@@ -580,6 +602,11 @@ void DeadArgumentEliminationPass::SurveyFunction(const Function &F) {
     }
   }
 
+  if (HasMustTailCallers) {
+    DEBUG(dbgs() << "DeadArgumentEliminationPass - " << F.getName()
+                 << " has musttail callers\n");
+  }
+
   // Now we've inspected all callers, record the liveness of our return values.
   for (unsigned i = 0; i != RetCount; ++i)
     MarkValue(CreateRet(&F, i), RetValLiveness[i], MaybeLiveRetUses[i]);
@@ -593,12 +620,19 @@ void DeadArgumentEliminationPass::SurveyFunction(const Function &F) {
   for (Function::const_arg_iterator AI = F.arg_begin(),
        E = F.arg_end(); AI != E; ++AI, ++i) {
     Liveness Result;
-    if (F.getFunctionType()->isVarArg()) {
+    if (F.getFunctionType()->isVarArg() || HasMustTailCallers ||
+        HasMustTailCalls) {
       // Variadic functions will already have a va_arg function expanded inside
       // them, making them potentially very sensitive to ABI changes resulting
       // from removing arguments entirely, so don't. For example AArch64 handles
       // register and stack HFAs very differently, and this is reflected in the
       // IR which has already been generated.
+      //
+      // `musttail` calls to this function restrict argument removal attempts.
+      // The signature of the caller must match the signature of the function.
+      //
+      // `musttail` calls in this function prevents us from changing its
+      // signature
       Result = Live;
     } else {
       // See what the effect of this use is (recording any uses that cause

external/llvm/lib/Transforms/IPO/MergeFunctions.cpp

@@ -638,6 +638,19 @@ void MergeFunctions::filterInstsUnrelatedToPDI(
   DEBUG(dbgs() << " }\n");
 }
 
+// Don't merge tiny functions using a thunk, since it can just end up
+// making the function larger.
+static bool isThunkProfitable(Function * F) {
+  if (F->size() == 1) {
+    if (F->front().size() <= 2) {
+      DEBUG(dbgs() << "isThunkProfitable: " << F->getName()
+                    << " is too small to bother creating a thunk for\n");
+      return false;
+    }
+  }
+  return true;
+}
+
 // Replace G with a simple tail call to bitcast(F). Also (unless
 // MergeFunctionsPDI holds) replace direct uses of G with bitcast(F),
 // delete G. Under MergeFunctionsPDI, we use G itself for creating
@@ -647,39 +660,6 @@ void MergeFunctions::filterInstsUnrelatedToPDI(
 // For better debugability, under MergeFunctionsPDI, we do not modify G's
 // call sites to point to F even when within the same translation unit.
 void MergeFunctions::writeThunk(Function *F, Function *G) {
-  if (!G->isInterposable() && !MergeFunctionsPDI) {
-    if (G->hasGlobalUnnamedAddr()) {
-      // G might have been a key in our GlobalNumberState, and it's illegal
-      // to replace a key in ValueMap<GlobalValue *> with a non-global.
-      GlobalNumbers.erase(G);
-      // If G's address is not significant, replace it entirely.
-      Constant *BitcastF = ConstantExpr::getBitCast(F, G->getType());
-      G->replaceAllUsesWith(BitcastF);
-    } else {
-      // Redirect direct callers of G to F. (See note on MergeFunctionsPDI
-      // above).
-      replaceDirectCallers(G, F);
-    }
-  }
-
-  // If G was internal then we may have replaced all uses of G with F. If so,
-  // stop here and delete G. There's no need for a thunk. (See note on
-  // MergeFunctionsPDI above).
-  if (G->hasLocalLinkage() && G->use_empty() && !MergeFunctionsPDI) {
-    G->eraseFromParent();
-    return;
-  }
-
-  // Don't merge tiny functions using a thunk, since it can just end up
-  // making the function larger.
-  if (F->size() == 1) {
-    if (F->front().size() <= 2) {
-      DEBUG(dbgs() << "writeThunk: " << F->getName()
-                   << " is too small to bother creating a thunk for\n");
-      return;
-    }
-  }
-
   BasicBlock *GEntryBlock = nullptr;
   std::vector<Instruction *> PDIUnrelatedWL;
   BasicBlock *BB = nullptr;
@@ -754,6 +734,10 @@ void MergeFunctions::mergeTwoFunctions(Function *F, Function *G) {
   if (F->isInterposable()) {
     assert(G->isInterposable());
 
+    if (!isThunkProfitable(F)) {
+      return;
+    }
+
     // Make them both thunks to the same internal function.
     Function *H = Function::Create(F->getFunctionType(), F->getLinkage(), "",
                                    F->getParent());
@@ -770,11 +754,41 @@ void MergeFunctions::mergeTwoFunctions(Function *F, Function *G) {
     F->setAlignment(MaxAlignment);
     F->setLinkage(GlobalValue::PrivateLinkage);
     ++NumDoubleWeak;
+    ++NumFunctionsMerged;
   } else {
-    writeThunk(F, G);
-  }
+    // For better debugability, under MergeFunctionsPDI, we do not modify G's
+    // call sites to point to F even when within the same translation unit.
+    if (!G->isInterposable() && !MergeFunctionsPDI) {
+      if (G->hasGlobalUnnamedAddr()) {
+        // G might have been a key in our GlobalNumberState, and it's illegal
+        // to replace a key in ValueMap<GlobalValue *> with a non-global.
+        GlobalNumbers.erase(G);
+        // If G's address is not significant, replace it entirely.
+        Constant *BitcastF = ConstantExpr::getBitCast(F, G->getType());
+        G->replaceAllUsesWith(BitcastF);
+      } else {
+        // Redirect direct callers of G to F. (See note on MergeFunctionsPDI
+        // above).
+        replaceDirectCallers(G, F);
+      }
+    }
 
-  ++NumFunctionsMerged;
+    // If G was internal then we may have replaced all uses of G with F. If so,
+    // stop here and delete G. There's no need for a thunk. (See note on
+    // MergeFunctionsPDI above).
+    if (G->hasLocalLinkage() && G->use_empty() && !MergeFunctionsPDI) {
+      G->eraseFromParent();
+      ++NumFunctionsMerged;
+      return;
+    }
+
+    if (!isThunkProfitable(F)) {
+      return;
+    }
+
+    writeThunk(F, G);
+    ++NumFunctionsMerged;
+  }
 }
 
 /// Replace function F by function G.

external/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp.REMOVED.git-id

@@ -1 +1 @@
-35ed592ac07d8e8a22a6b66073705c0d84ce501e
+8fa7d0684b94d2ad273f4204ed8a51d41f668b20

external/llvm/lib/Transforms/Scalar/DivRemPairs.cpp

@@ -13,6 +13,8 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/Scalar/DivRemPairs.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/MapVector.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/GlobalsModRef.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
@@ -48,7 +50,10 @@ static bool optimizeDivRem(Function &F, const TargetTransformInfo &TTI,
 
   // Insert all divide and remainder instructions into maps keyed by their
   // operands and opcode (signed or unsigned).
-  DenseMap<DivRemMapKey, Instruction *> DivMap, RemMap;
+  DenseMap<DivRemMapKey, Instruction *> DivMap;
+  // Use a MapVector for RemMap so that instructions are moved/inserted in a
+  // deterministic order.
+  MapVector<DivRemMapKey, Instruction *> RemMap;
   for (auto &BB : F) {
     for (auto &I : BB) {
       if (I.getOpcode() == Instruction::SDiv)
@@ -67,14 +72,14 @@ static bool optimizeDivRem(Function &F, const TargetTransformInfo &TTI,
   // rare than division.
   for (auto &RemPair : RemMap) {
     // Find the matching division instruction from the division map.
-    Instruction *DivInst = DivMap[RemPair.getFirst()];
+    Instruction *DivInst = DivMap[RemPair.first];
     if (!DivInst)
       continue;
 
     // We have a matching pair of div/rem instructions. If one dominates the
     // other, hoist and/or replace one.
     NumPairs++;
-    Instruction *RemInst = RemPair.getSecond();
+    Instruction *RemInst = RemPair.second;
     bool IsSigned = DivInst->getOpcode() == Instruction::SDiv;
     bool HasDivRemOp = TTI.hasDivRemOp(DivInst->getType(), IsSigned);
 

external/llvm/lib/Transforms/Scalar/JumpThreading.cpp

@@ -1454,6 +1454,9 @@ FindMostPopularDest(BasicBlock *BB,
     if (PredToDest.second)
       DestPopularity[PredToDest.second]++;
 
+  if (DestPopularity.empty())
+    return nullptr;
+
   // Find the most popular dest.
   DenseMap<BasicBlock*, unsigned>::iterator DPI = DestPopularity.begin();
   BasicBlock *MostPopularDest = DPI->first;
@@ -1629,8 +1632,20 @@ bool JumpThreadingPass::ProcessThreadableEdges(Value *Cond, BasicBlock *BB,
   // threadable destination (the common case) we can avoid this.
   BasicBlock *MostPopularDest = OnlyDest;
 
-  if (MostPopularDest == MultipleDestSentinel)
+  if (MostPopularDest == MultipleDestSentinel) {
+    // Remove any loop headers from the Dest list, ThreadEdge conservatively
+    // won't process them, but we might have other destination that are eligible
+    // and we still want to process.
+    erase_if(PredToDestList,
+             [&](const std::pair<BasicBlock *, BasicBlock *> &PredToDest) {
+               return LoopHeaders.count(PredToDest.second) != 0;
+             });
+
+    if (PredToDestList.empty())
+      return false;
+
     MostPopularDest = FindMostPopularDest(BB, PredToDestList);
+  }
 
   // Now that we know what the most popular destination is, factor all
   // predecessors that will jump to it into a single predecessor.

external/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp

@@ -450,8 +450,10 @@ static bool shouldRewriteFunction(Function &F) {
     const auto &FunctionGCName = F.getGC();
     const StringRef StatepointExampleName("statepoint-example");
     const StringRef CoreCLRName("coreclr");
+    const StringRef MonoName("mono");
     return (StatepointExampleName == FunctionGCName) ||
-           (CoreCLRName == FunctionGCName);
+           (CoreCLRName == FunctionGCName) ||
+           (MonoName == FunctionGCName);
   } else
     return false;
 }

external/llvm/lib/Transforms/Scalar/SCCP.cpp

@@ -1853,6 +1853,7 @@ static void findReturnsToZap(Function &F,
     if (CallInst *CI = BB.getTerminatingMustTailCall()) {
       DEBUG(dbgs() << "Can't zap return of the block due to present "
                    << "musttail call : " << *CI << "\n");
+      (void)CI;
       return;
     }
 

external/llvm/lib/Transforms/Utils/FunctionComparator.cpp

@@ -710,7 +710,7 @@ int FunctionComparator::cmpInlineAsm(const InlineAsm *L,
     return Res;
   if (int Res = cmpNumbers(L->getDialect(), R->getDialect()))
     return Res;
-  llvm_unreachable("InlineAsm blocks were not uniqued.");
+  assert(L->getFunctionType() != R->getFunctionType());
   return 0;
 }