1 files changed, 115 insertions, 0 deletions
diff --git a/llvm/lib/Target/ARC/ARCMCInstLower.cpp b/llvm/lib/Target/ARC/ARCMCInstLower.cpp
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index 00000000000..4658388924e
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+++ b/llvm/lib/Target/ARC/ARCMCInstLower.cpp
@@ -0,0 +1,115 @@
+//===- ARCMCInstLower.cpp - ARC MachineInstr to MCInst ----------*- C++ -*-===//
+//
+//                     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 ARC MachineInstrs to their
+/// corresponding MCInst records.
+///
+//===----------------------------------------------------------------------===//
+
+#include "ARCMCInstLower.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineOperand.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCInst.h"
+
+using namespace llvm;
+
+ARCMCInstLower::ARCMCInstLower(MCContext *C, AsmPrinter &AsmPrinter)
+    : Ctx(C), Printer(AsmPrinter) {}
+
+MCOperand ARCMCInstLower::LowerSymbolOperand(const MachineOperand &MO,
+                                             MachineOperandType MOTy,
+                                             unsigned Offset) const {
+  MCSymbolRefExpr::VariantKind Kind = MCSymbolRefExpr::VK_None;
+  const MCSymbol *Symbol;
+
+  switch (MOTy) {
+  case MachineOperand::MO_MachineBasicBlock:
+    Symbol = MO.getMBB()->getSymbol();
+    break;
+  case MachineOperand::MO_GlobalAddress:
+    Symbol = Printer.getSymbol(MO.getGlobal());
+    Offset += MO.getOffset();
+    break;
+  case MachineOperand::MO_BlockAddress:
+    Symbol = Printer.GetBlockAddressSymbol(MO.getBlockAddress());
+    Offset += MO.getOffset();
+    break;
+  case MachineOperand::MO_ExternalSymbol:
+    Symbol = Printer.GetExternalSymbolSymbol(MO.getSymbolName());
+    Offset += MO.getOffset();
+    break;
+  case MachineOperand::MO_JumpTableIndex:
+    Symbol = Printer.GetJTISymbol(MO.getIndex());
+    break;
+  case MachineOperand::MO_ConstantPoolIndex:
+    Symbol = Printer.GetCPISymbol(MO.getIndex());
+    Offset += MO.getOffset();
+    break;
+  default:
+    llvm_unreachable("<unknown operand type>");
+  }
+
+  assert(Symbol && "Symbol creation failed.\n");
+  const MCSymbolRefExpr *MCSym = MCSymbolRefExpr::create(Symbol, Kind, *Ctx);
+
+  if (!Offset)
+    return MCOperand::createExpr(MCSym);
+
+  // Assume offset is never negative.
+  assert(Offset > 0);
+
+  const MCConstantExpr *OffsetExpr = MCConstantExpr::create(Offset, *Ctx);
+  const MCBinaryExpr *Add = MCBinaryExpr::createAdd(MCSym, OffsetExpr, *Ctx);
+  return MCOperand::createExpr(Add);
+}
+
+MCOperand ARCMCInstLower::LowerOperand(const MachineOperand &MO,
+                                       unsigned Offset) const {
+  MachineOperandType MOTy = MO.getType();
+
+  switch (MOTy) {
+  default:
+    llvm_unreachable("unknown operand type");
+  case MachineOperand::MO_Register:
+    // Ignore all implicit register operands.
+    if (MO.isImplicit())
+      break;
+    return MCOperand::createReg(MO.getReg());
+  case MachineOperand::MO_Immediate:
+    return MCOperand::createImm(MO.getImm() + Offset);
+  case MachineOperand::MO_MachineBasicBlock:
+  case MachineOperand::MO_GlobalAddress:
+  case MachineOperand::MO_ExternalSymbol:
+  case MachineOperand::MO_JumpTableIndex:
+  case MachineOperand::MO_ConstantPoolIndex:
+  case MachineOperand::MO_BlockAddress:
+    return LowerSymbolOperand(MO, MOTy, Offset);
+  case MachineOperand::MO_RegisterMask:
+    break;
+  }
+
+  return {};
+}
+
+void ARCMCInstLower::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 = LowerOperand(MO);
+
+    if (MCOp.isValid())
+      OutMI.addOperand(MCOp);
+  }
+}