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Diffstat (limited to 'lib/Target/Alpha/AlphaCodeEmitter.cpp')
-rw-r--r-- | lib/Target/Alpha/AlphaCodeEmitter.cpp | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/lib/Target/Alpha/AlphaCodeEmitter.cpp b/lib/Target/Alpha/AlphaCodeEmitter.cpp new file mode 100644 index 0000000000..f198883fdf --- /dev/null +++ b/lib/Target/Alpha/AlphaCodeEmitter.cpp @@ -0,0 +1,231 @@ +//===-- Alpha/AlphaCodeEmitter.cpp - Convert Alpha code to machine code ---===// +// +// 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. +// +//===----------------------------------------------------------------------===// +// +// This file contains the pass that transforms the Alpha machine instructions +// into relocatable machine code. +// +//===----------------------------------------------------------------------===// + +#include "AlphaTargetMachine.h" +#include "AlphaRelocations.h" +#include "Alpha.h" +#include "llvm/PassManager.h" +#include "llvm/CodeGen/MachineCodeEmitter.h" +#include "llvm/CodeGen/MachineFunctionPass.h" +#include "llvm/CodeGen/MachineInstr.h" +#include "llvm/CodeGen/Passes.h" +#include "llvm/Function.h" +#include "llvm/Support/Debug.h" +#include "llvm/ADT/Statistic.h" +using namespace llvm; + +namespace { + Statistic<> + NumEmitted("alpha-emitter", "Number of machine instructions emitted"); +} + +namespace { + class AlphaCodeEmitter : public MachineFunctionPass { + const AlphaInstrInfo *II; + MachineCodeEmitter &MCE; + std::map<const MachineBasicBlock*, unsigned*> BasicBlockAddrs; + std::vector<std::pair<const MachineBasicBlock *, unsigned*> > BBRefs; + + /// getMachineOpValue - evaluates the MachineOperand of a given MachineInstr + /// + int getMachineOpValue(MachineInstr &MI, MachineOperand &MO); + + public: + explicit AlphaCodeEmitter(MachineCodeEmitter &mce) : II(0), MCE(mce) {} + AlphaCodeEmitter(MachineCodeEmitter &mce, const AlphaInstrInfo& ii) + : II(&ii), MCE(mce) {} + + bool runOnMachineFunction(MachineFunction &MF); + + virtual const char *getPassName() const { + return "Alpha Machine Code Emitter"; + } + + void emitInstruction(const MachineInstr &MI); + + /// emitWord - write a 32-bit word to memory at the current PC + /// + void emitWord(unsigned w) { MCE.emitWord(w); } + + /// getBinaryCodeForInstr - This function, generated by the + /// CodeEmitterGenerator using TableGen, produces the binary encoding for + /// machine instructions. + /// + unsigned getBinaryCodeForInstr(MachineInstr &MI); + + private: + void emitBasicBlock(MachineBasicBlock &MBB); + + }; +} + +/// createAlphaCodeEmitterPass - Return a pass that emits the collected Alpha code +/// to the specified MCE object. +FunctionPass *llvm::createAlphaCodeEmitterPass(MachineCodeEmitter &MCE) { + return new AlphaCodeEmitter(MCE); +} + +bool AlphaCodeEmitter::runOnMachineFunction(MachineFunction &MF) { + II = ((AlphaTargetMachine&)MF.getTarget()).getInstrInfo(); + + MCE.startFunction(MF); + MCE.emitConstantPool(MF.getConstantPool()); + for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) + emitBasicBlock(*I); + MCE.finishFunction(MF); + + // Resolve all forward branches now... + for (unsigned i = 0, e = BBRefs.size(); i != e; ++i) { + unsigned* Location = (unsigned*)BasicBlockAddrs[BBRefs[i].first]; + unsigned* Ref = (unsigned*)BBRefs[i].second; + intptr_t BranchTargetDisp = (((unsigned char*)Location - (unsigned char*)Ref) >> 2) - 1; + DEBUG(std::cerr << "Fixup @ " << (void*)Ref << " to " << (void*)Location + << " Disp " << BranchTargetDisp << " using " << (BranchTargetDisp & ((1 << 22)-1)) << "\n"); + *Ref |= (BranchTargetDisp & ((1 << 21)-1)); + } + BBRefs.clear(); + BasicBlockAddrs.clear(); + + return false; +} + +void AlphaCodeEmitter::emitBasicBlock(MachineBasicBlock &MBB) { + uint64_t Addr = MCE.getCurrentPCValue(); + BasicBlockAddrs[&MBB] = (unsigned*)Addr; + + for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); + I != E; ++I) { + MachineInstr &MI = *I; + unsigned Opcode = MI.getOpcode(); + switch(MI.getOpcode()) { + default: + emitWord(getBinaryCodeForInstr(*I)); + break; + case Alpha::ALTENT: + case Alpha::PCLABEL: + case Alpha::MEMLABEL: + break; //skip these + } + } +} + +static unsigned getAlphaRegNumber(unsigned Reg) { + switch (Reg) { + case Alpha::R0 : case Alpha::F0 : return 0; + case Alpha::R1 : case Alpha::F1 : return 1; + case Alpha::R2 : case Alpha::F2 : return 2; + case Alpha::R3 : case Alpha::F3 : return 3; + case Alpha::R4 : case Alpha::F4 : return 4; + case Alpha::R5 : case Alpha::F5 : return 5; + case Alpha::R6 : case Alpha::F6 : return 6; + case Alpha::R7 : case Alpha::F7 : return 7; + case Alpha::R8 : case Alpha::F8 : return 8; + case Alpha::R9 : case Alpha::F9 : return 9; + case Alpha::R10 : case Alpha::F10 : return 10; + case Alpha::R11 : case Alpha::F11 : return 11; + case Alpha::R12 : case Alpha::F12 : return 12; + case Alpha::R13 : case Alpha::F13 : return 13; + case Alpha::R14 : case Alpha::F14 : return 14; + case Alpha::R15 : case Alpha::F15 : return 15; + case Alpha::R16 : case Alpha::F16 : return 16; + case Alpha::R17 : case Alpha::F17 : return 17; + case Alpha::R18 : case Alpha::F18 : return 18; + case Alpha::R19 : case Alpha::F19 : return 19; + case Alpha::R20 : case Alpha::F20 : return 20; + case Alpha::R21 : case Alpha::F21 : return 21; + case Alpha::R22 : case Alpha::F22 : return 22; + case Alpha::R23 : case Alpha::F23 : return 23; + case Alpha::R24 : case Alpha::F24 : return 24; + case Alpha::R25 : case Alpha::F25 : return 25; + case Alpha::R26 : case Alpha::F26 : return 26; + case Alpha::R27 : case Alpha::F27 : return 27; + case Alpha::R28 : case Alpha::F28 : return 28; + case Alpha::R29 : case Alpha::F29 : return 29; + case Alpha::R30 : case Alpha::F30 : return 30; + case Alpha::R31 : case Alpha::F31 : return 31; + default: + assert(0 && "Unhandled reg"); + abort(); + } +} + +int AlphaCodeEmitter::getMachineOpValue(MachineInstr &MI, MachineOperand &MO) { + + int rv = 0; // Return value; defaults to 0 for unhandled cases + // or things that get fixed up later by the JIT. + + if (MO.isRegister()) { + rv = getAlphaRegNumber(MO.getReg()); + } else if (MO.isImmediate()) { + rv = MO.getImmedValue(); + } else if (MO.isGlobalAddress() || MO.isExternalSymbol() + || MO.isConstantPoolIndex()) { + DEBUG(std::cerr << MO << " is a relocated op for " << MI << "\n";); + bool isExternal = MO.isExternalSymbol() || + (MO.isGlobalAddress() && + ( MO.getGlobal()->hasWeakLinkage() || + MO.getGlobal()->isExternal()) ); + unsigned Reloc = 0; + int Offset = 0; + switch (MI.getOpcode()) { + case Alpha::LDLr: + case Alpha::LDQr: + case Alpha::LDBUr: + case Alpha::LDWUr: + case Alpha::LDSr: + case Alpha::LDTr: + case Alpha::LDAr: + Reloc = Alpha::reloc_gprellow; + break; + case Alpha::LDAHr: + Reloc = Alpha::reloc_gprelhigh; + break; + case Alpha::LDQl: + Reloc = Alpha::reloc_literal; + break; + case Alpha::LDAg: + case Alpha::LDAHg: + Reloc = Alpha::reloc_gpdist; + Offset = MI.getOperand(3).getImmedValue(); + break; + default: + assert(0 && "unknown relocatable instruction"); + abort(); + } + if (MO.isGlobalAddress()) + MCE.addRelocation(MachineRelocation((unsigned)MCE.getCurrentPCOffset(), + Reloc, MO.getGlobal(), Offset, + true, true)); + else if (MO.isExternalSymbol()) + MCE.addRelocation(MachineRelocation((unsigned)MCE.getCurrentPCOffset(), + Reloc, MO.getSymbolName(), Offset, + true)); + else + MCE.addRelocation(MachineRelocation((unsigned)MCE.getCurrentPCOffset(), + Reloc, MO.getConstantPoolIndex(), + Offset)); + } else if (MO.isMachineBasicBlock()) { + unsigned* CurrPC = (unsigned*)MCE.getCurrentPCValue(); + BBRefs.push_back(std::make_pair(MO.getMachineBasicBlock(), CurrPC)); + }else { + std::cerr << "ERROR: Unknown type of MachineOperand: " << MO << "\n"; + abort(); + } + + return rv; +} + + +#include "AlphaGenCodeEmitter.inc" + |