--- /dev/null
+//===-- RegAllocPBQP.h ------------------------------------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the PBQPBuilder interface, for classes which build PBQP
+// instances to represent register allocation problems, and the RegAllocPBQP
+// interface.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_PBQPRACONSTRAINT_H
+#define LLVM_CODEGEN_PBQPRACONSTRAINT_H
+
+#include <memory>
+#include <vector>
+
+namespace llvm {
+namespace PBQP {
+namespace RegAlloc {
+// Forward declare PBQP graph class.
+class PBQPRAGraph;
+}
+}
+
+class LiveIntervals;
+class MachineBlockFrequencyInfo;
+class MachineFunction;
+class TargetRegisterInfo;
+
+typedef PBQP::RegAlloc::PBQPRAGraph PBQPRAGraph;
+
+/// @brief Abstract base for classes implementing PBQP register allocation
+/// constraints (e.g. Spill-costs, interference, coalescing).
+class PBQPRAConstraint {
+public:
+ virtual ~PBQPRAConstraint() = 0;
+ virtual void apply(PBQPRAGraph &G) = 0;
+private:
+ virtual void anchor();
+};
+
+/// @brief PBQP register allocation constraint composer.
+///
+/// Constraints added to this list will be applied, in the order that they are
+/// added, to the PBQP graph.
+class PBQPRAConstraintList : public PBQPRAConstraint {
+public:
+ void apply(PBQPRAGraph &G) override {
+ for (auto &C : Constraints)
+ C->apply(G);
+ }
+
+ void addConstraint(std::unique_ptr<PBQPRAConstraint> C) {
+ if (C)
+ Constraints.push_back(std::move(C));
+ }
+private:
+ std::vector<std::unique_ptr<PBQPRAConstraint>> Constraints;
+ virtual void anchor();
+};
+
+}
+
+#endif /* LLVM_CODEGEN_PBQPRACONSTRAINT_H */
--- /dev/null
+//===-- AArch64PBQPRegAlloc.h - AArch64 specific PBQP constraints -------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TARGET_AARCH64_AARCH64PBQPREGALOC_H
+#define LLVM_LIB_TARGET_AARCH64_AARCH64PBQPREGALOC_H
+
+#include "llvm/ADT/SetVector.h"
+#include "llvm/CodeGen/PBQPRAConstraint.h"
+
+namespace llvm {
+
+class A57PBQPConstraints : public PBQPRAConstraint {
+public:
+
+ // Add A57 specific constraints to the PBQP graph.
+ void apply(PBQPRAGraph &G) override;
+
+private:
+ SmallSetVector<unsigned, 32> Chains;
+
+ // Add the accumulator chaining constraint, inside the chain, i.e. so that
+ // parity(Rd) == parity(Ra).
+ // \return true if a constraint was added
+ bool addIntraChainConstraint(PBQPRAGraph &G, unsigned Rd, unsigned Ra);
+
+ // Add constraints between existing chains
+ void addInterChainConstraint(PBQPRAGraph &G, unsigned Rd, unsigned Ra);
+};
+
+}
+
+#endif // LLVM_LIB_TARGET_AARCH64_AARCH64PBQPREGALOC_H