--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/Bitcode/Writer/ValueEnumerator.cpp	Thu Dec 12 13:56:28 2013 +0900
@@ -0,0 +1,545 @@
+//===-- ValueEnumerator.cpp - Number values and types for bitcode writer --===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the ValueEnumerator class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ValueEnumerator.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/ValueSymbolTable.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+using namespace llvm;
+
+static bool isIntOrIntVectorValue(const std::pair<const Value*, unsigned> &V) {
+  return V.first->getType()->isIntOrIntVectorTy();
+}
+
+/// ValueEnumerator - Enumerate module-level information.
+ValueEnumerator::ValueEnumerator(const Module *M) {
+  // Enumerate the global variables.
+  for (Module::const_global_iterator I = M->global_begin(),
+         E = M->global_end(); I != E; ++I)
+    EnumerateValue(I);
+
+  // Enumerate the functions.
+  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I) {
+    EnumerateValue(I);
+    EnumerateAttributes(cast<Function>(I)->getAttributes());
+  }
+
+  // Enumerate the aliases.
+  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
+       I != E; ++I)
+    EnumerateValue(I);
+
+  // Remember what is the cutoff between globalvalue's and other constants.
+  unsigned FirstConstant = Values.size();
+
+  // Enumerate the global variable initializers.
+  for (Module::const_global_iterator I = M->global_begin(),
+         E = M->global_end(); I != E; ++I)
+    if (I->hasInitializer())
+      EnumerateValue(I->getInitializer());
+
+  // Enumerate the aliasees.
+  for (Module::const_alias_iterator I = M->alias_begin(), E = M->alias_end();
+       I != E; ++I)
+    EnumerateValue(I->getAliasee());
+
+  // Enumerate the prefix data constants.
+  for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I)
+    if (I->hasPrefixData())
+      EnumerateValue(I->getPrefixData());
+
+  // Insert constants and metadata that are named at module level into the slot
+  // pool so that the module symbol table can refer to them...
+  EnumerateValueSymbolTable(M->getValueSymbolTable());
+  EnumerateNamedMetadata(M);
+
+  SmallVector<std::pair<unsigned, MDNode*>, 8> MDs;
+
+  // Enumerate types used by function bodies and argument lists.
+  for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
+
+    for (Function::const_arg_iterator I = F->arg_begin(), E = F->arg_end();
+         I != E; ++I)
+      EnumerateType(I->getType());
+
+    for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
+      for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E;++I){
+        for (User::const_op_iterator OI = I->op_begin(), E = I->op_end();
+             OI != E; ++OI) {
+          if (MDNode *MD = dyn_cast<MDNode>(*OI))
+            if (MD->isFunctionLocal() && MD->getFunction())
+              // These will get enumerated during function-incorporation.
+              continue;
+          EnumerateOperandType(*OI);
+        }
+        EnumerateType(I->getType());
+        if (const CallInst *CI = dyn_cast<CallInst>(I))
+          EnumerateAttributes(CI->getAttributes());
+        else if (const InvokeInst *II = dyn_cast<InvokeInst>(I))
+          EnumerateAttributes(II->getAttributes());
+
+        // Enumerate metadata attached with this instruction.
+        MDs.clear();
+        I->getAllMetadataOtherThanDebugLoc(MDs);
+        for (unsigned i = 0, e = MDs.size(); i != e; ++i)
+          EnumerateMetadata(MDs[i].second);
+
+        if (!I->getDebugLoc().isUnknown()) {
+          MDNode *Scope, *IA;
+          I->getDebugLoc().getScopeAndInlinedAt(Scope, IA, I->getContext());
+          if (Scope) EnumerateMetadata(Scope);
+          if (IA) EnumerateMetadata(IA);
+        }
+      }
+  }
+
+  // Optimize constant ordering.
+  OptimizeConstants(FirstConstant, Values.size());
+}
+
+unsigned ValueEnumerator::getInstructionID(const Instruction *Inst) const {
+  InstructionMapType::const_iterator I = InstructionMap.find(Inst);
+  assert(I != InstructionMap.end() && "Instruction is not mapped!");
+  return I->second;
+}
+
+void ValueEnumerator::setInstructionID(const Instruction *I) {
+  InstructionMap[I] = InstructionCount++;
+}
+
+unsigned ValueEnumerator::getValueID(const Value *V) const {
+  if (isa<MDNode>(V) || isa<MDString>(V)) {
+    ValueMapType::const_iterator I = MDValueMap.find(V);
+    assert(I != MDValueMap.end() && "Value not in slotcalculator!");
+    return I->second-1;
+  }
+
+  ValueMapType::const_iterator I = ValueMap.find(V);
+  assert(I != ValueMap.end() && "Value not in slotcalculator!");
+  return I->second-1;
+}
+
+void ValueEnumerator::dump() const {
+  print(dbgs(), ValueMap, "Default");
+  dbgs() << '\n';
+  print(dbgs(), MDValueMap, "MetaData");
+  dbgs() << '\n';
+}
+
+void ValueEnumerator::print(raw_ostream &OS, const ValueMapType &Map,
+                            const char *Name) const {
+
+  OS << "Map Name: " << Name << "\n";
+  OS << "Size: " << Map.size() << "\n";
+  for (ValueMapType::const_iterator I = Map.begin(),
+         E = Map.end(); I != E; ++I) {
+
+    const Value *V = I->first;
+    if (V->hasName())
+      OS << "Value: " << V->getName();
+    else
+      OS << "Value: [null]\n";
+    V->dump();
+
+    OS << " Uses(" << std::distance(V->use_begin(),V->use_end()) << "):";
+    for (Value::const_use_iterator UI = V->use_begin(), UE = V->use_end();
+         UI != UE; ++UI) {
+      if (UI != V->use_begin())
+        OS << ",";
+      if((*UI)->hasName())
+        OS << " " << (*UI)->getName();
+      else
+        OS << " [null]";
+
+    }
+    OS <<  "\n\n";
+  }
+}
+
+// Optimize constant ordering.
+namespace {
+  struct CstSortPredicate {
+    ValueEnumerator &VE;
+    explicit CstSortPredicate(ValueEnumerator &ve) : VE(ve) {}
+    bool operator()(const std::pair<const Value*, unsigned> &LHS,
+                    const std::pair<const Value*, unsigned> &RHS) {
+      // Sort by plane.
+      if (LHS.first->getType() != RHS.first->getType())
+        return VE.getTypeID(LHS.first->getType()) <
+               VE.getTypeID(RHS.first->getType());
+      // Then by frequency.
+      return LHS.second > RHS.second;
+    }
+  };
+}
+
+/// OptimizeConstants - Reorder constant pool for denser encoding.
+void ValueEnumerator::OptimizeConstants(unsigned CstStart, unsigned CstEnd) {
+  if (CstStart == CstEnd || CstStart+1 == CstEnd) return;
+
+  CstSortPredicate P(*this);
+  std::stable_sort(Values.begin()+CstStart, Values.begin()+CstEnd, P);
+
+  // Ensure that integer and vector of integer constants are at the start of the
+  // constant pool.  This is important so that GEP structure indices come before
+  // gep constant exprs.
+  std::partition(Values.begin()+CstStart, Values.begin()+CstEnd,
+                 isIntOrIntVectorValue);
+
+  // Rebuild the modified portion of ValueMap.
+  for (; CstStart != CstEnd; ++CstStart)
+    ValueMap[Values[CstStart].first] = CstStart+1;
+}
+
+
+/// EnumerateValueSymbolTable - Insert all of the values in the specified symbol
+/// table into the values table.
+void ValueEnumerator::EnumerateValueSymbolTable(const ValueSymbolTable &VST) {
+  for (ValueSymbolTable::const_iterator VI = VST.begin(), VE = VST.end();
+       VI != VE; ++VI)
+    EnumerateValue(VI->getValue());
+}
+
+/// EnumerateNamedMetadata - Insert all of the values referenced by
+/// named metadata in the specified module.
+void ValueEnumerator::EnumerateNamedMetadata(const Module *M) {
+  for (Module::const_named_metadata_iterator I = M->named_metadata_begin(),
+       E = M->named_metadata_end(); I != E; ++I)
+    EnumerateNamedMDNode(I);
+}
+
+void ValueEnumerator::EnumerateNamedMDNode(const NamedMDNode *MD) {
+  for (unsigned i = 0, e = MD->getNumOperands(); i != e; ++i)
+    EnumerateMetadata(MD->getOperand(i));
+}
+
+/// EnumerateMDNodeOperands - Enumerate all non-function-local values
+/// and types referenced by the given MDNode.
+void ValueEnumerator::EnumerateMDNodeOperands(const MDNode *N) {
+  for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
+    if (Value *V = N->getOperand(i)) {
+      if (isa<MDNode>(V) || isa<MDString>(V))
+        EnumerateMetadata(V);
+      else if (!isa<Instruction>(V) && !isa<Argument>(V))
+        EnumerateValue(V);
+    } else
+      EnumerateType(Type::getVoidTy(N->getContext()));
+  }
+}
+
+void ValueEnumerator::EnumerateMetadata(const Value *MD) {
+  assert((isa<MDNode>(MD) || isa<MDString>(MD)) && "Invalid metadata kind");
+
+  // Enumerate the type of this value.
+  EnumerateType(MD->getType());
+
+  const MDNode *N = dyn_cast<MDNode>(MD);
+
+  // In the module-level pass, skip function-local nodes themselves, but
+  // do walk their operands.
+  if (N && N->isFunctionLocal() && N->getFunction()) {
+    EnumerateMDNodeOperands(N);
+    return;
+  }
+
+  // Check to see if it's already in!
+  unsigned &MDValueID = MDValueMap[MD];
+  if (MDValueID) {
+    // Increment use count.
+    MDValues[MDValueID-1].second++;
+    return;
+  }
+  MDValues.push_back(std::make_pair(MD, 1U));
+  MDValueID = MDValues.size();
+
+  // Enumerate all non-function-local operands.
+  if (N)
+    EnumerateMDNodeOperands(N);
+}
+
+/// EnumerateFunctionLocalMetadataa - Incorporate function-local metadata
+/// information reachable from the given MDNode.
+void ValueEnumerator::EnumerateFunctionLocalMetadata(const MDNode *N) {
+  assert(N->isFunctionLocal() && N->getFunction() &&
+         "EnumerateFunctionLocalMetadata called on non-function-local mdnode!");
+
+  // Enumerate the type of this value.
+  EnumerateType(N->getType());
+
+  // Check to see if it's already in!
+  unsigned &MDValueID = MDValueMap[N];
+  if (MDValueID) {
+    // Increment use count.
+    MDValues[MDValueID-1].second++;
+    return;
+  }
+  MDValues.push_back(std::make_pair(N, 1U));
+  MDValueID = MDValues.size();
+
+  // To incoroporate function-local information visit all function-local
+  // MDNodes and all function-local values they reference.
+  for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
+    if (Value *V = N->getOperand(i)) {
+      if (MDNode *O = dyn_cast<MDNode>(V)) {
+        if (O->isFunctionLocal() && O->getFunction())
+          EnumerateFunctionLocalMetadata(O);
+      } else if (isa<Instruction>(V) || isa<Argument>(V))
+        EnumerateValue(V);
+    }
+
+  // Also, collect all function-local MDNodes for easy access.
+  FunctionLocalMDs.push_back(N);
+}
+
+void ValueEnumerator::EnumerateValue(const Value *V) {
+  assert(!V->getType()->isVoidTy() && "Can't insert void values!");
+  assert(!isa<MDNode>(V) && !isa<MDString>(V) &&
+         "EnumerateValue doesn't handle Metadata!");
+
+  // Check to see if it's already in!
+  unsigned &ValueID = ValueMap[V];
+  if (ValueID) {
+    // Increment use count.
+    Values[ValueID-1].second++;
+    return;
+  }
+
+  // Enumerate the type of this value.
+  EnumerateType(V->getType());
+
+  if (const Constant *C = dyn_cast<Constant>(V)) {
+    if (isa<GlobalValue>(C)) {
+      // Initializers for globals are handled explicitly elsewhere.
+    } else if (C->getNumOperands()) {
+      // If a constant has operands, enumerate them.  This makes sure that if a
+      // constant has uses (for example an array of const ints), that they are
+      // inserted also.
+
+      // We prefer to enumerate them with values before we enumerate the user
+      // itself.  This makes it more likely that we can avoid forward references
+      // in the reader.  We know that there can be no cycles in the constants
+      // graph that don't go through a global variable.
+      for (User::const_op_iterator I = C->op_begin(), E = C->op_end();
+           I != E; ++I)
+        if (!isa<BasicBlock>(*I)) // Don't enumerate BB operand to BlockAddress.
+          EnumerateValue(*I);
+
+      // Finally, add the value.  Doing this could make the ValueID reference be
+      // dangling, don't reuse it.
+      Values.push_back(std::make_pair(V, 1U));
+      ValueMap[V] = Values.size();
+      return;
+    }
+  }
+
+  // Add the value.
+  Values.push_back(std::make_pair(V, 1U));
+  ValueID = Values.size();
+}
+
+
+void ValueEnumerator::EnumerateType(Type *Ty) {
+  unsigned *TypeID = &TypeMap[Ty];
+
+  // We've already seen this type.
+  if (*TypeID)
+    return;
+
+  // If it is a non-anonymous struct, mark the type as being visited so that we
+  // don't recursively visit it.  This is safe because we allow forward
+  // references of these in the bitcode reader.
+  if (StructType *STy = dyn_cast<StructType>(Ty))
+    if (!STy->isLiteral())
+      *TypeID = ~0U;
+
+  // Enumerate all of the subtypes before we enumerate this type.  This ensures
+  // that the type will be enumerated in an order that can be directly built.
+  for (Type::subtype_iterator I = Ty->subtype_begin(), E = Ty->subtype_end();
+       I != E; ++I)
+    EnumerateType(*I);
+
+  // Refresh the TypeID pointer in case the table rehashed.
+  TypeID = &TypeMap[Ty];
+
+  // Check to see if we got the pointer another way.  This can happen when
+  // enumerating recursive types that hit the base case deeper than they start.
+  //
+  // If this is actually a struct that we are treating as forward ref'able,
+  // then emit the definition now that all of its contents are available.
+  if (*TypeID && *TypeID != ~0U)
+    return;
+
+  // Add this type now that its contents are all happily enumerated.
+  Types.push_back(Ty);
+
+  *TypeID = Types.size();
+}
+
+// Enumerate the types for the specified value.  If the value is a constant,
+// walk through it, enumerating the types of the constant.
+void ValueEnumerator::EnumerateOperandType(const Value *V) {
+  EnumerateType(V->getType());
+
+  if (const Constant *C = dyn_cast<Constant>(V)) {
+    // If this constant is already enumerated, ignore it, we know its type must
+    // be enumerated.
+    if (ValueMap.count(V)) return;
+
+    // This constant may have operands, make sure to enumerate the types in
+    // them.
+    for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i) {
+      const Value *Op = C->getOperand(i);
+
+      // Don't enumerate basic blocks here, this happens as operands to
+      // blockaddress.
+      if (isa<BasicBlock>(Op)) continue;
+
+      EnumerateOperandType(Op);
+    }
+
+    if (const MDNode *N = dyn_cast<MDNode>(V)) {
+      for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
+        if (Value *Elem = N->getOperand(i))
+          EnumerateOperandType(Elem);
+    }
+  } else if (isa<MDString>(V) || isa<MDNode>(V))
+    EnumerateMetadata(V);
+}
+
+void ValueEnumerator::EnumerateAttributes(AttributeSet PAL) {
+  if (PAL.isEmpty()) return;  // null is always 0.
+
+  // Do a lookup.
+  unsigned &Entry = AttributeMap[PAL];
+  if (Entry == 0) {
+    // Never saw this before, add it.
+    Attribute.push_back(PAL);
+    Entry = Attribute.size();
+  }
+
+  // Do lookups for all attribute groups.
+  for (unsigned i = 0, e = PAL.getNumSlots(); i != e; ++i) {
+    AttributeSet AS = PAL.getSlotAttributes(i);
+    unsigned &Entry = AttributeGroupMap[AS];
+    if (Entry == 0) {
+      AttributeGroups.push_back(AS);
+      Entry = AttributeGroups.size();
+    }
+  }
+}
+
+void ValueEnumerator::incorporateFunction(const Function &F) {
+  InstructionCount = 0;
+  NumModuleValues = Values.size();
+  NumModuleMDValues = MDValues.size();
+
+  // Adding function arguments to the value table.
+  for (Function::const_arg_iterator I = F.arg_begin(), E = F.arg_end();
+       I != E; ++I)
+    EnumerateValue(I);
+
+  FirstFuncConstantID = Values.size();
+
+  // Add all function-level constants to the value table.
+  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
+    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E; ++I)
+      for (User::const_op_iterator OI = I->op_begin(), E = I->op_end();
+           OI != E; ++OI) {
+        if ((isa<Constant>(*OI) && !isa<GlobalValue>(*OI)) ||
+            isa<InlineAsm>(*OI))
+          EnumerateValue(*OI);
+      }
+    BasicBlocks.push_back(BB);
+    ValueMap[BB] = BasicBlocks.size();
+  }
+
+  // Optimize the constant layout.
+  OptimizeConstants(FirstFuncConstantID, Values.size());
+
+  // Add the function's parameter attributes so they are available for use in
+  // the function's instruction.
+  EnumerateAttributes(F.getAttributes());
+
+  FirstInstID = Values.size();
+
+  SmallVector<MDNode *, 8> FnLocalMDVector;
+  // Add all of the instructions.
+  for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
+    for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I!=E; ++I) {
+      for (User::const_op_iterator OI = I->op_begin(), E = I->op_end();
+           OI != E; ++OI) {
+        if (MDNode *MD = dyn_cast<MDNode>(*OI))
+          if (MD->isFunctionLocal() && MD->getFunction())
+            // Enumerate metadata after the instructions they might refer to.
+            FnLocalMDVector.push_back(MD);
+      }
+
+      SmallVector<std::pair<unsigned, MDNode*>, 8> MDs;
+      I->getAllMetadataOtherThanDebugLoc(MDs);
+      for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
+        MDNode *N = MDs[i].second;
+        if (N->isFunctionLocal() && N->getFunction())
+          FnLocalMDVector.push_back(N);
+      }
+
+      if (!I->getType()->isVoidTy())
+        EnumerateValue(I);
+    }
+  }
+
+  // Add all of the function-local metadata.
+  for (unsigned i = 0, e = FnLocalMDVector.size(); i != e; ++i)
+    EnumerateFunctionLocalMetadata(FnLocalMDVector[i]);
+}
+
+void ValueEnumerator::purgeFunction() {
+  /// Remove purged values from the ValueMap.
+  for (unsigned i = NumModuleValues, e = Values.size(); i != e; ++i)
+    ValueMap.erase(Values[i].first);
+  for (unsigned i = NumModuleMDValues, e = MDValues.size(); i != e; ++i)
+    MDValueMap.erase(MDValues[i].first);
+  for (unsigned i = 0, e = BasicBlocks.size(); i != e; ++i)
+    ValueMap.erase(BasicBlocks[i]);
+
+  Values.resize(NumModuleValues);
+  MDValues.resize(NumModuleMDValues);
+  BasicBlocks.clear();
+  FunctionLocalMDs.clear();
+}
+
+static void IncorporateFunctionInfoGlobalBBIDs(const Function *F,
+                                 DenseMap<const BasicBlock*, unsigned> &IDMap) {
+  unsigned Counter = 0;
+  for (Function::const_iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
+    IDMap[BB] = ++Counter;
+}
+
+/// getGlobalBasicBlockID - This returns the function-specific ID for the
+/// specified basic block.  This is relatively expensive information, so it
+/// should only be used by rare constructs such as address-of-label.
+unsigned ValueEnumerator::getGlobalBasicBlockID(const BasicBlock *BB) const {
+  unsigned &Idx = GlobalBasicBlockIDs[BB];
+  if (Idx != 0)
+    return Idx-1;
+
+  IncorporateFunctionInfoGlobalBBIDs(BB->getParent(), GlobalBasicBlockIDs);
+  return getGlobalBasicBlockID(BB);
+}
+