1 //===-- MBLazeMCInstLower.cpp - Convert MBlaze MachineInstr to an MCInst---===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file contains code to lower MBlaze MachineInstrs to their corresponding
11 // MCInst records.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "MBlazeMCInstLower.h"
16 #include "MBlazeInstrInfo.h"
17 #include "llvm/Constants.h"
18 #include "llvm/CodeGen/AsmPrinter.h"
19 #include "llvm/CodeGen/MachineBasicBlock.h"
20 #include "llvm/CodeGen/MachineInstr.h"
21 #include "llvm/MC/MCAsmInfo.h"
22 #include "llvm/MC/MCContext.h"
23 #include "llvm/MC/MCExpr.h"
24 #include "llvm/MC/MCInst.h"
25 #include "llvm/Target/Mangler.h"
26 #include "llvm/Support/Debug.h"
27 #include "llvm/Support/raw_ostream.h"
28 #include "llvm/Support/ErrorHandling.h"
29 #include "llvm/ADT/SmallString.h"
30 using namespace llvm;
31
32 MCSymbol *MBlazeMCInstLower::
GetGlobalAddressSymbol(const MachineOperand & MO) const33 GetGlobalAddressSymbol(const MachineOperand &MO) const {
34 switch (MO.getTargetFlags()) {
35 default: llvm_unreachable("Unknown target flag on GV operand");
36 case 0: break;
37 }
38
39 return Printer.Mang->getSymbol(MO.getGlobal());
40 }
41
42 MCSymbol *MBlazeMCInstLower::
GetExternalSymbolSymbol(const MachineOperand & MO) const43 GetExternalSymbolSymbol(const MachineOperand &MO) const {
44 switch (MO.getTargetFlags()) {
45 default: llvm_unreachable("Unknown target flag on GV operand");
46 case 0: break;
47 }
48
49 return Printer.GetExternalSymbolSymbol(MO.getSymbolName());
50 }
51
52 MCSymbol *MBlazeMCInstLower::
GetJumpTableSymbol(const MachineOperand & MO) const53 GetJumpTableSymbol(const MachineOperand &MO) const {
54 SmallString<256> Name;
55 raw_svector_ostream(Name) << Printer.MAI->getPrivateGlobalPrefix() << "JTI"
56 << Printer.getFunctionNumber() << '_'
57 << MO.getIndex();
58 switch (MO.getTargetFlags()) {
59 default: llvm_unreachable("Unknown target flag on GV operand");
60 case 0: break;
61 }
62
63 // Create a symbol for the name.
64 return Ctx.GetOrCreateSymbol(Name.str());
65 }
66
67 MCSymbol *MBlazeMCInstLower::
GetConstantPoolIndexSymbol(const MachineOperand & MO) const68 GetConstantPoolIndexSymbol(const MachineOperand &MO) const {
69 SmallString<256> Name;
70 raw_svector_ostream(Name) << Printer.MAI->getPrivateGlobalPrefix() << "CPI"
71 << Printer.getFunctionNumber() << '_'
72 << MO.getIndex();
73
74 switch (MO.getTargetFlags()) {
75 default:
76 llvm_unreachable("Unknown target flag on GV operand");
77
78 case 0: break;
79 }
80
81 // Create a symbol for the name.
82 return Ctx.GetOrCreateSymbol(Name.str());
83 }
84
85 MCSymbol *MBlazeMCInstLower::
GetBlockAddressSymbol(const MachineOperand & MO) const86 GetBlockAddressSymbol(const MachineOperand &MO) const {
87 switch (MO.getTargetFlags()) {
88 default:
89 assert(0 && "Unknown target flag on GV operand");
90
91 case 0: break;
92 }
93
94 return Printer.GetBlockAddressSymbol(MO.getBlockAddress());
95 }
96
97 MCOperand MBlazeMCInstLower::
LowerSymbolOperand(const MachineOperand & MO,MCSymbol * Sym) const98 LowerSymbolOperand(const MachineOperand &MO, MCSymbol *Sym) const {
99 // FIXME: We would like an efficient form for this, so we don't have to do a
100 // lot of extra uniquing.
101 const MCExpr *Expr = MCSymbolRefExpr::Create(Sym, Ctx);
102
103 switch (MO.getTargetFlags()) {
104 default:
105 llvm_unreachable("Unknown target flag on GV operand");
106
107 case 0: break;
108 }
109
110 if (!MO.isJTI() && MO.getOffset())
111 Expr = MCBinaryExpr::CreateAdd(Expr,
112 MCConstantExpr::Create(MO.getOffset(), Ctx),
113 Ctx);
114 return MCOperand::CreateExpr(Expr);
115 }
116
Lower(const MachineInstr * MI,MCInst & OutMI) const117 void MBlazeMCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
118 OutMI.setOpcode(MI->getOpcode());
119
120 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
121 const MachineOperand &MO = MI->getOperand(i);
122
123 MCOperand MCOp;
124 switch (MO.getType()) {
125 default: llvm_unreachable("unknown operand type");
126 case MachineOperand::MO_Register:
127 // Ignore all implicit register operands.
128 if (MO.isImplicit()) continue;
129 MCOp = MCOperand::CreateReg(MO.getReg());
130 break;
131 case MachineOperand::MO_Immediate:
132 MCOp = MCOperand::CreateImm(MO.getImm());
133 break;
134 case MachineOperand::MO_MachineBasicBlock:
135 MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create(
136 MO.getMBB()->getSymbol(), Ctx));
137 break;
138 case MachineOperand::MO_GlobalAddress:
139 MCOp = LowerSymbolOperand(MO, GetGlobalAddressSymbol(MO));
140 break;
141 case MachineOperand::MO_ExternalSymbol:
142 MCOp = LowerSymbolOperand(MO, GetExternalSymbolSymbol(MO));
143 break;
144 case MachineOperand::MO_JumpTableIndex:
145 MCOp = LowerSymbolOperand(MO, GetJumpTableSymbol(MO));
146 break;
147 case MachineOperand::MO_ConstantPoolIndex:
148 MCOp = LowerSymbolOperand(MO, GetConstantPoolIndexSymbol(MO));
149 break;
150 case MachineOperand::MO_BlockAddress:
151 MCOp = LowerSymbolOperand(MO, GetBlockAddressSymbol(MO));
152 break;
153 case MachineOperand::MO_FPImmediate:
154 bool ignored;
155 APFloat FVal = MO.getFPImm()->getValueAPF();
156 FVal.convert(APFloat::IEEEsingle, APFloat::rmTowardZero, &ignored);
157
158 APInt IVal = FVal.bitcastToAPInt();
159 uint64_t Val = *IVal.getRawData();
160 MCOp = MCOperand::CreateImm(Val);
161 break;
162 }
163
164 OutMI.addOperand(MCOp);
165 }
166 }
167