1 //===- HexagonMCInstLower.cpp - Convert Hexagon 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 Hexagon MachineInstrs to their corresponding
11 // MCInst records.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "Hexagon.h"
16 #include "HexagonAsmPrinter.h"
17 #include "MCTargetDesc/HexagonMCExpr.h"
18 #include "MCTargetDesc/HexagonMCInstrInfo.h"
19 #include "MCTargetDesc/HexagonMCTargetDesc.h"
20 #include "llvm/ADT/APFloat.h"
21 #include "llvm/ADT/APInt.h"
22 #include "llvm/CodeGen/MachineBasicBlock.h"
23 #include "llvm/CodeGen/MachineInstr.h"
24 #include "llvm/CodeGen/MachineOperand.h"
25 #include "llvm/IR/Constants.h"
26 #include "llvm/MC/MCContext.h"
27 #include "llvm/MC/MCExpr.h"
28 #include "llvm/MC/MCInst.h"
29 #include "llvm/Support/ErrorHandling.h"
30 #include "llvm/Support/raw_ostream.h"
31 #include <cassert>
32 
33 using namespace llvm;
34 
35 namespace llvm {
36 
37 void HexagonLowerToMC(const MCInstrInfo &MCII, const MachineInstr *MI,
38                       MCInst &MCB, HexagonAsmPrinter &AP);
39 
40 } // end namespace llvm
41 
GetSymbolRef(const MachineOperand & MO,const MCSymbol * Symbol,HexagonAsmPrinter & Printer,bool MustExtend)42 static MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol,
43                               HexagonAsmPrinter &Printer, bool MustExtend) {
44   MCContext &MC = Printer.OutContext;
45   const MCExpr *ME;
46 
47   // Populate the relocation type based on Hexagon target flags
48   // set on an operand
49   MCSymbolRefExpr::VariantKind RelocationType;
50   switch (MO.getTargetFlags() & ~HexagonII::HMOTF_ConstExtended) {
51   default:
52     RelocationType = MCSymbolRefExpr::VK_None;
53     break;
54   case HexagonII::MO_PCREL:
55     RelocationType = MCSymbolRefExpr::VK_Hexagon_PCREL;
56     break;
57   case HexagonII::MO_GOT:
58     RelocationType = MCSymbolRefExpr::VK_GOT;
59     break;
60   case HexagonII::MO_LO16:
61     RelocationType = MCSymbolRefExpr::VK_Hexagon_LO16;
62     break;
63   case HexagonII::MO_HI16:
64     RelocationType = MCSymbolRefExpr::VK_Hexagon_HI16;
65     break;
66   case HexagonII::MO_GPREL:
67     RelocationType = MCSymbolRefExpr::VK_Hexagon_GPREL;
68     break;
69   case HexagonII::MO_GDGOT:
70     RelocationType = MCSymbolRefExpr::VK_Hexagon_GD_GOT;
71     break;
72   case HexagonII::MO_GDPLT:
73     RelocationType = MCSymbolRefExpr::VK_Hexagon_GD_PLT;
74     break;
75   case HexagonII::MO_IE:
76     RelocationType = MCSymbolRefExpr::VK_Hexagon_IE;
77     break;
78   case HexagonII::MO_IEGOT:
79     RelocationType = MCSymbolRefExpr::VK_Hexagon_IE_GOT;
80     break;
81   case HexagonII::MO_TPREL:
82     RelocationType = MCSymbolRefExpr::VK_TPREL;
83     break;
84   }
85 
86   ME = MCSymbolRefExpr::create(Symbol, RelocationType, MC);
87 
88   if (!MO.isJTI() && MO.getOffset())
89     ME = MCBinaryExpr::createAdd(ME, MCConstantExpr::create(MO.getOffset(), MC),
90                                  MC);
91 
92   ME = HexagonMCExpr::create(ME, MC);
93   HexagonMCInstrInfo::setMustExtend(*ME, MustExtend);
94   return MCOperand::createExpr(ME);
95 }
96 
97 // Create an MCInst from a MachineInstr
HexagonLowerToMC(const MCInstrInfo & MCII,const MachineInstr * MI,MCInst & MCB,HexagonAsmPrinter & AP)98 void llvm::HexagonLowerToMC(const MCInstrInfo &MCII, const MachineInstr *MI,
99                             MCInst &MCB, HexagonAsmPrinter &AP) {
100   if (MI->getOpcode() == Hexagon::ENDLOOP0) {
101     HexagonMCInstrInfo::setInnerLoop(MCB);
102     return;
103   }
104   if (MI->getOpcode() == Hexagon::ENDLOOP1) {
105     HexagonMCInstrInfo::setOuterLoop(MCB);
106     return;
107   }
108   MCInst *MCI = new (AP.OutContext) MCInst;
109   MCI->setOpcode(MI->getOpcode());
110   assert(MCI->getOpcode() == static_cast<unsigned>(MI->getOpcode()) &&
111          "MCI opcode should have been set on construction");
112 
113   for (unsigned i = 0, e = MI->getNumOperands(); i < e; i++) {
114     const MachineOperand &MO = MI->getOperand(i);
115     MCOperand MCO;
116     bool MustExtend = MO.getTargetFlags() & HexagonII::HMOTF_ConstExtended;
117 
118     switch (MO.getType()) {
119     default:
120       MI->print(errs());
121       llvm_unreachable("unknown operand type");
122     case MachineOperand::MO_RegisterMask:
123       continue;
124     case MachineOperand::MO_Register:
125       // Ignore all implicit register operands.
126       if (MO.isImplicit())
127         continue;
128       MCO = MCOperand::createReg(MO.getReg());
129       break;
130     case MachineOperand::MO_FPImmediate: {
131       APFloat Val = MO.getFPImm()->getValueAPF();
132       // FP immediates are used only when setting GPRs, so they may be dealt
133       // with like regular immediates from this point on.
134       auto Expr = HexagonMCExpr::create(
135           MCConstantExpr::create(*Val.bitcastToAPInt().getRawData(),
136                                  AP.OutContext),
137           AP.OutContext);
138       HexagonMCInstrInfo::setMustExtend(*Expr, MustExtend);
139       MCO = MCOperand::createExpr(Expr);
140       break;
141     }
142     case MachineOperand::MO_Immediate: {
143       auto Expr = HexagonMCExpr::create(
144           MCConstantExpr::create(MO.getImm(), AP.OutContext), AP.OutContext);
145       HexagonMCInstrInfo::setMustExtend(*Expr, MustExtend);
146       MCO = MCOperand::createExpr(Expr);
147       break;
148     }
149     case MachineOperand::MO_MachineBasicBlock: {
150       MCExpr const *Expr = MCSymbolRefExpr::create(MO.getMBB()->getSymbol(),
151                                                    AP.OutContext);
152       Expr = HexagonMCExpr::create(Expr, AP.OutContext);
153       HexagonMCInstrInfo::setMustExtend(*Expr, MustExtend);
154       MCO = MCOperand::createExpr(Expr);
155       break;
156     }
157     case MachineOperand::MO_GlobalAddress:
158       MCO = GetSymbolRef(MO, AP.getSymbol(MO.getGlobal()), AP, MustExtend);
159       break;
160     case MachineOperand::MO_ExternalSymbol:
161       MCO = GetSymbolRef(MO, AP.GetExternalSymbolSymbol(MO.getSymbolName()),
162                          AP, MustExtend);
163       break;
164     case MachineOperand::MO_JumpTableIndex:
165       MCO = GetSymbolRef(MO, AP.GetJTISymbol(MO.getIndex()), AP, MustExtend);
166       break;
167     case MachineOperand::MO_ConstantPoolIndex:
168       MCO = GetSymbolRef(MO, AP.GetCPISymbol(MO.getIndex()), AP, MustExtend);
169       break;
170     case MachineOperand::MO_BlockAddress:
171       MCO = GetSymbolRef(MO, AP.GetBlockAddressSymbol(MO.getBlockAddress()), AP,
172                          MustExtend);
173       break;
174     }
175 
176     MCI->addOperand(MCO);
177   }
178   AP.HexagonProcessInstruction(*MCI, *MI);
179   HexagonMCInstrInfo::extendIfNeeded(AP.OutContext, MCII, MCB, *MCI);
180   MCB.addOperand(MCOperand::createInst(MCI));
181 }
182