1 //===-- llvm/CodeGen/MachineModuleInfo.cpp ----------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/CodeGen/MachineModuleInfo.h"
11 #include "llvm/ADT/PointerUnion.h"
12 #include "llvm/Analysis/ValueTracking.h"
13 #include "llvm/CodeGen/MachineFunction.h"
14 #include "llvm/CodeGen/MachineFunctionPass.h"
15 #include "llvm/CodeGen/Passes.h"
16 #include "llvm/IR/Constants.h"
17 #include "llvm/IR/DerivedTypes.h"
18 #include "llvm/IR/GlobalVariable.h"
19 #include "llvm/IR/Module.h"
20 #include "llvm/MC/MCObjectFileInfo.h"
21 #include "llvm/MC/MCSymbol.h"
22 #include "llvm/Support/Dwarf.h"
23 #include "llvm/Support/ErrorHandling.h"
25 using namespace llvm::dwarf;
27 // Handle the Pass registration stuff necessary to use DataLayout's.
28 INITIALIZE_PASS(MachineModuleInfo, "machinemoduleinfo",
29 "Machine Module Information", false, false)
30 char MachineModuleInfo::ID = 0;
32 // Out of line virtual method.
33 MachineModuleInfoImpl::~MachineModuleInfoImpl() {}
36 class MMIAddrLabelMapCallbackPtr : CallbackVH {
39 MMIAddrLabelMapCallbackPtr() : Map(nullptr) {}
40 MMIAddrLabelMapCallbackPtr(Value *V) : CallbackVH(V), Map(nullptr) {}
42 void setPtr(BasicBlock *BB) {
43 ValueHandleBase::operator=(BB);
46 void setMap(MMIAddrLabelMap *map) { Map = map; }
48 void deleted() override;
49 void allUsesReplacedWith(Value *V2) override;
52 class MMIAddrLabelMap {
54 struct AddrLabelSymEntry {
55 /// Symbols - The symbols for the label. This is a pointer union that is
56 /// either one symbol (the common case) or a list of symbols.
57 PointerUnion<MCSymbol *, std::vector<MCSymbol*>*> Symbols;
59 Function *Fn; // The containing function of the BasicBlock.
60 unsigned Index; // The index in BBCallbacks for the BasicBlock.
63 DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry> AddrLabelSymbols;
65 /// BBCallbacks - Callbacks for the BasicBlock's that we have entries for. We
66 /// use this so we get notified if a block is deleted or RAUWd.
67 std::vector<MMIAddrLabelMapCallbackPtr> BBCallbacks;
69 /// DeletedAddrLabelsNeedingEmission - This is a per-function list of symbols
70 /// whose corresponding BasicBlock got deleted. These symbols need to be
71 /// emitted at some point in the file, so AsmPrinter emits them after the
73 DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >
74 DeletedAddrLabelsNeedingEmission;
77 MMIAddrLabelMap(MCContext &context) : Context(context) {}
79 assert(DeletedAddrLabelsNeedingEmission.empty() &&
80 "Some labels for deleted blocks never got emitted");
82 // Deallocate any of the 'list of symbols' case.
83 for (DenseMap<AssertingVH<BasicBlock>, AddrLabelSymEntry>::iterator
84 I = AddrLabelSymbols.begin(), E = AddrLabelSymbols.end(); I != E; ++I)
85 if (I->second.Symbols.is<std::vector<MCSymbol*>*>())
86 delete I->second.Symbols.get<std::vector<MCSymbol*>*>();
89 MCSymbol *getAddrLabelSymbol(BasicBlock *BB);
90 std::vector<MCSymbol*> getAddrLabelSymbolToEmit(BasicBlock *BB);
92 void takeDeletedSymbolsForFunction(Function *F,
93 std::vector<MCSymbol*> &Result);
95 void UpdateForDeletedBlock(BasicBlock *BB);
96 void UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New);
100 MCSymbol *MMIAddrLabelMap::getAddrLabelSymbol(BasicBlock *BB) {
101 assert(BB->hasAddressTaken() &&
102 "Shouldn't get label for block without address taken");
103 AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
105 // If we already had an entry for this block, just return it.
106 if (!Entry.Symbols.isNull()) {
107 assert(BB->getParent() == Entry.Fn && "Parent changed");
108 if (Entry.Symbols.is<MCSymbol*>())
109 return Entry.Symbols.get<MCSymbol*>();
110 return (*Entry.Symbols.get<std::vector<MCSymbol*>*>())[0];
113 // Otherwise, this is a new entry, create a new symbol for it and add an
114 // entry to BBCallbacks so we can be notified if the BB is deleted or RAUWd.
115 BBCallbacks.push_back(BB);
116 BBCallbacks.back().setMap(this);
117 Entry.Index = BBCallbacks.size()-1;
118 Entry.Fn = BB->getParent();
119 MCSymbol *Result = Context.CreateTempSymbol();
120 Entry.Symbols = Result;
124 std::vector<MCSymbol*>
125 MMIAddrLabelMap::getAddrLabelSymbolToEmit(BasicBlock *BB) {
126 assert(BB->hasAddressTaken() &&
127 "Shouldn't get label for block without address taken");
128 AddrLabelSymEntry &Entry = AddrLabelSymbols[BB];
130 std::vector<MCSymbol*> Result;
132 // If we already had an entry for this block, just return it.
133 if (Entry.Symbols.isNull())
134 Result.push_back(getAddrLabelSymbol(BB));
135 else if (MCSymbol *Sym = Entry.Symbols.dyn_cast<MCSymbol*>())
136 Result.push_back(Sym);
138 Result = *Entry.Symbols.get<std::vector<MCSymbol*>*>();
143 /// takeDeletedSymbolsForFunction - If we have any deleted symbols for F, return
145 void MMIAddrLabelMap::
146 takeDeletedSymbolsForFunction(Function *F, std::vector<MCSymbol*> &Result) {
147 DenseMap<AssertingVH<Function>, std::vector<MCSymbol*> >::iterator I =
148 DeletedAddrLabelsNeedingEmission.find(F);
150 // If there are no entries for the function, just return.
151 if (I == DeletedAddrLabelsNeedingEmission.end()) return;
153 // Otherwise, take the list.
154 std::swap(Result, I->second);
155 DeletedAddrLabelsNeedingEmission.erase(I);
159 void MMIAddrLabelMap::UpdateForDeletedBlock(BasicBlock *BB) {
160 // If the block got deleted, there is no need for the symbol. If the symbol
161 // was already emitted, we can just forget about it, otherwise we need to
162 // queue it up for later emission when the function is output.
163 AddrLabelSymEntry Entry = AddrLabelSymbols[BB];
164 AddrLabelSymbols.erase(BB);
165 assert(!Entry.Symbols.isNull() && "Didn't have a symbol, why a callback?");
166 BBCallbacks[Entry.Index] = nullptr; // Clear the callback.
168 assert((BB->getParent() == nullptr || BB->getParent() == Entry.Fn) &&
169 "Block/parent mismatch");
171 // Handle both the single and the multiple symbols cases.
172 if (MCSymbol *Sym = Entry.Symbols.dyn_cast<MCSymbol*>()) {
173 if (Sym->isDefined())
176 // If the block is not yet defined, we need to emit it at the end of the
177 // function. Add the symbol to the DeletedAddrLabelsNeedingEmission list
178 // for the containing Function. Since the block is being deleted, its
179 // parent may already be removed, we have to get the function from 'Entry'.
180 DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(Sym);
182 std::vector<MCSymbol*> *Syms = Entry.Symbols.get<std::vector<MCSymbol*>*>();
184 for (unsigned i = 0, e = Syms->size(); i != e; ++i) {
185 MCSymbol *Sym = (*Syms)[i];
186 if (Sym->isDefined()) continue; // Ignore already emitted labels.
188 // If the block is not yet defined, we need to emit it at the end of the
189 // function. Add the symbol to the DeletedAddrLabelsNeedingEmission list
190 // for the containing Function. Since the block is being deleted, its
191 // parent may already be removed, we have to get the function from
193 DeletedAddrLabelsNeedingEmission[Entry.Fn].push_back(Sym);
196 // The entry is deleted, free the memory associated with the symbol list.
201 void MMIAddrLabelMap::UpdateForRAUWBlock(BasicBlock *Old, BasicBlock *New) {
202 // Get the entry for the RAUW'd block and remove it from our map.
203 AddrLabelSymEntry OldEntry = AddrLabelSymbols[Old];
204 AddrLabelSymbols.erase(Old);
205 assert(!OldEntry.Symbols.isNull() && "Didn't have a symbol, why a callback?");
207 AddrLabelSymEntry &NewEntry = AddrLabelSymbols[New];
209 // If New is not address taken, just move our symbol over to it.
210 if (NewEntry.Symbols.isNull()) {
211 BBCallbacks[OldEntry.Index].setPtr(New); // Update the callback.
212 NewEntry = OldEntry; // Set New's entry.
216 BBCallbacks[OldEntry.Index] = nullptr; // Update the callback.
218 // Otherwise, we need to add the old symbol to the new block's set. If it is
219 // just a single entry, upgrade it to a symbol list.
220 if (MCSymbol *PrevSym = NewEntry.Symbols.dyn_cast<MCSymbol*>()) {
221 std::vector<MCSymbol*> *SymList = new std::vector<MCSymbol*>();
222 SymList->push_back(PrevSym);
223 NewEntry.Symbols = SymList;
226 std::vector<MCSymbol*> *SymList =
227 NewEntry.Symbols.get<std::vector<MCSymbol*>*>();
229 // If the old entry was a single symbol, add it.
230 if (MCSymbol *Sym = OldEntry.Symbols.dyn_cast<MCSymbol*>()) {
231 SymList->push_back(Sym);
235 // Otherwise, concatenate the list.
236 std::vector<MCSymbol*> *Syms =OldEntry.Symbols.get<std::vector<MCSymbol*>*>();
237 SymList->insert(SymList->end(), Syms->begin(), Syms->end());
242 void MMIAddrLabelMapCallbackPtr::deleted() {
243 Map->UpdateForDeletedBlock(cast<BasicBlock>(getValPtr()));
246 void MMIAddrLabelMapCallbackPtr::allUsesReplacedWith(Value *V2) {
247 Map->UpdateForRAUWBlock(cast<BasicBlock>(getValPtr()), cast<BasicBlock>(V2));
251 //===----------------------------------------------------------------------===//
253 MachineModuleInfo::MachineModuleInfo(const MCAsmInfo &MAI,
254 const MCRegisterInfo &MRI,
255 const MCObjectFileInfo *MOFI)
256 : ImmutablePass(ID), Context(&MAI, &MRI, MOFI, nullptr, false) {
257 initializeMachineModuleInfoPass(*PassRegistry::getPassRegistry());
260 MachineModuleInfo::MachineModuleInfo()
261 : ImmutablePass(ID), Context(nullptr, nullptr, nullptr) {
262 llvm_unreachable("This MachineModuleInfo constructor should never be called, "
263 "MMI should always be explicitly constructed by "
264 "LLVMTargetMachine");
267 MachineModuleInfo::~MachineModuleInfo() {
270 bool MachineModuleInfo::doInitialization(Module &M) {
272 ObjFileMMI = nullptr;
276 DbgInfoAvailable = UsesVAFloatArgument = false;
277 // Always emit some info, by default "no personality" info.
278 Personalities.push_back(nullptr);
279 AddrLabelSymbols = nullptr;
285 bool MachineModuleInfo::doFinalization(Module &M) {
287 Personalities.clear();
289 delete AddrLabelSymbols;
290 AddrLabelSymbols = nullptr;
295 ObjFileMMI = nullptr;
300 /// EndFunction - Discard function meta information.
302 void MachineModuleInfo::EndFunction() {
303 // Clean up frame info.
304 FrameInstructions.clear();
306 // Clean up exception info.
314 VariableDbgInfos.clear();
317 /// AnalyzeModule - Scan the module for global debug information.
319 void MachineModuleInfo::AnalyzeModule(const Module &M) {
320 // Insert functions in the llvm.used array (but not llvm.compiler.used) into
322 const GlobalVariable *GV = M.getGlobalVariable("llvm.used");
323 if (!GV || !GV->hasInitializer()) return;
325 // Should be an array of 'i8*'.
326 const ConstantArray *InitList = cast<ConstantArray>(GV->getInitializer());
328 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
329 if (const Function *F =
330 dyn_cast<Function>(InitList->getOperand(i)->stripPointerCasts()))
331 UsedFunctions.insert(F);
334 //===- Address of Block Management ----------------------------------------===//
337 /// getAddrLabelSymbol - Return the symbol to be used for the specified basic
338 /// block when its address is taken. This cannot be its normal LBB label
339 /// because the block may be accessed outside its containing function.
340 MCSymbol *MachineModuleInfo::getAddrLabelSymbol(const BasicBlock *BB) {
341 // Lazily create AddrLabelSymbols.
342 if (!AddrLabelSymbols)
343 AddrLabelSymbols = new MMIAddrLabelMap(Context);
344 return AddrLabelSymbols->getAddrLabelSymbol(const_cast<BasicBlock*>(BB));
347 /// getAddrLabelSymbolToEmit - Return the symbol to be used for the specified
348 /// basic block when its address is taken. If other blocks were RAUW'd to
349 /// this one, we may have to emit them as well, return the whole set.
350 std::vector<MCSymbol*> MachineModuleInfo::
351 getAddrLabelSymbolToEmit(const BasicBlock *BB) {
352 // Lazily create AddrLabelSymbols.
353 if (!AddrLabelSymbols)
354 AddrLabelSymbols = new MMIAddrLabelMap(Context);
355 return AddrLabelSymbols->getAddrLabelSymbolToEmit(const_cast<BasicBlock*>(BB));
359 /// takeDeletedSymbolsForFunction - If the specified function has had any
360 /// references to address-taken blocks generated, but the block got deleted,
361 /// return the symbol now so we can emit it. This prevents emitting a
362 /// reference to a symbol that has no definition.
363 void MachineModuleInfo::
364 takeDeletedSymbolsForFunction(const Function *F,
365 std::vector<MCSymbol*> &Result) {
366 // If no blocks have had their addresses taken, we're done.
367 if (!AddrLabelSymbols) return;
368 return AddrLabelSymbols->
369 takeDeletedSymbolsForFunction(const_cast<Function*>(F), Result);
372 //===- EH -----------------------------------------------------------------===//
374 /// getOrCreateLandingPadInfo - Find or create an LandingPadInfo for the
375 /// specified MachineBasicBlock.
376 LandingPadInfo &MachineModuleInfo::getOrCreateLandingPadInfo
377 (MachineBasicBlock *LandingPad) {
378 unsigned N = LandingPads.size();
379 for (unsigned i = 0; i < N; ++i) {
380 LandingPadInfo &LP = LandingPads[i];
381 if (LP.LandingPadBlock == LandingPad)
385 LandingPads.push_back(LandingPadInfo(LandingPad));
386 return LandingPads[N];
389 /// addInvoke - Provide the begin and end labels of an invoke style call and
390 /// associate it with a try landing pad block.
391 void MachineModuleInfo::addInvoke(MachineBasicBlock *LandingPad,
392 MCSymbol *BeginLabel, MCSymbol *EndLabel) {
393 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
394 LP.BeginLabels.push_back(BeginLabel);
395 LP.EndLabels.push_back(EndLabel);
398 /// addLandingPad - Provide the label of a try LandingPad block.
400 MCSymbol *MachineModuleInfo::addLandingPad(MachineBasicBlock *LandingPad) {
401 MCSymbol *LandingPadLabel = Context.CreateTempSymbol();
402 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
403 LP.LandingPadLabel = LandingPadLabel;
404 return LandingPadLabel;
407 /// addPersonality - Provide the personality function for the exception
409 void MachineModuleInfo::addPersonality(MachineBasicBlock *LandingPad,
410 const Function *Personality) {
411 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
412 LP.Personality = Personality;
414 for (unsigned i = 0; i < Personalities.size(); ++i)
415 if (Personalities[i] == Personality)
418 // If this is the first personality we're adding go
419 // ahead and add it at the beginning.
420 if (!Personalities[0])
421 Personalities[0] = Personality;
423 Personalities.push_back(Personality);
426 /// addCatchTypeInfo - Provide the catch typeinfo for a landing pad.
428 void MachineModuleInfo::
429 addCatchTypeInfo(MachineBasicBlock *LandingPad,
430 ArrayRef<const GlobalVariable *> TyInfo) {
431 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
432 for (unsigned N = TyInfo.size(); N; --N)
433 LP.TypeIds.push_back(getTypeIDFor(TyInfo[N - 1]));
436 /// addFilterTypeInfo - Provide the filter typeinfo for a landing pad.
438 void MachineModuleInfo::
439 addFilterTypeInfo(MachineBasicBlock *LandingPad,
440 ArrayRef<const GlobalVariable *> TyInfo) {
441 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
442 std::vector<unsigned> IdsInFilter(TyInfo.size());
443 for (unsigned I = 0, E = TyInfo.size(); I != E; ++I)
444 IdsInFilter[I] = getTypeIDFor(TyInfo[I]);
445 LP.TypeIds.push_back(getFilterIDFor(IdsInFilter));
448 /// addCleanup - Add a cleanup action for a landing pad.
450 void MachineModuleInfo::addCleanup(MachineBasicBlock *LandingPad) {
451 LandingPadInfo &LP = getOrCreateLandingPadInfo(LandingPad);
452 LP.TypeIds.push_back(0);
455 /// TidyLandingPads - Remap landing pad labels and remove any deleted landing
457 void MachineModuleInfo::TidyLandingPads(DenseMap<MCSymbol*, uintptr_t> *LPMap) {
458 for (unsigned i = 0; i != LandingPads.size(); ) {
459 LandingPadInfo &LandingPad = LandingPads[i];
460 if (LandingPad.LandingPadLabel &&
461 !LandingPad.LandingPadLabel->isDefined() &&
462 (!LPMap || (*LPMap)[LandingPad.LandingPadLabel] == 0))
463 LandingPad.LandingPadLabel = nullptr;
465 // Special case: we *should* emit LPs with null LP MBB. This indicates
467 if (!LandingPad.LandingPadLabel && LandingPad.LandingPadBlock) {
468 LandingPads.erase(LandingPads.begin() + i);
472 for (unsigned j = 0, e = LandingPads[i].BeginLabels.size(); j != e; ++j) {
473 MCSymbol *BeginLabel = LandingPad.BeginLabels[j];
474 MCSymbol *EndLabel = LandingPad.EndLabels[j];
475 if ((BeginLabel->isDefined() ||
476 (LPMap && (*LPMap)[BeginLabel] != 0)) &&
477 (EndLabel->isDefined() ||
478 (LPMap && (*LPMap)[EndLabel] != 0))) continue;
480 LandingPad.BeginLabels.erase(LandingPad.BeginLabels.begin() + j);
481 LandingPad.EndLabels.erase(LandingPad.EndLabels.begin() + j);
485 // Remove landing pads with no try-ranges.
486 if (LandingPads[i].BeginLabels.empty()) {
487 LandingPads.erase(LandingPads.begin() + i);
491 // If there is no landing pad, ensure that the list of typeids is empty.
492 // If the only typeid is a cleanup, this is the same as having no typeids.
493 if (!LandingPad.LandingPadBlock ||
494 (LandingPad.TypeIds.size() == 1 && !LandingPad.TypeIds[0]))
495 LandingPad.TypeIds.clear();
500 /// setCallSiteLandingPad - Map the landing pad's EH symbol to the call site
502 void MachineModuleInfo::setCallSiteLandingPad(MCSymbol *Sym,
503 ArrayRef<unsigned> Sites) {
504 LPadToCallSiteMap[Sym].append(Sites.begin(), Sites.end());
507 /// getTypeIDFor - Return the type id for the specified typeinfo. This is
509 unsigned MachineModuleInfo::getTypeIDFor(const GlobalVariable *TI) {
510 for (unsigned i = 0, N = TypeInfos.size(); i != N; ++i)
511 if (TypeInfos[i] == TI) return i + 1;
513 TypeInfos.push_back(TI);
514 return TypeInfos.size();
517 /// getFilterIDFor - Return the filter id for the specified typeinfos. This is
519 int MachineModuleInfo::getFilterIDFor(std::vector<unsigned> &TyIds) {
520 // If the new filter coincides with the tail of an existing filter, then
521 // re-use the existing filter. Folding filters more than this requires
522 // re-ordering filters and/or their elements - probably not worth it.
523 for (std::vector<unsigned>::iterator I = FilterEnds.begin(),
524 E = FilterEnds.end(); I != E; ++I) {
525 unsigned i = *I, j = TyIds.size();
528 if (FilterIds[--i] != TyIds[--j])
532 // The new filter coincides with range [i, end) of the existing filter.
538 // Add the new filter.
539 int FilterID = -(1 + FilterIds.size());
540 FilterIds.reserve(FilterIds.size() + TyIds.size() + 1);
541 FilterIds.insert(FilterIds.end(), TyIds.begin(), TyIds.end());
542 FilterEnds.push_back(FilterIds.size());
543 FilterIds.push_back(0); // terminator
547 /// getPersonality - Return the personality function for the current function.
548 const Function *MachineModuleInfo::getPersonality() const {
549 // FIXME: Until PR1414 will be fixed, we're using 1 personality function per
551 return !LandingPads.empty() ? LandingPads[0].Personality : nullptr;
554 /// getPersonalityIndex - Return unique index for current personality
555 /// function. NULL/first personality function should always get zero index.
556 unsigned MachineModuleInfo::getPersonalityIndex() const {
557 const Function* Personality = nullptr;
559 // Scan landing pads. If there is at least one non-NULL personality - use it.
560 for (unsigned i = 0, e = LandingPads.size(); i != e; ++i)
561 if (LandingPads[i].Personality) {
562 Personality = LandingPads[i].Personality;
566 for (unsigned i = 0, e = Personalities.size(); i < e; ++i) {
567 if (Personalities[i] == Personality)
571 // This will happen if the current personality function is
572 // in the zero index.