Home | History | Annotate | Download | only in Support 
      1 //===-- llvm/Support/PatternMatch.h - Match on the LLVM IR ------*- C++ -*-===//
      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 // 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:
     16 //
     17 //  Value *Exp = ...
     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 ...
     22 //  }
     23 //
     24 // This is primarily useful to things like the instruction combiner, but can
     25 // also be useful for static analysis tools or code generators.
     26 //
     27 //===----------------------------------------------------------------------===//
     28 
     29 #ifndef LLVM_SUPPORT_PATTERNMATCH_H
     30 #define LLVM_SUPPORT_PATTERNMATCH_H
     31 
     32 #include "llvm/IR/Constants.h"
     33 #include "llvm/IR/Instructions.h"
     34 #include "llvm/IR/IntrinsicInst.h"
     35 #include "llvm/IR/Operator.h"
     36 #include "llvm/Support/CallSite.h"
     37 
     38 namespace llvm {
     39 namespace PatternMatch {
     40 
     41 template<typename Val, typename Pattern>
     42 bool match(Val *V, const Pattern &P) {
     43   return const_cast<Pattern&>(P).match(V);
     44 }
     45 
     46 
     47 template<typename SubPattern_t>
     48 struct OneUse_match {
     49   SubPattern_t SubPattern;
     50 
     51   OneUse_match(const SubPattern_t &SP) : SubPattern(SP) {}
     52 
     53   template<typename OpTy>
     54   bool match(OpTy *V) {
     55     return V->hasOneUse() && SubPattern.match(V);
     56   }
     57 };
     58 
     59 template<typename T>
     60 inline OneUse_match<T> m_OneUse(const T &SubPattern) { return SubPattern; }
     61 
     62 
     63 template<typename Class>
     64 struct class_match {
     65   template<typename ITy>
     66   bool match(ITy *V) { return isa<Class>(V); }
     67 };
     68 
     69 /// m_Value() - Match an arbitrary value and ignore it.
     70 inline class_match<Value> m_Value() { return class_match<Value>(); }
     71 /// m_ConstantInt() - Match an arbitrary ConstantInt and ignore it.
     72 inline class_match<ConstantInt> m_ConstantInt() {
     73   return class_match<ConstantInt>();
     74 }
     75 /// m_Undef() - Match an arbitrary undef constant.
     76 inline class_match<UndefValue> m_Undef() { return class_match<UndefValue>(); }
     77 
     78 inline class_match<Constant> m_Constant() { return class_match<Constant>(); }
     79 
     80 /// Matching combinators
     81 template<typename LTy, typename RTy>
     82 struct match_combine_or {
     83   LTy L;
     84   RTy R;
     85 
     86   match_combine_or(const LTy &Left, const RTy &Right) : L(Left), R(Right) { }
     87 
     88   template<typename ITy>
     89   bool match(ITy *V) {
     90     if (L.match(V))
     91       return true;
     92     if (R.match(V))
     93       return true;
     94     return false;
     95   }
     96 };
     97 
     98 template<typename LTy, typename RTy>
     99 struct match_combine_and {
    100   LTy L;
    101   RTy R;
    102 
    103   match_combine_and(const LTy &Left, const RTy &Right) : L(Left), R(Right) { }
    104 
    105   template<typename ITy>
    106   bool match(ITy *V) {
    107     if (L.match(V))
    108       if (R.match(V))
    109         return true;
    110     return false;
    111   }
    112 };
    113 
    114 /// Combine two pattern matchers matching L || R
    115 template<typename LTy, typename RTy>
    116 inline match_combine_or<LTy, RTy> m_CombineOr(const LTy &L, const RTy &R) {
    117   return match_combine_or<LTy, RTy>(L, R);
    118 }
    119 
    120 /// Combine two pattern matchers matching L && R
    121 template<typename LTy, typename RTy>
    122 inline match_combine_and<LTy, RTy> m_CombineAnd(const LTy &L, const RTy &R) {
    123   return match_combine_and<LTy, RTy>(L, R);
    124 }
    125 
    126 struct match_zero {
    127   template<typename ITy>
    128   bool match(ITy *V) {
    129     if (const Constant *C = dyn_cast<Constant>(V))
    130       return C->isNullValue();
    131     return false;
    132   }
    133 };
    134 
    135 /// m_Zero() - Match an arbitrary zero/null constant.  This includes
    136 /// zero_initializer for vectors and ConstantPointerNull for pointers.
    137 inline match_zero m_Zero() { return match_zero(); }
    138 
    139 struct match_neg_zero {
    140   template<typename ITy>
    141   bool match(ITy *V) {
    142     if (const Constant *C = dyn_cast<Constant>(V))
    143       return C->isNegativeZeroValue();
    144     return false;
    145   }
    146 };
    147 
    148 /// m_NegZero() - Match an arbitrary zero/null constant.  This includes
    149 /// zero_initializer for vectors and ConstantPointerNull for pointers. For
    150 /// floating point constants, this will match negative zero but not positive
    151 /// zero
    152 inline match_neg_zero m_NegZero() { return match_neg_zero(); }
    153 
    154 /// m_AnyZero() - Match an arbitrary zero/null constant.  This includes
    155 /// zero_initializer for vectors and ConstantPointerNull for pointers. For
    156 /// floating point constants, this will match negative zero and positive zero
    157 inline match_combine_or<match_zero, match_neg_zero> m_AnyZero() {
    158   return m_CombineOr(m_Zero(), m_NegZero());
    159 }
    160 
    161 struct apint_match {
    162   const APInt *&Res;
    163   apint_match(const APInt *&R) : Res(R) {}
    164   template<typename ITy>
    165   bool match(ITy *V) {
    166     if (ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
    167       Res = &CI->getValue();
    168       return true;
    169     }
    170     if (V->getType()->isVectorTy())
    171       if (const Constant *C = dyn_cast<Constant>(V))
    172         if (ConstantInt *CI =
    173             dyn_cast_or_null<ConstantInt>(C->getSplatValue())) {
    174           Res = &CI->getValue();
    175           return true;
    176         }
    177     return false;
    178   }
    179 };
    180 
    181 /// m_APInt - Match a ConstantInt or splatted ConstantVector, binding the
    182 /// specified pointer to the contained APInt.
    183 inline apint_match m_APInt(const APInt *&Res) { return Res; }
    184 
    185 
    186 template<int64_t Val>
    187 struct constantint_match {
    188   template<typename ITy>
    189   bool match(ITy *V) {
    190     if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
    191       const APInt &CIV = CI->getValue();
    192       if (Val >= 0)
    193         return CIV == static_cast<uint64_t>(Val);
    194       // If Val is negative, and CI is shorter than it, truncate to the right
    195       // number of bits.  If it is larger, then we have to sign extend.  Just
    196       // compare their negated values.
    197       return -CIV == -Val;
    198     }
    199     return false;
    200   }
    201 };
    202 
    203 /// m_ConstantInt<int64_t> - Match a ConstantInt with a specific value.
    204 template<int64_t Val>
    205 inline constantint_match<Val> m_ConstantInt() {
    206   return constantint_match<Val>();
    207 }
    208 
    209 /// cst_pred_ty - This helper class is used to match scalar and vector constants
    210 /// that satisfy a specified predicate.
    211 template<typename Predicate>
    212 struct cst_pred_ty : public Predicate {
    213   template<typename ITy>
    214   bool match(ITy *V) {
    215     if (const ConstantInt *CI = dyn_cast<ConstantInt>(V))
    216       return this->isValue(CI->getValue());
    217     if (V->getType()->isVectorTy())
    218       if (const Constant *C = dyn_cast<Constant>(V))
    219         if (const ConstantInt *CI =
    220             dyn_cast_or_null<ConstantInt>(C->getSplatValue()))
    221           return this->isValue(CI->getValue());
    222     return false;
    223   }
    224 };
    225 
    226 /// api_pred_ty - This helper class is used to match scalar and vector constants
    227 /// that satisfy a specified predicate, and bind them to an APInt.
    228 template<typename Predicate>
    229 struct api_pred_ty : public Predicate {
    230   const APInt *&Res;
    231   api_pred_ty(const APInt *&R) : Res(R) {}
    232   template<typename ITy>
    233   bool match(ITy *V) {
    234     if (const ConstantInt *CI = dyn_cast<ConstantInt>(V))
    235       if (this->isValue(CI->getValue())) {
    236         Res = &CI->getValue();
    237         return true;
    238       }
    239     if (V->getType()->isVectorTy())
    240       if (const Constant *C = dyn_cast<Constant>(V))
    241         if (ConstantInt *CI = dyn_cast_or_null<ConstantInt>(C->getSplatValue()))
    242           if (this->isValue(CI->getValue())) {
    243             Res = &CI->getValue();
    244             return true;
    245           }
    246 
    247     return false;
    248   }
    249 };
    250 
    251 
    252 struct is_one {
    253   bool isValue(const APInt &C) { return C == 1; }
    254 };
    255 
    256 /// m_One() - Match an integer 1 or a vector with all elements equal to 1.
    257 inline cst_pred_ty<is_one> m_One() { return cst_pred_ty<is_one>(); }
    258 inline api_pred_ty<is_one> m_One(const APInt *&V) { return V; }
    259 
    260 struct is_all_ones {
    261   bool isValue(const APInt &C) { return C.isAllOnesValue(); }
    262 };
    263 
    264 /// m_AllOnes() - Match an integer or vector with all bits set to true.
    265 inline cst_pred_ty<is_all_ones> m_AllOnes() {return cst_pred_ty<is_all_ones>();}
    266 inline api_pred_ty<is_all_ones> m_AllOnes(const APInt *&V) { return V; }
    267 
    268 struct is_sign_bit {
    269   bool isValue(const APInt &C) { return C.isSignBit(); }
    270 };
    271 
    272 /// m_SignBit() - Match an integer or vector with only the sign bit(s) set.
    273 inline cst_pred_ty<is_sign_bit> m_SignBit() {return cst_pred_ty<is_sign_bit>();}
    274 inline api_pred_ty<is_sign_bit> m_SignBit(const APInt *&V) { return V; }
    275 
    276 struct is_power2 {
    277   bool isValue(const APInt &C) { return C.isPowerOf2(); }
    278 };
    279 
    280 /// m_Power2() - Match an integer or vector power of 2.
    281 inline cst_pred_ty<is_power2> m_Power2() { return cst_pred_ty<is_power2>(); }
    282 inline api_pred_ty<is_power2> m_Power2(const APInt *&V) { return V; }
    283 
    284 template<typename Class>
    285 struct bind_ty {
    286   Class *&VR;
    287   bind_ty(Class *&V) : VR(V) {}
    288 
    289   template<typename ITy>
    290   bool match(ITy *V) {
    291     if (Class *CV = dyn_cast<Class>(V)) {
    292       VR = CV;
    293       return true;
    294     }
    295     return false;
    296   }
    297 };
    298 
    299 /// m_Value - Match a value, capturing it if we match.
    300 inline bind_ty<Value> m_Value(Value *&V) { return V; }
    301 
    302 /// m_ConstantInt - Match a ConstantInt, capturing the value if we match.
    303 inline bind_ty<ConstantInt> m_ConstantInt(ConstantInt *&CI) { return CI; }
    304 
    305 /// m_Constant - Match a Constant, capturing the value if we match.
    306 inline bind_ty<Constant> m_Constant(Constant *&C) { return C; }
    307 
    308 /// m_ConstantFP - Match a ConstantFP, capturing the value if we match.
    309 inline bind_ty<ConstantFP> m_ConstantFP(ConstantFP *&C) { return C; }
    310 
    311 /// specificval_ty - Match a specified Value*.
    312 struct specificval_ty {
    313   const Value *Val;
    314   specificval_ty(const Value *V) : Val(V) {}
    315 
    316   template<typename ITy>
    317   bool match(ITy *V) {
    318     return V == Val;
    319   }
    320 };
    321 
    322 /// m_Specific - Match if we have a specific specified value.
    323 inline specificval_ty m_Specific(const Value *V) { return V; }
    324 
    325 /// Match a specified floating point value or vector of all elements of that
    326 /// value.
    327 struct specific_fpval {
    328   double Val;
    329   specific_fpval(double V) : Val(V) {}
    330 
    331   template<typename ITy>
    332   bool match(ITy *V) {
    333     if (const ConstantFP *CFP = dyn_cast<ConstantFP>(V))
    334       return CFP->isExactlyValue(Val);
    335     if (V->getType()->isVectorTy())
    336       if (const Constant *C = dyn_cast<Constant>(V))
    337         if (ConstantFP *CFP = dyn_cast_or_null<ConstantFP>(C->getSplatValue()))
    338           return CFP->isExactlyValue(Val);
    339     return false;
    340   }
    341 };
    342 
    343 /// Match a specific floating point value or vector with all elements equal to
    344 /// the value.
    345 inline specific_fpval m_SpecificFP(double V) { return specific_fpval(V); }
    346 
    347 /// Match a float 1.0 or vector with all elements equal to 1.0.
    348 inline specific_fpval m_FPOne() { return m_SpecificFP(1.0); }
    349 
    350 struct bind_const_intval_ty {
    351   uint64_t &VR;
    352   bind_const_intval_ty(uint64_t &V) : VR(V) {}
    353 
    354   template<typename ITy>
    355   bool match(ITy *V) {
    356     if (ConstantInt *CV = dyn_cast<ConstantInt>(V))
    357       if (CV->getBitWidth() <= 64) {
    358         VR = CV->getZExtValue();
    359         return true;
    360       }
    361     return false;
    362   }
    363 };
    364 
    365 /// m_ConstantInt - Match a ConstantInt and bind to its value.  This does not
    366 /// match ConstantInts wider than 64-bits.
    367 inline bind_const_intval_ty m_ConstantInt(uint64_t &V) { return V; }
    368 
    369 //===----------------------------------------------------------------------===//
    370 // Matchers for specific binary operators.
    371 //
    372 
    373 template<typename LHS_t, typename RHS_t, unsigned Opcode>
    374 struct BinaryOp_match {
    375   LHS_t L;
    376   RHS_t R;
    377 
    378   BinaryOp_match(const LHS_t &LHS, const RHS_t &RHS) : L(LHS), R(RHS) {}
    379 
    380   template<typename OpTy>
    381   bool match(OpTy *V) {
    382     if (V->getValueID() == Value::InstructionVal + Opcode) {
    383       BinaryOperator *I = cast<BinaryOperator>(V);
    384       return L.match(I->getOperand(0)) && R.match(I->getOperand(1));
    385     }
    386     if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
    387       return CE->getOpcode() == Opcode && L.match(CE->getOperand(0)) &&
    388              R.match(CE->getOperand(1));
    389     return false;
    390   }
    391 };
    392 
    393 template<typename LHS, typename RHS>
    394 inline BinaryOp_match<LHS, RHS, Instruction::Add>
    395 m_Add(const LHS &L, const RHS &R) {
    396   return BinaryOp_match<LHS, RHS, Instruction::Add>(L, R);
    397 }
    398 
    399 template<typename LHS, typename RHS>
    400 inline BinaryOp_match<LHS, RHS, Instruction::FAdd>
    401 m_FAdd(const LHS &L, const RHS &R) {
    402   return BinaryOp_match<LHS, RHS, Instruction::FAdd>(L, R);
    403 }
    404 
    405 template<typename LHS, typename RHS>
    406 inline BinaryOp_match<LHS, RHS, Instruction::Sub>
    407 m_Sub(const LHS &L, const RHS &R) {
    408   return BinaryOp_match<LHS, RHS, Instruction::Sub>(L, R);
    409 }
    410 
    411 template<typename LHS, typename RHS>
    412 inline BinaryOp_match<LHS, RHS, Instruction::FSub>
    413 m_FSub(const LHS &L, const RHS &R) {
    414   return BinaryOp_match<LHS, RHS, Instruction::FSub>(L, R);
    415 }
    416 
    417 template<typename LHS, typename RHS>
    418 inline BinaryOp_match<LHS, RHS, Instruction::Mul>
    419 m_Mul(const LHS &L, const RHS &R) {
    420   return BinaryOp_match<LHS, RHS, Instruction::Mul>(L, R);
    421 }
    422 
    423 template<typename LHS, typename RHS>
    424 inline BinaryOp_match<LHS, RHS, Instruction::FMul>
    425 m_FMul(const LHS &L, const RHS &R) {
    426   return BinaryOp_match<LHS, RHS, Instruction::FMul>(L, R);
    427 }
    428 
    429 template<typename LHS, typename RHS>
    430 inline BinaryOp_match<LHS, RHS, Instruction::UDiv>
    431 m_UDiv(const LHS &L, const RHS &R) {
    432   return BinaryOp_match<LHS, RHS, Instruction::UDiv>(L, R);
    433 }
    434 
    435 template<typename LHS, typename RHS>
    436 inline BinaryOp_match<LHS, RHS, Instruction::SDiv>
    437 m_SDiv(const LHS &L, const RHS &R) {
    438   return BinaryOp_match<LHS, RHS, Instruction::SDiv>(L, R);
    439 }
    440 
    441 template<typename LHS, typename RHS>
    442 inline BinaryOp_match<LHS, RHS, Instruction::FDiv>
    443 m_FDiv(const LHS &L, const RHS &R) {
    444   return BinaryOp_match<LHS, RHS, Instruction::FDiv>(L, R);
    445 }
    446 
    447 template<typename LHS, typename RHS>
    448 inline BinaryOp_match<LHS, RHS, Instruction::URem>
    449 m_URem(const LHS &L, const RHS &R) {
    450   return BinaryOp_match<LHS, RHS, Instruction::URem>(L, R);
    451 }
    452 
    453 template<typename LHS, typename RHS>
    454 inline BinaryOp_match<LHS, RHS, Instruction::SRem>
    455 m_SRem(const LHS &L, const RHS &R) {
    456   return BinaryOp_match<LHS, RHS, Instruction::SRem>(L, R);
    457 }
    458 
    459 template<typename LHS, typename RHS>
    460 inline BinaryOp_match<LHS, RHS, Instruction::FRem>
    461 m_FRem(const LHS &L, const RHS &R) {
    462   return BinaryOp_match<LHS, RHS, Instruction::FRem>(L, R);
    463 }
    464 
    465 template<typename LHS, typename RHS>
    466 inline BinaryOp_match<LHS, RHS, Instruction::And>
    467 m_And(const LHS &L, const RHS &R) {
    468   return BinaryOp_match<LHS, RHS, Instruction::And>(L, R);
    469 }
    470 
    471 template<typename LHS, typename RHS>
    472 inline BinaryOp_match<LHS, RHS, Instruction::Or>
    473 m_Or(const LHS &L, const RHS &R) {
    474   return BinaryOp_match<LHS, RHS, Instruction::Or>(L, R);
    475 }
    476 
    477 template<typename LHS, typename RHS>
    478 inline BinaryOp_match<LHS, RHS, Instruction::Xor>
    479 m_Xor(const LHS &L, const RHS &R) {
    480   return BinaryOp_match<LHS, RHS, Instruction::Xor>(L, R);
    481 }
    482 
    483 template<typename LHS, typename RHS>
    484 inline BinaryOp_match<LHS, RHS, Instruction::Shl>
    485 m_Shl(const LHS &L, const RHS &R) {
    486   return BinaryOp_match<LHS, RHS, Instruction::Shl>(L, R);
    487 }
    488 
    489 template<typename LHS, typename RHS>
    490 inline BinaryOp_match<LHS, RHS, Instruction::LShr>
    491 m_LShr(const LHS &L, const RHS &R) {
    492   return BinaryOp_match<LHS, RHS, Instruction::LShr>(L, R);
    493 }
    494 
    495 template<typename LHS, typename RHS>
    496 inline BinaryOp_match<LHS, RHS, Instruction::AShr>
    497 m_AShr(const LHS &L, const RHS &R) {
    498   return BinaryOp_match<LHS, RHS, Instruction::AShr>(L, R);
    499 }
    500 
    501 //===----------------------------------------------------------------------===//
    502 // Class that matches two different binary ops.
    503 //
    504 template<typename LHS_t, typename RHS_t, unsigned Opc1, unsigned Opc2>
    505 struct BinOp2_match {
    506   LHS_t L;
    507   RHS_t R;
    508 
    509   BinOp2_match(const LHS_t &LHS, const RHS_t &RHS) : L(LHS), R(RHS) {}
    510 
    511   template<typename OpTy>
    512   bool match(OpTy *V) {
    513     if (V->getValueID() == Value::InstructionVal + Opc1 ||
    514         V->getValueID() == Value::InstructionVal + Opc2) {
    515       BinaryOperator *I = cast<BinaryOperator>(V);
    516       return L.match(I->getOperand(0)) && R.match(I->getOperand(1));
    517     }
    518     if (ConstantExpr *CE = dyn_cast<ConstantExpr>(V))
    519       return (CE->getOpcode() == Opc1 || CE->getOpcode() == Opc2) &&
    520              L.match(CE->getOperand(0)) && R.match(CE->getOperand(1));
    521     return false;
    522   }
    523 };
    524 
    525 /// m_Shr - Matches LShr or AShr.
    526 template<typename LHS, typename RHS>
    527 inline BinOp2_match<LHS, RHS, Instruction::LShr, Instruction::AShr>
    528 m_Shr(const LHS &L, const RHS &R) {
    529   return BinOp2_match<LHS, RHS, Instruction::LShr, Instruction::AShr>(L, R);
    530 }
    531 
    532 /// m_LogicalShift - Matches LShr or Shl.
    533 template<typename LHS, typename RHS>
    534 inline BinOp2_match<LHS, RHS, Instruction::LShr, Instruction::Shl>
    535 m_LogicalShift(const LHS &L, const RHS &R) {
    536   return BinOp2_match<LHS, RHS, Instruction::LShr, Instruction::Shl>(L, R);
    537 }
    538 
    539 /// m_IDiv - Matches UDiv and SDiv.
    540 template<typename LHS, typename RHS>
    541 inline BinOp2_match<LHS, RHS, Instruction::SDiv, Instruction::UDiv>
    542 m_IDiv(const LHS &L, const RHS &R) {
    543   return BinOp2_match<LHS, RHS, Instruction::SDiv, Instruction::UDiv>(L, R);
    544 }
    545 
    546 //===----------------------------------------------------------------------===//
    547 // Class that matches exact binary ops.
    548 //
    549 template<typename SubPattern_t>
    550 struct Exact_match {
    551   SubPattern_t SubPattern;
    552 
    553   Exact_match(const SubPattern_t &SP) : SubPattern(SP) {}
    554 
    555   template<typename OpTy>
    556   bool match(OpTy *V) {
    557     if (PossiblyExactOperator *PEO = dyn_cast<PossiblyExactOperator>(V))
    558       return PEO->isExact() && SubPattern.match(V);
    559     return false;
    560   }
    561 };
    562 
    563 template<typename T>
    564 inline Exact_match<T> m_Exact(const T &SubPattern) { return SubPattern; }
    565 
    566 //===----------------------------------------------------------------------===//
    567 // Matchers for CmpInst classes
    568 //
    569 
    570 template<typename LHS_t, typename RHS_t, typename Class, typename PredicateTy>
    571 struct CmpClass_match {
    572   PredicateTy &Predicate;
    573   LHS_t L;
    574   RHS_t R;
    575 
    576   CmpClass_match(PredicateTy &Pred, const LHS_t &LHS, const RHS_t &RHS)
    577     : Predicate(Pred), L(LHS), R(RHS) {}
    578 
    579   template<typename OpTy>
    580   bool match(OpTy *V) {
    581     if (Class *I = dyn_cast<Class>(V))
    582       if (L.match(I->getOperand(0)) && R.match(I->getOperand(1))) {
    583         Predicate = I->getPredicate();
    584         return true;
    585       }
    586     return false;
    587   }
    588 };
    589 
    590 template<typename LHS, typename RHS>
    591 inline CmpClass_match<LHS, RHS, ICmpInst, ICmpInst::Predicate>
    592 m_ICmp(ICmpInst::Predicate &Pred, const LHS &L, const RHS &R) {
    593   return CmpClass_match<LHS, RHS,
    594                         ICmpInst, ICmpInst::Predicate>(Pred, L, R);
    595 }
    596 
    597 template<typename LHS, typename RHS>
    598 inline CmpClass_match<LHS, RHS, FCmpInst, FCmpInst::Predicate>
    599 m_FCmp(FCmpInst::Predicate &Pred, const LHS &L, const RHS &R) {
    600   return CmpClass_match<LHS, RHS,
    601                         FCmpInst, FCmpInst::Predicate>(Pred, L, R);
    602 }
    603 
    604 //===----------------------------------------------------------------------===//
    605 // Matchers for SelectInst classes
    606 //
    607 
    608 template<typename Cond_t, typename LHS_t, typename RHS_t>
    609 struct SelectClass_match {
    610   Cond_t C;
    611   LHS_t L;
    612   RHS_t R;
    613 
    614   SelectClass_match(const Cond_t &Cond, const LHS_t &LHS,
    615                     const RHS_t &RHS)
    616     : C(Cond), L(LHS), R(RHS) {}
    617 
    618   template<typename OpTy>
    619   bool match(OpTy *V) {
    620     if (SelectInst *I = dyn_cast<SelectInst>(V))
    621       return C.match(I->getOperand(0)) &&
    622              L.match(I->getOperand(1)) &&
    623              R.match(I->getOperand(2));
    624     return false;
    625   }
    626 };
    627 
    628 template<typename Cond, typename LHS, typename RHS>
    629 inline SelectClass_match<Cond, LHS, RHS>
    630 m_Select(const Cond &C, const LHS &L, const RHS &R) {
    631   return SelectClass_match<Cond, LHS, RHS>(C, L, R);
    632 }
    633 
    634 /// m_SelectCst - This matches a select of two constants, e.g.:
    635 ///    m_SelectCst<-1, 0>(m_Value(V))
    636 template<int64_t L, int64_t R, typename Cond>
    637 inline SelectClass_match<Cond, constantint_match<L>, constantint_match<R> >
    638 m_SelectCst(const Cond &C) {
    639   return m_Select(C, m_ConstantInt<L>(), m_ConstantInt<R>());
    640 }
    641 
    642 
    643 //===----------------------------------------------------------------------===//
    644 // Matchers for CastInst classes
    645 //
    646 
    647 template<typename Op_t, unsigned Opcode>
    648 struct CastClass_match {
    649   Op_t Op;
    650 
    651   CastClass_match(const Op_t &OpMatch) : Op(OpMatch) {}
    652 
    653   template<typename OpTy>
    654   bool match(OpTy *V) {
    655     if (Operator *O = dyn_cast<Operator>(V))
    656       return O->getOpcode() == Opcode && Op.match(O->getOperand(0));
    657     return false;
    658   }
    659 };
    660 
    661 /// m_BitCast
    662 template<typename OpTy>
    663 inline CastClass_match<OpTy, Instruction::BitCast>
    664 m_BitCast(const OpTy &Op) {
    665   return CastClass_match<OpTy, Instruction::BitCast>(Op);
    666 }
    667 
    668 /// m_PtrToInt
    669 template<typename OpTy>
    670 inline CastClass_match<OpTy, Instruction::PtrToInt>
    671 m_PtrToInt(const OpTy &Op) {
    672   return CastClass_match<OpTy, Instruction::PtrToInt>(Op);
    673 }
    674 
    675 /// m_Trunc
    676 template<typename OpTy>
    677 inline CastClass_match<OpTy, Instruction::Trunc>
    678 m_Trunc(const OpTy &Op) {
    679   return CastClass_match<OpTy, Instruction::Trunc>(Op);
    680 }
    681 
    682 /// m_SExt
    683 template<typename OpTy>
    684 inline CastClass_match<OpTy, Instruction::SExt>
    685 m_SExt(const OpTy &Op) {
    686   return CastClass_match<OpTy, Instruction::SExt>(Op);
    687 }
    688 
    689 /// m_ZExt
    690 template<typename OpTy>
    691 inline CastClass_match<OpTy, Instruction::ZExt>
    692 m_ZExt(const OpTy &Op) {
    693   return CastClass_match<OpTy, Instruction::ZExt>(Op);
    694 }
    695 
    696 
    697 //===----------------------------------------------------------------------===//
    698 // Matchers for unary operators
    699 //
    700 
    701 template<typename LHS_t>
    702 struct not_match {
    703   LHS_t L;
    704 
    705   not_match(const LHS_t &LHS) : L(LHS) {}
    706 
    707   template<typename OpTy>
    708   bool match(OpTy *V) {
    709     if (Operator *O = dyn_cast<Operator>(V))
    710       if (O->getOpcode() == Instruction::Xor)
    711         return matchIfNot(O->getOperand(0), O->getOperand(1));
    712     return false;
    713   }
    714 private:
    715   bool matchIfNot(Value *LHS, Value *RHS) {
    716     return (isa<ConstantInt>(RHS) || isa<ConstantDataVector>(RHS) ||
    717             // FIXME: Remove CV.
    718             isa<ConstantVector>(RHS)) &&
    719            cast<Constant>(RHS)->isAllOnesValue() &&
    720            L.match(LHS);
    721   }
    722 };
    723 
    724 template<typename LHS>
    725 inline not_match<LHS> m_Not(const LHS &L) { return L; }
    726 
    727 
    728 template<typename LHS_t>
    729 struct neg_match {
    730   LHS_t L;
    731 
    732   neg_match(const LHS_t &LHS) : L(LHS) {}
    733 
    734   template<typename OpTy>
    735   bool match(OpTy *V) {
    736     if (Operator *O = dyn_cast<Operator>(V))
    737       if (O->getOpcode() == Instruction::Sub)
    738         return matchIfNeg(O->getOperand(0), O->getOperand(1));
    739     return false;
    740   }
    741 private:
    742   bool matchIfNeg(Value *LHS, Value *RHS) {
    743     return ((isa<ConstantInt>(LHS) && cast<ConstantInt>(LHS)->isZero()) ||
    744             isa<ConstantAggregateZero>(LHS)) &&
    745            L.match(RHS);
    746   }
    747 };
    748 
    749 /// m_Neg - Match an integer negate.
    750 template<typename LHS>
    751 inline neg_match<LHS> m_Neg(const LHS &L) { return L; }
    752 
    753 
    754 template<typename LHS_t>
    755 struct fneg_match {
    756   LHS_t L;
    757 
    758   fneg_match(const LHS_t &LHS) : L(LHS) {}
    759 
    760   template<typename OpTy>
    761   bool match(OpTy *V) {
    762     if (Operator *O = dyn_cast<Operator>(V))
    763       if (O->getOpcode() == Instruction::FSub)
    764         return matchIfFNeg(O->getOperand(0), O->getOperand(1));
    765     return false;
    766   }
    767 private:
    768   bool matchIfFNeg(Value *LHS, Value *RHS) {
    769     if (ConstantFP *C = dyn_cast<ConstantFP>(LHS))
    770       return C->isNegativeZeroValue() && L.match(RHS);
    771     return false;
    772   }
    773 };
    774 
    775 /// m_FNeg - Match a floating point negate.
    776 template<typename LHS>
    777 inline fneg_match<LHS> m_FNeg(const LHS &L) { return L; }
    778 
    779 
    780 //===----------------------------------------------------------------------===//
    781 // Matchers for control flow.
    782 //
    783 
    784 struct br_match {
    785   BasicBlock *&Succ;
    786   br_match(BasicBlock *&Succ)
    787     : Succ(Succ) {
    788   }
    789 
    790   template<typename OpTy>
    791   bool match(OpTy *V) {
    792     if (BranchInst *BI = dyn_cast<BranchInst>(V))
    793       if (BI->isUnconditional()) {
    794         Succ = BI->getSuccessor(0);
    795         return true;
    796       }
    797     return false;
    798   }
    799 };
    800 
    801 inline br_match m_UnconditionalBr(BasicBlock *&Succ) { return br_match(Succ); }
    802 
    803 template<typename Cond_t>
    804 struct brc_match {
    805   Cond_t Cond;
    806   BasicBlock *&T, *&F;
    807   brc_match(const Cond_t &C, BasicBlock *&t, BasicBlock *&f)
    808     : Cond(C), T(t), F(f) {
    809   }
    810 
    811   template<typename OpTy>
    812   bool match(OpTy *V) {
    813     if (BranchInst *BI = dyn_cast<BranchInst>(V))
    814       if (BI->isConditional() && Cond.match(BI->getCondition())) {
    815         T = BI->getSuccessor(0);
    816         F = BI->getSuccessor(1);
    817         return true;
    818       }
    819     return false;
    820   }
    821 };
    822 
    823 template<typename Cond_t>
    824 inline brc_match<Cond_t> m_Br(const Cond_t &C, BasicBlock *&T, BasicBlock *&F) {
    825   return brc_match<Cond_t>(C, T, F);
    826 }
    827 
    828 
    829 //===----------------------------------------------------------------------===//
    830 // Matchers for max/min idioms, eg: "select (sgt x, y), x, y" -> smax(x,y).
    831 //
    832 
    833 template<typename LHS_t, typename RHS_t, typename Pred_t>
    834 struct MaxMin_match {
    835   LHS_t L;
    836   RHS_t R;
    837 
    838   MaxMin_match(const LHS_t &LHS, const RHS_t &RHS)
    839     : L(LHS), R(RHS) {}
    840 
    841   template<typename OpTy>
    842   bool match(OpTy *V) {
    843     // Look for "(x pred y) ? x : y" or "(x pred y) ? y : x".
    844     SelectInst *SI = dyn_cast<SelectInst>(V);
    845     if (!SI)
    846       return false;
    847     ICmpInst *Cmp = dyn_cast<ICmpInst>(SI->getCondition());
    848     if (!Cmp)
    849       return false;
    850     // At this point we have a select conditioned on a comparison.  Check that
    851     // it is the values returned by the select that are being compared.
    852     Value *TrueVal = SI->getTrueValue();
    853     Value *FalseVal = SI->getFalseValue();
    854     Value *LHS = Cmp->getOperand(0);
    855     Value *RHS = Cmp->getOperand(1);
    856     if ((TrueVal != LHS || FalseVal != RHS) &&
    857         (TrueVal != RHS || FalseVal != LHS))
    858       return false;
    859     ICmpInst::Predicate Pred = LHS == TrueVal ?
    860       Cmp->getPredicate() : Cmp->getSwappedPredicate();
    861     // Does "(x pred y) ? x : y" represent the desired max/min operation?
    862     if (!Pred_t::match(Pred))
    863       return false;
    864     // It does!  Bind the operands.
    865     return L.match(LHS) && R.match(RHS);
    866   }
    867 };
    868 
    869 /// smax_pred_ty - Helper class for identifying signed max predicates.
    870 struct smax_pred_ty {
    871   static bool match(ICmpInst::Predicate Pred) {
    872     return Pred == CmpInst::ICMP_SGT || Pred == CmpInst::ICMP_SGE;
    873   }
    874 };
    875 
    876 /// smin_pred_ty - Helper class for identifying signed min predicates.
    877 struct smin_pred_ty {
    878   static bool match(ICmpInst::Predicate Pred) {
    879     return Pred == CmpInst::ICMP_SLT || Pred == CmpInst::ICMP_SLE;
    880   }
    881 };
    882 
    883 /// umax_pred_ty - Helper class for identifying unsigned max predicates.
    884 struct umax_pred_ty {
    885   static bool match(ICmpInst::Predicate Pred) {
    886     return Pred == CmpInst::ICMP_UGT || Pred == CmpInst::ICMP_UGE;
    887   }
    888 };
    889 
    890 /// umin_pred_ty - Helper class for identifying unsigned min predicates.
    891 struct umin_pred_ty {
    892   static bool match(ICmpInst::Predicate Pred) {
    893     return Pred == CmpInst::ICMP_ULT || Pred == CmpInst::ICMP_ULE;
    894   }
    895 };
    896 
    897 template<typename LHS, typename RHS>
    898 inline MaxMin_match<LHS, RHS, smax_pred_ty>
    899 m_SMax(const LHS &L, const RHS &R) {
    900   return MaxMin_match<LHS, RHS, smax_pred_ty>(L, R);
    901 }
    902 
    903 template<typename LHS, typename RHS>
    904 inline MaxMin_match<LHS, RHS, smin_pred_ty>
    905 m_SMin(const LHS &L, const RHS &R) {
    906   return MaxMin_match<LHS, RHS, smin_pred_ty>(L, R);
    907 }
    908 
    909 template<typename LHS, typename RHS>
    910 inline MaxMin_match<LHS, RHS, umax_pred_ty>
    911 m_UMax(const LHS &L, const RHS &R) {
    912   return MaxMin_match<LHS, RHS, umax_pred_ty>(L, R);
    913 }
    914 
    915 template<typename LHS, typename RHS>
    916 inline MaxMin_match<LHS, RHS, umin_pred_ty>
    917 m_UMin(const LHS &L, const RHS &R) {
    918   return MaxMin_match<LHS, RHS, umin_pred_ty>(L, R);
    919 }
    920 
    921 template<typename Opnd_t>
    922 struct Argument_match {
    923   unsigned OpI;
    924   Opnd_t Val;
    925   Argument_match(unsigned OpIdx, const Opnd_t &V) : OpI(OpIdx), Val(V) { }
    926 
    927   template<typename OpTy>
    928   bool match(OpTy *V) {
    929     CallSite CS(V);
    930     return CS.isCall() && Val.match(CS.getArgument(OpI));
    931   }
    932 };
    933 
    934 /// Match an argument
    935 template<unsigned OpI, typename Opnd_t>
    936 inline Argument_match<Opnd_t> m_Argument(const Opnd_t &Op) {
    937   return Argument_match<Opnd_t>(OpI, Op);
    938 }
    939 
    940 /// Intrinsic matchers.
    941 struct IntrinsicID_match {
    942   unsigned ID;
    943   IntrinsicID_match(unsigned IntrID) : ID(IntrID) { }
    944 
    945   template<typename OpTy>
    946   bool match(OpTy *V) {
    947     IntrinsicInst *II = dyn_cast<IntrinsicInst>(V);
    948     return II && II->getIntrinsicID() == ID;
    949   }
    950 };
    951 
    952 /// Intrinsic matches are combinations of ID matchers, and argument
    953 /// matchers. Higher arity matcher are defined recursively in terms of and-ing
    954 /// them with lower arity matchers. Here's some convenient typedefs for up to
    955 /// several arguments, and more can be added as needed
    956 template <typename T0 = void, typename T1 = void, typename T2 = void,
    957           typename T3 = void, typename T4 = void, typename T5 = void,
    958           typename T6 = void, typename T7 = void, typename T8 = void,
    959           typename T9 = void, typename T10 = void> struct m_Intrinsic_Ty;
    960 template <typename T0>
    961 struct m_Intrinsic_Ty<T0> {
    962   typedef match_combine_and<IntrinsicID_match, Argument_match<T0> > Ty;
    963 };
    964 template <typename T0, typename T1>
    965 struct m_Intrinsic_Ty<T0, T1> {
    966   typedef match_combine_and<typename m_Intrinsic_Ty<T0>::Ty,
    967                             Argument_match<T1> > Ty;
    968 };
    969 template <typename T0, typename T1, typename T2>
    970 struct m_Intrinsic_Ty<T0, T1, T2> {
    971   typedef match_combine_and<typename m_Intrinsic_Ty<T0, T1>::Ty,
    972                             Argument_match<T2> > Ty;
    973 };
    974 template <typename T0, typename T1, typename T2, typename T3>
    975 struct m_Intrinsic_Ty<T0, T1, T2, T3> {
    976   typedef match_combine_and<typename m_Intrinsic_Ty<T0, T1, T2>::Ty,
    977                             Argument_match<T3> > Ty;
    978 };
    979 
    980 /// Match intrinsic calls like this:
    981 ///   m_Intrinsic<Intrinsic::fabs>(m_Value(X))
    982 template <unsigned IntrID>
    983 inline IntrinsicID_match
    984 m_Intrinsic() { return IntrinsicID_match(IntrID); }
    985 
    986 template<unsigned IntrID, typename T0>
    987 inline typename m_Intrinsic_Ty<T0>::Ty
    988 m_Intrinsic(const T0 &Op0) {
    989   return m_CombineAnd(m_Intrinsic<IntrID>(), m_Argument<0>(Op0));
    990 }
    991 
    992 template<unsigned IntrID, typename T0, typename T1>
    993 inline typename m_Intrinsic_Ty<T0, T1>::Ty
    994 m_Intrinsic(const T0 &Op0, const T1 &Op1) {
    995   return m_CombineAnd(m_Intrinsic<IntrID>(Op0), m_Argument<1>(Op1));
    996 }
    997 
    998 template<unsigned IntrID, typename T0, typename T1, typename T2>
    999 inline typename m_Intrinsic_Ty<T0, T1, T2>::Ty
   1000 m_Intrinsic(const T0 &Op0, const T1 &Op1, const T2 &Op2) {
   1001   return m_CombineAnd(m_Intrinsic<IntrID>(Op0, Op1), m_Argument<2>(Op2));
   1002 }
   1003 
   1004 template<unsigned IntrID, typename T0, typename T1, typename T2, typename T3>
   1005 inline typename m_Intrinsic_Ty<T0, T1, T2, T3>::Ty
   1006 m_Intrinsic(const T0 &Op0, const T1 &Op1, const T2 &Op2, const T3 &Op3) {
   1007   return m_CombineAnd(m_Intrinsic<IntrID>(Op0, Op1, Op2), m_Argument<3>(Op3));
   1008 }
   1009 
   1010 // Helper intrinsic matching specializations
   1011 template<typename Opnd0>
   1012 inline typename m_Intrinsic_Ty<Opnd0>::Ty
   1013 m_BSwap(const Opnd0 &Op0) {
   1014   return m_Intrinsic<Intrinsic::bswap>(Op0);
   1015 }
   1016 
   1017 } // end namespace PatternMatch
   1018 } // end namespace llvm
   1019 
   1020 #endif
   1021