1 //===-- JITEmitter.cpp - Write machine code to executable memory ----------===//
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 // This file defines a MachineCodeEmitter object that is used by the JIT to
11 // write machine code to memory and remember where relocatable values are.
13 //===----------------------------------------------------------------------===//
15 #define DEBUG_TYPE "jit"
17 #include "JITDebugRegisterer.h"
18 #include "JITDwarfEmitter.h"
19 #include "llvm/ADT/OwningPtr.h"
20 #include "llvm/Constants.h"
21 #include "llvm/Module.h"
22 #include "llvm/DerivedTypes.h"
23 #include "llvm/CodeGen/JITCodeEmitter.h"
24 #include "llvm/CodeGen/MachineFunction.h"
25 #include "llvm/CodeGen/MachineConstantPool.h"
26 #include "llvm/CodeGen/MachineJumpTableInfo.h"
27 #include "llvm/CodeGen/MachineModuleInfo.h"
28 #include "llvm/CodeGen/MachineRelocation.h"
29 #include "llvm/ExecutionEngine/GenericValue.h"
30 #include "llvm/ExecutionEngine/JITEventListener.h"
31 #include "llvm/ExecutionEngine/JITMemoryManager.h"
32 #include "llvm/CodeGen/MachineCodeInfo.h"
33 #include "llvm/Target/TargetData.h"
34 #include "llvm/Target/TargetJITInfo.h"
35 #include "llvm/Target/TargetMachine.h"
36 #include "llvm/Target/TargetOptions.h"
37 #include "llvm/Support/Debug.h"
38 #include "llvm/Support/ErrorHandling.h"
39 #include "llvm/Support/MutexGuard.h"
40 #include "llvm/Support/ValueHandle.h"
41 #include "llvm/Support/raw_ostream.h"
42 #include "llvm/System/Disassembler.h"
43 #include "llvm/System/Memory.h"
44 #include "llvm/Target/TargetInstrInfo.h"
45 #include "llvm/ADT/DenseMap.h"
46 #include "llvm/ADT/SmallPtrSet.h"
47 #include "llvm/ADT/SmallVector.h"
48 #include "llvm/ADT/Statistic.h"
49 #include "llvm/ADT/ValueMap.h"
56 STATISTIC(NumBytes, "Number of bytes of machine code compiled");
57 STATISTIC(NumRelos, "Number of relocations applied");
58 STATISTIC(NumRetries, "Number of retries with more memory");
59 static JIT *TheJIT = 0;
62 //===----------------------------------------------------------------------===//
63 // JIT lazy compilation code.
67 class JITResolverState;
69 template<typename ValueTy>
70 struct NoRAUWValueMapConfig : public ValueMapConfig<ValueTy> {
71 typedef JITResolverState *ExtraData;
72 static void onRAUW(JITResolverState *, Value *Old, Value *New) {
73 assert(false && "The JIT doesn't know how to handle a"
74 " RAUW on a value it has emitted.");
78 struct CallSiteValueMapConfig : public NoRAUWValueMapConfig<Function*> {
79 typedef JITResolverState *ExtraData;
80 static void onDelete(JITResolverState *JRS, Function *F);
83 class JITResolverState {
85 typedef ValueMap<Function*, void*, NoRAUWValueMapConfig<Function*> >
86 FunctionToLazyStubMapTy;
87 typedef std::map<void*, AssertingVH<Function> > CallSiteToFunctionMapTy;
88 typedef ValueMap<Function *, SmallPtrSet<void*, 1>,
89 CallSiteValueMapConfig> FunctionToCallSitesMapTy;
90 typedef std::map<AssertingVH<GlobalValue>, void*> GlobalToIndirectSymMapTy;
92 /// FunctionToLazyStubMap - Keep track of the lazy stub created for a
93 /// particular function so that we can reuse them if necessary.
94 FunctionToLazyStubMapTy FunctionToLazyStubMap;
96 /// CallSiteToFunctionMap - Keep track of the function that each lazy call
97 /// site corresponds to, and vice versa.
98 CallSiteToFunctionMapTy CallSiteToFunctionMap;
99 FunctionToCallSitesMapTy FunctionToCallSitesMap;
101 /// GlobalToIndirectSymMap - Keep track of the indirect symbol created for a
102 /// particular GlobalVariable so that we can reuse them if necessary.
103 GlobalToIndirectSymMapTy GlobalToIndirectSymMap;
106 JITResolverState() : FunctionToLazyStubMap(this),
107 FunctionToCallSitesMap(this) {}
109 FunctionToLazyStubMapTy& getFunctionToLazyStubMap(
110 const MutexGuard& locked) {
111 assert(locked.holds(TheJIT->lock));
112 return FunctionToLazyStubMap;
115 GlobalToIndirectSymMapTy& getGlobalToIndirectSymMap(const MutexGuard& locked) {
116 assert(locked.holds(TheJIT->lock));
117 return GlobalToIndirectSymMap;
120 pair<void *, Function *> LookupFunctionFromCallSite(
121 const MutexGuard &locked, void *CallSite) const {
122 assert(locked.holds(TheJIT->lock));
124 // The address given to us for the stub may not be exactly right, it might be
125 // a little bit after the stub. As such, use upper_bound to find it.
126 CallSiteToFunctionMapTy::const_iterator I =
127 CallSiteToFunctionMap.upper_bound(CallSite);
128 assert(I != CallSiteToFunctionMap.begin() &&
129 "This is not a known call site!");
134 void AddCallSite(const MutexGuard &locked, void *CallSite, Function *F) {
135 assert(locked.holds(TheJIT->lock));
137 bool Inserted = CallSiteToFunctionMap.insert(
138 std::make_pair(CallSite, F)).second;
140 assert(Inserted && "Pair was already in CallSiteToFunctionMap");
141 FunctionToCallSitesMap[F].insert(CallSite);
144 // Returns the Function of the stub if a stub was erased, or NULL if there
145 // was no stub. This function uses the call-site->function map to find a
146 // relevant function, but asserts that only stubs and not other call sites
147 // will be passed in.
148 Function *EraseStub(const MutexGuard &locked, void *Stub) {
149 CallSiteToFunctionMapTy::iterator C2F_I =
150 CallSiteToFunctionMap.find(Stub);
151 if (C2F_I == CallSiteToFunctionMap.end()) {
156 Function *const F = C2F_I->second;
158 void *RealStub = FunctionToLazyStubMap.lookup(F);
159 assert(RealStub == Stub &&
160 "Call-site that wasn't a stub pass in to EraseStub");
162 FunctionToLazyStubMap.erase(F);
163 CallSiteToFunctionMap.erase(C2F_I);
165 // Remove the stub from the function->call-sites map, and remove the whole
166 // entry from the map if that was the last call site.
167 FunctionToCallSitesMapTy::iterator F2C_I = FunctionToCallSitesMap.find(F);
168 assert(F2C_I != FunctionToCallSitesMap.end() &&
169 "FunctionToCallSitesMap broken");
170 bool Erased = F2C_I->second.erase(Stub);
172 assert(Erased && "FunctionToCallSitesMap broken");
173 if (F2C_I->second.empty())
174 FunctionToCallSitesMap.erase(F2C_I);
179 void EraseAllCallSites(const MutexGuard &locked, Function *F) {
180 assert(locked.holds(TheJIT->lock));
181 EraseAllCallSitesPrelocked(F);
183 void EraseAllCallSitesPrelocked(Function *F) {
184 FunctionToCallSitesMapTy::iterator F2C = FunctionToCallSitesMap.find(F);
185 if (F2C == FunctionToCallSitesMap.end())
187 for (SmallPtrSet<void*, 1>::const_iterator I = F2C->second.begin(),
188 E = F2C->second.end(); I != E; ++I) {
189 bool Erased = CallSiteToFunctionMap.erase(*I);
191 assert(Erased && "Missing call site->function mapping");
193 FunctionToCallSitesMap.erase(F2C);
197 /// JITResolver - Keep track of, and resolve, call sites for functions that
198 /// have not yet been compiled.
200 typedef JITResolverState::FunctionToLazyStubMapTy FunctionToLazyStubMapTy;
201 typedef JITResolverState::CallSiteToFunctionMapTy CallSiteToFunctionMapTy;
202 typedef JITResolverState::GlobalToIndirectSymMapTy GlobalToIndirectSymMapTy;
204 /// LazyResolverFn - The target lazy resolver function that we actually
205 /// rewrite instructions to use.
206 TargetJITInfo::LazyResolverFn LazyResolverFn;
208 JITResolverState state;
210 /// ExternalFnToStubMap - This is the equivalent of FunctionToLazyStubMap
211 /// for external functions. TODO: Of course, external functions don't need
212 /// a lazy stub. It's actually here to make it more likely that far calls
213 /// succeed, but no single stub can guarantee that. I'll remove this in a
214 /// subsequent checkin when I actually fix far calls.
215 std::map<void*, void*> ExternalFnToStubMap;
217 /// revGOTMap - map addresses to indexes in the GOT
218 std::map<void*, unsigned> revGOTMap;
219 unsigned nextGOTIndex;
223 static JITResolver *TheJITResolver;
225 explicit JITResolver(JIT &jit, JITEmitter &je) : nextGOTIndex(0), JE(je) {
228 LazyResolverFn = jit.getJITInfo().getLazyResolverFunction(JITCompilerFn);
229 assert(TheJITResolver == 0 && "Multiple JIT resolvers?");
230 TheJITResolver = this;
237 /// getLazyFunctionStubIfAvailable - This returns a pointer to a function's
238 /// lazy-compilation stub if it has already been created.
239 void *getLazyFunctionStubIfAvailable(Function *F);
241 /// getLazyFunctionStub - This returns a pointer to a function's
242 /// lazy-compilation stub, creating one on demand as needed.
243 void *getLazyFunctionStub(Function *F);
245 /// getExternalFunctionStub - Return a stub for the function at the
246 /// specified address, created lazily on demand.
247 void *getExternalFunctionStub(void *FnAddr);
249 /// getGlobalValueIndirectSym - Return an indirect symbol containing the
250 /// specified GV address.
251 void *getGlobalValueIndirectSym(GlobalValue *V, void *GVAddress);
253 void getRelocatableGVs(SmallVectorImpl<GlobalValue*> &GVs,
254 SmallVectorImpl<void*> &Ptrs);
256 GlobalValue *invalidateStub(void *Stub);
258 /// getGOTIndexForAddress - Return a new or existing index in the GOT for
259 /// an address. This function only manages slots, it does not manage the
260 /// contents of the slots or the memory associated with the GOT.
261 unsigned getGOTIndexForAddr(void *addr);
263 /// JITCompilerFn - This function is called to resolve a stub to a compiled
264 /// address. If the LLVM Function corresponding to the stub has not yet
265 /// been compiled, this function compiles it first.
266 static void *JITCompilerFn(void *Stub);
269 /// JITEmitter - The JIT implementation of the MachineCodeEmitter, which is
270 /// used to output functions to memory for execution.
271 class JITEmitter : public JITCodeEmitter {
272 JITMemoryManager *MemMgr;
274 // When reattempting to JIT a function after running out of space, we store
275 // the estimated size of the function we're trying to JIT here, so we can
276 // ask the memory manager for at least this much space. When we
277 // successfully emit the function, we reset this back to zero.
278 uintptr_t SizeEstimate;
280 /// Relocations - These are the relocations that the function needs, as
282 std::vector<MachineRelocation> Relocations;
284 /// MBBLocations - This vector is a mapping from MBB ID's to their address.
285 /// It is filled in by the StartMachineBasicBlock callback and queried by
286 /// the getMachineBasicBlockAddress callback.
287 std::vector<uintptr_t> MBBLocations;
289 /// ConstantPool - The constant pool for the current function.
291 MachineConstantPool *ConstantPool;
293 /// ConstantPoolBase - A pointer to the first entry in the constant pool.
295 void *ConstantPoolBase;
297 /// ConstPoolAddresses - Addresses of individual constant pool entries.
299 SmallVector<uintptr_t, 8> ConstPoolAddresses;
301 /// JumpTable - The jump tables for the current function.
303 MachineJumpTableInfo *JumpTable;
305 /// JumpTableBase - A pointer to the first entry in the jump table.
309 /// Resolver - This contains info about the currently resolved functions.
310 JITResolver Resolver;
312 /// DE - The dwarf emitter for the jit.
313 OwningPtr<JITDwarfEmitter> DE;
315 /// DR - The debug registerer for the jit.
316 OwningPtr<JITDebugRegisterer> DR;
318 /// LabelLocations - This vector is a mapping from Label ID's to their
320 std::vector<uintptr_t> LabelLocations;
322 /// MMI - Machine module info for exception informations
323 MachineModuleInfo* MMI;
325 // GVSet - a set to keep track of which globals have been seen
326 SmallPtrSet<const GlobalVariable*, 8> GVSet;
328 // CurFn - The llvm function being emitted. Only valid during
330 const Function *CurFn;
332 /// Information about emitted code, which is passed to the
333 /// JITEventListeners. This is reset in startFunction and used in
335 JITEvent_EmittedFunctionDetails EmissionDetails;
338 void *FunctionBody; // Beginning of the function's allocation.
339 void *Code; // The address the function's code actually starts at.
340 void *ExceptionTable;
341 EmittedCode() : FunctionBody(0), Code(0), ExceptionTable(0) {}
343 struct EmittedFunctionConfig : public ValueMapConfig<const Function*> {
344 typedef JITEmitter *ExtraData;
345 static void onDelete(JITEmitter *, const Function*);
346 static void onRAUW(JITEmitter *, const Function*, const Function*);
348 ValueMap<const Function *, EmittedCode,
349 EmittedFunctionConfig> EmittedFunctions;
351 // CurFnStubUses - For a given Function, a vector of stubs that it
352 // references. This facilitates the JIT detecting that a stub is no
353 // longer used, so that it may be deallocated.
354 DenseMap<AssertingVH<const Function>, SmallVector<void*, 1> > CurFnStubUses;
356 // StubFnRefs - For a given pointer to a stub, a set of Functions which
357 // reference the stub. When the count of a stub's references drops to zero,
358 // the stub is unused.
359 DenseMap<void *, SmallPtrSet<const Function*, 1> > StubFnRefs;
361 DebugLocTuple PrevDLT;
364 JITEmitter(JIT &jit, JITMemoryManager *JMM, TargetMachine &TM)
365 : SizeEstimate(0), Resolver(jit, *this), MMI(0), CurFn(0),
366 EmittedFunctions(this) {
367 MemMgr = JMM ? JMM : JITMemoryManager::CreateDefaultMemManager();
368 if (jit.getJITInfo().needsGOT()) {
369 MemMgr->AllocateGOT();
370 DEBUG(errs() << "JIT is managing a GOT\n");
373 if (DwarfExceptionHandling || JITEmitDebugInfo) {
374 DE.reset(new JITDwarfEmitter(jit));
376 if (JITEmitDebugInfo) {
377 DR.reset(new JITDebugRegisterer(TM));
384 /// classof - Methods for support type inquiry through isa, cast, and
387 static inline bool classof(const JITEmitter*) { return true; }
388 static inline bool classof(const MachineCodeEmitter*) { return true; }
390 JITResolver &getJITResolver() { return Resolver; }
392 virtual void startFunction(MachineFunction &F);
393 virtual bool finishFunction(MachineFunction &F);
395 void emitConstantPool(MachineConstantPool *MCP);
396 void initJumpTableInfo(MachineJumpTableInfo *MJTI);
397 void emitJumpTableInfo(MachineJumpTableInfo *MJTI);
399 virtual void startGVStub(BufferState &BS, const GlobalValue* GV,
400 unsigned StubSize, unsigned Alignment = 1);
401 virtual void startGVStub(BufferState &BS, void *Buffer,
403 virtual void* finishGVStub(BufferState &BS);
405 /// allocateSpace - Reserves space in the current block if any, or
406 /// allocate a new one of the given size.
407 virtual void *allocateSpace(uintptr_t Size, unsigned Alignment);
409 /// allocateGlobal - Allocate memory for a global. Unlike allocateSpace,
410 /// this method does not allocate memory in the current output buffer,
411 /// because a global may live longer than the current function.
412 virtual void *allocateGlobal(uintptr_t Size, unsigned Alignment);
414 virtual void addRelocation(const MachineRelocation &MR) {
415 Relocations.push_back(MR);
418 virtual void StartMachineBasicBlock(MachineBasicBlock *MBB) {
419 if (MBBLocations.size() <= (unsigned)MBB->getNumber())
420 MBBLocations.resize((MBB->getNumber()+1)*2);
421 MBBLocations[MBB->getNumber()] = getCurrentPCValue();
422 DEBUG(errs() << "JIT: Emitting BB" << MBB->getNumber() << " at ["
423 << (void*) getCurrentPCValue() << "]\n");
426 virtual uintptr_t getConstantPoolEntryAddress(unsigned Entry) const;
427 virtual uintptr_t getJumpTableEntryAddress(unsigned Entry) const;
429 virtual uintptr_t getMachineBasicBlockAddress(MachineBasicBlock *MBB) const {
430 assert(MBBLocations.size() > (unsigned)MBB->getNumber() &&
431 MBBLocations[MBB->getNumber()] && "MBB not emitted!");
432 return MBBLocations[MBB->getNumber()];
435 /// retryWithMoreMemory - Log a retry and deallocate all memory for the
436 /// given function. Increase the minimum allocation size so that we get
437 /// more memory next time.
438 void retryWithMoreMemory(MachineFunction &F);
440 /// deallocateMemForFunction - Deallocate all memory for the specified
442 void deallocateMemForFunction(const Function *F);
444 /// AddStubToCurrentFunction - Mark the current function being JIT'd as
445 /// using the stub at the specified address. Allows
446 /// deallocateMemForFunction to also remove stubs no longer referenced.
447 void AddStubToCurrentFunction(void *Stub);
449 virtual void processDebugLoc(DebugLoc DL, bool BeforePrintingInsn);
451 virtual void emitLabel(uint64_t LabelID) {
452 if (LabelLocations.size() <= LabelID)
453 LabelLocations.resize((LabelID+1)*2);
454 LabelLocations[LabelID] = getCurrentPCValue();
457 virtual uintptr_t getLabelAddress(uint64_t LabelID) const {
458 assert(LabelLocations.size() > (unsigned)LabelID &&
459 LabelLocations[LabelID] && "Label not emitted!");
460 return LabelLocations[LabelID];
463 virtual void setModuleInfo(MachineModuleInfo* Info) {
465 if (DE.get()) DE->setModuleInfo(Info);
468 void setMemoryExecutable() {
469 MemMgr->setMemoryExecutable();
472 JITMemoryManager *getMemMgr() const { return MemMgr; }
475 void *getPointerToGlobal(GlobalValue *GV, void *Reference,
476 bool MayNeedFarStub);
477 void *getPointerToGVIndirectSym(GlobalValue *V, void *Reference);
478 unsigned addSizeOfGlobal(const GlobalVariable *GV, unsigned Size);
479 unsigned addSizeOfGlobalsInConstantVal(const Constant *C, unsigned Size);
480 unsigned addSizeOfGlobalsInInitializer(const Constant *Init, unsigned Size);
481 unsigned GetSizeOfGlobalsInBytes(MachineFunction &MF);
485 JITResolver *JITResolver::TheJITResolver = 0;
487 void CallSiteValueMapConfig::onDelete(JITResolverState *JRS, Function *F) {
488 JRS->EraseAllCallSitesPrelocked(F);
491 /// getLazyFunctionStubIfAvailable - This returns a pointer to a function stub
492 /// if it has already been created.
493 void *JITResolver::getLazyFunctionStubIfAvailable(Function *F) {
494 MutexGuard locked(TheJIT->lock);
496 // If we already have a stub for this function, recycle it.
497 return state.getFunctionToLazyStubMap(locked).lookup(F);
500 /// getFunctionStub - This returns a pointer to a function stub, creating
501 /// one on demand as needed.
502 void *JITResolver::getLazyFunctionStub(Function *F) {
503 MutexGuard locked(TheJIT->lock);
505 // If we already have a lazy stub for this function, recycle it.
506 void *&Stub = state.getFunctionToLazyStubMap(locked)[F];
507 if (Stub) return Stub;
509 // Call the lazy resolver function if we are JIT'ing lazily. Otherwise we
510 // must resolve the symbol now.
511 void *Actual = TheJIT->isCompilingLazily()
512 ? (void *)(intptr_t)LazyResolverFn : (void *)0;
514 // If this is an external declaration, attempt to resolve the address now
515 // to place in the stub.
516 if (F->isDeclaration() && !F->hasNotBeenReadFromBitcode()) {
517 Actual = TheJIT->getPointerToFunction(F);
519 // If we resolved the symbol to a null address (eg. a weak external)
520 // don't emit a stub. Return a null pointer to the application.
521 if (!Actual) return 0;
524 MachineCodeEmitter::BufferState BS;
525 TargetJITInfo::StubLayout SL = TheJIT->getJITInfo().getStubLayout();
526 JE.startGVStub(BS, F, SL.Size, SL.Alignment);
527 // Codegen a new stub, calling the lazy resolver or the actual address of the
528 // external function, if it was resolved.
529 Stub = TheJIT->getJITInfo().emitFunctionStub(F, Actual, JE);
532 if (Actual != (void*)(intptr_t)LazyResolverFn) {
533 // If we are getting the stub for an external function, we really want the
534 // address of the stub in the GlobalAddressMap for the JIT, not the address
535 // of the external function.
536 TheJIT->updateGlobalMapping(F, Stub);
539 DEBUG(errs() << "JIT: Lazy stub emitted at [" << Stub << "] for function '"
540 << F->getName() << "'\n");
542 // Finally, keep track of the stub-to-Function mapping so that the
543 // JITCompilerFn knows which function to compile!
544 state.AddCallSite(locked, Stub, F);
546 // If we are JIT'ing non-lazily but need to call a function that does not
547 // exist yet, add it to the JIT's work list so that we can fill in the stub
549 if (!Actual && !TheJIT->isCompilingLazily())
550 if (!F->isDeclaration() || F->hasNotBeenReadFromBitcode())
551 TheJIT->addPendingFunction(F);
556 /// getGlobalValueIndirectSym - Return a lazy pointer containing the specified
558 void *JITResolver::getGlobalValueIndirectSym(GlobalValue *GV, void *GVAddress) {
559 MutexGuard locked(TheJIT->lock);
561 // If we already have a stub for this global variable, recycle it.
562 void *&IndirectSym = state.getGlobalToIndirectSymMap(locked)[GV];
563 if (IndirectSym) return IndirectSym;
565 // Otherwise, codegen a new indirect symbol.
566 IndirectSym = TheJIT->getJITInfo().emitGlobalValueIndirectSym(GV, GVAddress,
569 DEBUG(errs() << "JIT: Indirect symbol emitted at [" << IndirectSym
570 << "] for GV '" << GV->getName() << "'\n");
575 /// getExternalFunctionStub - Return a stub for the function at the
576 /// specified address, created lazily on demand.
577 void *JITResolver::getExternalFunctionStub(void *FnAddr) {
578 // If we already have a stub for this function, recycle it.
579 void *&Stub = ExternalFnToStubMap[FnAddr];
580 if (Stub) return Stub;
582 MachineCodeEmitter::BufferState BS;
583 TargetJITInfo::StubLayout SL = TheJIT->getJITInfo().getStubLayout();
584 JE.startGVStub(BS, 0, SL.Size, SL.Alignment);
585 Stub = TheJIT->getJITInfo().emitFunctionStub(0, FnAddr, JE);
588 DEBUG(errs() << "JIT: Stub emitted at [" << Stub
589 << "] for external function at '" << FnAddr << "'\n");
593 unsigned JITResolver::getGOTIndexForAddr(void* addr) {
594 unsigned idx = revGOTMap[addr];
596 idx = ++nextGOTIndex;
597 revGOTMap[addr] = idx;
598 DEBUG(errs() << "JIT: Adding GOT entry " << idx << " for addr ["
604 void JITResolver::getRelocatableGVs(SmallVectorImpl<GlobalValue*> &GVs,
605 SmallVectorImpl<void*> &Ptrs) {
606 MutexGuard locked(TheJIT->lock);
608 const FunctionToLazyStubMapTy &FM = state.getFunctionToLazyStubMap(locked);
609 GlobalToIndirectSymMapTy &GM = state.getGlobalToIndirectSymMap(locked);
611 for (FunctionToLazyStubMapTy::const_iterator i = FM.begin(), e = FM.end();
613 Function *F = i->first;
614 if (F->isDeclaration() && F->hasExternalLinkage()) {
615 GVs.push_back(i->first);
616 Ptrs.push_back(i->second);
619 for (GlobalToIndirectSymMapTy::iterator i = GM.begin(), e = GM.end();
621 GVs.push_back(i->first);
622 Ptrs.push_back(i->second);
626 GlobalValue *JITResolver::invalidateStub(void *Stub) {
627 MutexGuard locked(TheJIT->lock);
629 GlobalToIndirectSymMapTy &GM = state.getGlobalToIndirectSymMap(locked);
631 // Look up the cheap way first, to see if it's a function stub we are
632 // invalidating. If so, remove it from both the forward and reverse maps.
633 if (Function *F = state.EraseStub(locked, Stub)) {
637 // Otherwise, it might be an indirect symbol stub. Find it and remove it.
638 for (GlobalToIndirectSymMapTy::iterator i = GM.begin(), e = GM.end();
640 if (i->second != Stub)
642 GlobalValue *GV = i->first;
647 // Lastly, check to see if it's in the ExternalFnToStubMap.
648 for (std::map<void *, void *>::iterator i = ExternalFnToStubMap.begin(),
649 e = ExternalFnToStubMap.end(); i != e; ++i) {
650 if (i->second != Stub)
652 ExternalFnToStubMap.erase(i);
659 /// JITCompilerFn - This function is called when a lazy compilation stub has
660 /// been entered. It looks up which function this stub corresponds to, compiles
661 /// it if necessary, then returns the resultant function pointer.
662 void *JITResolver::JITCompilerFn(void *Stub) {
663 JITResolver &JR = *TheJITResolver;
669 // Only lock for getting the Function. The call getPointerToFunction made
670 // in this function might trigger function materializing, which requires
671 // JIT lock to be unlocked.
672 MutexGuard locked(TheJIT->lock);
674 // The address given to us for the stub may not be exactly right, it might
675 // be a little bit after the stub. As such, use upper_bound to find it.
676 pair<void*, Function*> I =
677 JR.state.LookupFunctionFromCallSite(locked, Stub);
682 // If we have already code generated the function, just return the address.
683 void *Result = TheJIT->getPointerToGlobalIfAvailable(F);
686 // Otherwise we don't have it, do lazy compilation now.
688 // If lazy compilation is disabled, emit a useful error message and abort.
689 if (!TheJIT->isCompilingLazily()) {
690 llvm_report_error("LLVM JIT requested to do lazy compilation of function '"
691 + F->getName() + "' when lazy compiles are disabled!");
694 DEBUG(errs() << "JIT: Lazily resolving function '" << F->getName()
695 << "' In stub ptr = " << Stub << " actual ptr = "
696 << ActualPtr << "\n");
698 Result = TheJIT->getPointerToFunction(F);
701 // Reacquire the lock to update the GOT map.
702 MutexGuard locked(TheJIT->lock);
704 // We might like to remove the call site from the CallSiteToFunction map, but
705 // we can't do that! Multiple threads could be stuck, waiting to acquire the
706 // lock above. As soon as the 1st function finishes compiling the function,
707 // the next one will be released, and needs to be able to find the function it
710 // FIXME: We could rewrite all references to this stub if we knew them.
712 // What we will do is set the compiled function address to map to the
713 // same GOT entry as the stub so that later clients may update the GOT
714 // if they see it still using the stub address.
715 // Note: this is done so the Resolver doesn't have to manage GOT memory
716 // Do this without allocating map space if the target isn't using a GOT
717 if(JR.revGOTMap.find(Stub) != JR.revGOTMap.end())
718 JR.revGOTMap[Result] = JR.revGOTMap[Stub];
723 //===----------------------------------------------------------------------===//
726 void *JITEmitter::getPointerToGlobal(GlobalValue *V, void *Reference,
727 bool MayNeedFarStub) {
728 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V))
729 return TheJIT->getOrEmitGlobalVariable(GV);
731 if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V))
732 return TheJIT->getPointerToGlobal(GA->resolveAliasedGlobal(false));
734 // If we have already compiled the function, return a pointer to its body.
735 Function *F = cast<Function>(V);
737 void *FnStub = Resolver.getLazyFunctionStubIfAvailable(F);
739 // Return the function stub if it's already created. We do this first so
740 // that we're returning the same address for the function as any previous
741 // call. TODO: Yes, this is wrong. The lazy stub isn't guaranteed to be
742 // close enough to call.
743 AddStubToCurrentFunction(FnStub);
747 // If we know the target can handle arbitrary-distance calls, try to
748 // return a direct pointer.
749 if (!MayNeedFarStub) {
750 // If we have code, go ahead and return that.
751 void *ResultPtr = TheJIT->getPointerToGlobalIfAvailable(F);
752 if (ResultPtr) return ResultPtr;
754 // If this is an external function pointer, we can force the JIT to
755 // 'compile' it, which really just adds it to the map.
756 if (F->isDeclaration() && !F->hasNotBeenReadFromBitcode())
757 return TheJIT->getPointerToFunction(F);
760 // Otherwise, we may need a to emit a stub, and, conservatively, we
762 void *StubAddr = Resolver.getLazyFunctionStub(F);
764 // Add the stub to the current function's list of referenced stubs, so we can
765 // deallocate them if the current function is ever freed. It's possible to
766 // return null from getLazyFunctionStub in the case of a weak extern that
769 AddStubToCurrentFunction(StubAddr);
774 void *JITEmitter::getPointerToGVIndirectSym(GlobalValue *V, void *Reference) {
775 // Make sure GV is emitted first, and create a stub containing the fully
777 void *GVAddress = getPointerToGlobal(V, Reference, false);
778 void *StubAddr = Resolver.getGlobalValueIndirectSym(V, GVAddress);
780 // Add the stub to the current function's list of referenced stubs, so we can
781 // deallocate them if the current function is ever freed.
782 AddStubToCurrentFunction(StubAddr);
787 void JITEmitter::AddStubToCurrentFunction(void *StubAddr) {
788 assert(CurFn && "Stub added to current function, but current function is 0!");
790 SmallVectorImpl<void*> &StubsUsed = CurFnStubUses[CurFn];
791 StubsUsed.push_back(StubAddr);
793 SmallPtrSet<const Function *, 1> &FnRefs = StubFnRefs[StubAddr];
794 FnRefs.insert(CurFn);
797 void JITEmitter::processDebugLoc(DebugLoc DL, bool BeforePrintingInsn) {
798 if (!DL.isUnknown()) {
799 DebugLocTuple CurDLT = EmissionDetails.MF->getDebugLocTuple(DL);
801 if (BeforePrintingInsn) {
802 if (CurDLT.Scope != 0 && PrevDLT != CurDLT) {
803 JITEvent_EmittedFunctionDetails::LineStart NextLine;
804 NextLine.Address = getCurrentPCValue();
806 EmissionDetails.LineStarts.push_back(NextLine);
814 static unsigned GetConstantPoolSizeInBytes(MachineConstantPool *MCP,
815 const TargetData *TD) {
816 const std::vector<MachineConstantPoolEntry> &Constants = MCP->getConstants();
817 if (Constants.empty()) return 0;
820 for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
821 MachineConstantPoolEntry CPE = Constants[i];
822 unsigned AlignMask = CPE.getAlignment() - 1;
823 Size = (Size + AlignMask) & ~AlignMask;
824 const Type *Ty = CPE.getType();
825 Size += TD->getTypeAllocSize(Ty);
830 static unsigned GetJumpTableSizeInBytes(MachineJumpTableInfo *MJTI) {
831 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
832 if (JT.empty()) return 0;
834 unsigned NumEntries = 0;
835 for (unsigned i = 0, e = JT.size(); i != e; ++i)
836 NumEntries += JT[i].MBBs.size();
838 unsigned EntrySize = MJTI->getEntrySize();
840 return NumEntries * EntrySize;
843 static uintptr_t RoundUpToAlign(uintptr_t Size, unsigned Alignment) {
844 if (Alignment == 0) Alignment = 1;
845 // Since we do not know where the buffer will be allocated, be pessimistic.
846 return Size + Alignment;
849 /// addSizeOfGlobal - add the size of the global (plus any alignment padding)
850 /// into the running total Size.
852 unsigned JITEmitter::addSizeOfGlobal(const GlobalVariable *GV, unsigned Size) {
853 const Type *ElTy = GV->getType()->getElementType();
854 size_t GVSize = (size_t)TheJIT->getTargetData()->getTypeAllocSize(ElTy);
856 (size_t)TheJIT->getTargetData()->getPreferredAlignment(GV);
857 DEBUG(errs() << "JIT: Adding in size " << GVSize << " alignment " << GVAlign);
859 // Assume code section ends with worst possible alignment, so first
860 // variable needs maximal padding.
863 Size = ((Size+GVAlign-1)/GVAlign)*GVAlign;
868 /// addSizeOfGlobalsInConstantVal - find any globals that we haven't seen yet
869 /// but are referenced from the constant; put them in GVSet and add their
870 /// size into the running total Size.
872 unsigned JITEmitter::addSizeOfGlobalsInConstantVal(const Constant *C,
874 // If its undefined, return the garbage.
875 if (isa<UndefValue>(C))
878 // If the value is a ConstantExpr
879 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
880 Constant *Op0 = CE->getOperand(0);
881 switch (CE->getOpcode()) {
882 case Instruction::GetElementPtr:
883 case Instruction::Trunc:
884 case Instruction::ZExt:
885 case Instruction::SExt:
886 case Instruction::FPTrunc:
887 case Instruction::FPExt:
888 case Instruction::UIToFP:
889 case Instruction::SIToFP:
890 case Instruction::FPToUI:
891 case Instruction::FPToSI:
892 case Instruction::PtrToInt:
893 case Instruction::IntToPtr:
894 case Instruction::BitCast: {
895 Size = addSizeOfGlobalsInConstantVal(Op0, Size);
898 case Instruction::Add:
899 case Instruction::FAdd:
900 case Instruction::Sub:
901 case Instruction::FSub:
902 case Instruction::Mul:
903 case Instruction::FMul:
904 case Instruction::UDiv:
905 case Instruction::SDiv:
906 case Instruction::URem:
907 case Instruction::SRem:
908 case Instruction::And:
909 case Instruction::Or:
910 case Instruction::Xor: {
911 Size = addSizeOfGlobalsInConstantVal(Op0, Size);
912 Size = addSizeOfGlobalsInConstantVal(CE->getOperand(1), Size);
917 raw_string_ostream Msg(msg);
918 Msg << "ConstantExpr not handled: " << *CE;
919 llvm_report_error(Msg.str());
924 if (C->getType()->getTypeID() == Type::PointerTyID)
925 if (const GlobalVariable* GV = dyn_cast<GlobalVariable>(C))
926 if (GVSet.insert(GV))
927 Size = addSizeOfGlobal(GV, Size);
932 /// addSizeOfGLobalsInInitializer - handle any globals that we haven't seen yet
933 /// but are referenced from the given initializer.
935 unsigned JITEmitter::addSizeOfGlobalsInInitializer(const Constant *Init,
937 if (!isa<UndefValue>(Init) &&
938 !isa<ConstantVector>(Init) &&
939 !isa<ConstantAggregateZero>(Init) &&
940 !isa<ConstantArray>(Init) &&
941 !isa<ConstantStruct>(Init) &&
942 Init->getType()->isFirstClassType())
943 Size = addSizeOfGlobalsInConstantVal(Init, Size);
947 /// GetSizeOfGlobalsInBytes - walk the code for the function, looking for
948 /// globals; then walk the initializers of those globals looking for more.
949 /// If their size has not been considered yet, add it into the running total
952 unsigned JITEmitter::GetSizeOfGlobalsInBytes(MachineFunction &MF) {
956 for (MachineFunction::iterator MBB = MF.begin(), E = MF.end();
958 for (MachineBasicBlock::const_iterator I = MBB->begin(), E = MBB->end();
960 const TargetInstrDesc &Desc = I->getDesc();
961 const MachineInstr &MI = *I;
962 unsigned NumOps = Desc.getNumOperands();
963 for (unsigned CurOp = 0; CurOp < NumOps; CurOp++) {
964 const MachineOperand &MO = MI.getOperand(CurOp);
966 GlobalValue* V = MO.getGlobal();
967 const GlobalVariable *GV = dyn_cast<const GlobalVariable>(V);
970 // If seen in previous function, it will have an entry here.
971 if (TheJIT->getPointerToGlobalIfAvailable(GV))
973 // If seen earlier in this function, it will have an entry here.
974 // FIXME: it should be possible to combine these tables, by
975 // assuming the addresses of the new globals in this module
976 // start at 0 (or something) and adjusting them after codegen
977 // complete. Another possibility is to grab a marker bit in GV.
978 if (GVSet.insert(GV))
979 // A variable as yet unseen. Add in its size.
980 Size = addSizeOfGlobal(GV, Size);
985 DEBUG(errs() << "JIT: About to look through initializers\n");
986 // Look for more globals that are referenced only from initializers.
987 // GVSet.end is computed each time because the set can grow as we go.
988 for (SmallPtrSet<const GlobalVariable *, 8>::iterator I = GVSet.begin();
989 I != GVSet.end(); I++) {
990 const GlobalVariable* GV = *I;
991 if (GV->hasInitializer())
992 Size = addSizeOfGlobalsInInitializer(GV->getInitializer(), Size);
998 void JITEmitter::startFunction(MachineFunction &F) {
999 DEBUG(errs() << "JIT: Starting CodeGen of Function "
1000 << F.getFunction()->getName() << "\n");
1002 uintptr_t ActualSize = 0;
1003 // Set the memory writable, if it's not already
1004 MemMgr->setMemoryWritable();
1005 if (MemMgr->NeedsExactSize()) {
1006 DEBUG(errs() << "JIT: ExactSize\n");
1007 const TargetInstrInfo* TII = F.getTarget().getInstrInfo();
1008 MachineJumpTableInfo *MJTI = F.getJumpTableInfo();
1009 MachineConstantPool *MCP = F.getConstantPool();
1011 // Ensure the constant pool/jump table info is at least 4-byte aligned.
1012 ActualSize = RoundUpToAlign(ActualSize, 16);
1014 // Add the alignment of the constant pool
1015 ActualSize = RoundUpToAlign(ActualSize, MCP->getConstantPoolAlignment());
1017 // Add the constant pool size
1018 ActualSize += GetConstantPoolSizeInBytes(MCP, TheJIT->getTargetData());
1020 // Add the aligment of the jump table info
1021 ActualSize = RoundUpToAlign(ActualSize, MJTI->getAlignment());
1023 // Add the jump table size
1024 ActualSize += GetJumpTableSizeInBytes(MJTI);
1026 // Add the alignment for the function
1027 ActualSize = RoundUpToAlign(ActualSize,
1028 std::max(F.getFunction()->getAlignment(), 8U));
1030 // Add the function size
1031 ActualSize += TII->GetFunctionSizeInBytes(F);
1033 DEBUG(errs() << "JIT: ActualSize before globals " << ActualSize << "\n");
1034 // Add the size of the globals that will be allocated after this function.
1035 // These are all the ones referenced from this function that were not
1036 // previously allocated.
1037 ActualSize += GetSizeOfGlobalsInBytes(F);
1038 DEBUG(errs() << "JIT: ActualSize after globals " << ActualSize << "\n");
1039 } else if (SizeEstimate > 0) {
1040 // SizeEstimate will be non-zero on reallocation attempts.
1041 ActualSize = SizeEstimate;
1044 BufferBegin = CurBufferPtr = MemMgr->startFunctionBody(F.getFunction(),
1046 BufferEnd = BufferBegin+ActualSize;
1047 EmittedFunctions[F.getFunction()].FunctionBody = BufferBegin;
1049 // Ensure the constant pool/jump table info is at least 4-byte aligned.
1052 emitConstantPool(F.getConstantPool());
1053 initJumpTableInfo(F.getJumpTableInfo());
1055 // About to start emitting the machine code for the function.
1056 emitAlignment(std::max(F.getFunction()->getAlignment(), 8U));
1057 TheJIT->updateGlobalMapping(F.getFunction(), CurBufferPtr);
1058 EmittedFunctions[F.getFunction()].Code = CurBufferPtr;
1060 MBBLocations.clear();
1062 EmissionDetails.MF = &F;
1063 EmissionDetails.LineStarts.clear();
1066 bool JITEmitter::finishFunction(MachineFunction &F) {
1067 if (CurBufferPtr == BufferEnd) {
1068 // We must call endFunctionBody before retrying, because
1069 // deallocateMemForFunction requires it.
1070 MemMgr->endFunctionBody(F.getFunction(), BufferBegin, CurBufferPtr);
1071 retryWithMoreMemory(F);
1075 emitJumpTableInfo(F.getJumpTableInfo());
1077 // FnStart is the start of the text, not the start of the constant pool and
1078 // other per-function data.
1080 (uint8_t *)TheJIT->getPointerToGlobalIfAvailable(F.getFunction());
1082 // FnEnd is the end of the function's machine code.
1083 uint8_t *FnEnd = CurBufferPtr;
1085 if (!Relocations.empty()) {
1086 CurFn = F.getFunction();
1087 NumRelos += Relocations.size();
1089 // Resolve the relocations to concrete pointers.
1090 for (unsigned i = 0, e = Relocations.size(); i != e; ++i) {
1091 MachineRelocation &MR = Relocations[i];
1092 void *ResultPtr = 0;
1093 if (!MR.letTargetResolve()) {
1094 if (MR.isExternalSymbol()) {
1095 ResultPtr = TheJIT->getPointerToNamedFunction(MR.getExternalSymbol(),
1097 DEBUG(errs() << "JIT: Map \'" << MR.getExternalSymbol() << "\' to ["
1098 << ResultPtr << "]\n");
1100 // If the target REALLY wants a stub for this function, emit it now.
1101 if (MR.mayNeedFarStub()) {
1102 ResultPtr = Resolver.getExternalFunctionStub(ResultPtr);
1104 } else if (MR.isGlobalValue()) {
1105 ResultPtr = getPointerToGlobal(MR.getGlobalValue(),
1106 BufferBegin+MR.getMachineCodeOffset(),
1107 MR.mayNeedFarStub());
1108 } else if (MR.isIndirectSymbol()) {
1109 ResultPtr = getPointerToGVIndirectSym(
1110 MR.getGlobalValue(), BufferBegin+MR.getMachineCodeOffset());
1111 } else if (MR.isBasicBlock()) {
1112 ResultPtr = (void*)getMachineBasicBlockAddress(MR.getBasicBlock());
1113 } else if (MR.isConstantPoolIndex()) {
1114 ResultPtr = (void*)getConstantPoolEntryAddress(MR.getConstantPoolIndex());
1116 assert(MR.isJumpTableIndex());
1117 ResultPtr=(void*)getJumpTableEntryAddress(MR.getJumpTableIndex());
1120 MR.setResultPointer(ResultPtr);
1123 // if we are managing the GOT and the relocation wants an index,
1125 if (MR.isGOTRelative() && MemMgr->isManagingGOT()) {
1126 unsigned idx = Resolver.getGOTIndexForAddr(ResultPtr);
1127 MR.setGOTIndex(idx);
1128 if (((void**)MemMgr->getGOTBase())[idx] != ResultPtr) {
1129 DEBUG(errs() << "JIT: GOT was out of date for " << ResultPtr
1130 << " pointing at " << ((void**)MemMgr->getGOTBase())[idx]
1132 ((void**)MemMgr->getGOTBase())[idx] = ResultPtr;
1138 TheJIT->getJITInfo().relocate(BufferBegin, &Relocations[0],
1139 Relocations.size(), MemMgr->getGOTBase());
1142 // Update the GOT entry for F to point to the new code.
1143 if (MemMgr->isManagingGOT()) {
1144 unsigned idx = Resolver.getGOTIndexForAddr((void*)BufferBegin);
1145 if (((void**)MemMgr->getGOTBase())[idx] != (void*)BufferBegin) {
1146 DEBUG(errs() << "JIT: GOT was out of date for " << (void*)BufferBegin
1147 << " pointing at " << ((void**)MemMgr->getGOTBase())[idx]
1149 ((void**)MemMgr->getGOTBase())[idx] = (void*)BufferBegin;
1153 // CurBufferPtr may have moved beyond FnEnd, due to memory allocation for
1154 // global variables that were referenced in the relocations.
1155 MemMgr->endFunctionBody(F.getFunction(), BufferBegin, CurBufferPtr);
1157 if (CurBufferPtr == BufferEnd) {
1158 retryWithMoreMemory(F);
1161 // Now that we've succeeded in emitting the function, reset the
1162 // SizeEstimate back down to zero.
1166 BufferBegin = CurBufferPtr = 0;
1167 NumBytes += FnEnd-FnStart;
1169 // Invalidate the icache if necessary.
1170 sys::Memory::InvalidateInstructionCache(FnStart, FnEnd-FnStart);
1172 TheJIT->NotifyFunctionEmitted(*F.getFunction(), FnStart, FnEnd-FnStart,
1175 DEBUG(errs() << "JIT: Finished CodeGen of [" << (void*)FnStart
1176 << "] Function: " << F.getFunction()->getName()
1177 << ": " << (FnEnd-FnStart) << " bytes of text, "
1178 << Relocations.size() << " relocations\n");
1180 Relocations.clear();
1181 ConstPoolAddresses.clear();
1183 // Mark code region readable and executable if it's not so already.
1184 MemMgr->setMemoryExecutable();
1187 if (sys::hasDisassembler()) {
1188 errs() << "JIT: Disassembled code:\n";
1189 errs() << sys::disassembleBuffer(FnStart, FnEnd-FnStart,
1190 (uintptr_t)FnStart);
1192 errs() << "JIT: Binary code:\n";
1193 uint8_t* q = FnStart;
1194 for (int i = 0; q < FnEnd; q += 4, ++i) {
1198 errs() << "JIT: " << (long)(q - FnStart) << ": ";
1200 for (int j = 3; j >= 0; --j) {
1204 errs() << (unsigned short)q[j];
1216 if (DwarfExceptionHandling || JITEmitDebugInfo) {
1217 uintptr_t ActualSize = 0;
1221 if (MemMgr->NeedsExactSize()) {
1222 ActualSize = DE->GetDwarfTableSizeInBytes(F, *this, FnStart, FnEnd);
1225 BufferBegin = CurBufferPtr = MemMgr->startExceptionTable(F.getFunction(),
1227 BufferEnd = BufferBegin+ActualSize;
1228 EmittedFunctions[F.getFunction()].ExceptionTable = BufferBegin;
1230 uint8_t *FrameRegister = DE->EmitDwarfTable(F, *this, FnStart, FnEnd,
1232 MemMgr->endExceptionTable(F.getFunction(), BufferBegin, CurBufferPtr,
1234 uint8_t *EhEnd = CurBufferPtr;
1235 RestoreStateFrom(BS);
1237 if (DwarfExceptionHandling) {
1238 TheJIT->RegisterTable(FrameRegister);
1241 if (JITEmitDebugInfo) {
1243 I.FnStart = FnStart;
1245 I.EhStart = EhStart;
1247 DR->RegisterFunction(F.getFunction(), I);
1257 void JITEmitter::retryWithMoreMemory(MachineFunction &F) {
1258 DEBUG(errs() << "JIT: Ran out of space for native code. Reattempting.\n");
1259 Relocations.clear(); // Clear the old relocations or we'll reapply them.
1260 ConstPoolAddresses.clear();
1262 deallocateMemForFunction(F.getFunction());
1263 // Try again with at least twice as much free space.
1264 SizeEstimate = (uintptr_t)(2 * (BufferEnd - BufferBegin));
1267 /// deallocateMemForFunction - Deallocate all memory for the specified
1268 /// function body. Also drop any references the function has to stubs.
1269 /// May be called while the Function is being destroyed inside ~Value().
1270 void JITEmitter::deallocateMemForFunction(const Function *F) {
1271 ValueMap<const Function *, EmittedCode, EmittedFunctionConfig>::iterator
1272 Emitted = EmittedFunctions.find(F);
1273 if (Emitted != EmittedFunctions.end()) {
1274 MemMgr->deallocateFunctionBody(Emitted->second.FunctionBody);
1275 MemMgr->deallocateExceptionTable(Emitted->second.ExceptionTable);
1276 TheJIT->NotifyFreeingMachineCode(Emitted->second.Code);
1278 EmittedFunctions.erase(Emitted);
1281 // TODO: Do we need to unregister exception handling information from libgcc
1284 if (JITEmitDebugInfo) {
1285 DR->UnregisterFunction(F);
1288 // If the function did not reference any stubs, return.
1289 if (CurFnStubUses.find(F) == CurFnStubUses.end())
1292 // For each referenced stub, erase the reference to this function, and then
1293 // erase the list of referenced stubs.
1294 SmallVectorImpl<void *> &StubList = CurFnStubUses[F];
1295 for (unsigned i = 0, e = StubList.size(); i != e; ++i) {
1296 void *Stub = StubList[i];
1298 // If we already invalidated this stub for this function, continue.
1299 if (StubFnRefs.count(Stub) == 0)
1302 SmallPtrSet<const Function *, 1> &FnRefs = StubFnRefs[Stub];
1305 // If this function was the last reference to the stub, invalidate the stub
1306 // in the JITResolver. Were there a memory manager deallocateStub routine,
1307 // we could call that at this point too.
1308 if (FnRefs.empty()) {
1309 DEBUG(errs() << "\nJIT: Invalidated Stub at [" << Stub << "]\n");
1310 StubFnRefs.erase(Stub);
1312 // Invalidate the stub. If it is a GV stub, update the JIT's global
1313 // mapping for that GV to zero.
1314 GlobalValue *GV = Resolver.invalidateStub(Stub);
1316 TheJIT->updateGlobalMapping(GV, 0);
1320 CurFnStubUses.erase(F);
1324 void* JITEmitter::allocateSpace(uintptr_t Size, unsigned Alignment) {
1326 return JITCodeEmitter::allocateSpace(Size, Alignment);
1328 // create a new memory block if there is no active one.
1329 // care must be taken so that BufferBegin is invalidated when a
1331 BufferBegin = CurBufferPtr = MemMgr->allocateSpace(Size, Alignment);
1332 BufferEnd = BufferBegin+Size;
1333 return CurBufferPtr;
1336 void* JITEmitter::allocateGlobal(uintptr_t Size, unsigned Alignment) {
1337 // Delegate this call through the memory manager.
1338 return MemMgr->allocateGlobal(Size, Alignment);
1341 void JITEmitter::emitConstantPool(MachineConstantPool *MCP) {
1342 if (TheJIT->getJITInfo().hasCustomConstantPool())
1345 const std::vector<MachineConstantPoolEntry> &Constants = MCP->getConstants();
1346 if (Constants.empty()) return;
1348 unsigned Size = GetConstantPoolSizeInBytes(MCP, TheJIT->getTargetData());
1349 unsigned Align = MCP->getConstantPoolAlignment();
1350 ConstantPoolBase = allocateSpace(Size, Align);
1353 if (ConstantPoolBase == 0) return; // Buffer overflow.
1355 DEBUG(errs() << "JIT: Emitted constant pool at [" << ConstantPoolBase
1356 << "] (size: " << Size << ", alignment: " << Align << ")\n");
1358 // Initialize the memory for all of the constant pool entries.
1359 unsigned Offset = 0;
1360 for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
1361 MachineConstantPoolEntry CPE = Constants[i];
1362 unsigned AlignMask = CPE.getAlignment() - 1;
1363 Offset = (Offset + AlignMask) & ~AlignMask;
1365 uintptr_t CAddr = (uintptr_t)ConstantPoolBase + Offset;
1366 ConstPoolAddresses.push_back(CAddr);
1367 if (CPE.isMachineConstantPoolEntry()) {
1368 // FIXME: add support to lower machine constant pool values into bytes!
1369 llvm_report_error("Initialize memory with machine specific constant pool"
1370 "entry has not been implemented!");
1372 TheJIT->InitializeMemory(CPE.Val.ConstVal, (void*)CAddr);
1373 DEBUG(errs() << "JIT: CP" << i << " at [0x";
1374 errs().write_hex(CAddr) << "]\n");
1376 const Type *Ty = CPE.Val.ConstVal->getType();
1377 Offset += TheJIT->getTargetData()->getTypeAllocSize(Ty);
1381 void JITEmitter::initJumpTableInfo(MachineJumpTableInfo *MJTI) {
1382 if (TheJIT->getJITInfo().hasCustomJumpTables())
1385 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1386 if (JT.empty()) return;
1388 unsigned NumEntries = 0;
1389 for (unsigned i = 0, e = JT.size(); i != e; ++i)
1390 NumEntries += JT[i].MBBs.size();
1392 unsigned EntrySize = MJTI->getEntrySize();
1394 // Just allocate space for all the jump tables now. We will fix up the actual
1395 // MBB entries in the tables after we emit the code for each block, since then
1396 // we will know the final locations of the MBBs in memory.
1398 JumpTableBase = allocateSpace(NumEntries * EntrySize, MJTI->getAlignment());
1401 void JITEmitter::emitJumpTableInfo(MachineJumpTableInfo *MJTI) {
1402 if (TheJIT->getJITInfo().hasCustomJumpTables())
1405 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1406 if (JT.empty() || JumpTableBase == 0) return;
1408 if (TargetMachine::getRelocationModel() == Reloc::PIC_) {
1409 assert(MJTI->getEntrySize() == 4 && "Cross JIT'ing?");
1410 // For each jump table, place the offset from the beginning of the table
1411 // to the target address.
1412 int *SlotPtr = (int*)JumpTableBase;
1414 for (unsigned i = 0, e = JT.size(); i != e; ++i) {
1415 const std::vector<MachineBasicBlock*> &MBBs = JT[i].MBBs;
1416 // Store the offset of the basic block for this jump table slot in the
1417 // memory we allocated for the jump table in 'initJumpTableInfo'
1418 uintptr_t Base = (uintptr_t)SlotPtr;
1419 for (unsigned mi = 0, me = MBBs.size(); mi != me; ++mi) {
1420 uintptr_t MBBAddr = getMachineBasicBlockAddress(MBBs[mi]);
1421 *SlotPtr++ = TheJIT->getJITInfo().getPICJumpTableEntry(MBBAddr, Base);
1425 assert(MJTI->getEntrySize() == sizeof(void*) && "Cross JIT'ing?");
1427 // For each jump table, map each target in the jump table to the address of
1428 // an emitted MachineBasicBlock.
1429 intptr_t *SlotPtr = (intptr_t*)JumpTableBase;
1431 for (unsigned i = 0, e = JT.size(); i != e; ++i) {
1432 const std::vector<MachineBasicBlock*> &MBBs = JT[i].MBBs;
1433 // Store the address of the basic block for this jump table slot in the
1434 // memory we allocated for the jump table in 'initJumpTableInfo'
1435 for (unsigned mi = 0, me = MBBs.size(); mi != me; ++mi)
1436 *SlotPtr++ = getMachineBasicBlockAddress(MBBs[mi]);
1441 void JITEmitter::startGVStub(BufferState &BS, const GlobalValue* GV,
1442 unsigned StubSize, unsigned Alignment) {
1445 BufferBegin = CurBufferPtr = MemMgr->allocateStub(GV, StubSize, Alignment);
1446 BufferEnd = BufferBegin+StubSize+1;
1449 void JITEmitter::startGVStub(BufferState &BS, void *Buffer, unsigned StubSize) {
1452 BufferBegin = CurBufferPtr = (uint8_t *)Buffer;
1453 BufferEnd = BufferBegin+StubSize+1;
1456 void *JITEmitter::finishGVStub(BufferState &BS) {
1457 assert(CurBufferPtr != BufferEnd && "Stub overflowed allocated space.");
1458 NumBytes += getCurrentPCOffset();
1459 void *Result = BufferBegin;
1460 RestoreStateFrom(BS);
1464 // getConstantPoolEntryAddress - Return the address of the 'ConstantNum' entry
1465 // in the constant pool that was last emitted with the 'emitConstantPool'
1468 uintptr_t JITEmitter::getConstantPoolEntryAddress(unsigned ConstantNum) const {
1469 assert(ConstantNum < ConstantPool->getConstants().size() &&
1470 "Invalid ConstantPoolIndex!");
1471 return ConstPoolAddresses[ConstantNum];
1474 // getJumpTableEntryAddress - Return the address of the JumpTable with index
1475 // 'Index' in the jumpp table that was last initialized with 'initJumpTableInfo'
1477 uintptr_t JITEmitter::getJumpTableEntryAddress(unsigned Index) const {
1478 const std::vector<MachineJumpTableEntry> &JT = JumpTable->getJumpTables();
1479 assert(Index < JT.size() && "Invalid jump table index!");
1481 unsigned Offset = 0;
1482 unsigned EntrySize = JumpTable->getEntrySize();
1484 for (unsigned i = 0; i < Index; ++i)
1485 Offset += JT[i].MBBs.size();
1487 Offset *= EntrySize;
1489 return (uintptr_t)((char *)JumpTableBase + Offset);
1492 void JITEmitter::EmittedFunctionConfig::onDelete(
1493 JITEmitter *Emitter, const Function *F) {
1494 Emitter->deallocateMemForFunction(F);
1496 void JITEmitter::EmittedFunctionConfig::onRAUW(
1497 JITEmitter *, const Function*, const Function*) {
1498 llvm_unreachable("The JIT doesn't know how to handle a"
1499 " RAUW on a value it has emitted.");
1503 //===----------------------------------------------------------------------===//
1504 // Public interface to this file
1505 //===----------------------------------------------------------------------===//
1507 JITCodeEmitter *JIT::createEmitter(JIT &jit, JITMemoryManager *JMM,
1508 TargetMachine &tm) {
1509 return new JITEmitter(jit, JMM, tm);
1512 // getPointerToNamedFunction - This function is used as a global wrapper to
1513 // JIT::getPointerToNamedFunction for the purpose of resolving symbols when
1514 // bugpoint is debugging the JIT. In that scenario, we are loading an .so and
1515 // need to resolve function(s) that are being mis-codegenerated, so we need to
1516 // resolve their addresses at runtime, and this is the way to do it.
1518 void *getPointerToNamedFunction(const char *Name) {
1519 if (Function *F = TheJIT->FindFunctionNamed(Name))
1520 return TheJIT->getPointerToFunction(F);
1521 return TheJIT->getPointerToNamedFunction(Name);
1525 // getPointerToFunctionOrStub - If the specified function has been
1526 // code-gen'd, return a pointer to the function. If not, compile it, or use
1527 // a stub to implement lazy compilation if available.
1529 void *JIT::getPointerToFunctionOrStub(Function *F) {
1530 // If we have already code generated the function, just return the address.
1531 if (void *Addr = getPointerToGlobalIfAvailable(F))
1534 // Get a stub if the target supports it.
1535 assert(isa<JITEmitter>(JCE) && "Unexpected MCE?");
1536 JITEmitter *JE = cast<JITEmitter>(getCodeEmitter());
1537 return JE->getJITResolver().getLazyFunctionStub(F);
1540 void JIT::updateFunctionStub(Function *F) {
1541 // Get the empty stub we generated earlier.
1542 assert(isa<JITEmitter>(JCE) && "Unexpected MCE?");
1543 JITEmitter *JE = cast<JITEmitter>(getCodeEmitter());
1544 void *Stub = JE->getJITResolver().getLazyFunctionStub(F);
1545 void *Addr = getPointerToGlobalIfAvailable(F);
1547 // Tell the target jit info to rewrite the stub at the specified address,
1548 // rather than creating a new one.
1549 MachineCodeEmitter::BufferState BS;
1550 TargetJITInfo::StubLayout layout = getJITInfo().getStubLayout();
1551 JE->startGVStub(BS, Stub, layout.Size);
1552 getJITInfo().emitFunctionStub(F, Addr, *getCodeEmitter());
1553 JE->finishGVStub(BS);
1556 /// freeMachineCodeForFunction - release machine code memory for given Function.
1558 void JIT::freeMachineCodeForFunction(Function *F) {
1559 // Delete translation for this from the ExecutionEngine, so it will get
1560 // retranslated next time it is used.
1561 updateGlobalMapping(F, 0);
1563 // Free the actual memory for the function body and related stuff.
1564 assert(isa<JITEmitter>(JCE) && "Unexpected MCE?");
1565 cast<JITEmitter>(JCE)->deallocateMemForFunction(F);