1 //=-- BPFMCInstLower.cpp - Convert BPF MachineInstr to an MCInst ------------=//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains code to lower BPF MachineInstrs to their corresponding
13 //===----------------------------------------------------------------------===//
15 #include "BPFMCInstLower.h"
16 #include "llvm/CodeGen/AsmPrinter.h"
17 #include "llvm/CodeGen/MachineBasicBlock.h"
18 #include "llvm/CodeGen/MachineInstr.h"
19 #include "llvm/MC/MCAsmInfo.h"
20 #include "llvm/MC/MCContext.h"
21 #include "llvm/MC/MCExpr.h"
22 #include "llvm/MC/MCInst.h"
23 #include "llvm/Support/ErrorHandling.h"
24 #include "llvm/Support/raw_ostream.h"
28 BPFMCInstLower::GetGlobalAddressSymbol(const MachineOperand &MO) const {
29 return Printer.getSymbol(MO.getGlobal());
33 BPFMCInstLower::GetExternalSymbolSymbol(const MachineOperand &MO) const {
34 return Printer.GetExternalSymbolSymbol(MO.getSymbolName());
37 MCOperand BPFMCInstLower::LowerSymbolOperand(const MachineOperand &MO,
38 MCSymbol *Sym) const {
40 const MCExpr *Expr = MCSymbolRefExpr::create(Sym, Ctx);
42 if (!MO.isJTI() && MO.getOffset())
43 llvm_unreachable("unknown symbol op");
45 return MCOperand::createExpr(Expr);
48 void BPFMCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
49 OutMI.setOpcode(MI->getOpcode());
51 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
52 const MachineOperand &MO = MI->getOperand(i);
55 switch (MO.getType()) {
58 llvm_unreachable("unknown operand type");
59 case MachineOperand::MO_Register:
60 // Ignore all implicit register operands.
63 MCOp = MCOperand::createReg(MO.getReg());
65 case MachineOperand::MO_Immediate:
66 MCOp = MCOperand::createImm(MO.getImm());
68 case MachineOperand::MO_MachineBasicBlock:
69 MCOp = MCOperand::createExpr(
70 MCSymbolRefExpr::create(MO.getMBB()->getSymbol(), Ctx));
72 case MachineOperand::MO_RegisterMask:
74 case MachineOperand::MO_ExternalSymbol:
75 MCOp = LowerSymbolOperand(MO, GetExternalSymbolSymbol(MO));
77 case MachineOperand::MO_GlobalAddress:
78 MCOp = LowerSymbolOperand(MO, GetGlobalAddressSymbol(MO));
82 OutMI.addOperand(MCOp);