diff options
Diffstat (limited to 'contrib/llvm/lib/Target/ARM/ARMMCInstLower.cpp')
-rw-r--r-- | contrib/llvm/lib/Target/ARM/ARMMCInstLower.cpp | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/ARM/ARMMCInstLower.cpp b/contrib/llvm/lib/Target/ARM/ARMMCInstLower.cpp new file mode 100644 index 0000000..a2aca2d --- /dev/null +++ b/contrib/llvm/lib/Target/ARM/ARMMCInstLower.cpp @@ -0,0 +1,163 @@ +//===-- ARMMCInstLower.cpp - Convert ARM MachineInstr to an MCInst --------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file contains code to lower ARM MachineInstrs to their corresponding +// MCInst records. +// +//===----------------------------------------------------------------------===// + +#include "ARM.h" +#include "ARMAsmPrinter.h" +#include "MCTargetDesc/ARMBaseInfo.h" +#include "MCTargetDesc/ARMMCExpr.h" +#include "llvm/CodeGen/MachineBasicBlock.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/Mangler.h" +#include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCInst.h" +using namespace llvm; + + +MCOperand ARMAsmPrinter::GetSymbolRef(const MachineOperand &MO, + const MCSymbol *Symbol) { + const MCExpr *Expr; + unsigned Option = MO.getTargetFlags() & ARMII::MO_OPTION_MASK; + switch (Option) { + default: { + Expr = MCSymbolRefExpr::create(Symbol, MCSymbolRefExpr::VK_None, + OutContext); + switch (Option) { + default: llvm_unreachable("Unknown target flag on symbol operand"); + case ARMII::MO_NO_FLAG: + break; + case ARMII::MO_LO16: + Expr = MCSymbolRefExpr::create(Symbol, MCSymbolRefExpr::VK_None, + OutContext); + Expr = ARMMCExpr::createLower16(Expr, OutContext); + break; + case ARMII::MO_HI16: + Expr = MCSymbolRefExpr::create(Symbol, MCSymbolRefExpr::VK_None, + OutContext); + Expr = ARMMCExpr::createUpper16(Expr, OutContext); + break; + } + break; + } + + case ARMII::MO_PLT: + Expr = MCSymbolRefExpr::create(Symbol, MCSymbolRefExpr::VK_PLT, + OutContext); + break; + } + + if (!MO.isJTI() && MO.getOffset()) + Expr = MCBinaryExpr::createAdd(Expr, + MCConstantExpr::create(MO.getOffset(), + OutContext), + OutContext); + return MCOperand::createExpr(Expr); + +} + +bool ARMAsmPrinter::lowerOperand(const MachineOperand &MO, + MCOperand &MCOp) { + switch (MO.getType()) { + default: llvm_unreachable("unknown operand type"); + case MachineOperand::MO_Register: + // Ignore all non-CPSR implicit register operands. + if (MO.isImplicit() && MO.getReg() != ARM::CPSR) + return false; + assert(!MO.getSubReg() && "Subregs should be eliminated!"); + MCOp = MCOperand::createReg(MO.getReg()); + break; + case MachineOperand::MO_Immediate: + MCOp = MCOperand::createImm(MO.getImm()); + break; + case MachineOperand::MO_MachineBasicBlock: + MCOp = MCOperand::createExpr(MCSymbolRefExpr::create( + MO.getMBB()->getSymbol(), OutContext)); + break; + case MachineOperand::MO_GlobalAddress: { + MCOp = GetSymbolRef(MO, + GetARMGVSymbol(MO.getGlobal(), MO.getTargetFlags())); + break; + } + case MachineOperand::MO_ExternalSymbol: + MCOp = GetSymbolRef(MO, + GetExternalSymbolSymbol(MO.getSymbolName())); + break; + case MachineOperand::MO_JumpTableIndex: + MCOp = GetSymbolRef(MO, GetJTISymbol(MO.getIndex())); + break; + case MachineOperand::MO_ConstantPoolIndex: + MCOp = GetSymbolRef(MO, GetCPISymbol(MO.getIndex())); + break; + case MachineOperand::MO_BlockAddress: + MCOp = GetSymbolRef(MO, GetBlockAddressSymbol(MO.getBlockAddress())); + break; + case MachineOperand::MO_FPImmediate: { + APFloat Val = MO.getFPImm()->getValueAPF(); + bool ignored; + Val.convert(APFloat::IEEEdouble, APFloat::rmTowardZero, &ignored); + MCOp = MCOperand::createFPImm(Val.convertToDouble()); + break; + } + case MachineOperand::MO_RegisterMask: + // Ignore call clobbers. + return false; + } + return true; +} + +void llvm::LowerARMMachineInstrToMCInst(const MachineInstr *MI, MCInst &OutMI, + ARMAsmPrinter &AP) { + OutMI.setOpcode(MI->getOpcode()); + + // In the MC layer, we keep modified immediates in their encoded form + bool EncodeImms = false; + switch (MI->getOpcode()) { + default: break; + case ARM::MOVi: + case ARM::MVNi: + case ARM::CMPri: + case ARM::CMNri: + case ARM::TSTri: + case ARM::TEQri: + case ARM::MSRi: + case ARM::ADCri: + case ARM::ADDri: + case ARM::ADDSri: + case ARM::SBCri: + case ARM::SUBri: + case ARM::SUBSri: + case ARM::ANDri: + case ARM::ORRri: + case ARM::EORri: + case ARM::BICri: + case ARM::RSBri: + case ARM::RSBSri: + case ARM::RSCri: + EncodeImms = true; + break; + } + + for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { + const MachineOperand &MO = MI->getOperand(i); + + MCOperand MCOp; + if (AP.lowerOperand(MO, MCOp)) { + if (MCOp.isImm() && EncodeImms) { + int32_t Enc = ARM_AM::getSOImmVal(MCOp.getImm()); + if (Enc != -1) + MCOp.setImm(Enc); + } + OutMI.addOperand(MCOp); + } + } +} |