//===-- 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/DebugInfoMetadata.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/UseListOrder.h"
#include "llvm/IR/ValueSymbolTable.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
using namespace llvm;
namespace {
struct OrderMap {
DenseMap<const Value *, std::pair<unsigned, bool>> IDs;
unsigned LastGlobalConstantID;
unsigned LastGlobalValueID;
OrderMap() : LastGlobalConstantID(0), LastGlobalValueID(0) {}
bool isGlobalConstant(unsigned ID) const {
return ID <= LastGlobalConstantID;
}
bool isGlobalValue(unsigned ID) const {
return ID <= LastGlobalValueID && !isGlobalConstant(ID);
}
unsigned size() const { return IDs.size(); }
std::pair<unsigned, bool> &operator[](const Value *V) { return IDs[V]; }
std::pair<unsigned, bool> lookup(const Value *V) const {
return IDs.lookup(V);
}
void index(const Value *V) {
// Explicitly sequence get-size and insert-value operations to avoid UB.
unsigned ID = IDs.size() + 1;
IDs[V].first = ID;
}
};
}
static void orderValue(const Value *V, OrderMap &OM) {
if (OM.lookup(V).first)
return;
if (const Constant *C = dyn_cast<Constant>(V))
if (C->getNumOperands() && !isa<GlobalValue>(C))
for (const Value *Op : C->operands())
if (!isa<BasicBlock>(Op) && !isa<GlobalValue>(Op))
orderValue(Op, OM);
// Note: we cannot cache this lookup above, since inserting into the map
// changes the map's size, and thus affects the other IDs.
OM.index(V);
}
static OrderMap orderModule(const Module &M) {
// This needs to match the order used by ValueEnumerator::ValueEnumerator()
// and ValueEnumerator::incorporateFunction().
OrderMap OM;
// In the reader, initializers of GlobalValues are set *after* all the
// globals have been read. Rather than awkwardly modeling this behaviour
// directly in predictValueUseListOrderImpl(), just assign IDs to
// initializers of GlobalValues before GlobalValues themselves to model this
// implicitly.
for (const GlobalVariable &G : M.globals())
if (G.hasInitializer())
if (!isa<GlobalValue>(G.getInitializer()))
orderValue(G.getInitializer(), OM);
for (const GlobalAlias &A : M.aliases())
if (!isa<GlobalValue>(A.getAliasee()))
orderValue(A.getAliasee(), OM);
for (const Function &F : M) {
for (const Use &U : F.operands())
if (!isa<GlobalValue>(U.get()))
orderValue(U.get(), OM);
}
OM.LastGlobalConstantID = OM.size();
// Initializers of GlobalValues are processed in
// BitcodeReader::ResolveGlobalAndAliasInits(). Match the order there rather
// than ValueEnumerator, and match the code in predictValueUseListOrderImpl()
// by giving IDs in reverse order.
//
// Since GlobalValues never reference each other directly (just through
// initializers), their relative IDs only matter for determining order of
// uses in their initializers.
for (const Function &F : M)
orderValue(&F, OM);
for (const GlobalAlias &A : M.aliases())
orderValue(&A, OM);
for (const GlobalVariable &G : M.globals())
orderValue(&G, OM);
OM.LastGlobalValueID = OM.size();
for (const Function &F : M) {
if (F.isDeclaration())
continue;
// Here we need to match the union of ValueEnumerator::incorporateFunction()
// and WriteFunction(). Basic blocks are implicitly declared before
// anything else (by declaring their size).
for (const BasicBlock &BB : F)
orderValue(&BB, OM);
for (const Argument &A : F.args())
orderValue(&A, OM);
for (const BasicBlock &BB : F)
for (const Instruction &I : BB)
for (const Value *Op : I.operands())
if ((isa<Constant>(*Op) && !isa<GlobalValue>(*Op)) ||
isa<InlineAsm>(*Op))
orderValue(Op, OM);
for (const BasicBlock &BB : F)
for (const Instruction &I : BB)
orderValue(&I, OM);
}
return OM;
}
static void predictValueUseListOrderImpl(const Value *V, const Function *F,
unsigned ID, const OrderMap &OM,
UseListOrderStack &Stack) {
// Predict use-list order for this one.
typedef std::pair<const Use *, unsigned> Entry;
SmallVector<Entry, 64> List;
for (const Use &U : V->uses())
// Check if this user will be serialized.
if (OM.lookup(U.getUser()).first)
List.push_back(std::make_pair(&U, List.size()));
if (List.size() < 2)
// We may have lost some users.
return;
bool IsGlobalValue = OM.isGlobalValue(ID);
std::sort(List.begin(), List.end(), [&](const Entry &L, const Entry &R) {
const Use *LU = L.first;
const Use *RU = R.first;
if (LU == RU)
return false;
auto LID = OM.lookup(LU->getUser()).first;
auto RID = OM.lookup(RU->getUser()).first;
// Global values are processed in reverse order.
//
// Moreover, initializers of GlobalValues are set *after* all the globals
// have been read (despite having earlier IDs). Rather than awkwardly
// modeling this behaviour here, orderModule() has assigned IDs to
// initializers of GlobalValues before GlobalValues themselves.
if (OM.isGlobalValue(LID) && OM.isGlobalValue(RID))
return LID < RID;
// If ID is 4, then expect: 7 6 5 1 2 3.
if (LID < RID) {
if (RID <= ID)
if (!IsGlobalValue) // GlobalValue uses don't get reversed.
return true;
return false;
}
if (RID < LID) {
if (LID <= ID)
if (!IsGlobalValue) // GlobalValue uses don't get reversed.
return false;
return true;
}
// LID and RID are equal, so we have different operands of the same user.
// Assume operands are added in order for all instructions.
if (LID <= ID)
if (!IsGlobalValue) // GlobalValue uses don't get reversed.
return LU->getOperandNo() < RU->getOperandNo();
return LU->getOperandNo() > RU->getOperandNo();
});
if (std::is_sorted(
List.begin(), List.end(),
[](const Entry &L, const Entry &R) { return L.second < R.second; }))
// Order is already correct.
return;
// Store the shuffle.
Stack.emplace_back(V, F, List.size());
assert(List.size() == Stack.back().Shuffle.size() && "Wrong size");
for (size_t I = 0, E = List.size(); I != E; ++I)
Stack.back().Shuffle[I] = List[I].second;
}
static void predictValueUseListOrder(const Value *V, const Function *F,
OrderMap &OM, UseListOrderStack &Stack) {
auto &IDPair = OM[V];
assert(IDPair.first && "Unmapped value");
if (IDPair.second)
// Already predicted.
return;
// Do the actual prediction.
IDPair.second = true;
if (!V->use_empty() && std::next(V->use_begin()) != V->use_end())
predictValueUseListOrderImpl(V, F, IDPair.first, OM, Stack);
// Recursive descent into constants.
if (const Constant *C = dyn_cast<Constant>(V))
if (C->getNumOperands()) // Visit GlobalValues.
for (const Value *Op : C->operands())
if (isa<Constant>(Op)) // Visit GlobalValues.
predictValueUseListOrder(Op, F, OM, Stack);
}
static UseListOrderStack predictUseListOrder(const Module &M) {
OrderMap OM = orderModule(M);
// Use-list orders need to be serialized after all the users have been added
// to a value, or else the shuffles will be incomplete. Store them per
// function in a stack.
//
// Aside from function order, the order of values doesn't matter much here.
UseListOrderStack Stack;
// We want to visit the functions backward now so we can list function-local
// constants in the last Function they're used in. Module-level constants
// have already been visited above.
for (auto I = M.rbegin(), E = M.rend(); I != E; ++I) {
const Function &F = *I;
if (F.isDeclaration())
continue;
for (const BasicBlock &BB : F)
predictValueUseListOrder(&BB, &F, OM, Stack);
for (const Argument &A : F.args())
predictValueUseListOrder(&A, &F, OM, Stack);
for (const BasicBlock &BB : F)
for (const Instruction &I : BB)
for (const Value *Op : I.operands())
if (isa<Constant>(*Op) || isa<InlineAsm>(*Op)) // Visit GlobalValues.
predictValueUseListOrder(Op, &F, OM, Stack);
for (const BasicBlock &BB : F)
for (const Instruction &I : BB)
predictValueUseListOrder(&I, &F, OM, Stack);
}
// Visit globals last, since the module-level use-list block will be seen
// before the function bodies are processed.
for (const GlobalVariable &G : M.globals())
predictValueUseListOrder(&G, nullptr, OM, Stack);
for (const Function &F : M)
predictValueUseListOrder(&F, nullptr, OM, Stack);
for (const GlobalAlias &A : M.aliases())
predictValueUseListOrder(&A, nullptr, OM, Stack);
for (const GlobalVariable &G : M.globals())
if (G.hasInitializer())
predictValueUseListOrder(G.getInitializer(), nullptr, OM, Stack);
for (const GlobalAlias &A : M.aliases())
predictValueUseListOrder(A.getAliasee(), nullptr, OM, Stack);
for (const Function &F : M) {
for (const Use &U : F.operands())
predictValueUseListOrder(U.get(), nullptr, OM, Stack);
}
return Stack;
}
static bool isIntOrIntVectorValue(const std::pair<const Value*, unsigned> &V) {
return V.first->getType()->isIntOrIntVectorTy();
}
ValueEnumerator::ValueEnumerator(const Module &M,
bool ShouldPreserveUseListOrder)
: HasMDString(false), HasDILocation(false), HasGenericDINode(false),
ShouldPreserveUseListOrder(ShouldPreserveUseListOrder) {
if (ShouldPreserveUseListOrder)
UseListOrders = predictUseListOrder(M);
// Enumerate the global variables.
for (const GlobalVariable &GV : M.globals())
EnumerateValue(&GV);
// Enumerate the functions.
for (const Function & F : M) {
EnumerateValue(&F);
EnumerateAttributes(F.getAttributes());
}
// Enumerate the aliases.
for (const GlobalAlias &GA : M.aliases())
EnumerateValue(&GA);
// Remember what is the cutoff between globalvalue's and other constants.
unsigned FirstConstant = Values.size();
// Enumerate the global variable initializers.
for (const GlobalVariable &GV : M.globals())
if (GV.hasInitializer())
EnumerateValue(GV.getInitializer());
// Enumerate the aliasees.
for (const GlobalAlias &GA : M.aliases())
EnumerateValue(GA.getAliasee());
// Enumerate any optional Function data.
for (const Function &F : M)
for (const Use &U : F.operands())
EnumerateValue(U.get());
// Enumerate the metadata type.
//
// TODO: Move this to ValueEnumerator::EnumerateOperandType() once bitcode
// only encodes the metadata type when it's used as a value.
EnumerateType(Type::getMetadataTy(M.getContext()));
// 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 (const Function &F : M) {
for (const Argument &A : F.args())
EnumerateType(A.getType());
// Enumerate metadata attached to this function.
F.getAllMetadata(MDs);
for (const auto &I : MDs)
EnumerateMetadata(I.second);
for (const BasicBlock &BB : F)
for (const Instruction &I : BB) {
for (const Use &Op : I.operands()) {
auto *MD = dyn_cast<MetadataAsValue>(&Op);
if (!MD) {
EnumerateOperandType(Op);
continue;
}
// Local metadata is enumerated during function-incorporation.
if (isa<LocalAsMetadata>(MD->getMetadata()))
continue;
EnumerateMetadata(MD->getMetadata());
}
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);
// Don't enumerate the location directly -- it has a special record
// type -- but enumerate its operands.
if (DILocation *L = I.getDebugLoc())
EnumerateMDNodeOperands(L);
}
}
// 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;
}
unsigned ValueEnumerator::getComdatID(const Comdat *C) const {
unsigned ComdatID = Comdats.idFor(C);
assert(ComdatID && "Comdat not found!");
return ComdatID;
}
void ValueEnumerator::setInstructionID(const Instruction *I) {
InstructionMap[I] = InstructionCount++;
}
unsigned ValueEnumerator::getValueID(const Value *V) const {
if (auto *MD = dyn_cast<MetadataAsValue>(V))
return getMetadataID(MD->getMetadata());
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 (const Use &U : V->uses()) {
if (&U != &*V->use_begin())
OS << ",";
if(U->hasName())
OS << " " << U->getName();
else
OS << " [null]";
}
OS << "\n\n";
}
}
void ValueEnumerator::print(raw_ostream &OS, const MetadataMapType &Map,
const char *Name) const {
OS << "Map Name: " << Name << "\n";
OS << "Size: " << Map.size() << "\n";
for (auto I = Map.begin(), E = Map.end(); I != E; ++I) {
const Metadata *MD = I->first;
OS << "Metadata: slot = " << I->second << "\n";
MD->print(OS);
}
}
/// OptimizeConstants - Reorder constant pool for denser encoding.
void ValueEnumerator::OptimizeConstants(unsigned CstStart, unsigned CstEnd) {
if (CstStart == CstEnd || CstStart+1 == CstEnd) return;
if (ShouldPreserveUseListOrder)
// Optimizing constants makes the use-list order difficult to predict.
// Disable it for now when trying to preserve the order.
return;
std::stable_sort(Values.begin() + CstStart, Values.begin() + CstEnd,
[this](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 getTypeID(LHS.first->getType()) < getTypeID(RHS.first->getType());
// Then by frequency.
return LHS.second > RHS.second;
});
// 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());
}
/// Insert all of the values referenced by named metadata in the specified
/// module.
void ValueEnumerator::EnumerateNamedMetadata(const Module &M) {
for (const auto &I : M.named_metadata())
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) {
Metadata *MD = N->getOperand(i);
if (!MD)
continue;
assert(!isa<LocalAsMetadata>(MD) && "MDNodes cannot be function-local");
EnumerateMetadata(MD);
}
}
void ValueEnumerator::EnumerateMetadata(const Metadata *MD) {
assert(
(isa<MDNode>(MD) || isa<MDString>(MD) || isa<ConstantAsMetadata>(MD)) &&
"Invalid metadata kind");
// Insert a dummy ID to block the co-recursive call to
// EnumerateMDNodeOperands() from re-visiting MD in a cyclic graph.
//
// Return early if there's already an ID.
if (!MDValueMap.insert(std::make_pair(MD, 0)).second)
return;
// Visit operands first to minimize RAUW.
if (auto *N = dyn_cast<MDNode>(MD))
EnumerateMDNodeOperands(N);
else if (auto *C = dyn_cast<ConstantAsMetadata>(MD))
EnumerateValue(C->getValue());
HasMDString |= isa<MDString>(MD);
HasDILocation |= isa<DILocation>(MD);
HasGenericDINode |= isa<GenericDINode>(MD);
// Replace the dummy ID inserted above with the correct one. MDValueMap may
// have changed by inserting operands, so we need a fresh lookup here.
MDs.push_back(MD);
MDValueMap[MD] = MDs.size();
}
/// EnumerateFunctionLocalMetadataa - Incorporate function-local metadata
/// information reachable from the metadata.
void ValueEnumerator::EnumerateFunctionLocalMetadata(
const LocalAsMetadata *Local) {
// Check to see if it's already in!
unsigned &MDValueID = MDValueMap[Local];
if (MDValueID)
return;
MDs.push_back(Local);
MDValueID = MDs.size();
EnumerateValue(Local->getValue());
// Also, collect all function-local metadata for easy access.
FunctionLocalMDs.push_back(Local);
}
void ValueEnumerator::EnumerateValue(const Value *V) {
assert(!V->getType()->isVoidTy() && "Can't insert void values!");
assert(!isa<MetadataAsValue>(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;
}
if (auto *GO = dyn_cast<GlobalObject>(V))
if (const Comdat *C = GO->getComdat())
Comdats.insert(C);
// 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 *SubTy : Ty->subtypes())
EnumerateType(SubTy);
// 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 (auto *MD = dyn_cast<MetadataAsValue>(V)) {
assert(!isa<LocalAsMetadata>(MD->getMetadata()) &&
"Function-local metadata should be left for later");
EnumerateMetadata(MD->getMetadata());
return;
}
const Constant *C = dyn_cast<Constant>(V);
if (!C)
return;
// If this constant is already enumerated, ignore it, we know its type must
// be enumerated.
if (ValueMap.count(C))
return;
// This constant may have operands, make sure to enumerate the types in
// them.
for (const Value *Op : C->operands()) {
// Don't enumerate basic blocks here, this happens as operands to
// blockaddress.
if (isa<BasicBlock>(Op))
continue;
EnumerateOperandType(Op);
}
}
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();
NumModuleMDs = MDs.size();
// Adding function arguments to the value table.
for (const auto &I : F.args())
EnumerateValue(&I);
FirstFuncConstantID = Values.size();
// Add all function-level constants to the value table.
for (const BasicBlock &BB : F) {
for (const Instruction &I : BB)
for (const Use &OI : I.operands()) {
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<LocalAsMetadata *, 8> FnLocalMDVector;
// Add all of the instructions.
for (const BasicBlock &BB : F) {
for (const Instruction &I : BB) {
for (const Use &OI : I.operands()) {
if (auto *MD = dyn_cast<MetadataAsValue>(&OI))
if (auto *Local = dyn_cast<LocalAsMetadata>(MD->getMetadata()))
// Enumerate metadata after the instructions they might refer to.
FnLocalMDVector.push_back(Local);
}
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 = NumModuleMDs, e = MDs.size(); i != e; ++i)
MDValueMap.erase(MDs[i]);
for (unsigned i = 0, e = BasicBlocks.size(); i != e; ++i)
ValueMap.erase(BasicBlocks[i]);
Values.resize(NumModuleValues);
MDs.resize(NumModuleMDs);
BasicBlocks.clear();
FunctionLocalMDs.clear();
}
static void IncorporateFunctionInfoGlobalBBIDs(const Function *F,
DenseMap<const BasicBlock*, unsigned> &IDMap) {
unsigned Counter = 0;
for (const BasicBlock &BB : *F)
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);
}
uint64_t ValueEnumerator::computeBitsRequiredForTypeIndicies() const {
return Log2_32_Ceil(getTypes().size() + 1);
}