Revert "ValueMapper: Eliminate cross-file co-recursion, NFC"

This reverts commit r266503, in case it's the root cause of this bot
failure:

  http://lab.llvm.org:8011/builders/lld-x86_64-freebsd/builds/16810

I'm also reverting r266505 -- "ValueMapper: Use API from r266503 in unit
tests, NFC" -- since it's in the way.

llvm-svn: 266507

1 files changed, 61 insertions, 303 deletions

diff --git a/llvm/lib/Transforms/Utils/ValueMapper.cpp b/llvm/lib/Transforms/Utils/ValueMapper.cpp
index db984eef59c..102f641ebfc 100644
--- a/llvm/lib/Transforms/Utils/ValueMapper.cpp
+++ b/llvm/lib/Transforms/Utils/ValueMapper.cpp
@@ -16,8 +16,6 @@
 #include "llvm/IR/CallSite.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/Function.h"
-#include "llvm/IR/GlobalAlias.h"
-#include "llvm/IR/GlobalVariable.h"
 #include "llvm/IR/InlineAsm.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/Metadata.h"
@@ -32,6 +30,14 @@ void ValueMaterializer::materializeInitFor(GlobalValue *New, GlobalValue *Old) {
 
 namespace {
 
+/// A GlobalValue whose initializer needs to be materialized.
+struct DelayedGlobalValueInit {
+  GlobalValue *Old;
+  GlobalValue *New;
+  DelayedGlobalValueInit(const GlobalValue *Old, GlobalValue *New)
+      : Old(const_cast<GlobalValue *>(Old)), New(New) {}
+};
+
 /// A basic block used in a BlockAddress whose function body is not yet
 /// materialized.
 struct DelayedBasicBlock {
@@ -52,88 +58,30 @@ struct DelayedBasicBlock {
         TempBB(BasicBlock::Create(Old.getContext())) {}
 };
 
-struct WorklistEntry {
-  enum EntryKind {
-    MapGlobalInit,
-    MapAppendingVar,
-    MapGlobalAliasee,
-    RemapFunction
-  };
-  struct GVInitTy {
-    GlobalVariable *GV;
-    Constant *Init;
-  };
-  struct AppendingGVTy {
-    GlobalVariable *GV;
-    Constant *InitPrefix;
-  };
-  struct GlobalAliaseeTy {
-    GlobalAlias *GA;
-    Constant *Aliasee;
-  };
-
-  unsigned Kind : 2;
-  unsigned MCID : 29;
-  unsigned AppendingGVIsOldCtorDtor : 1;
-  unsigned AppendingGVNumNewMembers;
-  union {
-    GVInitTy GVInit;
-    AppendingGVTy AppendingGV;
-    GlobalAliaseeTy GlobalAliasee;
-    Function *RemapF;
-  } Data;
-};
-
-struct MappingContext {
-  ValueToValueMapTy *VM;
-  ValueMaterializer *Materializer = nullptr;
-
-  /// Construct a MappingContext with a value map and materializer.
-  explicit MappingContext(ValueToValueMapTy &VM,
-                          ValueMaterializer *Materializer = nullptr)
-      : VM(&VM), Materializer(Materializer) {}
-};
-
 class MDNodeMapper;
 class Mapper {
   friend class MDNodeMapper;
 
+  ValueToValueMapTy *VM;
   RemapFlags Flags;
   ValueMapTypeRemapper *TypeMapper;
-  unsigned CurrentMCID = 0;
-  SmallVector<MappingContext, 2> MCs;
-  SmallVector<WorklistEntry, 4> Worklist;
+  ValueMaterializer *Materializer;
+
+  SmallVector<DelayedGlobalValueInit, 8> DelayedInits;
   SmallVector<DelayedBasicBlock, 1> DelayedBBs;
-  SmallVector<Constant *, 16> AppendingInits;
 
 public:
   Mapper(ValueToValueMapTy &VM, RemapFlags Flags,
          ValueMapTypeRemapper *TypeMapper, ValueMaterializer *Materializer)
-      : Flags(Flags), TypeMapper(TypeMapper),
-        MCs(1, MappingContext(VM, Materializer)) {}
+      : VM(&VM), Flags(Flags), TypeMapper(TypeMapper),
+        Materializer(Materializer) {}
 
-  /// ValueMapper should explicitly call \a flush() before destruction.
-  ~Mapper() { assert(!hasWorkToDo() && "Expected to be flushed"); }
-
-  bool hasWorkToDo() const { return !Worklist.empty(); }
-
-  unsigned
-  registerAlternateMappingContext(ValueToValueMapTy &VM,
-                                  ValueMaterializer *Materializer = nullptr) {
-    MCs.push_back(MappingContext(VM, Materializer));
-    return MCs.size() - 1;
-  }
-
-  void addFlags(RemapFlags Flags);
+  ~Mapper();
 
   Value *mapValue(const Value *V);
   void remapInstruction(Instruction *I);
   void remapFunction(Function &F);
 
-  Constant *mapConstant(const Constant *C) {
-    return cast_or_null<Constant>(mapValue(C));
-  }
-
   /// Map metadata.
   ///
   /// Find the mapping for MD.  Guarantees that the return will be resolved
@@ -154,28 +102,8 @@ public:
   // through metadata operands, always return nullptr on unmapped locals.
   Metadata *mapLocalAsMetadata(const LocalAsMetadata &LAM);
 
-  void scheduleMapGlobalInitializer(GlobalVariable &GV, Constant &Init,
-                                    unsigned MCID);
-  void scheduleMapAppendingVariable(GlobalVariable &GV, Constant *InitPrefix,
-                                    bool IsOldCtorDtor,
-                                    ArrayRef<Constant *> NewMembers,
-                                    unsigned MCID);
-  void scheduleMapGlobalAliasee(GlobalAlias &GA, Constant &Aliasee,
-                                unsigned MCID);
-  void scheduleRemapFunction(Function &F, unsigned MCID);
-
-  void flush();
-
 private:
-  void mapGlobalInitializer(GlobalVariable &GV, Constant &Init);
-  void mapAppendingVariable(GlobalVariable &GV, Constant *InitPrefix,
-                            bool IsOldCtorDtor,
-                            ArrayRef<Constant *> NewMembers);
-  void mapGlobalAliasee(GlobalAlias &GA, Constant &Aliasee);
-  void remapFunction(Function &F, ValueToValueMapTy &VM);
-
-  ValueToValueMapTy &getVM() { return *MCs[CurrentMCID].VM; }
-  ValueMaterializer *getMaterializer() { return MCs[CurrentMCID].Materializer; }
+  ValueToValueMapTy &getVM() { return *VM; }
 
   Value *mapBlockAddress(const BlockAddress &BA);
 
@@ -336,6 +264,12 @@ private:
 
 } // end namespace
 
+Value *llvm::MapValue(const Value *V, ValueToValueMapTy &VM, RemapFlags Flags,
+                      ValueMapTypeRemapper *TypeMapper,
+                      ValueMaterializer *Materializer) {
+  return Mapper(VM, Flags, TypeMapper, Materializer).mapValue(V);
+}
+
 Value *Mapper::mapValue(const Value *V) {
   ValueToValueMapTy::iterator I = getVM().find(V);
 
@@ -344,13 +278,13 @@ Value *Mapper::mapValue(const Value *V) {
     return I->second;
 
   // If we have a materializer and it can materialize a value, use that.
-  if (auto *Materializer = getMaterializer()) {
+  if (Materializer) {
     if (Value *NewV =
             Materializer->materializeDeclFor(const_cast<Value *>(V))) {
       getVM()[V] = NewV;
       if (auto *NewGV = dyn_cast<GlobalValue>(NewV))
-        Materializer->materializeInitFor(
-            NewGV, cast<GlobalValue>(const_cast<Value *>(V)));
+        DelayedInits.push_back(
+            DelayedGlobalValueInit(cast<GlobalValue>(V), NewGV));
       return NewV;
     }
   }
@@ -750,6 +684,12 @@ Optional<Metadata *> Mapper::mapSimpleMetadata(const Metadata *MD) {
   return None;
 }
 
+Metadata *llvm::MapMetadata(const Metadata *MD, ValueToValueMapTy &VM,
+                            RemapFlags Flags, ValueMapTypeRemapper *TypeMapper,
+                            ValueMaterializer *Materializer) {
+  return Mapper(VM, Flags, TypeMapper, Materializer).mapMetadata(MD);
+}
+
 Metadata *Mapper::mapLocalAsMetadata(const LocalAsMetadata &LAM) {
   // Lookup the mapping for the value itself, and return the appropriate
   // metadata.
@@ -776,42 +716,36 @@ Metadata *Mapper::mapMetadata(const Metadata *MD) {
   return MDNodeMapper(*this).map(*cast<MDNode>(MD));
 }
 
-void Mapper::flush() {
-  // Flush out the worklist of global values.
-  while (!Worklist.empty()) {
-    WorklistEntry E = Worklist.pop_back_val();
-    CurrentMCID = E.MCID;
-    switch (E.Kind) {
-    case WorklistEntry::MapGlobalInit:
-      E.Data.GVInit.GV->setInitializer(mapConstant(E.Data.GVInit.Init));
-      break;
-    case WorklistEntry::MapAppendingVar: {
-      unsigned PrefixSize = AppendingInits.size() - E.AppendingGVNumNewMembers;
-      mapAppendingVariable(*E.Data.AppendingGV.GV,
-                           E.Data.AppendingGV.InitPrefix,
-                           E.AppendingGVIsOldCtorDtor,
-                           makeArrayRef(AppendingInits).slice(PrefixSize));
-      AppendingInits.resize(PrefixSize);
-      break;
-    }
-    case WorklistEntry::MapGlobalAliasee:
-      E.Data.GlobalAliasee.GA->setAliasee(
-          mapConstant(E.Data.GlobalAliasee.Aliasee));
-      break;
-    case WorklistEntry::RemapFunction:
-      remapFunction(*E.Data.RemapF);
-      break;
-    }
+Mapper::~Mapper() {
+  // Materialize global initializers.
+  while (!DelayedInits.empty()) {
+    auto Init = DelayedInits.pop_back_val();
+    Materializer->materializeInitFor(Init.New, Init.Old);
   }
-  CurrentMCID = 0;
 
-  // Finish logic for block addresses now that all global values have been
-  // handled.
+  // Process block addresses delayed until global inits.
   while (!DelayedBBs.empty()) {
     DelayedBasicBlock DBB = DelayedBBs.pop_back_val();
     BasicBlock *BB = cast_or_null<BasicBlock>(mapValue(DBB.OldBB));
     DBB.TempBB->replaceAllUsesWith(BB ? BB : DBB.OldBB);
   }
+
+  // We don't expect these to grow after clearing.
+  assert(DelayedInits.empty());
+  assert(DelayedBBs.empty());
+}
+
+MDNode *llvm::MapMetadata(const MDNode *MD, ValueToValueMapTy &VM,
+                          RemapFlags Flags, ValueMapTypeRemapper *TypeMapper,
+                          ValueMaterializer *Materializer) {
+  return cast_or_null<MDNode>(MapMetadata(static_cast<const Metadata *>(MD), VM,
+                                          Flags, TypeMapper, Materializer));
+}
+
+void llvm::RemapInstruction(Instruction *I, ValueToValueMapTy &VM,
+                            RemapFlags Flags, ValueMapTypeRemapper *TypeMapper,
+                            ValueMaterializer *Materializer) {
+  Mapper(VM, Flags, TypeMapper, Materializer).remapInstruction(I);
 }
 
 void Mapper::remapInstruction(Instruction *I) {
@@ -848,7 +782,7 @@ void Mapper::remapInstruction(Instruction *I) {
     if (New != Old)
       I->setMetadata(MI.first, New);
   }
-
+  
   if (!TypeMapper)
     return;
 
@@ -874,6 +808,12 @@ void Mapper::remapInstruction(Instruction *I) {
   I->mutateType(TypeMapper->remapType(I->getType()));
 }
 
+void llvm::RemapFunction(Function &F, ValueToValueMapTy &VM, RemapFlags Flags,
+                         ValueMapTypeRemapper *TypeMapper,
+                         ValueMaterializer *Materializer) {
+  Mapper(VM, Flags, TypeMapper, Materializer).remapFunction(F);
+}
+
 void Mapper::remapFunction(Function &F) {
   // Remap the operands.
   for (Use &Op : F.operands())
@@ -896,185 +836,3 @@ void Mapper::remapFunction(Function &F) {
     for (Instruction &I : BB)
       remapInstruction(&I);
 }
-
-void Mapper::mapAppendingVariable(GlobalVariable &GV, Constant *InitPrefix,
-                                  bool IsOldCtorDtor,
-                                  ArrayRef<Constant *> NewMembers) {
-  SmallVector<Constant *, 16> Elements;
-  if (InitPrefix) {
-    unsigned NumElements =
-        cast<ArrayType>(InitPrefix->getType())->getNumElements();
-    for (unsigned I = 0; I != NumElements; ++I)
-      Elements.push_back(InitPrefix->getAggregateElement(I));
-  }
-
-  PointerType *VoidPtrTy;
-  Type *EltTy;
-  if (IsOldCtorDtor) {
-    // FIXME: This upgrade is done during linking to support the C API.  See
-    // also IRLinker::linkAppendingVarProto() in IRMover.cpp.
-    VoidPtrTy = Type::getInt8Ty(GV.getContext())->getPointerTo();
-    auto &ST = *cast<StructType>(NewMembers.front()->getType());
-    Type *Tys[3] = {ST.getElementType(0), ST.getElementType(1), VoidPtrTy};
-    EltTy = StructType::get(GV.getContext(), Tys, false);
-  }
-
-  for (auto *V : NewMembers) {
-    Constant *NewV;
-    if (IsOldCtorDtor) {
-      auto *S = cast<ConstantStruct>(V);
-      auto *E1 = mapValue(S->getOperand(0));
-      auto *E2 = mapValue(S->getOperand(1));
-      Value *Null = Constant::getNullValue(VoidPtrTy);
-      NewV =
-          ConstantStruct::get(cast<StructType>(EltTy), E1, E2, Null, nullptr);
-    } else {
-      NewV = cast_or_null<Constant>(mapValue(V));
-    }
-    Elements.push_back(NewV);
-  }
-
-  GV.setInitializer(ConstantArray::get(
-      cast<ArrayType>(GV.getType()->getElementType()), Elements));
-}
-
-void Mapper::scheduleMapGlobalInitializer(GlobalVariable &GV, Constant &Init,
-                                          unsigned MCID) {
-  assert(MCID < MCs.size() && "Invalid mapping context");
-
-  WorklistEntry WE;
-  WE.Kind = WorklistEntry::MapGlobalInit;
-  WE.MCID = MCID;
-  WE.Data.GVInit.GV = &GV;
-  WE.Data.GVInit.Init = &Init;
-  Worklist.push_back(WE);
-}
-
-void Mapper::scheduleMapAppendingVariable(GlobalVariable &GV,
-                                          Constant *InitPrefix,
-                                          bool IsOldCtorDtor,
-                                          ArrayRef<Constant *> NewMembers,
-                                          unsigned MCID) {
-  assert(MCID < MCs.size() && "Invalid mapping context");
-
-  WorklistEntry WE;
-  WE.Kind = WorklistEntry::MapAppendingVar;
-  WE.MCID = MCID;
-  WE.Data.AppendingGV.GV = &GV;
-  WE.Data.AppendingGV.InitPrefix = InitPrefix;
-  WE.AppendingGVIsOldCtorDtor = IsOldCtorDtor;
-  WE.AppendingGVNumNewMembers = NewMembers.size();
-  Worklist.push_back(WE);
-  AppendingInits.append(NewMembers.begin(), NewMembers.end());
-}
-
-void Mapper::scheduleMapGlobalAliasee(GlobalAlias &GA, Constant &Aliasee,
-                                      unsigned MCID) {
-  assert(MCID < MCs.size() && "Invalid mapping context");
-
-  WorklistEntry WE;
-  WE.Kind = WorklistEntry::MapGlobalAliasee;
-  WE.MCID = MCID;
-  WE.Data.GlobalAliasee.GA = &GA;
-  WE.Data.GlobalAliasee.Aliasee = &Aliasee;
-  Worklist.push_back(WE);
-}
-
-void Mapper::scheduleRemapFunction(Function &F, unsigned MCID) {
-  assert(MCID < MCs.size() && "Invalid mapping context");
-
-  WorklistEntry WE;
-  WE.Kind = WorklistEntry::RemapFunction;
-  WE.MCID = MCID;
-  WE.Data.RemapF = &F;
-  Worklist.push_back(WE);
-}
-
-void Mapper::addFlags(RemapFlags Flags) {
-  assert(!hasWorkToDo() && "Expected to have flushed the worklist");
-  this->Flags = this->Flags | Flags;
-}
-
-static Mapper *getAsMapper(void *pImpl) {
-  return reinterpret_cast<Mapper *>(pImpl);
-}
-
-namespace {
-
-class FlushingMapper {
-  Mapper &M;
-
-public:
-  explicit FlushingMapper(void *pImpl) : M(*getAsMapper(pImpl)) {
-    assert(!M.hasWorkToDo() && "Expected to be flushed");
-  }
-  ~FlushingMapper() { M.flush(); }
-  Mapper *operator->() const { return &M; }
-};
-
-} // end namespace
-
-ValueMapper::ValueMapper(ValueToValueMapTy &VM, RemapFlags Flags,
-                         ValueMapTypeRemapper *TypeMapper,
-                         ValueMaterializer *Materializer)
-    : pImpl(new Mapper(VM, Flags, TypeMapper, Materializer)) {}
-
-ValueMapper::~ValueMapper() { delete getAsMapper(pImpl); }
-
-unsigned
-ValueMapper::registerAlternateMappingContext(ValueToValueMapTy &VM,
-                                             ValueMaterializer *Materializer) {
-  return getAsMapper(pImpl)->registerAlternateMappingContext(VM, Materializer);
-}
-
-void ValueMapper::addFlags(RemapFlags Flags) {
-  FlushingMapper(pImpl)->addFlags(Flags);
-}
-
-Value *ValueMapper::mapValue(const Value &V) {
-  return FlushingMapper(pImpl)->mapValue(&V);
-}
-
-Constant *ValueMapper::mapConstant(const Constant &C) {
-  return cast_or_null<Constant>(mapValue(C));
-}
-
-Metadata *ValueMapper::mapMetadata(const Metadata &MD) {
-  return FlushingMapper(pImpl)->mapMetadata(&MD);
-}
-
-MDNode *ValueMapper::mapMDNode(const MDNode &N) {
-  return cast_or_null<MDNode>(mapMetadata(N));
-}
-
-void ValueMapper::remapInstruction(Instruction &I) {
-  FlushingMapper(pImpl)->remapInstruction(&I);
-}
-
-void ValueMapper::remapFunction(Function &F) {
-  FlushingMapper(pImpl)->remapFunction(F);
-}
-
-void ValueMapper::scheduleMapGlobalInitializer(GlobalVariable &GV,
-                                               Constant &Init,
-                                               unsigned MCID) {
-  getAsMapper(pImpl)->scheduleMapGlobalInitializer(GV, Init, MCID);
-}
-
-void ValueMapper::scheduleMapAppendingVariable(GlobalVariable &GV,
-                                               Constant *InitPrefix,
-                                               bool IsOldCtorDtor,
-                                               ArrayRef<Constant *> NewMembers,
-                                               unsigned MCID) {
-  getAsMapper(pImpl)->scheduleMapAppendingVariable(
-      GV, InitPrefix, IsOldCtorDtor, NewMembers, MCID);
-}
-
-void ValueMapper::scheduleMapGlobalAliasee(GlobalAlias &GA, Constant &Aliasee,
-                                           unsigned MCID) {
-  getAsMapper(pImpl)->scheduleMapGlobalAliasee(GA, Aliasee, MCID);
-}
-
-void ValueMapper::scheduleRemapFunction(Function &F, unsigned MCID) {
-  getAsMapper(pImpl)->scheduleRemapFunction(F, MCID);
-}