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.
getVariantKind(unsigned Flags)19 static MCSymbolRefExpr::VariantKind getVariantKind(unsigned Flags) {
20 switch (Flags & SystemZII::MO_SYMBOL_MODIFIER) {
21 case 0:
22 return MCSymbolRefExpr::VK_None;
23 case SystemZII::MO_GOT:
24 return MCSymbolRefExpr::VK_GOT;
25 case SystemZII::MO_INDNTPOFF:
26 return MCSymbolRefExpr::VK_INDNTPOFF;
27 }
28 llvm_unreachable("Unrecognised MO_ACCESS_MODEL");
29 }
30
SystemZMCInstLower(MCContext & ctx,SystemZAsmPrinter & asmprinter)31 SystemZMCInstLower::SystemZMCInstLower(MCContext &ctx,
32 SystemZAsmPrinter &asmprinter)
33 : Ctx(ctx), AsmPrinter(asmprinter) {}
34
35 const MCExpr *
getExpr(const MachineOperand & MO,MCSymbolRefExpr::VariantKind Kind) const36 SystemZMCInstLower::getExpr(const MachineOperand &MO,
37 MCSymbolRefExpr::VariantKind Kind) 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(MO.getGlobal());
48 break;
49
50 case MachineOperand::MO_ExternalSymbol:
51 Symbol = AsmPrinter.GetExternalSymbolSymbol(MO.getSymbolName());
52 break;
53
54 case MachineOperand::MO_JumpTableIndex:
55 Symbol = AsmPrinter.GetJTISymbol(MO.getIndex());
56 HasOffset = false;
57 break;
58
59 case MachineOperand::MO_ConstantPoolIndex:
60 Symbol = AsmPrinter.GetCPISymbol(MO.getIndex());
61 break;
62
63 case MachineOperand::MO_BlockAddress:
64 Symbol = AsmPrinter.GetBlockAddressSymbol(MO.getBlockAddress());
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
lowerOperand(const MachineOperand & MO) const79 MCOperand SystemZMCInstLower::lowerOperand(const MachineOperand &MO) const {
80 switch (MO.getType()) {
81 case MachineOperand::MO_Register:
82 return MCOperand::createReg(MO.getReg());
83
84 case MachineOperand::MO_Immediate:
85 return MCOperand::createImm(MO.getImm());
86
87 default: {
88 MCSymbolRefExpr::VariantKind Kind = getVariantKind(MO.getTargetFlags());
89 return MCOperand::createExpr(getExpr(MO, Kind));
90 }
91 }
92 }
93
lower(const MachineInstr * MI,MCInst & OutMI) const94 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 }
103