llvm/lib/Target/AVR/AVRMCInstLower.cpp

   1 //===-- AVRMCInstLower.cpp - Convert AVR MachineInstr to an MCInst --------===//
   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 AVR MachineInstrs to their corresponding
  10 // MCInst records.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "AVRMCInstLower.h"
  15 #include "AVRInstrInfo.h"
  16 #include "MCTargetDesc/AVRMCExpr.h"
  17
  18 #include "llvm/CodeGen/AsmPrinter.h"
  19 #include "llvm/IR/Mangler.h"
  20 #include "llvm/MC/MCInst.h"
  21 #include "llvm/Support/ErrorHandling.h"
  22
  23 namespace llvm {
  24
  25 MCOperand
  26 AVRMCInstLower::lowerSymbolOperand(const MachineOperand &MO, MCSymbol *Sym,
  27                                    const AVRSubtarget &Subtarget) const {
  28   unsigned char TF = MO.getTargetFlags();
  29   const MCExpr *Expr = MCSymbolRefExpr::create(Sym, Ctx);
  30
  31   bool IsNegated = false;
  32   if (TF & AVRII::MO_NEG) {
  33     IsNegated = true;
  34   }
  35
  36   if (!MO.isJTI() && MO.getOffset()) {
  37     Expr = MCBinaryExpr::createAdd(
  38         Expr, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);
  39   }
  40
  41   bool IsFunction = MO.isGlobal() && isa<Function>(MO.getGlobal());
  42
  43   if (TF & AVRII::MO_LO) {
  44     if (IsFunction) {
  45       Expr =
  46           AVRMCExpr::create(Subtarget.hasEIJMPCALL() ? AVRMCExpr::VK_AVR_LO8_GS
  47                                                      : AVRMCExpr::VK_AVR_PM_LO8,
  48                             Expr, IsNegated, Ctx);
  49     } else {
  50       Expr = AVRMCExpr::create(AVRMCExpr::VK_AVR_LO8, Expr, IsNegated, Ctx);
  51     }
  52   } else if (TF & AVRII::MO_HI) {
  53     if (IsFunction) {
  54       Expr =
  55           AVRMCExpr::create(Subtarget.hasEIJMPCALL() ? AVRMCExpr::VK_AVR_HI8_GS
  56                                                      : AVRMCExpr::VK_AVR_PM_HI8,
  57                             Expr, IsNegated, Ctx);
  58     } else {
  59       Expr = AVRMCExpr::create(AVRMCExpr::VK_AVR_HI8, Expr, IsNegated, Ctx);
  60     }
  61   } else if (TF != 0) {
  62     llvm_unreachable("Unknown target flag on symbol operand");
  63   }
  64
  65   return MCOperand::createExpr(Expr);
  66 }
  67
  68 void AVRMCInstLower::lowerInstruction(const MachineInstr &MI,
  69                                       MCInst &OutMI) const {
  70   auto &Subtarget = MI.getParent()->getParent()->getSubtarget<AVRSubtarget>();
  71   OutMI.setOpcode(MI.getOpcode());
  72
  73   for (MachineOperand const &MO : MI.operands()) {
  74     MCOperand MCOp;
  75
  76     switch (MO.getType()) {
  77     default:
  78       MI.print(errs());
  79       llvm_unreachable("unknown operand type");
  80     case MachineOperand::MO_Register:
  81       // Ignore all implicit register operands.
  82       if (MO.isImplicit())
  83         continue;
  84       MCOp = MCOperand::createReg(MO.getReg());
  85       break;
  86     case MachineOperand::MO_Immediate:
  87       MCOp = MCOperand::createImm(MO.getImm());
  88       break;
  89     case MachineOperand::MO_GlobalAddress:
  90       MCOp =
  91           lowerSymbolOperand(MO, Printer.getSymbol(MO.getGlobal()), Subtarget);
  92       break;
  93     case MachineOperand::MO_ExternalSymbol:
  94       MCOp = lowerSymbolOperand(
  95           MO, Printer.GetExternalSymbolSymbol(MO.getSymbolName()), Subtarget);
  96       break;
  97     case MachineOperand::MO_MachineBasicBlock:
  98       MCOp = MCOperand::createExpr(
  99           MCSymbolRefExpr::create(MO.getMBB()->getSymbol(), Ctx));
 100       break;
 101     case MachineOperand::MO_RegisterMask:
 102       continue;
 103     case MachineOperand::MO_BlockAddress:
 104       MCOp = lowerSymbolOperand(
 105           MO, Printer.GetBlockAddressSymbol(MO.getBlockAddress()), Subtarget);
 106       break;
 107     case MachineOperand::MO_JumpTableIndex:
 108       MCOp = lowerSymbolOperand(MO, Printer.GetJTISymbol(MO.getIndex()),
 109                                 Subtarget);
 110       break;
 111     case MachineOperand::MO_ConstantPoolIndex:
 112       MCOp = lowerSymbolOperand(MO, Printer.GetCPISymbol(MO.getIndex()),
 113                                 Subtarget);
 114       break;
 115     }
 116
 117     OutMI.addOperand(MCOp);
 118   }
 119 }
 120
 121 } // end of namespace llvm