private boolean isExceptionHandler(Incoming incoming) {
return incoming
.getSource()
.getTryCatchJoints()
.stream()
.anyMatch(joint -> joint.getReceiver() == incoming.getValue());
}
private void insertCopy(Incoming incoming, Map<BasicBlock, BasicBlock> blockMap) {
final Phi phi = incoming.getPhi();
Program program = phi.getBasicBlock().getProgram();
AssignInstruction copyInstruction = new AssignInstruction();
Variable firstCopy = program.createVariable();
copyInstruction.setReceiver(firstCopy);
copyInstruction.setAssignee(incoming.getValue());
BasicBlock source = blockMap.get(incoming.getSource());
if (source == null) {
source = incoming.getSource();
} else {
incoming.setSource(source);
}
if (!(incoming.getSource().getLastInstruction() instanceof JumpInstruction)) {
final BasicBlock copyBlock = program.createBasicBlock();
JumpInstruction jumpInstruction = new JumpInstruction();
jumpInstruction.setTarget(phi.getBasicBlock());
copyBlock.getInstructions().add(jumpInstruction);
incoming
.getSource()
.getLastInstruction()
.acceptVisitor(
new BasicBlockMapper(
block -> block == phi.getBasicBlock().getIndex() ? copyBlock.getIndex() : block));
blockMap.put(source, copyBlock);
incoming.setSource(copyBlock);
source = copyBlock;
}
source.getInstructions().add(source.getInstructions().size() - 1, copyInstruction);
incoming.setValue(copyInstruction.getReceiver());
}
private DisjointSet buildPhiCongruenceClasses(Program program) {
DisjointSet classes = new DisjointSet();
for (int i = 0; i < program.variableCount(); ++i) {
classes.create();
}
for (int i = 0; i < program.basicBlockCount(); ++i) {
BasicBlock block = program.basicBlockAt(i);
for (Phi phi : block.getPhis()) {
for (Incoming incoming : phi.getIncomings()) {
classes.union(phi.getReceiver().getIndex(), incoming.getValue().getIndex());
}
}
for (TryCatchJoint joint : block.getTryCatchJoints()) {
for (Variable sourceVar : joint.getSourceVariables()) {
classes.union(sourceVar.getIndex(), joint.getReceiver().getIndex());
}
}
}
return classes;
}