1//===- llvm/CodeGen/PBQPRAConstraint.h --------------------------*- C++ -*-===//
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// This file defines the PBQPBuilder interface, for classes which build PBQP
10// instances to represent register allocation problems, and the RegAllocPBQP
11// interface.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_CODEGEN_PBQPRACONSTRAINT_H
16#define LLVM_CODEGEN_PBQPRACONSTRAINT_H
17
18#include <algorithm>
19#include <memory>
20#include <vector>
21
22namespace llvm {
23
24namespace PBQP {
25namespace RegAlloc {
26
27// Forward declare PBQP graph class.
28class PBQPRAGraph;
29
30} // end namespace RegAlloc
31} // end namespace PBQP
32
33using PBQPRAGraph = PBQP::RegAlloc::PBQPRAGraph;
34
35/// Abstract base for classes implementing PBQP register allocation
36///        constraints (e.g. Spill-costs, interference, coalescing).
37class PBQPRAConstraint {
38public:
39  virtual ~PBQPRAConstraint() = 0;
40  virtual void apply(PBQPRAGraph &G) = 0;
41
42private:
43  virtual void anchor();
44};
45
46/// PBQP register allocation constraint composer.
47///
48///   Constraints added to this list will be applied, in the order that they are
49/// added, to the PBQP graph.
50class PBQPRAConstraintList : public PBQPRAConstraint {
51public:
52  void apply(PBQPRAGraph &G) override {
53    for (auto &C : Constraints)
54      C->apply(G);
55  }
56
57  void addConstraint(std::unique_ptr<PBQPRAConstraint> C) {
58    if (C)
59      Constraints.push_back(std::move(C));
60  }
61
62private:
63  std::vector<std::unique_ptr<PBQPRAConstraint>> Constraints;
64
65  void anchor() override;
66};
67
68} // end namespace llvm
69
70#endif // LLVM_CODEGEN_PBQPRACONSTRAINT_H
71