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/ADT/SmallString.h"
18 #include "llvm/CodeGen/AsmPrinter.h"
19 #include "llvm/CodeGen/MachineBasicBlock.h"
20 #include "llvm/CodeGen/MachineInstr.h"
21 #include "llvm/IR/Constants.h"
22 #include "llvm/MC/MCAsmInfo.h"
23 #include "llvm/MC/MCContext.h"
24 #include "llvm/MC/MCExpr.h"
25 #include "llvm/MC/MCInst.h"
26 #include "llvm/Support/Debug.h"
27 #include "llvm/Support/ErrorHandling.h"
28 #include "llvm/Support/raw_ostream.h"
29 #include "llvm/Target/Mangler.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: llvm_unreachable("Unknown target flag on GV operand");
89 case 0: break;
90 }
91
92 return Printer.GetBlockAddressSymbol(MO.getBlockAddress());
93 }
94
95 MCOperand MBlazeMCInstLower::
LowerSymbolOperand(const MachineOperand & MO,MCSymbol * Sym) const96 LowerSymbolOperand(const MachineOperand &MO, MCSymbol *Sym) const {
97 // FIXME: We would like an efficient form for this, so we don't have to do a
98 // lot of extra uniquing.
99 const MCExpr *Expr = MCSymbolRefExpr::Create(Sym, Ctx);
100
101 switch (MO.getTargetFlags()) {
102 default:
103 llvm_unreachable("Unknown target flag on GV operand");
104
105 case 0: break;
106 }
107
108 if (!MO.isJTI() && MO.getOffset())
109 Expr = MCBinaryExpr::CreateAdd(Expr,
110 MCConstantExpr::Create(MO.getOffset(), Ctx),
111 Ctx);
112 return MCOperand::CreateExpr(Expr);
113 }
114
Lower(const MachineInstr * MI,MCInst & OutMI) const115 void MBlazeMCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
116 OutMI.setOpcode(MI->getOpcode());
117
118 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
119 const MachineOperand &MO = MI->getOperand(i);
120
121 MCOperand MCOp;
122 switch (MO.getType()) {
123 default: llvm_unreachable("unknown operand type");
124 case MachineOperand::MO_Register:
125 // Ignore all implicit register operands.
126 if (MO.isImplicit()) continue;
127 MCOp = MCOperand::CreateReg(MO.getReg());
128 break;
129 case MachineOperand::MO_Immediate:
130 MCOp = MCOperand::CreateImm(MO.getImm());
131 break;
132 case MachineOperand::MO_MachineBasicBlock:
133 MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create(
134 MO.getMBB()->getSymbol(), Ctx));
135 break;
136 case MachineOperand::MO_GlobalAddress:
137 MCOp = LowerSymbolOperand(MO, GetGlobalAddressSymbol(MO));
138 break;
139 case MachineOperand::MO_ExternalSymbol:
140 MCOp = LowerSymbolOperand(MO, GetExternalSymbolSymbol(MO));
141 break;
142 case MachineOperand::MO_JumpTableIndex:
143 MCOp = LowerSymbolOperand(MO, GetJumpTableSymbol(MO));
144 break;
145 case MachineOperand::MO_ConstantPoolIndex:
146 MCOp = LowerSymbolOperand(MO, GetConstantPoolIndexSymbol(MO));
147 break;
148 case MachineOperand::MO_BlockAddress:
149 MCOp = LowerSymbolOperand(MO, GetBlockAddressSymbol(MO));
150 break;
151 case MachineOperand::MO_FPImmediate: {
152 bool ignored;
153 APFloat FVal = MO.getFPImm()->getValueAPF();
154 FVal.convert(APFloat::IEEEsingle, APFloat::rmTowardZero, &ignored);
155
156 APInt IVal = FVal.bitcastToAPInt();
157 uint64_t Val = *IVal.getRawData();
158 MCOp = MCOperand::CreateImm(Val);
159 break;
160 }
161 case MachineOperand::MO_RegisterMask:
162 continue;
163 }
164
165 OutMI.addOperand(MCOp);
166 }
167 }
168