+void RegAllocPBQP::initializeGraph(PBQPRAGraph &G) {
+ MachineFunction &MF = G.getMetadata().MF;
+
+ LiveIntervals &LIS = G.getMetadata().LIS;
+ const MachineRegisterInfo &MRI = G.getMetadata().MF.getRegInfo();
+ const TargetRegisterInfo &TRI =
+ *G.getMetadata().MF.getTarget().getSubtargetImpl()->getRegisterInfo();
+
+ for (auto VReg : VRegsToAlloc) {
+ const TargetRegisterClass *TRC = MRI.getRegClass(VReg);
+ LiveInterval &VRegLI = LIS.getInterval(VReg);
+
+ // Record any overlaps with regmask operands.
+ BitVector RegMaskOverlaps;
+ LIS.checkRegMaskInterference(VRegLI, RegMaskOverlaps);
+
+ // Compute an initial allowed set for the current vreg.
+ std::vector<unsigned> VRegAllowed;
+ ArrayRef<MCPhysReg> RawPRegOrder = TRC->getRawAllocationOrder(MF);
+ for (unsigned I = 0; I != RawPRegOrder.size(); ++I) {
+ unsigned PReg = RawPRegOrder[I];
+ if (MRI.isReserved(PReg))
+ continue;
+
+ // vregLI crosses a regmask operand that clobbers preg.
+ if (!RegMaskOverlaps.empty() && !RegMaskOverlaps.test(PReg))
+ continue;
+
+ // vregLI overlaps fixed regunit interference.
+ bool Interference = false;
+ for (MCRegUnitIterator Units(PReg, &TRI); Units.isValid(); ++Units) {
+ if (VRegLI.overlaps(LIS.getRegUnit(*Units))) {
+ Interference = true;
+ break;
+ }
+ }
+ if (Interference)
+ continue;
+
+ // preg is usable for this virtual register.
+ VRegAllowed.push_back(PReg);
+ }
+
+ PBQPRAGraph::RawVector NodeCosts(VRegAllowed.size() + 1, 0);
+ PBQPRAGraph::NodeId NId = G.addNode(std::move(NodeCosts));
+ G.getNodeMetadata(NId).setVReg(VReg);
+ G.getNodeMetadata(NId).setAllowedRegs(
+ G.getMetadata().getAllowedRegs(std::move(VRegAllowed)));
+ G.getMetadata().setNodeIdForVReg(VReg, NId);
+ }
+}
+
+bool RegAllocPBQP::mapPBQPToRegAlloc(const PBQPRAGraph &G,
+ const PBQP::Solution &Solution,
+ VirtRegMap &VRM,
+ Spiller &VRegSpiller) {
+ MachineFunction &MF = G.getMetadata().MF;
+ LiveIntervals &LIS = G.getMetadata().LIS;
+ const TargetRegisterInfo &TRI =
+ *MF.getTarget().getSubtargetImpl()->getRegisterInfo();
+ (void)TRI;
+