| //===-- PPCCodeEmitter.cpp - JIT Code Emitter for PowerPC32 -------*- C++ -*-=// | 
 | // | 
 | //                     The LLVM Compiler Infrastructure | 
 | // | 
 | // This file is distributed under the University of Illinois Open Source | 
 | // License. See LICENSE.TXT for details. | 
 | // | 
 | //===----------------------------------------------------------------------===// | 
 | // | 
 | // This file defines the PowerPC 32-bit CodeEmitter and associated machinery to | 
 | // JIT-compile bitcode to native PowerPC. | 
 | // | 
 | //===----------------------------------------------------------------------===// | 
 |  | 
 | #include "PPCTargetMachine.h" | 
 | #include "PPCRelocations.h" | 
 | #include "PPC.h" | 
 | #include "llvm/Module.h" | 
 | #include "llvm/PassManager.h" | 
 | #include "llvm/CodeGen/JITCodeEmitter.h" | 
 | #include "llvm/CodeGen/MachineFunctionPass.h" | 
 | #include "llvm/CodeGen/MachineInstrBuilder.h" | 
 | #include "llvm/CodeGen/MachineModuleInfo.h" | 
 | #include "llvm/Support/ErrorHandling.h" | 
 | #include "llvm/Support/raw_ostream.h" | 
 | #include "llvm/Target/TargetOptions.h" | 
 | using namespace llvm; | 
 |  | 
 | namespace { | 
 |   class PPCCodeEmitter : public MachineFunctionPass { | 
 |     TargetMachine &TM; | 
 |     JITCodeEmitter &MCE; | 
 |     MachineModuleInfo *MMI; | 
 |      | 
 |     void getAnalysisUsage(AnalysisUsage &AU) const { | 
 |       AU.addRequired<MachineModuleInfo>(); | 
 |       MachineFunctionPass::getAnalysisUsage(AU); | 
 |     } | 
 |      | 
 |     static char ID; | 
 |      | 
 |     /// MovePCtoLROffset - When/if we see a MovePCtoLR instruction, we record | 
 |     /// its address in the function into this pointer. | 
 |     void *MovePCtoLROffset; | 
 |   public: | 
 |      | 
 |     PPCCodeEmitter(TargetMachine &tm, JITCodeEmitter &mce) | 
 |       : MachineFunctionPass(ID), TM(tm), MCE(mce) {} | 
 |  | 
 |     /// getBinaryCodeForInstr - This function, generated by the | 
 |     /// CodeEmitterGenerator using TableGen, produces the binary encoding for | 
 |     /// machine instructions. | 
 |  | 
 |     unsigned getBinaryCodeForInstr(const MachineInstr &MI); | 
 |  | 
 |     /// getMachineOpValue - evaluates the MachineOperand of a given MachineInstr | 
 |  | 
 |     unsigned getMachineOpValue(const MachineInstr &MI, | 
 |                                const MachineOperand &MO); | 
 |  | 
 |     const char *getPassName() const { return "PowerPC Machine Code Emitter"; } | 
 |  | 
 |     /// runOnMachineFunction - emits the given MachineFunction to memory | 
 |     /// | 
 |     bool runOnMachineFunction(MachineFunction &MF); | 
 |  | 
 |     /// emitBasicBlock - emits the given MachineBasicBlock to memory | 
 |     /// | 
 |     void emitBasicBlock(MachineBasicBlock &MBB); | 
 |   }; | 
 | } | 
 |  | 
 | char PPCCodeEmitter::ID = 0; | 
 |  | 
 | /// createPPCCodeEmitterPass - Return a pass that emits the collected PPC code | 
 | /// to the specified MCE object. | 
 | FunctionPass *llvm::createPPCJITCodeEmitterPass(PPCTargetMachine &TM, | 
 |                                                 JITCodeEmitter &JCE) { | 
 |   return new PPCCodeEmitter(TM, JCE); | 
 | } | 
 |  | 
 | bool PPCCodeEmitter::runOnMachineFunction(MachineFunction &MF) { | 
 |   assert((MF.getTarget().getRelocationModel() != Reloc::Default || | 
 |           MF.getTarget().getRelocationModel() != Reloc::Static) && | 
 |          "JIT relocation model must be set to static or default!"); | 
 |  | 
 |   MMI = &getAnalysis<MachineModuleInfo>(); | 
 |   MCE.setModuleInfo(MMI); | 
 |   do { | 
 |     MovePCtoLROffset = 0; | 
 |     MCE.startFunction(MF); | 
 |     for (MachineFunction::iterator BB = MF.begin(), E = MF.end(); BB != E; ++BB) | 
 |       emitBasicBlock(*BB); | 
 |   } while (MCE.finishFunction(MF)); | 
 |  | 
 |   return false; | 
 | } | 
 |  | 
 | void PPCCodeEmitter::emitBasicBlock(MachineBasicBlock &MBB) { | 
 |   MCE.StartMachineBasicBlock(&MBB); | 
 |  | 
 |   for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); I != E; ++I){ | 
 |     const MachineInstr &MI = *I; | 
 |     MCE.processDebugLoc(MI.getDebugLoc(), true); | 
 |     switch (MI.getOpcode()) { | 
 |     default: | 
 |       MCE.emitWordBE(getBinaryCodeForInstr(MI)); | 
 |       break; | 
 |     case TargetOpcode::PROLOG_LABEL: | 
 |     case TargetOpcode::EH_LABEL: | 
 |       MCE.emitLabel(MI.getOperand(0).getMCSymbol()); | 
 |       break; | 
 |     case TargetOpcode::IMPLICIT_DEF: | 
 |     case TargetOpcode::KILL: | 
 |       break; // pseudo opcode, no side effects | 
 |     case PPC::MovePCtoLR: | 
 |     case PPC::MovePCtoLR8: | 
 |       assert(TM.getRelocationModel() == Reloc::PIC_); | 
 |       MovePCtoLROffset = (void*)MCE.getCurrentPCValue(); | 
 |       MCE.emitWordBE(0x48000005);   // bl 1 | 
 |       break; | 
 |     } | 
 |     MCE.processDebugLoc(MI.getDebugLoc(), false); | 
 |   } | 
 | } | 
 |  | 
 | unsigned PPCCodeEmitter::getMachineOpValue(const MachineInstr &MI, | 
 |                                            const MachineOperand &MO) { | 
 |  | 
 |   unsigned rv = 0; // Return value; defaults to 0 for unhandled cases | 
 |                    // or things that get fixed up later by the JIT. | 
 |   if (MO.isReg()) { | 
 |     rv = PPCRegisterInfo::getRegisterNumbering(MO.getReg()); | 
 |  | 
 |     // Special encoding for MTCRF and MFOCRF, which uses a bit mask for the | 
 |     // register, not the register number directly. | 
 |     if ((MI.getOpcode() == PPC::MTCRF || MI.getOpcode() == PPC::MFOCRF) && | 
 |         (MO.getReg() >= PPC::CR0 && MO.getReg() <= PPC::CR7)) { | 
 |       rv = 0x80 >> rv; | 
 |     } | 
 |   } else if (MO.isImm()) { | 
 |     rv = MO.getImm(); | 
 |   } else if (MO.isGlobal() || MO.isSymbol() || | 
 |              MO.isCPI() || MO.isJTI()) { | 
 |     unsigned Reloc = 0; | 
 |     if (MI.getOpcode() == PPC::BL_Darwin || MI.getOpcode() == PPC::BL8_Darwin || | 
 |         MI.getOpcode() == PPC::BL_SVR4 || MI.getOpcode() == PPC::BL8_ELF || | 
 |         MI.getOpcode() == PPC::TAILB || MI.getOpcode() == PPC::TAILB8) | 
 |       Reloc = PPC::reloc_pcrel_bx; | 
 |     else { | 
 |       if (TM.getRelocationModel() == Reloc::PIC_) { | 
 |         assert(MovePCtoLROffset && "MovePCtoLR not seen yet?"); | 
 |       } | 
 |       switch (MI.getOpcode()) { | 
 |       default: MI.dump(); llvm_unreachable("Unknown instruction for relocation!"); | 
 |       case PPC::LIS: | 
 |       case PPC::LIS8: | 
 |       case PPC::ADDIS: | 
 |       case PPC::ADDIS8: | 
 |         Reloc = PPC::reloc_absolute_high;       // Pointer to symbol | 
 |         break; | 
 |       case PPC::LI: | 
 |       case PPC::LI8: | 
 |       case PPC::LA: | 
 |       // Loads. | 
 |       case PPC::LBZ: | 
 |       case PPC::LBZ8: | 
 |       case PPC::LHA: | 
 |       case PPC::LHA8: | 
 |       case PPC::LHZ: | 
 |       case PPC::LHZ8: | 
 |       case PPC::LWZ: | 
 |       case PPC::LWZ8: | 
 |       case PPC::LFS: | 
 |       case PPC::LFD: | 
 |  | 
 |       // Stores. | 
 |       case PPC::STB: | 
 |       case PPC::STB8: | 
 |       case PPC::STH: | 
 |       case PPC::STH8: | 
 |       case PPC::STW: | 
 |       case PPC::STW8: | 
 |       case PPC::STFS: | 
 |       case PPC::STFD: | 
 |         Reloc = PPC::reloc_absolute_low; | 
 |         break; | 
 |  | 
 |       case PPC::LWA: | 
 |       case PPC::LD: | 
 |       case PPC::STD: | 
 |       case PPC::STD_32: | 
 |         Reloc = PPC::reloc_absolute_low_ix; | 
 |         break; | 
 |       } | 
 |     } | 
 |  | 
 |     MachineRelocation R; | 
 |     if (MO.isGlobal()) { | 
 |       R = MachineRelocation::getGV(MCE.getCurrentPCOffset(), Reloc, | 
 |                                    const_cast<GlobalValue *>(MO.getGlobal()), 0, | 
 |                                    isa<Function>(MO.getGlobal())); | 
 |     } else if (MO.isSymbol()) { | 
 |       R = MachineRelocation::getExtSym(MCE.getCurrentPCOffset(), | 
 |                                        Reloc, MO.getSymbolName(), 0); | 
 |     } else if (MO.isCPI()) { | 
 |       R = MachineRelocation::getConstPool(MCE.getCurrentPCOffset(), | 
 |                                           Reloc, MO.getIndex(), 0); | 
 |     } else { | 
 |       assert(MO.isJTI()); | 
 |       R = MachineRelocation::getJumpTable(MCE.getCurrentPCOffset(), | 
 |                                           Reloc, MO.getIndex(), 0); | 
 |     } | 
 |  | 
 |     // If in PIC mode, we need to encode the negated address of the | 
 |     // 'movepctolr' into the unrelocated field.  After relocation, we'll have | 
 |     // &gv-&movepctolr-4 in the imm field.  Once &movepctolr is added to the imm | 
 |     // field, we get &gv.  This doesn't happen for branch relocations, which are | 
 |     // always implicitly pc relative. | 
 |     if (TM.getRelocationModel() == Reloc::PIC_ && Reloc != PPC::reloc_pcrel_bx){ | 
 |       assert(MovePCtoLROffset && "MovePCtoLR not seen yet?"); | 
 |       R.setConstantVal(-(intptr_t)MovePCtoLROffset - 4); | 
 |     } | 
 |     MCE.addRelocation(R); | 
 |  | 
 |   } else if (MO.isMBB()) { | 
 |     unsigned Reloc = 0; | 
 |     unsigned Opcode = MI.getOpcode(); | 
 |     if (Opcode == PPC::B || Opcode == PPC::BL_Darwin || | 
 |         Opcode == PPC::BLA_Darwin|| Opcode == PPC::BL_SVR4 || | 
 |         Opcode == PPC::BLA_SVR4) | 
 |       Reloc = PPC::reloc_pcrel_bx; | 
 |     else // BCC instruction | 
 |       Reloc = PPC::reloc_pcrel_bcx; | 
 |  | 
 |     MCE.addRelocation(MachineRelocation::getBB(MCE.getCurrentPCOffset(), | 
 |                                                Reloc, MO.getMBB())); | 
 |   } else { | 
 | #ifndef NDEBUG | 
 |     errs() << "ERROR: Unknown type of MachineOperand: " << MO << "\n"; | 
 | #endif | 
 |     llvm_unreachable(0); | 
 |   } | 
 |  | 
 |   return rv; | 
 | } | 
 |  | 
 | #include "PPCGenCodeEmitter.inc" |