public void clustering(List<Instruction> instList) {
// for all phi instructions "x = phi(y1,y2)"
for (Instruction inst : instList) {
if (inst.getOperator() == Instruction.phi) {
// cluster = {x},
Cluster phiCluster = this.findCluster(VariableManager.getSSAByVersion(inst.getId()));
if (phiCluster != null) {
this.mergeCluster(phiCluster, inst.getOperand1());
this.mergeCluster(phiCluster, inst.getOperand2());
}
}
}
this.updateInterferenceGraph();
}
private Set<SSA> buildIGFromBlock(BasicBlock curBB, Set<SSA> live) {
List<Instruction> instList = curBB.getInstructions();
for (int i = instList.size() - 1; i >= 0; i--) {
Instruction inst = instList.get(i);
// ignore phi function
if (inst.getOperator() == Instruction.phi) {
return live;
}
if (inst.getOperator() == Instruction.subroutine) {
live = this.buildIGRecursive(inst.getOperand2().block, live);
continue;
}
List<SSA> results = VariableManager.getSSAsByVersion(inst.getId());
// live = live - {i}
live.removeAll(results);
live.remove(null);
// for all x belong to live do
for (SSA result : results) {
Cluster resultCluster = this.getCluster(result);
for (SSA x : live) {
Cluster xCluster = this.getCluster(x);
// add edge i <-> x
xCluster.connectWith(resultCluster);
}
}
// live = live + {j, k}
if (inst.getOperand1() != null) {
SSA j = inst.getOperand1().ssa;
if (j != null) {
live.add(j);
}
}
if (inst.getOperand2() != null) {
SSA k = inst.getOperand2().ssa;
if (k != null) {
live.add(k);
}
}
}
return live;
}