1 //===- DAGISelMatcher.cpp - Representation of DAG pattern matcher ---------===//
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 "DAGISelMatcher.h"
10 #include "CodeGenDAGPatterns.h"
11 #include "CodeGenInstruction.h"
12 #include "CodeGenRegisters.h"
13 #include "CodeGenTarget.h"
14 #include "llvm/Support/raw_ostream.h"
15 #include "llvm/TableGen/Record.h"
16 using namespace llvm;
17 
18 void Matcher::anchor() { }
19 
20 void Matcher::dump() const {
21   print(errs(), 0);
22 }
23 
24 void Matcher::print(raw_ostream &OS, unsigned indent) const {
25   printImpl(OS, indent);
26   if (Next)
27     return Next->print(OS, indent);
28 }
29 
30 void Matcher::printOne(raw_ostream &OS) const {
31   printImpl(OS, 0);
32 }
33 
34 /// unlinkNode - Unlink the specified node from this chain.  If Other == this,
35 /// we unlink the next pointer and return it.  Otherwise we unlink Other from
36 /// the list and return this.
37 Matcher *Matcher::unlinkNode(Matcher *Other) {
38   if (this == Other)
39     return takeNext();
40 
41   // Scan until we find the predecessor of Other.
42   Matcher *Cur = this;
43   for (; Cur && Cur->getNext() != Other; Cur = Cur->getNext())
44     /*empty*/;
45 
46   if (!Cur) return nullptr;
47   Cur->takeNext();
48   Cur->setNext(Other->takeNext());
49   return this;
50 }
51 
52 /// canMoveBefore - Return true if this matcher is the same as Other, or if
53 /// we can move this matcher past all of the nodes in-between Other and this
54 /// node.  Other must be equal to or before this.
55 bool Matcher::canMoveBefore(const Matcher *Other) const {
56   for (;; Other = Other->getNext()) {
57     assert(Other && "Other didn't come before 'this'?");
58     if (this == Other) return true;
59 
60     // We have to be able to move this node across the Other node.
61     if (!canMoveBeforeNode(Other))
62       return false;
63   }
64 }
65 
66 /// canMoveBeforeNode - Return true if it is safe to move the current matcher
67 /// across the specified one.
68 bool Matcher::canMoveBeforeNode(const Matcher *Other) const {
69   // We can move simple predicates before record nodes.
70   if (isSimplePredicateNode())
71     return Other->isSimplePredicateOrRecordNode();
72 
73   // We can move record nodes across simple predicates.
74   if (isSimplePredicateOrRecordNode())
75     return isSimplePredicateNode();
76 
77   // We can't move record nodes across each other etc.
78   return false;
79 }
80 
81 
82 ScopeMatcher::~ScopeMatcher() {
83   for (Matcher *C : Children)
84     delete C;
85 }
86 
87 SwitchOpcodeMatcher::~SwitchOpcodeMatcher() {
88   for (auto &C : Cases)
89     delete C.second;
90 }
91 
92 SwitchTypeMatcher::~SwitchTypeMatcher() {
93   for (auto &C : Cases)
94     delete C.second;
95 }
96 
97 CheckPredicateMatcher::CheckPredicateMatcher(
98     const TreePredicateFn &pred, const SmallVectorImpl<unsigned> &Ops)
99   : Matcher(CheckPredicate), Pred(pred.getOrigPatFragRecord()),
100     Operands(Ops.begin(), Ops.end()) {}
101 
102 TreePredicateFn CheckPredicateMatcher::getPredicate() const {
103   return TreePredicateFn(Pred);
104 }
105 
106 unsigned CheckPredicateMatcher::getNumOperands() const {
107   return Operands.size();
108 }
109 
110 unsigned CheckPredicateMatcher::getOperandNo(unsigned i) const {
111   assert(i < Operands.size());
112   return Operands[i];
113 }
114 
115 
116 // printImpl methods.
117 
118 void ScopeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
119   OS.indent(indent) << "Scope\n";
120   for (const Matcher *C : Children) {
121     if (!C)
122       OS.indent(indent+1) << "NULL POINTER\n";
123     else
124       C->print(OS, indent+2);
125   }
126 }
127 
128 void RecordMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
129   OS.indent(indent) << "Record\n";
130 }
131 
132 void RecordChildMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
133   OS.indent(indent) << "RecordChild: " << ChildNo << '\n';
134 }
135 
136 void RecordMemRefMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
137   OS.indent(indent) << "RecordMemRef\n";
138 }
139 
140 void CaptureGlueInputMatcher::printImpl(raw_ostream &OS, unsigned indent) const{
141   OS.indent(indent) << "CaptureGlueInput\n";
142 }
143 
144 void MoveChildMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
145   OS.indent(indent) << "MoveChild " << ChildNo << '\n';
146 }
147 
148 void MoveParentMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
149   OS.indent(indent) << "MoveParent\n";
150 }
151 
152 void CheckSameMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
153   OS.indent(indent) << "CheckSame " << MatchNumber << '\n';
154 }
155 
156 void CheckChildSameMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
157   OS.indent(indent) << "CheckChild" << ChildNo << "Same\n";
158 }
159 
160 void CheckPatternPredicateMatcher::
161 printImpl(raw_ostream &OS, unsigned indent) const {
162   OS.indent(indent) << "CheckPatternPredicate " << Predicate << '\n';
163 }
164 
165 void CheckPredicateMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
166   OS.indent(indent) << "CheckPredicate " << getPredicate().getFnName() << '\n';
167 }
168 
169 void CheckOpcodeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
170   OS.indent(indent) << "CheckOpcode " << Opcode.getEnumName() << '\n';
171 }
172 
173 void SwitchOpcodeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
174   OS.indent(indent) << "SwitchOpcode: {\n";
175   for (const auto &C : Cases) {
176     OS.indent(indent) << "case " << C.first->getEnumName() << ":\n";
177     C.second->print(OS, indent+2);
178   }
179   OS.indent(indent) << "}\n";
180 }
181 
182 
183 void CheckTypeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
184   OS.indent(indent) << "CheckType " << getEnumName(Type) << ", ResNo="
185     << ResNo << '\n';
186 }
187 
188 void SwitchTypeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
189   OS.indent(indent) << "SwitchType: {\n";
190   for (const auto &C : Cases) {
191     OS.indent(indent) << "case " << getEnumName(C.first) << ":\n";
192     C.second->print(OS, indent+2);
193   }
194   OS.indent(indent) << "}\n";
195 }
196 
197 void CheckChildTypeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
198   OS.indent(indent) << "CheckChildType " << ChildNo << " "
199     << getEnumName(Type) << '\n';
200 }
201 
202 
203 void CheckIntegerMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
204   OS.indent(indent) << "CheckInteger " << Value << '\n';
205 }
206 
207 void CheckChildIntegerMatcher::printImpl(raw_ostream &OS,
208                                          unsigned indent) const {
209   OS.indent(indent) << "CheckChildInteger " << ChildNo << " " << Value << '\n';
210 }
211 
212 void CheckCondCodeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
213   OS.indent(indent) << "CheckCondCode ISD::" << CondCodeName << '\n';
214 }
215 
216 void CheckChild2CondCodeMatcher::printImpl(raw_ostream &OS,
217                                            unsigned indent) const {
218   OS.indent(indent) << "CheckChild2CondCode ISD::" << CondCodeName << '\n';
219 }
220 
221 void CheckValueTypeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
222   OS.indent(indent) << "CheckValueType MVT::" << TypeName << '\n';
223 }
224 
225 void CheckComplexPatMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
226   OS.indent(indent) << "CheckComplexPat " << Pattern.getSelectFunc() << '\n';
227 }
228 
229 void CheckAndImmMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
230   OS.indent(indent) << "CheckAndImm " << Value << '\n';
231 }
232 
233 void CheckOrImmMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
234   OS.indent(indent) << "CheckOrImm " << Value << '\n';
235 }
236 
237 void CheckFoldableChainNodeMatcher::printImpl(raw_ostream &OS,
238                                               unsigned indent) const {
239   OS.indent(indent) << "CheckFoldableChainNode\n";
240 }
241 
242 void CheckImmAllOnesVMatcher::printImpl(raw_ostream &OS,
243                                         unsigned indent) const {
244   OS.indent(indent) << "CheckAllOnesV\n";
245 }
246 
247 void CheckImmAllZerosVMatcher::printImpl(raw_ostream &OS,
248                                          unsigned indent) const {
249   OS.indent(indent) << "CheckAllZerosV\n";
250 }
251 
252 void EmitIntegerMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
253   OS.indent(indent) << "EmitInteger " << Val << " VT=" << getEnumName(VT)
254                     << '\n';
255 }
256 
257 void EmitStringIntegerMatcher::
258 printImpl(raw_ostream &OS, unsigned indent) const {
259   OS.indent(indent) << "EmitStringInteger " << Val << " VT=" << getEnumName(VT)
260                     << '\n';
261 }
262 
263 void EmitRegisterMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
264   OS.indent(indent) << "EmitRegister ";
265   if (Reg)
266     OS << Reg->getName();
267   else
268     OS << "zero_reg";
269   OS << " VT=" << getEnumName(VT) << '\n';
270 }
271 
272 void EmitConvertToTargetMatcher::
273 printImpl(raw_ostream &OS, unsigned indent) const {
274   OS.indent(indent) << "EmitConvertToTarget " << Slot << '\n';
275 }
276 
277 void EmitMergeInputChainsMatcher::
278 printImpl(raw_ostream &OS, unsigned indent) const {
279   OS.indent(indent) << "EmitMergeInputChains <todo: args>\n";
280 }
281 
282 void EmitCopyToRegMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
283   OS.indent(indent) << "EmitCopyToReg <todo: args>\n";
284 }
285 
286 void EmitNodeXFormMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
287   OS.indent(indent) << "EmitNodeXForm " << NodeXForm->getName()
288      << " Slot=" << Slot << '\n';
289 }
290 
291 
292 void EmitNodeMatcherCommon::printImpl(raw_ostream &OS, unsigned indent) const {
293   OS.indent(indent);
294   OS << (isa<MorphNodeToMatcher>(this) ? "MorphNodeTo: " : "EmitNode: ")
295      << CGI.Namespace << "::" << CGI.TheDef->getName() << ": <todo flags> ";
296 
297   for (unsigned i = 0, e = VTs.size(); i != e; ++i)
298     OS << ' ' << getEnumName(VTs[i]);
299   OS << '(';
300   for (unsigned i = 0, e = Operands.size(); i != e; ++i)
301     OS << Operands[i] << ' ';
302   OS << ")\n";
303 }
304 
305 void CompleteMatchMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
306   OS.indent(indent) << "CompleteMatch <todo args>\n";
307   OS.indent(indent) << "Src = " << *Pattern.getSrcPattern() << "\n";
308   OS.indent(indent) << "Dst = " << *Pattern.getDstPattern() << "\n";
309 }
310 
311 bool CheckOpcodeMatcher::isEqualImpl(const Matcher *M) const {
312   // Note: pointer equality isn't enough here, we have to check the enum names
313   // to ensure that the nodes are for the same opcode.
314   return cast<CheckOpcodeMatcher>(M)->Opcode.getEnumName() ==
315           Opcode.getEnumName();
316 }
317 
318 bool EmitNodeMatcherCommon::isEqualImpl(const Matcher *m) const {
319   const EmitNodeMatcherCommon *M = cast<EmitNodeMatcherCommon>(m);
320   return &M->CGI == &CGI && M->VTs == VTs && M->Operands == Operands &&
321          M->HasChain == HasChain && M->HasInGlue == HasInGlue &&
322          M->HasOutGlue == HasOutGlue && M->HasMemRefs == HasMemRefs &&
323          M->NumFixedArityOperands == NumFixedArityOperands;
324 }
325 
326 void EmitNodeMatcher::anchor() { }
327 
328 void MorphNodeToMatcher::anchor() { }
329 
330 // isContradictoryImpl Implementations.
331 
332 static bool TypesAreContradictory(MVT::SimpleValueType T1,
333                                   MVT::SimpleValueType T2) {
334   // If the two types are the same, then they are the same, so they don't
335   // contradict.
336   if (T1 == T2) return false;
337 
338   // If either type is about iPtr, then they don't conflict unless the other
339   // one is not a scalar integer type.
340   if (T1 == MVT::iPTR)
341     return !MVT(T2).isInteger() || MVT(T2).isVector();
342 
343   if (T2 == MVT::iPTR)
344     return !MVT(T1).isInteger() || MVT(T1).isVector();
345 
346   // Otherwise, they are two different non-iPTR types, they conflict.
347   return true;
348 }
349 
350 bool CheckOpcodeMatcher::isContradictoryImpl(const Matcher *M) const {
351   if (const CheckOpcodeMatcher *COM = dyn_cast<CheckOpcodeMatcher>(M)) {
352     // One node can't have two different opcodes!
353     // Note: pointer equality isn't enough here, we have to check the enum names
354     // to ensure that the nodes are for the same opcode.
355     return COM->getOpcode().getEnumName() != getOpcode().getEnumName();
356   }
357 
358   // If the node has a known type, and if the type we're checking for is
359   // different, then we know they contradict.  For example, a check for
360   // ISD::STORE will never be true at the same time a check for Type i32 is.
361   if (const CheckTypeMatcher *CT = dyn_cast<CheckTypeMatcher>(M)) {
362     // If checking for a result the opcode doesn't have, it can't match.
363     if (CT->getResNo() >= getOpcode().getNumResults())
364       return true;
365 
366     MVT::SimpleValueType NodeType = getOpcode().getKnownType(CT->getResNo());
367     if (NodeType != MVT::Other)
368       return TypesAreContradictory(NodeType, CT->getType());
369   }
370 
371   return false;
372 }
373 
374 bool CheckTypeMatcher::isContradictoryImpl(const Matcher *M) const {
375   if (const CheckTypeMatcher *CT = dyn_cast<CheckTypeMatcher>(M))
376     return TypesAreContradictory(getType(), CT->getType());
377   return false;
378 }
379 
380 bool CheckChildTypeMatcher::isContradictoryImpl(const Matcher *M) const {
381   if (const CheckChildTypeMatcher *CC = dyn_cast<CheckChildTypeMatcher>(M)) {
382     // If the two checks are about different nodes, we don't know if they
383     // conflict!
384     if (CC->getChildNo() != getChildNo())
385       return false;
386 
387     return TypesAreContradictory(getType(), CC->getType());
388   }
389   return false;
390 }
391 
392 bool CheckIntegerMatcher::isContradictoryImpl(const Matcher *M) const {
393   if (const CheckIntegerMatcher *CIM = dyn_cast<CheckIntegerMatcher>(M))
394     return CIM->getValue() != getValue();
395   return false;
396 }
397 
398 bool CheckChildIntegerMatcher::isContradictoryImpl(const Matcher *M) const {
399   if (const CheckChildIntegerMatcher *CCIM = dyn_cast<CheckChildIntegerMatcher>(M)) {
400     // If the two checks are about different nodes, we don't know if they
401     // conflict!
402     if (CCIM->getChildNo() != getChildNo())
403       return false;
404 
405     return CCIM->getValue() != getValue();
406   }
407   return false;
408 }
409 
410 bool CheckValueTypeMatcher::isContradictoryImpl(const Matcher *M) const {
411   if (const CheckValueTypeMatcher *CVT = dyn_cast<CheckValueTypeMatcher>(M))
412     return CVT->getTypeName() != getTypeName();
413   return false;
414 }
415 
416 bool CheckImmAllOnesVMatcher::isContradictoryImpl(const Matcher *M) const {
417   // AllZeros is contradictory.
418   return isa<CheckImmAllZerosVMatcher>(M);
419 }
420 
421 bool CheckImmAllZerosVMatcher::isContradictoryImpl(const Matcher *M) const {
422   // AllOnes is contradictory.
423   return isa<CheckImmAllOnesVMatcher>(M);
424 }
425 
426 bool CheckCondCodeMatcher::isContradictoryImpl(const Matcher *M) const {
427   if (const auto *CCCM = dyn_cast<CheckCondCodeMatcher>(M))
428     return CCCM->getCondCodeName() != getCondCodeName();
429   return false;
430 }
431 
432 bool CheckChild2CondCodeMatcher::isContradictoryImpl(const Matcher *M) const {
433   if (const auto *CCCCM = dyn_cast<CheckChild2CondCodeMatcher>(M))
434     return CCCCM->getCondCodeName() != getCondCodeName();
435   return false;
436 }
437