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 "MCTargetDesc/SystemZMCAsmInfo.h"
11#include "SystemZAsmPrinter.h"
12#include "llvm/IR/Mangler.h"
13#include "llvm/MC/MCExpr.h"
14#include "llvm/MC/MCInst.h"
15#include "llvm/MC/MCStreamer.h"
16
17using namespace llvm;
18
19// Return the S_* enumeration for MachineOperand target flags Flags.
20static SystemZ::Specifier getSpecifierForTFlags(unsigned Flags) {
21 switch (Flags & SystemZII::MO_SYMBOL_MODIFIER) {
22 case 0:
23 return SystemZ::S_None;
24 case SystemZII::MO_GOT:
25 return SystemZ::S_GOT;
26 case SystemZII::MO_INDNTPOFF:
27 return SystemZ::S_INDNTPOFF;
28 }
29 llvm_unreachable("Unrecognised MO_ACCESS_MODEL");
30}
31
32SystemZMCInstLower::SystemZMCInstLower(MCContext &ctx,
33 SystemZAsmPrinter &asmprinter)
34 : Ctx(ctx), AsmPrinter(asmprinter) {}
35
36const MCExpr *SystemZMCInstLower::getExpr(const MachineOperand &MO,
37 SystemZ::Specifier Spec) const {
38 const MCSymbol *Symbol;
39 bool HasOffset = true;
40 switch (MO.getType()) {
41 case MachineOperand::MO_MachineBasicBlock:
42 Symbol = MO.getMBB()->getSymbol();
43 HasOffset = false;
44 break;
45
46 case MachineOperand::MO_GlobalAddress:
47 Symbol = AsmPrinter.getSymbol(GV: MO.getGlobal());
48 break;
49
50 case MachineOperand::MO_ExternalSymbol:
51 Symbol = AsmPrinter.GetExternalSymbolSymbol(Sym: MO.getSymbolName());
52 break;
53
54 case MachineOperand::MO_JumpTableIndex:
55 Symbol = AsmPrinter.GetJTISymbol(JTID: MO.getIndex());
56 HasOffset = false;
57 break;
58
59 case MachineOperand::MO_ConstantPoolIndex:
60 Symbol = AsmPrinter.GetCPISymbol(CPID: MO.getIndex());
61 break;
62
63 case MachineOperand::MO_BlockAddress:
64 Symbol = AsmPrinter.GetBlockAddressSymbol(BA: MO.getBlockAddress());
65 break;
66
67 default:
68 llvm_unreachable("unknown operand type");
69 }
70 const MCExpr *Expr = MCSymbolRefExpr::create(Symbol, specifier: Spec, Ctx);
71 if (HasOffset)
72 if (int64_t Offset = MO.getOffset()) {
73 const MCExpr *OffsetExpr = MCConstantExpr::create(Value: Offset, Ctx);
74 Expr = MCBinaryExpr::createAdd(LHS: Expr, RHS: OffsetExpr, Ctx);
75 }
76 return Expr;
77}
78
79MCOperand SystemZMCInstLower::lowerOperand(const MachineOperand &MO) const {
80 switch (MO.getType()) {
81 case MachineOperand::MO_Register:
82 return MCOperand::createReg(Reg: MO.getReg());
83
84 case MachineOperand::MO_Immediate:
85 return MCOperand::createImm(Val: MO.getImm());
86
87 default: {
88 auto Kind = getSpecifierForTFlags(Flags: MO.getTargetFlags());
89 return MCOperand::createExpr(Val: getExpr(MO, Spec: Kind));
90 }
91 }
92}
93
94void SystemZMCInstLower::lower(const MachineInstr *MI, MCInst &OutMI) const {
95 OutMI.setOpcode(MI->getOpcode());
96 for (const MachineOperand &MO : MI->operands())
97 // Ignore all implicit register operands.
98 if (!MO.isReg() || !MO.isImplicit())
99 OutMI.addOperand(Op: lowerOperand(MO));
100}
101