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 #define DEBUG_TYPE "asm-printer"
17 #include "Hexagon.h"
18 #include "HexagonAsmPrinter.h"
19 #include "HexagonMachineFunctionInfo.h"
20 #include "HexagonMCInst.h"
21 #include "HexagonTargetMachine.h"
22 #include "HexagonSubtarget.h"
23 #include "InstPrinter/HexagonInstPrinter.h"
24 #include "llvm/Constants.h"
25 #include "llvm/DerivedTypes.h"
26 #include "llvm/Module.h"
27 #include "llvm/Analysis/ConstantFolding.h"
28 #include "llvm/Assembly/Writer.h"
29 #include "llvm/CodeGen/AsmPrinter.h"
30 #include "llvm/CodeGen/MachineModuleInfo.h"
31 #include "llvm/CodeGen/MachineFunctionPass.h"
32 #include "llvm/CodeGen/MachineInstr.h"
33 #include "llvm/CodeGen/MachineInstrBuilder.h"
34 #include "llvm/MC/MCAsmInfo.h"
35 #include "llvm/MC/MCContext.h"
36 #include "llvm/MC/MCExpr.h"
37 #include "llvm/MC/MCInst.h"
38 #include "llvm/MC/MCSection.h"
39 #include "llvm/MC/MCStreamer.h"
40 #include "llvm/MC/MCSymbol.h"
41 #include "llvm/Support/MathExtras.h"
42 #include "llvm/Support/CommandLine.h"
43 #include "llvm/Support/Debug.h"
44 #include "llvm/Support/Compiler.h"
45 #include "llvm/Support/Format.h"
46 #include "llvm/Support/raw_ostream.h"
47 #include "llvm/Support/TargetRegistry.h"
48 #include "llvm/Target/Mangler.h"
49 #include "llvm/Target/TargetData.h"
50 #include "llvm/Target/TargetLoweringObjectFile.h"
51 #include "llvm/Target/TargetRegisterInfo.h"
52 #include "llvm/Target/TargetInstrInfo.h"
53 #include "llvm/Target/TargetOptions.h"
54 #include "llvm/ADT/SmallString.h"
55 #include "llvm/ADT/SmallVector.h"
56 #include "llvm/ADT/StringExtras.h"
57
58 using namespace llvm;
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
EmitAlignment(unsigned NumBits,const GlobalValue * GV) const64 void HexagonAsmPrinter::EmitAlignment(unsigned NumBits,
65 const GlobalValue *GV) const {
66 // For basic block level alignment, use ".falign".
67 if (!GV) {
68 OutStreamer.EmitRawText(StringRef("\t.falign"));
69 return;
70 }
71
72 AsmPrinter::EmitAlignment(NumBits, GV);
73 }
74
printOperand(const MachineInstr * MI,unsigned OpNo,raw_ostream & O)75 void HexagonAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
76 raw_ostream &O) {
77 const MachineOperand &MO = MI->getOperand(OpNo);
78
79 switch (MO.getType()) {
80 default: llvm_unreachable ("<unknown operand type>");
81 case MachineOperand::MO_Register:
82 O << HexagonInstPrinter::getRegisterName(MO.getReg());
83 return;
84 case MachineOperand::MO_Immediate:
85 O << MO.getImm();
86 return;
87 case MachineOperand::MO_MachineBasicBlock:
88 O << *MO.getMBB()->getSymbol();
89 return;
90 case MachineOperand::MO_JumpTableIndex:
91 O << *GetJTISymbol(MO.getIndex());
92 // FIXME: PIC relocation model.
93 return;
94 case MachineOperand::MO_ConstantPoolIndex:
95 O << *GetCPISymbol(MO.getIndex());
96 return;
97 case MachineOperand::MO_ExternalSymbol:
98 O << *GetExternalSymbolSymbol(MO.getSymbolName());
99 return;
100 case MachineOperand::MO_GlobalAddress:
101 // Computing the address of a global symbol, not calling it.
102 O << *Mang->getSymbol(MO.getGlobal());
103 printOffset(MO.getOffset(), O);
104 return;
105 }
106 }
107
108 //
109 // isBlockOnlyReachableByFallthrough - We need to override this since the
110 // default AsmPrinter does not print labels for any basic block that
111 // is only reachable by a fall through. That works for all cases except
112 // for the case in which the basic block is reachable by a fall through but
113 // through an indirect from a jump table. In this case, the jump table
114 // will contain a label not defined by AsmPrinter.
115 //
116 bool HexagonAsmPrinter::
isBlockOnlyReachableByFallthrough(const MachineBasicBlock * MBB) const117 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
118 if (MBB->hasAddressTaken()) {
119 return false;
120 }
121 return AsmPrinter::isBlockOnlyReachableByFallthrough(MBB);
122 }
123
124
125 /// PrintAsmOperand - Print out an operand for an inline asm expression.
126 ///
PrintAsmOperand(const MachineInstr * MI,unsigned OpNo,unsigned AsmVariant,const char * ExtraCode,raw_ostream & OS)127 bool HexagonAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
128 unsigned AsmVariant,
129 const char *ExtraCode,
130 raw_ostream &OS) {
131 // Does this asm operand have a single letter operand modifier?
132 if (ExtraCode && ExtraCode[0]) {
133 if (ExtraCode[1] != 0) return true; // Unknown modifier.
134
135 switch (ExtraCode[0]) {
136 default:
137 // See if this is a generic print operand
138 return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, OS);
139 case 'c': // Don't print "$" before a global var name or constant.
140 // Hexagon never has a prefix.
141 printOperand(MI, OpNo, OS);
142 return false;
143 case 'L': // Write second word of DImode reference.
144 // Verify that this operand has two consecutive registers.
145 if (!MI->getOperand(OpNo).isReg() ||
146 OpNo+1 == MI->getNumOperands() ||
147 !MI->getOperand(OpNo+1).isReg())
148 return true;
149 ++OpNo; // Return the high-part.
150 break;
151 case 'I':
152 // Write 'i' if an integer constant, otherwise nothing. Used to print
153 // addi vs add, etc.
154 if (MI->getOperand(OpNo).isImm())
155 OS << "i";
156 return false;
157 }
158 }
159
160 printOperand(MI, OpNo, OS);
161 return false;
162 }
163
PrintAsmMemoryOperand(const MachineInstr * MI,unsigned OpNo,unsigned AsmVariant,const char * ExtraCode,raw_ostream & O)164 bool HexagonAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
165 unsigned OpNo, unsigned AsmVariant,
166 const char *ExtraCode,
167 raw_ostream &O) {
168 if (ExtraCode && ExtraCode[0])
169 return true; // Unknown modifier.
170
171 const MachineOperand &Base = MI->getOperand(OpNo);
172 const MachineOperand &Offset = MI->getOperand(OpNo+1);
173
174 if (Base.isReg())
175 printOperand(MI, OpNo, O);
176 else
177 llvm_unreachable("Unimplemented");
178
179 if (Offset.isImm()) {
180 if (Offset.getImm())
181 O << " + #" << Offset.getImm();
182 }
183 else
184 llvm_unreachable("Unimplemented");
185
186 return false;
187 }
188
printPredicateOperand(const MachineInstr * MI,unsigned OpNo,raw_ostream & O)189 void HexagonAsmPrinter::printPredicateOperand(const MachineInstr *MI,
190 unsigned OpNo,
191 raw_ostream &O) {
192 llvm_unreachable("Unimplemented");
193 }
194
195
196 /// printMachineInstruction -- Print out a single Hexagon MI in Darwin syntax to
197 /// the current output stream.
198 ///
EmitInstruction(const MachineInstr * MI)199 void HexagonAsmPrinter::EmitInstruction(const MachineInstr *MI) {
200 if (MI->isBundle()) {
201 std::vector<const MachineInstr*> BundleMIs;
202
203 const MachineBasicBlock *MBB = MI->getParent();
204 MachineBasicBlock::const_instr_iterator MII = MI;
205 ++MII;
206 unsigned int IgnoreCount = 0;
207 while (MII != MBB->end() && MII->isInsideBundle()) {
208 const MachineInstr *MInst = MII;
209 if (MInst->getOpcode() == TargetOpcode::DBG_VALUE ||
210 MInst->getOpcode() == TargetOpcode::IMPLICIT_DEF) {
211 IgnoreCount++;
212 ++MII;
213 continue;
214 }
215 //BundleMIs.push_back(&*MII);
216 BundleMIs.push_back(MInst);
217 ++MII;
218 }
219 unsigned Size = BundleMIs.size();
220 assert((Size+IgnoreCount) == MI->getBundleSize() && "Corrupt Bundle!");
221 for (unsigned Index = 0; Index < Size; Index++) {
222 HexagonMCInst MCI;
223 MCI.setStartPacket(Index == 0);
224 MCI.setEndPacket(Index == (Size-1));
225
226 HexagonLowerToMC(BundleMIs[Index], MCI, *this);
227 OutStreamer.EmitInstruction(MCI);
228 }
229 }
230 else {
231 HexagonMCInst MCI;
232 if (MI->getOpcode() == Hexagon::ENDLOOP0) {
233 MCI.setStartPacket(true);
234 MCI.setEndPacket(true);
235 }
236 HexagonLowerToMC(MI, MCI, *this);
237 OutStreamer.EmitInstruction(MCI);
238 }
239
240 return;
241 }
242
243 /// PrintUnmangledNameSafely - Print out the printable characters in the name.
244 /// Don't print things like \n or \0.
245 // static void PrintUnmangledNameSafely(const Value *V, raw_ostream &OS) {
246 // for (const char *Name = V->getNameStart(), *E = Name+V->getNameLen();
247 // Name != E; ++Name)
248 // if (isprint(*Name))
249 // OS << *Name;
250 // }
251
252
printAddrModeBasePlusOffset(const MachineInstr * MI,int OpNo,raw_ostream & O)253 void HexagonAsmPrinter::printAddrModeBasePlusOffset(const MachineInstr *MI,
254 int OpNo, raw_ostream &O) {
255 const MachineOperand &MO1 = MI->getOperand(OpNo);
256 const MachineOperand &MO2 = MI->getOperand(OpNo+1);
257
258 O << HexagonInstPrinter::getRegisterName(MO1.getReg())
259 << " + #"
260 << MO2.getImm();
261 }
262
263
printGlobalOperand(const MachineInstr * MI,int OpNo,raw_ostream & O)264 void HexagonAsmPrinter::printGlobalOperand(const MachineInstr *MI, int OpNo,
265 raw_ostream &O) {
266 const MachineOperand &MO = MI->getOperand(OpNo);
267 assert( (MO.getType() == MachineOperand::MO_GlobalAddress) &&
268 "Expecting global address");
269
270 O << *Mang->getSymbol(MO.getGlobal());
271 if (MO.getOffset() != 0) {
272 O << " + ";
273 O << MO.getOffset();
274 }
275 }
276
printJumpTable(const MachineInstr * MI,int OpNo,raw_ostream & O)277 void HexagonAsmPrinter::printJumpTable(const MachineInstr *MI, int OpNo,
278 raw_ostream &O) {
279 const MachineOperand &MO = MI->getOperand(OpNo);
280 assert( (MO.getType() == MachineOperand::MO_JumpTableIndex) &&
281 "Expecting jump table index");
282
283 // Hexagon_TODO: Do we need name mangling?
284 O << *GetJTISymbol(MO.getIndex());
285 }
286
printConstantPool(const MachineInstr * MI,int OpNo,raw_ostream & O)287 void HexagonAsmPrinter::printConstantPool(const MachineInstr *MI, int OpNo,
288 raw_ostream &O) {
289 const MachineOperand &MO = MI->getOperand(OpNo);
290 assert( (MO.getType() == MachineOperand::MO_ConstantPoolIndex) &&
291 "Expecting constant pool index");
292
293 // Hexagon_TODO: Do we need name mangling?
294 O << *GetCPISymbol(MO.getIndex());
295 }
296
createHexagonMCInstPrinter(const Target & T,unsigned SyntaxVariant,const MCAsmInfo & MAI,const MCInstrInfo & MII,const MCRegisterInfo & MRI,const MCSubtargetInfo & STI)297 static MCInstPrinter *createHexagonMCInstPrinter(const Target &T,
298 unsigned SyntaxVariant,
299 const MCAsmInfo &MAI,
300 const MCInstrInfo &MII,
301 const MCRegisterInfo &MRI,
302 const MCSubtargetInfo &STI) {
303 if (SyntaxVariant == 0)
304 return(new HexagonInstPrinter(MAI, MII, MRI));
305 else
306 return NULL;
307 }
308
LLVMInitializeHexagonAsmPrinter()309 extern "C" void LLVMInitializeHexagonAsmPrinter() {
310 RegisterAsmPrinter<HexagonAsmPrinter> X(TheHexagonTarget);
311
312 TargetRegistry::RegisterMCInstPrinter(TheHexagonTarget,
313 createHexagonMCInstPrinter);
314 }
315