| // WebAssemblyMCInstLower.cpp - Convert WebAssembly 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. |
| // |
| //===----------------------------------------------------------------------===// |
| /// |
| /// \file |
| /// \brief This file contains code to lower WebAssembly MachineInstrs to their |
| /// corresponding MCInst records. |
| /// |
| //===----------------------------------------------------------------------===// |
| |
| #include "WebAssemblyMCInstLower.h" |
| #include "WebAssemblyMachineFunctionInfo.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/CodeGen/AsmPrinter.h" |
| #include "llvm/CodeGen/MachineFunction.h" |
| #include "llvm/IR/Constants.h" |
| #include "llvm/MC/MCAsmInfo.h" |
| #include "llvm/MC/MCContext.h" |
| #include "llvm/MC/MCExpr.h" |
| #include "llvm/MC/MCInst.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/raw_ostream.h" |
| using namespace llvm; |
| |
| MCSymbol * |
| WebAssemblyMCInstLower::GetGlobalAddressSymbol(const MachineOperand &MO) const { |
| return Printer.getSymbol(MO.getGlobal()); |
| } |
| |
| MCSymbol *WebAssemblyMCInstLower::GetExternalSymbolSymbol( |
| const MachineOperand &MO) const { |
| return Printer.GetExternalSymbolSymbol(MO.getSymbolName()); |
| } |
| |
| MCOperand WebAssemblyMCInstLower::LowerSymbolOperand(const MachineOperand &MO, |
| MCSymbol *Sym) const { |
| assert(MO.getTargetFlags() == 0 && "WebAssembly does not use target flags"); |
| |
| const MCExpr *Expr = MCSymbolRefExpr::create(Sym, Ctx); |
| |
| int64_t Offset = MO.getOffset(); |
| if (Offset != 0) { |
| assert(!MO.isJTI() && "Unexpected offset with jump table index"); |
| Expr = |
| MCBinaryExpr::createAdd(Expr, MCConstantExpr::create(Offset, Ctx), Ctx); |
| } |
| |
| return MCOperand::createExpr(Expr); |
| } |
| |
| void WebAssemblyMCInstLower::Lower(const MachineInstr *MI, |
| MCInst &OutMI) const { |
| OutMI.setOpcode(MI->getOpcode()); |
| |
| for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { |
| const MachineOperand &MO = MI->getOperand(i); |
| |
| MCOperand MCOp; |
| switch (MO.getType()) { |
| default: |
| MI->dump(); |
| llvm_unreachable("unknown operand type"); |
| case MachineOperand::MO_Register: { |
| // Ignore all implicit register operands. |
| if (MO.isImplicit()) |
| continue; |
| const WebAssemblyFunctionInfo &MFI = |
| *MI->getParent()->getParent()->getInfo<WebAssemblyFunctionInfo>(); |
| unsigned WAReg = MFI.getWAReg(MO.getReg()); |
| MCOp = MCOperand::createReg(WAReg); |
| break; |
| } |
| case MachineOperand::MO_Immediate: |
| MCOp = MCOperand::createImm(MO.getImm()); |
| break; |
| case MachineOperand::MO_FPImmediate: { |
| // TODO: MC converts all floating point immediate operands to double. |
| // This is fine for numeric values, but may cause NaNs to change bits. |
| const ConstantFP *Imm = MO.getFPImm(); |
| if (Imm->getType()->isFloatTy()) |
| MCOp = MCOperand::createFPImm(Imm->getValueAPF().convertToFloat()); |
| else if (Imm->getType()->isDoubleTy()) |
| MCOp = MCOperand::createFPImm(Imm->getValueAPF().convertToDouble()); |
| else |
| llvm_unreachable("unknown floating point immediate type"); |
| break; |
| } |
| case MachineOperand::MO_MachineBasicBlock: |
| MCOp = MCOperand::createExpr( |
| MCSymbolRefExpr::create(MO.getMBB()->getSymbol(), Ctx)); |
| break; |
| case MachineOperand::MO_GlobalAddress: |
| MCOp = LowerSymbolOperand(MO, GetGlobalAddressSymbol(MO)); |
| break; |
| case MachineOperand::MO_ExternalSymbol: |
| MCOp = LowerSymbolOperand(MO, GetExternalSymbolSymbol(MO)); |
| break; |
| } |
| |
| OutMI.addOperand(MCOp); |
| } |
| } |