1 //===- DAGISelMatcher.cpp - Representation of DAG pattern matcher ---------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "DAGISelMatcher.h"
11 #include "CodeGenDAGPatterns.h"
12 #include "CodeGenTarget.h"
13 #include "Record.h"
14 #include "llvm/Support/raw_ostream.h"
15 #include "llvm/ADT/StringExtras.h"
16 using namespace llvm;
17 
18 void Matcher::dump() const {
19   print(errs(), 0);
20 }
21 
22 void Matcher::print(raw_ostream &OS, unsigned indent) const {
23   printImpl(OS, indent);
24   if (Next)
25     return Next->print(OS, indent);
26 }
27 
28 void Matcher::printOne(raw_ostream &OS) const {
29   printImpl(OS, 0);
30 }
31 
32 /// unlinkNode - Unlink the specified node from this chain.  If Other == this,
33 /// we unlink the next pointer and return it.  Otherwise we unlink Other from
34 /// the list and return this.
35 Matcher *Matcher::unlinkNode(Matcher *Other) {
36   if (this == Other)
37     return takeNext();
38 
39   // Scan until we find the predecessor of Other.
40   Matcher *Cur = this;
41   for (; Cur && Cur->getNext() != Other; Cur = Cur->getNext())
42     /*empty*/;
43 
44   if (Cur == 0) return 0;
45   Cur->takeNext();
46   Cur->setNext(Other->takeNext());
47   return this;
48 }
49 
50 /// canMoveBefore - Return true if this matcher is the same as Other, or if
51 /// we can move this matcher past all of the nodes in-between Other and this
52 /// node.  Other must be equal to or before this.
53 bool Matcher::canMoveBefore(const Matcher *Other) const {
54   for (;; Other = Other->getNext()) {
55     assert(Other && "Other didn't come before 'this'?");
56     if (this == Other) return true;
57 
58     // We have to be able to move this node across the Other node.
59     if (!canMoveBeforeNode(Other))
60       return false;
61   }
62 }
63 
64 /// canMoveBefore - Return true if it is safe to move the current matcher
65 /// across the specified one.
66 bool Matcher::canMoveBeforeNode(const Matcher *Other) const {
67   // We can move simple predicates before record nodes.
68   if (isSimplePredicateNode())
69     return Other->isSimplePredicateOrRecordNode();
70 
71   // We can move record nodes across simple predicates.
72   if (isSimplePredicateOrRecordNode())
73     return isSimplePredicateNode();
74 
75   // We can't move record nodes across each other etc.
76   return false;
77 }
78 
79 
80 ScopeMatcher::~ScopeMatcher() {
81   for (unsigned i = 0, e = Children.size(); i != e; ++i)
82     delete Children[i];
83 }
84 
85 
86 // printImpl methods.
87 
88 void ScopeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
89   OS.indent(indent) << "Scope\n";
90   for (unsigned i = 0, e = getNumChildren(); i != e; ++i) {
91     if (getChild(i) == 0)
92       OS.indent(indent+1) << "NULL POINTER\n";
93     else
94       getChild(i)->print(OS, indent+2);
95   }
96 }
97 
98 void RecordMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
99   OS.indent(indent) << "Record\n";
100 }
101 
102 void RecordChildMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
103   OS.indent(indent) << "RecordChild: " << ChildNo << '\n';
104 }
105 
106 void RecordMemRefMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
107   OS.indent(indent) << "RecordMemRef\n";
108 }
109 
110 void CaptureFlagInputMatcher::printImpl(raw_ostream &OS, unsigned indent) const{
111   OS.indent(indent) << "CaptureFlagInput\n";
112 }
113 
114 void MoveChildMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
115   OS.indent(indent) << "MoveChild " << ChildNo << '\n';
116 }
117 
118 void MoveParentMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
119   OS.indent(indent) << "MoveParent\n";
120 }
121 
122 void CheckSameMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
123   OS.indent(indent) << "CheckSame " << MatchNumber << '\n';
124 }
125 
126 void CheckPatternPredicateMatcher::
127 printImpl(raw_ostream &OS, unsigned indent) const {
128   OS.indent(indent) << "CheckPatternPredicate " << Predicate << '\n';
129 }
130 
131 void CheckPredicateMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
132   OS.indent(indent) << "CheckPredicate " << PredName << '\n';
133 }
134 
135 void CheckOpcodeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
136   OS.indent(indent) << "CheckOpcode " << Opcode.getEnumName() << '\n';
137 }
138 
139 void SwitchOpcodeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
140   OS.indent(indent) << "SwitchOpcode: {\n";
141   for (unsigned i = 0, e = Cases.size(); i != e; ++i) {
142     OS.indent(indent) << "case " << Cases[i].first->getEnumName() << ":\n";
143     Cases[i].second->print(OS, indent+2);
144   }
145   OS.indent(indent) << "}\n";
146 }
147 
148 
149 void CheckTypeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
150   OS.indent(indent) << "CheckType " << getEnumName(Type) << ", ResNo="
151     << ResNo << '\n';
152 }
153 
154 void SwitchTypeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
155   OS.indent(indent) << "SwitchType: {\n";
156   for (unsigned i = 0, e = Cases.size(); i != e; ++i) {
157     OS.indent(indent) << "case " << getEnumName(Cases[i].first) << ":\n";
158     Cases[i].second->print(OS, indent+2);
159   }
160   OS.indent(indent) << "}\n";
161 }
162 
163 void CheckChildTypeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
164   OS.indent(indent) << "CheckChildType " << ChildNo << " "
165     << getEnumName(Type) << '\n';
166 }
167 
168 
169 void CheckIntegerMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
170   OS.indent(indent) << "CheckInteger " << Value << '\n';
171 }
172 
173 void CheckCondCodeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
174   OS.indent(indent) << "CheckCondCode ISD::" << CondCodeName << '\n';
175 }
176 
177 void CheckValueTypeMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
178   OS.indent(indent) << "CheckValueType MVT::" << TypeName << '\n';
179 }
180 
181 void CheckComplexPatMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
182   OS.indent(indent) << "CheckComplexPat " << Pattern.getSelectFunc() << '\n';
183 }
184 
185 void CheckAndImmMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
186   OS.indent(indent) << "CheckAndImm " << Value << '\n';
187 }
188 
189 void CheckOrImmMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
190   OS.indent(indent) << "CheckOrImm " << Value << '\n';
191 }
192 
193 void CheckFoldableChainNodeMatcher::printImpl(raw_ostream &OS,
194                                               unsigned indent) const {
195   OS.indent(indent) << "CheckFoldableChainNode\n";
196 }
197 
198 void EmitIntegerMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
199   OS.indent(indent) << "EmitInteger " << Val << " VT=" << VT << '\n';
200 }
201 
202 void EmitStringIntegerMatcher::
203 printImpl(raw_ostream &OS, unsigned indent) const {
204   OS.indent(indent) << "EmitStringInteger " << Val << " VT=" << VT << '\n';
205 }
206 
207 void EmitRegisterMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
208   OS.indent(indent) << "EmitRegister ";
209   if (Reg)
210     OS << Reg->getName();
211   else
212     OS << "zero_reg";
213   OS << " VT=" << VT << '\n';
214 }
215 
216 void EmitConvertToTargetMatcher::
217 printImpl(raw_ostream &OS, unsigned indent) const {
218   OS.indent(indent) << "EmitConvertToTarget " << Slot << '\n';
219 }
220 
221 void EmitMergeInputChainsMatcher::
222 printImpl(raw_ostream &OS, unsigned indent) const {
223   OS.indent(indent) << "EmitMergeInputChains <todo: args>\n";
224 }
225 
226 void EmitCopyToRegMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
227   OS.indent(indent) << "EmitCopyToReg <todo: args>\n";
228 }
229 
230 void EmitNodeXFormMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
231   OS.indent(indent) << "EmitNodeXForm " << NodeXForm->getName()
232      << " Slot=" << Slot << '\n';
233 }
234 
235 
236 void EmitNodeMatcherCommon::printImpl(raw_ostream &OS, unsigned indent) const {
237   OS.indent(indent);
238   OS << (isa<MorphNodeToMatcher>(this) ? "MorphNodeTo: " : "EmitNode: ")
239      << OpcodeName << ": <todo flags> ";
240 
241   for (unsigned i = 0, e = VTs.size(); i != e; ++i)
242     OS << ' ' << getEnumName(VTs[i]);
243   OS << '(';
244   for (unsigned i = 0, e = Operands.size(); i != e; ++i)
245     OS << Operands[i] << ' ';
246   OS << ")\n";
247 }
248 
249 void MarkFlagResultsMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
250   OS.indent(indent) << "MarkFlagResults <todo: args>\n";
251 }
252 
253 void CompleteMatchMatcher::printImpl(raw_ostream &OS, unsigned indent) const {
254   OS.indent(indent) << "CompleteMatch <todo args>\n";
255   OS.indent(indent) << "Src = " << *Pattern.getSrcPattern() << "\n";
256   OS.indent(indent) << "Dst = " << *Pattern.getDstPattern() << "\n";
257 }
258 
259 // getHashImpl Implementation.
260 
261 unsigned CheckPatternPredicateMatcher::getHashImpl() const {
262   return HashString(Predicate);
263 }
264 
265 unsigned CheckPredicateMatcher::getHashImpl() const {
266   return HashString(PredName);
267 }
268 
269 unsigned CheckOpcodeMatcher::getHashImpl() const {
270   return HashString(Opcode.getEnumName());
271 }
272 
273 unsigned CheckCondCodeMatcher::getHashImpl() const {
274   return HashString(CondCodeName);
275 }
276 
277 unsigned CheckValueTypeMatcher::getHashImpl() const {
278   return HashString(TypeName);
279 }
280 
281 unsigned EmitStringIntegerMatcher::getHashImpl() const {
282   return HashString(Val) ^ VT;
283 }
284 
285 template<typename It>
286 static unsigned HashUnsigneds(It I, It E) {
287   unsigned Result = 0;
288   for (; I != E; ++I)
289     Result = (Result<<3) ^ *I;
290   return Result;
291 }
292 
293 unsigned EmitMergeInputChainsMatcher::getHashImpl() const {
294   return HashUnsigneds(ChainNodes.begin(), ChainNodes.end());
295 }
296 
297 bool CheckOpcodeMatcher::isEqualImpl(const Matcher *M) const {
298   // Note: pointer equality isn't enough here, we have to check the enum names
299   // to ensure that the nodes are for the same opcode.
300   return cast<CheckOpcodeMatcher>(M)->Opcode.getEnumName() ==
301           Opcode.getEnumName();
302 }
303 
304 
305 bool EmitNodeMatcherCommon::isEqualImpl(const Matcher *m) const {
306   const EmitNodeMatcherCommon *M = cast<EmitNodeMatcherCommon>(m);
307   return M->OpcodeName == OpcodeName && M->VTs == VTs &&
308          M->Operands == Operands && M->HasChain == HasChain &&
309          M->HasInFlag == HasInFlag && M->HasOutFlag == HasOutFlag &&
310          M->HasMemRefs == HasMemRefs &&
311          M->NumFixedArityOperands == NumFixedArityOperands;
312 }
313 
314 unsigned EmitNodeMatcherCommon::getHashImpl() const {
315   return (HashString(OpcodeName) << 4) | Operands.size();
316 }
317 
318 
319 unsigned MarkFlagResultsMatcher::getHashImpl() const {
320   return HashUnsigneds(FlagResultNodes.begin(), FlagResultNodes.end());
321 }
322 
323 unsigned CompleteMatchMatcher::getHashImpl() const {
324   return HashUnsigneds(Results.begin(), Results.end()) ^
325           ((unsigned)(intptr_t)&Pattern << 8);
326 }
327 
328 // isContradictoryImpl Implementations.
329 
330 static bool TypesAreContradictory(MVT::SimpleValueType T1,
331                                   MVT::SimpleValueType T2) {
332   // If the two types are the same, then they are the same, so they don't
333   // contradict.
334   if (T1 == T2) return false;
335 
336   // If either type is about iPtr, then they don't conflict unless the other
337   // one is not a scalar integer type.
338   if (T1 == MVT::iPTR)
339     return !MVT(T2).isInteger() || MVT(T2).isVector();
340 
341   if (T2 == MVT::iPTR)
342     return !MVT(T1).isInteger() || MVT(T1).isVector();
343 
344   // Otherwise, they are two different non-iPTR types, they conflict.
345   return true;
346 }
347 
348 bool CheckOpcodeMatcher::isContradictoryImpl(const Matcher *M) const {
349   if (const CheckOpcodeMatcher *COM = dyn_cast<CheckOpcodeMatcher>(M)) {
350     // One node can't have two different opcodes!
351     // Note: pointer equality isn't enough here, we have to check the enum names
352     // to ensure that the nodes are for the same opcode.
353     return COM->getOpcode().getEnumName() != getOpcode().getEnumName();
354   }
355 
356   // If the node has a known type, and if the type we're checking for is
357   // different, then we know they contradict.  For example, a check for
358   // ISD::STORE will never be true at the same time a check for Type i32 is.
359   if (const CheckTypeMatcher *CT = dyn_cast<CheckTypeMatcher>(M)) {
360     // If checking for a result the opcode doesn't have, it can't match.
361     if (CT->getResNo() >= getOpcode().getNumResults())
362       return true;
363 
364     MVT::SimpleValueType NodeType = getOpcode().getKnownType(CT->getResNo());
365     if (NodeType != MVT::Other)
366       return TypesAreContradictory(NodeType, CT->getType());
367   }
368 
369   return false;
370 }
371 
372 bool CheckTypeMatcher::isContradictoryImpl(const Matcher *M) const {
373   if (const CheckTypeMatcher *CT = dyn_cast<CheckTypeMatcher>(M))
374     return TypesAreContradictory(getType(), CT->getType());
375   return false;
376 }
377 
378 bool CheckChildTypeMatcher::isContradictoryImpl(const Matcher *M) const {
379   if (const CheckChildTypeMatcher *CC = dyn_cast<CheckChildTypeMatcher>(M)) {
380     // If the two checks are about different nodes, we don't know if they
381     // conflict!
382     if (CC->getChildNo() != getChildNo())
383       return false;
384 
385     return TypesAreContradictory(getType(), CC->getType());
386   }
387   return false;
388 }
389 
390 bool CheckIntegerMatcher::isContradictoryImpl(const Matcher *M) const {
391   if (const CheckIntegerMatcher *CIM = dyn_cast<CheckIntegerMatcher>(M))
392     return CIM->getValue() != getValue();
393   return false;
394 }
395 
396 bool CheckValueTypeMatcher::isContradictoryImpl(const Matcher *M) const {
397   if (const CheckValueTypeMatcher *CVT = dyn_cast<CheckValueTypeMatcher>(M))
398     return CVT->getTypeName() != getTypeName();
399   return false;
400 }
401 
402