Added lazy function resolution to the JIT.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@6633 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Misha Brukman 2003-06-05 20:52:06 +00:00
parent e77d65a8ed
commit f47d9c28d9
2 changed files with 223 additions and 31 deletions

View File

@ -54,10 +54,13 @@ namespace {
return SparcV9.getBinaryCodeForInstr(MI);
}
inline uint64_t insertFarJumpAtAddr(int64_t Value, uint64_t Addr);
private:
uint64_t emitStubForFunction(Function *F);
static void CompilationCallback();
uint64_t resolveFunctionReference(uint64_t RetAddr);
};
JITResolver *TheJITResolver;
@ -92,27 +95,175 @@ uint64_t JITResolver::getLazyResolver(Function *F) {
return Stub;
}
uint64_t JITResolver::insertFarJumpAtAddr(int64_t Target, uint64_t Addr) {
static const unsigned i1 = SparcIntRegClass::i1, i2 = SparcIntRegClass::i2,
i7 = SparcIntRegClass::i7,
o6 = SparcIntRegClass::o6, g0 = SparcIntRegClass::g0;
//
// Save %i1, %i2 to the stack so we can form a 64-bit constant in %i2
//
// stx %i1, [%sp + 2119] ;; save %i1 to the stack, used as temp
MachineInstr *STX = BuildMI(V9::STXi, 3).addReg(i1).addReg(o6).addSImm(2119);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*STX);
delete STX;
Addr += 4;
// stx %i2, [%sp + 2127] ;; save %i2 to the stack
STX = BuildMI(V9::STXi, 3).addReg(i2).addReg(o6).addSImm(2127);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*STX);
delete STX;
Addr += 4;
//
// Get address to branch into %i2, using %i1 as a temporary
//
// sethi %uhi(Target), %i1 ;; get upper 22 bits of Target into %i1
MachineInstr *SH = BuildMI(V9::SETHI, 2).addSImm(Target >> 42).addReg(i1);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*SH);
delete SH;
Addr += 4;
// or %i1, %ulo(Target), %i1 ;; get 10 lower bits of upper word into %1
MachineInstr *OR = BuildMI(V9::ORi, 3)
.addReg(i1).addSImm((Target >> 32) & 0x03ff).addReg(i1);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*OR);
delete OR;
Addr += 4;
// sllx %i1, 32, %i1 ;; shift those 10 bits to the upper word
MachineInstr *SL = BuildMI(V9::SLLXi6, 3).addReg(i1).addSImm(32).addReg(i1);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*SL);
delete SL;
Addr += 4;
// sethi %hi(Target), %i2 ;; extract bits 10-31 into the dest reg
SH = BuildMI(V9::SETHI, 2).addSImm((Target >> 10) & 0x03fffff).addReg(i2);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*SH);
delete SH;
Addr += 4;
// or %i1, %i2, %i2 ;; get upper word (in %i1) into %i2
OR = BuildMI(V9::ORr, 3).addReg(i1).addReg(i2).addReg(i2);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*OR);
delete OR;
Addr += 4;
// or %i2, %lo(Target), %i2 ;; get lowest 10 bits of Target into %i2
OR = BuildMI(V9::ORi, 3).addReg(i2).addSImm(Target & 0x03ff).addReg(i2);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*OR);
delete OR;
Addr += 4;
// ldx [%sp + 2119], %i1 ;; restore %i1 -> 2119 = BIAS(2047) + 72
MachineInstr *LDX = BuildMI(V9::LDXi, 3).addReg(o6).addSImm(2119).addReg(i1);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*LDX);
delete LDX;
Addr += 4;
// jmpl %i2, %g0, %g0 ;; indirect branch on %i2
MachineInstr *J = BuildMI(V9::JMPLRETr, 3).addReg(i2).addReg(g0).addReg(g0);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*J);
delete J;
Addr += 4;
// ldx [%sp + 2127], %i2 ;; restore %i2 -> 2127 = BIAS(2047) + 80
LDX = BuildMI(V9::LDXi, 3).addReg(o6).addSImm(2127).addReg(i2);
*((unsigned*)(intptr_t)Addr) = getBinaryCodeForInstr(*LDX);
delete LDX;
Addr += 4;
return Addr;
}
void JITResolver::CompilationCallback() {
uint64_t *StackPtr = (uint64_t*)__builtin_frame_address(0);
uint64_t RetAddr = (uint64_t)(intptr_t)__builtin_return_address(0);
std::cerr << "In callback! Addr=0x" << std::hex << RetAddr
<< " SP=0x" << (uint64_t)(intptr_t)StackPtr << std::dec << "\n";
int64_t NewVal = (int64_t)TheJITResolver->resolveFunctionReference(RetAddr);
uint64_t CameFrom = (uint64_t)(intptr_t)__builtin_return_address(0);
int64_t Target = (int64_t)TheJITResolver->resolveFunctionReference(CameFrom);
std::cerr << "In callback! Addr=0x" << std::hex << CameFrom << "\n";
// Rewrite the call target... so that we don't fault every time we execute
// the call.
#if 0
int64_t RealCallTarget = (int64_t)
((NewVal - TheJITResolver->getCurrentPCValue()) >> 4);
MachineInstr *MI = BuildMI(V9::CALL, 1);
MI->addSignExtImmOperand(RealCallTarget);
// FIXME: this could be in the wrong byte order!!
*((unsigned*)(intptr_t)RetAddr) = TheJITResolver->getBinaryCodeForInstr(*MI);
if (RealCallTarget >= (1<<22) || RealCallTarget <= -(1<<22)) {
std::cerr << "Address out of bounds for 22bit BA: " << RealCallTarget<<"\n";
abort();
}
#endif
//uint64_t CurrPC = TheJITResolver->getCurrentPCValue();
// we will insert 9 instructions before we do the actual jump
//int64_t NewTarget = (NewVal - 9*4 - InstAddr) >> 2;
static const unsigned i1 = SparcIntRegClass::i1, i2 = SparcIntRegClass::i2,
i7 = SparcIntRegClass::i7, o6 = SparcIntRegClass::o6,
o7 = SparcIntRegClass::o7, g0 = SparcIntRegClass::g0;
// Subtract 4 to overwrite the 'save' that's there now
uint64_t InstAddr = CameFrom-4;
InstAddr = TheJITResolver->insertFarJumpAtAddr(Target, InstAddr);
// CODE SHOULD NEVER GO PAST THIS LOAD!! The real function should return to
// the original caller, not here!!
// FIXME: add call 0 to make sure?!?
// =============== THE REAL STUB ENDS HERE =========================
// What follows below is one-time restore code, because this callback may be
// changing registers in unpredictible ways. However, since it is executed
// only once per function (after the function is resolved, the callback is no
// longer in the path), this has to be done only once.
//
// Thus, it is after the regular stub code. The call back returns to THIS
// point, but every other call to the target function will execute the code
// above. Hence, this code is one-time use.
uint64_t OneTimeRestore = InstAddr;
// restore %g0, 0, %g0
//MachineInstr *R = BuildMI(V9::RESTOREi, 3).addMReg(g0).addSImm(0)
// .addMReg(g0, MOTy::Def);
//*((unsigned*)(intptr_t)InstAddr)=TheJITResolver->getBinaryCodeForInstr(*R);
//delete R;
// FIXME: BuildMI() above crashes. Encode the instruction directly.
// restore %g0, 0, %g0
*((unsigned*)(intptr_t)InstAddr) = 0x81e82000U;
InstAddr += 4;
InstAddr = TheJITResolver->insertFarJumpAtAddr(Target, InstAddr);
// FIXME: if the target function is close enough to fit into the 19bit disp of
// BA, we should use this version, as its much cheaper to generate.
/*
MachineInstr *MI = BuildMI(V9::BA, 1).addSImm(RealCallTarget);
*((unsigned*)(intptr_t)InstAddr) = TheJITResolver->getBinaryCodeForInstr(*MI);
delete MI;
InstAddr += 4;
// Add another NOP
MachineInstr *Nop = BuildMI(V9::NOP, 0);
*((unsigned*)(intptr_t)InstAddr)=TheJITResolver->getBinaryCodeForInstr(*Nop);
delete Nop;
InstAddr += 4;
MachineInstr *BA = BuildMI(V9::BA, 1).addSImm(RealCallTarget-2);
*((unsigned*)(intptr_t)InstAddr) = TheJITResolver->getBinaryCodeForInstr(*BA);
delete BA;
*/
// Change the return address to reexecute the call instruction...
StackPtr[1] -= 4;
// The return address is really %o7, but will disappear after this function
// returns, and the register windows are rotated away.
#if defined(sparc) || defined(__sparc__) || defined(__sparcv9)
__asm__ __volatile__ ("or %%g0, %0, %%i7" : : "r" (OneTimeRestore-8));
#endif
}
/// emitStubForFunction - This method is used by the JIT when it needs to emit
@ -122,26 +273,31 @@ void JITResolver::CompilationCallback() {
/// directly.
///
uint64_t JITResolver::emitStubForFunction(Function *F) {
#if 0
MCE.startFunctionStub(*F, 6);
MCE.emitByte(0xE8); // Call with 32 bit pc-rel destination...
uint64_t Address = addFunctionReference(MCE.getCurrentPCValue(), F);
MCE.emitWord(Address-MCE.getCurrentPCValue()-4);
std::cerr << "Emitting stub at addr: 0x"
<< std::hex << MCE.getCurrentPCValue() << "\n";
MCE.emitByte(0xCD); // Interrupt - Just a marker identifying the stub!
return (intptr_t)MCE.finishFunctionStub(*F);
#endif
MCE.startFunctionStub(*F, 6);
unsigned o6 = SparcIntRegClass::o6;
// save %sp, -192, %sp
MachineInstr *SV = BuildMI(V9::SAVEi, 3).addReg(o6).addSImm(-192).addReg(o6);
SparcV9.emitWord(SparcV9.getBinaryCodeForInstr(*SV));
delete SV;
int64_t CurrPC = MCE.getCurrentPCValue();
int64_t Addr = (int64_t)addFunctionReference(CurrPC, F);
int64_t CallTarget = (Addr-CurrPC) >> 2;
MachineInstr *Call = BuildMI(V9::CALL, 1);
Call->addSignExtImmOperand(CallTarget);
if (CallTarget >= (1 << 30) || CallTarget <= -(1 << 30)) {
std::cerr << "Call target beyond 30 bit limit of CALL: " <<CallTarget<<"\n";
abort();
}
// call CallTarget ;; invoke the callback
MachineInstr *Call = BuildMI(V9::CALL, 1).addSImm(CallTarget);
SparcV9.emitWord(SparcV9.getBinaryCodeForInstr(*Call));
delete Call;
// nop ;; call delay slot
MachineInstr *Nop = BuildMI(V9::NOP, 0);
SparcV9.emitWord(SparcV9.getBinaryCodeForInstr(*Nop));
delete Nop;
@ -170,7 +326,25 @@ void SparcV9CodeEmitter::emitWord(unsigned Val) {
}
}
unsigned getRealRegNum(unsigned fakeReg, unsigned regClass) {
bool SparcV9CodeEmitter::isFPInstr(MachineInstr &MI) {
for (unsigned i = 0, e = MI.getNumOperands(); i < e; ++i) {
const MachineOperand &MO = MI.getOperand(i);
if (MO.isPhysicalRegister()) {
unsigned fakeReg = MO.getReg(), realReg, regClass, regType;
regType = TM.getRegInfo().getRegType(fakeReg);
// At least map fakeReg into its class
fakeReg = TM.getRegInfo().getClassRegNum(fakeReg, regClass);
if (regClass == UltraSparcRegInfo::FPSingleRegType ||
regClass == UltraSparcRegInfo::FPDoubleRegType)
return true;
}
}
return false;
}
unsigned
SparcV9CodeEmitter::getRealRegNum(unsigned fakeReg, unsigned regClass,
MachineInstr &MI) {
switch (regClass) {
case UltraSparcRegInfo::IntRegType: {
// Sparc manual, p31
@ -199,11 +373,23 @@ unsigned getRealRegNum(unsigned fakeReg, unsigned regClass) {
return fakeReg;
}
case UltraSparcRegInfo::FloatCCRegType: {
/* These are laid out %fcc0 - %fcc3 => 0 - 3, so are correct */
return fakeReg;
}
case UltraSparcRegInfo::IntCCRegType: {
return fakeReg;
static const unsigned FPInstrIntCCReg[] = { 6 /* xcc */, 4 /* icc */ };
static const unsigned IntInstrIntCCReg[] = { 2 /* xcc */, 0 /* icc */ };
if (isFPInstr(MI)) {
assert(fakeReg < sizeof(FPInstrIntCCReg)/sizeof(FPInstrIntCCReg[0])
&& "Int CC register out of bounds for FPInstr IntCCReg map");
return FPInstrIntCCReg[fakeReg];
} else {
assert(fakeReg < sizeof(IntInstrIntCCReg)/sizeof(IntInstrIntCCReg[0])
&& "Int CC register out of bounds for IntInstr IntCCReg map");
return IntInstrIntCCReg[fakeReg];
}
}
default:
assert(0 && "Invalid unified register number in getRegType");
@ -278,7 +464,9 @@ int64_t SparcV9CodeEmitter::getMachineOpValue(MachineInstr &MI,
std::cerr << "ERROR: PC relative disp unhandled:" << MO << "\n";
abort();
}
} else if (MO.isPhysicalRegister()) {
} else if (MO.isPhysicalRegister() ||
MO.getType() == MachineOperand::MO_CCRegister)
{
// This is necessary because the Sparc doesn't actually lay out registers
// in the real fashion -- it skips those that it chooses not to allocate,
// i.e. those that are the SP, etc.
@ -287,7 +475,7 @@ int64_t SparcV9CodeEmitter::getMachineOpValue(MachineInstr &MI,
// At least map fakeReg into its class
fakeReg = TM.getRegInfo().getClassRegNum(fakeReg, regClass);
// Find the real register number for use in an instruction
realReg = getRealRegNum(fakeReg, regClass);
realReg = getRealRegNum(fakeReg, regClass, MI);
std::cerr << "Reg[" << std::dec << fakeReg << "] = " << realReg << "\n";
rv = realReg;
} else if (MO.isImmediate()) {
@ -327,13 +515,13 @@ int64_t SparcV9CodeEmitter::getMachineOpValue(MachineInstr &MI,
// are used in SPARC assembly. (Some of these make no sense in combination
// with some of the above; we'll trust that the instruction selector
// will not produce nonsense, and not check for valid combinations here.)
if (MO.opLoBits32()) { // %lo(val)
if (MO.opLoBits32()) { // %lo(val) == %lo() in Sparc ABI doc
return rv & 0x03ff;
} else if (MO.opHiBits32()) { // %lm(val)
} else if (MO.opHiBits32()) { // %lm(val) == %hi() in Sparc ABI doc
return (rv >> 10) & 0x03fffff;
} else if (MO.opLoBits64()) { // %hm(val)
} else if (MO.opLoBits64()) { // %hm(val) == %ulo() in Sparc ABI doc
return (rv >> 32) & 0x03ff;
} else if (MO.opHiBits64()) { // %hh(val)
} else if (MO.opHiBits64()) { // %hh(val) == %uhi() in Sparc ABI doc
return rv >> 42;
} else { // (unadorned) val
return rv;

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@ -47,6 +47,10 @@ private:
void emitBasicBlock(MachineBasicBlock &MBB);
void* getGlobalAddress(GlobalValue *V, MachineInstr &MI,
bool isPCRelative);
bool isFPInstr(MachineInstr &MI);
unsigned getRealRegNum(unsigned fakeReg, unsigned regClass,
MachineInstr &MI);
};
#endif