package org.jruby.ir.passes;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.jruby.ir.IRClosure;
import org.jruby.ir.IRScope;
import org.jruby.ir.dataflow.analyses.LoadLocalVarPlacementProblem;
import org.jruby.ir.dataflow.analyses.StoreLocalVarPlacementProblem;
import org.jruby.ir.instructions.Instr;
import org.jruby.ir.operands.Operand;
import org.jruby.ir.representations.BasicBlock;
public class AddLocalVarLoadStoreInstructions extends CompilerPass {
public String getLabel() {
return "Add Local Variable Load/Store Instructions";
}
public static List<Class<? extends CompilerPass>> DEPENDENCIES = new ArrayList<Class<? extends CompilerPass>>() {{
add(LiveVariableAnalysis.class);
}};
@Override
public List<Class<? extends CompilerPass>> getDependencies() {
return DEPENDENCIES;
}
public Object execute(IRScope s, Object... data) {
// SSS FIXME: In ancient times, I had this check that wrapped the code below.
// Still useful?
//
// if (s.requiresBinding()) {
// }
// 1. Figure out required stores
// 2. Add stores
// 3. Figure out required loads
// 4. Add loads
//
// Order is important since loads in 3. depend on stores in 2.
StoreLocalVarPlacementProblem slvp = new StoreLocalVarPlacementProblem();
slvp.setup(s);
slvp.compute_MOP_Solution();
// Add stores, assigning an equivalent tmp-var for each local var
Map<Operand, Operand> varRenameMap = new HashMap<Operand, Operand>();
slvp.addStores(varRenameMap);
// Once stores have been added, figure out required loads
LoadLocalVarPlacementProblem llvp = new LoadLocalVarPlacementProblem();
llvp.setup(s);
llvp.compute_MOP_Solution();
// Add loads,
llvp.addLoads(varRenameMap);
// Rename all local var uses with their tmp-var stand-ins
for (BasicBlock b: s.getCFG().getBasicBlocks()) {
for (Instr i: b.getInstrs()) i.renameVars(varRenameMap);
}
// Run on all nested closures.
// In the current implementation, nested scopes are processed independently (unlike Live Variable Analysis)
for (IRClosure c: s.getClosures()) execute(c);
s.setDataFlowSolution(StoreLocalVarPlacementProblem.NAME, slvp);
return slvp;
}
@Override
public Object previouslyRun(IRScope scope) {
return scope.getDataFlowSolution(StoreLocalVarPlacementProblem.NAME);
}
@Override
public void invalidate(IRScope scope) {
scope.setDataFlowSolution(StoreLocalVarPlacementProblem.NAME, null);
}
}