1 //===----- HexagonMCChecker.cpp - Instruction bundle checking -------------===//
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 implements the checking of insns inside a bundle according to the
10 // packet constraint rules of the Hexagon ISA.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "MCTargetDesc/HexagonMCChecker.h"
15 #include "MCTargetDesc/HexagonBaseInfo.h"
16 #include "MCTargetDesc/HexagonMCInstrInfo.h"
17 #include "MCTargetDesc/HexagonMCShuffler.h"
18 #include "MCTargetDesc/HexagonMCTargetDesc.h"
19
20 #include "llvm/ADT/Twine.h"
21 #include "llvm/MC/MCContext.h"
22 #include "llvm/MC/MCInst.h"
23 #include "llvm/MC/MCInstrDesc.h"
24 #include "llvm/MC/MCRegisterInfo.h"
25 #include "llvm/MC/MCSubtargetInfo.h"
26 #include "llvm/Support/CommandLine.h"
27 #include "llvm/Support/SourceMgr.h"
28 #include <cassert>
29
30 using namespace llvm;
31
32 static cl::opt<bool>
33 RelaxNVChecks("relax-nv-checks", cl::Hidden,
34 cl::desc("Relax checks of new-value validity"));
35
36 const HexagonMCChecker::PredSense
37 HexagonMCChecker::Unconditional(Hexagon::NoRegister, false);
38
init()39 void HexagonMCChecker::init() {
40 // Initialize read-only registers set.
41 ReadOnly.insert(Hexagon::PC);
42 ReadOnly.insert(Hexagon::C9_8);
43
44 // Figure out the loop-registers definitions.
45 if (HexagonMCInstrInfo::isInnerLoop(MCB)) {
46 Defs[Hexagon::SA0].insert(Unconditional); // FIXME: define or change SA0?
47 Defs[Hexagon::LC0].insert(Unconditional);
48 }
49 if (HexagonMCInstrInfo::isOuterLoop(MCB)) {
50 Defs[Hexagon::SA1].insert(Unconditional); // FIXME: define or change SA0?
51 Defs[Hexagon::LC1].insert(Unconditional);
52 }
53
54 if (HexagonMCInstrInfo::isBundle(MCB))
55 // Unfurl a bundle.
56 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCB)) {
57 MCInst const &Inst = *I.getInst();
58 if (HexagonMCInstrInfo::isDuplex(MCII, Inst)) {
59 init(*Inst.getOperand(0).getInst());
60 init(*Inst.getOperand(1).getInst());
61 } else
62 init(Inst);
63 }
64 else
65 init(MCB);
66 }
67
initReg(MCInst const & MCI,unsigned R,unsigned & PredReg,bool & isTrue)68 void HexagonMCChecker::initReg(MCInst const &MCI, unsigned R, unsigned &PredReg,
69 bool &isTrue) {
70 if (HexagonMCInstrInfo::isPredicated(MCII, MCI) &&
71 HexagonMCInstrInfo::isPredReg(RI, R)) {
72 // Note an used predicate register.
73 PredReg = R;
74 isTrue = HexagonMCInstrInfo::isPredicatedTrue(MCII, MCI);
75
76 // Note use of new predicate register.
77 if (HexagonMCInstrInfo::isPredicatedNew(MCII, MCI))
78 NewPreds.insert(PredReg);
79 } else
80 // Note register use. Super-registers are not tracked directly,
81 // but their components.
82 for (MCRegAliasIterator SRI(R, &RI, RI.subregs(R).empty()); SRI.isValid();
83 ++SRI)
84 if (RI.subregs(*SRI).empty())
85 // Skip super-registers used indirectly.
86 Uses.insert(*SRI);
87
88 if (HexagonMCInstrInfo::IsReverseVecRegPair(R))
89 ReversePairs.insert(R);
90 }
91
init(MCInst const & MCI)92 void HexagonMCChecker::init(MCInst const &MCI) {
93 const MCInstrDesc &MCID = HexagonMCInstrInfo::getDesc(MCII, MCI);
94 unsigned PredReg = Hexagon::NoRegister;
95 bool isTrue = false;
96
97 // Get used registers.
98 for (unsigned i = MCID.getNumDefs(); i < MCID.getNumOperands(); ++i)
99 if (MCI.getOperand(i).isReg())
100 initReg(MCI, MCI.getOperand(i).getReg(), PredReg, isTrue);
101 for (MCPhysReg ImpUse : MCID.implicit_uses())
102 initReg(MCI, ImpUse, PredReg, isTrue);
103
104 const bool IgnoreTmpDst = (HexagonMCInstrInfo::hasTmpDst(MCII, MCI) ||
105 HexagonMCInstrInfo::hasHvxTmp(MCII, MCI)) &&
106 STI.hasFeature(Hexagon::ArchV69);
107
108 // Get implicit register definitions.
109 for (MCPhysReg R : MCID.implicit_defs()) {
110 if (Hexagon::R31 != R && MCID.isCall())
111 // Any register other than the LR and the PC are actually volatile ones
112 // as defined by the ABI, not modified implicitly by the call insn.
113 continue;
114 if (Hexagon::PC == R)
115 // Branches are the only insns that can change the PC,
116 // otherwise a read-only register.
117 continue;
118
119 if (Hexagon::USR_OVF == R)
120 // Many insns change the USR implicitly, but only one or another flag.
121 // The instruction table models the USR.OVF flag, which can be
122 // implicitly modified more than once, but cannot be modified in the
123 // same packet with an instruction that modifies is explicitly. Deal
124 // with such situations individually.
125 SoftDefs.insert(R);
126 else if (HexagonMCInstrInfo::isPredReg(RI, R) &&
127 HexagonMCInstrInfo::isPredicateLate(MCII, MCI))
128 // Include implicit late predicates.
129 LatePreds.insert(R);
130 else if (!IgnoreTmpDst)
131 Defs[R].insert(PredSense(PredReg, isTrue));
132 }
133
134 // Figure out explicit register definitions.
135 for (unsigned i = 0; i < MCID.getNumDefs(); ++i) {
136 unsigned R = MCI.getOperand(i).getReg(), S = Hexagon::NoRegister;
137 // USR has subregisters (while C8 does not for technical reasons), so
138 // reset R to USR, since we know how to handle multiple defs of USR,
139 // taking into account its subregisters.
140 if (R == Hexagon::C8)
141 R = Hexagon::USR;
142
143 if (HexagonMCInstrInfo::IsReverseVecRegPair(R))
144 ReversePairs.insert(R);
145
146 // Note register definitions, direct ones as well as indirect side-effects.
147 // Super-registers are not tracked directly, but their components.
148 for (MCRegAliasIterator SRI(R, &RI, RI.subregs(R).empty()); SRI.isValid();
149 ++SRI) {
150 if (!RI.subregs(*SRI).empty())
151 // Skip super-registers defined indirectly.
152 continue;
153
154 if (R == *SRI) {
155 if (S == R)
156 // Avoid scoring the defined register multiple times.
157 continue;
158 else
159 // Note that the defined register has already been scored.
160 S = R;
161 }
162
163 if (Hexagon::P3_0 != R && Hexagon::P3_0 == *SRI)
164 // P3:0 is a special case, since multiple predicate register definitions
165 // in a packet is allowed as the equivalent of their logical "and".
166 // Only an explicit definition of P3:0 is noted as such; if a
167 // side-effect, then note as a soft definition.
168 SoftDefs.insert(*SRI);
169 else if (HexagonMCInstrInfo::isPredicateLate(MCII, MCI) &&
170 HexagonMCInstrInfo::isPredReg(RI, *SRI))
171 // Some insns produce predicates too late to be used in the same packet.
172 LatePreds.insert(*SRI);
173 else if (i == 0 && HexagonMCInstrInfo::getType(MCII, MCI) ==
174 HexagonII::TypeCVI_VM_TMP_LD)
175 // Temporary loads should be used in the same packet, but don't commit
176 // results, so it should be disregarded if another insn changes the same
177 // register.
178 // TODO: relies on the impossibility of a current and a temporary loads
179 // in the same packet.
180 TmpDefs.insert(*SRI);
181 else if (!IgnoreTmpDst)
182 Defs[*SRI].insert(PredSense(PredReg, isTrue));
183 }
184 }
185
186 // Figure out definitions of new predicate registers.
187 if (HexagonMCInstrInfo::isPredicatedNew(MCII, MCI))
188 for (unsigned i = MCID.getNumDefs(); i < MCID.getNumOperands(); ++i)
189 if (MCI.getOperand(i).isReg()) {
190 unsigned P = MCI.getOperand(i).getReg();
191
192 if (HexagonMCInstrInfo::isPredReg(RI, P))
193 NewPreds.insert(P);
194 }
195 }
196
HexagonMCChecker(MCContext & Context,MCInstrInfo const & MCII,MCSubtargetInfo const & STI,MCInst & mcb,MCRegisterInfo const & ri,bool ReportErrors)197 HexagonMCChecker::HexagonMCChecker(MCContext &Context, MCInstrInfo const &MCII,
198 MCSubtargetInfo const &STI, MCInst &mcb,
199 MCRegisterInfo const &ri, bool ReportErrors)
200 : Context(Context), MCB(mcb), RI(ri), MCII(MCII), STI(STI),
201 ReportErrors(ReportErrors) {
202 init();
203 }
204
HexagonMCChecker(HexagonMCChecker const & Other,MCSubtargetInfo const & STI,bool CopyReportErrors)205 HexagonMCChecker::HexagonMCChecker(HexagonMCChecker const &Other,
206 MCSubtargetInfo const &STI,
207 bool CopyReportErrors)
208 : Context(Other.Context), MCB(Other.MCB), RI(Other.RI), MCII(Other.MCII),
209 STI(STI), ReportErrors(CopyReportErrors ? Other.ReportErrors : false) {
210 init();
211 }
212
check(bool FullCheck)213 bool HexagonMCChecker::check(bool FullCheck) {
214 bool chkP = checkPredicates();
215 bool chkNV = checkNewValues();
216 bool chkR = checkRegisters();
217 bool chkRRO = checkRegistersReadOnly();
218 checkRegisterCurDefs();
219 bool chkS = checkSolo();
220 bool chkSh = true;
221 if (FullCheck)
222 chkSh = checkShuffle();
223 bool chkSl = true;
224 if (FullCheck)
225 chkSl = checkSlots();
226 bool chkAXOK = checkAXOK();
227 bool chkCofMax1 = checkCOFMax1();
228 bool chkHWLoop = checkHWLoop();
229 bool chkValidTmpDst = FullCheck ? checkValidTmpDst() : true;
230 bool chkLegalVecRegPair = checkLegalVecRegPair();
231 bool ChkHVXAccum = checkHVXAccum();
232 bool chk = chkP && chkNV && chkR && chkRRO && chkS && chkSh && chkSl &&
233 chkAXOK && chkCofMax1 && chkHWLoop && chkValidTmpDst &&
234 chkLegalVecRegPair && ChkHVXAccum;
235
236 return chk;
237 }
238
isDuplexAGroup(unsigned Opcode)239 static bool isDuplexAGroup(unsigned Opcode) {
240 switch (Opcode) {
241 case Hexagon::SA1_addi:
242 case Hexagon::SA1_addrx:
243 case Hexagon::SA1_addsp:
244 case Hexagon::SA1_and1:
245 case Hexagon::SA1_clrf:
246 case Hexagon::SA1_clrfnew:
247 case Hexagon::SA1_clrt:
248 case Hexagon::SA1_clrtnew:
249 case Hexagon::SA1_cmpeqi:
250 case Hexagon::SA1_combine0i:
251 case Hexagon::SA1_combine1i:
252 case Hexagon::SA1_combine2i:
253 case Hexagon::SA1_combine3i:
254 case Hexagon::SA1_combinerz:
255 case Hexagon::SA1_combinezr:
256 case Hexagon::SA1_dec:
257 case Hexagon::SA1_inc:
258 case Hexagon::SA1_seti:
259 case Hexagon::SA1_setin1:
260 case Hexagon::SA1_sxtb:
261 case Hexagon::SA1_sxth:
262 case Hexagon::SA1_tfr:
263 case Hexagon::SA1_zxtb:
264 case Hexagon::SA1_zxth:
265 return true;
266 break;
267 default:
268 return false;
269 }
270 }
271
isNeitherAnorX(MCInstrInfo const & MCII,MCInst const & ID)272 static bool isNeitherAnorX(MCInstrInfo const &MCII, MCInst const &ID) {
273 if (HexagonMCInstrInfo::isFloat(MCII, ID))
274 return true;
275 unsigned Type = HexagonMCInstrInfo::getType(MCII, ID);
276 switch (Type) {
277 case HexagonII::TypeALU32_2op:
278 case HexagonII::TypeALU32_3op:
279 case HexagonII::TypeALU32_ADDI:
280 case HexagonII::TypeS_2op:
281 case HexagonII::TypeS_3op:
282 case HexagonII::TypeEXTENDER:
283 case HexagonII::TypeM:
284 case HexagonII::TypeALU64:
285 return false;
286 case HexagonII::TypeSUBINSN: {
287 return !isDuplexAGroup(ID.getOpcode());
288 }
289 case HexagonII::TypeDUPLEX:
290 llvm_unreachable("unexpected duplex instruction");
291 default:
292 return true;
293 }
294 }
295
checkAXOK()296 bool HexagonMCChecker::checkAXOK() {
297 MCInst const *HasSoloAXInst = nullptr;
298 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB)) {
299 if (HexagonMCInstrInfo::isSoloAX(MCII, I)) {
300 HasSoloAXInst = &I;
301 }
302 }
303 if (!HasSoloAXInst)
304 return true;
305 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB)) {
306 if (&I != HasSoloAXInst && isNeitherAnorX(MCII, I)) {
307 reportError(
308 HasSoloAXInst->getLoc(),
309 Twine("Instruction can only be in a packet with ALU or non-FPU XTYPE "
310 "instructions"));
311 reportError(I.getLoc(),
312 Twine("Not an ALU or non-FPU XTYPE instruction"));
313 return false;
314 }
315 }
316 return true;
317 }
318
reportBranchErrors()319 void HexagonMCChecker::reportBranchErrors() {
320 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB)) {
321 if (HexagonMCInstrInfo::IsABranchingInst(MCII, STI, I))
322 reportNote(I.getLoc(), "Branching instruction");
323 }
324 }
325
checkHWLoop()326 bool HexagonMCChecker::checkHWLoop() {
327 if (!HexagonMCInstrInfo::isInnerLoop(MCB) &&
328 !HexagonMCInstrInfo::isOuterLoop(MCB))
329 return true;
330 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB)) {
331 if (HexagonMCInstrInfo::IsABranchingInst(MCII, STI, I)) {
332 reportError(MCB.getLoc(),
333 "Branches cannot be in a packet with hardware loops");
334 reportBranchErrors();
335 return false;
336 }
337 }
338 return true;
339 }
340
checkCOFMax1()341 bool HexagonMCChecker::checkCOFMax1() {
342 SmallVector<MCInst const *, 2> BranchLocations;
343 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB)) {
344 if (HexagonMCInstrInfo::IsABranchingInst(MCII, STI, I))
345 BranchLocations.push_back(&I);
346 }
347 for (unsigned J = 0, N = BranchLocations.size(); J < N; ++J) {
348 MCInst const &I = *BranchLocations[J];
349 if (HexagonMCInstrInfo::isCofMax1(MCII, I)) {
350 bool Relax1 = HexagonMCInstrInfo::isCofRelax1(MCII, I);
351 bool Relax2 = HexagonMCInstrInfo::isCofRelax2(MCII, I);
352 if (N > 1 && !Relax1 && !Relax2) {
353 reportError(I.getLoc(),
354 "Instruction may not be in a packet with other branches");
355 reportBranchErrors();
356 return false;
357 }
358 if (N > 1 && J == 0 && !Relax1) {
359 reportError(I.getLoc(),
360 "Instruction may not be the first branch in packet");
361 reportBranchErrors();
362 return false;
363 }
364 if (N > 1 && J == 1 && !Relax2) {
365 reportError(I.getLoc(),
366 "Instruction may not be the second branch in packet");
367 reportBranchErrors();
368 return false;
369 }
370 }
371 }
372 return true;
373 }
374
checkSlots()375 bool HexagonMCChecker::checkSlots() {
376 if (HexagonMCInstrInfo::slotsConsumed(MCII, STI, MCB) >
377 HexagonMCInstrInfo::packetSizeSlots(STI)) {
378 reportError("invalid instruction packet: out of slots");
379 return false;
380 }
381 return true;
382 }
383
384 // Check legal use of predicate registers.
checkPredicates()385 bool HexagonMCChecker::checkPredicates() {
386 // Check for proper use of new predicate registers.
387 for (const auto &I : NewPreds) {
388 unsigned P = I;
389
390 if (!Defs.count(P) || LatePreds.count(P) || Defs.count(Hexagon::P3_0)) {
391 // Error out if the new predicate register is not defined,
392 // or defined "late"
393 // (e.g., "{ if (p3.new)... ; p3 = sp1loop0(#r7:2, Rs) }").
394 reportErrorNewValue(P);
395 return false;
396 }
397 }
398
399 // Check for proper use of auto-anded of predicate registers.
400 for (const auto &I : LatePreds) {
401 unsigned P = I;
402
403 if (LatePreds.count(P) > 1 || Defs.count(P)) {
404 // Error out if predicate register defined "late" multiple times or
405 // defined late and regularly defined
406 // (e.g., "{ p3 = sp1loop0(...); p3 = cmp.eq(...) }".
407 reportErrorRegisters(P);
408 return false;
409 }
410 }
411
412 return true;
413 }
414
415 // Check legal use of new values.
checkNewValues()416 bool HexagonMCChecker::checkNewValues() {
417 for (auto const &ConsumerInst :
418 HexagonMCInstrInfo::bundleInstructions(MCII, MCB)) {
419 if (!HexagonMCInstrInfo::isNewValue(MCII, ConsumerInst))
420 continue;
421
422 const HexagonMCInstrInfo::PredicateInfo ConsumerPredInfo =
423 HexagonMCInstrInfo::predicateInfo(MCII, ConsumerInst);
424
425 bool Branch = HexagonMCInstrInfo::getDesc(MCII, ConsumerInst).isBranch();
426 MCOperand const &Op =
427 HexagonMCInstrInfo::getNewValueOperand(MCII, ConsumerInst);
428 assert(Op.isReg());
429
430 auto Producer = registerProducer(Op.getReg(), ConsumerPredInfo);
431 const MCInst *const ProducerInst = std::get<0>(Producer);
432 const HexagonMCInstrInfo::PredicateInfo ProducerPredInfo =
433 std::get<2>(Producer);
434
435 if (ProducerInst == nullptr) {
436 reportError(ConsumerInst.getLoc(),
437 "New value register consumer has no producer");
438 return false;
439 }
440 if (!RelaxNVChecks) {
441 // Checks that statically prove correct new value consumption
442 if (ProducerPredInfo.isPredicated() &&
443 (!ConsumerPredInfo.isPredicated() ||
444 llvm::HexagonMCInstrInfo::getType(MCII, ConsumerInst) ==
445 HexagonII::TypeNCJ)) {
446 reportNote(
447 ProducerInst->getLoc(),
448 "Register producer is predicated and consumer is unconditional");
449 reportError(ConsumerInst.getLoc(),
450 "Instruction does not have a valid new register producer");
451 return false;
452 }
453 if (ProducerPredInfo.Register != Hexagon::NoRegister &&
454 ProducerPredInfo.Register != ConsumerPredInfo.Register) {
455 reportNote(ProducerInst->getLoc(),
456 "Register producer does not use the same predicate "
457 "register as the consumer");
458 reportError(ConsumerInst.getLoc(),
459 "Instruction does not have a valid new register producer");
460 return false;
461 }
462 }
463 if (ProducerPredInfo.Register == ConsumerPredInfo.Register &&
464 ConsumerPredInfo.PredicatedTrue != ProducerPredInfo.PredicatedTrue) {
465 reportNote(
466 ProducerInst->getLoc(),
467 "Register producer has the opposite predicate sense as consumer");
468 reportError(ConsumerInst.getLoc(),
469 "Instruction does not have a valid new register producer");
470 return false;
471 }
472
473 MCInstrDesc const &Desc = HexagonMCInstrInfo::getDesc(MCII, *ProducerInst);
474 const unsigned ProducerOpIndex = std::get<1>(Producer);
475
476 if (Desc.operands()[ProducerOpIndex].RegClass ==
477 Hexagon::DoubleRegsRegClassID) {
478 reportNote(ProducerInst->getLoc(),
479 "Double registers cannot be new-value producers");
480 reportError(ConsumerInst.getLoc(),
481 "Instruction does not have a valid new register producer");
482 return false;
483 }
484
485 // The ProducerOpIsMemIndex logic checks for the index of the producer
486 // register operand. Z-reg load instructions have an implicit operand
487 // that's not encoded, so the producer won't appear as the 1-th def, it
488 // will be at the 0-th.
489 const unsigned ProducerOpSearchIndex =
490 (HexagonMCInstrInfo::getType(MCII, *ProducerInst) ==
491 HexagonII::TypeCVI_ZW)
492 ? 0
493 : 1;
494
495 const bool ProducerOpIsMemIndex =
496 ((Desc.mayLoad() && ProducerOpIndex == ProducerOpSearchIndex) ||
497 (Desc.mayStore() && ProducerOpIndex == 0));
498
499 if (ProducerOpIsMemIndex) {
500 unsigned Mode = HexagonMCInstrInfo::getAddrMode(MCII, *ProducerInst);
501
502 StringRef ModeError;
503 if (Mode == HexagonII::AbsoluteSet)
504 ModeError = "Absolute-set";
505 if (Mode == HexagonII::PostInc)
506 ModeError = "Auto-increment";
507 if (!ModeError.empty()) {
508 reportNote(ProducerInst->getLoc(),
509 ModeError + " registers cannot be a new-value "
510 "producer");
511 reportError(ConsumerInst.getLoc(),
512 "Instruction does not have a valid new register producer");
513 return false;
514 }
515 }
516 if (Branch && HexagonMCInstrInfo::isFloat(MCII, *ProducerInst)) {
517 reportNote(ProducerInst->getLoc(),
518 "FPU instructions cannot be new-value producers for jumps");
519 reportError(ConsumerInst.getLoc(),
520 "Instruction does not have a valid new register producer");
521 return false;
522 }
523 }
524 return true;
525 }
526
checkRegistersReadOnly()527 bool HexagonMCChecker::checkRegistersReadOnly() {
528 for (auto I : HexagonMCInstrInfo::bundleInstructions(MCB)) {
529 MCInst const &Inst = *I.getInst();
530 unsigned Defs = HexagonMCInstrInfo::getDesc(MCII, Inst).getNumDefs();
531 for (unsigned j = 0; j < Defs; ++j) {
532 MCOperand const &Operand = Inst.getOperand(j);
533 assert(Operand.isReg() && "Def is not a register");
534 unsigned Register = Operand.getReg();
535 if (ReadOnly.find(Register) != ReadOnly.end()) {
536 reportError(Inst.getLoc(), "Cannot write to read-only register `" +
537 Twine(RI.getName(Register)) + "'");
538 return false;
539 }
540 }
541 }
542 return true;
543 }
544
registerUsed(unsigned Register)545 bool HexagonMCChecker::registerUsed(unsigned Register) {
546 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB))
547 for (unsigned j = HexagonMCInstrInfo::getDesc(MCII, I).getNumDefs(),
548 n = I.getNumOperands();
549 j < n; ++j) {
550 MCOperand const &Operand = I.getOperand(j);
551 if (Operand.isReg() && Operand.getReg() == Register)
552 return true;
553 }
554 return false;
555 }
556
557 std::tuple<MCInst const *, unsigned, HexagonMCInstrInfo::PredicateInfo>
registerProducer(unsigned Register,HexagonMCInstrInfo::PredicateInfo ConsumerPredicate)558 HexagonMCChecker::registerProducer(
559 unsigned Register, HexagonMCInstrInfo::PredicateInfo ConsumerPredicate) {
560 std::tuple<MCInst const *, unsigned, HexagonMCInstrInfo::PredicateInfo>
561 WrongSense;
562
563 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB)) {
564 MCInstrDesc const &Desc = HexagonMCInstrInfo::getDesc(MCII, I);
565 auto ProducerPredicate = HexagonMCInstrInfo::predicateInfo(MCII, I);
566
567 for (unsigned J = 0, N = Desc.getNumDefs(); J < N; ++J)
568 for (auto K = MCRegAliasIterator(I.getOperand(J).getReg(), &RI, true);
569 K.isValid(); ++K)
570 if (*K == Register) {
571 if (RelaxNVChecks ||
572 (ProducerPredicate.Register == ConsumerPredicate.Register &&
573 (ProducerPredicate.Register == Hexagon::NoRegister ||
574 ProducerPredicate.PredicatedTrue ==
575 ConsumerPredicate.PredicatedTrue)))
576 return std::make_tuple(&I, J, ProducerPredicate);
577 std::get<0>(WrongSense) = &I;
578 std::get<1>(WrongSense) = J;
579 std::get<2>(WrongSense) = ProducerPredicate;
580 }
581 if (Register == Hexagon::VTMP && HexagonMCInstrInfo::hasTmpDst(MCII, I))
582 return std::make_tuple(&I, 0, HexagonMCInstrInfo::PredicateInfo());
583 }
584 return WrongSense;
585 }
586
checkRegisterCurDefs()587 void HexagonMCChecker::checkRegisterCurDefs() {
588 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB)) {
589 if (HexagonMCInstrInfo::isCVINew(MCII, I) &&
590 HexagonMCInstrInfo::getDesc(MCII, I).mayLoad()) {
591 const unsigned RegDef = I.getOperand(0).getReg();
592
593 bool HasRegDefUse = false;
594 for (MCRegAliasIterator Alias(RegDef, &RI, true); Alias.isValid();
595 ++Alias)
596 HasRegDefUse = HasRegDefUse || registerUsed(*Alias);
597
598 if (!HasRegDefUse)
599 reportWarning("Register `" + Twine(RI.getName(RegDef)) +
600 "' used with `.cur' "
601 "but not used in the same packet");
602 }
603 }
604 }
605
606 // Check for legal register uses and definitions.
checkRegisters()607 bool HexagonMCChecker::checkRegisters() {
608 // Check for proper register definitions.
609 for (const auto &I : Defs) {
610 unsigned R = I.first;
611
612 if (isLoopRegister(R) && Defs.count(R) > 1 &&
613 (HexagonMCInstrInfo::isInnerLoop(MCB) ||
614 HexagonMCInstrInfo::isOuterLoop(MCB))) {
615 // Error out for definitions of loop registers at the end of a loop.
616 reportError("loop-setup and some branch instructions "
617 "cannot be in the same packet");
618 return false;
619 }
620 if (SoftDefs.count(R)) {
621 // Error out for explicit changes to registers also weakly defined
622 // (e.g., "{ usr = r0; r0 = sfadd(...) }").
623 unsigned UsrR = Hexagon::USR; // Silence warning about mixed types in ?:.
624 unsigned BadR = RI.isSubRegister(Hexagon::USR, R) ? UsrR : R;
625 reportErrorRegisters(BadR);
626 return false;
627 }
628 if (!HexagonMCInstrInfo::isPredReg(RI, R) && Defs[R].size() > 1) {
629 // Check for multiple register definitions.
630 PredSet &PM = Defs[R];
631
632 // Check for multiple unconditional register definitions.
633 if (PM.count(Unconditional)) {
634 // Error out on an unconditional change when there are any other
635 // changes, conditional or not.
636 unsigned UsrR = Hexagon::USR;
637 unsigned BadR = RI.isSubRegister(Hexagon::USR, R) ? UsrR : R;
638 reportErrorRegisters(BadR);
639 return false;
640 }
641 // Check for multiple conditional register definitions.
642 for (const auto &J : PM) {
643 PredSense P = J;
644
645 // Check for multiple uses of the same condition.
646 if (PM.count(P) > 1) {
647 // Error out on conditional changes based on the same predicate
648 // (e.g., "{ if (!p0) r0 =...; if (!p0) r0 =... }").
649 reportErrorRegisters(R);
650 return false;
651 }
652 // Check for the use of the complementary condition.
653 P.second = !P.second;
654 if (PM.count(P) && PM.size() > 2) {
655 // Error out on conditional changes based on the same predicate
656 // multiple times
657 // (e.g., "if (p0) r0 =...; if (!p0) r0 =... }; if (!p0) r0 =...").
658 reportErrorRegisters(R);
659 return false;
660 }
661 }
662 }
663 }
664
665 // Check for use of temporary definitions.
666 for (const auto &I : TmpDefs) {
667 unsigned R = I;
668
669 if (!Uses.count(R)) {
670 // special case for vhist
671 bool vHistFound = false;
672 for (auto const &HMI : HexagonMCInstrInfo::bundleInstructions(MCB)) {
673 if (HexagonMCInstrInfo::getType(MCII, *HMI.getInst()) ==
674 HexagonII::TypeCVI_HIST) {
675 vHistFound = true; // vhist() implicitly uses ALL REGxx.tmp
676 break;
677 }
678 }
679 // Warn on an unused temporary definition.
680 if (!vHistFound) {
681 reportWarning("register `" + Twine(RI.getName(R)) +
682 "' used with `.tmp' but not used in the same packet");
683 return true;
684 }
685 }
686 }
687
688 return true;
689 }
690
691 // Check for legal use of solo insns.
checkSolo()692 bool HexagonMCChecker::checkSolo() {
693 if (HexagonMCInstrInfo::bundleSize(MCB) > 1)
694 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB)) {
695 if (HexagonMCInstrInfo::isSolo(MCII, I)) {
696 reportError(I.getLoc(), "Instruction is marked `isSolo' and "
697 "cannot have other instructions in "
698 "the same packet");
699 return false;
700 }
701 }
702
703 return true;
704 }
705
checkShuffle()706 bool HexagonMCChecker::checkShuffle() {
707 HexagonMCShuffler MCSDX(Context, ReportErrors, MCII, STI, MCB);
708 return MCSDX.check();
709 }
710
checkValidTmpDst()711 bool HexagonMCChecker::checkValidTmpDst() {
712 if (!STI.hasFeature(Hexagon::ArchV69)) {
713 return true;
714 }
715 auto HasTmp = [&](MCInst const &I) {
716 return HexagonMCInstrInfo::hasTmpDst(MCII, I) ||
717 HexagonMCInstrInfo::hasHvxTmp(MCII, I);
718 };
719 unsigned HasTmpCount =
720 llvm::count_if(HexagonMCInstrInfo::bundleInstructions(MCII, MCB), HasTmp);
721
722 if (HasTmpCount > 1) {
723 reportError(
724 MCB.getLoc(),
725 "this packet has more than one HVX vtmp/.tmp destination instruction");
726
727 for (auto const &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB))
728 if (HasTmp(I))
729 reportNote(I.getLoc(),
730 "this is an HVX vtmp/.tmp destination instruction");
731
732 return false;
733 }
734 return true;
735 }
736
compoundRegisterMap(unsigned & Register)737 void HexagonMCChecker::compoundRegisterMap(unsigned &Register) {
738 switch (Register) {
739 default:
740 break;
741 case Hexagon::R15:
742 Register = Hexagon::R23;
743 break;
744 case Hexagon::R14:
745 Register = Hexagon::R22;
746 break;
747 case Hexagon::R13:
748 Register = Hexagon::R21;
749 break;
750 case Hexagon::R12:
751 Register = Hexagon::R20;
752 break;
753 case Hexagon::R11:
754 Register = Hexagon::R19;
755 break;
756 case Hexagon::R10:
757 Register = Hexagon::R18;
758 break;
759 case Hexagon::R9:
760 Register = Hexagon::R17;
761 break;
762 case Hexagon::R8:
763 Register = Hexagon::R16;
764 break;
765 }
766 }
767
reportErrorRegisters(unsigned Register)768 void HexagonMCChecker::reportErrorRegisters(unsigned Register) {
769 reportError("register `" + Twine(RI.getName(Register)) +
770 "' modified more than once");
771 }
772
reportErrorNewValue(unsigned Register)773 void HexagonMCChecker::reportErrorNewValue(unsigned Register) {
774 reportError("register `" + Twine(RI.getName(Register)) +
775 "' used with `.new' "
776 "but not validly modified in the same packet");
777 }
778
reportError(Twine const & Msg)779 void HexagonMCChecker::reportError(Twine const &Msg) {
780 reportError(MCB.getLoc(), Msg);
781 }
782
reportError(SMLoc Loc,Twine const & Msg)783 void HexagonMCChecker::reportError(SMLoc Loc, Twine const &Msg) {
784 if (ReportErrors)
785 Context.reportError(Loc, Msg);
786 }
787
reportNote(SMLoc Loc,llvm::Twine const & Msg)788 void HexagonMCChecker::reportNote(SMLoc Loc, llvm::Twine const &Msg) {
789 if (ReportErrors) {
790 auto SM = Context.getSourceManager();
791 if (SM)
792 SM->PrintMessage(Loc, SourceMgr::DK_Note, Msg);
793 }
794 }
795
reportWarning(Twine const & Msg)796 void HexagonMCChecker::reportWarning(Twine const &Msg) {
797 if (ReportErrors)
798 Context.reportWarning(MCB.getLoc(), Msg);
799 }
800
checkLegalVecRegPair()801 bool HexagonMCChecker::checkLegalVecRegPair() {
802 const bool IsPermitted = STI.hasFeature(Hexagon::ArchV67);
803 const bool HasReversePairs = ReversePairs.size() != 0;
804
805 if (!IsPermitted && HasReversePairs) {
806 for (auto R : ReversePairs)
807 reportError("register pair `" + Twine(RI.getName(R)) +
808 "' is not permitted for this architecture");
809 return false;
810 }
811 return true;
812 }
813
814 // Vd.tmp can't be accumulated
checkHVXAccum()815 bool HexagonMCChecker::checkHVXAccum()
816 {
817 for (const auto &I : HexagonMCInstrInfo::bundleInstructions(MCII, MCB)) {
818 bool IsTarget =
819 HexagonMCInstrInfo::isAccumulator(MCII, I) && I.getOperand(0).isReg();
820 if (!IsTarget)
821 continue;
822 unsigned int R = I.getOperand(0).getReg();
823 TmpDefsIterator It = TmpDefs.find(R);
824 if (It != TmpDefs.end()) {
825 reportError("register `" + Twine(RI.getName(R)) + ".tmp" +
826 "' is accumulated in this packet");
827 return false;
828 }
829 }
830 return true;
831 }
832