xref: /freebsd-src/contrib/llvm-project/llvm/lib/Target/BPF/BPFMCInstLower.cpp (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
10b57cec5SDimitry Andric //=-- BPFMCInstLower.cpp - Convert BPF MachineInstr to an MCInst ------------=//
20b57cec5SDimitry Andric //
30b57cec5SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
40b57cec5SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
50b57cec5SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
60b57cec5SDimitry Andric //
70b57cec5SDimitry Andric //===----------------------------------------------------------------------===//
80b57cec5SDimitry Andric //
90b57cec5SDimitry Andric // This file contains code to lower BPF MachineInstrs to their corresponding
100b57cec5SDimitry Andric // MCInst records.
110b57cec5SDimitry Andric //
120b57cec5SDimitry Andric //===----------------------------------------------------------------------===//
130b57cec5SDimitry Andric 
140b57cec5SDimitry Andric #include "BPFMCInstLower.h"
150b57cec5SDimitry Andric #include "llvm/CodeGen/AsmPrinter.h"
160b57cec5SDimitry Andric #include "llvm/CodeGen/MachineBasicBlock.h"
170b57cec5SDimitry Andric #include "llvm/CodeGen/MachineInstr.h"
180b57cec5SDimitry Andric #include "llvm/MC/MCAsmInfo.h"
190b57cec5SDimitry Andric #include "llvm/MC/MCContext.h"
200b57cec5SDimitry Andric #include "llvm/MC/MCExpr.h"
210b57cec5SDimitry Andric #include "llvm/MC/MCInst.h"
220b57cec5SDimitry Andric #include "llvm/Support/ErrorHandling.h"
230b57cec5SDimitry Andric #include "llvm/Support/raw_ostream.h"
240b57cec5SDimitry Andric using namespace llvm;
250b57cec5SDimitry Andric 
260b57cec5SDimitry Andric MCSymbol *
270b57cec5SDimitry Andric BPFMCInstLower::GetGlobalAddressSymbol(const MachineOperand &MO) const {
280b57cec5SDimitry Andric   return Printer.getSymbol(MO.getGlobal());
290b57cec5SDimitry Andric }
300b57cec5SDimitry Andric 
310b57cec5SDimitry Andric MCSymbol *
320b57cec5SDimitry Andric BPFMCInstLower::GetExternalSymbolSymbol(const MachineOperand &MO) const {
330b57cec5SDimitry Andric   return Printer.GetExternalSymbolSymbol(MO.getSymbolName());
340b57cec5SDimitry Andric }
350b57cec5SDimitry Andric 
360b57cec5SDimitry Andric MCOperand BPFMCInstLower::LowerSymbolOperand(const MachineOperand &MO,
370b57cec5SDimitry Andric                                              MCSymbol *Sym) const {
380b57cec5SDimitry Andric 
390b57cec5SDimitry Andric   const MCExpr *Expr = MCSymbolRefExpr::create(Sym, Ctx);
400b57cec5SDimitry Andric 
410b57cec5SDimitry Andric   if (!MO.isJTI() && MO.getOffset())
420b57cec5SDimitry Andric     llvm_unreachable("unknown symbol op");
430b57cec5SDimitry Andric 
440b57cec5SDimitry Andric   return MCOperand::createExpr(Expr);
450b57cec5SDimitry Andric }
460b57cec5SDimitry Andric 
470b57cec5SDimitry Andric void BPFMCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
480b57cec5SDimitry Andric   OutMI.setOpcode(MI->getOpcode());
490b57cec5SDimitry Andric 
504824e7fdSDimitry Andric   for (const MachineOperand &MO : MI->operands()) {
510b57cec5SDimitry Andric     MCOperand MCOp;
520b57cec5SDimitry Andric     switch (MO.getType()) {
530b57cec5SDimitry Andric     default:
540b57cec5SDimitry Andric       MI->print(errs());
550b57cec5SDimitry Andric       llvm_unreachable("unknown operand type");
560b57cec5SDimitry Andric     case MachineOperand::MO_Register:
570b57cec5SDimitry Andric       // Ignore all implicit register operands.
580b57cec5SDimitry Andric       if (MO.isImplicit())
590b57cec5SDimitry Andric         continue;
600b57cec5SDimitry Andric       MCOp = MCOperand::createReg(MO.getReg());
610b57cec5SDimitry Andric       break;
620b57cec5SDimitry Andric     case MachineOperand::MO_Immediate:
630b57cec5SDimitry Andric       MCOp = MCOperand::createImm(MO.getImm());
640b57cec5SDimitry Andric       break;
650b57cec5SDimitry Andric     case MachineOperand::MO_MachineBasicBlock:
660b57cec5SDimitry Andric       MCOp = MCOperand::createExpr(
670b57cec5SDimitry Andric           MCSymbolRefExpr::create(MO.getMBB()->getSymbol(), Ctx));
680b57cec5SDimitry Andric       break;
690b57cec5SDimitry Andric     case MachineOperand::MO_RegisterMask:
700b57cec5SDimitry Andric       continue;
710b57cec5SDimitry Andric     case MachineOperand::MO_ExternalSymbol:
720b57cec5SDimitry Andric       MCOp = LowerSymbolOperand(MO, GetExternalSymbolSymbol(MO));
730b57cec5SDimitry Andric       break;
740b57cec5SDimitry Andric     case MachineOperand::MO_GlobalAddress:
750b57cec5SDimitry Andric       MCOp = LowerSymbolOperand(MO, GetGlobalAddressSymbol(MO));
760b57cec5SDimitry Andric       break;
77*0fca6ea1SDimitry Andric     case MachineOperand::MO_ConstantPoolIndex:
78*0fca6ea1SDimitry Andric       MCOp = LowerSymbolOperand(MO, Printer.GetCPISymbol(MO.getIndex()));
79*0fca6ea1SDimitry Andric       break;
800b57cec5SDimitry Andric     }
810b57cec5SDimitry Andric 
820b57cec5SDimitry Andric     OutMI.addOperand(MCOp);
830b57cec5SDimitry Andric   }
840b57cec5SDimitry Andric }
85