-namespace {
- class JITResolver {
- SparcV9CodeEmitter &SparcV9;
- MachineCodeEmitter &MCE;
-
- // LazyCodeGenMap - Keep track of call sites for functions that are to be
- // lazily resolved.
- std::map<uint64_t, Function*> LazyCodeGenMap;
-
- // LazyResolverMap - Keep track of the lazy resolver created for a
- // particular function so that we can reuse them if necessary.
- std::map<Function*, uint64_t> LazyResolverMap;
- public:
- JITResolver(SparcV9CodeEmitter &V9,
- MachineCodeEmitter &mce) : SparcV9(V9), MCE(mce) {}
- uint64_t getLazyResolver(Function *F);
- uint64_t addFunctionReference(uint64_t Address, Function *F);
-
- // Utility functions for accessing data from static callback
- uint64_t getCurrentPCValue() {
- return MCE.getCurrentPCValue();
- }
- unsigned getBinaryCodeForInstr(MachineInstr &MI) {
- 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;
-}
-
-/// addFunctionReference - This method is called when we need to emit the
-/// address of a function that has not yet been emitted, so we don't know the
-/// address. Instead, we emit a call to the CompilationCallback method, and
-/// keep track of where we are.
-///
-uint64_t JITResolver::addFunctionReference(uint64_t Address, Function *F) {
- LazyCodeGenMap[Address] = F;
- return (intptr_t)&JITResolver::CompilationCallback;
-}
-
-uint64_t JITResolver::resolveFunctionReference(uint64_t RetAddr) {
- std::map<uint64_t, Function*>::iterator I = LazyCodeGenMap.find(RetAddr);
- assert(I != LazyCodeGenMap.end() && "Not in map!");
- Function *F = I->second;
- LazyCodeGenMap.erase(I);
- return MCE.forceCompilationOf(F);
-}
-
-uint64_t JITResolver::getLazyResolver(Function *F) {
- std::map<Function*, uint64_t>::iterator I = LazyResolverMap.lower_bound(F);
- if (I != LazyResolverMap.end() && I->first == F) return I->second;
-
-//std::cerr << "Getting lazy resolver for : " << ((Value*)F)->getName() << "\n";
-
- uint64_t Stub = emitStubForFunction(F);
- LazyResolverMap.insert(I, std::make_pair(F, Stub));
- 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 CameFrom = (uint64_t)(intptr_t)__builtin_return_address(0);
- int64_t Target = (int64_t)TheJITResolver->resolveFunctionReference(CameFrom);
- DEBUG(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);
- 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...
- // 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
-/// 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.
-///
-uint64_t JITResolver::emitStubForFunction(Function *F) {
- MCE.startFunctionStub(*F, 6);
-
- DEBUG(std::cerr << "Emitting stub at addr: 0x"
- << std::hex << MCE.getCurrentPCValue() << "\n");
-
- 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;
- 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;
-
- SparcV9.emitWord(0xDEADBEEF); // marker so that we know it's really a stub
- return (intptr_t)MCE.finishFunctionStub(*F);
-}
-
-