Examples with VarExpr org.mapleir.ir.code.expr.VarExpr used on opensource projects

Example 16 with VarExpr

use of org.mapleir.ir.code.expr.VarExpr in project maple-ir by LLVM-but-worse.

the class ControlFlowGraph method overwrite.

/**
 * Replaces an expression and updates def/use information accordingly.
 * @param parent Statement containing expression to be replaced.
 * @param from Statement to be replaced.
 * @param to Statement to replace old statement with.
 */
public void overwrite(CodeUnit parent, Expr from, Expr to) {
    // remove uses in from
    for (Expr e : from.enumerateWithSelf()) {
        if (e.getOpcode() == Opcode.LOCAL_LOAD) {
            VersionedLocal l = (VersionedLocal) ((VarExpr) e).getLocal();
            locals.uses.get(l).remove(e);
        }
    }
    // add uses in to
    for (Expr e : to.enumerateWithSelf()) {
        if (e.getOpcode() == Opcode.LOCAL_LOAD) {
            VarExpr var = (VarExpr) e;
            locals.uses.get((VersionedLocal) var.getLocal()).add(var);
        }
    }
    parent.overwrite(to, parent.indexOf(from));
}

Example 17 with VarExpr

use of org.mapleir.ir.code.expr.VarExpr in project maple-ir by LLVM-but-worse.

the class ControlFlowGraph method exciseEdge.

/**
 * Properly removes the edge, and cleans up phi uses in fe.dst of phi arguments from fe.src.
 * @param fe Edge to excise phi uses.
 */
public void exciseEdge(FlowEdge<BasicBlock> fe) {
    if (!this.containsEdge(fe.src(), fe))
        throw new IllegalArgumentException("Graph does not contain the specified edge");
    removeEdge(fe.src(), fe);
    for (Stmt stmt : fe.dst()) {
        if (stmt.getOpcode() == PHI_STORE) {
            CopyPhiStmt phs = (CopyPhiStmt) stmt;
            PhiExpr phi = phs.getExpression();
            BasicBlock pred = fe.src();
            VarExpr arg = (VarExpr) phi.getArgument(pred);
            VersionedLocal l = (VersionedLocal) arg.getLocal();
            locals.uses.get(l).remove(arg);
            phi.removeArgument(pred);
        } else {
            return;
        }
    }
}

Example 18 with VarExpr

use of org.mapleir.ir.code.expr.VarExpr in project maple-ir by LLVM-but-worse.

the class SSAGenPass method pruneStatements.

private int pruneStatements() {
    int s = pool.uses.size();
    Iterator<Entry<VersionedLocal, Set<VarExpr>>> it = pool.uses.entrySet().iterator();
    while (it.hasNext()) {
        Entry<VersionedLocal, Set<VarExpr>> e = it.next();
        VersionedLocal vl = e.getKey();
        if (e.getValue().size() == 0) {
            AbstractCopyStmt def = pool.defs.get(vl);
            /* i.e. it has not been shadowed. */
            if (def != null && def.getBlock() != null && prune(def)) {
                if (vl != def.getVariable().getLocal()) {
                    throw new RuntimeException(vl + ", " + def);
                }
                /* use pool remove */
                it.remove();
                pool.defs.remove(vl);
            }
        }
    }
    return s - pool.uses.size();
}

Example 19 with VarExpr

use of org.mapleir.ir.code.expr.VarExpr in project maple-ir by LLVM-but-worse.

the class SSAGenPass method aggregateInitialisers.

private void aggregateInitialisers() {
    for (BasicBlock b : builder.graph.vertices()) {
        for (Stmt stmt : new ArrayList<>(b)) {
            if (stmt.getOpcode() == Opcode.POP) {
                PopStmt pop = (PopStmt) stmt;
                Expr expr = pop.getExpression();
                if (expr.getOpcode() == Opcode.INVOKE) {
                    InvocationExpr invoke = (InvocationExpr) expr;
                    if (invoke.getCallType() == InvocationExpr.CallType.SPECIAL && invoke.getName().equals("<init>")) {
                        Expr inst = invoke.getPhysicalReceiver();
                        if (inst.getOpcode() == Opcode.LOCAL_LOAD) {
                            VarExpr var = (VarExpr) inst;
                            VersionedLocal local = (VersionedLocal) var.getLocal();
                            AbstractCopyStmt def = pool.defs.get(local);
                            Expr rhs = def.getExpression();
                            if (rhs.getOpcode() == Opcode.ALLOC_OBJ) {
                                // replace pop(x.<init>()) with x := new Klass();
                                // remove x := new Klass;
                                // here we are assuming that the new object
                                // can't be used until it is initialised.
                                Expr[] args = invoke.getParameterExprs();
                                // we want to reuse the exprs, so free it first.
                                pop.deleteAt(0);
                                Expr[] newArgs = Arrays.copyOf(args, args.length);
                                for (int i = args.length - 1; i >= 0; i--) {
                                    args[i].unlink();
                                }
                                // remove the old def
                                def.delete();
                                int index = b.indexOf(pop);
                                // add a copy statement before the pop (x = newExpr)
                                InitialisedObjectExpr newExpr = new InitialisedObjectExpr(invoke.getOwner(), invoke.getDesc(), newArgs);
                                CopyVarStmt newCvs = new CopyVarStmt(var, newExpr);
                                pool.defs.put(local, newCvs);
                                pool.uses.get(local).remove(var);
                                b.add(index, newCvs);
                                // remove the pop statement
                                b.remove(pop);
                                // update the latestval constraints
                                LatestValue lval = latest.get(local);
                                if (lval.hasConstraints()) {
                                    /* need to check this out (shouldn't happen) */
                                    System.out.println("Constraints:");
                                    for (Constraint c : lval.getConstraints()) {
                                        System.out.println("  " + c);
                                    }
                                    throw new IllegalStateException(lval.toString());
                                } else {
                                    lval.makeConstraints(newExpr);
                                }
                            }
                        } else if (inst.getOpcode() == Opcode.ALLOC_OBJ) {
                            // replace pop(new Klass.<init>(args)) with pop(new Klass(args))
                            // UninitialisedObjectExpr obj = (UninitialisedObjectExpr) inst;
                            Expr[] args = invoke.getParameterExprs();
                            // we want to reuse the exprs, so free it first.
                            invoke.unlink();
                            for (Expr e : args) {
                                e.unlink();
                            }
                            Expr[] newArgs = Arrays.copyOf(args, args.length);
                            InitialisedObjectExpr newExpr = new InitialisedObjectExpr(invoke.getOwner(), invoke.getDesc(), newArgs);
                            // replace pop contents
                            // no changes to defs or uses
                            pop.setExpression(newExpr);
                        } else {
                            System.err.println(b);
                            System.err.println("Stmt: " + stmt.getDisplayName() + ". " + stmt);
                            System.err.println("Inst: " + inst);
                            System.err.println(builder.graph);
                            throw new RuntimeException("interesting1 " + inst.getClass());
                        }
                    }
                }
            }
        }
    }
}

Example 20 with VarExpr

use of org.mapleir.ir.code.expr.VarExpr in project maple-ir by LLVM-but-worse.

the class SSAGenPass method removeSimpleCopy.

private void removeSimpleCopy(AbstractCopyStmt copy) {
    VarExpr v = (VarExpr) copy.getExpression();
    VersionedLocal vl = (VersionedLocal) v.getLocal();
    copy.delete();
    pool.uses.get(vl).remove(v);
}