-//===-- Emitter.cpp - Write machine code to executable memory -------------===//
-//
+//===-- JITEmitter.cpp - Write machine code to executable memory ----------===//
+//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
//===----------------------------------------------------------------------===//
//
-// This file defines a MachineCodeEmitter object that is used by Jello to write
-// machine code to memory and remember where relocatable values lie.
+// This file defines a MachineCodeEmitter object that is used by the JIT to
+// write machine code to memory and remember where relocatable values are.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "jit"
-#ifndef _POSIX_MAPPED_FILES
-#define _POSIX_MAPPED_FILES
-#endif
#include "JIT.h"
-#include "llvm/Constant.h"
+#include "JITDebugRegisterer.h"
+#include "JITDwarfEmitter.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/Constants.h"
#include "llvm/Module.h"
-#include "llvm/CodeGen/MachineCodeEmitter.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/CodeGen/JITCodeEmitter.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineConstantPool.h"
+#include "llvm/CodeGen/MachineJumpTableInfo.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineRelocation.h"
+#include "llvm/ExecutionEngine/GenericValue.h"
+#include "llvm/ExecutionEngine/JITEventListener.h"
+#include "llvm/ExecutionEngine/JITMemoryManager.h"
+#include "llvm/CodeGen/MachineCodeInfo.h"
#include "llvm/Target/TargetData.h"
-#include "Support/Debug.h"
-#include "Support/Statistic.h"
-#include "Config/unistd.h"
-#include "Config/sys/mman.h"
+#include "llvm/Target/TargetJITInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetOptions.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MutexGuard.h"
+#include "llvm/Support/ValueHandle.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/System/Disassembler.h"
+#include "llvm/System/Memory.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Statistic.h"
+#include <algorithm>
+#ifndef NDEBUG
+#include <iomanip>
+#endif
using namespace llvm;
+STATISTIC(NumBytes, "Number of bytes of machine code compiled");
+STATISTIC(NumRelos, "Number of relocations applied");
+STATISTIC(NumRetries, "Number of retries with more memory");
+static JIT *TheJIT = 0;
+
+
+//===----------------------------------------------------------------------===//
+// JIT lazy compilation code.
+//
namespace {
- Statistic<> NumBytes("jit", "Number of bytes of machine code compiled");
- JIT *TheJIT = 0;
-
- /// JITMemoryManager - Manage memory for the JIT code generation in a logical,
- /// sane way. This splits a large block of MAP_NORESERVE'd memory into two
- /// sections, one for function stubs, one for the functions themselves. We
- /// have to do this because we may need to emit a function stub while in the
- /// middle of emitting a function, and we don't know how large the function we
- /// are emitting is. This never bothers to release the memory, because when
- /// we are ready to destroy the JIT, the program exits.
- class JITMemoryManager {
- unsigned char *MemBase; // Base of block of memory, start of stub mem
- unsigned char *FunctionBase; // Start of the function body area
- unsigned char *CurStubPtr, *CurFunctionPtr;
+ class JITResolverState {
+ public:
+ typedef DenseMap<AssertingVH<Function>, void*> FunctionToStubMapTy;
+ typedef std::map<void*, AssertingVH<Function> > CallSiteToFunctionMapTy;
+ typedef DenseMap<AssertingVH<Function>, SmallPtrSet<void*, 1> >
+ FunctionToCallSitesMapTy;
+ typedef std::map<AssertingVH<GlobalValue>, void*> GlobalToIndirectSymMapTy;
+ private:
+ /// FunctionToStubMap - Keep track of the stub created for a particular
+ /// function so that we can reuse them if necessary.
+ FunctionToStubMapTy FunctionToStubMap;
+
+ /// CallSiteToFunctionMap - Keep track of the function that each lazy call
+ /// site corresponds to, and vice versa.
+ CallSiteToFunctionMapTy CallSiteToFunctionMap;
+ FunctionToCallSitesMapTy FunctionToCallSitesMap;
+
+ /// GlobalToIndirectSymMap - Keep track of the indirect symbol created for a
+ /// particular GlobalVariable so that we can reuse them if necessary.
+ GlobalToIndirectSymMapTy GlobalToIndirectSymMap;
+
public:
- JITMemoryManager();
+ FunctionToStubMapTy& getFunctionToStubMap(const MutexGuard& locked) {
+ assert(locked.holds(TheJIT->lock));
+ return FunctionToStubMap;
+ }
+
+ GlobalToIndirectSymMapTy& getGlobalToIndirectSymMap(const MutexGuard& locked) {
+ assert(locked.holds(TheJIT->lock));
+ return GlobalToIndirectSymMap;
+ }
+
+ pair<void *, Function *> LookupFunctionFromCallSite(
+ const MutexGuard &locked, void *CallSite) const {
+ assert(locked.holds(TheJIT->lock));
+
+ // The address given to us for the stub may not be exactly right, it might be
+ // a little bit after the stub. As such, use upper_bound to find it.
+ CallSiteToFunctionMapTy::const_iterator I =
+ CallSiteToFunctionMap.upper_bound(CallSite);
+ assert(I != CallSiteToFunctionMap.begin() &&
+ "This is not a known call site!");
+ --I;
+ return *I;
+ }
+
+ void AddCallSite(const MutexGuard &locked, void *CallSite, Function *F) {
+ assert(locked.holds(TheJIT->lock));
+
+ assert(CallSiteToFunctionMap.insert(std::make_pair(CallSite, F)).second &&
+ "Pair was already in CallSiteToFunctionMap");
+ FunctionToCallSitesMap[F].insert(CallSite);
+ }
+
+ // Returns the Function of the stub if a stub was erased, or NULL if there
+ // was no stub. This function uses the call-site->function map to find a
+ // relevant function, but asserts that only stubs and not other call sites
+ // will be passed in.
+ Function *EraseStub(const MutexGuard &locked, void *Stub) {
+ CallSiteToFunctionMapTy::iterator C2F_I =
+ CallSiteToFunctionMap.find(Stub);
+ if (C2F_I == CallSiteToFunctionMap.end()) {
+ // Not a stub.
+ return NULL;
+ }
+
+ Function *const F = C2F_I->second;
+#ifndef NDEBUG
+ void *RealStub = FunctionToStubMap.lookup(F);
+ assert(RealStub == Stub &&
+ "Call-site that wasn't a stub pass in to EraseStub");
+#endif
+ FunctionToStubMap.erase(F);
+ CallSiteToFunctionMap.erase(C2F_I);
+
+ // Remove the stub from the function->call-sites map, and remove the whole
+ // entry from the map if that was the last call site.
+ FunctionToCallSitesMapTy::iterator F2C_I = FunctionToCallSitesMap.find(F);
+ assert(F2C_I != FunctionToCallSitesMap.end() &&
+ "FunctionToCallSitesMap broken");
+ assert(F2C_I->second.erase(Stub) &&
+ "FunctionToCallSitesMap broken");
+ if (F2C_I->second.empty())
+ FunctionToCallSitesMap.erase(F2C_I);
+
+ return F;
+ }
+
+ void EraseAllCallSites(const MutexGuard &locked, Function *F) {
+ assert(locked.holds(TheJIT->lock));
+ FunctionToCallSitesMapTy::iterator F2C = FunctionToCallSitesMap.find(F);
+ if (F2C == FunctionToCallSitesMap.end())
+ return;
+ for (SmallPtrSet<void*, 1>::const_iterator I = F2C->second.begin(),
+ E = F2C->second.end(); I != E; ++I) {
+ assert(CallSiteToFunctionMap.erase(*I) == 1 &&
+ "Missing call site->function mapping");
+ }
+ FunctionToCallSitesMap.erase(F2C);
+ }
+ };
+
+ /// JITResolver - Keep track of, and resolve, call sites for functions that
+ /// have not yet been compiled.
+ class JITResolver {
+ typedef JITResolverState::FunctionToStubMapTy FunctionToStubMapTy;
+ typedef JITResolverState::CallSiteToFunctionMapTy CallSiteToFunctionMapTy;
+ typedef JITResolverState::GlobalToIndirectSymMapTy GlobalToIndirectSymMapTy;
+
+ /// LazyResolverFn - The target lazy resolver function that we actually
+ /// rewrite instructions to use.
+ TargetJITInfo::LazyResolverFn LazyResolverFn;
+
+ JITResolverState state;
+
+ /// ExternalFnToStubMap - This is the equivalent of FunctionToStubMap for
+ /// external functions.
+ std::map<void*, void*> ExternalFnToStubMap;
+
+ /// revGOTMap - map addresses to indexes in the GOT
+ std::map<void*, unsigned> revGOTMap;
+ unsigned nextGOTIndex;
+
+ static JITResolver *TheJITResolver;
+ public:
+ explicit JITResolver(JIT &jit) : nextGOTIndex(0) {
+ TheJIT = &jit;
+
+ LazyResolverFn = jit.getJITInfo().getLazyResolverFunction(JITCompilerFn);
+ assert(TheJITResolver == 0 && "Multiple JIT resolvers?");
+ TheJITResolver = this;
+ }
+
+ ~JITResolver() {
+ TheJITResolver = 0;
+ }
+
+ /// getFunctionStubIfAvailable - This returns a pointer to a function stub
+ /// if it has already been created.
+ void *getFunctionStubIfAvailable(Function *F);
+
+ /// getFunctionStub - This returns a pointer to a function stub, creating
+ /// one on demand as needed. If empty is true, create a function stub
+ /// pointing at address 0, to be filled in later.
+ void *getFunctionStub(Function *F);
+
+ /// getExternalFunctionStub - Return a stub for the function at the
+ /// specified address, created lazily on demand.
+ void *getExternalFunctionStub(void *FnAddr);
+
+ /// getGlobalValueIndirectSym - Return an indirect symbol containing the
+ /// specified GV address.
+ void *getGlobalValueIndirectSym(GlobalValue *V, void *GVAddress);
+
+ /// AddCallbackAtLocation - If the target is capable of rewriting an
+ /// instruction without the use of a stub, record the location of the use so
+ /// we know which function is being used at the location.
+ void *AddCallbackAtLocation(Function *F, void *Location) {
+ MutexGuard locked(TheJIT->lock);
+ /// Get the target-specific JIT resolver function.
+ state.AddCallSite(locked, Location, F);
+ return (void*)(intptr_t)LazyResolverFn;
+ }
+
+ void getRelocatableGVs(SmallVectorImpl<GlobalValue*> &GVs,
+ SmallVectorImpl<void*> &Ptrs);
- inline unsigned char *allocateStub(unsigned StubSize);
- inline unsigned char *startFunctionBody();
- inline void endFunctionBody(unsigned char *FunctionEnd);
+ GlobalValue *invalidateStub(void *Stub);
+
+ /// getGOTIndexForAddress - Return a new or existing index in the GOT for
+ /// an address. This function only manages slots, it does not manage the
+ /// contents of the slots or the memory associated with the GOT.
+ unsigned getGOTIndexForAddr(void *addr);
+
+ /// JITCompilerFn - This function is called to resolve a stub to a compiled
+ /// address. If the LLVM Function corresponding to the stub has not yet
+ /// been compiled, this function compiles it first.
+ static void *JITCompilerFn(void *Stub);
};
}
-// getMemory - Return a pointer to the specified number of bytes, which is
-// mapped as executable readable and writable.
-static void *getMemory(unsigned NumBytes) {
- if (NumBytes == 0) return 0;
- static const long pageSize = sysconf(_SC_PAGESIZE);
- unsigned NumPages = (NumBytes+pageSize-1)/pageSize;
-
-/* FIXME: This should use the proper autoconf flags */
-#if defined(i386) || defined(__i386__) || defined(__x86__)
- /* Linux and *BSD tend to have these flags named differently. */
-#if defined(MAP_ANON) && !defined(MAP_ANONYMOUS)
-# define MAP_ANONYMOUS MAP_ANON
-#endif /* defined(MAP_ANON) && !defined(MAP_ANONYMOUS) */
-#elif defined(sparc) || defined(__sparc__) || defined(__sparcv9)
-/* nothing */
-#else
- std::cerr << "This architecture is not supported by the JIT!\n";
- abort();
- return 0;
-#endif
+JITResolver *JITResolver::TheJITResolver = 0;
-#ifdef HAVE_MMAP
- int fd = -1;
-#if defined(__linux__)
- fd = 0;
-#endif
+/// getFunctionStubIfAvailable - This returns a pointer to a function stub
+/// if it has already been created.
+void *JITResolver::getFunctionStubIfAvailable(Function *F) {
+ MutexGuard locked(TheJIT->lock);
+
+ // If we already have a stub for this function, recycle it.
+ return state.getFunctionToStubMap(locked).lookup(F);
+}
+
+/// getFunctionStub - This returns a pointer to a function stub, creating
+/// one on demand as needed.
+void *JITResolver::getFunctionStub(Function *F) {
+ MutexGuard locked(TheJIT->lock);
+
+ // If we already have a stub for this function, recycle it.
+ void *&Stub = state.getFunctionToStubMap(locked)[F];
+ if (Stub) return Stub;
+
+ // Call the lazy resolver function unless we are JIT'ing non-lazily, in which
+ // case we must resolve the symbol now.
+ void *Actual = TheJIT->isLazyCompilationDisabled()
+ ? (void *)0 : (void *)(intptr_t)LazyResolverFn;
- unsigned mmapFlags = MAP_PRIVATE|MAP_ANONYMOUS;
-#ifdef MAP_NORESERVE
- mmapFlags |= MAP_NORESERVE;
-#endif
+ // If this is an external declaration, attempt to resolve the address now
+ // to place in the stub.
+ if (F->isDeclaration() && !F->hasNotBeenReadFromBitcode()) {
+ Actual = TheJIT->getPointerToFunction(F);
- void *pa = mmap(0, pageSize*NumPages, PROT_READ|PROT_WRITE|PROT_EXEC,
- mmapFlags, fd, 0);
- if (pa == MAP_FAILED) {
- perror("mmap");
- abort();
+ // If we resolved the symbol to a null address (eg. a weak external)
+ // don't emit a stub. Return a null pointer to the application. If dlsym
+ // stubs are enabled, not being able to resolve the address is not
+ // meaningful.
+ if (!Actual && !TheJIT->areDlsymStubsEnabled()) return 0;
}
- return pa;
-#else
- std::cerr << "Do not know how to allocate mem for the JIT without mmap!\n";
- abort();
- return 0;
-#endif
+
+ // Codegen a new stub, calling the lazy resolver or the actual address of the
+ // external function, if it was resolved.
+ Stub = TheJIT->getJITInfo().emitFunctionStub(F, Actual,
+ *TheJIT->getCodeEmitter());
+
+ if (Actual != (void*)(intptr_t)LazyResolverFn) {
+ // If we are getting the stub for an external function, we really want the
+ // address of the stub in the GlobalAddressMap for the JIT, not the address
+ // of the external function.
+ TheJIT->updateGlobalMapping(F, Stub);
+ }
+
+ DEBUG(errs() << "JIT: Stub emitted at [" << Stub << "] for function '"
+ << F->getName() << "'\n");
+
+ // Finally, keep track of the stub-to-Function mapping so that the
+ // JITCompilerFn knows which function to compile!
+ state.AddCallSite(locked, Stub, F);
+
+ // If we are JIT'ing non-lazily but need to call a function that does not
+ // exist yet, add it to the JIT's work list so that we can fill in the stub
+ // address later.
+ if (!Actual && TheJIT->isLazyCompilationDisabled())
+ if (!F->isDeclaration() || F->hasNotBeenReadFromBitcode())
+ TheJIT->addPendingFunction(F);
+
+ return Stub;
+}
+
+/// getGlobalValueIndirectSym - Return a lazy pointer containing the specified
+/// GV address.
+void *JITResolver::getGlobalValueIndirectSym(GlobalValue *GV, void *GVAddress) {
+ MutexGuard locked(TheJIT->lock);
+
+ // If we already have a stub for this global variable, recycle it.
+ void *&IndirectSym = state.getGlobalToIndirectSymMap(locked)[GV];
+ if (IndirectSym) return IndirectSym;
+
+ // Otherwise, codegen a new indirect symbol.
+ IndirectSym = TheJIT->getJITInfo().emitGlobalValueIndirectSym(GV, GVAddress,
+ *TheJIT->getCodeEmitter());
+
+ DEBUG(errs() << "JIT: Indirect symbol emitted at [" << IndirectSym
+ << "] for GV '" << GV->getName() << "'\n");
+
+ return IndirectSym;
}
-JITMemoryManager::JITMemoryManager() {
- // Allocate a 16M block of memory...
- MemBase = (unsigned char*)getMemory(16 << 20);
- FunctionBase = MemBase + 512*1024; // Use 512k for stubs
+/// getExternalFunctionStub - Return a stub for the function at the
+/// specified address, created lazily on demand.
+void *JITResolver::getExternalFunctionStub(void *FnAddr) {
+ // If we already have a stub for this function, recycle it.
+ void *&Stub = ExternalFnToStubMap[FnAddr];
+ if (Stub) return Stub;
+
+ Stub = TheJIT->getJITInfo().emitFunctionStub(0, FnAddr,
+ *TheJIT->getCodeEmitter());
- // Allocate stubs backwards from the function base, allocate functions forward
- // from the function base.
- CurStubPtr = CurFunctionPtr = FunctionBase;
+ DEBUG(errs() << "JIT: Stub emitted at [" << Stub
+ << "] for external function at '" << FnAddr << "'\n");
+ return Stub;
}
-unsigned char *JITMemoryManager::allocateStub(unsigned StubSize) {
- CurStubPtr -= StubSize;
- if (CurStubPtr < MemBase) {
- std::cerr << "JIT ran out of memory for function stubs!\n";
- abort();
+unsigned JITResolver::getGOTIndexForAddr(void* addr) {
+ unsigned idx = revGOTMap[addr];
+ if (!idx) {
+ idx = ++nextGOTIndex;
+ revGOTMap[addr] = idx;
+ DEBUG(errs() << "JIT: Adding GOT entry " << idx << " for addr ["
+ << addr << "]\n");
}
- return CurStubPtr;
+ return idx;
}
-unsigned char *JITMemoryManager::startFunctionBody() {
- // Round up to an even multiple of 4 bytes, this should eventually be target
- // specific.
- return (unsigned char*)(((intptr_t)CurFunctionPtr + 3) & ~3);
+void JITResolver::getRelocatableGVs(SmallVectorImpl<GlobalValue*> &GVs,
+ SmallVectorImpl<void*> &Ptrs) {
+ MutexGuard locked(TheJIT->lock);
+
+ const FunctionToStubMapTy &FM = state.getFunctionToStubMap(locked);
+ GlobalToIndirectSymMapTy &GM = state.getGlobalToIndirectSymMap(locked);
+
+ for (FunctionToStubMapTy::const_iterator i = FM.begin(), e = FM.end();
+ i != e; ++i){
+ Function *F = i->first;
+ if (F->isDeclaration() && F->hasExternalLinkage()) {
+ GVs.push_back(i->first);
+ Ptrs.push_back(i->second);
+ }
+ }
+ for (GlobalToIndirectSymMapTy::iterator i = GM.begin(), e = GM.end();
+ i != e; ++i) {
+ GVs.push_back(i->first);
+ Ptrs.push_back(i->second);
+ }
}
-void JITMemoryManager::endFunctionBody(unsigned char *FunctionEnd) {
- assert(FunctionEnd > CurFunctionPtr);
- CurFunctionPtr = FunctionEnd;
+GlobalValue *JITResolver::invalidateStub(void *Stub) {
+ MutexGuard locked(TheJIT->lock);
+
+ GlobalToIndirectSymMapTy &GM = state.getGlobalToIndirectSymMap(locked);
+
+ // Look up the cheap way first, to see if it's a function stub we are
+ // invalidating. If so, remove it from both the forward and reverse maps.
+ if (Function *F = state.EraseStub(locked, Stub)) {
+ return F;
+ }
+
+ // Otherwise, it might be an indirect symbol stub. Find it and remove it.
+ for (GlobalToIndirectSymMapTy::iterator i = GM.begin(), e = GM.end();
+ i != e; ++i) {
+ if (i->second != Stub)
+ continue;
+ GlobalValue *GV = i->first;
+ GM.erase(i);
+ return GV;
+ }
+
+ // Lastly, check to see if it's in the ExternalFnToStubMap.
+ for (std::map<void *, void *>::iterator i = ExternalFnToStubMap.begin(),
+ e = ExternalFnToStubMap.end(); i != e; ++i) {
+ if (i->second != Stub)
+ continue;
+ ExternalFnToStubMap.erase(i);
+ break;
+ }
+
+ return 0;
}
+/// JITCompilerFn - This function is called when a lazy compilation stub has
+/// been entered. It looks up which function this stub corresponds to, compiles
+/// it if necessary, then returns the resultant function pointer.
+void *JITResolver::JITCompilerFn(void *Stub) {
+ JITResolver &JR = *TheJITResolver;
+
+ Function* F = 0;
+ void* ActualPtr = 0;
+ {
+ // Only lock for getting the Function. The call getPointerToFunction made
+ // in this function might trigger function materializing, which requires
+ // JIT lock to be unlocked.
+ MutexGuard locked(TheJIT->lock);
-namespace {
- /// Emitter - The JIT implementation of the MachineCodeEmitter, which is used
- /// to output functions to memory for execution.
- class Emitter : public MachineCodeEmitter {
- JITMemoryManager MemMgr;
+ // The address given to us for the stub may not be exactly right, it might
+ // be a little bit after the stub. As such, use upper_bound to find it.
+ pair<void*, Function*> I =
+ JR.state.LookupFunctionFromCallSite(locked, Stub);
+ F = I.second;
+ ActualPtr = I.first;
+ }
+
+ // If we have already code generated the function, just return the address.
+ void *Result = TheJIT->getPointerToGlobalIfAvailable(F);
+
+ if (!Result) {
+ // Otherwise we don't have it, do lazy compilation now.
+
+ // If lazy compilation is disabled, emit a useful error message and abort.
+ if (TheJIT->isLazyCompilationDisabled()) {
+ llvm_report_error("LLVM JIT requested to do lazy compilation of function '"
+ + F->getName() + "' when lazy compiles are disabled!");
+ }
+
+ DEBUG(errs() << "JIT: Lazily resolving function '" << F->getName()
+ << "' In stub ptr = " << Stub << " actual ptr = "
+ << ActualPtr << "\n");
+
+ Result = TheJIT->getPointerToFunction(F);
+ }
+
+ // Reacquire the lock to update the GOT map.
+ MutexGuard locked(TheJIT->lock);
+
+ // We might like to remove the call site from the CallSiteToFunction map, but
+ // we can't do that! Multiple threads could be stuck, waiting to acquire the
+ // lock above. As soon as the 1st function finishes compiling the function,
+ // the next one will be released, and needs to be able to find the function it
+ // needs to call.
+
+ // FIXME: We could rewrite all references to this stub if we knew them.
+
+ // What we will do is set the compiled function address to map to the
+ // same GOT entry as the stub so that later clients may update the GOT
+ // if they see it still using the stub address.
+ // Note: this is done so the Resolver doesn't have to manage GOT memory
+ // Do this without allocating map space if the target isn't using a GOT
+ if(JR.revGOTMap.find(Stub) != JR.revGOTMap.end())
+ JR.revGOTMap[Result] = JR.revGOTMap[Stub];
- // CurBlock - The start of the current block of memory. CurByte - The
- // current byte being emitted to.
- unsigned char *CurBlock, *CurByte;
+ return Result;
+}
+
+//===----------------------------------------------------------------------===//
+// JITEmitter code.
+//
+namespace {
+ /// JITEmitter - The JIT implementation of the MachineCodeEmitter, which is
+ /// used to output functions to memory for execution.
+ class JITEmitter : public JITCodeEmitter {
+ JITMemoryManager *MemMgr;
// When outputting a function stub in the context of some other function, we
- // save CurBlock and CurByte here.
- unsigned char *SavedCurBlock, *SavedCurByte;
+ // save BufferBegin/BufferEnd/CurBufferPtr here.
+ uint8_t *SavedBufferBegin, *SavedBufferEnd, *SavedCurBufferPtr;
+
+ // When reattempting to JIT a function after running out of space, we store
+ // the estimated size of the function we're trying to JIT here, so we can
+ // ask the memory manager for at least this much space. When we
+ // successfully emit the function, we reset this back to zero.
+ uintptr_t SizeEstimate;
+
+ /// Relocations - These are the relocations that the function needs, as
+ /// emitted.
+ std::vector<MachineRelocation> Relocations;
+
+ /// MBBLocations - This vector is a mapping from MBB ID's to their address.
+ /// It is filled in by the StartMachineBasicBlock callback and queried by
+ /// the getMachineBasicBlockAddress callback.
+ std::vector<uintptr_t> MBBLocations;
+
+ /// ConstantPool - The constant pool for the current function.
+ ///
+ MachineConstantPool *ConstantPool;
+
+ /// ConstantPoolBase - A pointer to the first entry in the constant pool.
+ ///
+ void *ConstantPoolBase;
+
+ /// ConstPoolAddresses - Addresses of individual constant pool entries.
+ ///
+ SmallVector<uintptr_t, 8> ConstPoolAddresses;
+
+ /// JumpTable - The jump tables for the current function.
+ ///
+ MachineJumpTableInfo *JumpTable;
+
+ /// JumpTableBase - A pointer to the first entry in the jump table.
+ ///
+ void *JumpTableBase;
+
+ /// Resolver - This contains info about the currently resolved functions.
+ JITResolver Resolver;
+
+ /// DE - The dwarf emitter for the jit.
+ OwningPtr<JITDwarfEmitter> DE;
+
+ /// DR - The debug registerer for the jit.
+ OwningPtr<JITDebugRegisterer> DR;
+
+ /// LabelLocations - This vector is a mapping from Label ID's to their
+ /// address.
+ std::vector<uintptr_t> LabelLocations;
+
+ /// MMI - Machine module info for exception informations
+ MachineModuleInfo* MMI;
+
+ // GVSet - a set to keep track of which globals have been seen
+ SmallPtrSet<const GlobalVariable*, 8> GVSet;
+
+ // CurFn - The llvm function being emitted. Only valid during
+ // finishFunction().
+ const Function *CurFn;
+
+ /// Information about emitted code, which is passed to the
+ /// JITEventListeners. This is reset in startFunction and used in
+ /// finishFunction.
+ JITEvent_EmittedFunctionDetails EmissionDetails;
+
+ // CurFnStubUses - For a given Function, a vector of stubs that it
+ // references. This facilitates the JIT detecting that a stub is no
+ // longer used, so that it may be deallocated.
+ DenseMap<const Function *, SmallVector<void*, 1> > CurFnStubUses;
+
+ // StubFnRefs - For a given pointer to a stub, a set of Functions which
+ // reference the stub. When the count of a stub's references drops to zero,
+ // the stub is unused.
+ DenseMap<void *, SmallPtrSet<const Function*, 1> > StubFnRefs;
+
+ // ExtFnStubs - A map of external function names to stubs which have entries
+ // in the JITResolver's ExternalFnToStubMap.
+ StringMap<void *> ExtFnStubs;
+
+ DebugLocTuple PrevDLT;
- // ConstantPoolAddresses - Contains the location for each entry in the
- // constant pool.
- std::vector<void*> ConstantPoolAddresses;
public:
- Emitter(JIT &jit) { TheJIT = &jit; }
+ JITEmitter(JIT &jit, JITMemoryManager *JMM, TargetMachine &TM)
+ : SizeEstimate(0), Resolver(jit), MMI(0), CurFn(0) {
+ MemMgr = JMM ? JMM : JITMemoryManager::CreateDefaultMemManager();
+ if (jit.getJITInfo().needsGOT()) {
+ MemMgr->AllocateGOT();
+ DEBUG(errs() << "JIT is managing a GOT\n");
+ }
+
+ if (DwarfExceptionHandling || JITEmitDebugInfo) {
+ DE.reset(new JITDwarfEmitter(jit));
+ }
+ if (JITEmitDebugInfo) {
+ DR.reset(new JITDebugRegisterer(TM));
+ }
+ }
+ ~JITEmitter() {
+ delete MemMgr;
+ }
+
+ /// classof - Methods for support type inquiry through isa, cast, and
+ /// dyn_cast:
+ ///
+ static inline bool classof(const JITEmitter*) { return true; }
+ static inline bool classof(const MachineCodeEmitter*) { return true; }
+
+ JITResolver &getJITResolver() { return Resolver; }
virtual void startFunction(MachineFunction &F);
- virtual void finishFunction(MachineFunction &F);
- virtual void emitConstantPool(MachineConstantPool *MCP);
- virtual void startFunctionStub(const Function &F, unsigned StubSize);
- virtual void* finishFunctionStub(const Function &F);
- virtual void emitByte(unsigned char B);
- virtual void emitWord(unsigned W);
- virtual void emitWordAt(unsigned W, unsigned *Ptr);
-
- virtual uint64_t getGlobalValueAddress(GlobalValue *V);
- virtual uint64_t getGlobalValueAddress(const std::string &Name);
- virtual uint64_t getConstantPoolEntryAddress(unsigned Entry);
- virtual uint64_t getCurrentPCValue();
-
- // forceCompilationOf - Force the compilation of the specified function, and
- // return its address, because we REALLY need the address now.
- //
- // FIXME: This is JIT specific!
- //
- virtual uint64_t forceCompilationOf(Function *F);
+ virtual bool finishFunction(MachineFunction &F);
+
+ void emitConstantPool(MachineConstantPool *MCP);
+ void initJumpTableInfo(MachineJumpTableInfo *MJTI);
+ void emitJumpTableInfo(MachineJumpTableInfo *MJTI);
+
+ virtual void startGVStub(const GlobalValue* GV, unsigned StubSize,
+ unsigned Alignment = 1);
+ virtual void startGVStub(const GlobalValue* GV, void *Buffer,
+ unsigned StubSize);
+ virtual void* finishGVStub(const GlobalValue *GV);
+
+ /// allocateSpace - Reserves space in the current block if any, or
+ /// allocate a new one of the given size.
+ virtual void *allocateSpace(uintptr_t Size, unsigned Alignment);
+
+ /// allocateGlobal - Allocate memory for a global. Unlike allocateSpace,
+ /// this method does not allocate memory in the current output buffer,
+ /// because a global may live longer than the current function.
+ virtual void *allocateGlobal(uintptr_t Size, unsigned Alignment);
+
+ virtual void addRelocation(const MachineRelocation &MR) {
+ Relocations.push_back(MR);
+ }
+
+ virtual void StartMachineBasicBlock(MachineBasicBlock *MBB) {
+ if (MBBLocations.size() <= (unsigned)MBB->getNumber())
+ MBBLocations.resize((MBB->getNumber()+1)*2);
+ MBBLocations[MBB->getNumber()] = getCurrentPCValue();
+ DEBUG(errs() << "JIT: Emitting BB" << MBB->getNumber() << " at ["
+ << (void*) getCurrentPCValue() << "]\n");
+ }
+
+ virtual uintptr_t getConstantPoolEntryAddress(unsigned Entry) const;
+ virtual uintptr_t getJumpTableEntryAddress(unsigned Entry) const;
+
+ virtual uintptr_t getMachineBasicBlockAddress(MachineBasicBlock *MBB) const {
+ assert(MBBLocations.size() > (unsigned)MBB->getNumber() &&
+ MBBLocations[MBB->getNumber()] && "MBB not emitted!");
+ return MBBLocations[MBB->getNumber()];
+ }
+
+ /// retryWithMoreMemory - Log a retry and deallocate all memory for the
+ /// given function. Increase the minimum allocation size so that we get
+ /// more memory next time.
+ void retryWithMoreMemory(MachineFunction &F);
+
+ /// deallocateMemForFunction - Deallocate all memory for the specified
+ /// function body.
+ void deallocateMemForFunction(const Function *F);
+
+ /// AddStubToCurrentFunction - Mark the current function being JIT'd as
+ /// using the stub at the specified address. Allows
+ /// deallocateMemForFunction to also remove stubs no longer referenced.
+ void AddStubToCurrentFunction(void *Stub);
+
+ /// getExternalFnStubs - Accessor for the JIT to find stubs emitted for
+ /// MachineRelocations that reference external functions by name.
+ const StringMap<void*> &getExternalFnStubs() const { return ExtFnStubs; }
+
+ virtual void processDebugLoc(DebugLoc DL, bool BeforePrintingInsn);
+
+ virtual void emitLabel(uint64_t LabelID) {
+ if (LabelLocations.size() <= LabelID)
+ LabelLocations.resize((LabelID+1)*2);
+ LabelLocations[LabelID] = getCurrentPCValue();
+ }
+
+ virtual uintptr_t getLabelAddress(uint64_t LabelID) const {
+ assert(LabelLocations.size() > (unsigned)LabelID &&
+ LabelLocations[LabelID] && "Label not emitted!");
+ return LabelLocations[LabelID];
+ }
+
+ virtual void setModuleInfo(MachineModuleInfo* Info) {
+ MMI = Info;
+ if (DE.get()) DE->setModuleInfo(Info);
+ }
+
+ void setMemoryExecutable() {
+ MemMgr->setMemoryExecutable();
+ }
+
+ JITMemoryManager *getMemMgr() const { return MemMgr; }
+
+ private:
+ void *getPointerToGlobal(GlobalValue *GV, void *Reference, bool NoNeedStub);
+ void *getPointerToGVIndirectSym(GlobalValue *V, void *Reference,
+ bool NoNeedStub);
+ unsigned addSizeOfGlobal(const GlobalVariable *GV, unsigned Size);
+ unsigned addSizeOfGlobalsInConstantVal(const Constant *C, unsigned Size);
+ unsigned addSizeOfGlobalsInInitializer(const Constant *Init, unsigned Size);
+ unsigned GetSizeOfGlobalsInBytes(MachineFunction &MF);
};
}
-MachineCodeEmitter *JIT::createEmitter(JIT &jit) {
- return new Emitter(jit);
+void *JITEmitter::getPointerToGlobal(GlobalValue *V, void *Reference,
+ bool DoesntNeedStub) {
+ if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V))
+ return TheJIT->getOrEmitGlobalVariable(GV);
+
+ if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V))
+ return TheJIT->getPointerToGlobal(GA->resolveAliasedGlobal(false));
+
+ // If we have already compiled the function, return a pointer to its body.
+ Function *F = cast<Function>(V);
+ void *ResultPtr;
+ if (!DoesntNeedStub) {
+ // Return the function stub if it's already created.
+ ResultPtr = Resolver.getFunctionStubIfAvailable(F);
+ if (ResultPtr)
+ AddStubToCurrentFunction(ResultPtr);
+ } else {
+ ResultPtr = TheJIT->getPointerToGlobalIfAvailable(F);
+ }
+ if (ResultPtr) return ResultPtr;
+
+ // If this is an external function pointer, we can force the JIT to
+ // 'compile' it, which really just adds it to the map. In dlsym mode,
+ // external functions are forced through a stub, regardless of reloc type.
+ if (F->isDeclaration() && !F->hasNotBeenReadFromBitcode() &&
+ DoesntNeedStub && !TheJIT->areDlsymStubsEnabled())
+ return TheJIT->getPointerToFunction(F);
+
+ // Okay, the function has not been compiled yet, if the target callback
+ // mechanism is capable of rewriting the instruction directly, prefer to do
+ // that instead of emitting a stub. This uses the lazy resolver, so is not
+ // legal if lazy compilation is disabled.
+ if (DoesntNeedStub && !TheJIT->isLazyCompilationDisabled())
+ return Resolver.AddCallbackAtLocation(F, Reference);
+
+ // Otherwise, we have to emit a stub.
+ void *StubAddr = Resolver.getFunctionStub(F);
+
+ // Add the stub to the current function's list of referenced stubs, so we can
+ // deallocate them if the current function is ever freed. It's possible to
+ // return null from getFunctionStub in the case of a weak extern that fails
+ // to resolve.
+ if (StubAddr)
+ AddStubToCurrentFunction(StubAddr);
+
+ return StubAddr;
}
-void Emitter::startFunction(MachineFunction &F) {
- CurByte = CurBlock = MemMgr.startFunctionBody();
- TheJIT->addGlobalMapping(F.getFunction(), CurBlock);
+void *JITEmitter::getPointerToGVIndirectSym(GlobalValue *V, void *Reference,
+ bool NoNeedStub) {
+ // Make sure GV is emitted first, and create a stub containing the fully
+ // resolved address.
+ void *GVAddress = getPointerToGlobal(V, Reference, true);
+ void *StubAddr = Resolver.getGlobalValueIndirectSym(V, GVAddress);
+
+ // Add the stub to the current function's list of referenced stubs, so we can
+ // deallocate them if the current function is ever freed.
+ AddStubToCurrentFunction(StubAddr);
+
+ return StubAddr;
}
-void Emitter::finishFunction(MachineFunction &F) {
- MemMgr.endFunctionBody(CurByte);
- ConstantPoolAddresses.clear();
- NumBytes += CurByte-CurBlock;
+void JITEmitter::AddStubToCurrentFunction(void *StubAddr) {
+ assert(CurFn && "Stub added to current function, but current function is 0!");
- DEBUG(std::cerr << "Finished CodeGen of [" << (void*)CurBlock
- << "] Function: " << F.getFunction()->getName()
- << ": " << CurByte-CurBlock << " bytes of text\n");
+ SmallVectorImpl<void*> &StubsUsed = CurFnStubUses[CurFn];
+ StubsUsed.push_back(StubAddr);
+
+ SmallPtrSet<const Function *, 1> &FnRefs = StubFnRefs[StubAddr];
+ FnRefs.insert(CurFn);
}
-void Emitter::emitConstantPool(MachineConstantPool *MCP) {
- const std::vector<Constant*> &Constants = MCP->getConstants();
- if (Constants.empty()) return;
+void JITEmitter::processDebugLoc(DebugLoc DL, bool BeforePrintingInsn) {
+ if (!DL.isUnknown()) {
+ DebugLocTuple CurDLT = EmissionDetails.MF->getDebugLocTuple(DL);
+
+ if (BeforePrintingInsn) {
+ if (CurDLT.Scope != 0 && PrevDLT != CurDLT) {
+ JITEvent_EmittedFunctionDetails::LineStart NextLine;
+ NextLine.Address = getCurrentPCValue();
+ NextLine.Loc = DL;
+ EmissionDetails.LineStarts.push_back(NextLine);
+ }
+
+ PrevDLT = CurDLT;
+ }
+ }
+}
- std::vector<unsigned> ConstantOffset;
- ConstantOffset.reserve(Constants.size());
+static unsigned GetConstantPoolSizeInBytes(MachineConstantPool *MCP,
+ const TargetData *TD) {
+ const std::vector<MachineConstantPoolEntry> &Constants = MCP->getConstants();
+ if (Constants.empty()) return 0;
- // Calculate how much space we will need for all the constants, and the offset
- // each one will live in.
- unsigned TotalSize = 0;
+ unsigned Size = 0;
for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
- const Type *Ty = Constants[i]->getType();
- unsigned Size = TheJIT->getTargetData().getTypeSize(Ty);
- unsigned Alignment = TheJIT->getTargetData().getTypeAlignment(Ty);
- // Make sure to take into account the alignment requirements of the type.
- TotalSize = (TotalSize + Alignment-1) & ~(Alignment-1);
-
- // Remember the offset this element lives at.
- ConstantOffset.push_back(TotalSize);
- TotalSize += Size; // Reserve space for the constant.
+ MachineConstantPoolEntry CPE = Constants[i];
+ unsigned AlignMask = CPE.getAlignment() - 1;
+ Size = (Size + AlignMask) & ~AlignMask;
+ const Type *Ty = CPE.getType();
+ Size += TD->getTypeAllocSize(Ty);
}
+ return Size;
+}
- // Now that we know how much memory to allocate, do so.
- char *Pool = new char[TotalSize];
+static unsigned GetJumpTableSizeInBytes(MachineJumpTableInfo *MJTI) {
+ const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
+ if (JT.empty()) return 0;
+
+ unsigned NumEntries = 0;
+ for (unsigned i = 0, e = JT.size(); i != e; ++i)
+ NumEntries += JT[i].MBBs.size();
- // Actually output all of the constants, and remember their addresses.
- for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
- void *Addr = Pool + ConstantOffset[i];
- TheJIT->InitializeMemory(Constants[i], Addr);
- ConstantPoolAddresses.push_back(Addr);
+ unsigned EntrySize = MJTI->getEntrySize();
+
+ return NumEntries * EntrySize;
+}
+
+static uintptr_t RoundUpToAlign(uintptr_t Size, unsigned Alignment) {
+ if (Alignment == 0) Alignment = 1;
+ // Since we do not know where the buffer will be allocated, be pessimistic.
+ return Size + Alignment;
+}
+
+/// addSizeOfGlobal - add the size of the global (plus any alignment padding)
+/// into the running total Size.
+
+unsigned JITEmitter::addSizeOfGlobal(const GlobalVariable *GV, unsigned Size) {
+ const Type *ElTy = GV->getType()->getElementType();
+ size_t GVSize = (size_t)TheJIT->getTargetData()->getTypeAllocSize(ElTy);
+ size_t GVAlign =
+ (size_t)TheJIT->getTargetData()->getPreferredAlignment(GV);
+ DEBUG(errs() << "JIT: Adding in size " << GVSize << " alignment " << GVAlign);
+ DEBUG(GV->dump());
+ // Assume code section ends with worst possible alignment, so first
+ // variable needs maximal padding.
+ if (Size==0)
+ Size = 1;
+ Size = ((Size+GVAlign-1)/GVAlign)*GVAlign;
+ Size += GVSize;
+ return Size;
+}
+
+/// addSizeOfGlobalsInConstantVal - find any globals that we haven't seen yet
+/// but are referenced from the constant; put them in GVSet and add their
+/// size into the running total Size.
+
+unsigned JITEmitter::addSizeOfGlobalsInConstantVal(const Constant *C,
+ unsigned Size) {
+ // If its undefined, return the garbage.
+ if (isa<UndefValue>(C))
+ return Size;
+
+ // If the value is a ConstantExpr
+ if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
+ Constant *Op0 = CE->getOperand(0);
+ switch (CE->getOpcode()) {
+ case Instruction::GetElementPtr:
+ case Instruction::Trunc:
+ case Instruction::ZExt:
+ case Instruction::SExt:
+ case Instruction::FPTrunc:
+ case Instruction::FPExt:
+ case Instruction::UIToFP:
+ case Instruction::SIToFP:
+ case Instruction::FPToUI:
+ case Instruction::FPToSI:
+ case Instruction::PtrToInt:
+ case Instruction::IntToPtr:
+ case Instruction::BitCast: {
+ Size = addSizeOfGlobalsInConstantVal(Op0, Size);
+ break;
+ }
+ case Instruction::Add:
+ case Instruction::FAdd:
+ case Instruction::Sub:
+ case Instruction::FSub:
+ case Instruction::Mul:
+ case Instruction::FMul:
+ case Instruction::UDiv:
+ case Instruction::SDiv:
+ case Instruction::URem:
+ case Instruction::SRem:
+ case Instruction::And:
+ case Instruction::Or:
+ case Instruction::Xor: {
+ Size = addSizeOfGlobalsInConstantVal(Op0, Size);
+ Size = addSizeOfGlobalsInConstantVal(CE->getOperand(1), Size);
+ break;
+ }
+ default: {
+ std::string msg;
+ raw_string_ostream Msg(msg);
+ Msg << "ConstantExpr not handled: " << *CE;
+ llvm_report_error(Msg.str());
+ }
+ }
}
+
+ if (C->getType()->getTypeID() == Type::PointerTyID)
+ if (const GlobalVariable* GV = dyn_cast<GlobalVariable>(C))
+ if (GVSet.insert(GV))
+ Size = addSizeOfGlobal(GV, Size);
+
+ return Size;
+}
+
+/// addSizeOfGLobalsInInitializer - handle any globals that we haven't seen yet
+/// but are referenced from the given initializer.
+
+unsigned JITEmitter::addSizeOfGlobalsInInitializer(const Constant *Init,
+ unsigned Size) {
+ if (!isa<UndefValue>(Init) &&
+ !isa<ConstantVector>(Init) &&
+ !isa<ConstantAggregateZero>(Init) &&
+ !isa<ConstantArray>(Init) &&
+ !isa<ConstantStruct>(Init) &&
+ Init->getType()->isFirstClassType())
+ Size = addSizeOfGlobalsInConstantVal(Init, Size);
+ return Size;
+}
+
+/// GetSizeOfGlobalsInBytes - walk the code for the function, looking for
+/// globals; then walk the initializers of those globals looking for more.
+/// If their size has not been considered yet, add it into the running total
+/// Size.
+
+unsigned JITEmitter::GetSizeOfGlobalsInBytes(MachineFunction &MF) {
+ unsigned Size = 0;
+ GVSet.clear();
+
+ for (MachineFunction::iterator MBB = MF.begin(), E = MF.end();
+ MBB != E; ++MBB) {
+ for (MachineBasicBlock::const_iterator I = MBB->begin(), E = MBB->end();
+ I != E; ++I) {
+ const TargetInstrDesc &Desc = I->getDesc();
+ const MachineInstr &MI = *I;
+ unsigned NumOps = Desc.getNumOperands();
+ for (unsigned CurOp = 0; CurOp < NumOps; CurOp++) {
+ const MachineOperand &MO = MI.getOperand(CurOp);
+ if (MO.isGlobal()) {
+ GlobalValue* V = MO.getGlobal();
+ const GlobalVariable *GV = dyn_cast<const GlobalVariable>(V);
+ if (!GV)
+ continue;
+ // If seen in previous function, it will have an entry here.
+ if (TheJIT->getPointerToGlobalIfAvailable(GV))
+ continue;
+ // If seen earlier in this function, it will have an entry here.
+ // FIXME: it should be possible to combine these tables, by
+ // assuming the addresses of the new globals in this module
+ // start at 0 (or something) and adjusting them after codegen
+ // complete. Another possibility is to grab a marker bit in GV.
+ if (GVSet.insert(GV))
+ // A variable as yet unseen. Add in its size.
+ Size = addSizeOfGlobal(GV, Size);
+ }
+ }
+ }
+ }
+ DEBUG(errs() << "JIT: About to look through initializers\n");
+ // Look for more globals that are referenced only from initializers.
+ // GVSet.end is computed each time because the set can grow as we go.
+ for (SmallPtrSet<const GlobalVariable *, 8>::iterator I = GVSet.begin();
+ I != GVSet.end(); I++) {
+ const GlobalVariable* GV = *I;
+ if (GV->hasInitializer())
+ Size = addSizeOfGlobalsInInitializer(GV->getInitializer(), Size);
+ }
+
+ return Size;
+}
+
+void JITEmitter::startFunction(MachineFunction &F) {
+ DEBUG(errs() << "JIT: Starting CodeGen of Function "
+ << F.getFunction()->getName() << "\n");
+
+ uintptr_t ActualSize = 0;
+ // Set the memory writable, if it's not already
+ MemMgr->setMemoryWritable();
+ if (MemMgr->NeedsExactSize()) {
+ DEBUG(errs() << "JIT: ExactSize\n");
+ const TargetInstrInfo* TII = F.getTarget().getInstrInfo();
+ MachineJumpTableInfo *MJTI = F.getJumpTableInfo();
+ MachineConstantPool *MCP = F.getConstantPool();
+
+ // Ensure the constant pool/jump table info is at least 4-byte aligned.
+ ActualSize = RoundUpToAlign(ActualSize, 16);
+
+ // Add the alignment of the constant pool
+ ActualSize = RoundUpToAlign(ActualSize, MCP->getConstantPoolAlignment());
+
+ // Add the constant pool size
+ ActualSize += GetConstantPoolSizeInBytes(MCP, TheJIT->getTargetData());
+
+ // Add the aligment of the jump table info
+ ActualSize = RoundUpToAlign(ActualSize, MJTI->getAlignment());
+
+ // Add the jump table size
+ ActualSize += GetJumpTableSizeInBytes(MJTI);
+
+ // Add the alignment for the function
+ ActualSize = RoundUpToAlign(ActualSize,
+ std::max(F.getFunction()->getAlignment(), 8U));
+
+ // Add the function size
+ ActualSize += TII->GetFunctionSizeInBytes(F);
+
+ DEBUG(errs() << "JIT: ActualSize before globals " << ActualSize << "\n");
+ // Add the size of the globals that will be allocated after this function.
+ // These are all the ones referenced from this function that were not
+ // previously allocated.
+ ActualSize += GetSizeOfGlobalsInBytes(F);
+ DEBUG(errs() << "JIT: ActualSize after globals " << ActualSize << "\n");
+ } else if (SizeEstimate > 0) {
+ // SizeEstimate will be non-zero on reallocation attempts.
+ ActualSize = SizeEstimate;
+ }
+
+ BufferBegin = CurBufferPtr = MemMgr->startFunctionBody(F.getFunction(),
+ ActualSize);
+ BufferEnd = BufferBegin+ActualSize;
+
+ // Ensure the constant pool/jump table info is at least 4-byte aligned.
+ emitAlignment(16);
+
+ emitConstantPool(F.getConstantPool());
+ initJumpTableInfo(F.getJumpTableInfo());
+
+ // About to start emitting the machine code for the function.
+ emitAlignment(std::max(F.getFunction()->getAlignment(), 8U));
+ TheJIT->updateGlobalMapping(F.getFunction(), CurBufferPtr);
+
+ MBBLocations.clear();
+
+ EmissionDetails.MF = &F;
+ EmissionDetails.LineStarts.clear();
+}
+
+bool JITEmitter::finishFunction(MachineFunction &F) {
+ if (CurBufferPtr == BufferEnd) {
+ // We must call endFunctionBody before retrying, because
+ // deallocateMemForFunction requires it.
+ MemMgr->endFunctionBody(F.getFunction(), BufferBegin, CurBufferPtr);
+ retryWithMoreMemory(F);
+ return true;
+ }
+
+ emitJumpTableInfo(F.getJumpTableInfo());
+
+ // FnStart is the start of the text, not the start of the constant pool and
+ // other per-function data.
+ uint8_t *FnStart =
+ (uint8_t *)TheJIT->getPointerToGlobalIfAvailable(F.getFunction());
+
+ // FnEnd is the end of the function's machine code.
+ uint8_t *FnEnd = CurBufferPtr;
+
+ if (!Relocations.empty()) {
+ CurFn = F.getFunction();
+ NumRelos += Relocations.size();
+
+ // Resolve the relocations to concrete pointers.
+ for (unsigned i = 0, e = Relocations.size(); i != e; ++i) {
+ MachineRelocation &MR = Relocations[i];
+ void *ResultPtr = 0;
+ if (!MR.letTargetResolve()) {
+ if (MR.isExternalSymbol()) {
+ ResultPtr = TheJIT->getPointerToNamedFunction(MR.getExternalSymbol(),
+ false);
+ DEBUG(errs() << "JIT: Map \'" << MR.getExternalSymbol() << "\' to ["
+ << ResultPtr << "]\n");
+
+ // If the target REALLY wants a stub for this function, emit it now.
+ if (!MR.doesntNeedStub()) {
+ if (!TheJIT->areDlsymStubsEnabled()) {
+ ResultPtr = Resolver.getExternalFunctionStub(ResultPtr);
+ } else {
+ void *&Stub = ExtFnStubs[MR.getExternalSymbol()];
+ if (!Stub) {
+ Stub = Resolver.getExternalFunctionStub((void *)&Stub);
+ AddStubToCurrentFunction(Stub);
+ }
+ ResultPtr = Stub;
+ }
+ }
+ } else if (MR.isGlobalValue()) {
+ ResultPtr = getPointerToGlobal(MR.getGlobalValue(),
+ BufferBegin+MR.getMachineCodeOffset(),
+ MR.doesntNeedStub());
+ } else if (MR.isIndirectSymbol()) {
+ ResultPtr = getPointerToGVIndirectSym(MR.getGlobalValue(),
+ BufferBegin+MR.getMachineCodeOffset(),
+ MR.doesntNeedStub());
+ } else if (MR.isBasicBlock()) {
+ ResultPtr = (void*)getMachineBasicBlockAddress(MR.getBasicBlock());
+ } else if (MR.isConstantPoolIndex()) {
+ ResultPtr = (void*)getConstantPoolEntryAddress(MR.getConstantPoolIndex());
+ } else {
+ assert(MR.isJumpTableIndex());
+ ResultPtr=(void*)getJumpTableEntryAddress(MR.getJumpTableIndex());
+ }
+
+ MR.setResultPointer(ResultPtr);
+ }
+
+ // if we are managing the GOT and the relocation wants an index,
+ // give it one
+ if (MR.isGOTRelative() && MemMgr->isManagingGOT()) {
+ unsigned idx = Resolver.getGOTIndexForAddr(ResultPtr);
+ MR.setGOTIndex(idx);
+ if (((void**)MemMgr->getGOTBase())[idx] != ResultPtr) {
+ DEBUG(errs() << "JIT: GOT was out of date for " << ResultPtr
+ << " pointing at " << ((void**)MemMgr->getGOTBase())[idx]
+ << "\n");
+ ((void**)MemMgr->getGOTBase())[idx] = ResultPtr;
+ }
+ }
+ }
+
+ CurFn = 0;
+ TheJIT->getJITInfo().relocate(BufferBegin, &Relocations[0],
+ Relocations.size(), MemMgr->getGOTBase());
+ }
+
+ // Update the GOT entry for F to point to the new code.
+ if (MemMgr->isManagingGOT()) {
+ unsigned idx = Resolver.getGOTIndexForAddr((void*)BufferBegin);
+ if (((void**)MemMgr->getGOTBase())[idx] != (void*)BufferBegin) {
+ DEBUG(errs() << "JIT: GOT was out of date for " << (void*)BufferBegin
+ << " pointing at " << ((void**)MemMgr->getGOTBase())[idx]
+ << "\n");
+ ((void**)MemMgr->getGOTBase())[idx] = (void*)BufferBegin;
+ }
+ }
+
+ // CurBufferPtr may have moved beyond FnEnd, due to memory allocation for
+ // global variables that were referenced in the relocations.
+ MemMgr->endFunctionBody(F.getFunction(), BufferBegin, CurBufferPtr);
+
+ if (CurBufferPtr == BufferEnd) {
+ retryWithMoreMemory(F);
+ return true;
+ } else {
+ // Now that we've succeeded in emitting the function, reset the
+ // SizeEstimate back down to zero.
+ SizeEstimate = 0;
+ }
+
+ BufferBegin = CurBufferPtr = 0;
+ NumBytes += FnEnd-FnStart;
+
+ // Invalidate the icache if necessary.
+ sys::Memory::InvalidateInstructionCache(FnStart, FnEnd-FnStart);
+
+ TheJIT->NotifyFunctionEmitted(*F.getFunction(), FnStart, FnEnd-FnStart,
+ EmissionDetails);
+
+ DEBUG(errs() << "JIT: Finished CodeGen of [" << (void*)FnStart
+ << "] Function: " << F.getFunction()->getName()
+ << ": " << (FnEnd-FnStart) << " bytes of text, "
+ << Relocations.size() << " relocations\n");
+
+ Relocations.clear();
+ ConstPoolAddresses.clear();
+
+ // Mark code region readable and executable if it's not so already.
+ MemMgr->setMemoryExecutable();
+
+ DEBUG(
+ if (sys::hasDisassembler()) {
+ errs() << "JIT: Disassembled code:\n";
+ errs() << sys::disassembleBuffer(FnStart, FnEnd-FnStart,
+ (uintptr_t)FnStart);
+ } else {
+ errs() << "JIT: Binary code:\n";
+ uint8_t* q = FnStart;
+ for (int i = 0; q < FnEnd; q += 4, ++i) {
+ if (i == 4)
+ i = 0;
+ if (i == 0)
+ errs() << "JIT: " << (long)(q - FnStart) << ": ";
+ bool Done = false;
+ for (int j = 3; j >= 0; --j) {
+ if (q + j >= FnEnd)
+ Done = true;
+ else
+ errs() << (unsigned short)q[j];
+ }
+ if (Done)
+ break;
+ errs() << ' ';
+ if (i == 3)
+ errs() << '\n';
+ }
+ errs()<< '\n';
+ }
+ );
+
+ if (DwarfExceptionHandling || JITEmitDebugInfo) {
+ uintptr_t ActualSize = 0;
+ SavedBufferBegin = BufferBegin;
+ SavedBufferEnd = BufferEnd;
+ SavedCurBufferPtr = CurBufferPtr;
+
+ if (MemMgr->NeedsExactSize()) {
+ ActualSize = DE->GetDwarfTableSizeInBytes(F, *this, FnStart, FnEnd);
+ }
+
+ BufferBegin = CurBufferPtr = MemMgr->startExceptionTable(F.getFunction(),
+ ActualSize);
+ BufferEnd = BufferBegin+ActualSize;
+ uint8_t *EhStart;
+ uint8_t *FrameRegister = DE->EmitDwarfTable(F, *this, FnStart, FnEnd,
+ EhStart);
+ MemMgr->endExceptionTable(F.getFunction(), BufferBegin, CurBufferPtr,
+ FrameRegister);
+ uint8_t *EhEnd = CurBufferPtr;
+ BufferBegin = SavedBufferBegin;
+ BufferEnd = SavedBufferEnd;
+ CurBufferPtr = SavedCurBufferPtr;
+
+ if (DwarfExceptionHandling) {
+ TheJIT->RegisterTable(FrameRegister);
+ }
+
+ if (JITEmitDebugInfo) {
+ DebugInfo I;
+ I.FnStart = FnStart;
+ I.FnEnd = FnEnd;
+ I.EhStart = EhStart;
+ I.EhEnd = EhEnd;
+ DR->RegisterFunction(F.getFunction(), I);
+ }
+ }
+
+ if (MMI)
+ MMI->EndFunction();
+
+ return false;
+}
+
+void JITEmitter::retryWithMoreMemory(MachineFunction &F) {
+ DEBUG(errs() << "JIT: Ran out of space for native code. Reattempting.\n");
+ Relocations.clear(); // Clear the old relocations or we'll reapply them.
+ ConstPoolAddresses.clear();
+ ++NumRetries;
+ deallocateMemForFunction(F.getFunction());
+ // Try again with at least twice as much free space.
+ SizeEstimate = (uintptr_t)(2 * (BufferEnd - BufferBegin));
}
-void Emitter::startFunctionStub(const Function &F, unsigned StubSize) {
- SavedCurBlock = CurBlock; SavedCurByte = CurByte;
- CurByte = CurBlock = MemMgr.allocateStub(StubSize);
+/// deallocateMemForFunction - Deallocate all memory for the specified
+/// function body. Also drop any references the function has to stubs.
+void JITEmitter::deallocateMemForFunction(const Function *F) {
+ MemMgr->deallocateMemForFunction(F);
+
+ // TODO: Do we need to unregister exception handling information from libgcc
+ // here?
+
+ if (JITEmitDebugInfo) {
+ DR->UnregisterFunction(F);
+ }
+
+ // If the function did not reference any stubs, return.
+ if (CurFnStubUses.find(F) == CurFnStubUses.end())
+ return;
+
+ // For each referenced stub, erase the reference to this function, and then
+ // erase the list of referenced stubs.
+ SmallVectorImpl<void *> &StubList = CurFnStubUses[F];
+ for (unsigned i = 0, e = StubList.size(); i != e; ++i) {
+ void *Stub = StubList[i];
+
+ // If we already invalidated this stub for this function, continue.
+ if (StubFnRefs.count(Stub) == 0)
+ continue;
+
+ SmallPtrSet<const Function *, 1> &FnRefs = StubFnRefs[Stub];
+ FnRefs.erase(F);
+
+ // If this function was the last reference to the stub, invalidate the stub
+ // in the JITResolver. Were there a memory manager deallocateStub routine,
+ // we could call that at this point too.
+ if (FnRefs.empty()) {
+ DEBUG(errs() << "\nJIT: Invalidated Stub at [" << Stub << "]\n");
+ StubFnRefs.erase(Stub);
+
+ // Invalidate the stub. If it is a GV stub, update the JIT's global
+ // mapping for that GV to zero, otherwise, search the string map of
+ // external function names to stubs and remove the entry for this stub.
+ GlobalValue *GV = Resolver.invalidateStub(Stub);
+ if (GV) {
+ TheJIT->updateGlobalMapping(GV, 0);
+ } else {
+ for (StringMapIterator<void*> i = ExtFnStubs.begin(),
+ e = ExtFnStubs.end(); i != e; ++i) {
+ if (i->second == Stub) {
+ ExtFnStubs.erase(i);
+ break;
+ }
+ }
+ }
+ }
+ }
+ CurFnStubUses.erase(F);
}
-void *Emitter::finishFunctionStub(const Function &F) {
- NumBytes += CurByte-CurBlock;
- DEBUG(std::cerr << "Finished CodeGen of [0x" << std::hex
- << (unsigned)(intptr_t)CurBlock
- << std::dec << "] Function stub for: " << F.getName()
- << ": " << CurByte-CurBlock << " bytes of text\n");
- std::swap(CurBlock, SavedCurBlock);
- CurByte = SavedCurByte;
- return SavedCurBlock;
+
+void* JITEmitter::allocateSpace(uintptr_t Size, unsigned Alignment) {
+ if (BufferBegin)
+ return JITCodeEmitter::allocateSpace(Size, Alignment);
+
+ // create a new memory block if there is no active one.
+ // care must be taken so that BufferBegin is invalidated when a
+ // block is trimmed
+ BufferBegin = CurBufferPtr = MemMgr->allocateSpace(Size, Alignment);
+ BufferEnd = BufferBegin+Size;
+ return CurBufferPtr;
}
-void Emitter::emitByte(unsigned char B) {
- *CurByte++ = B; // Write the byte to memory
+void* JITEmitter::allocateGlobal(uintptr_t Size, unsigned Alignment) {
+ // Delegate this call through the memory manager.
+ return MemMgr->allocateGlobal(Size, Alignment);
}
-void Emitter::emitWord(unsigned W) {
- // This won't work if the endianness of the host and target don't agree! (For
- // a JIT this can't happen though. :)
- *(unsigned*)CurByte = W;
- CurByte += sizeof(unsigned);
+void JITEmitter::emitConstantPool(MachineConstantPool *MCP) {
+ if (TheJIT->getJITInfo().hasCustomConstantPool())
+ return;
+
+ const std::vector<MachineConstantPoolEntry> &Constants = MCP->getConstants();
+ if (Constants.empty()) return;
+
+ unsigned Size = GetConstantPoolSizeInBytes(MCP, TheJIT->getTargetData());
+ unsigned Align = MCP->getConstantPoolAlignment();
+ ConstantPoolBase = allocateSpace(Size, Align);
+ ConstantPool = MCP;
+
+ if (ConstantPoolBase == 0) return; // Buffer overflow.
+
+ DEBUG(errs() << "JIT: Emitted constant pool at [" << ConstantPoolBase
+ << "] (size: " << Size << ", alignment: " << Align << ")\n");
+
+ // Initialize the memory for all of the constant pool entries.
+ unsigned Offset = 0;
+ for (unsigned i = 0, e = Constants.size(); i != e; ++i) {
+ MachineConstantPoolEntry CPE = Constants[i];
+ unsigned AlignMask = CPE.getAlignment() - 1;
+ Offset = (Offset + AlignMask) & ~AlignMask;
+
+ uintptr_t CAddr = (uintptr_t)ConstantPoolBase + Offset;
+ ConstPoolAddresses.push_back(CAddr);
+ if (CPE.isMachineConstantPoolEntry()) {
+ // FIXME: add support to lower machine constant pool values into bytes!
+ llvm_report_error("Initialize memory with machine specific constant pool"
+ "entry has not been implemented!");
+ }
+ TheJIT->InitializeMemory(CPE.Val.ConstVal, (void*)CAddr);
+ DEBUG(errs() << "JIT: CP" << i << " at [0x";
+ errs().write_hex(CAddr) << "]\n");
+
+ const Type *Ty = CPE.Val.ConstVal->getType();
+ Offset += TheJIT->getTargetData()->getTypeAllocSize(Ty);
+ }
}
-void Emitter::emitWordAt(unsigned W, unsigned *Ptr) {
- *Ptr = W;
+void JITEmitter::initJumpTableInfo(MachineJumpTableInfo *MJTI) {
+ if (TheJIT->getJITInfo().hasCustomJumpTables())
+ return;
+
+ const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
+ if (JT.empty()) return;
+
+ unsigned NumEntries = 0;
+ for (unsigned i = 0, e = JT.size(); i != e; ++i)
+ NumEntries += JT[i].MBBs.size();
+
+ unsigned EntrySize = MJTI->getEntrySize();
+
+ // Just allocate space for all the jump tables now. We will fix up the actual
+ // MBB entries in the tables after we emit the code for each block, since then
+ // we will know the final locations of the MBBs in memory.
+ JumpTable = MJTI;
+ JumpTableBase = allocateSpace(NumEntries * EntrySize, MJTI->getAlignment());
}
-uint64_t Emitter::getGlobalValueAddress(GlobalValue *V) {
- // Try looking up the function to see if it is already compiled, if not return
- // 0.
- if (isa<Function>(V))
- return (intptr_t)TheJIT->getPointerToGlobalIfAvailable(V);
- else {
- return (intptr_t)TheJIT->getOrEmitGlobalVariable(cast<GlobalVariable>(V));
+void JITEmitter::emitJumpTableInfo(MachineJumpTableInfo *MJTI) {
+ if (TheJIT->getJITInfo().hasCustomJumpTables())
+ return;
+
+ const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
+ if (JT.empty() || JumpTableBase == 0) return;
+
+ if (TargetMachine::getRelocationModel() == Reloc::PIC_) {
+ assert(MJTI->getEntrySize() == 4 && "Cross JIT'ing?");
+ // For each jump table, place the offset from the beginning of the table
+ // to the target address.
+ int *SlotPtr = (int*)JumpTableBase;
+
+ for (unsigned i = 0, e = JT.size(); i != e; ++i) {
+ const std::vector<MachineBasicBlock*> &MBBs = JT[i].MBBs;
+ // Store the offset of the basic block for this jump table slot in the
+ // memory we allocated for the jump table in 'initJumpTableInfo'
+ uintptr_t Base = (uintptr_t)SlotPtr;
+ for (unsigned mi = 0, me = MBBs.size(); mi != me; ++mi) {
+ uintptr_t MBBAddr = getMachineBasicBlockAddress(MBBs[mi]);
+ *SlotPtr++ = TheJIT->getJITInfo().getPICJumpTableEntry(MBBAddr, Base);
+ }
+ }
+ } else {
+ assert(MJTI->getEntrySize() == sizeof(void*) && "Cross JIT'ing?");
+
+ // For each jump table, map each target in the jump table to the address of
+ // an emitted MachineBasicBlock.
+ intptr_t *SlotPtr = (intptr_t*)JumpTableBase;
+
+ for (unsigned i = 0, e = JT.size(); i != e; ++i) {
+ const std::vector<MachineBasicBlock*> &MBBs = JT[i].MBBs;
+ // Store the address of the basic block for this jump table slot in the
+ // memory we allocated for the jump table in 'initJumpTableInfo'
+ for (unsigned mi = 0, me = MBBs.size(); mi != me; ++mi)
+ *SlotPtr++ = getMachineBasicBlockAddress(MBBs[mi]);
+ }
}
}
-uint64_t Emitter::getGlobalValueAddress(const std::string &Name) {
- return (intptr_t)TheJIT->getPointerToNamedFunction(Name);
+
+void JITEmitter::startGVStub(const GlobalValue* GV, unsigned StubSize,
+ unsigned Alignment) {
+ SavedBufferBegin = BufferBegin;
+ SavedBufferEnd = BufferEnd;
+ SavedCurBufferPtr = CurBufferPtr;
+
+ BufferBegin = CurBufferPtr = MemMgr->allocateStub(GV, StubSize, Alignment);
+ BufferEnd = BufferBegin+StubSize+1;
+}
+
+void JITEmitter::startGVStub(const GlobalValue* GV, void *Buffer,
+ unsigned StubSize) {
+ SavedBufferBegin = BufferBegin;
+ SavedBufferEnd = BufferEnd;
+ SavedCurBufferPtr = CurBufferPtr;
+
+ BufferBegin = CurBufferPtr = (uint8_t *)Buffer;
+ BufferEnd = BufferBegin+StubSize+1;
+}
+
+void *JITEmitter::finishGVStub(const GlobalValue* GV) {
+ NumBytes += getCurrentPCOffset();
+ std::swap(SavedBufferBegin, BufferBegin);
+ BufferEnd = SavedBufferEnd;
+ CurBufferPtr = SavedCurBufferPtr;
+ return SavedBufferBegin;
}
// getConstantPoolEntryAddress - Return the address of the 'ConstantNum' entry
// in the constant pool that was last emitted with the 'emitConstantPool'
// method.
//
-uint64_t Emitter::getConstantPoolEntryAddress(unsigned ConstantNum) {
- assert(ConstantNum < ConstantPoolAddresses.size() &&
- "Invalid ConstantPoolIndex!");
- return (intptr_t)ConstantPoolAddresses[ConstantNum];
+uintptr_t JITEmitter::getConstantPoolEntryAddress(unsigned ConstantNum) const {
+ assert(ConstantNum < ConstantPool->getConstants().size() &&
+ "Invalid ConstantPoolIndex!");
+ return ConstPoolAddresses[ConstantNum];
}
-// getCurrentPCValue - This returns the address that the next emitted byte
-// will be output to.
+// getJumpTableEntryAddress - Return the address of the JumpTable with index
+// 'Index' in the jumpp table that was last initialized with 'initJumpTableInfo'
//
-uint64_t Emitter::getCurrentPCValue() {
- return (intptr_t)CurByte;
+uintptr_t JITEmitter::getJumpTableEntryAddress(unsigned Index) const {
+ const std::vector<MachineJumpTableEntry> &JT = JumpTable->getJumpTables();
+ assert(Index < JT.size() && "Invalid jump table index!");
+
+ unsigned Offset = 0;
+ unsigned EntrySize = JumpTable->getEntrySize();
+
+ for (unsigned i = 0; i < Index; ++i)
+ Offset += JT[i].MBBs.size();
+
+ Offset *= EntrySize;
+
+ return (uintptr_t)((char *)JumpTableBase + Offset);
}
-uint64_t Emitter::forceCompilationOf(Function *F) {
- return (intptr_t)TheJIT->getPointerToFunction(F);
+//===----------------------------------------------------------------------===//
+// Public interface to this file
+//===----------------------------------------------------------------------===//
+
+JITCodeEmitter *JIT::createEmitter(JIT &jit, JITMemoryManager *JMM,
+ TargetMachine &tm) {
+ return new JITEmitter(jit, JMM, tm);
}
// getPointerToNamedFunction - This function is used as a global wrapper to
// resolve their addresses at runtime, and this is the way to do it.
extern "C" {
void *getPointerToNamedFunction(const char *Name) {
- Module &M = TheJIT->getModule();
- if (Function *F = M.getNamedFunction(Name))
+ if (Function *F = TheJIT->FindFunctionNamed(Name))
return TheJIT->getPointerToFunction(F);
return TheJIT->getPointerToNamedFunction(Name);
}
}
+
+// getPointerToFunctionOrStub - If the specified function has been
+// code-gen'd, return a pointer to the function. If not, compile it, or use
+// a stub to implement lazy compilation if available.
+//
+void *JIT::getPointerToFunctionOrStub(Function *F) {
+ // If we have already code generated the function, just return the address.
+ if (void *Addr = getPointerToGlobalIfAvailable(F))
+ return Addr;
+
+ // Get a stub if the target supports it.
+ assert(isa<JITEmitter>(JCE) && "Unexpected MCE?");
+ JITEmitter *JE = cast<JITEmitter>(getCodeEmitter());
+ return JE->getJITResolver().getFunctionStub(F);
+}
+
+void JIT::updateFunctionStub(Function *F) {
+ // Get the empty stub we generated earlier.
+ assert(isa<JITEmitter>(JCE) && "Unexpected MCE?");
+ JITEmitter *JE = cast<JITEmitter>(getCodeEmitter());
+ void *Stub = JE->getJITResolver().getFunctionStub(F);
+
+ // Tell the target jit info to rewrite the stub at the specified address,
+ // rather than creating a new one.
+ void *Addr = getPointerToGlobalIfAvailable(F);
+ getJITInfo().emitFunctionStubAtAddr(F, Addr, Stub, *getCodeEmitter());
+}
+
+/// updateDlsymStubTable - Emit the data necessary to relocate the stubs
+/// that were emitted during code generation.
+///
+void JIT::updateDlsymStubTable() {
+ assert(isa<JITEmitter>(JCE) && "Unexpected MCE?");
+ JITEmitter *JE = cast<JITEmitter>(getCodeEmitter());
+
+ SmallVector<GlobalValue*, 8> GVs;
+ SmallVector<void*, 8> Ptrs;
+ const StringMap<void *> &ExtFns = JE->getExternalFnStubs();
+
+ JE->getJITResolver().getRelocatableGVs(GVs, Ptrs);
+
+ unsigned nStubs = GVs.size() + ExtFns.size();
+
+ // If there are no relocatable stubs, return.
+ if (nStubs == 0)
+ return;
+
+ // If there are no new relocatable stubs, return.
+ void *CurTable = JE->getMemMgr()->getDlsymTable();
+ if (CurTable && (*(unsigned *)CurTable == nStubs))
+ return;
+
+ // Calculate the size of the stub info
+ unsigned offset = 4 + 4 * nStubs + sizeof(intptr_t) * nStubs;
+
+ SmallVector<unsigned, 8> Offsets;
+ for (unsigned i = 0; i != GVs.size(); ++i) {
+ Offsets.push_back(offset);
+ offset += GVs[i]->getName().size() + 1;
+ }
+ for (StringMapConstIterator<void*> i = ExtFns.begin(), e = ExtFns.end();
+ i != e; ++i) {
+ Offsets.push_back(offset);
+ offset += strlen(i->first()) + 1;
+ }
+
+ // Allocate space for the new "stub", which contains the dlsym table.
+ JE->startGVStub(0, offset, 4);
+
+ // Emit the number of records
+ JE->emitInt32(nStubs);
+
+ // Emit the string offsets
+ for (unsigned i = 0; i != nStubs; ++i)
+ JE->emitInt32(Offsets[i]);
+
+ // Emit the pointers. Verify that they are at least 2-byte aligned, and set
+ // the low bit to 0 == GV, 1 == Function, so that the client code doing the
+ // relocation can write the relocated pointer at the appropriate place in
+ // the stub.
+ for (unsigned i = 0; i != GVs.size(); ++i) {
+ intptr_t Ptr = (intptr_t)Ptrs[i];
+ assert((Ptr & 1) == 0 && "Stub pointers must be at least 2-byte aligned!");
+
+ if (isa<Function>(GVs[i]))
+ Ptr |= (intptr_t)1;
+
+ if (sizeof(Ptr) == 8)
+ JE->emitInt64(Ptr);
+ else
+ JE->emitInt32(Ptr);
+ }
+ for (StringMapConstIterator<void*> i = ExtFns.begin(), e = ExtFns.end();
+ i != e; ++i) {
+ intptr_t Ptr = (intptr_t)i->second | 1;
+
+ if (sizeof(Ptr) == 8)
+ JE->emitInt64(Ptr);
+ else
+ JE->emitInt32(Ptr);
+ }
+
+ // Emit the strings.
+ for (unsigned i = 0; i != GVs.size(); ++i)
+ JE->emitString(GVs[i]->getName());
+ for (StringMapConstIterator<void*> i = ExtFns.begin(), e = ExtFns.end();
+ i != e; ++i)
+ JE->emitString(i->first());
+
+ // Tell the JIT memory manager where it is. The JIT Memory Manager will
+ // deallocate space for the old one, if one existed.
+ JE->getMemMgr()->SetDlsymTable(JE->finishGVStub(0));
+}
+
+/// freeMachineCodeForFunction - release machine code memory for given Function.
+///
+void JIT::freeMachineCodeForFunction(Function *F) {
+
+ // Delete translation for this from the ExecutionEngine, so it will get
+ // retranslated next time it is used.
+ void *OldPtr = updateGlobalMapping(F, 0);
+
+ if (OldPtr)
+ TheJIT->NotifyFreeingMachineCode(*F, OldPtr);
+
+ // Free the actual memory for the function body and related stuff.
+ assert(isa<JITEmitter>(JCE) && "Unexpected MCE?");
+ cast<JITEmitter>(JCE)->deallocateMemForFunction(F);
+}
projects / oota-llvm.git / blobdiff