mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-25 12:12:47 +01:00
80 lines
3.1 KiB
C++
80 lines
3.1 KiB
C++
//===- DAGDeltaAlgorithm.h - A DAG Minimization Algorithm ------*- C++ -*--===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_ADT_DAGDELTAALGORITHM_H
|
|
#define LLVM_ADT_DAGDELTAALGORITHM_H
|
|
|
|
#include <set>
|
|
#include <utility>
|
|
#include <vector>
|
|
|
|
namespace llvm {
|
|
|
|
/// DAGDeltaAlgorithm - Implements a "delta debugging" algorithm for minimizing
|
|
/// directed acyclic graphs using a predicate function.
|
|
///
|
|
/// The result of the algorithm is a subset of the input change set which is
|
|
/// guaranteed to satisfy the predicate, assuming that the input set did. For
|
|
/// well formed predicates, the result set is guaranteed to be such that
|
|
/// removing any single element not required by the dependencies on the other
|
|
/// elements would falsify the predicate.
|
|
///
|
|
/// The DAG should be used to represent dependencies in the changes which are
|
|
/// likely to hold across the predicate function. That is, for a particular
|
|
/// changeset S and predicate P:
|
|
///
|
|
/// P(S) => P(S union pred(S))
|
|
///
|
|
/// The minization algorithm uses this dependency information to attempt to
|
|
/// eagerly prune large subsets of changes. As with \see DeltaAlgorithm, the DAG
|
|
/// is not required to satisfy this property, but the algorithm will run
|
|
/// substantially fewer tests with appropriate dependencies. \see DeltaAlgorithm
|
|
/// for more information on the properties which the predicate function itself
|
|
/// should satisfy.
|
|
class DAGDeltaAlgorithm {
|
|
virtual void anchor();
|
|
|
|
public:
|
|
using change_ty = unsigned;
|
|
using edge_ty = std::pair<change_ty, change_ty>;
|
|
|
|
// FIXME: Use a decent data structure.
|
|
using changeset_ty = std::set<change_ty>;
|
|
using changesetlist_ty = std::vector<changeset_ty>;
|
|
|
|
public:
|
|
virtual ~DAGDeltaAlgorithm() = default;
|
|
|
|
/// Run - Minimize the DAG formed by the \p Changes vertices and the
|
|
/// \p Dependencies edges by executing \see ExecuteOneTest() on subsets of
|
|
/// changes and returning the smallest set which still satisfies the test
|
|
/// predicate and the input \p Dependencies.
|
|
///
|
|
/// \param Changes The list of changes.
|
|
///
|
|
/// \param Dependencies The list of dependencies amongst changes. For each
|
|
/// (x,y) in \p Dependencies, both x and y must be in \p Changes. The
|
|
/// minimization algorithm guarantees that for each tested changed set S,
|
|
/// \f$ x \in S \f$ implies \f$ y \in S \f$. It is an error to have cyclic
|
|
/// dependencies.
|
|
changeset_ty Run(const changeset_ty &Changes,
|
|
const std::vector<edge_ty> &Dependencies);
|
|
|
|
/// UpdatedSearchState - Callback used when the search state changes.
|
|
virtual void UpdatedSearchState(const changeset_ty &Changes,
|
|
const changesetlist_ty &Sets,
|
|
const changeset_ty &Required) {}
|
|
|
|
/// ExecuteOneTest - Execute a single test predicate on the change set \p S.
|
|
virtual bool ExecuteOneTest(const changeset_ty &S) = 0;
|
|
};
|
|
|
|
} // end namespace llvm
|
|
|
|
#endif // LLVM_ADT_DAGDELTAALGORITHM_H
|