1 //===-- llvm/Support/PatternMatch.h - Match on the LLVM IR ------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file provides a simple and efficient mechanism for performing general
11 // tree-based pattern matches on the LLVM IR. The power of these routines is
12 // that it allows you to write concise patterns that are expressive and easy to
13 // understand. The other major advantage of this is that it allows you to
14 // trivially capture/bind elements in the pattern to variables. For example,
15 // you can do something like this:
18 // Value *X, *Y; ConstantInt *C1, *C2; // (X & C1) | (Y & C2)
19 // if (match(Exp, m_Or(m_And(m_Value(X), m_ConstantInt(C1)),
20 // m_And(m_Value(Y), m_ConstantInt(C2))))) {
21 // ... Pattern is matched and variables are bound ...
24 // This is primarily useful to things like the instruction combiner, but can
25 // also be useful for static analysis tools or code generators.
27 //===----------------------------------------------------------------------===//
29 #ifndef LLVM_SUPPORT_PATTERNMATCH_H
30 #define LLVM_SUPPORT_PATTERNMATCH_H
32 #include "llvm/Constants.h"
33 #include "llvm/Instructions.h"
36 namespace PatternMatch {
38 template<typename Val, typename Pattern>
39 bool match(Val *V, const Pattern &P) {
40 return const_cast<Pattern&>(P).match(V);
43 template<typename Class>
45 template<typename ITy>
46 bool match(ITy *V) { return isa<Class>(V); }
49 /// m_Value() - Match an arbitrary value and ignore it.
50 inline leaf_ty<Value> m_Value() { return leaf_ty<Value>(); }
51 /// m_ConstantInt() - Match an arbitrary ConstantInt and ignore it.
52 inline leaf_ty<ConstantInt> m_ConstantInt() { return leaf_ty<ConstantInt>(); }
55 struct constantint_ty {
56 template<typename ITy>
58 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
59 const APInt &CIV = CI->getValue();
62 // If Val is negative, and CI is shorter than it, truncate to the right
63 // number of bits. If it is larger, then we have to sign extend. Just
64 // compare their negated values.
71 /// m_ConstantInt(int64_t) - Match a ConstantInt with a specific value
74 inline constantint_ty<Val> m_ConstantInt() {
75 return constantint_ty<Val>();
79 template<typename ITy>
81 if (const Constant *C = dyn_cast<Constant>(V))
82 return C->isNullValue();
87 /// m_Zero() - Match an arbitrary zero/null constant.
88 inline zero_ty m_Zero() { return zero_ty(); }
91 template<typename Class>
94 bind_ty(Class *&V) : VR(V) {}
96 template<typename ITy>
98 if (Class *CV = dyn_cast<Class>(V)) {
106 /// m_Value - Match a value, capturing it if we match.
107 inline bind_ty<Value> m_Value(Value *&V) { return V; }
109 /// m_ConstantInt - Match a ConstantInt, capturing the value if we match.
110 inline bind_ty<ConstantInt> m_ConstantInt(ConstantInt *&CI) { return CI; }
112 /// specificval_ty - Match a specified Value*.
113 struct specificval_ty {
115 specificval_ty(const Value *V) : Val(V) {}
117 template<typename ITy>
123 /// m_Specific - Match if we have a specific specified value.
124 inline specificval_ty m_Specific(const Value *V) { return V; }
127 //===----------------------------------------------------------------------===//
128 // Matchers for specific binary operators.
131 template<typename LHS_t, typename RHS_t,
132 unsigned Opcode, typename ConcreteTy = BinaryOperator>
133 struct BinaryOp_match {
137 BinaryOp_match(const LHS_t &LHS, const RHS_t &RHS) : L(LHS), R(RHS) {}
139 template<typename OpTy>
140 bool match(OpTy *V) {
141 if (V->getValueID() == Value::InstructionVal + Opcode) {
142 ConcreteTy *I = cast<ConcreteTy>(V);
143 return I->getOpcode() == Opcode && L.match(I->getOperand(0)) &&
144 R.match(I->getOperand(1));
146 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
147 return CE->getOpcode() == Opcode && L.match(CE->getOperand(0)) &&
148 R.match(CE->getOperand(1));
153 template<typename LHS, typename RHS>
154 inline BinaryOp_match<LHS, RHS, Instruction::Add> m_Add(const LHS &L,
156 return BinaryOp_match<LHS, RHS, Instruction::Add>(L, R);
159 template<typename LHS, typename RHS>
160 inline BinaryOp_match<LHS, RHS, Instruction::Sub> m_Sub(const LHS &L,
162 return BinaryOp_match<LHS, RHS, Instruction::Sub>(L, R);
165 template<typename LHS, typename RHS>
166 inline BinaryOp_match<LHS, RHS, Instruction::Mul> m_Mul(const LHS &L,
168 return BinaryOp_match<LHS, RHS, Instruction::Mul>(L, R);
171 template<typename LHS, typename RHS>
172 inline BinaryOp_match<LHS, RHS, Instruction::UDiv> m_UDiv(const LHS &L,
174 return BinaryOp_match<LHS, RHS, Instruction::UDiv>(L, R);
177 template<typename LHS, typename RHS>
178 inline BinaryOp_match<LHS, RHS, Instruction::SDiv> m_SDiv(const LHS &L,
180 return BinaryOp_match<LHS, RHS, Instruction::SDiv>(L, R);
183 template<typename LHS, typename RHS>
184 inline BinaryOp_match<LHS, RHS, Instruction::FDiv> m_FDiv(const LHS &L,
186 return BinaryOp_match<LHS, RHS, Instruction::FDiv>(L, R);
189 template<typename LHS, typename RHS>
190 inline BinaryOp_match<LHS, RHS, Instruction::URem> m_URem(const LHS &L,
192 return BinaryOp_match<LHS, RHS, Instruction::URem>(L, R);
195 template<typename LHS, typename RHS>
196 inline BinaryOp_match<LHS, RHS, Instruction::SRem> m_SRem(const LHS &L,
198 return BinaryOp_match<LHS, RHS, Instruction::SRem>(L, R);
201 template<typename LHS, typename RHS>
202 inline BinaryOp_match<LHS, RHS, Instruction::FRem> m_FRem(const LHS &L,
204 return BinaryOp_match<LHS, RHS, Instruction::FRem>(L, R);
207 template<typename LHS, typename RHS>
208 inline BinaryOp_match<LHS, RHS, Instruction::And> m_And(const LHS &L,
210 return BinaryOp_match<LHS, RHS, Instruction::And>(L, R);
213 template<typename LHS, typename RHS>
214 inline BinaryOp_match<LHS, RHS, Instruction::Or> m_Or(const LHS &L,
216 return BinaryOp_match<LHS, RHS, Instruction::Or>(L, R);
219 template<typename LHS, typename RHS>
220 inline BinaryOp_match<LHS, RHS, Instruction::Xor> m_Xor(const LHS &L,
222 return BinaryOp_match<LHS, RHS, Instruction::Xor>(L, R);
225 template<typename LHS, typename RHS>
226 inline BinaryOp_match<LHS, RHS, Instruction::Shl> m_Shl(const LHS &L,
228 return BinaryOp_match<LHS, RHS, Instruction::Shl>(L, R);
231 template<typename LHS, typename RHS>
232 inline BinaryOp_match<LHS, RHS, Instruction::LShr> m_LShr(const LHS &L,
234 return BinaryOp_match<LHS, RHS, Instruction::LShr>(L, R);
237 template<typename LHS, typename RHS>
238 inline BinaryOp_match<LHS, RHS, Instruction::AShr> m_AShr(const LHS &L,
240 return BinaryOp_match<LHS, RHS, Instruction::AShr>(L, R);
243 //===----------------------------------------------------------------------===//
244 // Matchers for either AShr or LShr .. for convenience
246 template<typename LHS_t, typename RHS_t, typename ConcreteTy = BinaryOperator>
251 Shr_match(const LHS_t &LHS, const RHS_t &RHS) : L(LHS), R(RHS) {}
253 template<typename OpTy>
254 bool match(OpTy *V) {
255 if (V->getValueID() == Value::InstructionVal + Instruction::LShr ||
256 V->getValueID() == Value::InstructionVal + Instruction::AShr) {
257 ConcreteTy *I = cast<ConcreteTy>(V);
258 return (I->getOpcode() == Instruction::AShr ||
259 I->getOpcode() == Instruction::LShr) &&
260 L.match(I->getOperand(0)) &&
261 R.match(I->getOperand(1));
263 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
264 return (CE->getOpcode() == Instruction::LShr ||
265 CE->getOpcode() == Instruction::AShr) &&
266 L.match(CE->getOperand(0)) &&
267 R.match(CE->getOperand(1));
272 template<typename LHS, typename RHS>
273 inline Shr_match<LHS, RHS> m_Shr(const LHS &L, const RHS &R) {
274 return Shr_match<LHS, RHS>(L, R);
277 //===----------------------------------------------------------------------===//
278 // Matchers for binary classes
281 template<typename LHS_t, typename RHS_t, typename Class, typename OpcType>
282 struct BinaryOpClass_match {
287 BinaryOpClass_match(OpcType &Op, const LHS_t &LHS,
289 : Opcode(&Op), L(LHS), R(RHS) {}
290 BinaryOpClass_match(const LHS_t &LHS, const RHS_t &RHS)
291 : Opcode(0), L(LHS), R(RHS) {}
293 template<typename OpTy>
294 bool match(OpTy *V) {
295 if (Class *I = dyn_cast<Class>(V))
296 if (L.match(I->getOperand(0)) && R.match(I->getOperand(1))) {
298 *Opcode = I->getOpcode();
301 #if 0 // Doesn't handle constantexprs yet!
302 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
303 return CE->getOpcode() == Opcode && L.match(CE->getOperand(0)) &&
304 R.match(CE->getOperand(1));
310 template<typename LHS, typename RHS>
311 inline BinaryOpClass_match<LHS, RHS, BinaryOperator, Instruction::BinaryOps>
312 m_Shift(Instruction::BinaryOps &Op, const LHS &L, const RHS &R) {
313 return BinaryOpClass_match<LHS, RHS,
314 BinaryOperator, Instruction::BinaryOps>(Op, L, R);
317 template<typename LHS, typename RHS>
318 inline BinaryOpClass_match<LHS, RHS, BinaryOperator, Instruction::BinaryOps>
319 m_Shift(const LHS &L, const RHS &R) {
320 return BinaryOpClass_match<LHS, RHS,
321 BinaryOperator, Instruction::BinaryOps>(L, R);
324 //===----------------------------------------------------------------------===//
325 // Matchers for CmpInst classes
328 template<typename LHS_t, typename RHS_t, typename Class, typename PredicateTy>
329 struct CmpClass_match {
330 PredicateTy &Predicate;
334 CmpClass_match(PredicateTy &Pred, const LHS_t &LHS,
336 : Predicate(Pred), L(LHS), R(RHS) {}
338 template<typename OpTy>
339 bool match(OpTy *V) {
340 if (Class *I = dyn_cast<Class>(V))
341 if (L.match(I->getOperand(0)) && R.match(I->getOperand(1))) {
342 Predicate = I->getPredicate();
349 template<typename LHS, typename RHS>
350 inline CmpClass_match<LHS, RHS, ICmpInst, ICmpInst::Predicate>
351 m_ICmp(ICmpInst::Predicate &Pred, const LHS &L, const RHS &R) {
352 return CmpClass_match<LHS, RHS,
353 ICmpInst, ICmpInst::Predicate>(Pred, L, R);
356 template<typename LHS, typename RHS>
357 inline CmpClass_match<LHS, RHS, FCmpInst, FCmpInst::Predicate>
358 m_FCmp(FCmpInst::Predicate &Pred, const LHS &L, const RHS &R) {
359 return CmpClass_match<LHS, RHS,
360 FCmpInst, FCmpInst::Predicate>(Pred, L, R);
363 //===----------------------------------------------------------------------===//
364 // Matchers for SelectInst classes
367 template<typename Cond_t, typename LHS_t, typename RHS_t>
368 struct SelectClass_match {
373 SelectClass_match(const Cond_t &Cond, const LHS_t &LHS,
375 : C(Cond), L(LHS), R(RHS) {}
377 template<typename OpTy>
378 bool match(OpTy *V) {
379 if (SelectInst *I = dyn_cast<SelectInst>(V))
380 return C.match(I->getOperand(0)) &&
381 L.match(I->getOperand(1)) &&
382 R.match(I->getOperand(2));
387 template<typename Cond, typename LHS, typename RHS>
388 inline SelectClass_match<Cond, RHS, LHS>
389 m_Select(const Cond &C, const LHS &L, const RHS &R) {
390 return SelectClass_match<Cond, LHS, RHS>(C, L, R);
393 /// m_SelectCst - This matches a select of two constants, e.g.:
394 /// m_SelectCst(m_Value(V), -1, 0)
395 template<int64_t L, int64_t R, typename Cond>
396 inline SelectClass_match<Cond, constantint_ty<L>, constantint_ty<R> >
397 m_SelectCst(const Cond &C) {
398 return SelectClass_match<Cond, constantint_ty<L>,
399 constantint_ty<R> >(C, m_ConstantInt<L>(),
404 //===----------------------------------------------------------------------===//
405 // Matchers for CastInst classes
408 template<typename Op_t, typename Class>
409 struct CastClass_match {
412 CastClass_match(const Op_t &OpMatch) : Op(OpMatch) {}
414 template<typename OpTy>
415 bool match(OpTy *V) {
416 if (Class *I = dyn_cast<Class>(V))
417 return Op.match(I->getOperand(0));
422 template<typename Class, typename OpTy>
423 inline CastClass_match<OpTy, Class> m_Cast(const OpTy &Op) {
424 return CastClass_match<OpTy, Class>(Op);
428 //===----------------------------------------------------------------------===//
429 // Matchers for unary operators
432 template<typename LHS_t>
436 not_match(const LHS_t &LHS) : L(LHS) {}
438 template<typename OpTy>
439 bool match(OpTy *V) {
440 if (Instruction *I = dyn_cast<Instruction>(V))
441 if (I->getOpcode() == Instruction::Xor)
442 return matchIfNot(I->getOperand(0), I->getOperand(1));
443 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
444 if (CE->getOpcode() == Instruction::Xor)
445 return matchIfNot(CE->getOperand(0), CE->getOperand(1));
446 if (ConstantInt *CI = dyn_cast<ConstantInt>(V))
447 return L.match(ConstantExpr::getNot(CI));
451 bool matchIfNot(Value *LHS, Value *RHS) {
452 if (ConstantInt *CI = dyn_cast<ConstantInt>(RHS))
453 return CI->isAllOnesValue() && L.match(LHS);
454 if (ConstantInt *CI = dyn_cast<ConstantInt>(LHS))
455 return CI->isAllOnesValue() && L.match(RHS);
456 if (ConstantVector *CV = dyn_cast<ConstantVector>(RHS))
457 return CV->isAllOnesValue() && L.match(LHS);
458 if (ConstantVector *CV = dyn_cast<ConstantVector>(LHS))
459 return CV->isAllOnesValue() && L.match(RHS);
464 template<typename LHS>
465 inline not_match<LHS> m_Not(const LHS &L) { return L; }
468 template<typename LHS_t>
472 neg_match(const LHS_t &LHS) : L(LHS) {}
474 template<typename OpTy>
475 bool match(OpTy *V) {
476 if (Instruction *I = dyn_cast<Instruction>(V))
477 if (I->getOpcode() == Instruction::Sub)
478 return matchIfNeg(I->getOperand(0), I->getOperand(1));
479 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
480 if (CE->getOpcode() == Instruction::Sub)
481 return matchIfNeg(CE->getOperand(0), CE->getOperand(1));
482 if (ConstantInt *CI = dyn_cast<ConstantInt>(V))
483 return L.match(ConstantExpr::getNeg(CI));
487 bool matchIfNeg(Value *LHS, Value *RHS) {
488 return LHS == ConstantExpr::getZeroValueForNegationExpr(LHS->getType()) &&
493 template<typename LHS>
494 inline neg_match<LHS> m_Neg(const LHS &L) { return L; }
497 //===----------------------------------------------------------------------===//
498 // Matchers for control flow
501 template<typename Cond_t>
505 brc_match(const Cond_t &C, BasicBlock *&t, BasicBlock *&f)
506 : Cond(C), T(t), F(f) {
509 template<typename OpTy>
510 bool match(OpTy *V) {
511 if (BranchInst *BI = dyn_cast<BranchInst>(V))
512 if (BI->isConditional()) {
513 if (Cond.match(BI->getCondition())) {
514 T = BI->getSuccessor(0);
515 F = BI->getSuccessor(1);
523 template<typename Cond_t>
524 inline brc_match<Cond_t> m_Br(const Cond_t &C, BasicBlock *&T, BasicBlock *&F) {
525 return brc_match<Cond_t>(C, T, F);
528 } // end namespace PatternMatch
529 } // end namespace llvm