xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonMCCodeEmitter.cpp (revision 5956d97f4b3204318ceb6aa9c77bd0bc6ea87a41)
1 //===- HexagonMCCodeEmitter.cpp - Hexagon Target Descriptions -------------===//
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 #include "MCTargetDesc/HexagonMCCodeEmitter.h"
10 #include "MCTargetDesc/HexagonBaseInfo.h"
11 #include "MCTargetDesc/HexagonFixupKinds.h"
12 #include "MCTargetDesc/HexagonMCExpr.h"
13 #include "MCTargetDesc/HexagonMCInstrInfo.h"
14 #include "MCTargetDesc/HexagonMCTargetDesc.h"
15 #include "llvm/ADT/Statistic.h"
16 #include "llvm/MC/MCContext.h"
17 #include "llvm/MC/MCExpr.h"
18 #include "llvm/MC/MCFixup.h"
19 #include "llvm/MC/MCInst.h"
20 #include "llvm/MC/MCInstrDesc.h"
21 #include "llvm/MC/MCInstrInfo.h"
22 #include "llvm/MC/MCRegisterInfo.h"
23 #include "llvm/MC/MCSubtargetInfo.h"
24 #include "llvm/Support/Casting.h"
25 #include "llvm/Support/Compiler.h"
26 #include "llvm/Support/Debug.h"
27 #include "llvm/Support/Endian.h"
28 #include "llvm/Support/EndianStream.h"
29 #include "llvm/Support/ErrorHandling.h"
30 #include "llvm/Support/raw_ostream.h"
31 #include <cassert>
32 #include <cstddef>
33 #include <cstdint>
34 #include <map>
35 #include <string>
36 #include <vector>
37 
38 #define DEBUG_TYPE "mccodeemitter"
39 
40 using namespace llvm;
41 using namespace Hexagon;
42 
43 STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
44 
45 static const unsigned fixup_Invalid = ~0u;
46 
47 #define _ fixup_Invalid
48 #define P(x) Hexagon::fixup_Hexagon##x
49 static const std::map<unsigned, std::vector<unsigned>> ExtFixups = {
50   { MCSymbolRefExpr::VK_DTPREL,
51     { _,                _,              _,                      _,
52       _,                _,              P(_DTPREL_16_X),        P(_DTPREL_11_X),
53       P(_DTPREL_11_X),  P(_9_X),        _,                      P(_DTPREL_11_X),
54       P(_DTPREL_16_X),  _,              _,                      _,
55       P(_DTPREL_16_X),  _,              _,                      _,
56       _,                _,              _,                      _,
57       _,                _,              _,                      _,
58       _,                _,              _,                      _,
59       P(_DTPREL_32_6_X) }},
60   { MCSymbolRefExpr::VK_GOT,
61     { _,                _,              _,                      _,
62       _,                _,              P(_GOT_11_X),           _ /* [1] */,
63       _ /* [1] */,      P(_9_X),        _,                      P(_GOT_11_X),
64       P(_GOT_16_X),     _,              _,                      _,
65       P(_GOT_16_X),     _,              _,                      _,
66       _,                _,              _,                      _,
67       _,                _,              _,                      _,
68       _,                _,              _,                      _,
69       P(_GOT_32_6_X)    }},
70   { MCSymbolRefExpr::VK_GOTREL,
71     { _,                _,              _,                      _,
72       _,                _,              P(_GOTREL_11_X),        P(_GOTREL_11_X),
73       P(_GOTREL_11_X),  P(_9_X),        _,                      P(_GOTREL_11_X),
74       P(_GOTREL_16_X),  _,              _,                      _,
75       P(_GOTREL_16_X),  _,              _,                      _,
76       _,                _,              _,                      _,
77       _,                _,              _,                      _,
78       _,                _,              _,                      _,
79       P(_GOTREL_32_6_X) }},
80   { MCSymbolRefExpr::VK_TPREL,
81     { _,                _,              _,                      _,
82       _,                _,              P(_TPREL_16_X),         P(_TPREL_11_X),
83       P(_TPREL_11_X),   P(_9_X),        _,                      P(_TPREL_11_X),
84       P(_TPREL_16_X),   _,              _,                      _,
85       P(_TPREL_16_X),   _,              _,                      _,
86       _,                _,              _,                      _,
87       _,                _,              _,                      _,
88       _,                _,              _,                      _,
89       P(_TPREL_32_6_X)  }},
90   { MCSymbolRefExpr::VK_Hexagon_GD_GOT,
91     { _,                _,              _,                      _,
92       _,                _,              P(_GD_GOT_16_X),        P(_GD_GOT_11_X),
93       P(_GD_GOT_11_X),  P(_9_X),        _,                      P(_GD_GOT_11_X),
94       P(_GD_GOT_16_X),  _,              _,                      _,
95       P(_GD_GOT_16_X),  _,              _,                      _,
96       _,                _,              _,                      _,
97       _,                _,              _,                      _,
98       _,                _,              _,                      _,
99       P(_GD_GOT_32_6_X) }},
100   { MCSymbolRefExpr::VK_Hexagon_GD_PLT,
101     { _,                _,              _,                      _,
102       _,                _,              _,                      _,
103       _,                P(_9_X),        _,                      P(_GD_PLT_B22_PCREL_X),
104       _,                _,              _,                      _,
105       _,                _,              _,                      _,
106       _,                _,              P(_GD_PLT_B22_PCREL_X), _,
107       _,                _,              _,                      _,
108       _,                _,              _,                      _,
109       _                 }},
110   { MCSymbolRefExpr::VK_Hexagon_IE,
111     { _,                _,              _,                      _,
112       _,                _,              P(_IE_16_X),            _,
113       _,                P(_9_X),        _,                      _,
114       P(_IE_16_X),      _,              _,                      _,
115       P(_IE_16_X),      _,              _,                      _,
116       _,                _,              _,                      _,
117       _,                _,              _,                      _,
118       _,                _,              _,                      _,
119       P(_IE_32_6_X)     }},
120   { MCSymbolRefExpr::VK_Hexagon_IE_GOT,
121     { _,                _,              _,                      _,
122       _,                _,              P(_IE_GOT_11_X),        P(_IE_GOT_11_X),
123       P(_IE_GOT_11_X),  P(_9_X),        _,                      P(_IE_GOT_11_X),
124       P(_IE_GOT_16_X),  _,              _,                      _,
125       P(_IE_GOT_16_X),  _,              _,                      _,
126       _,                _,              _,                      _,
127       _,                _,              _,                      _,
128       _,                _,              _,                      _,
129       P(_IE_GOT_32_6_X) }},
130   { MCSymbolRefExpr::VK_Hexagon_LD_GOT,
131     { _,                _,              _,                      _,
132       _,                _,              P(_LD_GOT_11_X),        P(_LD_GOT_11_X),
133       P(_LD_GOT_11_X),  P(_9_X),        _,                      P(_LD_GOT_11_X),
134       P(_LD_GOT_16_X),  _,              _,                      _,
135       P(_LD_GOT_16_X),  _,              _,                      _,
136       _,                _,              _,                      _,
137       _,                _,              _,                      _,
138       _,                _,              _,                      _,
139       P(_LD_GOT_32_6_X) }},
140   { MCSymbolRefExpr::VK_Hexagon_LD_PLT,
141     { _,                _,              _,                      _,
142       _,                _,              _,                      _,
143       _,                P(_9_X),        _,                      P(_LD_PLT_B22_PCREL_X),
144       _,                _,              _,                      _,
145       _,                _,              _,                      _,
146       _,                _,              P(_LD_PLT_B22_PCREL_X), _,
147       _,                _,              _,                      _,
148       _,                _,              _,                      _,
149       _                 }},
150   { MCSymbolRefExpr::VK_PCREL,
151     { _,                _,              _,                      _,
152       _,                _,              P(_6_PCREL_X),          _,
153       _,                P(_9_X),        _,                      _,
154       _,                _,              _,                      _,
155       _,                _,              _,                      _,
156       _,                _,              _,                      _,
157       _,                _,              _,                      _,
158       _,                _,              _,                      _,
159       P(_32_PCREL)      }},
160   { MCSymbolRefExpr::VK_None,
161     { _,                _,              _,                      _,
162       _,                _,              P(_6_X),                P(_8_X),
163       P(_8_X),          P(_9_X),        P(_10_X),               P(_11_X),
164       P(_12_X),         P(_B13_PCREL),  _,                      P(_B15_PCREL_X),
165       P(_16_X),         _,              _,                      _,
166       _,                _,              P(_B22_PCREL_X),        _,
167       _,                _,              _,                      _,
168       _,                _,              _,                      _,
169       P(_32_6_X)        }},
170 };
171 // [1] The fixup is GOT_16_X for signed values and GOT_11_X for unsigned.
172 
173 static const std::map<unsigned, std::vector<unsigned>> StdFixups = {
174   { MCSymbolRefExpr::VK_DTPREL,
175     { _,                _,              _,                      _,
176       _,                _,              _,                      _,
177       _,                _,              _,                      _,
178       _,                _,              _,                      _,
179       P(_DTPREL_16),    _,              _,                      _,
180       _,                _,              _,                      _,
181       _,                _,              _,                      _,
182       _,                _,              _,                      _,
183       P(_DTPREL_32)     }},
184   { MCSymbolRefExpr::VK_GOT,
185     { _,                _,              _,                      _,
186       _,                _,              _,                      _,
187       _,                _,              _,                      _,
188       _,                _,              _,                      _,
189       _,                _,              _,                      _,
190       _,                _,              _,                      _,
191       _,                _,              _,                      _,
192       _,                _,              _,                      _,
193       P(_GOT_32)        }},
194   { MCSymbolRefExpr::VK_GOTREL,
195     { _,                _,              _,                      _,
196       _,                _,              _,                      _,
197       _,                _,              _,                      _,
198       _,                _,              _,                      _,
199       _ /* [2] */,      _,              _,                      _,
200       _,                _,              _,                      _,
201       _,                _,              _,                      _,
202       _,                _,              _,                      _,
203       P(_GOTREL_32)     }},
204   { MCSymbolRefExpr::VK_PLT,
205     { _,                _,              _,                      _,
206       _,                _,              _,                      _,
207       _,                _,              _,                      _,
208       _,                _,              _,                      _,
209       _,                _,              _,                      _,
210       _,                _,              P(_PLT_B22_PCREL),      _,
211       _,                _,              _,                      _,
212       _,                _,              _,                      _,
213       _                 }},
214   { MCSymbolRefExpr::VK_TPREL,
215     { _,                _,              _,                      _,
216       _,                _,              _,                      _,
217       _,                _,              _,                      P(_TPREL_11_X),
218       _,                _,              _,                      _,
219       P(_TPREL_16),     _,              _,                      _,
220       _,                _,              _,                      _,
221       _,                _,              _,                      _,
222       _,                _,              _,                      _,
223       P(_TPREL_32)      }},
224   { MCSymbolRefExpr::VK_Hexagon_GD_GOT,
225     { _,                _,              _,                      _,
226       _,                _,              _,                      _,
227       _,                _,              _,                      _,
228       _,                _,              _,                      _,
229       P(_GD_GOT_16),    _,              _,                      _,
230       _,                _,              _,                      _,
231       _,                _,              _,                      _,
232       _,                _,              _,                      _,
233       P(_GD_GOT_32)     }},
234   { MCSymbolRefExpr::VK_Hexagon_GD_PLT,
235     { _,                _,              _,                      _,
236       _,                _,              _,                      _,
237       _,                _,              _,                      _,
238       _,                _,              _,                      _,
239       _,                _,              _,                      _,
240       _,                _,              P(_GD_PLT_B22_PCREL),   _,
241       _,                _,              _,                      _,
242       _,                _,              _,                      _,
243       _                 }},
244   { MCSymbolRefExpr::VK_Hexagon_GPREL,
245     { _,                _,              _,                      _,
246       _,                _,              _,                      _,
247       _,                _,              _,                      _,
248       _,                _,              _,                      _,
249       P(_GPREL16_0),    _,              _,                      _,
250       _,                _,              _,                      _,
251       _,                _,              _,                      _,
252       _,                _,              _,                      _,
253       _                 }},
254   { MCSymbolRefExpr::VK_Hexagon_HI16,
255     { _,                _,              _,                      _,
256       _,                _,              _,                      _,
257       _,                _,              _,                      _,
258       _,                _,              _,                      _,
259       P(_HI16),         _,              _,                      _,
260       _,                _,              _,                      _,
261       _,                _,              _,                      _,
262       _,                _,              _,                      _,
263       _                 }},
264   { MCSymbolRefExpr::VK_Hexagon_IE,
265     { _,                _,              _,                      _,
266       _,                _,              _,                      _,
267       _,                _,              _,                      _,
268       _,                _,              _,                      _,
269       _,                _,              _,                      _,
270       _,                _,              _,                      _,
271       _,                _,              _,                      _,
272       _,                _,              _,                      _,
273       P(_IE_32)         }},
274   { MCSymbolRefExpr::VK_Hexagon_IE_GOT,
275     { _,                _,              _,                      _,
276       _,                _,              _,                      _,
277       _,                _,              _,                      _,
278       _,                _,              _,                      _,
279       P(_IE_GOT_16),    _,              _,                      _,
280       _,                _,              _,                      _,
281       _,                _,              _,                      _,
282       _,                _,              _,                      _,
283       P(_IE_GOT_32)     }},
284   { MCSymbolRefExpr::VK_Hexagon_LD_GOT,
285     { _,                _,              _,                      _,
286       _,                _,              _,                      _,
287       _,                _,              _,                      _,
288       _,                _,              _,                      _,
289       P(_LD_GOT_16),    _,              _,                      _,
290       _,                _,              _,                      _,
291       _,                _,              _,                      _,
292       _,                _,              _,                      _,
293       P(_LD_GOT_32)     }},
294   { MCSymbolRefExpr::VK_Hexagon_LD_PLT,
295     { _,                _,              _,                      _,
296       _,                _,              _,                      _,
297       _,                _,              _,                      _,
298       _,                _,              _,                      _,
299       _,                _,              _,                      _,
300       _,                _,              P(_LD_PLT_B22_PCREL),   _,
301       _,                _,              _,                      _,
302       _,                _,              _,                      _,
303       _                 }},
304   { MCSymbolRefExpr::VK_Hexagon_LO16,
305     { _,                _,              _,                      _,
306       _,                _,              _,                      _,
307       _,                _,              _,                      _,
308       _,                _,              _,                      _,
309       P(_LO16),         _,              _,                      _,
310       _,                _,              _,                      _,
311       _,                _,              _,                      _,
312       _,                _,              _,                      _,
313       _                 }},
314   { MCSymbolRefExpr::VK_PCREL,
315     { _,                _,              _,                      _,
316       _,                _,              _,                      _,
317       _,                _,              _,                      _,
318       _,                _,              _,                      _,
319       _,                _,              _,                      _,
320       _,                _,              _,                      _,
321       _,                _,              _,                      _,
322       _,                _,              _,                      _,
323       P(_32_PCREL)      }},
324   { MCSymbolRefExpr::VK_None,
325     { _,                _,              _,                      _,
326       _,                _,              _,                      _,
327       _,                _,              _,                      _,
328       _,                P(_B13_PCREL),  _,                      P(_B15_PCREL),
329       _,                _,              _,                      _,
330       _,                _,              P(_B22_PCREL),          _,
331       _,                _,              _,                      _,
332       _,                _,              _,                      _,
333       P(_32)            }},
334 };
335 //
336 // [2] The actual fixup is LO16 or HI16, depending on the instruction.
337 #undef P
338 #undef _
339 
340 uint32_t HexagonMCCodeEmitter::parseBits(size_t Last, MCInst const &MCB,
341                                          MCInst const &MCI) const {
342   bool Duplex = HexagonMCInstrInfo::isDuplex(MCII, MCI);
343   if (State.Index == 0) {
344     if (HexagonMCInstrInfo::isInnerLoop(MCB)) {
345       assert(!Duplex);
346       assert(State.Index != Last);
347       return HexagonII::INST_PARSE_LOOP_END;
348     }
349   }
350   if (State.Index == 1) {
351     if (HexagonMCInstrInfo::isOuterLoop(MCB)) {
352       assert(!Duplex);
353       assert(State.Index != Last);
354       return HexagonII::INST_PARSE_LOOP_END;
355     }
356   }
357   if (Duplex) {
358     assert(State.Index == Last);
359     return HexagonII::INST_PARSE_DUPLEX;
360   }
361   if (State.Index == Last)
362     return HexagonII::INST_PARSE_PACKET_END;
363   return HexagonII::INST_PARSE_NOT_END;
364 }
365 
366 /// Emit the bundle.
367 void HexagonMCCodeEmitter::encodeInstruction(const MCInst &MI, raw_ostream &OS,
368                                              SmallVectorImpl<MCFixup> &Fixups,
369                                              const MCSubtargetInfo &STI) const {
370   MCInst &HMB = const_cast<MCInst &>(MI);
371 
372   assert(HexagonMCInstrInfo::isBundle(HMB));
373   LLVM_DEBUG(dbgs() << "Encoding bundle\n";);
374   State.Addend = 0;
375   State.Extended = false;
376   State.Bundle = &MI;
377   State.Index = 0;
378   size_t Last = HexagonMCInstrInfo::bundleSize(HMB) - 1;
379   FeatureBitset Features = computeAvailableFeatures(STI.getFeatureBits());
380 
381   for (auto &I : HexagonMCInstrInfo::bundleInstructions(HMB)) {
382     MCInst &HMI = const_cast<MCInst &>(*I.getInst());
383     verifyInstructionPredicates(HMI, Features);
384 
385     EncodeSingleInstruction(HMI, OS, Fixups, STI, parseBits(Last, HMB, HMI));
386     State.Extended = HexagonMCInstrInfo::isImmext(HMI);
387     State.Addend += HEXAGON_INSTR_SIZE;
388     ++State.Index;
389   }
390 }
391 
392 static bool RegisterMatches(unsigned Consumer, unsigned Producer,
393                             unsigned Producer2) {
394   return (Consumer == Producer) || (Consumer == Producer2) ||
395          HexagonMCInstrInfo::IsSingleConsumerRefPairProducer(Producer,
396                                                              Consumer);
397 }
398 
399 /// EncodeSingleInstruction - Emit a single
400 void HexagonMCCodeEmitter::EncodeSingleInstruction(const MCInst &MI,
401       raw_ostream &OS, SmallVectorImpl<MCFixup> &Fixups,
402       const MCSubtargetInfo &STI, uint32_t Parse) const {
403   assert(!HexagonMCInstrInfo::isBundle(MI));
404   uint64_t Binary;
405 
406   // Pseudo instructions don't get encoded and shouldn't be here
407   // in the first place!
408   assert(!HexagonMCInstrInfo::getDesc(MCII, MI).isPseudo() &&
409          "pseudo-instruction found");
410   LLVM_DEBUG(dbgs() << "Encoding insn `"
411                     << HexagonMCInstrInfo::getName(MCII, MI) << "'\n");
412 
413   Binary = getBinaryCodeForInstr(MI, Fixups, STI);
414   unsigned Opc = MI.getOpcode();
415 
416   // Check for unimplemented instructions. Immediate extenders
417   // are encoded as zero, so they need to be accounted for.
418   if (!Binary && Opc != DuplexIClass0 && Opc != A4_ext) {
419     LLVM_DEBUG(dbgs() << "Unimplemented inst `"
420                       << HexagonMCInstrInfo::getName(MCII, MI) << "'\n");
421     llvm_unreachable("Unimplemented Instruction");
422   }
423   Binary |= Parse;
424 
425   // if we need to emit a duplexed instruction
426   if (Opc >= Hexagon::DuplexIClass0 && Opc <= Hexagon::DuplexIClassF) {
427     assert(Parse == HexagonII::INST_PARSE_DUPLEX &&
428            "Emitting duplex without duplex parse bits");
429     unsigned DupIClass = MI.getOpcode() - Hexagon::DuplexIClass0;
430     // 29 is the bit position.
431     // 0b1110 =0xE bits are masked off and down shifted by 1 bit.
432     // Last bit is moved to bit position 13
433     Binary = ((DupIClass & 0xE) << (29 - 1)) | ((DupIClass & 0x1) << 13);
434 
435     const MCInst *Sub0 = MI.getOperand(0).getInst();
436     const MCInst *Sub1 = MI.getOperand(1).getInst();
437 
438     // Get subinstruction slot 0.
439     unsigned SubBits0 = getBinaryCodeForInstr(*Sub0, Fixups, STI);
440     // Get subinstruction slot 1.
441     State.SubInst1 = true;
442     unsigned SubBits1 = getBinaryCodeForInstr(*Sub1, Fixups, STI);
443     State.SubInst1 = false;
444 
445     Binary |= SubBits0 | (SubBits1 << 16);
446   }
447   support::endian::write<uint32_t>(OS, Binary, support::little);
448   ++MCNumEmitted;
449 }
450 
451 [[noreturn]] static void raise_relocation_error(unsigned Width, unsigned Kind) {
452   std::string Text;
453   raw_string_ostream Stream(Text);
454   Stream << "Unrecognized relocation combination: width=" << Width
455          << " kind=" << Kind;
456   report_fatal_error(Twine(Stream.str()));
457 }
458 
459 /// Some insns are not extended and thus have no bits. These cases require
460 /// a more brute force method for determining the correct relocation.
461 Hexagon::Fixups HexagonMCCodeEmitter::getFixupNoBits(
462       MCInstrInfo const &MCII, const MCInst &MI, const MCOperand &MO,
463       const MCSymbolRefExpr::VariantKind VarKind) const {
464   const MCInstrDesc &MCID = HexagonMCInstrInfo::getDesc(MCII, MI);
465   unsigned InsnType = HexagonMCInstrInfo::getType(MCII, MI);
466   using namespace Hexagon;
467 
468   if (InsnType == HexagonII::TypeEXTENDER) {
469     if (VarKind == MCSymbolRefExpr::VK_None) {
470       auto Instrs = HexagonMCInstrInfo::bundleInstructions(*State.Bundle);
471       for (auto I = Instrs.begin(), N = Instrs.end(); I != N; ++I) {
472         if (I->getInst() != &MI)
473           continue;
474         assert(I+1 != N && "Extender cannot be last in packet");
475         const MCInst &NextI = *(I+1)->getInst();
476         const MCInstrDesc &NextD = HexagonMCInstrInfo::getDesc(MCII, NextI);
477         if (NextD.isBranch() || NextD.isCall() ||
478             HexagonMCInstrInfo::getType(MCII, NextI) == HexagonII::TypeCR)
479           return fixup_Hexagon_B32_PCREL_X;
480         return fixup_Hexagon_32_6_X;
481       }
482     }
483 
484     static const std::map<unsigned,unsigned> Relocs = {
485       { MCSymbolRefExpr::VK_GOTREL,         fixup_Hexagon_GOTREL_32_6_X },
486       { MCSymbolRefExpr::VK_GOT,            fixup_Hexagon_GOT_32_6_X },
487       { MCSymbolRefExpr::VK_TPREL,          fixup_Hexagon_TPREL_32_6_X },
488       { MCSymbolRefExpr::VK_DTPREL,         fixup_Hexagon_DTPREL_32_6_X },
489       { MCSymbolRefExpr::VK_Hexagon_GD_GOT, fixup_Hexagon_GD_GOT_32_6_X },
490       { MCSymbolRefExpr::VK_Hexagon_LD_GOT, fixup_Hexagon_LD_GOT_32_6_X },
491       { MCSymbolRefExpr::VK_Hexagon_IE,     fixup_Hexagon_IE_32_6_X },
492       { MCSymbolRefExpr::VK_Hexagon_IE_GOT, fixup_Hexagon_IE_GOT_32_6_X },
493       { MCSymbolRefExpr::VK_PCREL,          fixup_Hexagon_B32_PCREL_X },
494       { MCSymbolRefExpr::VK_Hexagon_GD_PLT, fixup_Hexagon_GD_PLT_B32_PCREL_X },
495       { MCSymbolRefExpr::VK_Hexagon_LD_PLT, fixup_Hexagon_LD_PLT_B32_PCREL_X },
496     };
497 
498     auto F = Relocs.find(VarKind);
499     if (F != Relocs.end())
500       return Hexagon::Fixups(F->second);
501     raise_relocation_error(0, VarKind);
502   }
503 
504   if (MCID.isBranch())
505     return fixup_Hexagon_B13_PCREL;
506 
507   static const std::map<unsigned,unsigned> RelocsLo = {
508     { MCSymbolRefExpr::VK_GOT,            fixup_Hexagon_GOT_LO16 },
509     { MCSymbolRefExpr::VK_GOTREL,         fixup_Hexagon_GOTREL_LO16 },
510     { MCSymbolRefExpr::VK_Hexagon_GD_GOT, fixup_Hexagon_GD_GOT_LO16 },
511     { MCSymbolRefExpr::VK_Hexagon_LD_GOT, fixup_Hexagon_LD_GOT_LO16 },
512     { MCSymbolRefExpr::VK_Hexagon_IE,     fixup_Hexagon_IE_LO16 },
513     { MCSymbolRefExpr::VK_Hexagon_IE_GOT, fixup_Hexagon_IE_GOT_LO16 },
514     { MCSymbolRefExpr::VK_TPREL,          fixup_Hexagon_TPREL_LO16 },
515     { MCSymbolRefExpr::VK_DTPREL,         fixup_Hexagon_DTPREL_LO16 },
516     { MCSymbolRefExpr::VK_None,           fixup_Hexagon_LO16 },
517   };
518 
519   static const std::map<unsigned,unsigned> RelocsHi = {
520     { MCSymbolRefExpr::VK_GOT,            fixup_Hexagon_GOT_HI16 },
521     { MCSymbolRefExpr::VK_GOTREL,         fixup_Hexagon_GOTREL_HI16 },
522     { MCSymbolRefExpr::VK_Hexagon_GD_GOT, fixup_Hexagon_GD_GOT_HI16 },
523     { MCSymbolRefExpr::VK_Hexagon_LD_GOT, fixup_Hexagon_LD_GOT_HI16 },
524     { MCSymbolRefExpr::VK_Hexagon_IE,     fixup_Hexagon_IE_HI16 },
525     { MCSymbolRefExpr::VK_Hexagon_IE_GOT, fixup_Hexagon_IE_GOT_HI16 },
526     { MCSymbolRefExpr::VK_TPREL,          fixup_Hexagon_TPREL_HI16 },
527     { MCSymbolRefExpr::VK_DTPREL,         fixup_Hexagon_DTPREL_HI16 },
528     { MCSymbolRefExpr::VK_None,           fixup_Hexagon_HI16 },
529   };
530 
531   switch (MCID.getOpcode()) {
532     case Hexagon::LO:
533     case Hexagon::A2_tfril: {
534       auto F = RelocsLo.find(VarKind);
535       if (F != RelocsLo.end())
536         return Hexagon::Fixups(F->second);
537       break;
538     }
539     case Hexagon::HI:
540     case Hexagon::A2_tfrih: {
541       auto F = RelocsHi.find(VarKind);
542       if (F != RelocsHi.end())
543         return Hexagon::Fixups(F->second);
544       break;
545     }
546   }
547 
548   raise_relocation_error(0, VarKind);
549 }
550 
551 static bool isPCRel(unsigned Kind) {
552   switch (Kind){
553   case fixup_Hexagon_B22_PCREL:
554   case fixup_Hexagon_B15_PCREL:
555   case fixup_Hexagon_B7_PCREL:
556   case fixup_Hexagon_B13_PCREL:
557   case fixup_Hexagon_B9_PCREL:
558   case fixup_Hexagon_B32_PCREL_X:
559   case fixup_Hexagon_B22_PCREL_X:
560   case fixup_Hexagon_B15_PCREL_X:
561   case fixup_Hexagon_B13_PCREL_X:
562   case fixup_Hexagon_B9_PCREL_X:
563   case fixup_Hexagon_B7_PCREL_X:
564   case fixup_Hexagon_32_PCREL:
565   case fixup_Hexagon_PLT_B22_PCREL:
566   case fixup_Hexagon_GD_PLT_B22_PCREL:
567   case fixup_Hexagon_LD_PLT_B22_PCREL:
568   case fixup_Hexagon_GD_PLT_B22_PCREL_X:
569   case fixup_Hexagon_LD_PLT_B22_PCREL_X:
570   case fixup_Hexagon_6_PCREL_X:
571     return true;
572   default:
573     return false;
574   }
575 }
576 
577 unsigned HexagonMCCodeEmitter::getExprOpValue(const MCInst &MI,
578       const MCOperand &MO, const MCExpr *ME, SmallVectorImpl<MCFixup> &Fixups,
579       const MCSubtargetInfo &STI) const {
580   if (isa<HexagonMCExpr>(ME))
581     ME = &HexagonMCInstrInfo::getExpr(*ME);
582   int64_t Value;
583   if (ME->evaluateAsAbsolute(Value)) {
584     bool InstExtendable = HexagonMCInstrInfo::isExtendable(MCII, MI) ||
585                           HexagonMCInstrInfo::isExtended(MCII, MI);
586     // Only sub-instruction #1 can be extended in a duplex. If MI is a
587     // sub-instruction #0, it is not extended even if Extended is true
588     // (it can be true for the duplex as a whole).
589     bool IsSub0 = HexagonMCInstrInfo::isSubInstruction(MI) && !State.SubInst1;
590     if (State.Extended && InstExtendable && !IsSub0) {
591       unsigned OpIdx = ~0u;
592       for (unsigned I = 0, E = MI.getNumOperands(); I != E; ++I) {
593         if (&MO != &MI.getOperand(I))
594           continue;
595         OpIdx = I;
596         break;
597       }
598       assert(OpIdx != ~0u);
599       if (OpIdx == HexagonMCInstrInfo::getExtendableOp(MCII, MI)) {
600         unsigned Shift = HexagonMCInstrInfo::getExtentAlignment(MCII, MI);
601         Value = (Value & 0x3f) << Shift;
602       }
603     }
604     return Value;
605   }
606   assert(ME->getKind() == MCExpr::SymbolRef ||
607          ME->getKind() == MCExpr::Binary);
608   if (ME->getKind() == MCExpr::Binary) {
609     MCBinaryExpr const *Binary = cast<MCBinaryExpr>(ME);
610     getExprOpValue(MI, MO, Binary->getLHS(), Fixups, STI);
611     getExprOpValue(MI, MO, Binary->getRHS(), Fixups, STI);
612     return 0;
613   }
614 
615   unsigned FixupKind = fixup_Invalid;
616   const MCSymbolRefExpr *MCSRE = static_cast<const MCSymbolRefExpr *>(ME);
617   const MCInstrDesc &MCID = HexagonMCInstrInfo::getDesc(MCII, MI);
618   unsigned FixupWidth = HexagonMCInstrInfo::getExtentBits(MCII, MI) -
619                         HexagonMCInstrInfo::getExtentAlignment(MCII, MI);
620   MCSymbolRefExpr::VariantKind VarKind = MCSRE->getKind();
621   unsigned Opc = MCID.getOpcode();
622   unsigned IType = HexagonMCInstrInfo::getType(MCII, MI);
623 
624   LLVM_DEBUG(dbgs() << "----------------------------------------\n"
625                     << "Opcode Name: " << HexagonMCInstrInfo::getName(MCII, MI)
626                     << "\nOpcode: " << Opc << "\nRelocation bits: "
627                     << FixupWidth << "\nAddend: " << State.Addend
628                     << "\nVariant: " << unsigned(VarKind)
629                     << "\n----------------------------------------\n");
630 
631   // Pick the applicable fixup kind for the symbol.
632   // Handle special cases first, the rest will be looked up in the tables.
633 
634   if (FixupWidth == 16 && !State.Extended) {
635     if (VarKind == MCSymbolRefExpr::VK_None) {
636       if (HexagonMCInstrInfo::s27_2_reloc(*MO.getExpr())) {
637         // A2_iconst.
638         FixupKind = Hexagon::fixup_Hexagon_27_REG;
639       } else {
640         // Look for GP-relative fixups.
641         unsigned Shift = HexagonMCInstrInfo::getExtentAlignment(MCII, MI);
642         static const Hexagon::Fixups GPRelFixups[] = {
643           Hexagon::fixup_Hexagon_GPREL16_0, Hexagon::fixup_Hexagon_GPREL16_1,
644           Hexagon::fixup_Hexagon_GPREL16_2, Hexagon::fixup_Hexagon_GPREL16_3
645         };
646         assert(Shift < array_lengthof(GPRelFixups));
647         auto UsesGP = [] (const MCInstrDesc &D) {
648           for (const MCPhysReg *U = D.getImplicitUses(); U && *U; ++U)
649             if (*U == Hexagon::GP)
650               return true;
651           return false;
652         };
653         if (UsesGP(MCID))
654           FixupKind = GPRelFixups[Shift];
655       }
656     } else if (VarKind == MCSymbolRefExpr::VK_GOTREL) {
657       // Select between LO/HI.
658       if (Opc == Hexagon::LO)
659         FixupKind = Hexagon::fixup_Hexagon_GOTREL_LO16;
660       else if (Opc == Hexagon::HI)
661         FixupKind = Hexagon::fixup_Hexagon_GOTREL_HI16;
662     }
663   } else {
664     bool BranchOrCR = MCID.isBranch() || IType == HexagonII::TypeCR;
665     switch (FixupWidth) {
666       case 9:
667         if (BranchOrCR)
668           FixupKind = State.Extended ? Hexagon::fixup_Hexagon_B9_PCREL_X
669                                      : Hexagon::fixup_Hexagon_B9_PCREL;
670         break;
671       case 8:
672       case 7:
673         if (State.Extended && VarKind == MCSymbolRefExpr::VK_GOT)
674           FixupKind = HexagonMCInstrInfo::isExtentSigned(MCII, MI)
675                         ? Hexagon::fixup_Hexagon_GOT_16_X
676                         : Hexagon::fixup_Hexagon_GOT_11_X;
677         else if (FixupWidth == 7 && BranchOrCR)
678           FixupKind = State.Extended ? Hexagon::fixup_Hexagon_B7_PCREL_X
679                                      : Hexagon::fixup_Hexagon_B7_PCREL;
680         break;
681       case 0:
682         FixupKind = getFixupNoBits(MCII, MI, MO, VarKind);
683         break;
684     }
685   }
686 
687   if (FixupKind == fixup_Invalid) {
688     const auto &FixupTable = State.Extended ? ExtFixups : StdFixups;
689 
690     auto FindVK = FixupTable.find(VarKind);
691     if (FindVK != FixupTable.end())
692       FixupKind = FindVK->second[FixupWidth];
693   }
694 
695   if (FixupKind == fixup_Invalid)
696     raise_relocation_error(FixupWidth, VarKind);
697 
698   const MCExpr *FixupExpr = MO.getExpr();
699   if (State.Addend != 0 && isPCRel(FixupKind)) {
700     const MCExpr *C = MCConstantExpr::create(State.Addend, MCT);
701     FixupExpr = MCBinaryExpr::createAdd(FixupExpr, C, MCT);
702   }
703 
704   MCFixup Fixup = MCFixup::create(State.Addend, FixupExpr,
705                                   MCFixupKind(FixupKind), MI.getLoc());
706   Fixups.push_back(Fixup);
707   // All of the information is in the fixup.
708   return 0;
709 }
710 
711 unsigned
712 HexagonMCCodeEmitter::getMachineOpValue(MCInst const &MI, MCOperand const &MO,
713                                         SmallVectorImpl<MCFixup> &Fixups,
714                                         MCSubtargetInfo const &STI) const {
715   size_t OperandNumber = ~0U;
716   for (unsigned i = 0, n = MI.getNumOperands(); i < n; ++i)
717     if (&MI.getOperand(i) == &MO) {
718       OperandNumber = i;
719       break;
720     }
721   assert((OperandNumber != ~0U) && "Operand not found");
722 
723   if (HexagonMCInstrInfo::isNewValue(MCII, MI) &&
724       &MO == &HexagonMCInstrInfo::getNewValueOperand(MCII, MI)) {
725     // Calculate the new value distance to the associated producer
726     unsigned SOffset = 0;
727     unsigned VOffset = 0;
728     unsigned UseReg = MO.getReg();
729     unsigned DefReg1 = Hexagon::NoRegister;
730     unsigned DefReg2 = Hexagon::NoRegister;
731 
732     auto Instrs = HexagonMCInstrInfo::bundleInstructions(*State.Bundle);
733     const MCOperand *I = Instrs.begin() + State.Index - 1;
734 
735     for (;; --I) {
736       assert(I != Instrs.begin() - 1 && "Couldn't find producer");
737       MCInst const &Inst = *I->getInst();
738       if (HexagonMCInstrInfo::isImmext(Inst))
739         continue;
740 
741       DefReg1 = Hexagon::NoRegister;
742       DefReg2 = Hexagon::NoRegister;
743       ++SOffset;
744       if (HexagonMCInstrInfo::isVector(MCII, Inst)) {
745         // Vector instructions don't count scalars.
746         ++VOffset;
747       }
748       if (HexagonMCInstrInfo::hasNewValue(MCII, Inst))
749         DefReg1 = HexagonMCInstrInfo::getNewValueOperand(MCII, Inst).getReg();
750       if (HexagonMCInstrInfo::hasNewValue2(MCII, Inst))
751         DefReg2 = HexagonMCInstrInfo::getNewValueOperand2(MCII, Inst).getReg();
752       if (!RegisterMatches(UseReg, DefReg1, DefReg2)) {
753         // This isn't the register we're looking for
754         continue;
755       }
756       if (!HexagonMCInstrInfo::isPredicated(MCII, Inst)) {
757         // Producer is unpredicated
758         break;
759       }
760       assert(HexagonMCInstrInfo::isPredicated(MCII, MI) &&
761              "Unpredicated consumer depending on predicated producer");
762       if (HexagonMCInstrInfo::isPredicatedTrue(MCII, Inst) ==
763           HexagonMCInstrInfo::isPredicatedTrue(MCII, MI))
764         // Producer predicate sense matched ours.
765         break;
766     }
767     // Hexagon PRM 10.11 Construct Nt from distance
768     unsigned Offset = HexagonMCInstrInfo::isVector(MCII, MI) ? VOffset
769                                                              : SOffset;
770     Offset <<= 1;
771     Offset |= HexagonMCInstrInfo::SubregisterBit(UseReg, DefReg1, DefReg2);
772     return Offset;
773   }
774 
775   assert(!MO.isImm());
776   if (MO.isReg()) {
777     unsigned Reg = MO.getReg();
778     switch (HexagonMCInstrInfo::getDesc(MCII, MI).OpInfo[OperandNumber].RegClass) {
779     case GeneralSubRegsRegClassID:
780     case GeneralDoubleLow8RegsRegClassID:
781       return HexagonMCInstrInfo::getDuplexRegisterNumbering(Reg);
782     default:
783       break;
784     }
785     return MCT.getRegisterInfo()->getEncodingValue(Reg);
786   }
787 
788   return getExprOpValue(MI, MO, MO.getExpr(), Fixups, STI);
789 }
790 
791 MCCodeEmitter *llvm::createHexagonMCCodeEmitter(MCInstrInfo const &MII,
792                                                 MCRegisterInfo const &MRI,
793                                                 MCContext &MCT) {
794   return new HexagonMCCodeEmitter(MII, MCT);
795 }
796 
797 #define ENABLE_INSTR_PREDICATE_VERIFIER
798 #include "HexagonGenMCCodeEmitter.inc"
799