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      1 //===- CodeGenDAGPatterns.h - Read DAG patterns from .td file ---*- 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 declares the CodeGenDAGPatterns class, which is used to read and
     11 // represent the patterns present in a .td file for instructions.
     12 //
     13 //===----------------------------------------------------------------------===//
     14 
     15 #ifndef LLVM_UTILS_TABLEGEN_CODEGENDAGPATTERNS_H
     16 #define LLVM_UTILS_TABLEGEN_CODEGENDAGPATTERNS_H
     17 
     18 #include "CodeGenIntrinsics.h"
     19 #include "CodeGenTarget.h"
     20 #include "llvm/ADT/SmallVector.h"
     21 #include "llvm/ADT/StringMap.h"
     22 #include "llvm/Support/ErrorHandling.h"
     23 #include <algorithm>
     24 #include <map>
     25 #include <set>
     26 #include <vector>
     27 
     28 namespace llvm {
     29   class Record;
     30   class Init;
     31   class ListInit;
     32   class DagInit;
     33   class SDNodeInfo;
     34   class TreePattern;
     35   class TreePatternNode;
     36   class CodeGenDAGPatterns;
     37   class ComplexPattern;
     38 
     39 /// EEVT::DAGISelGenValueType - These are some extended forms of
     40 /// MVT::SimpleValueType that we use as lattice values during type inference.
     41 /// The existing MVT iAny, fAny and vAny types suffice to represent
     42 /// arbitrary integer, floating-point, and vector types, so only an unknown
     43 /// value is needed.
     44 namespace EEVT {
     45   /// TypeSet - This is either empty if it's completely unknown, or holds a set
     46   /// of types.  It is used during type inference because register classes can
     47   /// have multiple possible types and we don't know which one they get until
     48   /// type inference is complete.
     49   ///
     50   /// TypeSet can have three states:
     51   ///    Vector is empty: The type is completely unknown, it can be any valid
     52   ///       target type.
     53   ///    Vector has multiple constrained types: (e.g. v4i32 + v4f32) it is one
     54   ///       of those types only.
     55   ///    Vector has one concrete type: The type is completely known.
     56   ///
     57   class TypeSet {
     58     SmallVector<MVT::SimpleValueType, 4> TypeVec;
     59   public:
     60     TypeSet() {}
     61     TypeSet(MVT::SimpleValueType VT, TreePattern &TP);
     62     TypeSet(ArrayRef<MVT::SimpleValueType> VTList);
     63 
     64     bool isCompletelyUnknown() const { return TypeVec.empty(); }
     65 
     66     bool isConcrete() const {
     67       if (TypeVec.size() != 1) return false;
     68       unsigned char T = TypeVec[0]; (void)T;
     69       assert(T < MVT::LAST_VALUETYPE || T == MVT::iPTR || T == MVT::iPTRAny);
     70       return true;
     71     }
     72 
     73     MVT::SimpleValueType getConcrete() const {
     74       assert(isConcrete() && "Type isn't concrete yet");
     75       return (MVT::SimpleValueType)TypeVec[0];
     76     }
     77 
     78     bool isDynamicallyResolved() const {
     79       return getConcrete() == MVT::iPTR || getConcrete() == MVT::iPTRAny;
     80     }
     81 
     82     const SmallVectorImpl<MVT::SimpleValueType> &getTypeList() const {
     83       assert(!TypeVec.empty() && "Not a type list!");
     84       return TypeVec;
     85     }
     86 
     87     bool isVoid() const {
     88       return TypeVec.size() == 1 && TypeVec[0] == MVT::isVoid;
     89     }
     90 
     91     /// hasIntegerTypes - Return true if this TypeSet contains any integer value
     92     /// types.
     93     bool hasIntegerTypes() const;
     94 
     95     /// hasFloatingPointTypes - Return true if this TypeSet contains an fAny or
     96     /// a floating point value type.
     97     bool hasFloatingPointTypes() const;
     98 
     99     /// hasScalarTypes - Return true if this TypeSet contains a scalar value
    100     /// type.
    101     bool hasScalarTypes() const;
    102 
    103     /// hasVectorTypes - Return true if this TypeSet contains a vector value
    104     /// type.
    105     bool hasVectorTypes() const;
    106 
    107     /// getName() - Return this TypeSet as a string.
    108     std::string getName() const;
    109 
    110     /// MergeInTypeInfo - This merges in type information from the specified
    111     /// argument.  If 'this' changes, it returns true.  If the two types are
    112     /// contradictory (e.g. merge f32 into i32) then this flags an error.
    113     bool MergeInTypeInfo(const EEVT::TypeSet &InVT, TreePattern &TP);
    114 
    115     bool MergeInTypeInfo(MVT::SimpleValueType InVT, TreePattern &TP) {
    116       return MergeInTypeInfo(EEVT::TypeSet(InVT, TP), TP);
    117     }
    118 
    119     /// Force this type list to only contain integer types.
    120     bool EnforceInteger(TreePattern &TP);
    121 
    122     /// Force this type list to only contain floating point types.
    123     bool EnforceFloatingPoint(TreePattern &TP);
    124 
    125     /// EnforceScalar - Remove all vector types from this type list.
    126     bool EnforceScalar(TreePattern &TP);
    127 
    128     /// EnforceVector - Remove all non-vector types from this type list.
    129     bool EnforceVector(TreePattern &TP);
    130 
    131     /// EnforceSmallerThan - 'this' must be a smaller VT than Other.  Update
    132     /// this an other based on this information.
    133     bool EnforceSmallerThan(EEVT::TypeSet &Other, TreePattern &TP);
    134 
    135     /// EnforceVectorEltTypeIs - 'this' is now constrained to be a vector type
    136     /// whose element is VT.
    137     bool EnforceVectorEltTypeIs(EEVT::TypeSet &VT, TreePattern &TP);
    138 
    139     /// EnforceVectorEltTypeIs - 'this' is now constrained to be a vector type
    140     /// whose element is VT.
    141     bool EnforceVectorEltTypeIs(MVT::SimpleValueType VT, TreePattern &TP);
    142 
    143     /// EnforceVectorSubVectorTypeIs - 'this' is now constrained to
    144     /// be a vector type VT.
    145     bool EnforceVectorSubVectorTypeIs(EEVT::TypeSet &VT, TreePattern &TP);
    146 
    147     /// EnforceVectorSameNumElts - 'this' is now constrained to
    148     /// be a vector with same num elements as VT.
    149     bool EnforceVectorSameNumElts(EEVT::TypeSet &VT, TreePattern &TP);
    150 
    151     /// EnforceSameSize - 'this' is now constrained to be the same size as VT.
    152     bool EnforceSameSize(EEVT::TypeSet &VT, TreePattern &TP);
    153 
    154     bool operator!=(const TypeSet &RHS) const { return TypeVec != RHS.TypeVec; }
    155     bool operator==(const TypeSet &RHS) const { return TypeVec == RHS.TypeVec; }
    156 
    157   private:
    158     /// FillWithPossibleTypes - Set to all legal types and return true, only
    159     /// valid on completely unknown type sets.  If Pred is non-null, only MVTs
    160     /// that pass the predicate are added.
    161     bool FillWithPossibleTypes(TreePattern &TP,
    162                                bool (*Pred)(MVT::SimpleValueType) = nullptr,
    163                                const char *PredicateName = nullptr);
    164   };
    165 }
    166 
    167 /// Set type used to track multiply used variables in patterns
    168 typedef std::set<std::string> MultipleUseVarSet;
    169 
    170 /// SDTypeConstraint - This is a discriminated union of constraints,
    171 /// corresponding to the SDTypeConstraint tablegen class in Target.td.
    172 struct SDTypeConstraint {
    173   SDTypeConstraint(Record *R);
    174 
    175   unsigned OperandNo;   // The operand # this constraint applies to.
    176   enum {
    177     SDTCisVT, SDTCisPtrTy, SDTCisInt, SDTCisFP, SDTCisVec, SDTCisSameAs,
    178     SDTCisVTSmallerThanOp, SDTCisOpSmallerThanOp, SDTCisEltOfVec,
    179     SDTCisSubVecOfVec, SDTCVecEltisVT, SDTCisSameNumEltsAs, SDTCisSameSizeAs
    180   } ConstraintType;
    181 
    182   union {   // The discriminated union.
    183     struct {
    184       MVT::SimpleValueType VT;
    185     } SDTCisVT_Info;
    186     struct {
    187       unsigned OtherOperandNum;
    188     } SDTCisSameAs_Info;
    189     struct {
    190       unsigned OtherOperandNum;
    191     } SDTCisVTSmallerThanOp_Info;
    192     struct {
    193       unsigned BigOperandNum;
    194     } SDTCisOpSmallerThanOp_Info;
    195     struct {
    196       unsigned OtherOperandNum;
    197     } SDTCisEltOfVec_Info;
    198     struct {
    199       unsigned OtherOperandNum;
    200     } SDTCisSubVecOfVec_Info;
    201     struct {
    202       MVT::SimpleValueType VT;
    203     } SDTCVecEltisVT_Info;
    204     struct {
    205       unsigned OtherOperandNum;
    206     } SDTCisSameNumEltsAs_Info;
    207     struct {
    208       unsigned OtherOperandNum;
    209     } SDTCisSameSizeAs_Info;
    210   } x;
    211 
    212   /// ApplyTypeConstraint - Given a node in a pattern, apply this type
    213   /// constraint to the nodes operands.  This returns true if it makes a
    214   /// change, false otherwise.  If a type contradiction is found, an error
    215   /// is flagged.
    216   bool ApplyTypeConstraint(TreePatternNode *N, const SDNodeInfo &NodeInfo,
    217                            TreePattern &TP) const;
    218 };
    219 
    220 /// SDNodeInfo - One of these records is created for each SDNode instance in
    221 /// the target .td file.  This represents the various dag nodes we will be
    222 /// processing.
    223 class SDNodeInfo {
    224   Record *Def;
    225   std::string EnumName;
    226   std::string SDClassName;
    227   unsigned Properties;
    228   unsigned NumResults;
    229   int NumOperands;
    230   std::vector<SDTypeConstraint> TypeConstraints;
    231 public:
    232   SDNodeInfo(Record *R);  // Parse the specified record.
    233 
    234   unsigned getNumResults() const { return NumResults; }
    235 
    236   /// getNumOperands - This is the number of operands required or -1 if
    237   /// variadic.
    238   int getNumOperands() const { return NumOperands; }
    239   Record *getRecord() const { return Def; }
    240   const std::string &getEnumName() const { return EnumName; }
    241   const std::string &getSDClassName() const { return SDClassName; }
    242 
    243   const std::vector<SDTypeConstraint> &getTypeConstraints() const {
    244     return TypeConstraints;
    245   }
    246 
    247   /// getKnownType - If the type constraints on this node imply a fixed type
    248   /// (e.g. all stores return void, etc), then return it as an
    249   /// MVT::SimpleValueType.  Otherwise, return MVT::Other.
    250   MVT::SimpleValueType getKnownType(unsigned ResNo) const;
    251 
    252   /// hasProperty - Return true if this node has the specified property.
    253   ///
    254   bool hasProperty(enum SDNP Prop) const { return Properties & (1 << Prop); }
    255 
    256   /// ApplyTypeConstraints - Given a node in a pattern, apply the type
    257   /// constraints for this node to the operands of the node.  This returns
    258   /// true if it makes a change, false otherwise.  If a type contradiction is
    259   /// found, an error is flagged.
    260   bool ApplyTypeConstraints(TreePatternNode *N, TreePattern &TP) const {
    261     bool MadeChange = false;
    262     for (unsigned i = 0, e = TypeConstraints.size(); i != e; ++i)
    263       MadeChange |= TypeConstraints[i].ApplyTypeConstraint(N, *this, TP);
    264     return MadeChange;
    265   }
    266 };
    267 
    268 /// TreePredicateFn - This is an abstraction that represents the predicates on
    269 /// a PatFrag node.  This is a simple one-word wrapper around a pointer to
    270 /// provide nice accessors.
    271 class TreePredicateFn {
    272   /// PatFragRec - This is the TreePattern for the PatFrag that we
    273   /// originally came from.
    274   TreePattern *PatFragRec;
    275 public:
    276   /// TreePredicateFn constructor.  Here 'N' is a subclass of PatFrag.
    277   TreePredicateFn(TreePattern *N);
    278 
    279 
    280   TreePattern *getOrigPatFragRecord() const { return PatFragRec; }
    281 
    282   /// isAlwaysTrue - Return true if this is a noop predicate.
    283   bool isAlwaysTrue() const;
    284 
    285   bool isImmediatePattern() const { return !getImmCode().empty(); }
    286 
    287   /// getImmediatePredicateCode - Return the code that evaluates this pattern if
    288   /// this is an immediate predicate.  It is an error to call this on a
    289   /// non-immediate pattern.
    290   std::string getImmediatePredicateCode() const {
    291     std::string Result = getImmCode();
    292     assert(!Result.empty() && "Isn't an immediate pattern!");
    293     return Result;
    294   }
    295 
    296 
    297   bool operator==(const TreePredicateFn &RHS) const {
    298     return PatFragRec == RHS.PatFragRec;
    299   }
    300 
    301   bool operator!=(const TreePredicateFn &RHS) const { return !(*this == RHS); }
    302 
    303   /// Return the name to use in the generated code to reference this, this is
    304   /// "Predicate_foo" if from a pattern fragment "foo".
    305   std::string getFnName() const;
    306 
    307   /// getCodeToRunOnSDNode - Return the code for the function body that
    308   /// evaluates this predicate.  The argument is expected to be in "Node",
    309   /// not N.  This handles casting and conversion to a concrete node type as
    310   /// appropriate.
    311   std::string getCodeToRunOnSDNode() const;
    312 
    313 private:
    314   std::string getPredCode() const;
    315   std::string getImmCode() const;
    316 };
    317 
    318 
    319 /// FIXME: TreePatternNode's can be shared in some cases (due to dag-shaped
    320 /// patterns), and as such should be ref counted.  We currently just leak all
    321 /// TreePatternNode objects!
    322 class TreePatternNode {
    323   /// The type of each node result.  Before and during type inference, each
    324   /// result may be a set of possible types.  After (successful) type inference,
    325   /// each is a single concrete type.
    326   SmallVector<EEVT::TypeSet, 1> Types;
    327 
    328   /// Operator - The Record for the operator if this is an interior node (not
    329   /// a leaf).
    330   Record *Operator;
    331 
    332   /// Val - The init value (e.g. the "GPRC" record, or "7") for a leaf.
    333   ///
    334   Init *Val;
    335 
    336   /// Name - The name given to this node with the :$foo notation.
    337   ///
    338   std::string Name;
    339 
    340   /// PredicateFns - The predicate functions to execute on this node to check
    341   /// for a match.  If this list is empty, no predicate is involved.
    342   std::vector<TreePredicateFn> PredicateFns;
    343 
    344   /// TransformFn - The transformation function to execute on this node before
    345   /// it can be substituted into the resulting instruction on a pattern match.
    346   Record *TransformFn;
    347 
    348   std::vector<TreePatternNode*> Children;
    349 public:
    350   TreePatternNode(Record *Op, const std::vector<TreePatternNode*> &Ch,
    351                   unsigned NumResults)
    352     : Operator(Op), Val(nullptr), TransformFn(nullptr), Children(Ch) {
    353     Types.resize(NumResults);
    354   }
    355   TreePatternNode(Init *val, unsigned NumResults)    // leaf ctor
    356     : Operator(nullptr), Val(val), TransformFn(nullptr) {
    357     Types.resize(NumResults);
    358   }
    359   ~TreePatternNode();
    360 
    361   bool hasName() const { return !Name.empty(); }
    362   const std::string &getName() const { return Name; }
    363   void setName(StringRef N) { Name.assign(N.begin(), N.end()); }
    364 
    365   bool isLeaf() const { return Val != nullptr; }
    366 
    367   // Type accessors.
    368   unsigned getNumTypes() const { return Types.size(); }
    369   MVT::SimpleValueType getType(unsigned ResNo) const {
    370     return Types[ResNo].getConcrete();
    371   }
    372   const SmallVectorImpl<EEVT::TypeSet> &getExtTypes() const { return Types; }
    373   const EEVT::TypeSet &getExtType(unsigned ResNo) const { return Types[ResNo]; }
    374   EEVT::TypeSet &getExtType(unsigned ResNo) { return Types[ResNo]; }
    375   void setType(unsigned ResNo, const EEVT::TypeSet &T) { Types[ResNo] = T; }
    376 
    377   bool hasTypeSet(unsigned ResNo) const {
    378     return Types[ResNo].isConcrete();
    379   }
    380   bool isTypeCompletelyUnknown(unsigned ResNo) const {
    381     return Types[ResNo].isCompletelyUnknown();
    382   }
    383   bool isTypeDynamicallyResolved(unsigned ResNo) const {
    384     return Types[ResNo].isDynamicallyResolved();
    385   }
    386 
    387   Init *getLeafValue() const { assert(isLeaf()); return Val; }
    388   Record *getOperator() const { assert(!isLeaf()); return Operator; }
    389 
    390   unsigned getNumChildren() const { return Children.size(); }
    391   TreePatternNode *getChild(unsigned N) const { return Children[N]; }
    392   void setChild(unsigned i, TreePatternNode *N) {
    393     Children[i] = N;
    394   }
    395 
    396   /// hasChild - Return true if N is any of our children.
    397   bool hasChild(const TreePatternNode *N) const {
    398     for (unsigned i = 0, e = Children.size(); i != e; ++i)
    399       if (Children[i] == N) return true;
    400     return false;
    401   }
    402 
    403   bool hasAnyPredicate() const { return !PredicateFns.empty(); }
    404 
    405   const std::vector<TreePredicateFn> &getPredicateFns() const {
    406     return PredicateFns;
    407   }
    408   void clearPredicateFns() { PredicateFns.clear(); }
    409   void setPredicateFns(const std::vector<TreePredicateFn> &Fns) {
    410     assert(PredicateFns.empty() && "Overwriting non-empty predicate list!");
    411     PredicateFns = Fns;
    412   }
    413   void addPredicateFn(const TreePredicateFn &Fn) {
    414     assert(!Fn.isAlwaysTrue() && "Empty predicate string!");
    415     if (std::find(PredicateFns.begin(), PredicateFns.end(), Fn) ==
    416           PredicateFns.end())
    417       PredicateFns.push_back(Fn);
    418   }
    419 
    420   Record *getTransformFn() const { return TransformFn; }
    421   void setTransformFn(Record *Fn) { TransformFn = Fn; }
    422 
    423   /// getIntrinsicInfo - If this node corresponds to an intrinsic, return the
    424   /// CodeGenIntrinsic information for it, otherwise return a null pointer.
    425   const CodeGenIntrinsic *getIntrinsicInfo(const CodeGenDAGPatterns &CDP) const;
    426 
    427   /// getComplexPatternInfo - If this node corresponds to a ComplexPattern,
    428   /// return the ComplexPattern information, otherwise return null.
    429   const ComplexPattern *
    430   getComplexPatternInfo(const CodeGenDAGPatterns &CGP) const;
    431 
    432   /// Returns the number of MachineInstr operands that would be produced by this
    433   /// node if it mapped directly to an output Instruction's
    434   /// operand. ComplexPattern specifies this explicitly; MIOperandInfo gives it
    435   /// for Operands; otherwise 1.
    436   unsigned getNumMIResults(const CodeGenDAGPatterns &CGP) const;
    437 
    438   /// NodeHasProperty - Return true if this node has the specified property.
    439   bool NodeHasProperty(SDNP Property, const CodeGenDAGPatterns &CGP) const;
    440 
    441   /// TreeHasProperty - Return true if any node in this tree has the specified
    442   /// property.
    443   bool TreeHasProperty(SDNP Property, const CodeGenDAGPatterns &CGP) const;
    444 
    445   /// isCommutativeIntrinsic - Return true if the node is an intrinsic which is
    446   /// marked isCommutative.
    447   bool isCommutativeIntrinsic(const CodeGenDAGPatterns &CDP) const;
    448 
    449   void print(raw_ostream &OS) const;
    450   void dump() const;
    451 
    452 public:   // Higher level manipulation routines.
    453 
    454   /// clone - Return a new copy of this tree.
    455   ///
    456   TreePatternNode *clone() const;
    457 
    458   /// RemoveAllTypes - Recursively strip all the types of this tree.
    459   void RemoveAllTypes();
    460 
    461   /// isIsomorphicTo - Return true if this node is recursively isomorphic to
    462   /// the specified node.  For this comparison, all of the state of the node
    463   /// is considered, except for the assigned name.  Nodes with differing names
    464   /// that are otherwise identical are considered isomorphic.
    465   bool isIsomorphicTo(const TreePatternNode *N,
    466                       const MultipleUseVarSet &DepVars) const;
    467 
    468   /// SubstituteFormalArguments - Replace the formal arguments in this tree
    469   /// with actual values specified by ArgMap.
    470   void SubstituteFormalArguments(std::map<std::string,
    471                                           TreePatternNode*> &ArgMap);
    472 
    473   /// InlinePatternFragments - If this pattern refers to any pattern
    474   /// fragments, inline them into place, giving us a pattern without any
    475   /// PatFrag references.
    476   TreePatternNode *InlinePatternFragments(TreePattern &TP);
    477 
    478   /// ApplyTypeConstraints - Apply all of the type constraints relevant to
    479   /// this node and its children in the tree.  This returns true if it makes a
    480   /// change, false otherwise.  If a type contradiction is found, flag an error.
    481   bool ApplyTypeConstraints(TreePattern &TP, bool NotRegisters);
    482 
    483   /// UpdateNodeType - Set the node type of N to VT if VT contains
    484   /// information.  If N already contains a conflicting type, then flag an
    485   /// error.  This returns true if any information was updated.
    486   ///
    487   bool UpdateNodeType(unsigned ResNo, const EEVT::TypeSet &InTy,
    488                       TreePattern &TP) {
    489     return Types[ResNo].MergeInTypeInfo(InTy, TP);
    490   }
    491 
    492   bool UpdateNodeType(unsigned ResNo, MVT::SimpleValueType InTy,
    493                       TreePattern &TP) {
    494     return Types[ResNo].MergeInTypeInfo(EEVT::TypeSet(InTy, TP), TP);
    495   }
    496 
    497   // Update node type with types inferred from an instruction operand or result
    498   // def from the ins/outs lists.
    499   // Return true if the type changed.
    500   bool UpdateNodeTypeFromInst(unsigned ResNo, Record *Operand, TreePattern &TP);
    501 
    502   /// ContainsUnresolvedType - Return true if this tree contains any
    503   /// unresolved types.
    504   bool ContainsUnresolvedType() const {
    505     for (unsigned i = 0, e = Types.size(); i != e; ++i)
    506       if (!Types[i].isConcrete()) return true;
    507 
    508     for (unsigned i = 0, e = getNumChildren(); i != e; ++i)
    509       if (getChild(i)->ContainsUnresolvedType()) return true;
    510     return false;
    511   }
    512 
    513   /// canPatternMatch - If it is impossible for this pattern to match on this
    514   /// target, fill in Reason and return false.  Otherwise, return true.
    515   bool canPatternMatch(std::string &Reason, const CodeGenDAGPatterns &CDP);
    516 };
    517 
    518 inline raw_ostream &operator<<(raw_ostream &OS, const TreePatternNode &TPN) {
    519   TPN.print(OS);
    520   return OS;
    521 }
    522 
    523 
    524 /// TreePattern - Represent a pattern, used for instructions, pattern
    525 /// fragments, etc.
    526 ///
    527 class TreePattern {
    528   /// Trees - The list of pattern trees which corresponds to this pattern.
    529   /// Note that PatFrag's only have a single tree.
    530   ///
    531   std::vector<TreePatternNode*> Trees;
    532 
    533   /// NamedNodes - This is all of the nodes that have names in the trees in this
    534   /// pattern.
    535   StringMap<SmallVector<TreePatternNode*,1> > NamedNodes;
    536 
    537   /// TheRecord - The actual TableGen record corresponding to this pattern.
    538   ///
    539   Record *TheRecord;
    540 
    541   /// Args - This is a list of all of the arguments to this pattern (for
    542   /// PatFrag patterns), which are the 'node' markers in this pattern.
    543   std::vector<std::string> Args;
    544 
    545   /// CDP - the top-level object coordinating this madness.
    546   ///
    547   CodeGenDAGPatterns &CDP;
    548 
    549   /// isInputPattern - True if this is an input pattern, something to match.
    550   /// False if this is an output pattern, something to emit.
    551   bool isInputPattern;
    552 
    553   /// hasError - True if the currently processed nodes have unresolvable types
    554   /// or other non-fatal errors
    555   bool HasError;
    556 
    557   /// It's important that the usage of operands in ComplexPatterns is
    558   /// consistent: each named operand can be defined by at most one
    559   /// ComplexPattern. This records the ComplexPattern instance and the operand
    560   /// number for each operand encountered in a ComplexPattern to aid in that
    561   /// check.
    562   StringMap<std::pair<Record *, unsigned>> ComplexPatternOperands;
    563 public:
    564 
    565   /// TreePattern constructor - Parse the specified DagInits into the
    566   /// current record.
    567   TreePattern(Record *TheRec, ListInit *RawPat, bool isInput,
    568               CodeGenDAGPatterns &ise);
    569   TreePattern(Record *TheRec, DagInit *Pat, bool isInput,
    570               CodeGenDAGPatterns &ise);
    571   TreePattern(Record *TheRec, TreePatternNode *Pat, bool isInput,
    572               CodeGenDAGPatterns &ise);
    573 
    574   /// getTrees - Return the tree patterns which corresponds to this pattern.
    575   ///
    576   const std::vector<TreePatternNode*> &getTrees() const { return Trees; }
    577   unsigned getNumTrees() const { return Trees.size(); }
    578   TreePatternNode *getTree(unsigned i) const { return Trees[i]; }
    579   TreePatternNode *getOnlyTree() const {
    580     assert(Trees.size() == 1 && "Doesn't have exactly one pattern!");
    581     return Trees[0];
    582   }
    583 
    584   const StringMap<SmallVector<TreePatternNode*,1> > &getNamedNodesMap() {
    585     if (NamedNodes.empty())
    586       ComputeNamedNodes();
    587     return NamedNodes;
    588   }
    589 
    590   /// getRecord - Return the actual TableGen record corresponding to this
    591   /// pattern.
    592   ///
    593   Record *getRecord() const { return TheRecord; }
    594 
    595   unsigned getNumArgs() const { return Args.size(); }
    596   const std::string &getArgName(unsigned i) const {
    597     assert(i < Args.size() && "Argument reference out of range!");
    598     return Args[i];
    599   }
    600   std::vector<std::string> &getArgList() { return Args; }
    601 
    602   CodeGenDAGPatterns &getDAGPatterns() const { return CDP; }
    603 
    604   /// InlinePatternFragments - If this pattern refers to any pattern
    605   /// fragments, inline them into place, giving us a pattern without any
    606   /// PatFrag references.
    607   void InlinePatternFragments() {
    608     for (unsigned i = 0, e = Trees.size(); i != e; ++i)
    609       Trees[i] = Trees[i]->InlinePatternFragments(*this);
    610   }
    611 
    612   /// InferAllTypes - Infer/propagate as many types throughout the expression
    613   /// patterns as possible.  Return true if all types are inferred, false
    614   /// otherwise.  Bail out if a type contradiction is found.
    615   bool InferAllTypes(const StringMap<SmallVector<TreePatternNode*,1> >
    616                           *NamedTypes=nullptr);
    617 
    618   /// error - If this is the first error in the current resolution step,
    619   /// print it and set the error flag.  Otherwise, continue silently.
    620   void error(const Twine &Msg);
    621   bool hasError() const {
    622     return HasError;
    623   }
    624   void resetError() {
    625     HasError = false;
    626   }
    627 
    628   void print(raw_ostream &OS) const;
    629   void dump() const;
    630 
    631 private:
    632   TreePatternNode *ParseTreePattern(Init *DI, StringRef OpName);
    633   void ComputeNamedNodes();
    634   void ComputeNamedNodes(TreePatternNode *N);
    635 };
    636 
    637 /// DAGDefaultOperand - One of these is created for each OperandWithDefaultOps
    638 /// that has a set ExecuteAlways / DefaultOps field.
    639 struct DAGDefaultOperand {
    640   std::vector<TreePatternNode*> DefaultOps;
    641 };
    642 
    643 class DAGInstruction {
    644   TreePattern *Pattern;
    645   std::vector<Record*> Results;
    646   std::vector<Record*> Operands;
    647   std::vector<Record*> ImpResults;
    648   TreePatternNode *ResultPattern;
    649 public:
    650   DAGInstruction(TreePattern *TP,
    651                  const std::vector<Record*> &results,
    652                  const std::vector<Record*> &operands,
    653                  const std::vector<Record*> &impresults)
    654     : Pattern(TP), Results(results), Operands(operands),
    655       ImpResults(impresults), ResultPattern(nullptr) {}
    656 
    657   TreePattern *getPattern() const { return Pattern; }
    658   unsigned getNumResults() const { return Results.size(); }
    659   unsigned getNumOperands() const { return Operands.size(); }
    660   unsigned getNumImpResults() const { return ImpResults.size(); }
    661   const std::vector<Record*>& getImpResults() const { return ImpResults; }
    662 
    663   void setResultPattern(TreePatternNode *R) { ResultPattern = R; }
    664 
    665   Record *getResult(unsigned RN) const {
    666     assert(RN < Results.size());
    667     return Results[RN];
    668   }
    669 
    670   Record *getOperand(unsigned ON) const {
    671     assert(ON < Operands.size());
    672     return Operands[ON];
    673   }
    674 
    675   Record *getImpResult(unsigned RN) const {
    676     assert(RN < ImpResults.size());
    677     return ImpResults[RN];
    678   }
    679 
    680   TreePatternNode *getResultPattern() const { return ResultPattern; }
    681 };
    682 
    683 /// PatternToMatch - Used by CodeGenDAGPatterns to keep tab of patterns
    684 /// processed to produce isel.
    685 class PatternToMatch {
    686 public:
    687   PatternToMatch(Record *srcrecord, ListInit *preds,
    688                  TreePatternNode *src, TreePatternNode *dst,
    689                  const std::vector<Record*> &dstregs,
    690                  int complexity, unsigned uid)
    691     : SrcRecord(srcrecord), Predicates(preds), SrcPattern(src), DstPattern(dst),
    692       Dstregs(dstregs), AddedComplexity(complexity), ID(uid) {}
    693 
    694   Record          *SrcRecord;   // Originating Record for the pattern.
    695   ListInit        *Predicates;  // Top level predicate conditions to match.
    696   TreePatternNode *SrcPattern;  // Source pattern to match.
    697   TreePatternNode *DstPattern;  // Resulting pattern.
    698   std::vector<Record*> Dstregs; // Physical register defs being matched.
    699   int              AddedComplexity; // Add to matching pattern complexity.
    700   unsigned         ID;          // Unique ID for the record.
    701 
    702   Record          *getSrcRecord()  const { return SrcRecord; }
    703   ListInit        *getPredicates() const { return Predicates; }
    704   TreePatternNode *getSrcPattern() const { return SrcPattern; }
    705   TreePatternNode *getDstPattern() const { return DstPattern; }
    706   const std::vector<Record*> &getDstRegs() const { return Dstregs; }
    707   int         getAddedComplexity() const { return AddedComplexity; }
    708 
    709   std::string getPredicateCheck() const;
    710 
    711   /// Compute the complexity metric for the input pattern.  This roughly
    712   /// corresponds to the number of nodes that are covered.
    713   int getPatternComplexity(const CodeGenDAGPatterns &CGP) const;
    714 };
    715 
    716 class CodeGenDAGPatterns {
    717   RecordKeeper &Records;
    718   CodeGenTarget Target;
    719   std::vector<CodeGenIntrinsic> Intrinsics;
    720   std::vector<CodeGenIntrinsic> TgtIntrinsics;
    721 
    722   std::map<Record*, SDNodeInfo, LessRecordByID> SDNodes;
    723   std::map<Record*, std::pair<Record*, std::string>, LessRecordByID> SDNodeXForms;
    724   std::map<Record*, ComplexPattern, LessRecordByID> ComplexPatterns;
    725   std::map<Record *, std::unique_ptr<TreePattern>, LessRecordByID>
    726       PatternFragments;
    727   std::map<Record*, DAGDefaultOperand, LessRecordByID> DefaultOperands;
    728   std::map<Record*, DAGInstruction, LessRecordByID> Instructions;
    729 
    730   // Specific SDNode definitions:
    731   Record *intrinsic_void_sdnode;
    732   Record *intrinsic_w_chain_sdnode, *intrinsic_wo_chain_sdnode;
    733 
    734   /// PatternsToMatch - All of the things we are matching on the DAG.  The first
    735   /// value is the pattern to match, the second pattern is the result to
    736   /// emit.
    737   std::vector<PatternToMatch> PatternsToMatch;
    738 public:
    739   CodeGenDAGPatterns(RecordKeeper &R);
    740 
    741   CodeGenTarget &getTargetInfo() { return Target; }
    742   const CodeGenTarget &getTargetInfo() const { return Target; }
    743 
    744   Record *getSDNodeNamed(const std::string &Name) const;
    745 
    746   const SDNodeInfo &getSDNodeInfo(Record *R) const {
    747     assert(SDNodes.count(R) && "Unknown node!");
    748     return SDNodes.find(R)->second;
    749   }
    750 
    751   // Node transformation lookups.
    752   typedef std::pair<Record*, std::string> NodeXForm;
    753   const NodeXForm &getSDNodeTransform(Record *R) const {
    754     assert(SDNodeXForms.count(R) && "Invalid transform!");
    755     return SDNodeXForms.find(R)->second;
    756   }
    757 
    758   typedef std::map<Record*, NodeXForm, LessRecordByID>::const_iterator
    759           nx_iterator;
    760   nx_iterator nx_begin() const { return SDNodeXForms.begin(); }
    761   nx_iterator nx_end() const { return SDNodeXForms.end(); }
    762 
    763 
    764   const ComplexPattern &getComplexPattern(Record *R) const {
    765     assert(ComplexPatterns.count(R) && "Unknown addressing mode!");
    766     return ComplexPatterns.find(R)->second;
    767   }
    768 
    769   const CodeGenIntrinsic &getIntrinsic(Record *R) const {
    770     for (unsigned i = 0, e = Intrinsics.size(); i != e; ++i)
    771       if (Intrinsics[i].TheDef == R) return Intrinsics[i];
    772     for (unsigned i = 0, e = TgtIntrinsics.size(); i != e; ++i)
    773       if (TgtIntrinsics[i].TheDef == R) return TgtIntrinsics[i];
    774     llvm_unreachable("Unknown intrinsic!");
    775   }
    776 
    777   const CodeGenIntrinsic &getIntrinsicInfo(unsigned IID) const {
    778     if (IID-1 < Intrinsics.size())
    779       return Intrinsics[IID-1];
    780     if (IID-Intrinsics.size()-1 < TgtIntrinsics.size())
    781       return TgtIntrinsics[IID-Intrinsics.size()-1];
    782     llvm_unreachable("Bad intrinsic ID!");
    783   }
    784 
    785   unsigned getIntrinsicID(Record *R) const {
    786     for (unsigned i = 0, e = Intrinsics.size(); i != e; ++i)
    787       if (Intrinsics[i].TheDef == R) return i;
    788     for (unsigned i = 0, e = TgtIntrinsics.size(); i != e; ++i)
    789       if (TgtIntrinsics[i].TheDef == R) return i + Intrinsics.size();
    790     llvm_unreachable("Unknown intrinsic!");
    791   }
    792 
    793   const DAGDefaultOperand &getDefaultOperand(Record *R) const {
    794     assert(DefaultOperands.count(R) &&"Isn't an analyzed default operand!");
    795     return DefaultOperands.find(R)->second;
    796   }
    797 
    798   // Pattern Fragment information.
    799   TreePattern *getPatternFragment(Record *R) const {
    800     assert(PatternFragments.count(R) && "Invalid pattern fragment request!");
    801     return PatternFragments.find(R)->second.get();
    802   }
    803   TreePattern *getPatternFragmentIfRead(Record *R) const {
    804     if (!PatternFragments.count(R))
    805       return nullptr;
    806     return PatternFragments.find(R)->second.get();
    807   }
    808 
    809   typedef std::map<Record *, std::unique_ptr<TreePattern>,
    810                    LessRecordByID>::const_iterator pf_iterator;
    811   pf_iterator pf_begin() const { return PatternFragments.begin(); }
    812   pf_iterator pf_end() const { return PatternFragments.end(); }
    813 
    814   // Patterns to match information.
    815   typedef std::vector<PatternToMatch>::const_iterator ptm_iterator;
    816   ptm_iterator ptm_begin() const { return PatternsToMatch.begin(); }
    817   ptm_iterator ptm_end() const { return PatternsToMatch.end(); }
    818 
    819   /// Parse the Pattern for an instruction, and insert the result in DAGInsts.
    820   typedef std::map<Record*, DAGInstruction, LessRecordByID> DAGInstMap;
    821   const DAGInstruction &parseInstructionPattern(
    822       CodeGenInstruction &CGI, ListInit *Pattern,
    823       DAGInstMap &DAGInsts);
    824 
    825   const DAGInstruction &getInstruction(Record *R) const {
    826     assert(Instructions.count(R) && "Unknown instruction!");
    827     return Instructions.find(R)->second;
    828   }
    829 
    830   Record *get_intrinsic_void_sdnode() const {
    831     return intrinsic_void_sdnode;
    832   }
    833   Record *get_intrinsic_w_chain_sdnode() const {
    834     return intrinsic_w_chain_sdnode;
    835   }
    836   Record *get_intrinsic_wo_chain_sdnode() const {
    837     return intrinsic_wo_chain_sdnode;
    838   }
    839 
    840   bool hasTargetIntrinsics() { return !TgtIntrinsics.empty(); }
    841 
    842 private:
    843   void ParseNodeInfo();
    844   void ParseNodeTransforms();
    845   void ParseComplexPatterns();
    846   void ParsePatternFragments(bool OutFrags = false);
    847   void ParseDefaultOperands();
    848   void ParseInstructions();
    849   void ParsePatterns();
    850   void InferInstructionFlags();
    851   void GenerateVariants();
    852   void VerifyInstructionFlags();
    853 
    854   void AddPatternToMatch(TreePattern *Pattern, const PatternToMatch &PTM);
    855   void FindPatternInputsAndOutputs(TreePattern *I, TreePatternNode *Pat,
    856                                    std::map<std::string,
    857                                    TreePatternNode*> &InstInputs,
    858                                    std::map<std::string,
    859                                    TreePatternNode*> &InstResults,
    860                                    std::vector<Record*> &InstImpResults);
    861 };
    862 } // end namespace llvm
    863 
    864 #endif
    865