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/Analysis/DebugInfo.h"
24 #include "llvm/CodeGen/JITCodeEmitter.h"
25 #include "llvm/CodeGen/MachineFunction.h"
26 #include "llvm/CodeGen/MachineCodeInfo.h"
27 #include "llvm/CodeGen/MachineConstantPool.h"
28 #include "llvm/CodeGen/MachineJumpTableInfo.h"
29 #include "llvm/CodeGen/MachineModuleInfo.h"
30 #include "llvm/CodeGen/MachineRelocation.h"
31 #include "llvm/ExecutionEngine/GenericValue.h"
32 #include "llvm/ExecutionEngine/JITEventListener.h"
33 #include "llvm/ExecutionEngine/JITMemoryManager.h"
34 #include "llvm/Target/TargetData.h"
35 #include "llvm/Target/TargetInstrInfo.h"
36 #include "llvm/Target/TargetJITInfo.h"
37 #include "llvm/Target/TargetMachine.h"
38 #include "llvm/Target/TargetOptions.h"
39 #include "llvm/Support/Debug.h"
40 #include "llvm/Support/ErrorHandling.h"
41 #include "llvm/Support/ManagedStatic.h"
42 #include "llvm/Support/MutexGuard.h"
43 #include "llvm/Support/ValueHandle.h"
44 #include "llvm/Support/raw_ostream.h"
45 #include "llvm/Support/Disassembler.h"
46 #include "llvm/Support/Memory.h"
47 #include "llvm/ADT/DenseMap.h"
48 #include "llvm/ADT/SmallPtrSet.h"
49 #include "llvm/ADT/SmallVector.h"
50 #include "llvm/ADT/Statistic.h"
51 #include "llvm/ADT/ValueMap.h"
58 STATISTIC(NumBytes
, "Number of bytes of machine code compiled");
59 STATISTIC(NumRelos
, "Number of relocations applied");
60 STATISTIC(NumRetries
, "Number of retries with more memory");
63 // A declaration may stop being a declaration once it's fully read from bitcode.
64 // This function returns true if F is fully read and is still a declaration.
65 static bool isNonGhostDeclaration(const Function
*F
) {
66 return F
->isDeclaration() && !F
->isMaterializable();
69 //===----------------------------------------------------------------------===//
70 // JIT lazy compilation code.
74 class JITResolverState
;
76 template<typename ValueTy
>
77 struct NoRAUWValueMapConfig
: public ValueMapConfig
<ValueTy
> {
78 typedef JITResolverState
*ExtraData
;
79 static void onRAUW(JITResolverState
*, Value
*Old
, Value
*New
) {
80 assert(false && "The JIT doesn't know how to handle a"
81 " RAUW on a value it has emitted.");
85 struct CallSiteValueMapConfig
: public NoRAUWValueMapConfig
<Function
*> {
86 typedef JITResolverState
*ExtraData
;
87 static void onDelete(JITResolverState
*JRS
, Function
*F
);
90 class JITResolverState
{
92 typedef ValueMap
<Function
*, void*, NoRAUWValueMapConfig
<Function
*> >
93 FunctionToLazyStubMapTy
;
94 typedef std::map
<void*, AssertingVH
<Function
> > CallSiteToFunctionMapTy
;
95 typedef ValueMap
<Function
*, SmallPtrSet
<void*, 1>,
96 CallSiteValueMapConfig
> FunctionToCallSitesMapTy
;
97 typedef std::map
<AssertingVH
<GlobalValue
>, void*> GlobalToIndirectSymMapTy
;
99 /// FunctionToLazyStubMap - Keep track of the lazy stub created for a
100 /// particular function so that we can reuse them if necessary.
101 FunctionToLazyStubMapTy FunctionToLazyStubMap
;
103 /// CallSiteToFunctionMap - Keep track of the function that each lazy call
104 /// site corresponds to, and vice versa.
105 CallSiteToFunctionMapTy CallSiteToFunctionMap
;
106 FunctionToCallSitesMapTy FunctionToCallSitesMap
;
108 /// GlobalToIndirectSymMap - Keep track of the indirect symbol created for a
109 /// particular GlobalVariable so that we can reuse them if necessary.
110 GlobalToIndirectSymMapTy GlobalToIndirectSymMap
;
112 /// Instance of the JIT this ResolverState serves.
116 JITResolverState(JIT
*jit
) : FunctionToLazyStubMap(this),
117 FunctionToCallSitesMap(this),
120 FunctionToLazyStubMapTy
& getFunctionToLazyStubMap(
121 const MutexGuard
& locked
) {
122 assert(locked
.holds(TheJIT
->lock
));
123 return FunctionToLazyStubMap
;
126 GlobalToIndirectSymMapTy
& getGlobalToIndirectSymMap(const MutexGuard
& lck
) {
127 assert(lck
.holds(TheJIT
->lock
));
128 return GlobalToIndirectSymMap
;
131 std::pair
<void *, Function
*> LookupFunctionFromCallSite(
132 const MutexGuard
&locked
, void *CallSite
) const {
133 assert(locked
.holds(TheJIT
->lock
));
135 // The address given to us for the stub may not be exactly right, it
136 // might be a little bit after the stub. As such, use upper_bound to
138 CallSiteToFunctionMapTy::const_iterator I
=
139 CallSiteToFunctionMap
.upper_bound(CallSite
);
140 assert(I
!= CallSiteToFunctionMap
.begin() &&
141 "This is not a known call site!");
146 void AddCallSite(const MutexGuard
&locked
, void *CallSite
, Function
*F
) {
147 assert(locked
.holds(TheJIT
->lock
));
149 bool Inserted
= CallSiteToFunctionMap
.insert(
150 std::make_pair(CallSite
, F
)).second
;
152 assert(Inserted
&& "Pair was already in CallSiteToFunctionMap");
153 FunctionToCallSitesMap
[F
].insert(CallSite
);
156 void EraseAllCallSitesForPrelocked(Function
*F
);
158 // Erases _all_ call sites regardless of their function. This is used to
159 // unregister the stub addresses from the StubToResolverMap in
161 void EraseAllCallSitesPrelocked();
164 /// JITResolver - Keep track of, and resolve, call sites for functions that
165 /// have not yet been compiled.
167 typedef JITResolverState::FunctionToLazyStubMapTy FunctionToLazyStubMapTy
;
168 typedef JITResolverState::CallSiteToFunctionMapTy CallSiteToFunctionMapTy
;
169 typedef JITResolverState::GlobalToIndirectSymMapTy GlobalToIndirectSymMapTy
;
171 /// LazyResolverFn - The target lazy resolver function that we actually
172 /// rewrite instructions to use.
173 TargetJITInfo::LazyResolverFn LazyResolverFn
;
175 JITResolverState state
;
177 /// ExternalFnToStubMap - This is the equivalent of FunctionToLazyStubMap
178 /// for external functions. TODO: Of course, external functions don't need
179 /// a lazy stub. It's actually here to make it more likely that far calls
180 /// succeed, but no single stub can guarantee that. I'll remove this in a
181 /// subsequent checkin when I actually fix far calls.
182 std::map
<void*, void*> ExternalFnToStubMap
;
184 /// revGOTMap - map addresses to indexes in the GOT
185 std::map
<void*, unsigned> revGOTMap
;
186 unsigned nextGOTIndex
;
190 /// Instance of JIT corresponding to this Resolver.
194 explicit JITResolver(JIT
&jit
, JITEmitter
&je
)
195 : state(&jit
), nextGOTIndex(0), JE(je
), TheJIT(&jit
) {
196 LazyResolverFn
= jit
.getJITInfo().getLazyResolverFunction(JITCompilerFn
);
201 /// getLazyFunctionStubIfAvailable - This returns a pointer to a function's
202 /// lazy-compilation stub if it has already been created.
203 void *getLazyFunctionStubIfAvailable(Function
*F
);
205 /// getLazyFunctionStub - This returns a pointer to a function's
206 /// lazy-compilation stub, creating one on demand as needed.
207 void *getLazyFunctionStub(Function
*F
);
209 /// getExternalFunctionStub - Return a stub for the function at the
210 /// specified address, created lazily on demand.
211 void *getExternalFunctionStub(void *FnAddr
);
213 /// getGlobalValueIndirectSym - Return an indirect symbol containing the
214 /// specified GV address.
215 void *getGlobalValueIndirectSym(GlobalValue
*V
, void *GVAddress
);
217 /// getGOTIndexForAddress - Return a new or existing index in the GOT for
218 /// an address. This function only manages slots, it does not manage the
219 /// contents of the slots or the memory associated with the GOT.
220 unsigned getGOTIndexForAddr(void *addr
);
222 /// JITCompilerFn - This function is called to resolve a stub to a compiled
223 /// address. If the LLVM Function corresponding to the stub has not yet
224 /// been compiled, this function compiles it first.
225 static void *JITCompilerFn(void *Stub
);
228 class StubToResolverMapTy
{
229 /// Map a stub address to a specific instance of a JITResolver so that
230 /// lazily-compiled functions can find the right resolver to use.
233 std::map
<void*, JITResolver
*> Map
;
235 /// Guards Map from concurrent accesses.
236 mutable sys::Mutex Lock
;
239 /// Registers a Stub to be resolved by Resolver.
240 void RegisterStubResolver(void *Stub
, JITResolver
*Resolver
) {
241 MutexGuard
guard(Lock
);
242 Map
.insert(std::make_pair(Stub
, Resolver
));
244 /// Unregisters the Stub when it's invalidated.
245 void UnregisterStubResolver(void *Stub
) {
246 MutexGuard
guard(Lock
);
249 /// Returns the JITResolver instance that owns the Stub.
250 JITResolver
*getResolverFromStub(void *Stub
) const {
251 MutexGuard
guard(Lock
);
252 // The address given to us for the stub may not be exactly right, it might
253 // be a little bit after the stub. As such, use upper_bound to find it.
254 // This is the same trick as in LookupFunctionFromCallSite from
256 std::map
<void*, JITResolver
*>::const_iterator I
= Map
.upper_bound(Stub
);
257 assert(I
!= Map
.begin() && "This is not a known stub!");
261 /// True if any stubs refer to the given resolver. Only used in an assert().
263 bool ResolverHasStubs(JITResolver
* Resolver
) const {
264 MutexGuard
guard(Lock
);
265 for (std::map
<void*, JITResolver
*>::const_iterator I
= Map
.begin(),
266 E
= Map
.end(); I
!= E
; ++I
) {
267 if (I
->second
== Resolver
)
273 /// This needs to be static so that a lazy call stub can access it with no
274 /// context except the address of the stub.
275 ManagedStatic
<StubToResolverMapTy
> StubToResolverMap
;
277 /// JITEmitter - The JIT implementation of the MachineCodeEmitter, which is
278 /// used to output functions to memory for execution.
279 class JITEmitter
: public JITCodeEmitter
{
280 JITMemoryManager
*MemMgr
;
282 // When outputting a function stub in the context of some other function, we
283 // save BufferBegin/BufferEnd/CurBufferPtr here.
284 uint8_t *SavedBufferBegin
, *SavedBufferEnd
, *SavedCurBufferPtr
;
286 // When reattempting to JIT a function after running out of space, we store
287 // the estimated size of the function we're trying to JIT here, so we can
288 // ask the memory manager for at least this much space. When we
289 // successfully emit the function, we reset this back to zero.
290 uintptr_t SizeEstimate
;
292 /// Relocations - These are the relocations that the function needs, as
294 std::vector
<MachineRelocation
> Relocations
;
296 /// MBBLocations - This vector is a mapping from MBB ID's to their address.
297 /// It is filled in by the StartMachineBasicBlock callback and queried by
298 /// the getMachineBasicBlockAddress callback.
299 std::vector
<uintptr_t> MBBLocations
;
301 /// ConstantPool - The constant pool for the current function.
303 MachineConstantPool
*ConstantPool
;
305 /// ConstantPoolBase - A pointer to the first entry in the constant pool.
307 void *ConstantPoolBase
;
309 /// ConstPoolAddresses - Addresses of individual constant pool entries.
311 SmallVector
<uintptr_t, 8> ConstPoolAddresses
;
313 /// JumpTable - The jump tables for the current function.
315 MachineJumpTableInfo
*JumpTable
;
317 /// JumpTableBase - A pointer to the first entry in the jump table.
321 /// Resolver - This contains info about the currently resolved functions.
322 JITResolver Resolver
;
324 /// DE - The dwarf emitter for the jit.
325 OwningPtr
<JITDwarfEmitter
> DE
;
327 /// DR - The debug registerer for the jit.
328 OwningPtr
<JITDebugRegisterer
> DR
;
330 /// LabelLocations - This vector is a mapping from Label ID's to their
332 DenseMap
<MCSymbol
*, uintptr_t> LabelLocations
;
334 /// MMI - Machine module info for exception informations
335 MachineModuleInfo
* MMI
;
337 // CurFn - The llvm function being emitted. Only valid during
339 const Function
*CurFn
;
341 /// Information about emitted code, which is passed to the
342 /// JITEventListeners. This is reset in startFunction and used in
344 JITEvent_EmittedFunctionDetails EmissionDetails
;
347 void *FunctionBody
; // Beginning of the function's allocation.
348 void *Code
; // The address the function's code actually starts at.
349 void *ExceptionTable
;
350 EmittedCode() : FunctionBody(0), Code(0), ExceptionTable(0) {}
352 struct EmittedFunctionConfig
: public ValueMapConfig
<const Function
*> {
353 typedef JITEmitter
*ExtraData
;
354 static void onDelete(JITEmitter
*, const Function
*);
355 static void onRAUW(JITEmitter
*, const Function
*, const Function
*);
357 ValueMap
<const Function
*, EmittedCode
,
358 EmittedFunctionConfig
> EmittedFunctions
;
362 /// Instance of the JIT
366 JITEmitter(JIT
&jit
, JITMemoryManager
*JMM
, TargetMachine
&TM
)
367 : SizeEstimate(0), Resolver(jit
, *this), MMI(0), CurFn(0),
368 EmittedFunctions(this), TheJIT(&jit
) {
369 MemMgr
= JMM
? JMM
: JITMemoryManager::CreateDefaultMemManager();
370 if (jit
.getJITInfo().needsGOT()) {
371 MemMgr
->AllocateGOT();
372 DEBUG(dbgs() << "JIT is managing a GOT\n");
375 if (JITExceptionHandling
|| JITEmitDebugInfo
) {
376 DE
.reset(new JITDwarfEmitter(jit
));
378 if (JITEmitDebugInfo
) {
379 DR
.reset(new JITDebugRegisterer(TM
));
386 /// classof - Methods for support type inquiry through isa, cast, and
389 static inline bool classof(const MachineCodeEmitter
*) { return true; }
391 JITResolver
&getJITResolver() { return Resolver
; }
393 virtual void startFunction(MachineFunction
&F
);
394 virtual bool finishFunction(MachineFunction
&F
);
396 void emitConstantPool(MachineConstantPool
*MCP
);
397 void initJumpTableInfo(MachineJumpTableInfo
*MJTI
);
398 void emitJumpTableInfo(MachineJumpTableInfo
*MJTI
);
400 void startGVStub(const GlobalValue
* GV
,
401 unsigned StubSize
, unsigned Alignment
= 1);
402 void startGVStub(void *Buffer
, unsigned StubSize
);
404 virtual void *allocIndirectGV(const GlobalValue
*GV
,
405 const uint8_t *Buffer
, size_t Size
,
408 /// allocateSpace - Reserves space in the current block if any, or
409 /// allocate a new one of the given size.
410 virtual void *allocateSpace(uintptr_t Size
, unsigned Alignment
);
412 /// allocateGlobal - Allocate memory for a global. Unlike allocateSpace,
413 /// this method does not allocate memory in the current output buffer,
414 /// because a global may live longer than the current function.
415 virtual void *allocateGlobal(uintptr_t Size
, unsigned Alignment
);
417 virtual void addRelocation(const MachineRelocation
&MR
) {
418 Relocations
.push_back(MR
);
421 virtual void StartMachineBasicBlock(MachineBasicBlock
*MBB
) {
422 if (MBBLocations
.size() <= (unsigned)MBB
->getNumber())
423 MBBLocations
.resize((MBB
->getNumber()+1)*2);
424 MBBLocations
[MBB
->getNumber()] = getCurrentPCValue();
425 if (MBB
->hasAddressTaken())
426 TheJIT
->addPointerToBasicBlock(MBB
->getBasicBlock(),
427 (void*)getCurrentPCValue());
428 DEBUG(dbgs() << "JIT: Emitting BB" << MBB
->getNumber() << " at ["
429 << (void*) getCurrentPCValue() << "]\n");
432 virtual uintptr_t getConstantPoolEntryAddress(unsigned Entry
) const;
433 virtual uintptr_t getJumpTableEntryAddress(unsigned Entry
) const;
435 virtual uintptr_t getMachineBasicBlockAddress(MachineBasicBlock
*MBB
) const{
436 assert(MBBLocations
.size() > (unsigned)MBB
->getNumber() &&
437 MBBLocations
[MBB
->getNumber()] && "MBB not emitted!");
438 return MBBLocations
[MBB
->getNumber()];
441 /// retryWithMoreMemory - Log a retry and deallocate all memory for the
442 /// given function. Increase the minimum allocation size so that we get
443 /// more memory next time.
444 void retryWithMoreMemory(MachineFunction
&F
);
446 /// deallocateMemForFunction - Deallocate all memory for the specified
448 void deallocateMemForFunction(const Function
*F
);
450 virtual void processDebugLoc(DebugLoc DL
, bool BeforePrintingInsn
);
452 virtual void emitLabel(MCSymbol
*Label
) {
453 LabelLocations
[Label
] = getCurrentPCValue();
456 virtual DenseMap
<MCSymbol
*, uintptr_t> *getLabelLocations() {
457 return &LabelLocations
;
460 virtual uintptr_t getLabelAddress(MCSymbol
*Label
) const {
461 assert(LabelLocations
.count(Label
) && "Label not emitted!");
462 return LabelLocations
.find(Label
)->second
;
465 virtual void setModuleInfo(MachineModuleInfo
* Info
) {
467 if (DE
.get()) DE
->setModuleInfo(Info
);
471 void *getPointerToGlobal(GlobalValue
*GV
, void *Reference
,
472 bool MayNeedFarStub
);
473 void *getPointerToGVIndirectSym(GlobalValue
*V
, void *Reference
);
477 void CallSiteValueMapConfig::onDelete(JITResolverState
*JRS
, Function
*F
) {
478 JRS
->EraseAllCallSitesForPrelocked(F
);
481 void JITResolverState::EraseAllCallSitesForPrelocked(Function
*F
) {
482 FunctionToCallSitesMapTy::iterator F2C
= FunctionToCallSitesMap
.find(F
);
483 if (F2C
== FunctionToCallSitesMap
.end())
485 StubToResolverMapTy
&S2RMap
= *StubToResolverMap
;
486 for (SmallPtrSet
<void*, 1>::const_iterator I
= F2C
->second
.begin(),
487 E
= F2C
->second
.end(); I
!= E
; ++I
) {
488 S2RMap
.UnregisterStubResolver(*I
);
489 bool Erased
= CallSiteToFunctionMap
.erase(*I
);
491 assert(Erased
&& "Missing call site->function mapping");
493 FunctionToCallSitesMap
.erase(F2C
);
496 void JITResolverState::EraseAllCallSitesPrelocked() {
497 StubToResolverMapTy
&S2RMap
= *StubToResolverMap
;
498 for (CallSiteToFunctionMapTy::const_iterator
499 I
= CallSiteToFunctionMap
.begin(),
500 E
= CallSiteToFunctionMap
.end(); I
!= E
; ++I
) {
501 S2RMap
.UnregisterStubResolver(I
->first
);
503 CallSiteToFunctionMap
.clear();
504 FunctionToCallSitesMap
.clear();
507 JITResolver::~JITResolver() {
508 // No need to lock because we're in the destructor, and state isn't shared.
509 state
.EraseAllCallSitesPrelocked();
510 assert(!StubToResolverMap
->ResolverHasStubs(this) &&
511 "Resolver destroyed with stubs still alive.");
514 /// getLazyFunctionStubIfAvailable - This returns a pointer to a function stub
515 /// if it has already been created.
516 void *JITResolver::getLazyFunctionStubIfAvailable(Function
*F
) {
517 MutexGuard
locked(TheJIT
->lock
);
519 // If we already have a stub for this function, recycle it.
520 return state
.getFunctionToLazyStubMap(locked
).lookup(F
);
523 /// getFunctionStub - This returns a pointer to a function stub, creating
524 /// one on demand as needed.
525 void *JITResolver::getLazyFunctionStub(Function
*F
) {
526 MutexGuard
locked(TheJIT
->lock
);
528 // If we already have a lazy stub for this function, recycle it.
529 void *&Stub
= state
.getFunctionToLazyStubMap(locked
)[F
];
530 if (Stub
) return Stub
;
532 // Call the lazy resolver function if we are JIT'ing lazily. Otherwise we
533 // must resolve the symbol now.
534 void *Actual
= TheJIT
->isCompilingLazily()
535 ? (void *)(intptr_t)LazyResolverFn
: (void *)0;
537 // If this is an external declaration, attempt to resolve the address now
538 // to place in the stub.
539 if (isNonGhostDeclaration(F
) || F
->hasAvailableExternallyLinkage()) {
540 Actual
= TheJIT
->getPointerToFunction(F
);
542 // If we resolved the symbol to a null address (eg. a weak external)
543 // don't emit a stub. Return a null pointer to the application.
544 if (!Actual
) return 0;
547 TargetJITInfo::StubLayout SL
= TheJIT
->getJITInfo().getStubLayout();
548 JE
.startGVStub(F
, SL
.Size
, SL
.Alignment
);
549 // Codegen a new stub, calling the lazy resolver or the actual address of the
550 // external function, if it was resolved.
551 Stub
= TheJIT
->getJITInfo().emitFunctionStub(F
, Actual
, JE
);
554 if (Actual
!= (void*)(intptr_t)LazyResolverFn
) {
555 // If we are getting the stub for an external function, we really want the
556 // address of the stub in the GlobalAddressMap for the JIT, not the address
557 // of the external function.
558 TheJIT
->updateGlobalMapping(F
, Stub
);
561 DEBUG(dbgs() << "JIT: Lazy stub emitted at [" << Stub
<< "] for function '"
562 << F
->getName() << "'\n");
564 if (TheJIT
->isCompilingLazily()) {
565 // Register this JITResolver as the one corresponding to this call site so
566 // JITCompilerFn will be able to find it.
567 StubToResolverMap
->RegisterStubResolver(Stub
, this);
569 // Finally, keep track of the stub-to-Function mapping so that the
570 // JITCompilerFn knows which function to compile!
571 state
.AddCallSite(locked
, Stub
, F
);
572 } else if (!Actual
) {
573 // If we are JIT'ing non-lazily but need to call a function that does not
574 // exist yet, add it to the JIT's work list so that we can fill in the
575 // stub address later.
576 assert(!isNonGhostDeclaration(F
) && !F
->hasAvailableExternallyLinkage() &&
577 "'Actual' should have been set above.");
578 TheJIT
->addPendingFunction(F
);
584 /// getGlobalValueIndirectSym - Return a lazy pointer containing the specified
586 void *JITResolver::getGlobalValueIndirectSym(GlobalValue
*GV
, void *GVAddress
) {
587 MutexGuard
locked(TheJIT
->lock
);
589 // If we already have a stub for this global variable, recycle it.
590 void *&IndirectSym
= state
.getGlobalToIndirectSymMap(locked
)[GV
];
591 if (IndirectSym
) return IndirectSym
;
593 // Otherwise, codegen a new indirect symbol.
594 IndirectSym
= TheJIT
->getJITInfo().emitGlobalValueIndirectSym(GV
, GVAddress
,
597 DEBUG(dbgs() << "JIT: Indirect symbol emitted at [" << IndirectSym
598 << "] for GV '" << GV
->getName() << "'\n");
603 /// getExternalFunctionStub - Return a stub for the function at the
604 /// specified address, created lazily on demand.
605 void *JITResolver::getExternalFunctionStub(void *FnAddr
) {
606 // If we already have a stub for this function, recycle it.
607 void *&Stub
= ExternalFnToStubMap
[FnAddr
];
608 if (Stub
) return Stub
;
610 TargetJITInfo::StubLayout SL
= TheJIT
->getJITInfo().getStubLayout();
611 JE
.startGVStub(0, SL
.Size
, SL
.Alignment
);
612 Stub
= TheJIT
->getJITInfo().emitFunctionStub(0, FnAddr
, JE
);
615 DEBUG(dbgs() << "JIT: Stub emitted at [" << Stub
616 << "] for external function at '" << FnAddr
<< "'\n");
620 unsigned JITResolver::getGOTIndexForAddr(void* addr
) {
621 unsigned idx
= revGOTMap
[addr
];
623 idx
= ++nextGOTIndex
;
624 revGOTMap
[addr
] = idx
;
625 DEBUG(dbgs() << "JIT: Adding GOT entry " << idx
<< " for addr ["
631 /// JITCompilerFn - This function is called when a lazy compilation stub has
632 /// been entered. It looks up which function this stub corresponds to, compiles
633 /// it if necessary, then returns the resultant function pointer.
634 void *JITResolver::JITCompilerFn(void *Stub
) {
635 JITResolver
*JR
= StubToResolverMap
->getResolverFromStub(Stub
);
636 assert(JR
&& "Unable to find the corresponding JITResolver to the call site");
642 // Only lock for getting the Function. The call getPointerToFunction made
643 // in this function might trigger function materializing, which requires
644 // JIT lock to be unlocked.
645 MutexGuard
locked(JR
->TheJIT
->lock
);
647 // The address given to us for the stub may not be exactly right, it might
648 // be a little bit after the stub. As such, use upper_bound to find it.
649 std::pair
<void*, Function
*> I
=
650 JR
->state
.LookupFunctionFromCallSite(locked
, Stub
);
655 // If we have already code generated the function, just return the address.
656 void *Result
= JR
->TheJIT
->getPointerToGlobalIfAvailable(F
);
659 // Otherwise we don't have it, do lazy compilation now.
661 // If lazy compilation is disabled, emit a useful error message and abort.
662 if (!JR
->TheJIT
->isCompilingLazily()) {
663 report_fatal_error("LLVM JIT requested to do lazy compilation of"
665 + F
->getName() + "' when lazy compiles are disabled!");
668 DEBUG(dbgs() << "JIT: Lazily resolving function '" << F
->getName()
669 << "' In stub ptr = " << Stub
<< " actual ptr = "
670 << ActualPtr
<< "\n");
672 Result
= JR
->TheJIT
->getPointerToFunction(F
);
675 // Reacquire the lock to update the GOT map.
676 MutexGuard
locked(JR
->TheJIT
->lock
);
678 // We might like to remove the call site from the CallSiteToFunction map, but
679 // we can't do that! Multiple threads could be stuck, waiting to acquire the
680 // lock above. As soon as the 1st function finishes compiling the function,
681 // the next one will be released, and needs to be able to find the function it
684 // FIXME: We could rewrite all references to this stub if we knew them.
686 // What we will do is set the compiled function address to map to the
687 // same GOT entry as the stub so that later clients may update the GOT
688 // if they see it still using the stub address.
689 // Note: this is done so the Resolver doesn't have to manage GOT memory
690 // Do this without allocating map space if the target isn't using a GOT
691 if(JR
->revGOTMap
.find(Stub
) != JR
->revGOTMap
.end())
692 JR
->revGOTMap
[Result
] = JR
->revGOTMap
[Stub
];
697 //===----------------------------------------------------------------------===//
700 void *JITEmitter::getPointerToGlobal(GlobalValue
*V
, void *Reference
,
701 bool MayNeedFarStub
) {
702 if (GlobalVariable
*GV
= dyn_cast
<GlobalVariable
>(V
))
703 return TheJIT
->getOrEmitGlobalVariable(GV
);
705 if (GlobalAlias
*GA
= dyn_cast
<GlobalAlias
>(V
))
706 return TheJIT
->getPointerToGlobal(GA
->resolveAliasedGlobal(false));
708 // If we have already compiled the function, return a pointer to its body.
709 Function
*F
= cast
<Function
>(V
);
711 void *FnStub
= Resolver
.getLazyFunctionStubIfAvailable(F
);
713 // Return the function stub if it's already created. We do this first so
714 // that we're returning the same address for the function as any previous
715 // call. TODO: Yes, this is wrong. The lazy stub isn't guaranteed to be
716 // close enough to call.
720 // If we know the target can handle arbitrary-distance calls, try to
721 // return a direct pointer.
722 if (!MayNeedFarStub
) {
723 // If we have code, go ahead and return that.
724 void *ResultPtr
= TheJIT
->getPointerToGlobalIfAvailable(F
);
725 if (ResultPtr
) return ResultPtr
;
727 // If this is an external function pointer, we can force the JIT to
728 // 'compile' it, which really just adds it to the map.
729 if (isNonGhostDeclaration(F
) || F
->hasAvailableExternallyLinkage())
730 return TheJIT
->getPointerToFunction(F
);
733 // Otherwise, we may need a to emit a stub, and, conservatively, we always do
734 // so. Note that it's possible to return null from getLazyFunctionStub in the
735 // case of a weak extern that fails to resolve.
736 return Resolver
.getLazyFunctionStub(F
);
739 void *JITEmitter::getPointerToGVIndirectSym(GlobalValue
*V
, void *Reference
) {
740 // Make sure GV is emitted first, and create a stub containing the fully
742 void *GVAddress
= getPointerToGlobal(V
, Reference
, false);
743 void *StubAddr
= Resolver
.getGlobalValueIndirectSym(V
, GVAddress
);
747 void JITEmitter::processDebugLoc(DebugLoc DL
, bool BeforePrintingInsn
) {
748 if (DL
.isUnknown()) return;
749 if (!BeforePrintingInsn
) return;
751 const LLVMContext
&Context
= EmissionDetails
.MF
->getFunction()->getContext();
753 if (DL
.getScope(Context
) != 0 && PrevDL
!= DL
) {
754 JITEvent_EmittedFunctionDetails::LineStart NextLine
;
755 NextLine
.Address
= getCurrentPCValue();
757 EmissionDetails
.LineStarts
.push_back(NextLine
);
763 static unsigned GetConstantPoolSizeInBytes(MachineConstantPool
*MCP
,
764 const TargetData
*TD
) {
765 const std::vector
<MachineConstantPoolEntry
> &Constants
= MCP
->getConstants();
766 if (Constants
.empty()) return 0;
769 for (unsigned i
= 0, e
= Constants
.size(); i
!= e
; ++i
) {
770 MachineConstantPoolEntry CPE
= Constants
[i
];
771 unsigned AlignMask
= CPE
.getAlignment() - 1;
772 Size
= (Size
+ AlignMask
) & ~AlignMask
;
773 const Type
*Ty
= CPE
.getType();
774 Size
+= TD
->getTypeAllocSize(Ty
);
779 void JITEmitter::startFunction(MachineFunction
&F
) {
780 DEBUG(dbgs() << "JIT: Starting CodeGen of Function "
781 << F
.getFunction()->getName() << "\n");
783 uintptr_t ActualSize
= 0;
784 // Set the memory writable, if it's not already
785 MemMgr
->setMemoryWritable();
787 if (SizeEstimate
> 0) {
788 // SizeEstimate will be non-zero on reallocation attempts.
789 ActualSize
= SizeEstimate
;
792 BufferBegin
= CurBufferPtr
= MemMgr
->startFunctionBody(F
.getFunction(),
794 BufferEnd
= BufferBegin
+ActualSize
;
795 EmittedFunctions
[F
.getFunction()].FunctionBody
= BufferBegin
;
797 // Ensure the constant pool/jump table info is at least 4-byte aligned.
800 emitConstantPool(F
.getConstantPool());
801 if (MachineJumpTableInfo
*MJTI
= F
.getJumpTableInfo())
802 initJumpTableInfo(MJTI
);
804 // About to start emitting the machine code for the function.
805 emitAlignment(std::max(F
.getFunction()->getAlignment(), 8U));
806 TheJIT
->updateGlobalMapping(F
.getFunction(), CurBufferPtr
);
807 EmittedFunctions
[F
.getFunction()].Code
= CurBufferPtr
;
809 MBBLocations
.clear();
811 EmissionDetails
.MF
= &F
;
812 EmissionDetails
.LineStarts
.clear();
815 bool JITEmitter::finishFunction(MachineFunction
&F
) {
816 if (CurBufferPtr
== BufferEnd
) {
817 // We must call endFunctionBody before retrying, because
818 // deallocateMemForFunction requires it.
819 MemMgr
->endFunctionBody(F
.getFunction(), BufferBegin
, CurBufferPtr
);
820 retryWithMoreMemory(F
);
824 if (MachineJumpTableInfo
*MJTI
= F
.getJumpTableInfo())
825 emitJumpTableInfo(MJTI
);
827 // FnStart is the start of the text, not the start of the constant pool and
828 // other per-function data.
830 (uint8_t *)TheJIT
->getPointerToGlobalIfAvailable(F
.getFunction());
832 // FnEnd is the end of the function's machine code.
833 uint8_t *FnEnd
= CurBufferPtr
;
835 if (!Relocations
.empty()) {
836 CurFn
= F
.getFunction();
837 NumRelos
+= Relocations
.size();
839 // Resolve the relocations to concrete pointers.
840 for (unsigned i
= 0, e
= Relocations
.size(); i
!= e
; ++i
) {
841 MachineRelocation
&MR
= Relocations
[i
];
843 if (!MR
.letTargetResolve()) {
844 if (MR
.isExternalSymbol()) {
845 ResultPtr
= TheJIT
->getPointerToNamedFunction(MR
.getExternalSymbol(),
847 DEBUG(dbgs() << "JIT: Map \'" << MR
.getExternalSymbol() << "\' to ["
848 << ResultPtr
<< "]\n");
850 // If the target REALLY wants a stub for this function, emit it now.
851 if (MR
.mayNeedFarStub()) {
852 ResultPtr
= Resolver
.getExternalFunctionStub(ResultPtr
);
854 } else if (MR
.isGlobalValue()) {
855 ResultPtr
= getPointerToGlobal(MR
.getGlobalValue(),
856 BufferBegin
+MR
.getMachineCodeOffset(),
857 MR
.mayNeedFarStub());
858 } else if (MR
.isIndirectSymbol()) {
859 ResultPtr
= getPointerToGVIndirectSym(
860 MR
.getGlobalValue(), BufferBegin
+MR
.getMachineCodeOffset());
861 } else if (MR
.isBasicBlock()) {
862 ResultPtr
= (void*)getMachineBasicBlockAddress(MR
.getBasicBlock());
863 } else if (MR
.isConstantPoolIndex()) {
865 (void*)getConstantPoolEntryAddress(MR
.getConstantPoolIndex());
867 assert(MR
.isJumpTableIndex());
868 ResultPtr
=(void*)getJumpTableEntryAddress(MR
.getJumpTableIndex());
871 MR
.setResultPointer(ResultPtr
);
874 // if we are managing the GOT and the relocation wants an index,
876 if (MR
.isGOTRelative() && MemMgr
->isManagingGOT()) {
877 unsigned idx
= Resolver
.getGOTIndexForAddr(ResultPtr
);
879 if (((void**)MemMgr
->getGOTBase())[idx
] != ResultPtr
) {
880 DEBUG(dbgs() << "JIT: GOT was out of date for " << ResultPtr
881 << " pointing at " << ((void**)MemMgr
->getGOTBase())[idx
]
883 ((void**)MemMgr
->getGOTBase())[idx
] = ResultPtr
;
889 TheJIT
->getJITInfo().relocate(BufferBegin
, &Relocations
[0],
890 Relocations
.size(), MemMgr
->getGOTBase());
893 // Update the GOT entry for F to point to the new code.
894 if (MemMgr
->isManagingGOT()) {
895 unsigned idx
= Resolver
.getGOTIndexForAddr((void*)BufferBegin
);
896 if (((void**)MemMgr
->getGOTBase())[idx
] != (void*)BufferBegin
) {
897 DEBUG(dbgs() << "JIT: GOT was out of date for " << (void*)BufferBegin
898 << " pointing at " << ((void**)MemMgr
->getGOTBase())[idx
]
900 ((void**)MemMgr
->getGOTBase())[idx
] = (void*)BufferBegin
;
904 // CurBufferPtr may have moved beyond FnEnd, due to memory allocation for
905 // global variables that were referenced in the relocations.
906 MemMgr
->endFunctionBody(F
.getFunction(), BufferBegin
, CurBufferPtr
);
908 if (CurBufferPtr
== BufferEnd
) {
909 retryWithMoreMemory(F
);
912 // Now that we've succeeded in emitting the function, reset the
913 // SizeEstimate back down to zero.
917 BufferBegin
= CurBufferPtr
= 0;
918 NumBytes
+= FnEnd
-FnStart
;
920 // Invalidate the icache if necessary.
921 sys::Memory::InvalidateInstructionCache(FnStart
, FnEnd
-FnStart
);
923 TheJIT
->NotifyFunctionEmitted(*F
.getFunction(), FnStart
, FnEnd
-FnStart
,
926 // Reset the previous debug location.
929 DEBUG(dbgs() << "JIT: Finished CodeGen of [" << (void*)FnStart
930 << "] Function: " << F
.getFunction()->getName()
931 << ": " << (FnEnd
-FnStart
) << " bytes of text, "
932 << Relocations
.size() << " relocations\n");
935 ConstPoolAddresses
.clear();
937 // Mark code region readable and executable if it's not so already.
938 MemMgr
->setMemoryExecutable();
941 if (sys::hasDisassembler()) {
942 dbgs() << "JIT: Disassembled code:\n";
943 dbgs() << sys::disassembleBuffer(FnStart
, FnEnd
-FnStart
,
946 dbgs() << "JIT: Binary code:\n";
947 uint8_t* q
= FnStart
;
948 for (int i
= 0; q
< FnEnd
; q
+= 4, ++i
) {
952 dbgs() << "JIT: " << (long)(q
- FnStart
) << ": ";
954 for (int j
= 3; j
>= 0; --j
) {
958 dbgs() << (unsigned short)q
[j
];
970 if (JITExceptionHandling
|| JITEmitDebugInfo
) {
971 uintptr_t ActualSize
= 0;
972 SavedBufferBegin
= BufferBegin
;
973 SavedBufferEnd
= BufferEnd
;
974 SavedCurBufferPtr
= CurBufferPtr
;
976 BufferBegin
= CurBufferPtr
= MemMgr
->startExceptionTable(F
.getFunction(),
978 BufferEnd
= BufferBegin
+ActualSize
;
979 EmittedFunctions
[F
.getFunction()].ExceptionTable
= BufferBegin
;
981 uint8_t *FrameRegister
= DE
->EmitDwarfTable(F
, *this, FnStart
, FnEnd
,
983 MemMgr
->endExceptionTable(F
.getFunction(), BufferBegin
, CurBufferPtr
,
985 uint8_t *EhEnd
= CurBufferPtr
;
986 BufferBegin
= SavedBufferBegin
;
987 BufferEnd
= SavedBufferEnd
;
988 CurBufferPtr
= SavedCurBufferPtr
;
990 if (JITExceptionHandling
) {
991 TheJIT
->RegisterTable(F
.getFunction(), FrameRegister
);
994 if (JITEmitDebugInfo
) {
1000 DR
->RegisterFunction(F
.getFunction(), I
);
1010 void JITEmitter::retryWithMoreMemory(MachineFunction
&F
) {
1011 DEBUG(dbgs() << "JIT: Ran out of space for native code. Reattempting.\n");
1012 Relocations
.clear(); // Clear the old relocations or we'll reapply them.
1013 ConstPoolAddresses
.clear();
1015 deallocateMemForFunction(F
.getFunction());
1016 // Try again with at least twice as much free space.
1017 SizeEstimate
= (uintptr_t)(2 * (BufferEnd
- BufferBegin
));
1019 for (MachineFunction::iterator MBB
= F
.begin(), E
= F
.end(); MBB
!= E
; ++MBB
){
1020 if (MBB
->hasAddressTaken())
1021 TheJIT
->clearPointerToBasicBlock(MBB
->getBasicBlock());
1025 /// deallocateMemForFunction - Deallocate all memory for the specified
1026 /// function body. Also drop any references the function has to stubs.
1027 /// May be called while the Function is being destroyed inside ~Value().
1028 void JITEmitter::deallocateMemForFunction(const Function
*F
) {
1029 ValueMap
<const Function
*, EmittedCode
, EmittedFunctionConfig
>::iterator
1030 Emitted
= EmittedFunctions
.find(F
);
1031 if (Emitted
!= EmittedFunctions
.end()) {
1032 MemMgr
->deallocateFunctionBody(Emitted
->second
.FunctionBody
);
1033 MemMgr
->deallocateExceptionTable(Emitted
->second
.ExceptionTable
);
1034 TheJIT
->NotifyFreeingMachineCode(Emitted
->second
.Code
);
1036 EmittedFunctions
.erase(Emitted
);
1039 if(JITExceptionHandling
) {
1040 TheJIT
->DeregisterTable(F
);
1043 if (JITEmitDebugInfo
) {
1044 DR
->UnregisterFunction(F
);
1049 void* JITEmitter::allocateSpace(uintptr_t Size
, unsigned Alignment
) {
1051 return JITCodeEmitter::allocateSpace(Size
, Alignment
);
1053 // create a new memory block if there is no active one.
1054 // care must be taken so that BufferBegin is invalidated when a
1056 BufferBegin
= CurBufferPtr
= MemMgr
->allocateSpace(Size
, Alignment
);
1057 BufferEnd
= BufferBegin
+Size
;
1058 return CurBufferPtr
;
1061 void* JITEmitter::allocateGlobal(uintptr_t Size
, unsigned Alignment
) {
1062 // Delegate this call through the memory manager.
1063 return MemMgr
->allocateGlobal(Size
, Alignment
);
1066 void JITEmitter::emitConstantPool(MachineConstantPool
*MCP
) {
1067 if (TheJIT
->getJITInfo().hasCustomConstantPool())
1070 const std::vector
<MachineConstantPoolEntry
> &Constants
= MCP
->getConstants();
1071 if (Constants
.empty()) return;
1073 unsigned Size
= GetConstantPoolSizeInBytes(MCP
, TheJIT
->getTargetData());
1074 unsigned Align
= MCP
->getConstantPoolAlignment();
1075 ConstantPoolBase
= allocateSpace(Size
, Align
);
1078 if (ConstantPoolBase
== 0) return; // Buffer overflow.
1080 DEBUG(dbgs() << "JIT: Emitted constant pool at [" << ConstantPoolBase
1081 << "] (size: " << Size
<< ", alignment: " << Align
<< ")\n");
1083 // Initialize the memory for all of the constant pool entries.
1084 unsigned Offset
= 0;
1085 for (unsigned i
= 0, e
= Constants
.size(); i
!= e
; ++i
) {
1086 MachineConstantPoolEntry CPE
= Constants
[i
];
1087 unsigned AlignMask
= CPE
.getAlignment() - 1;
1088 Offset
= (Offset
+ AlignMask
) & ~AlignMask
;
1090 uintptr_t CAddr
= (uintptr_t)ConstantPoolBase
+ Offset
;
1091 ConstPoolAddresses
.push_back(CAddr
);
1092 if (CPE
.isMachineConstantPoolEntry()) {
1093 // FIXME: add support to lower machine constant pool values into bytes!
1094 report_fatal_error("Initialize memory with machine specific constant pool"
1095 "entry has not been implemented!");
1097 TheJIT
->InitializeMemory(CPE
.Val
.ConstVal
, (void*)CAddr
);
1098 DEBUG(dbgs() << "JIT: CP" << i
<< " at [0x";
1099 dbgs().write_hex(CAddr
) << "]\n");
1101 const Type
*Ty
= CPE
.Val
.ConstVal
->getType();
1102 Offset
+= TheJIT
->getTargetData()->getTypeAllocSize(Ty
);
1106 void JITEmitter::initJumpTableInfo(MachineJumpTableInfo
*MJTI
) {
1107 if (TheJIT
->getJITInfo().hasCustomJumpTables())
1109 if (MJTI
->getEntryKind() == MachineJumpTableInfo::EK_Inline
)
1112 const std::vector
<MachineJumpTableEntry
> &JT
= MJTI
->getJumpTables();
1113 if (JT
.empty()) return;
1115 unsigned NumEntries
= 0;
1116 for (unsigned i
= 0, e
= JT
.size(); i
!= e
; ++i
)
1117 NumEntries
+= JT
[i
].MBBs
.size();
1119 unsigned EntrySize
= MJTI
->getEntrySize(*TheJIT
->getTargetData());
1121 // Just allocate space for all the jump tables now. We will fix up the actual
1122 // MBB entries in the tables after we emit the code for each block, since then
1123 // we will know the final locations of the MBBs in memory.
1125 JumpTableBase
= allocateSpace(NumEntries
* EntrySize
,
1126 MJTI
->getEntryAlignment(*TheJIT
->getTargetData()));
1129 void JITEmitter::emitJumpTableInfo(MachineJumpTableInfo
*MJTI
) {
1130 if (TheJIT
->getJITInfo().hasCustomJumpTables())
1133 const std::vector
<MachineJumpTableEntry
> &JT
= MJTI
->getJumpTables();
1134 if (JT
.empty() || JumpTableBase
== 0) return;
1137 switch (MJTI
->getEntryKind()) {
1138 case MachineJumpTableInfo::EK_Inline
:
1140 case MachineJumpTableInfo::EK_BlockAddress
: {
1141 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1143 assert(MJTI
->getEntrySize(*TheJIT
->getTargetData()) == sizeof(void*) &&
1146 // For each jump table, map each target in the jump table to the address of
1147 // an emitted MachineBasicBlock.
1148 intptr_t *SlotPtr
= (intptr_t*)JumpTableBase
;
1150 for (unsigned i
= 0, e
= JT
.size(); i
!= e
; ++i
) {
1151 const std::vector
<MachineBasicBlock
*> &MBBs
= JT
[i
].MBBs
;
1152 // Store the address of the basic block for this jump table slot in the
1153 // memory we allocated for the jump table in 'initJumpTableInfo'
1154 for (unsigned mi
= 0, me
= MBBs
.size(); mi
!= me
; ++mi
)
1155 *SlotPtr
++ = getMachineBasicBlockAddress(MBBs
[mi
]);
1160 case MachineJumpTableInfo::EK_Custom32
:
1161 case MachineJumpTableInfo::EK_GPRel32BlockAddress
:
1162 case MachineJumpTableInfo::EK_LabelDifference32
: {
1163 assert(MJTI
->getEntrySize(*TheJIT
->getTargetData()) == 4&&"Cross JIT'ing?");
1164 // For each jump table, place the offset from the beginning of the table
1165 // to the target address.
1166 int *SlotPtr
= (int*)JumpTableBase
;
1168 for (unsigned i
= 0, e
= JT
.size(); i
!= e
; ++i
) {
1169 const std::vector
<MachineBasicBlock
*> &MBBs
= JT
[i
].MBBs
;
1170 // Store the offset of the basic block for this jump table slot in the
1171 // memory we allocated for the jump table in 'initJumpTableInfo'
1172 uintptr_t Base
= (uintptr_t)SlotPtr
;
1173 for (unsigned mi
= 0, me
= MBBs
.size(); mi
!= me
; ++mi
) {
1174 uintptr_t MBBAddr
= getMachineBasicBlockAddress(MBBs
[mi
]);
1175 /// FIXME: USe EntryKind instead of magic "getPICJumpTableEntry" hook.
1176 *SlotPtr
++ = TheJIT
->getJITInfo().getPICJumpTableEntry(MBBAddr
, Base
);
1184 void JITEmitter::startGVStub(const GlobalValue
* GV
,
1185 unsigned StubSize
, unsigned Alignment
) {
1186 SavedBufferBegin
= BufferBegin
;
1187 SavedBufferEnd
= BufferEnd
;
1188 SavedCurBufferPtr
= CurBufferPtr
;
1190 BufferBegin
= CurBufferPtr
= MemMgr
->allocateStub(GV
, StubSize
, Alignment
);
1191 BufferEnd
= BufferBegin
+StubSize
+1;
1194 void JITEmitter::startGVStub(void *Buffer
, unsigned StubSize
) {
1195 SavedBufferBegin
= BufferBegin
;
1196 SavedBufferEnd
= BufferEnd
;
1197 SavedCurBufferPtr
= CurBufferPtr
;
1199 BufferBegin
= CurBufferPtr
= (uint8_t *)Buffer
;
1200 BufferEnd
= BufferBegin
+StubSize
+1;
1203 void JITEmitter::finishGVStub() {
1204 assert(CurBufferPtr
!= BufferEnd
&& "Stub overflowed allocated space.");
1205 NumBytes
+= getCurrentPCOffset();
1206 BufferBegin
= SavedBufferBegin
;
1207 BufferEnd
= SavedBufferEnd
;
1208 CurBufferPtr
= SavedCurBufferPtr
;
1211 void *JITEmitter::allocIndirectGV(const GlobalValue
*GV
,
1212 const uint8_t *Buffer
, size_t Size
,
1213 unsigned Alignment
) {
1214 uint8_t *IndGV
= MemMgr
->allocateStub(GV
, Size
, Alignment
);
1215 memcpy(IndGV
, Buffer
, Size
);
1219 // getConstantPoolEntryAddress - Return the address of the 'ConstantNum' entry
1220 // in the constant pool that was last emitted with the 'emitConstantPool'
1223 uintptr_t JITEmitter::getConstantPoolEntryAddress(unsigned ConstantNum
) const {
1224 assert(ConstantNum
< ConstantPool
->getConstants().size() &&
1225 "Invalid ConstantPoolIndex!");
1226 return ConstPoolAddresses
[ConstantNum
];
1229 // getJumpTableEntryAddress - Return the address of the JumpTable with index
1230 // 'Index' in the jumpp table that was last initialized with 'initJumpTableInfo'
1232 uintptr_t JITEmitter::getJumpTableEntryAddress(unsigned Index
) const {
1233 const std::vector
<MachineJumpTableEntry
> &JT
= JumpTable
->getJumpTables();
1234 assert(Index
< JT
.size() && "Invalid jump table index!");
1236 unsigned EntrySize
= JumpTable
->getEntrySize(*TheJIT
->getTargetData());
1238 unsigned Offset
= 0;
1239 for (unsigned i
= 0; i
< Index
; ++i
)
1240 Offset
+= JT
[i
].MBBs
.size();
1242 Offset
*= EntrySize
;
1244 return (uintptr_t)((char *)JumpTableBase
+ Offset
);
1247 void JITEmitter::EmittedFunctionConfig::onDelete(
1248 JITEmitter
*Emitter
, const Function
*F
) {
1249 Emitter
->deallocateMemForFunction(F
);
1251 void JITEmitter::EmittedFunctionConfig::onRAUW(
1252 JITEmitter
*, const Function
*, const Function
*) {
1253 llvm_unreachable("The JIT doesn't know how to handle a"
1254 " RAUW on a value it has emitted.");
1258 //===----------------------------------------------------------------------===//
1259 // Public interface to this file
1260 //===----------------------------------------------------------------------===//
1262 JITCodeEmitter
*JIT::createEmitter(JIT
&jit
, JITMemoryManager
*JMM
,
1263 TargetMachine
&tm
) {
1264 return new JITEmitter(jit
, JMM
, tm
);
1267 // getPointerToFunctionOrStub - If the specified function has been
1268 // code-gen'd, return a pointer to the function. If not, compile it, or use
1269 // a stub to implement lazy compilation if available.
1271 void *JIT::getPointerToFunctionOrStub(Function
*F
) {
1272 // If we have already code generated the function, just return the address.
1273 if (void *Addr
= getPointerToGlobalIfAvailable(F
))
1276 // Get a stub if the target supports it.
1277 assert(isa
<JITEmitter
>(JCE
) && "Unexpected MCE?");
1278 JITEmitter
*JE
= cast
<JITEmitter
>(getCodeEmitter());
1279 return JE
->getJITResolver().getLazyFunctionStub(F
);
1282 void JIT::updateFunctionStub(Function
*F
) {
1283 // Get the empty stub we generated earlier.
1284 assert(isa
<JITEmitter
>(JCE
) && "Unexpected MCE?");
1285 JITEmitter
*JE
= cast
<JITEmitter
>(getCodeEmitter());
1286 void *Stub
= JE
->getJITResolver().getLazyFunctionStub(F
);
1287 void *Addr
= getPointerToGlobalIfAvailable(F
);
1288 assert(Addr
!= Stub
&& "Function must have non-stub address to be updated.");
1290 // Tell the target jit info to rewrite the stub at the specified address,
1291 // rather than creating a new one.
1292 TargetJITInfo::StubLayout layout
= getJITInfo().getStubLayout();
1293 JE
->startGVStub(Stub
, layout
.Size
);
1294 getJITInfo().emitFunctionStub(F
, Addr
, *getCodeEmitter());
1298 /// freeMachineCodeForFunction - release machine code memory for given Function.
1300 void JIT::freeMachineCodeForFunction(Function
*F
) {
1301 // Delete translation for this from the ExecutionEngine, so it will get
1302 // retranslated next time it is used.
1303 updateGlobalMapping(F
, 0);
1305 // Free the actual memory for the function body and related stuff.
1306 assert(isa
<JITEmitter
>(JCE
) && "Unexpected MCE?");
1307 cast
<JITEmitter
>(JCE
)->deallocateMemForFunction(F
);