1 //===-- HexagonAsmPrinter.cpp - Print machine instrs to Hexagon assembly --===//
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 a printer that converts from our internal representation
11 // of machine-dependent LLVM code to Hexagon assembly language. This printer is
12 // the output mechanism used by `llc'.
13 //
14 //===----------------------------------------------------------------------===//
15
16 #include "Hexagon.h"
17 #include "HexagonAsmPrinter.h"
18 #include "HexagonMachineFunctionInfo.h"
19 #include "HexagonSubtarget.h"
20 #include "HexagonTargetMachine.h"
21 #include "MCTargetDesc/HexagonInstPrinter.h"
22 #include "MCTargetDesc/HexagonMCInstrInfo.h"
23 #include "llvm/ADT/SmallString.h"
24 #include "llvm/ADT/SmallVector.h"
25 #include "llvm/ADT/StringExtras.h"
26 #include "llvm/Analysis/ConstantFolding.h"
27 #include "llvm/CodeGen/AsmPrinter.h"
28 #include "llvm/CodeGen/MachineFunctionPass.h"
29 #include "llvm/CodeGen/MachineInstr.h"
30 #include "llvm/CodeGen/MachineInstrBuilder.h"
31 #include "llvm/CodeGen/MachineModuleInfo.h"
32 #include "llvm/IR/Constants.h"
33 #include "llvm/IR/DataLayout.h"
34 #include "llvm/IR/DerivedTypes.h"
35 #include "llvm/IR/Mangler.h"
36 #include "llvm/IR/Module.h"
37 #include "llvm/MC/MCAsmInfo.h"
38 #include "llvm/MC/MCContext.h"
39 #include "llvm/MC/MCExpr.h"
40 #include "llvm/MC/MCInst.h"
41 #include "llvm/MC/MCSection.h"
42 #include "llvm/MC/MCStreamer.h"
43 #include "llvm/MC/MCSymbol.h"
44 #include "llvm/Support/CommandLine.h"
45 #include "llvm/Support/Compiler.h"
46 #include "llvm/Support/Debug.h"
47 #include "llvm/Support/Format.h"
48 #include "llvm/Support/MathExtras.h"
49 #include "llvm/Support/TargetRegistry.h"
50 #include "llvm/Support/raw_ostream.h"
51 #include "llvm/Target/TargetInstrInfo.h"
52 #include "llvm/Target/TargetLoweringObjectFile.h"
53 #include "llvm/Target/TargetOptions.h"
54 #include "llvm/Target/TargetRegisterInfo.h"
55
56 using namespace llvm;
57
58 #define DEBUG_TYPE "asm-printer"
59
60 static cl::opt<bool> AlignCalls(
61 "hexagon-align-calls", cl::Hidden, cl::init(true),
62 cl::desc("Insert falign after call instruction for Hexagon target"));
63
HexagonAsmPrinter(TargetMachine & TM,std::unique_ptr<MCStreamer> Streamer)64 HexagonAsmPrinter::HexagonAsmPrinter(TargetMachine &TM,
65 std::unique_ptr<MCStreamer> Streamer)
66 : AsmPrinter(TM, std::move(Streamer)), Subtarget(nullptr) {}
67
printOperand(const MachineInstr * MI,unsigned OpNo,raw_ostream & O)68 void HexagonAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
69 raw_ostream &O) {
70 const MachineOperand &MO = MI->getOperand(OpNo);
71
72 switch (MO.getType()) {
73 default: llvm_unreachable ("<unknown operand type>");
74 case MachineOperand::MO_Register:
75 O << HexagonInstPrinter::getRegisterName(MO.getReg());
76 return;
77 case MachineOperand::MO_Immediate:
78 O << MO.getImm();
79 return;
80 case MachineOperand::MO_MachineBasicBlock:
81 O << *MO.getMBB()->getSymbol();
82 return;
83 case MachineOperand::MO_ConstantPoolIndex:
84 O << *GetCPISymbol(MO.getIndex());
85 return;
86 case MachineOperand::MO_GlobalAddress:
87 // Computing the address of a global symbol, not calling it.
88 O << *getSymbol(MO.getGlobal());
89 printOffset(MO.getOffset(), O);
90 return;
91 }
92 }
93
94 //
95 // isBlockOnlyReachableByFallthrough - We need to override this since the
96 // default AsmPrinter does not print labels for any basic block that
97 // is only reachable by a fall through. That works for all cases except
98 // for the case in which the basic block is reachable by a fall through but
99 // through an indirect from a jump table. In this case, the jump table
100 // will contain a label not defined by AsmPrinter.
101 //
102 bool HexagonAsmPrinter::
isBlockOnlyReachableByFallthrough(const MachineBasicBlock * MBB) const103 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
104 if (MBB->hasAddressTaken()) {
105 return false;
106 }
107 return AsmPrinter::isBlockOnlyReachableByFallthrough(MBB);
108 }
109
110
111 /// PrintAsmOperand - Print out an operand for an inline asm expression.
112 ///
PrintAsmOperand(const MachineInstr * MI,unsigned OpNo,unsigned AsmVariant,const char * ExtraCode,raw_ostream & OS)113 bool HexagonAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
114 unsigned AsmVariant,
115 const char *ExtraCode,
116 raw_ostream &OS) {
117 // Does this asm operand have a single letter operand modifier?
118 if (ExtraCode && ExtraCode[0]) {
119 if (ExtraCode[1] != 0) return true; // Unknown modifier.
120
121 switch (ExtraCode[0]) {
122 default:
123 // See if this is a generic print operand
124 return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, OS);
125 case 'c': // Don't print "$" before a global var name or constant.
126 // Hexagon never has a prefix.
127 printOperand(MI, OpNo, OS);
128 return false;
129 case 'L': // Write second word of DImode reference.
130 // Verify that this operand has two consecutive registers.
131 if (!MI->getOperand(OpNo).isReg() ||
132 OpNo+1 == MI->getNumOperands() ||
133 !MI->getOperand(OpNo+1).isReg())
134 return true;
135 ++OpNo; // Return the high-part.
136 break;
137 case 'I':
138 // Write 'i' if an integer constant, otherwise nothing. Used to print
139 // addi vs add, etc.
140 if (MI->getOperand(OpNo).isImm())
141 OS << "i";
142 return false;
143 }
144 }
145
146 printOperand(MI, OpNo, OS);
147 return false;
148 }
149
PrintAsmMemoryOperand(const MachineInstr * MI,unsigned OpNo,unsigned AsmVariant,const char * ExtraCode,raw_ostream & O)150 bool HexagonAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
151 unsigned OpNo, unsigned AsmVariant,
152 const char *ExtraCode,
153 raw_ostream &O) {
154 if (ExtraCode && ExtraCode[0])
155 return true; // Unknown modifier.
156
157 const MachineOperand &Base = MI->getOperand(OpNo);
158 const MachineOperand &Offset = MI->getOperand(OpNo+1);
159
160 if (Base.isReg())
161 printOperand(MI, OpNo, O);
162 else
163 llvm_unreachable("Unimplemented");
164
165 if (Offset.isImm()) {
166 if (Offset.getImm())
167 O << " + #" << Offset.getImm();
168 }
169 else
170 llvm_unreachable("Unimplemented");
171
172 return false;
173 }
174
175
176 /// printMachineInstruction -- Print out a single Hexagon MI in Darwin syntax to
177 /// the current output stream.
178 ///
EmitInstruction(const MachineInstr * MI)179 void HexagonAsmPrinter::EmitInstruction(const MachineInstr *MI) {
180 if (MI->isBundle()) {
181 std::vector<MachineInstr const *> BundleMIs;
182
183 const MachineBasicBlock *MBB = MI->getParent();
184 MachineBasicBlock::const_instr_iterator MII = MI;
185 ++MII;
186 unsigned int IgnoreCount = 0;
187 while (MII != MBB->end() && MII->isInsideBundle()) {
188 const MachineInstr *MInst = MII;
189 if (MInst->getOpcode() == TargetOpcode::DBG_VALUE ||
190 MInst->getOpcode() == TargetOpcode::IMPLICIT_DEF) {
191 IgnoreCount++;
192 ++MII;
193 continue;
194 }
195 // BundleMIs.push_back(&*MII);
196 BundleMIs.push_back(MInst);
197 ++MII;
198 }
199 unsigned Size = BundleMIs.size();
200 assert((Size + IgnoreCount) == MI->getBundleSize() && "Corrupt Bundle!");
201 for (unsigned Index = 0; Index < Size; Index++) {
202 MCInst MCI;
203
204 HexagonLowerToMC(BundleMIs[Index], MCI, *this);
205 HexagonMCInstrInfo::AppendImplicitOperands(MCI);
206 HexagonMCInstrInfo::setPacketBegin(MCI, Index == 0);
207 HexagonMCInstrInfo::setPacketEnd(MCI, Index == (Size - 1));
208 EmitToStreamer(OutStreamer, MCI);
209 }
210 }
211 else {
212 MCInst MCI;
213 HexagonLowerToMC(MI, MCI, *this);
214 HexagonMCInstrInfo::AppendImplicitOperands(MCI);
215 if (MI->getOpcode() == Hexagon::ENDLOOP0) {
216 HexagonMCInstrInfo::setPacketBegin(MCI, true);
217 HexagonMCInstrInfo::setPacketEnd(MCI, true);
218 }
219 EmitToStreamer(OutStreamer, MCI);
220 }
221
222 return;
223 }
224
LLVMInitializeHexagonAsmPrinter()225 extern "C" void LLVMInitializeHexagonAsmPrinter() {
226 RegisterAsmPrinter<HexagonAsmPrinter> X(TheHexagonTarget);
227 }
228