LLVM  10.0.0svn
SystemZMCInstLower.cpp
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1 //===-- SystemZMCInstLower.cpp - Lower MachineInstr to 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 #include "SystemZMCInstLower.h"
10 #include "SystemZAsmPrinter.h"
11 #include "llvm/IR/Mangler.h"
12 #include "llvm/MC/MCExpr.h"
13 #include "llvm/MC/MCInst.h"
14 #include "llvm/MC/MCStreamer.h"
15 
16 using namespace llvm;
17 
18 // Return the VK_* enumeration for MachineOperand target flags Flags.
20  switch (Flags & SystemZII::MO_SYMBOL_MODIFIER) {
21  case 0:
23  case SystemZII::MO_GOT:
27  }
28  llvm_unreachable("Unrecognised MO_ACCESS_MODEL");
29 }
30 
32  SystemZAsmPrinter &asmprinter)
33  : Ctx(ctx), AsmPrinter(asmprinter) {}
34 
35 const MCExpr *
38  const MCSymbol *Symbol;
39  bool HasOffset = true;
40  switch (MO.getType()) {
42  Symbol = MO.getMBB()->getSymbol();
43  HasOffset = false;
44  break;
45 
47  Symbol = AsmPrinter.getSymbol(MO.getGlobal());
48  break;
49 
52  break;
53 
55  Symbol = AsmPrinter.GetJTISymbol(MO.getIndex());
56  HasOffset = false;
57  break;
58 
60  Symbol = AsmPrinter.GetCPISymbol(MO.getIndex());
61  break;
62 
65  break;
66 
67  default:
68  llvm_unreachable("unknown operand type");
69  }
70  const MCExpr *Expr = MCSymbolRefExpr::create(Symbol, Kind, Ctx);
71  if (HasOffset)
72  if (int64_t Offset = MO.getOffset()) {
73  const MCExpr *OffsetExpr = MCConstantExpr::create(Offset, Ctx);
74  Expr = MCBinaryExpr::createAdd(Expr, OffsetExpr, Ctx);
75  }
76  return Expr;
77 }
78 
80  switch (MO.getType()) {
82  return MCOperand::createReg(MO.getReg());
83 
85  return MCOperand::createImm(MO.getImm());
86 
87  default: {
89  return MCOperand::createExpr(getExpr(MO, Kind));
90  }
91  }
92 }
93 
94 void SystemZMCInstLower::lower(const MachineInstr *MI, MCInst &OutMI) const {
95  OutMI.setOpcode(MI->getOpcode());
96  for (unsigned I = 0, E = MI->getNumOperands(); I != E; ++I) {
97  const MachineOperand &MO = MI->getOperand(I);
98  // Ignore all implicit register operands.
99  if (!MO.isReg() || !MO.isImplicit())
100  OutMI.addOperand(lowerOperand(MO));
101  }
102 }
unsigned getTargetFlags() const
MachineBasicBlock * getMBB() const
MCSymbol * GetExternalSymbolSymbol(StringRef Sym) const
Return the MCSymbol for the specified ExternalSymbol.
static const MCSymbolRefExpr * create(const MCSymbol *Symbol, MCContext &Ctx)
Definition: MCExpr.h:331
This class represents lattice values for constants.
Definition: AllocatorList.h:23
MCSymbol - Instances of this class represent a symbol name in the MC file, and MCSymbols are created ...
Definition: MCSymbol.h:41
static MCOperand createExpr(const MCExpr *Val)
Definition: MCInst.h:136
Address of indexed Jump Table for switch.
MachineBasicBlock reference.
void lower(const MachineInstr *MI, MCInst &OutMI) const
static MCOperand createReg(unsigned Reg)
Definition: MCInst.h:115
unsigned getNumOperands() const
Retuns the total number of operands.
Definition: MachineInstr.h:414
static MCSymbolRefExpr::VariantKind getVariantKind(unsigned Flags)
Base class for the full range of assembler expressions which are needed for parsing.
Definition: MCExpr.h:35
Name of external global symbol.
unsigned getOpcode() const
Returns the opcode of this MachineInstr.
Definition: MachineInstr.h:411
const char * getSymbolName() const
Context object for machine code objects.
Definition: MCContext.h:65
SystemZMCInstLower(MCContext &ctx, SystemZAsmPrinter &asmPrinter)
static const MCBinaryExpr * createAdd(const MCExpr *LHS, const MCExpr *RHS, MCContext &Ctx)
Definition: MCExpr.h:469
Instances of this class represent a single low-level machine instruction.
Definition: MCInst.h:158
static const MCConstantExpr * create(int64_t Value, MCContext &Ctx, bool PrintInHex=false)
Definition: MCExpr.cpp:169
MCOperand lowerOperand(const MachineOperand &MO) const
Address of a global value.
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
const GlobalValue * getGlobal() const
This class is intended to be used as a driving class for all asm writers.
Definition: AsmPrinter.h:78
Address of a basic block.
virtual MCSymbol * GetCPISymbol(unsigned CPID) const
Return the symbol for the specified constant pool entry.
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
void setOpcode(unsigned Op)
Definition: MCInst.h:170
MCSymbol * GetBlockAddressSymbol(const BlockAddress *BA) const
Return the MCSymbol used to satisfy BlockAddress uses of the specified basic block.
MCSymbol * getSymbol(const GlobalValue *GV) const
Definition: AsmPrinter.cpp:443
MachineOperand class - Representation of each machine instruction operand.
int64_t getImm() const
Representation of each machine instruction.
Definition: MachineInstr.h:64
MCSymbol * GetJTISymbol(unsigned JTID, bool isLinkerPrivate=false) const
Return the symbol for the specified jump table entry.
int64_t getOffset() const
Return the offset from the symbol in this operand.
const BlockAddress * getBlockAddress() const
MCSymbol * getSymbol() const
Return the MCSymbol for this basic block.
#define I(x, y, z)
Definition: MD5.cpp:58
bool isReg() const
isReg - Tests if this is a MO_Register operand.
IRTranslator LLVM IR MI
void addOperand(const MCOperand &Op)
Definition: MCInst.h:183
Address of indexed Constant in Constant Pool.
Register getReg() const
getReg - Returns the register number.
const MachineOperand & getOperand(unsigned i) const
Definition: MachineInstr.h:416
Instances of this class represent operands of the MCInst class.
Definition: MCInst.h:34
MachineOperandType getType() const
getType - Returns the MachineOperandType for this operand.
static MCOperand createImm(int64_t Val)
Definition: MCInst.h:122
const MCExpr * getExpr(const MachineOperand &MO, MCSymbolRefExpr::VariantKind Kind) const
bool isImplicit() const