replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Move target specific code to target files. The new MachineCodeEmitter 

class is actually target independent!

llvm-svn: 6517
This commit is contained in:
Chris Lattner 2003-06-01 23:24:36 +00:00
parent 3bb2a00849
commit 6b689e3ad4
5 changed files with 76 additions and 171 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

82
llvm/lib/ExecutionEngine/JIT/Callback.cpp
View File

@ -1,82 +0,0 @@
//===-- Callback.cpp - Trap handler for function resolution ---------------===//
//
// This file defines the handler which is invoked when a reference to a
// non-codegen'd function is found. This file defines target specific code
// which is used by the JIT.
//
//===----------------------------------------------------------------------===//
#include "VM.h"
#include "Support/Statistic.h"
#include "llvm/CodeGen/MachineCodeEmitter.h"
#include <iostream>
static VM *TheVM = 0;
// CompilationCallback - Invoked the first time that a call site is found,
// which causes lazy compilation of the target function.
//
void VM::CompilationCallback() {
#if defined(i386) || defined(__i386__) || defined(__x86__)
unsigned *StackPtr = (unsigned*)__builtin_frame_address(0);
unsigned RetAddr = (unsigned)__builtin_return_address(0);
assert(StackPtr[1] == RetAddr &&
"Could not find return address on the stack!");
bool isStub = ((unsigned char*)RetAddr)[0] == 0xCD; // Interrupt marker?
// The call instruction should have pushed the return value onto the stack...
RetAddr -= 4; // Backtrack to the reference itself...
DEBUG(std::cerr << "In callback! Addr=0x" << std::hex << RetAddr
<< " ESP=0x" << (unsigned)StackPtr << std::dec
<< ": Resolving call to function: "
<< TheVM->getFunctionReferencedName((void*)RetAddr) << "\n");
// Sanity check to make sure this really is a call instruction...
assert(((unsigned char*)RetAddr)[-1] == 0xE8 && "Not a call instr!");
unsigned NewVal = (unsigned)TheVM->resolveFunctionReference((void*)RetAddr);
// Rewrite the call target... so that we don't fault every time we execute
// the call.
*(unsigned*)RetAddr = NewVal-RetAddr-4;
if (isStub) {
// If this is a stub, rewrite the call into an unconditional branch
// instruction so that two return addresses are not pushed onto the stack
// when the requested function finally gets called. This also makes the
// 0xCD byte (interrupt) dead, so the marker doesn't effect anything.
((unsigned char*)RetAddr)[-1] = 0xE9;
}
// Change the return address to reexecute the call instruction...
StackPtr[1] -= 5;
#else
abort();
#endif
}
/// emitStubForFunction - This virtual method is used by the JIT when it needs
/// to emit the address of a function for a function whose code has not yet
/// been generated. In order to do this, it generates a stub which jumps to
/// the lazy function compiler, which will eventually get fixed to call the
/// function directly.
///
void *VM::emitStubForFunction(const Function &F) {
#if defined(i386) || defined(__i386__) || defined(__x86__)
MCE->startFunctionStub(F, 6);
MCE->emitByte(0xE8); // Call with 32 bit pc-rel destination...
MCE->emitGlobalAddress((GlobalValue*)&F, true);
MCE->emitByte(0xCD); // Interrupt - Just a marker identifying the stub!
return MCE->finishFunctionStub(F);
#else
abort();
#endif
}
void VM::registerCallback() {
TheVM = this;
}

108
llvm/lib/ExecutionEngine/JIT/Emitter.cpp
View File

@ -13,38 +13,45 @@
#include "llvm/Function.h"
#include "Support/Statistic.h"
static VM *TheVM = 0;
namespace {
Statistic<> NumBytes("jello", "Number of bytes of machine code compiled");
class Emitter : public MachineCodeEmitter {
VM &TheVM;
// CurBlock - The start of the current block of memory. CurByte - The
// current byte being emitted to.
unsigned char *CurBlock, *CurByte;
// When outputting a function stub in the context of some other function, we
// save CurBlock and CurByte here.
unsigned char *SavedCurBlock, *SavedCurByte;
std::vector<std::pair<BasicBlock*, unsigned *> > BBRefs;
std::map<BasicBlock*, unsigned> BBLocations;
// ConstantPoolAddresses - Contains the location for each entry in the
// constant pool.
std::vector<void*> ConstantPoolAddresses;
public:
Emitter(VM &vm) : TheVM(vm) {}
Emitter(VM &vm) { TheVM = &vm; }
virtual void startFunction(MachineFunction &F);
virtual void finishFunction(MachineFunction &F);
virtual void emitConstantPool(MachineConstantPool *MCP);
virtual void startBasicBlock(MachineBasicBlock &BB);
virtual void startFunctionStub(const Function &F, unsigned StubSize);
virtual void* finishFunctionStub(const Function &F);
virtual void emitByte(unsigned char B);
virtual void emitPCRelativeDisp(Value *V);
virtual void emitGlobalAddress(GlobalValue *V, bool isPCRelative);
virtual void emitGlobalAddress(const std::string &Name, bool isPCRelative);
virtual void emitFunctionConstantValueAddress(unsigned ConstantNum,
int Offset);
private:
void emitAddress(void *Addr, bool isPCRelative);
virtual void emitWord(unsigned W);
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);
};
}
@ -66,21 +73,13 @@ static void *getMemory(unsigned NumPages) {
void Emitter::startFunction(MachineFunction &F) {
CurBlock = (unsigned char *)getMemory(8);
CurBlock = (unsigned char *)getMemory(16);
CurByte = CurBlock; // Start writing at the beginning of the fn.
TheVM.addGlobalMapping(F.getFunction(), CurBlock);
TheVM->addGlobalMapping(F.getFunction(), CurBlock);
}
void Emitter::finishFunction(MachineFunction &F) {
ConstantPoolAddresses.clear();
for (unsigned i = 0, e = BBRefs.size(); i != e; ++i) {
unsigned Location = BBLocations[BBRefs[i].first];
unsigned *Ref = BBRefs[i].second;
*Ref = Location-(unsigned)(intptr_t)Ref-4;
}
BBRefs.clear();
BBLocations.clear();
NumBytes += CurByte-CurBlock;
DEBUG(std::cerr << "Finished CodeGen of [0x" << std::hex
@ -95,18 +94,12 @@ void Emitter::emitConstantPool(MachineConstantPool *MCP) {
// For now we just allocate some memory on the heap, this can be
// dramatically improved.
const Type *Ty = ((Value*)Constants[i])->getType();
void *Addr = malloc(TheVM.getTargetData().getTypeSize(Ty));
TheVM.InitializeMemory(Constants[i], Addr);
void *Addr = malloc(TheVM->getTargetData().getTypeSize(Ty));
TheVM->InitializeMemory(Constants[i], Addr);
ConstantPoolAddresses.push_back(Addr);
}
}
void Emitter::startBasicBlock(MachineBasicBlock &BB) {
BBLocations[BB.getBasicBlock()] = (unsigned)(intptr_t)CurByte;
}
void Emitter::startFunctionStub(const Function &F, unsigned StubSize) {
SavedCurBlock = CurBlock; SavedCurByte = CurByte;
// FIXME: this is a huge waste of memory.
@ -129,6 +122,46 @@ void Emitter::emitByte(unsigned char B) {
*CurByte++ = B; // Write the byte to memory
}
void Emitter::emitWord(unsigned W) {
// FIXME: 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);
}
uint64_t Emitter::getGlobalValueAddress(GlobalValue *V) {
// Try looking up the function to see if it is already compiled, if not return
// 0.
return (intptr_t)TheVM->getPointerToGlobalIfAvailable(V);
}
uint64_t Emitter::getGlobalValueAddress(const std::string &Name) {
return (intptr_t)TheVM->getPointerToNamedFunction(Name);
}
// 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];
}
// getCurrentPCValue - This returns the address that the next emitted byte
// will be output to.
//
uint64_t Emitter::getCurrentPCValue() {
return (intptr_t)CurByte;
}
uint64_t Emitter::forceCompilationOf(Function *F) {
return (intptr_t)TheVM->getPointerToFunction(F);
}
#if 0
// emitPCRelativeDisp - For functions, just output a displacement that will
// cause a reference to the zero page, which will cause a seg-fault, causing
@ -157,23 +190,19 @@ void Emitter::emitAddress(void *Addr, bool isPCRelative) {
void Emitter::emitGlobalAddress(GlobalValue *V, bool isPCRelative) {
if (isPCRelative) { // must be a call, this is a major hack!
// Try looking up the function to see if it is already compiled!
if (void *Addr = TheVM.getPointerToGlobalIfAvailable(V)) {
if (void *Addr = TheVM->getPointerToGlobalIfAvailable(V)) {
emitAddress(Addr, isPCRelative);
} else { // Function has not yet been code generated!
TheVM.addFunctionRef(CurByte, cast<Function>(V));
TheVM->addFunctionRef(CurByte, cast<Function>(V));
// Delayed resolution...
emitAddress((void*)VM::CompilationCallback, isPCRelative);
}
} else {
emitAddress(TheVM.getPointerToGlobal(V), isPCRelative);
emitAddress(TheVM->getPointerToGlobal(V), isPCRelative);
}
}
void Emitter::emitGlobalAddress(const std::string &Name, bool isPCRelative) {
emitAddress(TheVM.getPointerToNamedFunction(Name), isPCRelative);
}
void Emitter::emitFunctionConstantValueAddress(unsigned ConstantNum,
int Offset) {
assert(ConstantNum < ConstantPoolAddresses.size() &&
@ -181,3 +210,4 @@ void Emitter::emitFunctionConstantValueAddress(unsigned ConstantNum,
*(void**)CurByte = (char*)ConstantPoolAddresses[ConstantNum]+Offset;
CurByte += 4;
}
#endif

5
llvm/lib/ExecutionEngine/JIT/JIT.cpp
View File

@ -43,7 +43,7 @@ ExecutionEngine *ExecutionEngine::createJIT(Module *M, unsigned Config) {
if (Arch == "x86") {
TargetMachineAllocator = allocateX86TargetMachine;
} else if (Arch == "sparc") {
TargetMachineAllocator = allocateSparcTargetMachine;
//TargetMachineAllocator = allocateSparcTargetMachine;
}
if (TargetMachineAllocator) {
@ -65,11 +65,10 @@ VM::VM(Module *M, TargetMachine *tm) : ExecutionEngine(M), TM(*tm) {
if (Arch == "x86") {
MCE = createX86Emitter(*this);
} else if (Arch == "sparc") {
MCE = createSparcEmitter(*this);
//MCE = createSparcEmitter(*this);
}
setupPassManager();
registerCallback();
emitGlobals();
}

23
llvm/lib/ExecutionEngine/JIT/VM.cpp
View File

@ -36,22 +36,6 @@ void VM::setupPassManager() {
}
}
void *VM::resolveFunctionReference(void *RefAddr) {
Function *F = FunctionRefs[RefAddr];
assert(F && "Reference address not known!");
void *Addr = getPointerToFunction(F);
assert(Addr && "Pointer to function unknown!");
FunctionRefs.erase(RefAddr);
return Addr;
}
const std::string &VM::getFunctionReferencedName(void *RefAddr) {
assert(FunctionRefs[RefAddr] && "Function address unknown!");
return FunctionRefs[RefAddr]->getName();
}
/// getPointerToFunction - This method is used to get the address of the
/// specified function, compiling it if neccesary.
///
@ -63,12 +47,7 @@ void *VM::getPointerToFunction(const Function *F) {
return Addr = getPointerToNamedFunction(F->getName());
static bool isAlreadyCodeGenerating = false;
if (isAlreadyCodeGenerating) {
// Generate a function stub instead of reentering...
void *SAddr = emitStubForFunction(*F);
assert(SAddr && "Target machine doesn't support function stub generation!");
return SAddr;
}
assert(!isAlreadyCodeGenerating && "ERROR: RECURSIVE COMPILATION DETECTED!");
// FIXME: JIT all of the functions in the module. Eventually this will JIT
// functions on demand. This has the effect of populating all of the

29
llvm/lib/ExecutionEngine/JIT/VM.h
View File

@ -22,12 +22,6 @@ class VM : public ExecutionEngine {
PassManager PM; // Passes to compile a function
MachineCodeEmitter *MCE; // MCE object
// FunctionRefs - A mapping between addresses that refer to unresolved
// functions and the LLVM function object itself. This is used by the fault
// handler to lazily patch up references...
//
std::map<void*, Function*> FunctionRefs;
public:
VM(Module *M, TargetMachine *tm);
~VM();
@ -37,14 +31,6 @@ public:
virtual int run(const std::string &FnName,
const std::vector<std::string> &Args);
void addFunctionRef(void *Ref, Function *F) {
FunctionRefs[Ref] = F;
}
const std::string &getFunctionReferencedName(void *RefAddr);
void *resolveFunctionReference(void *RefAddr);
/// getPointerToNamedFunction - This method returns the address of the
/// specified function by using the dlsym function call. As such it is only
/// useful for resolving library symbols, not code generated symbols.
@ -61,21 +47,14 @@ public:
///
static void runAtExitHandlers();
/// getPointerToFunction - This returns the address of the specified function,
/// compiling it if necessary.
void *getPointerToFunction(const Function *F);
private:
static MachineCodeEmitter *createX86Emitter(VM &V);
static MachineCodeEmitter *createSparcEmitter(VM &V);
void setupPassManager();
void *getPointerToFunction(const Function *F);
void registerCallback();
/// emitStubForFunction - This method is used by the JIT when it needs to emit
/// the address of a function for a function whose code has not yet been
/// generated. In order to do this, it generates a stub which jumps to the
/// lazy function compiler, which will eventually get fixed to call the
/// function directly.
///
void *emitStubForFunction(const Function &F);
};
#endif