//===-- SparcV9CodeEmitter.cpp --------------------------------------------===// // // 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. // //===----------------------------------------------------------------------===// // // SPARC-specific backend for emitting machine code to memory. // // This module also contains the code for lazily resolving the targets of call // instructions, including the callback used to redirect calls to functions for // which the code has not yet been generated into the JIT compiler. // // This file #includes SparcV9GenCodeEmitter.inc, which contains the code for // getBinaryCodeForInstr(), a method that converts a MachineInstr into the // corresponding binary machine code word. // //===----------------------------------------------------------------------===// #include "llvm/Constants.h" #include "llvm/Function.h" #include "llvm/GlobalVariable.h" #include "llvm/PassManager.h" #include "llvm/CodeGen/MachineCodeEmitter.h" #include "llvm/CodeGen/MachineConstantPool.h" #include "llvm/CodeGen/MachineFunctionPass.h" #include "llvm/CodeGen/MachineInstr.h" #include "llvm/Target/TargetMachine.h" #include "llvm/Target/TargetData.h" #include "llvm/Support/Debug.h" #include "SparcV9Internals.h" #include "SparcV9TargetMachine.h" #include "SparcV9RegInfo.h" #include "SparcV9CodeEmitter.h" #include "SparcV9Relocations.h" #include "MachineFunctionInfo.h" using namespace llvm; bool SparcV9TargetMachine::addPassesToEmitMachineCode(FunctionPassManager &PM, MachineCodeEmitter &MCE) { PM.add(new SparcV9CodeEmitter(*this, MCE)); PM.add(createSparcV9MachineCodeDestructionPass()); return false; } SparcV9CodeEmitter::SparcV9CodeEmitter(TargetMachine &tm, MachineCodeEmitter &M): TM(tm), MCE(M) {} void SparcV9CodeEmitter::emitWord(unsigned Val) { MCE.emitWord(Val); } unsigned SparcV9CodeEmitter::getRealRegNum(unsigned fakeReg, MachineInstr &MI) { const SparcV9RegInfo &RI = *TM.getRegInfo(); unsigned regClass = 0, regType = RI.getRegType(fakeReg); // At least map fakeReg into its class fakeReg = RI.getClassRegNum(fakeReg, regClass); switch (regClass) { case SparcV9RegInfo::IntRegClassID: { // SparcV9 manual, p31 static const unsigned IntRegMap[] = { // "o0", "o1", "o2", "o3", "o4", "o5", "o7", 8, 9, 10, 11, 12, 13, 15, // "l0", "l1", "l2", "l3", "l4", "l5", "l6", "l7", 16, 17, 18, 19, 20, 21, 22, 23, // "i0", "i1", "i2", "i3", "i4", "i5", "i6", "i7", 24, 25, 26, 27, 28, 29, 30, 31, // "g0", "g1", "g2", "g3", "g4", "g5", "g6", "g7", 0, 1, 2, 3, 4, 5, 6, 7, // "o6" 14 }; return IntRegMap[fakeReg]; break; } case SparcV9RegInfo::FloatRegClassID: { DEBUG(std::cerr << "FP reg: " << fakeReg << "\n"); if (regType == SparcV9RegInfo::FPSingleRegType) { // only numbered 0-31, hence can already fit into 5 bits (and 6) DEBUG(std::cerr << "FP single reg, returning: " << fakeReg << "\n"); } else if (regType == SparcV9RegInfo::FPDoubleRegType) { // FIXME: This assumes that we only have 5-bit register fields! // From SparcV9 Manual, page 40. // The bit layout becomes: b[4], b[3], b[2], b[1], b[5] fakeReg |= (fakeReg >> 5) & 1; fakeReg &= 0x1f; DEBUG(std::cerr << "FP double reg, returning: " << fakeReg << "\n"); } return fakeReg; } case SparcV9RegInfo::IntCCRegClassID: { /* xcc, icc, ccr */ static const unsigned IntCCReg[] = { 6, 4, 2 }; assert(fakeReg < sizeof(IntCCReg)/sizeof(IntCCReg[0]) && "CC register out of bounds for IntCCReg map"); DEBUG(std::cerr << "IntCC reg: " << IntCCReg[fakeReg] << "\n"); return IntCCReg[fakeReg]; } case SparcV9RegInfo::FloatCCRegClassID: { /* These are laid out %fcc0 - %fcc3 => 0 - 3, so are correct */ DEBUG(std::cerr << "FP CC reg: " << fakeReg << "\n"); return fakeReg; } case SparcV9RegInfo::SpecialRegClassID: { // Currently only "special" reg is %fsr, which is encoded as 1 in // instructions and 0 in SparcV9SpecialRegClass. static const unsigned SpecialReg[] = { 1 }; assert(fakeReg < sizeof(SpecialReg)/sizeof(SpecialReg[0]) && "Special register out of bounds for SpecialReg map"); DEBUG(std::cerr << "Special reg: " << SpecialReg[fakeReg] << "\n"); return SpecialReg[fakeReg]; } default: assert(0 && "Invalid unified register number in getRealRegNum"); return fakeReg; } } int64_t SparcV9CodeEmitter::getMachineOpValue(MachineInstr &MI, MachineOperand &MO) { int64_t rv = 0; // Return value; defaults to 0 for unhandled cases // or things that get fixed up later by the JIT. if (MO.isPCRelativeDisp() || MO.isGlobalAddress()) { DEBUG(std::cerr << "PCRelativeDisp: "); Value *V = MO.getVRegValue(); if (BasicBlock *BB = dyn_cast(V)) { DEBUG(std::cerr << "Saving reference to BB (VReg)\n"); unsigned* CurrPC = (unsigned*)(intptr_t)MCE.getCurrentPCValue(); BBRefs.push_back(std::make_pair(BB, std::make_pair(CurrPC, &MI))); } else if (const ConstantInt *CI = dyn_cast(V)) { // The real target of the branch is CI = PC + (rv * 4) // So undo that: give the instruction (CI - PC) / 4 rv = (CI->getRawValue() - MCE.getCurrentPCValue()) / 4; } else if (GlobalValue *GV = dyn_cast(V)) { unsigned Reloc = 0; if (MI.getOpcode() == V9::CALL) { Reloc = V9::reloc_pcrel_call; } else if (MI.getOpcode() == V9::SETHI) { if (MO.isHiBits64()) Reloc = V9::reloc_sethi_hh; else if (MO.isHiBits32()) Reloc = V9::reloc_sethi_lm; else assert(0 && "Unknown relocation!"); } else if (MI.getOpcode() == V9::ORi) { if (MO.isLoBits32()) Reloc = V9::reloc_or_lo; else if (MO.isLoBits64()) Reloc = V9::reloc_or_hm; else assert(0 && "Unknown relocation!"); } else { assert(0 && "Unknown relocation!"); } MCE.addRelocation(MachineRelocation(MCE.getCurrentPCOffset(), Reloc, GV)); rv = 0; } else { std::cerr << "ERROR: PC relative disp unhandled:" << MO << "\n"; abort(); } } else if (MO.isRegister() || MO.getType() == MachineOperand::MO_CCRegister) { // This is necessary because the SparcV9 backend 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 FP, SP, etc. unsigned fakeReg = MO.getReg(); unsigned realRegByClass = getRealRegNum(fakeReg, MI); DEBUG(std::cerr << MO << ": Reg[" << std::dec << fakeReg << "] => " << realRegByClass << " (LLC: " << TM.getRegInfo()->getUnifiedRegName(fakeReg) << ")\n"); rv = realRegByClass; } else if (MO.isImmediate()) { rv = MO.getImmedValue(); DEBUG(std::cerr << "immed: " << rv << "\n"); } else if (MO.isMachineBasicBlock()) { // Duplicate code of the above case for VirtualRegister, BasicBlock... // It should really hit this case, but SparcV9 backend uses VRegs instead DEBUG(std::cerr << "Saving reference to MBB\n"); const BasicBlock *BB = MO.getMachineBasicBlock()->getBasicBlock(); unsigned* CurrPC = (unsigned*)(intptr_t)MCE.getCurrentPCValue(); BBRefs.push_back(std::make_pair(BB, std::make_pair(CurrPC, &MI))); } else if (MO.isExternalSymbol()) { // SparcV9 backend doesn't generate this (yet...) std::cerr << "ERROR: External symbol unhandled: " << MO << "\n"; abort(); } else if (MO.isFrameIndex()) { // SparcV9 backend doesn't generate this (yet...) int FrameIndex = MO.getFrameIndex(); std::cerr << "ERROR: Frame index unhandled.\n"; abort(); } else if (MO.isConstantPoolIndex()) { unsigned Index = MO.getConstantPoolIndex(); rv = MCE.getConstantPoolEntryAddress(Index); } else { std::cerr << "ERROR: Unknown type of MachineOperand: " << MO << "\n"; abort(); } // Finally, deal with the various bitfield-extracting functions that // 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.isLoBits32()) { // %lo(val) == %lo() in SparcV9 ABI doc return rv & 0x03ff; } else if (MO.isHiBits32()) { // %lm(val) == %hi() in SparcV9 ABI doc return (rv >> 10) & 0x03fffff; } else if (MO.isLoBits64()) { // %hm(val) == %ulo() in SparcV9 ABI doc return (rv >> 32) & 0x03ff; } else if (MO.isHiBits64()) { // %hh(val) == %uhi() in SparcV9 ABI doc return rv >> 42; } else { // (unadorned) val return rv; } } unsigned SparcV9CodeEmitter::getValueBit(int64_t Val, unsigned bit) { Val >>= bit; return (Val & 1); } bool SparcV9CodeEmitter::runOnMachineFunction(MachineFunction &MF) { MCE.startFunction(MF); DEBUG(std::cerr << "Starting function " << MF.getFunction()->getName() << ", address: " << "0x" << std::hex << (long)MCE.getCurrentPCValue() << "\n"); MCE.emitConstantPool(MF.getConstantPool()); for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) emitBasicBlock(*I); MCE.finishFunction(MF); DEBUG(std::cerr << "Finishing fn " << MF.getFunction()->getName() << "\n"); // Resolve branches to BasicBlocks for the entire function for (unsigned i = 0, e = BBRefs.size(); i != e; ++i) { long Location = BBLocations[BBRefs[i].first]; unsigned *Ref = BBRefs[i].second.first; MachineInstr *MI = BBRefs[i].second.second; DEBUG(std::cerr << "Fixup @ " << std::hex << Ref << " to 0x" << Location << " in instr: " << std::dec << *MI); for (unsigned ii = 0, ee = MI->getNumOperands(); ii != ee; ++ii) { MachineOperand &op = MI->getOperand(ii); if (op.isPCRelativeDisp()) { // the instruction's branch target is made such that it branches to // PC + (branchTarget * 4), so undo that arithmetic here: // Location is the target of the branch // Ref is the location of the instruction, and hence the PC int64_t branchTarget = (Location - (long)Ref) >> 2; // Save the flags. bool loBits32=false, hiBits32=false, loBits64=false, hiBits64=false; if (op.isLoBits32()) { loBits32=true; } if (op.isHiBits32()) { hiBits32=true; } if (op.isLoBits64()) { loBits64=true; } if (op.isHiBits64()) { hiBits64=true; } MI->SetMachineOperandConst(ii, MachineOperand::MO_SignExtendedImmed, branchTarget); if (loBits32) { MI->getOperand(ii).markLo32(); } else if (hiBits32) { MI->getOperand(ii).markHi32(); } else if (loBits64) { MI->getOperand(ii).markLo64(); } else if (hiBits64) { MI->getOperand(ii).markHi64(); } DEBUG(std::cerr << "Rewrote BB ref: "); unsigned fixedInstr = SparcV9CodeEmitter::getBinaryCodeForInstr(*MI); MCE.emitWordAt (fixedInstr, Ref); break; } } } BBRefs.clear(); BBLocations.clear(); return false; } void SparcV9CodeEmitter::emitBasicBlock(MachineBasicBlock &MBB) { currBB = MBB.getBasicBlock(); BBLocations[currBB] = MCE.getCurrentPCValue(); for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); I != E; ++I) if (I->getOpcode() != V9::RDCCR) { emitWord(getBinaryCodeForInstr(*I)); } else { // FIXME: The tblgen produced code emitter cannot deal with the fact that // machine operand #0 of the RDCCR instruction should be ignored. This is // really a bug in the representation of the RDCCR instruction (which has // no need to explicitly represent the CCR dest), but we hack around it // here. unsigned RegNo = getMachineOpValue(*I, I->getOperand(1)); RegNo &= (1<<5)-1; emitWord((RegNo << 25) | 2168487936U); } } #include "SparcV9GenCodeEmitter.inc"