Reg.java

package elw.dp.mips;

import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;

public enum Reg {
    zero, at, v0, v1,
    a0, a1, a2, a3,

    t0, t1, t2, t3,
    t4, t5, t6, t7,

    s0, s1, s2, s3,
    s4, s5, s6, s7,

    t8, t9, k0, k1,
    gp, sp, fp, ra,

    pc, hi, lo; //  those are extended, usages should be cut off by validations

    public final static List<Reg> publicRegs = Arrays.asList(zero, v0, v1, a0, a1, a2, a3, t0, t1, t2, t3, t4, t5, t6, t7, s0, s1, s2, s3, s4, s5, s6, s7, t8, t9, sp, ra, pc);
    public final static List<Reg> roRegs = Arrays.asList(zero);
    public final static List<Reg> autoRegs = Arrays.asList(pc, sp, ra);
    public final static List<Reg> tempRegs = Arrays.asList(t0, t1, t2, t3, t4, t5, t6, t7, t8, t9, pc, hi, lo);

    private static final Map<String, Reg> byName = new TreeMap<String, Reg>();

    private static TreeMap<String, Reg> createByNameMap() {
        final TreeMap<String, Reg> byNameMap = new TreeMap<String, Reg>();

        for (Reg reg : values()) {
            byName.put(reg.toString().toLowerCase(), reg);
        }

        return byNameMap;
    }

    public synchronized static Map<String, Reg> getByName() {
        if (byName.isEmpty()) {
            byName.putAll(createByNameMap());
        }

        return byName;
    }

    public static Reg[] values(int[] regOrdinals) {
        final Reg[] regs = new Reg[regOrdinals.length];

        for (int i = 0; i < regOrdinals.length; i++) {
            regs[i] = values()[regOrdinals[i]];
        }

        return regs;
    }
}