freebsd-dev/contrib/llvm/lib/CodeGen/MachineModuleInfo.cpp
2017-04-16 16:25:46 +00:00

341 lines
11 KiB
C++

//===-- llvm/CodeGen/MachineModuleInfo.cpp ----------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/ADT/PointerUnion.h"
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/ADT/TinyPtrVector.h"
#include "llvm/Analysis/EHPersonalities.h"
#include "llvm/Analysis/ValueTracking.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFunctionInitializer.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/MC/MCObjectFileInfo.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/Dwarf.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;
using namespace llvm::dwarf;
// Handle the Pass registration stuff necessary to use DataLayout's.
INITIALIZE_TM_PASS(MachineModuleInfo, "machinemoduleinfo",
"Machine Module Information", false, false)
char MachineModuleInfo::ID = 0;
// Out of line virtual method.
MachineModuleInfoImpl::~MachineModuleInfoImpl() {}
namespace llvm {
class MMIAddrLabelMapCallbackPtr final : CallbackVH {
MMIAddrLabelMap *Map;
public:
MMIAddrLabelMapCallbackPtr() : Map(nullptr) {}
MMIAddrLabelMapCallbackPtr(Value *V) : CallbackVH(V), Map(nullptr) {}
void setPtr(BasicBlock *BB) {
ValueHandleBase::operator=(BB);
}
void setMap(MMIAddrLabelMap *map) { Map = map; }
void deleted() override;
void allUsesReplacedWith(Value *V2) override;
};
class MMIAddrLabelMap {
MCContext &Context;
struct AddrLabelSymEntry {
/// The symbols for the label.
TinyPtrVector<MCSymbol *> Symbols;
Function *Fn; // The containing function of the BasicBlock.
unsigned Index; // The index in BBCallbacks for the BasicBlock.
};
DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry> AddrLabelSymbols;
/// Callbacks for the BasicBlock's that we have entries for. We use this so
/// we get notified if a block is deleted or RAUWd.
std::vector<MMIAddrLabelMapCallbackPtr> BBCallbacks;
/// This is a per-function list of symbols whose corresponding BasicBlock got
/// deleted. These symbols need to be emitted at some point in the file, so
/// AsmPrinter emits them after the function body.
DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >
DeletedAddrLabelsNeedingEmission;
public:
MMIAddrLabelMap(MCContext &context) : Context(context) {}
~MMIAddrLabelMap() {
assert(DeletedAddrLabelsNeedingEmission.empty() &&
"Some labels for deleted blocks never got emitted");
}
ArrayRef<MCSymbol *> getAddrLabelSymbolToEmit(BasicBlock *BB);
void takeDeletedSymbolsForFunction(Function *F,
std::vector<MCSymbol*> &Result);
void UpdateForDeletedBlock(BasicBlock *BB);
void UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New);
};
}
ArrayRef<MCSymbol *> MMIAddrLabelMap::getAddrLabelSymbolToEmit(BasicBlock *BB) {
assert(BB->hasAddressTaken() &&
"Shouldn't get label for block without address taken");
AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
// If we already had an entry for this block, just return it.
if (!Entry.Symbols.empty()) {
assert(BB->getParent() == Entry.Fn && "Parent changed");
return Entry.Symbols;
}
// Otherwise, this is a new entry, create a new symbol for it and add an
// entry to BBCallbacks so we can be notified if the BB is deleted or RAUWd.
BBCallbacks.emplace_back(BB);
BBCallbacks.back().setMap(this);
Entry.Index = BBCallbacks.size() - 1;
Entry.Fn = BB->getParent();
Entry.Symbols.push_back(Context.createTempSymbol());
return Entry.Symbols;
}
/// If we have any deleted symbols for F, return them.
void MMIAddrLabelMap::
takeDeletedSymbolsForFunction(Function *F, std::vector<MCSymbol*> &Result) {
DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >::iterator I =
DeletedAddrLabelsNeedingEmission.find(F);
// If there are no entries for the function, just return.
if (I == DeletedAddrLabelsNeedingEmission.end()) return;
// Otherwise, take the list.
std::swap(Result, I->second);
DeletedAddrLabelsNeedingEmission.erase(I);
}
void MMIAddrLabelMap::UpdateForDeletedBlock(BasicBlock *BB) {
// If the block got deleted, there is no need for the symbol. If the symbol
// was already emitted, we can just forget about it, otherwise we need to
// queue it up for later emission when the function is output.
AddrLabelSymEntry Entry = std::move(AddrLabelSymbols[BB]);
AddrLabelSymbols.erase(BB);
assert(!Entry.Symbols.empty() && "Didn't have a symbol, why a callback?");
BBCallbacks[Entry.Index] = nullptr; // Clear the callback.
assert((BB->getParent() == nullptr || BB->getParent() == Entry.Fn) &&
"Block/parent mismatch");
for (MCSymbol *Sym : Entry.Symbols) {
if (Sym->isDefined())
return;
// If the block is not yet defined, we need to emit it at the end of the
// function. Add the symbol to the DeletedAddrLabelsNeedingEmission list
// for the containing Function. Since the block is being deleted, its
// parent may already be removed, we have to get the function from 'Entry'.
DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(Sym);
}
}
void MMIAddrLabelMap::UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New) {
// Get the entry for the RAUW'd block and remove it from our map.
AddrLabelSymEntry OldEntry = std::move(AddrLabelSymbols[Old]);
AddrLabelSymbols.erase(Old);
assert(!OldEntry.Symbols.empty() && "Didn't have a symbol, why a callback?");
AddrLabelSymEntry &NewEntry = AddrLabelSymbols[New];
// If New is not address taken, just move our symbol over to it.
if (NewEntry.Symbols.empty()) {
BBCallbacks[OldEntry.Index].setPtr(New); // Update the callback.
NewEntry = std::move(OldEntry); // Set New's entry.
return;
}
BBCallbacks[OldEntry.Index] = nullptr; // Update the callback.
// Otherwise, we need to add the old symbols to the new block's set.
NewEntry.Symbols.insert(NewEntry.Symbols.end(), OldEntry.Symbols.begin(),
OldEntry.Symbols.end());
}
void MMIAddrLabelMapCallbackPtr::deleted() {
Map->UpdateForDeletedBlock(cast<BasicBlock>(getValPtr()));
}
void MMIAddrLabelMapCallbackPtr::allUsesReplacedWith(Value *V2) {
Map->UpdateForRAUWBlock(cast<BasicBlock>(getValPtr()), cast<BasicBlock>(V2));
}
//===----------------------------------------------------------------------===//
MachineModuleInfo::MachineModuleInfo(const TargetMachine *TM)
: ImmutablePass(ID), TM(*TM),
Context(TM->getMCAsmInfo(), TM->getMCRegisterInfo(),
TM->getObjFileLowering(), nullptr, false) {
initializeMachineModuleInfoPass(*PassRegistry::getPassRegistry());
}
MachineModuleInfo::~MachineModuleInfo() {
}
bool MachineModuleInfo::doInitialization(Module &M) {
ObjFileMMI = nullptr;
CurCallSite = 0;
DbgInfoAvailable = UsesVAFloatArgument = UsesMorestackAddr = false;
AddrLabelSymbols = nullptr;
TheModule = &M;
return false;
}
bool MachineModuleInfo::doFinalization(Module &M) {
Personalities.clear();
delete AddrLabelSymbols;
AddrLabelSymbols = nullptr;
Context.reset();
delete ObjFileMMI;
ObjFileMMI = nullptr;
return false;
}
//===- Address of Block Management ----------------------------------------===//
ArrayRef<MCSymbol *>
MachineModuleInfo::getAddrLabelSymbolToEmit(const BasicBlock *BB) {
// Lazily create AddrLabelSymbols.
if (!AddrLabelSymbols)
AddrLabelSymbols = new MMIAddrLabelMap(Context);
return AddrLabelSymbols->getAddrLabelSymbolToEmit(const_cast<BasicBlock*>(BB));
}
void MachineModuleInfo::
takeDeletedSymbolsForFunction(const Function *F,
std::vector<MCSymbol*> &Result) {
// If no blocks have had their addresses taken, we're done.
if (!AddrLabelSymbols) return;
return AddrLabelSymbols->
takeDeletedSymbolsForFunction(const_cast<Function*>(F), Result);
}
/// \name Exception Handling
/// \{
void MachineModuleInfo::addPersonality(const Function *Personality) {
for (unsigned i = 0; i < Personalities.size(); ++i)
if (Personalities[i] == Personality)
return;
Personalities.push_back(Personality);
}
/// \}
MachineFunction &MachineModuleInfo::getMachineFunction(const Function &F) {
// Shortcut for the common case where a sequence of MachineFunctionPasses
// all query for the same Function.
if (LastRequest == &F)
return *LastResult;
auto I = MachineFunctions.insert(
std::make_pair(&F, std::unique_ptr<MachineFunction>()));
MachineFunction *MF;
if (I.second) {
// No pre-existing machine function, create a new one.
MF = new MachineFunction(&F, TM, NextFnNum++, *this);
// Update the set entry.
I.first->second.reset(MF);
if (MFInitializer)
if (MFInitializer->initializeMachineFunction(*MF))
report_fatal_error("Unable to initialize machine function");
} else {
MF = I.first->second.get();
}
LastRequest = &F;
LastResult = MF;
return *MF;
}
void MachineModuleInfo::deleteMachineFunctionFor(Function &F) {
MachineFunctions.erase(&F);
LastRequest = nullptr;
LastResult = nullptr;
}
namespace {
/// This pass frees the MachineFunction object associated with a Function.
class FreeMachineFunction : public FunctionPass {
public:
static char ID;
FreeMachineFunction() : FunctionPass(ID) {}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<MachineModuleInfo>();
AU.addPreserved<MachineModuleInfo>();
}
bool runOnFunction(Function &F) override {
MachineModuleInfo &MMI = getAnalysis<MachineModuleInfo>();
MMI.deleteMachineFunctionFor(F);
return true;
}
StringRef getPassName() const override {
return "Free MachineFunction";
}
};
char FreeMachineFunction::ID;
} // end anonymous namespace
namespace llvm {
FunctionPass *createFreeMachineFunctionPass() {
return new FreeMachineFunction();
}
} // end namespace llvm
//===- MMI building helpers -----------------------------------------------===//
void llvm::computeUsesVAFloatArgument(const CallInst &I,
MachineModuleInfo &MMI) {
FunctionType *FT =
cast<FunctionType>(I.getCalledValue()->getType()->getContainedType(0));
if (FT->isVarArg() && !MMI.usesVAFloatArgument()) {
for (unsigned i = 0, e = I.getNumArgOperands(); i != e; ++i) {
Type *T = I.getArgOperand(i)->getType();
for (auto i : post_order(T)) {
if (i->isFloatingPointTy()) {
MMI.setUsesVAFloatArgument(true);
return;
}
}
}
}
}