llvm/lib/Target/SPIRV/SPIRVMCInstLower.cpp

   1 //=- SPIRVMCInstLower.cpp - Convert SPIR-V MachineInstr to MCInst -*- C++ -*-=//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file contains code to lower SPIR-V MachineInstrs to their corresponding
  10 // MCInst records.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "SPIRVMCInstLower.h"
  15 #include "SPIRV.h"
  16 #include "SPIRVModuleAnalysis.h"
  17 #include "SPIRVUtils.h"
  18 #include "llvm/CodeGen/MachineInstr.h"
  19 #include "llvm/IR/Constants.h"
  20
  21 using namespace llvm;
  22
  23 void SPIRVMCInstLower::lower(const MachineInstr *MI, MCInst &OutMI,
  24                              SPIRV::ModuleAnalysisInfo *MAI) const {
  25   OutMI.setOpcode(MI->getOpcode());
  26   // Propagate previously set flags
  27   OutMI.setFlags(MI->getAsmPrinterFlags());
  28   const MachineFunction *MF = MI->getMF();
  29   for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
  30     const MachineOperand &MO = MI->getOperand(i);
  31     MCOperand MCOp;
  32     switch (MO.getType()) {
  33     default:
  34       llvm_unreachable("unknown operand type");
  35     case MachineOperand::MO_GlobalAddress: {
  36       Register FuncReg = MAI->getFuncReg(dyn_cast<Function>(MO.getGlobal()));
  37       if (!FuncReg.isValid()) {
  38         std::string DiagMsg;
  39         raw_string_ostream OS(DiagMsg);
  40         MI->print(OS);
  41         DiagMsg = "Unknown function in:" + DiagMsg;
  42         report_fatal_error(DiagMsg.c_str());
  43       }
  44       MCOp = MCOperand::createReg(FuncReg);
  45       break;
  46     }
  47     case MachineOperand::MO_MachineBasicBlock:
  48       MCOp = MCOperand::createReg(MAI->getOrCreateMBBRegister(*MO.getMBB()));
  49       break;
  50     case MachineOperand::MO_Register: {
  51       Register NewReg = MAI->getRegisterAlias(MF, MO.getReg());
  52       MCOp = MCOperand::createReg(NewReg.isValid() ? NewReg : MO.getReg());
  53       break;
  54     }
  55     case MachineOperand::MO_Immediate:
  56       if (MI->getOpcode() == SPIRV::OpExtInst && i == 2) {
  57         Register Reg = MAI->getExtInstSetReg(MO.getImm());
  58         MCOp = MCOperand::createReg(Reg);
  59       } else {
  60         MCOp = MCOperand::createImm(MO.getImm());
  61       }
  62       break;
  63     case MachineOperand::MO_FPImmediate:
  64       MCOp = MCOperand::createDFPImm(
  65           MO.getFPImm()->getValueAPF().convertToFloat());
  66       break;
  67     }
  68
  69     OutMI.addOperand(MCOp);
  70   }
  71 }