xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Hexagon/HexagonAsmPrinter.cpp (revision 59c8e88e72633afbc47a4ace0d2170d00d51f7dc) 
1 //===- HexagonAsmPrinter.cpp - Print machine instrs to Hexagon assembly ---===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file contains a printer that converts from our internal representation
10 // of machine-dependent LLVM code to Hexagon assembly language. This printer is
11 // the output mechanism used by `llc'.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "HexagonAsmPrinter.h"
16 #include "Hexagon.h"
17 #include "HexagonInstrInfo.h"
18 #include "HexagonRegisterInfo.h"
19 #include "HexagonSubtarget.h"
20 #include "MCTargetDesc/HexagonInstPrinter.h"
21 #include "MCTargetDesc/HexagonMCExpr.h"
22 #include "MCTargetDesc/HexagonMCInstrInfo.h"
23 #include "MCTargetDesc/HexagonMCTargetDesc.h"
24 #include "TargetInfo/HexagonTargetInfo.h"
25 #include "llvm/ADT/StringExtras.h"
26 #include "llvm/ADT/StringRef.h"
27 #include "llvm/ADT/Twine.h"
28 #include "llvm/BinaryFormat/ELF.h"
29 #include "llvm/CodeGen/AsmPrinter.h"
30 #include "llvm/CodeGen/MachineBasicBlock.h"
31 #include "llvm/CodeGen/MachineFunction.h"
32 #include "llvm/CodeGen/MachineInstr.h"
33 #include "llvm/CodeGen/MachineOperand.h"
34 #include "llvm/CodeGen/TargetRegisterInfo.h"
35 #include "llvm/CodeGen/TargetSubtargetInfo.h"
36 #include "llvm/MC/MCContext.h"
37 #include "llvm/MC/MCDirectives.h"
38 #include "llvm/MC/MCExpr.h"
39 #include "llvm/MC/MCInst.h"
40 #include "llvm/MC/MCRegisterInfo.h"
41 #include "llvm/MC/MCSectionELF.h"
42 #include "llvm/MC/MCStreamer.h"
43 #include "llvm/MC/MCSymbol.h"
44 #include "llvm/MC/TargetRegistry.h"
45 #include "llvm/Support/Casting.h"
46 #include "llvm/Support/CommandLine.h"
47 #include "llvm/Support/ErrorHandling.h"
48 #include "llvm/Support/raw_ostream.h"
49 #include <algorithm>
50 #include <cassert>
51 #include <cstdint>
52 #include <string>
53 
54 using namespace llvm;
55 
56 namespace llvm {
57 
58 void HexagonLowerToMC(const MCInstrInfo &MCII, const MachineInstr *MI,
59                       MCInst &MCB, HexagonAsmPrinter &AP);
60 
61 } // end namespace llvm
62 
63 #define DEBUG_TYPE "asm-printer"
64 
65 // Given a scalar register return its pair.
66 inline static unsigned getHexagonRegisterPair(unsigned Reg,
67       const MCRegisterInfo *RI) {
68   assert(Hexagon::IntRegsRegClass.contains(Reg));
69   unsigned Pair = *RI->superregs(Reg).begin();
70   assert(Hexagon::DoubleRegsRegClass.contains(Pair));
71   return Pair;
72 }
73 
74 void HexagonAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
75                                      raw_ostream &O) {
76   const MachineOperand &MO = MI->getOperand(OpNo);
77 
78   switch (MO.getType()) {
79   default:
80     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     MO.getMBB()->getSymbol()->print(O, MAI);
89     return;
90   case MachineOperand::MO_ConstantPoolIndex:
91     GetCPISymbol(MO.getIndex())->print(O, MAI);
92     return;
93   case MachineOperand::MO_GlobalAddress:
94     PrintSymbolOperand(MO, O);
95     return;
96   }
97 }
98 
99 // isBlockOnlyReachableByFallthrough - We need to override this since the
100 // default AsmPrinter does not print labels for any basic block that
101 // is only reachable by a fall through. That works for all cases except
102 // for the case in which the basic block is reachable by a fall through but
103 // through an indirect from a jump table. In this case, the jump table
104 // will contain a label not defined by AsmPrinter.
105 bool HexagonAsmPrinter::isBlockOnlyReachableByFallthrough(
106       const MachineBasicBlock *MBB) const {
107   if (MBB->hasAddressTaken())
108     return false;
109   return AsmPrinter::isBlockOnlyReachableByFallthrough(MBB);
110 }
111 
112 /// PrintAsmOperand - Print out an operand for an inline asm expression.
113 bool HexagonAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
114                                         const char *ExtraCode,
115                                         raw_ostream &OS) {
116   // Does this asm operand have a single letter operand modifier?
117   if (ExtraCode && ExtraCode[0]) {
118     if (ExtraCode[1] != 0)
119       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, ExtraCode, OS);
125     case 'L':
126     case 'H': { // The highest-numbered register of a pair.
127       const MachineOperand &MO = MI->getOperand(OpNo);
128       const MachineFunction &MF = *MI->getParent()->getParent();
129       const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
130       if (!MO.isReg())
131         return true;
132       Register RegNumber = MO.getReg();
133       // This should be an assert in the frontend.
134       if (Hexagon::DoubleRegsRegClass.contains(RegNumber))
135         RegNumber = TRI->getSubReg(RegNumber, ExtraCode[0] == 'L' ?
136                                               Hexagon::isub_lo :
137                                               Hexagon::isub_hi);
138       OS << HexagonInstPrinter::getRegisterName(RegNumber);
139       return false;
140     }
141     case 'I':
142       // Write 'i' if an integer constant, otherwise nothing.  Used to print
143       // addi vs add, etc.
144       if (MI->getOperand(OpNo).isImm())
145         OS << "i";
146       return false;
147     }
148   }
149 
150   printOperand(MI, OpNo, OS);
151   return false;
152 }
153 
154 bool HexagonAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
155                                               unsigned OpNo,
156                                               const char *ExtraCode,
157                                               raw_ostream &O) {
158   if (ExtraCode && ExtraCode[0])
159     return true; // Unknown modifier.
160 
161   const MachineOperand &Base  = MI->getOperand(OpNo);
162   const MachineOperand &Offset = MI->getOperand(OpNo+1);
163 
164   if (Base.isReg())
165     printOperand(MI, OpNo, O);
166   else
167     llvm_unreachable("Unimplemented");
168 
169   if (Offset.isImm()) {
170     if (Offset.getImm())
171       O << "+#" << Offset.getImm();
172   } else {
173     llvm_unreachable("Unimplemented");
174   }
175 
176   return false;
177 }
178 
179 static MCSymbol *smallData(AsmPrinter &AP, const MachineInstr &MI,
180                            MCStreamer &OutStreamer, const MCOperand &Imm,
181                            int AlignSize, const MCSubtargetInfo& STI) {
182   MCSymbol *Sym;
183   int64_t Value;
184   if (Imm.getExpr()->evaluateAsAbsolute(Value)) {
185     StringRef sectionPrefix;
186     std::string ImmString;
187     StringRef Name;
188     if (AlignSize == 8) {
189        Name = ".CONST_0000000000000000";
190        sectionPrefix = ".gnu.linkonce.l8";
191        ImmString = utohexstr(Value);
192     } else {
193        Name = ".CONST_00000000";
194        sectionPrefix = ".gnu.linkonce.l4";
195        ImmString = utohexstr(static_cast<uint32_t>(Value));
196     }
197 
198     std::string symbolName =   // Yes, leading zeros are kept.
199       Name.drop_back(ImmString.size()).str() + ImmString;
200     std::string sectionName = sectionPrefix.str() + symbolName;
201 
202     MCSectionELF *Section = OutStreamer.getContext().getELFSection(
203         sectionName, ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
204     OutStreamer.switchSection(Section);
205 
206     Sym = AP.OutContext.getOrCreateSymbol(Twine(symbolName));
207     if (Sym->isUndefined()) {
208       OutStreamer.emitLabel(Sym);
209       OutStreamer.emitSymbolAttribute(Sym, MCSA_Global);
210       OutStreamer.emitIntValue(Value, AlignSize);
211       OutStreamer.emitCodeAlignment(Align(AlignSize), &STI);
212     }
213   } else {
214     assert(Imm.isExpr() && "Expected expression and found none");
215     const MachineOperand &MO = MI.getOperand(1);
216     assert(MO.isGlobal() || MO.isCPI() || MO.isJTI());
217     MCSymbol *MOSymbol = nullptr;
218     if (MO.isGlobal())
219       MOSymbol = AP.getSymbol(MO.getGlobal());
220     else if (MO.isCPI())
221       MOSymbol = AP.GetCPISymbol(MO.getIndex());
222     else if (MO.isJTI())
223       MOSymbol = AP.GetJTISymbol(MO.getIndex());
224     else
225       llvm_unreachable("Unknown operand type!");
226 
227     StringRef SymbolName = MOSymbol->getName();
228     std::string LitaName = ".CONST_" + SymbolName.str();
229 
230     MCSectionELF *Section = OutStreamer.getContext().getELFSection(
231         ".lita", ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC);
232 
233     OutStreamer.switchSection(Section);
234     Sym = AP.OutContext.getOrCreateSymbol(Twine(LitaName));
235     if (Sym->isUndefined()) {
236       OutStreamer.emitLabel(Sym);
237       OutStreamer.emitSymbolAttribute(Sym, MCSA_Local);
238       OutStreamer.emitValue(Imm.getExpr(), AlignSize);
239       OutStreamer.emitCodeAlignment(Align(AlignSize), &STI);
240     }
241   }
242   return Sym;
243 }
244 
245 static MCInst ScaleVectorOffset(MCInst &Inst, unsigned OpNo,
246                                 unsigned VectorSize, MCContext &Ctx) {
247   MCInst T;
248   T.setOpcode(Inst.getOpcode());
249   for (unsigned i = 0, n = Inst.getNumOperands(); i != n; ++i) {
250     if (i != OpNo) {
251       T.addOperand(Inst.getOperand(i));
252       continue;
253     }
254     MCOperand &ImmOp = Inst.getOperand(i);
255     const auto *HE = static_cast<const HexagonMCExpr*>(ImmOp.getExpr());
256     int32_t V = cast<MCConstantExpr>(HE->getExpr())->getValue();
257     auto *NewCE = MCConstantExpr::create(V / int32_t(VectorSize), Ctx);
258     auto *NewHE = HexagonMCExpr::create(NewCE, Ctx);
259     T.addOperand(MCOperand::createExpr(NewHE));
260   }
261   return T;
262 }
263 
264 void HexagonAsmPrinter::HexagonProcessInstruction(MCInst &Inst,
265                                                   const MachineInstr &MI) {
266   MCInst &MappedInst = static_cast <MCInst &>(Inst);
267   const MCRegisterInfo *RI = OutStreamer->getContext().getRegisterInfo();
268   const MachineFunction &MF = *MI.getParent()->getParent();
269   auto &HRI = *MF.getSubtarget<HexagonSubtarget>().getRegisterInfo();
270   unsigned VectorSize = HRI.getRegSizeInBits(Hexagon::HvxVRRegClass) / 8;
271 
272   switch (Inst.getOpcode()) {
273   default:
274     return;
275 
276   case Hexagon::A2_iconst: {
277     Inst.setOpcode(Hexagon::A2_addi);
278     MCOperand Reg = Inst.getOperand(0);
279     MCOperand S16 = Inst.getOperand(1);
280     HexagonMCInstrInfo::setMustNotExtend(*S16.getExpr());
281     HexagonMCInstrInfo::setS27_2_reloc(*S16.getExpr());
282     Inst.clear();
283     Inst.addOperand(Reg);
284     Inst.addOperand(MCOperand::createReg(Hexagon::R0));
285     Inst.addOperand(S16);
286     break;
287   }
288 
289   case Hexagon::A2_tfrf: {
290     const MCConstantExpr *Zero = MCConstantExpr::create(0, OutContext);
291     Inst.setOpcode(Hexagon::A2_paddif);
292     Inst.addOperand(MCOperand::createExpr(Zero));
293     break;
294   }
295 
296   case Hexagon::A2_tfrt: {
297     const MCConstantExpr *Zero = MCConstantExpr::create(0, OutContext);
298     Inst.setOpcode(Hexagon::A2_paddit);
299     Inst.addOperand(MCOperand::createExpr(Zero));
300     break;
301   }
302 
303   case Hexagon::A2_tfrfnew: {
304     const MCConstantExpr *Zero = MCConstantExpr::create(0, OutContext);
305     Inst.setOpcode(Hexagon::A2_paddifnew);
306     Inst.addOperand(MCOperand::createExpr(Zero));
307     break;
308   }
309 
310   case Hexagon::A2_tfrtnew: {
311     const MCConstantExpr *Zero = MCConstantExpr::create(0, OutContext);
312     Inst.setOpcode(Hexagon::A2_padditnew);
313     Inst.addOperand(MCOperand::createExpr(Zero));
314     break;
315   }
316 
317   case Hexagon::A2_zxtb: {
318     const MCConstantExpr *C255 = MCConstantExpr::create(255, OutContext);
319     Inst.setOpcode(Hexagon::A2_andir);
320     Inst.addOperand(MCOperand::createExpr(C255));
321     break;
322   }
323 
324   // "$dst = CONST64(#$src1)",
325   case Hexagon::CONST64:
326     if (!OutStreamer->hasRawTextSupport()) {
327       const MCOperand &Imm = MappedInst.getOperand(1);
328       MCSectionSubPair Current = OutStreamer->getCurrentSection();
329 
330       MCSymbol *Sym =
331           smallData(*this, MI, *OutStreamer, Imm, 8, getSubtargetInfo());
332 
333       OutStreamer->switchSection(Current.first, Current.second);
334       MCInst TmpInst;
335       MCOperand &Reg = MappedInst.getOperand(0);
336       TmpInst.setOpcode(Hexagon::L2_loadrdgp);
337       TmpInst.addOperand(Reg);
338       TmpInst.addOperand(MCOperand::createExpr(
339                          MCSymbolRefExpr::create(Sym, OutContext)));
340       MappedInst = TmpInst;
341 
342     }
343     break;
344   case Hexagon::CONST32:
345     if (!OutStreamer->hasRawTextSupport()) {
346       MCOperand &Imm = MappedInst.getOperand(1);
347       MCSectionSubPair Current = OutStreamer->getCurrentSection();
348       MCSymbol *Sym =
349           smallData(*this, MI, *OutStreamer, Imm, 4, getSubtargetInfo());
350       OutStreamer->switchSection(Current.first, Current.second);
351       MCInst TmpInst;
352       MCOperand &Reg = MappedInst.getOperand(0);
353       TmpInst.setOpcode(Hexagon::L2_loadrigp);
354       TmpInst.addOperand(Reg);
355       TmpInst.addOperand(MCOperand::createExpr(HexagonMCExpr::create(
356           MCSymbolRefExpr::create(Sym, OutContext), OutContext)));
357       MappedInst = TmpInst;
358     }
359     break;
360 
361   // C2_pxfer_map maps to C2_or instruction. Though, it's possible to use
362   // C2_or during instruction selection itself but it results
363   // into suboptimal code.
364   case Hexagon::C2_pxfer_map: {
365     MCOperand &Ps = Inst.getOperand(1);
366     MappedInst.setOpcode(Hexagon::C2_or);
367     MappedInst.addOperand(Ps);
368     return;
369   }
370 
371   // Vector reduce complex multiply by scalar, Rt & 1 map to :hi else :lo
372   // The insn is mapped from the 4 operand to the 3 operand raw form taking
373   // 3 register pairs.
374   case Hexagon::M2_vrcmpys_acc_s1: {
375     MCOperand &Rt = Inst.getOperand(3);
376     assert(Rt.isReg() && "Expected register and none was found");
377     unsigned Reg = RI->getEncodingValue(Rt.getReg());
378     if (Reg & 1)
379       MappedInst.setOpcode(Hexagon::M2_vrcmpys_acc_s1_h);
380     else
381       MappedInst.setOpcode(Hexagon::M2_vrcmpys_acc_s1_l);
382     Rt.setReg(getHexagonRegisterPair(Rt.getReg(), RI));
383     return;
384   }
385   case Hexagon::M2_vrcmpys_s1: {
386     MCOperand &Rt = Inst.getOperand(2);
387     assert(Rt.isReg() && "Expected register and none was found");
388     unsigned Reg = RI->getEncodingValue(Rt.getReg());
389     if (Reg & 1)
390       MappedInst.setOpcode(Hexagon::M2_vrcmpys_s1_h);
391     else
392       MappedInst.setOpcode(Hexagon::M2_vrcmpys_s1_l);
393     Rt.setReg(getHexagonRegisterPair(Rt.getReg(), RI));
394     return;
395   }
396 
397   case Hexagon::M2_vrcmpys_s1rp: {
398     MCOperand &Rt = Inst.getOperand(2);
399     assert(Rt.isReg() && "Expected register and none was found");
400     unsigned Reg = RI->getEncodingValue(Rt.getReg());
401     if (Reg & 1)
402       MappedInst.setOpcode(Hexagon::M2_vrcmpys_s1rp_h);
403     else
404       MappedInst.setOpcode(Hexagon::M2_vrcmpys_s1rp_l);
405     Rt.setReg(getHexagonRegisterPair(Rt.getReg(), RI));
406     return;
407   }
408 
409   case Hexagon::A4_boundscheck: {
410     MCOperand &Rs = Inst.getOperand(1);
411     assert(Rs.isReg() && "Expected register and none was found");
412     unsigned Reg = RI->getEncodingValue(Rs.getReg());
413     if (Reg & 1) // Odd mapped to raw:hi, regpair is rodd:odd-1, like r3:2
414       MappedInst.setOpcode(Hexagon::A4_boundscheck_hi);
415     else         // raw:lo
416       MappedInst.setOpcode(Hexagon::A4_boundscheck_lo);
417     Rs.setReg(getHexagonRegisterPair(Rs.getReg(), RI));
418     return;
419   }
420 
421   case Hexagon::PS_call_nr:
422     Inst.setOpcode(Hexagon::J2_call);
423     break;
424 
425   case Hexagon::S5_asrhub_rnd_sat_goodsyntax: {
426     MCOperand &MO = MappedInst.getOperand(2);
427     int64_t Imm;
428     MCExpr const *Expr = MO.getExpr();
429     bool Success = Expr->evaluateAsAbsolute(Imm);
430     assert(Success && "Expected immediate and none was found");
431     (void)Success;
432     MCInst TmpInst;
433     if (Imm == 0) {
434       TmpInst.setOpcode(Hexagon::S2_vsathub);
435       TmpInst.addOperand(MappedInst.getOperand(0));
436       TmpInst.addOperand(MappedInst.getOperand(1));
437       MappedInst = TmpInst;
438       return;
439     }
440     TmpInst.setOpcode(Hexagon::S5_asrhub_rnd_sat);
441     TmpInst.addOperand(MappedInst.getOperand(0));
442     TmpInst.addOperand(MappedInst.getOperand(1));
443     const MCExpr *One = MCConstantExpr::create(1, OutContext);
444     const MCExpr *Sub = MCBinaryExpr::createSub(Expr, One, OutContext);
445     TmpInst.addOperand(
446         MCOperand::createExpr(HexagonMCExpr::create(Sub, OutContext)));
447     MappedInst = TmpInst;
448     return;
449   }
450 
451   case Hexagon::S5_vasrhrnd_goodsyntax:
452   case Hexagon::S2_asr_i_p_rnd_goodsyntax: {
453     MCOperand &MO2 = MappedInst.getOperand(2);
454     MCExpr const *Expr = MO2.getExpr();
455     int64_t Imm;
456     bool Success = Expr->evaluateAsAbsolute(Imm);
457     assert(Success && "Expected immediate and none was found");
458     (void)Success;
459     MCInst TmpInst;
460     if (Imm == 0) {
461       TmpInst.setOpcode(Hexagon::A2_combinew);
462       TmpInst.addOperand(MappedInst.getOperand(0));
463       MCOperand &MO1 = MappedInst.getOperand(1);
464       unsigned High = RI->getSubReg(MO1.getReg(), Hexagon::isub_hi);
465       unsigned Low = RI->getSubReg(MO1.getReg(), Hexagon::isub_lo);
466       // Add a new operand for the second register in the pair.
467       TmpInst.addOperand(MCOperand::createReg(High));
468       TmpInst.addOperand(MCOperand::createReg(Low));
469       MappedInst = TmpInst;
470       return;
471     }
472 
473     if (Inst.getOpcode() == Hexagon::S2_asr_i_p_rnd_goodsyntax)
474       TmpInst.setOpcode(Hexagon::S2_asr_i_p_rnd);
475     else
476       TmpInst.setOpcode(Hexagon::S5_vasrhrnd);
477     TmpInst.addOperand(MappedInst.getOperand(0));
478     TmpInst.addOperand(MappedInst.getOperand(1));
479     const MCExpr *One = MCConstantExpr::create(1, OutContext);
480     const MCExpr *Sub = MCBinaryExpr::createSub(Expr, One, OutContext);
481     TmpInst.addOperand(
482         MCOperand::createExpr(HexagonMCExpr::create(Sub, OutContext)));
483     MappedInst = TmpInst;
484     return;
485   }
486 
487   // if ("#u5==0") Assembler mapped to: "Rd=Rs"; else Rd=asr(Rs,#u5-1):rnd
488   case Hexagon::S2_asr_i_r_rnd_goodsyntax: {
489     MCOperand &MO = Inst.getOperand(2);
490     MCExpr const *Expr = MO.getExpr();
491     int64_t Imm;
492     bool Success = Expr->evaluateAsAbsolute(Imm);
493     assert(Success && "Expected immediate and none was found");
494     (void)Success;
495     MCInst TmpInst;
496     if (Imm == 0) {
497       TmpInst.setOpcode(Hexagon::A2_tfr);
498       TmpInst.addOperand(MappedInst.getOperand(0));
499       TmpInst.addOperand(MappedInst.getOperand(1));
500       MappedInst = TmpInst;
501       return;
502     }
503     TmpInst.setOpcode(Hexagon::S2_asr_i_r_rnd);
504     TmpInst.addOperand(MappedInst.getOperand(0));
505     TmpInst.addOperand(MappedInst.getOperand(1));
506     const MCExpr *One = MCConstantExpr::create(1, OutContext);
507     const MCExpr *Sub = MCBinaryExpr::createSub(Expr, One, OutContext);
508     TmpInst.addOperand(
509         MCOperand::createExpr(HexagonMCExpr::create(Sub, OutContext)));
510     MappedInst = TmpInst;
511     return;
512   }
513 
514   // Translate a "$Rdd = #imm" to "$Rdd = combine(#[-1,0], #imm)"
515   case Hexagon::A2_tfrpi: {
516     MCInst TmpInst;
517     MCOperand &Rdd = MappedInst.getOperand(0);
518     MCOperand &MO = MappedInst.getOperand(1);
519 
520     TmpInst.setOpcode(Hexagon::A2_combineii);
521     TmpInst.addOperand(Rdd);
522     int64_t Imm;
523     bool Success = MO.getExpr()->evaluateAsAbsolute(Imm);
524     if (Success && Imm < 0) {
525       const MCExpr *MOne = MCConstantExpr::create(-1, OutContext);
526       const HexagonMCExpr *E = HexagonMCExpr::create(MOne, OutContext);
527       TmpInst.addOperand(MCOperand::createExpr(E));
528     } else {
529       const MCExpr *Zero = MCConstantExpr::create(0, OutContext);
530       const HexagonMCExpr *E = HexagonMCExpr::create(Zero, OutContext);
531       TmpInst.addOperand(MCOperand::createExpr(E));
532     }
533     TmpInst.addOperand(MO);
534     MappedInst = TmpInst;
535     return;
536   }
537 
538   // Translate a "$Rdd = $Rss" to "$Rdd = combine($Rs, $Rt)"
539   case Hexagon::A2_tfrp: {
540     MCOperand &MO = MappedInst.getOperand(1);
541     unsigned High = RI->getSubReg(MO.getReg(), Hexagon::isub_hi);
542     unsigned Low = RI->getSubReg(MO.getReg(), Hexagon::isub_lo);
543     MO.setReg(High);
544     // Add a new operand for the second register in the pair.
545     MappedInst.addOperand(MCOperand::createReg(Low));
546     MappedInst.setOpcode(Hexagon::A2_combinew);
547     return;
548   }
549 
550   case Hexagon::A2_tfrpt:
551   case Hexagon::A2_tfrpf: {
552     MCOperand &MO = MappedInst.getOperand(2);
553     unsigned High = RI->getSubReg(MO.getReg(), Hexagon::isub_hi);
554     unsigned Low = RI->getSubReg(MO.getReg(), Hexagon::isub_lo);
555     MO.setReg(High);
556     // Add a new operand for the second register in the pair.
557     MappedInst.addOperand(MCOperand::createReg(Low));
558     MappedInst.setOpcode((Inst.getOpcode() == Hexagon::A2_tfrpt)
559                           ? Hexagon::C2_ccombinewt
560                           : Hexagon::C2_ccombinewf);
561     return;
562   }
563 
564   case Hexagon::A2_tfrptnew:
565   case Hexagon::A2_tfrpfnew: {
566     MCOperand &MO = MappedInst.getOperand(2);
567     unsigned High = RI->getSubReg(MO.getReg(), Hexagon::isub_hi);
568     unsigned Low = RI->getSubReg(MO.getReg(), Hexagon::isub_lo);
569     MO.setReg(High);
570     // Add a new operand for the second register in the pair.
571     MappedInst.addOperand(MCOperand::createReg(Low));
572     MappedInst.setOpcode(Inst.getOpcode() == Hexagon::A2_tfrptnew
573                             ? Hexagon::C2_ccombinewnewt
574                             : Hexagon::C2_ccombinewnewf);
575     return;
576   }
577 
578   case Hexagon::M2_mpysmi: {
579     MCOperand &Imm = MappedInst.getOperand(2);
580     MCExpr const *Expr = Imm.getExpr();
581     int64_t Value;
582     bool Success = Expr->evaluateAsAbsolute(Value);
583     assert(Success);
584     (void)Success;
585     if (Value < 0 && Value > -256) {
586       MappedInst.setOpcode(Hexagon::M2_mpysin);
587       Imm.setExpr(HexagonMCExpr::create(
588           MCUnaryExpr::createMinus(Expr, OutContext), OutContext));
589     } else
590       MappedInst.setOpcode(Hexagon::M2_mpysip);
591     return;
592   }
593 
594   case Hexagon::A2_addsp: {
595     MCOperand &Rt = Inst.getOperand(1);
596     assert(Rt.isReg() && "Expected register and none was found");
597     unsigned Reg = RI->getEncodingValue(Rt.getReg());
598     if (Reg & 1)
599       MappedInst.setOpcode(Hexagon::A2_addsph);
600     else
601       MappedInst.setOpcode(Hexagon::A2_addspl);
602     Rt.setReg(getHexagonRegisterPair(Rt.getReg(), RI));
603     return;
604   }
605 
606   case Hexagon::V6_vd0: {
607     MCInst TmpInst;
608     assert(Inst.getOperand(0).isReg() &&
609            "Expected register and none was found");
610 
611     TmpInst.setOpcode(Hexagon::V6_vxor);
612     TmpInst.addOperand(Inst.getOperand(0));
613     TmpInst.addOperand(Inst.getOperand(0));
614     TmpInst.addOperand(Inst.getOperand(0));
615     MappedInst = TmpInst;
616     return;
617   }
618 
619   case Hexagon::V6_vdd0: {
620     MCInst TmpInst;
621     assert (Inst.getOperand(0).isReg() &&
622             "Expected register and none was found");
623 
624     TmpInst.setOpcode(Hexagon::V6_vsubw_dv);
625     TmpInst.addOperand(Inst.getOperand(0));
626     TmpInst.addOperand(Inst.getOperand(0));
627     TmpInst.addOperand(Inst.getOperand(0));
628     MappedInst = TmpInst;
629     return;
630   }
631 
632   case Hexagon::V6_vL32Ub_pi:
633   case Hexagon::V6_vL32b_cur_pi:
634   case Hexagon::V6_vL32b_nt_cur_pi:
635   case Hexagon::V6_vL32b_pi:
636   case Hexagon::V6_vL32b_nt_pi:
637   case Hexagon::V6_vL32b_nt_tmp_pi:
638   case Hexagon::V6_vL32b_tmp_pi:
639     MappedInst = ScaleVectorOffset(Inst, 3, VectorSize, OutContext);
640     return;
641 
642   case Hexagon::V6_vL32Ub_ai:
643   case Hexagon::V6_vL32b_ai:
644   case Hexagon::V6_vL32b_cur_ai:
645   case Hexagon::V6_vL32b_nt_ai:
646   case Hexagon::V6_vL32b_nt_cur_ai:
647   case Hexagon::V6_vL32b_nt_tmp_ai:
648   case Hexagon::V6_vL32b_tmp_ai:
649     MappedInst = ScaleVectorOffset(Inst, 2, VectorSize, OutContext);
650     return;
651 
652   case Hexagon::V6_vS32Ub_pi:
653   case Hexagon::V6_vS32b_new_pi:
654   case Hexagon::V6_vS32b_nt_new_pi:
655   case Hexagon::V6_vS32b_nt_pi:
656   case Hexagon::V6_vS32b_pi:
657     MappedInst = ScaleVectorOffset(Inst, 2, VectorSize, OutContext);
658     return;
659 
660   case Hexagon::V6_vS32Ub_ai:
661   case Hexagon::V6_vS32b_ai:
662   case Hexagon::V6_vS32b_new_ai:
663   case Hexagon::V6_vS32b_nt_ai:
664   case Hexagon::V6_vS32b_nt_new_ai:
665     MappedInst = ScaleVectorOffset(Inst, 1, VectorSize, OutContext);
666     return;
667 
668   case Hexagon::V6_vL32b_cur_npred_pi:
669   case Hexagon::V6_vL32b_cur_pred_pi:
670   case Hexagon::V6_vL32b_npred_pi:
671   case Hexagon::V6_vL32b_nt_cur_npred_pi:
672   case Hexagon::V6_vL32b_nt_cur_pred_pi:
673   case Hexagon::V6_vL32b_nt_npred_pi:
674   case Hexagon::V6_vL32b_nt_pred_pi:
675   case Hexagon::V6_vL32b_nt_tmp_npred_pi:
676   case Hexagon::V6_vL32b_nt_tmp_pred_pi:
677   case Hexagon::V6_vL32b_pred_pi:
678   case Hexagon::V6_vL32b_tmp_npred_pi:
679   case Hexagon::V6_vL32b_tmp_pred_pi:
680     MappedInst = ScaleVectorOffset(Inst, 4, VectorSize, OutContext);
681     return;
682 
683   case Hexagon::V6_vL32b_cur_npred_ai:
684   case Hexagon::V6_vL32b_cur_pred_ai:
685   case Hexagon::V6_vL32b_npred_ai:
686   case Hexagon::V6_vL32b_nt_cur_npred_ai:
687   case Hexagon::V6_vL32b_nt_cur_pred_ai:
688   case Hexagon::V6_vL32b_nt_npred_ai:
689   case Hexagon::V6_vL32b_nt_pred_ai:
690   case Hexagon::V6_vL32b_nt_tmp_npred_ai:
691   case Hexagon::V6_vL32b_nt_tmp_pred_ai:
692   case Hexagon::V6_vL32b_pred_ai:
693   case Hexagon::V6_vL32b_tmp_npred_ai:
694   case Hexagon::V6_vL32b_tmp_pred_ai:
695     MappedInst = ScaleVectorOffset(Inst, 3, VectorSize, OutContext);
696     return;
697 
698   case Hexagon::V6_vS32Ub_npred_pi:
699   case Hexagon::V6_vS32Ub_pred_pi:
700   case Hexagon::V6_vS32b_new_npred_pi:
701   case Hexagon::V6_vS32b_new_pred_pi:
702   case Hexagon::V6_vS32b_npred_pi:
703   case Hexagon::V6_vS32b_nqpred_pi:
704   case Hexagon::V6_vS32b_nt_new_npred_pi:
705   case Hexagon::V6_vS32b_nt_new_pred_pi:
706   case Hexagon::V6_vS32b_nt_npred_pi:
707   case Hexagon::V6_vS32b_nt_nqpred_pi:
708   case Hexagon::V6_vS32b_nt_pred_pi:
709   case Hexagon::V6_vS32b_nt_qpred_pi:
710   case Hexagon::V6_vS32b_pred_pi:
711   case Hexagon::V6_vS32b_qpred_pi:
712     MappedInst = ScaleVectorOffset(Inst, 3, VectorSize, OutContext);
713     return;
714 
715   case Hexagon::V6_vS32Ub_npred_ai:
716   case Hexagon::V6_vS32Ub_pred_ai:
717   case Hexagon::V6_vS32b_new_npred_ai:
718   case Hexagon::V6_vS32b_new_pred_ai:
719   case Hexagon::V6_vS32b_npred_ai:
720   case Hexagon::V6_vS32b_nqpred_ai:
721   case Hexagon::V6_vS32b_nt_new_npred_ai:
722   case Hexagon::V6_vS32b_nt_new_pred_ai:
723   case Hexagon::V6_vS32b_nt_npred_ai:
724   case Hexagon::V6_vS32b_nt_nqpred_ai:
725   case Hexagon::V6_vS32b_nt_pred_ai:
726   case Hexagon::V6_vS32b_nt_qpred_ai:
727   case Hexagon::V6_vS32b_pred_ai:
728   case Hexagon::V6_vS32b_qpred_ai:
729     MappedInst = ScaleVectorOffset(Inst, 2, VectorSize, OutContext);
730     return;
731 
732   // V65+
733   case Hexagon::V6_vS32b_srls_ai:
734     MappedInst = ScaleVectorOffset(Inst, 1, VectorSize, OutContext);
735     return;
736 
737   case Hexagon::V6_vS32b_srls_pi:
738     MappedInst = ScaleVectorOffset(Inst, 2, VectorSize, OutContext);
739     return;
740   }
741 }
742 
743 /// Print out a single Hexagon MI to the current output stream.
744 void HexagonAsmPrinter::emitInstruction(const MachineInstr *MI) {
745   Hexagon_MC::verifyInstructionPredicates(MI->getOpcode(),
746                                           getSubtargetInfo().getFeatureBits());
747 
748   MCInst MCB;
749   MCB.setOpcode(Hexagon::BUNDLE);
750   MCB.addOperand(MCOperand::createImm(0));
751   const MCInstrInfo &MCII = *Subtarget->getInstrInfo();
752 
753   if (MI->isBundle()) {
754     const MachineBasicBlock* MBB = MI->getParent();
755     MachineBasicBlock::const_instr_iterator MII = MI->getIterator();
756 
757     for (++MII; MII != MBB->instr_end() && MII->isInsideBundle(); ++MII)
758       if (!MII->isDebugInstr() && !MII->isImplicitDef())
759         HexagonLowerToMC(MCII, &*MII, MCB, *this);
760   } else {
761     HexagonLowerToMC(MCII, MI, MCB, *this);
762   }
763 
764   const MachineFunction &MF = *MI->getParent()->getParent();
765   const auto &HII = *MF.getSubtarget<HexagonSubtarget>().getInstrInfo();
766   if (MI->isBundle() && HII.getBundleNoShuf(*MI))
767     HexagonMCInstrInfo::setMemReorderDisabled(MCB);
768 
769   MCContext &Ctx = OutStreamer->getContext();
770   bool Ok = HexagonMCInstrInfo::canonicalizePacket(MCII, *Subtarget, Ctx,
771                                                    MCB, nullptr);
772   assert(Ok); (void)Ok;
773   if (HexagonMCInstrInfo::bundleSize(MCB) == 0)
774     return;
775   OutStreamer->emitInstruction(MCB, getSubtargetInfo());
776 }
777 
778 void HexagonAsmPrinter::EmitSled(const MachineInstr &MI, SledKind Kind) {
779   static const int8_t NoopsInSledCount = 4;
780   // We want to emit the following pattern:
781   //
782   // .L_xray_sled_N:
783   // <xray_sled_base>:
784   // { 	jump .Ltmp0 }
785   // {  nop
786   //    nop
787   //    nop
788   //    nop }
789   // .Ltmp0:
790   //
791   // We need the 4 nop words because at runtime, we'd be patching over the
792   // full 5 words with the following pattern:
793   //
794   // <xray_sled_n>:
795   // { 	immext(#...) // upper 26-bits of trampoline
796   //    r6 = ##...   // lower  6-bits of trampoline
797   //    immext(#...) // upper 26-bits of func id
798   //    r7 = ##... }  // lower 6 bits of func id
799   // { 	callr r6 }
800   //
801   //
802   auto CurSled = OutContext.createTempSymbol("xray_sled_", true);
803   OutStreamer->emitLabel(CurSled);
804 
805   MCInst *SledJump = new (OutContext) MCInst();
806   SledJump->setOpcode(Hexagon::J2_jump);
807   auto PostSled = OutContext.createTempSymbol();
808   SledJump->addOperand(MCOperand::createExpr(HexagonMCExpr::create(
809       MCSymbolRefExpr::create(PostSled, OutContext), OutContext)));
810 
811   // Emit "jump PostSled" instruction, which jumps over the nop series.
812   MCInst SledJumpPacket;
813   SledJumpPacket.setOpcode(Hexagon::BUNDLE);
814   SledJumpPacket.addOperand(MCOperand::createImm(0));
815   SledJumpPacket.addOperand(MCOperand::createInst(SledJump));
816 
817   EmitToStreamer(*OutStreamer, SledJumpPacket);
818 
819   // FIXME: this will emit individual packets, we should
820   // special-case this and combine them into a single packet.
821   emitNops(NoopsInSledCount);
822 
823   OutStreamer->emitLabel(PostSled);
824   recordSled(CurSled, MI, Kind, 2);
825 }
826 
827 void HexagonAsmPrinter::LowerPATCHABLE_FUNCTION_ENTER(const MachineInstr &MI) {
828   EmitSled(MI, SledKind::FUNCTION_ENTER);
829 }
830 
831 void HexagonAsmPrinter::LowerPATCHABLE_FUNCTION_EXIT(const MachineInstr &MI) {
832   EmitSled(MI, SledKind::FUNCTION_EXIT);
833 }
834 
835 void HexagonAsmPrinter::LowerPATCHABLE_TAIL_CALL(const MachineInstr &MI) {
836   EmitSled(MI, SledKind::TAIL_CALL);
837 }
838 
839 extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeHexagonAsmPrinter() {
840   RegisterAsmPrinter<HexagonAsmPrinter> X(getTheHexagonTarget());
841 }
842