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Chris Lattnerbd199fb2002-12-24 00:01:05 +00001//===-- Emitter.cpp - Write machine code to executable memory -------------===//
John Criswellb576c942003-10-20 19:43:21 +00002//
3// The LLVM Compiler Infrastructure
4//
5// This file was developed by the LLVM research group and is distributed under
6// the University of Illinois Open Source License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
Chris Lattnerbd199fb2002-12-24 00:01:05 +00009//
Chris Lattner5be478f2004-11-20 03:46:14 +000010// 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.
Chris Lattnerbd199fb2002-12-24 00:01:05 +000012//
13//===----------------------------------------------------------------------===//
14
Chris Lattner3785fad2003-08-05 17:00:32 +000015#define DEBUG_TYPE "jit"
Chris Lattner4d326fa2003-12-20 01:46:27 +000016#include "JIT.h"
Chris Lattner2c0a6a12003-11-30 04:23:21 +000017#include "llvm/Constant.h"
18#include "llvm/Module.h"
Chris Lattnerbd199fb2002-12-24 00:01:05 +000019#include "llvm/CodeGen/MachineCodeEmitter.h"
20#include "llvm/CodeGen/MachineFunction.h"
Chris Lattner1cc08382003-01-13 01:00:12 +000021#include "llvm/CodeGen/MachineConstantPool.h"
Chris Lattner5be478f2004-11-20 03:46:14 +000022#include "llvm/CodeGen/MachineRelocation.h"
Chris Lattner1cc08382003-01-13 01:00:12 +000023#include "llvm/Target/TargetData.h"
Chris Lattner5be478f2004-11-20 03:46:14 +000024#include "llvm/Target/TargetJITInfo.h"
Reid Spencer551ccae2004-09-01 22:55:40 +000025#include "llvm/Support/Debug.h"
26#include "llvm/ADT/Statistic.h"
Reid Spencer52b0ba62004-09-11 04:31:03 +000027#include "llvm/System/Memory.h"
Chris Lattnerc19aade2003-12-08 08:06:28 +000028using namespace llvm;
Brian Gaeked0fde302003-11-11 22:41:34 +000029
Chris Lattnerbd199fb2002-12-24 00:01:05 +000030namespace {
Chris Lattnere7386562003-10-20 05:45:49 +000031 Statistic<> NumBytes("jit", "Number of bytes of machine code compiled");
Chris Lattner4d326fa2003-12-20 01:46:27 +000032 JIT *TheJIT = 0;
Chris Lattner54266522004-11-20 23:57:07 +000033}
Chris Lattnerbd199fb2002-12-24 00:01:05 +000034
Chris Lattner54266522004-11-20 23:57:07 +000035
36//===----------------------------------------------------------------------===//
37// JITMemoryManager code.
38//
39namespace {
Chris Lattner688506d2003-08-14 18:35:27 +000040 /// JITMemoryManager - Manage memory for the JIT code generation in a logical,
41 /// sane way. This splits a large block of MAP_NORESERVE'd memory into two
42 /// sections, one for function stubs, one for the functions themselves. We
43 /// have to do this because we may need to emit a function stub while in the
44 /// middle of emitting a function, and we don't know how large the function we
45 /// are emitting is. This never bothers to release the memory, because when
46 /// we are ready to destroy the JIT, the program exits.
47 class JITMemoryManager {
Reid Spencer33189e72004-09-13 22:38:11 +000048 sys::MemoryBlock MemBlock; // Virtual memory block allocated RWX
Chris Lattner688506d2003-08-14 18:35:27 +000049 unsigned char *MemBase; // Base of block of memory, start of stub mem
50 unsigned char *FunctionBase; // Start of the function body area
51 unsigned char *CurStubPtr, *CurFunctionPtr;
52 public:
53 JITMemoryManager();
54
55 inline unsigned char *allocateStub(unsigned StubSize);
56 inline unsigned char *startFunctionBody();
57 inline void endFunctionBody(unsigned char *FunctionEnd);
58 };
59}
60
Chris Lattner688506d2003-08-14 18:35:27 +000061JITMemoryManager::JITMemoryManager() {
62 // Allocate a 16M block of memory...
Reid Spencer33189e72004-09-13 22:38:11 +000063 MemBlock = sys::Memory::AllocateRWX((16 << 20));
Reid Spencer52b0ba62004-09-11 04:31:03 +000064 MemBase = reinterpret_cast<unsigned char*>(MemBlock.base());
Chris Lattner688506d2003-08-14 18:35:27 +000065 FunctionBase = MemBase + 512*1024; // Use 512k for stubs
66
67 // Allocate stubs backwards from the function base, allocate functions forward
68 // from the function base.
69 CurStubPtr = CurFunctionPtr = FunctionBase;
70}
71
72unsigned char *JITMemoryManager::allocateStub(unsigned StubSize) {
73 CurStubPtr -= StubSize;
74 if (CurStubPtr < MemBase) {
75 std::cerr << "JIT ran out of memory for function stubs!\n";
76 abort();
77 }
78 return CurStubPtr;
79}
80
81unsigned char *JITMemoryManager::startFunctionBody() {
Chris Lattner5be478f2004-11-20 03:46:14 +000082 // Round up to an even multiple of 8 bytes, this should eventually be target
Chris Lattner688506d2003-08-14 18:35:27 +000083 // specific.
Chris Lattner5be478f2004-11-20 03:46:14 +000084 return (unsigned char*)(((intptr_t)CurFunctionPtr + 7) & ~7);
Chris Lattner688506d2003-08-14 18:35:27 +000085}
86
87void JITMemoryManager::endFunctionBody(unsigned char *FunctionEnd) {
88 assert(FunctionEnd > CurFunctionPtr);
89 CurFunctionPtr = FunctionEnd;
90}
91
Chris Lattner54266522004-11-20 23:57:07 +000092//===----------------------------------------------------------------------===//
93// JIT lazy compilation code.
94//
95namespace {
96 /// JITResolver - Keep track of, and resolve, call sites for functions that
97 /// have not yet been compiled.
98 class JITResolver {
Chris Lattner5e225582004-11-21 03:37:42 +000099 /// MCE - The MachineCodeEmitter to use to emit stubs with.
Chris Lattner54266522004-11-20 23:57:07 +0000100 MachineCodeEmitter &MCE;
101
Chris Lattner5e225582004-11-21 03:37:42 +0000102 /// LazyResolverFn - The target lazy resolver function that we actually
103 /// rewrite instructions to use.
104 TargetJITInfo::LazyResolverFn LazyResolverFn;
105
Chris Lattner54266522004-11-20 23:57:07 +0000106 // FunctionToStubMap - Keep track of the stub created for a particular
107 // function so that we can reuse them if necessary.
108 std::map<Function*, void*> FunctionToStubMap;
109
110 // StubToFunctionMap - Keep track of the function that each stub corresponds
111 // to.
112 std::map<void*, Function*> StubToFunctionMap;
113
114 public:
Chris Lattner5e225582004-11-21 03:37:42 +0000115 JITResolver(MachineCodeEmitter &mce) : MCE(mce) {
116 LazyResolverFn =
117 TheJIT->getJITInfo().getLazyResolverFunction(JITCompilerFn);
118 }
Chris Lattner54266522004-11-20 23:57:07 +0000119
120 /// getFunctionStub - This returns a pointer to a function stub, creating
121 /// one on demand as needed.
122 void *getFunctionStub(Function *F);
123
Chris Lattner5e225582004-11-21 03:37:42 +0000124 /// AddCallbackAtLocation - If the target is capable of rewriting an
125 /// instruction without the use of a stub, record the location of the use so
126 /// we know which function is being used at the location.
127 void *AddCallbackAtLocation(Function *F, void *Location) {
128 /// Get the target-specific JIT resolver function.
129 StubToFunctionMap[Location] = F;
130 return (void*)LazyResolverFn;
131 }
132
Chris Lattner54266522004-11-20 23:57:07 +0000133 /// JITCompilerFn - This function is called to resolve a stub to a compiled
134 /// address. If the LLVM Function corresponding to the stub has not yet
135 /// been compiled, this function compiles it first.
136 static void *JITCompilerFn(void *Stub);
137 };
138}
139
140/// getJITResolver - This function returns the one instance of the JIT resolver.
141///
142static JITResolver &getJITResolver(MachineCodeEmitter *MCE = 0) {
143 static JITResolver TheJITResolver(*MCE);
144 return TheJITResolver;
145}
146
147/// getFunctionStub - This returns a pointer to a function stub, creating
148/// one on demand as needed.
149void *JITResolver::getFunctionStub(Function *F) {
Chris Lattner54266522004-11-20 23:57:07 +0000150 // If we already have a stub for this function, recycle it.
151 void *&Stub = FunctionToStubMap[F];
152 if (Stub) return Stub;
153
Chris Lattnerb43dbdc2004-11-22 07:24:43 +0000154 // Call the lazy resolver function unless we already KNOW it is an external
155 // function, in which case we just skip the lazy resolution step.
156 void *Actual = (void*)LazyResolverFn;
157 if (F->hasExternalLinkage())
158 Actual = TheJIT->getPointerToFunction(F);
159
Chris Lattner54266522004-11-20 23:57:07 +0000160 // Otherwise, codegen a new stub. For now, the stub will call the lazy
161 // resolver function.
Chris Lattnerb43dbdc2004-11-22 07:24:43 +0000162 Stub = TheJIT->getJITInfo().emitFunctionStub(Actual, MCE);
163
164 if (F->hasExternalLinkage()) {
165 // If we are getting the stub for an external function, we really want the
166 // address of the stub in the GlobalAddressMap for the JIT, not the address
167 // of the external function.
168 TheJIT->updateGlobalMapping(F, Stub);
169 }
Chris Lattner54266522004-11-20 23:57:07 +0000170
Chris Lattnercb479412004-11-21 03:44:32 +0000171 DEBUG(std::cerr << "JIT: Stub emitted at [" << Stub << "] for function '"
Chris Lattner6f717202004-11-22 21:48:33 +0000172 << F->getName() << "'\n");
Chris Lattnercb479412004-11-21 03:44:32 +0000173
Chris Lattner54266522004-11-20 23:57:07 +0000174 // Finally, keep track of the stub-to-Function mapping so that the
175 // JITCompilerFn knows which function to compile!
176 StubToFunctionMap[Stub] = F;
177 return Stub;
178}
179
180/// JITCompilerFn - This function is called when a lazy compilation stub has
181/// been entered. It looks up which function this stub corresponds to, compiles
182/// it if necessary, then returns the resultant function pointer.
183void *JITResolver::JITCompilerFn(void *Stub) {
184 JITResolver &JR = getJITResolver();
185
186 // The address given to us for the stub may not be exactly right, it might be
187 // a little bit after the stub. As such, use upper_bound to find it.
188 std::map<void*, Function*>::iterator I =
189 JR.StubToFunctionMap.upper_bound(Stub);
190 assert(I != JR.StubToFunctionMap.begin() && "This is not a known stub!");
191 Function *F = (--I)->second;
192
193 // The target function will rewrite the stub so that the compilation callback
194 // function is no longer called from this stub.
195 JR.StubToFunctionMap.erase(I);
196
Chris Lattnercb479412004-11-21 03:44:32 +0000197 DEBUG(std::cerr << "JIT: Lazily resolving function '" << F->getName()
Chris Lattner54266522004-11-20 23:57:07 +0000198 << "' In stub ptr = " << Stub << " actual ptr = "
199 << I->first << "\n");
200
201 void *Result = TheJIT->getPointerToFunction(F);
202
203 // We don't need to reuse this stub in the future, as F is now compiled.
204 JR.FunctionToStubMap.erase(F);
205
206 // FIXME: We could rewrite all references to this stub if we knew them.
207 return Result;
208}
Chris Lattner688506d2003-08-14 18:35:27 +0000209
210
Chris Lattner54266522004-11-20 23:57:07 +0000211//===----------------------------------------------------------------------===//
212// JIT MachineCodeEmitter code.
213//
Chris Lattner688506d2003-08-14 18:35:27 +0000214namespace {
Brian Gaeke6020ddd2003-10-16 23:33:38 +0000215 /// Emitter - The JIT implementation of the MachineCodeEmitter, which is used
Chris Lattner688506d2003-08-14 18:35:27 +0000216 /// to output functions to memory for execution.
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000217 class Emitter : public MachineCodeEmitter {
Chris Lattner688506d2003-08-14 18:35:27 +0000218 JITMemoryManager MemMgr;
219
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000220 // CurBlock - The start of the current block of memory. CurByte - The
221 // current byte being emitted to.
Chris Lattner6125fdd2003-05-09 03:30:07 +0000222 unsigned char *CurBlock, *CurByte;
223
224 // When outputting a function stub in the context of some other function, we
225 // save CurBlock and CurByte here.
226 unsigned char *SavedCurBlock, *SavedCurByte;
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000227
228 // ConstantPoolAddresses - Contains the location for each entry in the
229 // constant pool.
Chris Lattner1cc08382003-01-13 01:00:12 +0000230 std::vector<void*> ConstantPoolAddresses;
Chris Lattner5be478f2004-11-20 03:46:14 +0000231
232 /// Relocations - These are the relocations that the function needs, as
233 /// emitted.
234 std::vector<MachineRelocation> Relocations;
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000235 public:
Chris Lattner4d326fa2003-12-20 01:46:27 +0000236 Emitter(JIT &jit) { TheJIT = &jit; }
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000237
238 virtual void startFunction(MachineFunction &F);
239 virtual void finishFunction(MachineFunction &F);
Chris Lattner1cc08382003-01-13 01:00:12 +0000240 virtual void emitConstantPool(MachineConstantPool *MCP);
Chris Lattner54266522004-11-20 23:57:07 +0000241 virtual void startFunctionStub(unsigned StubSize);
242 virtual void* finishFunctionStub(const Function *F);
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000243 virtual void emitByte(unsigned char B);
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000244 virtual void emitWord(unsigned W);
Brian Gaekeaea1b582004-04-23 17:11:14 +0000245 virtual void emitWordAt(unsigned W, unsigned *Ptr);
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000246
Chris Lattner5be478f2004-11-20 03:46:14 +0000247 virtual void addRelocation(const MachineRelocation &MR) {
248 Relocations.push_back(MR);
249 }
250
251 virtual uint64_t getCurrentPCValue();
252 virtual uint64_t getCurrentPCOffset();
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000253 virtual uint64_t getConstantPoolEntryAddress(unsigned Entry);
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000254
255 // forceCompilationOf - Force the compilation of the specified function, and
256 // return its address, because we REALLY need the address now.
257 //
258 // FIXME: This is JIT specific!
259 //
260 virtual uint64_t forceCompilationOf(Function *F);
Chris Lattner54266522004-11-20 23:57:07 +0000261
262 private:
Chris Lattner5e225582004-11-21 03:37:42 +0000263 void *getPointerToGlobal(GlobalValue *GV, void *Reference, bool NoNeedStub);
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000264 };
265}
266
Chris Lattner4d326fa2003-12-20 01:46:27 +0000267MachineCodeEmitter *JIT::createEmitter(JIT &jit) {
268 return new Emitter(jit);
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000269}
270
Chris Lattner5e225582004-11-21 03:37:42 +0000271void *Emitter::getPointerToGlobal(GlobalValue *V, void *Reference,
272 bool DoesntNeedStub) {
Chris Lattner54266522004-11-20 23:57:07 +0000273 if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
274 /// FIXME: If we straightened things out, this could actually emit the
275 /// global immediately instead of queuing it for codegen later!
276 GlobalVariable *GV = cast<GlobalVariable>(V);
277 return TheJIT->getOrEmitGlobalVariable(GV);
278 }
279
280 // If we have already compiled the function, return a pointer to its body.
281 Function *F = cast<Function>(V);
282 void *ResultPtr = TheJIT->getPointerToGlobalIfAvailable(F);
283 if (ResultPtr) return ResultPtr;
284
285 if (F->hasExternalLinkage()) {
286 // If this is an external function pointer, we can force the JIT to
287 // 'compile' it, which really just adds it to the map.
Chris Lattnerb43dbdc2004-11-22 07:24:43 +0000288 if (DoesntNeedStub)
289 return TheJIT->getPointerToFunction(F);
290
291 return getJITResolver(this).getFunctionStub(F);
Chris Lattner54266522004-11-20 23:57:07 +0000292 }
293
Chris Lattner5e225582004-11-21 03:37:42 +0000294 // Okay, the function has not been compiled yet, if the target callback
295 // mechanism is capable of rewriting the instruction directly, prefer to do
296 // that instead of emitting a stub.
297 if (DoesntNeedStub)
298 return getJITResolver(this).AddCallbackAtLocation(F, Reference);
299
Chris Lattner54266522004-11-20 23:57:07 +0000300 // Otherwise, we have to emit a lazy resolving stub.
301 return getJITResolver(this).getFunctionStub(F);
302}
303
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000304void Emitter::startFunction(MachineFunction &F) {
Chris Lattner688506d2003-08-14 18:35:27 +0000305 CurByte = CurBlock = MemMgr.startFunctionBody();
Chris Lattner4d326fa2003-12-20 01:46:27 +0000306 TheJIT->addGlobalMapping(F.getFunction(), CurBlock);
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000307}
308
309void Emitter::finishFunction(MachineFunction &F) {
Chris Lattner688506d2003-08-14 18:35:27 +0000310 MemMgr.endFunctionBody(CurByte);
Chris Lattner1cc08382003-01-13 01:00:12 +0000311 ConstantPoolAddresses.clear();
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000312 NumBytes += CurByte-CurBlock;
313
Chris Lattner5be478f2004-11-20 03:46:14 +0000314 if (!Relocations.empty()) {
315 // Resolve the relocations to concrete pointers.
316 for (unsigned i = 0, e = Relocations.size(); i != e; ++i) {
317 MachineRelocation &MR = Relocations[i];
318 void *ResultPtr;
Chris Lattner54266522004-11-20 23:57:07 +0000319 if (MR.isString())
Chris Lattner5be478f2004-11-20 03:46:14 +0000320 ResultPtr = TheJIT->getPointerToNamedFunction(MR.getString());
Chris Lattner54266522004-11-20 23:57:07 +0000321 else
Chris Lattner5e225582004-11-21 03:37:42 +0000322 ResultPtr = getPointerToGlobal(MR.getGlobalValue(),
323 CurBlock+MR.getMachineCodeOffset(),
324 MR.doesntNeedFunctionStub());
Chris Lattner5be478f2004-11-20 03:46:14 +0000325 MR.setResultPointer(ResultPtr);
326 }
327
328 TheJIT->getJITInfo().relocate(CurBlock, &Relocations[0],
329 Relocations.size());
330 }
331
Chris Lattnercb479412004-11-21 03:44:32 +0000332 DEBUG(std::cerr << "JIT: Finished CodeGen of [" << (void*)CurBlock
Misha Brukman1d440852003-06-06 06:52:35 +0000333 << "] Function: " << F.getFunction()->getName()
Chris Lattner5be478f2004-11-20 03:46:14 +0000334 << ": " << CurByte-CurBlock << " bytes of text, "
335 << Relocations.size() << " relocations\n");
336 Relocations.clear();
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000337}
338
Chris Lattner1cc08382003-01-13 01:00:12 +0000339void Emitter::emitConstantPool(MachineConstantPool *MCP) {
340 const std::vector<Constant*> &Constants = MCP->getConstants();
Chris Lattner2c0a6a12003-11-30 04:23:21 +0000341 if (Constants.empty()) return;
342
343 std::vector<unsigned> ConstantOffset;
344 ConstantOffset.reserve(Constants.size());
345
346 // Calculate how much space we will need for all the constants, and the offset
347 // each one will live in.
348 unsigned TotalSize = 0;
Chris Lattner1cc08382003-01-13 01:00:12 +0000349 for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
Chris Lattner2c0a6a12003-11-30 04:23:21 +0000350 const Type *Ty = Constants[i]->getType();
Chris Lattner4d326fa2003-12-20 01:46:27 +0000351 unsigned Size = TheJIT->getTargetData().getTypeSize(Ty);
352 unsigned Alignment = TheJIT->getTargetData().getTypeAlignment(Ty);
Chris Lattner2c0a6a12003-11-30 04:23:21 +0000353 // Make sure to take into account the alignment requirements of the type.
354 TotalSize = (TotalSize + Alignment-1) & ~(Alignment-1);
355
356 // Remember the offset this element lives at.
357 ConstantOffset.push_back(TotalSize);
358 TotalSize += Size; // Reserve space for the constant.
359 }
360
361 // Now that we know how much memory to allocate, do so.
362 char *Pool = new char[TotalSize];
363
364 // Actually output all of the constants, and remember their addresses.
365 for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
366 void *Addr = Pool + ConstantOffset[i];
Chris Lattner4d326fa2003-12-20 01:46:27 +0000367 TheJIT->InitializeMemory(Constants[i], Addr);
Misha Brukman91de3522003-11-30 00:50:53 +0000368 ConstantPoolAddresses.push_back(Addr);
Chris Lattner1cc08382003-01-13 01:00:12 +0000369 }
370}
371
Chris Lattner54266522004-11-20 23:57:07 +0000372void Emitter::startFunctionStub(unsigned StubSize) {
Chris Lattner6125fdd2003-05-09 03:30:07 +0000373 SavedCurBlock = CurBlock; SavedCurByte = CurByte;
Chris Lattner688506d2003-08-14 18:35:27 +0000374 CurByte = CurBlock = MemMgr.allocateStub(StubSize);
Chris Lattner6125fdd2003-05-09 03:30:07 +0000375}
376
Chris Lattner54266522004-11-20 23:57:07 +0000377void *Emitter::finishFunctionStub(const Function *F) {
Chris Lattner6125fdd2003-05-09 03:30:07 +0000378 NumBytes += CurByte-CurBlock;
Chris Lattner6125fdd2003-05-09 03:30:07 +0000379 std::swap(CurBlock, SavedCurBlock);
380 CurByte = SavedCurByte;
381 return SavedCurBlock;
382}
383
Chris Lattnerbd199fb2002-12-24 00:01:05 +0000384void Emitter::emitByte(unsigned char B) {
385 *CurByte++ = B; // Write the byte to memory
386}
387
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000388void Emitter::emitWord(unsigned W) {
Chris Lattner688506d2003-08-14 18:35:27 +0000389 // This won't work if the endianness of the host and target don't agree! (For
390 // a JIT this can't happen though. :)
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000391 *(unsigned*)CurByte = W;
392 CurByte += sizeof(unsigned);
393}
394
Brian Gaekeaea1b582004-04-23 17:11:14 +0000395void Emitter::emitWordAt(unsigned W, unsigned *Ptr) {
396 *Ptr = W;
397}
398
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000399// getConstantPoolEntryAddress - Return the address of the 'ConstantNum' entry
400// in the constant pool that was last emitted with the 'emitConstantPool'
401// method.
402//
403uint64_t Emitter::getConstantPoolEntryAddress(unsigned ConstantNum) {
404 assert(ConstantNum < ConstantPoolAddresses.size() &&
405 "Invalid ConstantPoolIndex!");
406 return (intptr_t)ConstantPoolAddresses[ConstantNum];
407}
408
409// getCurrentPCValue - This returns the address that the next emitted byte
410// will be output to.
411//
412uint64_t Emitter::getCurrentPCValue() {
413 return (intptr_t)CurByte;
414}
415
Chris Lattner5be478f2004-11-20 03:46:14 +0000416uint64_t Emitter::getCurrentPCOffset() {
417 return (intptr_t)CurByte-(intptr_t)CurBlock;
418}
419
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000420uint64_t Emitter::forceCompilationOf(Function *F) {
Chris Lattner4d326fa2003-12-20 01:46:27 +0000421 return (intptr_t)TheJIT->getPointerToFunction(F);
Chris Lattnerbba1b6d2003-06-01 23:24:36 +0000422}
423
Misha Brukmand69c1e62003-07-28 19:09:06 +0000424// getPointerToNamedFunction - This function is used as a global wrapper to
Chris Lattner4d326fa2003-12-20 01:46:27 +0000425// JIT::getPointerToNamedFunction for the purpose of resolving symbols when
Misha Brukmand69c1e62003-07-28 19:09:06 +0000426// bugpoint is debugging the JIT. In that scenario, we are loading an .so and
427// need to resolve function(s) that are being mis-codegenerated, so we need to
428// resolve their addresses at runtime, and this is the way to do it.
429extern "C" {
430 void *getPointerToNamedFunction(const char *Name) {
Chris Lattner4d326fa2003-12-20 01:46:27 +0000431 Module &M = TheJIT->getModule();
Misha Brukmand69c1e62003-07-28 19:09:06 +0000432 if (Function *F = M.getNamedFunction(Name))
Chris Lattner4d326fa2003-12-20 01:46:27 +0000433 return TheJIT->getPointerToFunction(F);
434 return TheJIT->getPointerToNamedFunction(Name);
Misha Brukmand69c1e62003-07-28 19:09:06 +0000435 }
436}