llvm/utils/TableGen/GlobalISel/GIMatchDagEdge.h

   1 //===- GIMatchDagEdge.h - Represent a shared operand list for nodes -------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef LLVM_UTILS_TABLEGEN_GIMATCHDAGEDGE_H
  10 #define LLVM_UTILS_TABLEGEN_GIMATCHDAGEDGE_H
  11
  12 #include "llvm/ADT/StringRef.h"
  13
  14 namespace llvm {
  15 class raw_ostream;
  16 class GIMatchDagInstr;
  17 class GIMatchDagOperand;
  18
  19 /// Represents an edge that connects two instructions together via a pair of
  20 /// operands. For example:
  21 ///     %a = FOO ...
  22 ///     %0 = BAR %a
  23 ///     %1 = BAZ %a
  24 /// would have two edges for %a like so:
  25 ///     BAR:Op#1 --[a]----> Op#0:FOO
  26 ///                         ^
  27 ///     BAZ:Op#1 --[a]------/
  28 /// Ideally, all edges in the DAG are from a use to a def as this is a many
  29 /// to one edge but edges from defs to uses are supported too.
  30 class GIMatchDagEdge {
  31   /// The name of the edge. For example,
  32   ///     (FOO $a, $b, $c)
  33   ///     (BAR $d, $e, $a)
  34   /// will create an edge named 'a' to connect FOO to BAR. Although the name
  35   /// refers to the edge, the canonical value of 'a' is the operand that defines
  36   /// it.
  37   StringRef Name;
  38   const GIMatchDagInstr *FromMI;
  39   const GIMatchDagOperand *FromMO;
  40   const GIMatchDagInstr *ToMI;
  41   const GIMatchDagOperand *ToMO;
  42
  43 public:
  44   GIMatchDagEdge(StringRef Name, const GIMatchDagInstr *FromMI, const GIMatchDagOperand *FromMO,
  45             const GIMatchDagInstr *ToMI, const GIMatchDagOperand *ToMO)
  46       : Name(Name), FromMI(FromMI), FromMO(FromMO), ToMI(ToMI), ToMO(ToMO) {}
  47
  48   StringRef getName() const { return Name; }
  49   const GIMatchDagInstr *getFromMI() const { return FromMI; }
  50   const GIMatchDagOperand *getFromMO() const { return FromMO; }
  51   const GIMatchDagInstr *getToMI() const { return ToMI; }
  52   const GIMatchDagOperand *getToMO() const { return ToMO; }
  53
  54   /// Flip the direction of the edge.
  55   void reverse();
  56
  57   /// Does this edge run from a def to (one of many) uses?
  58   bool isDefToUse() const;
  59
  60   LLVM_DUMP_METHOD void print(raw_ostream &OS) const;
  61
  62 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
  63   LLVM_DUMP_METHOD void dump() const;
  64 #endif // if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
  65 };
  66
  67 raw_ostream &operator<<(raw_ostream &OS, const GIMatchDagEdge &E);
  68
  69 } // end namespace llvm
  70 #endif // ifndef LLVM_UTILS_TABLEGEN_GIMATCHDAGEDGE_H