com.android.dx.rop.code.RegOps Java Examples

/**
 * Checks to see if the given SSA reg is ever associated with a local
 * local variable. Each SSA reg may be associated with at most one
 * local var.
 *
 * @param spec {@code non-null;} ssa reg
 * @return true if reg is ever associated with a local
 */
public boolean isRegALocal(RegisterSpec spec) {
    SsaInsn defn = getDefinitionForRegister(spec.getReg());

    if (defn == null) {
        // version 0 registers are never used as locals
        return false;
    }

    // Does the definition have a local associated with it?
    if (defn.getLocalAssignment() != null) return true;

    // If not, is there a mark-local insn?
    for (SsaInsn use : getUseListForRegister(spec.getReg())) {
        Insn insn = use.getOriginalRopInsn();

        if (insn != null
                && insn.getOpcode().getOpcode() == RegOps.MARK_LOCAL) {
            return true;
        }
    }

    return false;
}
 

/** {@inheritDoc} */
@Override
public RegisterSpec getLocalAssignment() {
    RegisterSpec assignment;

    if (insn.getOpcode().getOpcode() == RegOps.MARK_LOCAL) {
        assignment = insn.getSources().get(0);
    } else {
        assignment = getResult();
    }

    if (assignment == null) {
        return null;
    }

    LocalItem local = assignment.getLocalItem();

    if (local == null) {
        return null;
    }

    return assignment;
}
 

/**
 * Looks forward to the current block's primary successor, returning
 * the RegisterSpec of the result of the move-result-pseudo at the
 * top of that block or null if none.
 *
 * @return {@code null-ok;} result of move-result-pseudo at the beginning of
 * primary successor
 */
private RegisterSpec getNextMoveResultPseudo()
{
    int label = block.getPrimarySuccessor();

    if (label < 0) {
        return null;
    }

    Insn insn
            = method.getBlocks().labelToBlock(label).getInsns().get(0);

    if (insn.getOpcode().getOpcode() != RegOps.MOVE_RESULT_PSEUDO) {
        return null;
    } else {
        return insn.getResult();
    }
}
 

/**
 * Checks to see if the given SSA reg is ever associated with a local
 * local variable. Each SSA reg may be associated with at most one
 * local var.
 *
 * @param spec {@code non-null;} ssa reg
 * @return true if reg is ever associated with a local
 */
public boolean isRegALocal(RegisterSpec spec) {
    SsaInsn defn = getDefinitionForRegister(spec.getReg());

    if (defn == null) {
        // version 0 registers are never used as locals
        return false;
    }

    // Does the definition have a local associated with it?
    if (defn.getLocalAssignment() != null) return true;

    // If not, is there a mark-local insn?
    for (SsaInsn use : getUseListForRegister(spec.getReg())) {
        Insn insn = use.getOriginalRopInsn();

        if (insn != null
                && insn.getOpcode().getOpcode() == RegOps.MARK_LOCAL) {
            return true;
        }
    }

    return false;
}
 

/**
 * Looks forward to the current block's primary successor, returning
 * the RegisterSpec of the result of the move-result-pseudo at the
 * top of that block or null if none.
 *
 * @return {@code null-ok;} result of move-result-pseudo at the beginning of
 * primary successor
 */
private RegisterSpec getNextMoveResultPseudo()
{
    int label = block.getPrimarySuccessor();

    if (label < 0) {
        return null;
    }

    Insn insn
            = method.getBlocks().labelToBlock(label).getInsns().get(0);

    if (insn.getOpcode().getOpcode() != RegOps.MOVE_RESULT_PSEUDO) {
        return null;
    } else {
        return insn.getResult();
    }
}
 

/**
 * Replaces the instructions that define an array with equivalent registers.
 * For each entry in the array, a register is created, initialized to zero.
 * A mapping between this register and the corresponding array index is
 * added.
 *
 * @param def {@code non-null;} move result instruction for array
 * @param prev {@code non-null;} instruction for instantiating new array
 * @param length size of the new array
 * @param newRegs {@code non-null;} mapping of array indices to new
 * registers to be populated
 */
private void replaceDef(SsaInsn def, SsaInsn prev, int length,
                            ArrayList<RegisterSpec> newRegs) {
    Type resultType = def.getResult().getType();

    // Create new zeroed out registers for each element in the array
    for (int i = 0; i < length; i++) {
        Constant newZero = Zeroes.zeroFor(resultType.getComponentType());
        TypedConstant typedZero = (TypedConstant) newZero;
        RegisterSpec newReg =
            RegisterSpec.make(ssaMeth.makeNewSsaReg(), typedZero);
        newRegs.add(newReg);
        insertPlainInsnBefore(def, RegisterSpecList.EMPTY, newReg,
                                  RegOps.CONST, newZero);
    }
}
 

/**
 * Gets the parameter index for SSA registers that are method parameters.
 * {@code -1} is returned for non-parameter registers.
 *
 * @param ssaReg {@code >=0;} SSA register to look up
 * @return parameter index or {@code -1} if not a parameter
 */
private int getParameterIndexForReg(int ssaReg) {
    SsaInsn defInsn = ssaMeth.getDefinitionForRegister(ssaReg);
    if (defInsn == null) {
        return -1;
    }

    Rop opcode = defInsn.getOpcode();

    // opcode == null for phi insns.
    if (opcode != null && opcode.getOpcode() == RegOps.MOVE_PARAM) {
        CstInsn origInsn = (CstInsn) defInsn.getOriginalRopInsn();
        return  ((CstInteger) origInsn.getConstant()).getValue();
    }

    return -1;
}
 

/**
 * {@inheritDoc}
 *
 * TODO: Increase the scope of this.
 */
@Override
public boolean hasSideEffect() {
    Rop opcode = getOpcode();

    if (opcode.getBranchingness() != Rop.BRANCH_NONE) {
        return true;
    }

    boolean hasLocalSideEffect
        = Optimizer.getPreserveLocals() && getLocalAssignment() != null;

    switch (opcode.getOpcode()) {
        case RegOps.MOVE_RESULT:
        case RegOps.MOVE:
        case RegOps.CONST:
            return hasLocalSideEffect;
        default:
            return true;
    }
}
 

/**
 * Replaces the instructions that define an array with equivalent registers.
 * For each entry in the array, a register is created, initialized to zero.
 * A mapping between this register and the corresponding array index is
 * added.
 *
 * @param def {@code non-null;} move result instruction for array
 * @param prev {@code non-null;} instruction for instantiating new array
 * @param length size of the new array
 * @param newRegs {@code non-null;} mapping of array indices to new
 * registers to be populated
 */
private void replaceDef(SsaInsn def, SsaInsn prev, int length,
                            ArrayList<RegisterSpec> newRegs) {
    Type resultType = def.getResult().getType();

    // Create new zeroed out registers for each element in the array
    for (int i = 0; i < length; i++) {
        Constant newZero = Zeroes.zeroFor(resultType.getComponentType());
        TypedConstant typedZero = (TypedConstant) newZero;
        RegisterSpec newReg =
            RegisterSpec.make(ssaMeth.makeNewSsaReg(), typedZero);
        newRegs.add(newReg);
        insertPlainInsnBefore(def, RegisterSpecList.EMPTY, newReg,
                                  RegOps.CONST, newZero);
    }
}
 

/** {@inheritDoc} */
@Override
public RegisterSpec getLocalAssignment() {
    RegisterSpec assignment;

    if (insn.getOpcode().getOpcode() == RegOps.MARK_LOCAL) {
        assignment = insn.getSources().get(0);
    } else {
        assignment = getResult();
    }

    if (assignment == null) {
        return null;
    }

    LocalItem local = assignment.getLocalItem();

    if (local == null) {
        return null;
    }

    return assignment;
}
 

/**
 * Process a single instruction, looking for new objects resulting from
 * move result or move param.
 *
 * @param insn {@code non-null;} instruction to process
 */
private void processInsn(SsaInsn insn) {
    int op = insn.getOpcode().getOpcode();
    RegisterSpec result = insn.getResult();
    EscapeSet escSet;

    // Identify new objects
    if (op == RegOps.MOVE_RESULT_PSEUDO &&
            result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Handle objects generated through move_result_pseudo
        escSet = processMoveResultPseudoInsn(insn);
        processRegister(result, escSet);
    } else if (op == RegOps.MOVE_PARAM &&
                  result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Track method arguments that are objects
        escSet = new EscapeSet(result.getReg(), regCount, EscapeState.NONE);
        latticeValues.add(escSet);
        processRegister(result, escSet);
    } else if (op == RegOps.MOVE_RESULT &&
            result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Track method return values that are objects
        escSet = new EscapeSet(result.getReg(), regCount, EscapeState.NONE);
        latticeValues.add(escSet);
        processRegister(result, escSet);
    }
}
 

/**
 * {@inheritDoc}
 *
 * TODO: Increase the scope of this.
 */
@Override
public boolean hasSideEffect() {
    Rop opcode = getOpcode();

    if (opcode.getBranchingness() != Rop.BRANCH_NONE) {
        return true;
    }

    boolean hasLocalSideEffect
        = Optimizer.getPreserveLocals() && getLocalAssignment() != null;

    switch (opcode.getOpcode()) {
        case RegOps.MOVE_RESULT:
        case RegOps.MOVE:
        case RegOps.CONST:
            return hasLocalSideEffect;
        default:
            return true;
    }
}
 

/**
 * Process a single instruction, looking for new objects resulting from
 * move result or move param.
 *
 * @param insn {@code non-null;} instruction to process
 */
private void processInsn(SsaInsn insn) {
    int op = insn.getOpcode().getOpcode();
    RegisterSpec result = insn.getResult();
    EscapeSet escSet;

    // Identify new objects
    if (op == RegOps.MOVE_RESULT_PSEUDO &&
            result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Handle objects generated through move_result_pseudo
        escSet = processMoveResultPseudoInsn(insn);
        processRegister(result, escSet);
    } else if (op == RegOps.MOVE_PARAM &&
                  result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Track method arguments that are objects
        escSet = new EscapeSet(result.getReg(), regCount, EscapeState.NONE);
        latticeValues.add(escSet);
        processRegister(result, escSet);
    } else if (op == RegOps.MOVE_RESULT &&
            result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Track method return values that are objects
        escSet = new EscapeSet(result.getReg(), regCount, EscapeState.NONE);
        latticeValues.add(escSet);
        processRegister(result, escSet);
    }
}
 

/**
 * Gets the parameter index for SSA registers that are method parameters.
 * {@code -1} is returned for non-parameter registers.
 *
 * @param ssaReg {@code >=0;} SSA register to look up
 * @return parameter index or {@code -1} if not a parameter
 */
private int getParameterIndexForReg(int ssaReg) {
    SsaInsn defInsn = ssaMeth.getDefinitionForRegister(ssaReg);
    if (defInsn == null) {
        return -1;
    }

    Rop opcode = defInsn.getOpcode();

    // opcode == null for phi insns.
    if (opcode != null && opcode.getOpcode() == RegOps.MOVE_PARAM) {
        CstInsn origInsn = (CstInsn) defInsn.getOriginalRopInsn();
        return  ((CstInteger) origInsn.getConstant()).getValue();
    }

    return -1;
}
 

/**
 * Checks to see if the given SSA reg is ever associated with a local
 * local variable. Each SSA reg may be associated with at most one
 * local var.
 *
 * @param spec {@code non-null;} ssa reg
 * @return true if reg is ever associated with a local
 */
public boolean isRegALocal(RegisterSpec spec) {
    SsaInsn defn = getDefinitionForRegister(spec.getReg());

    if (defn == null) {
        // version 0 registers are never used as locals
        return false;
    }

    // Does the definition have a local associated with it?
    if (defn.getLocalAssignment() != null) return true;

    // If not, is there a mark-local insn?
    for (SsaInsn use : getUseListForRegister(spec.getReg())) {
        Insn insn = use.getOriginalRopInsn();

        if (insn != null
                && insn.getOpcode().getOpcode() == RegOps.MARK_LOCAL) {
            return true;
        }
    }

    return false;
}
 

/**
 * Gets the parameter index for SSA registers that are method parameters.
 * {@code -1} is returned for non-parameter registers.
 *
 * @param ssaReg {@code >=0;} SSA register to look up
 * @return parameter index or {@code -1} if not a parameter
 */
private int getParameterIndexForReg(int ssaReg) {
    SsaInsn defInsn = ssaMeth.getDefinitionForRegister(ssaReg);
    if (defInsn == null) {
        return -1;
    }

    Rop opcode = defInsn.getOpcode();

    // opcode == null for phi insns.
    if (opcode != null && opcode.getOpcode() == RegOps.MOVE_PARAM) {
        CstInsn origInsn = (CstInsn) defInsn.getOriginalRopInsn();
        return  ((CstInteger) origInsn.getConstant()).getValue();
    }

    return -1;
}
 

/**
 * Looks forward to the current block's primary successor, returning
 * the RegisterSpec of the result of the move-result-pseudo at the
 * top of that block or null if none.
 *
 * @return {@code null-ok;} result of move-result-pseudo at the beginning of
 * primary successor
 */
private RegisterSpec getNextMoveResultPseudo()
{
    int label = block.getPrimarySuccessor();

    if (label < 0) {
        return null;
    }

    Insn insn
            = method.getBlocks().labelToBlock(label).getInsns().get(0);

    if (insn.getOpcode().getOpcode() != RegOps.MOVE_RESULT_PSEUDO) {
        return null;
    } else {
        return insn.getResult();
    }
}
 

/**
 * {@inheritDoc}
 *
 * TODO: Increase the scope of this.
 */
@Override
public boolean hasSideEffect() {
    Rop opcode = getOpcode();

    if (opcode.getBranchingness() != Rop.BRANCH_NONE) {
        return true;
    }

    boolean hasLocalSideEffect
        = Optimizer.getPreserveLocals() && getLocalAssignment() != null;

    switch (opcode.getOpcode()) {
        case RegOps.MOVE_RESULT:
        case RegOps.MOVE:
        case RegOps.CONST:
            return hasLocalSideEffect;
        default:
            return true;
    }
}
 

/** {@inheritDoc} */
@Override
public RegisterSpec getLocalAssignment() {
    RegisterSpec assignment;

    if (insn.getOpcode().getOpcode() == RegOps.MARK_LOCAL) {
        assignment = insn.getSources().get(0);
    } else {
        assignment = getResult();
    }

    if (assignment == null) {
        return null;
    }

    LocalItem local = assignment.getLocalItem();

    if (local == null) {
        return null;
    }

    return assignment;
}
 

/**
 * Process a single instruction, looking for new objects resulting from
 * move result or move param.
 *
 * @param insn {@code non-null;} instruction to process
 */
private void processInsn(SsaInsn insn) {
    int op = insn.getOpcode().getOpcode();
    RegisterSpec result = insn.getResult();
    EscapeSet escSet;

    // Identify new objects
    if (op == RegOps.MOVE_RESULT_PSEUDO &&
            result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Handle objects generated through move_result_pseudo
        escSet = processMoveResultPseudoInsn(insn);
        processRegister(result, escSet);
    } else if (op == RegOps.MOVE_PARAM &&
                  result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Track method arguments that are objects
        escSet = new EscapeSet(result.getReg(), regCount, EscapeState.NONE);
        latticeValues.add(escSet);
        processRegister(result, escSet);
    } else if (op == RegOps.MOVE_RESULT &&
            result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Track method return values that are objects
        escSet = new EscapeSet(result.getReg(), regCount, EscapeState.NONE);
        latticeValues.add(escSet);
        processRegister(result, escSet);
    }
}
 

/**
 * Replaces the instructions that define an array with equivalent registers.
 * For each entry in the array, a register is created, initialized to zero.
 * A mapping between this register and the corresponding array index is
 * added.
 *
 * @param def {@code non-null;} move result instruction for array
 * @param prev {@code non-null;} instruction for instantiating new array
 * @param length size of the new array
 * @param newRegs {@code non-null;} mapping of array indices to new
 * registers to be populated
 */
private void replaceDef(SsaInsn def, SsaInsn prev, int length,
                            ArrayList<RegisterSpec> newRegs) {
    Type resultType = def.getResult().getType();

    // Create new zeroed out registers for each element in the array
    for (int i = 0; i < length; i++) {
        Constant newZero = Zeroes.zeroFor(resultType.getComponentType());
        TypedConstant typedZero = (TypedConstant) newZero;
        RegisterSpec newReg =
            RegisterSpec.make(ssaMeth.makeNewSsaReg(), typedZero);
        newRegs.add(newReg);
        insertPlainInsnBefore(def, RegisterSpecList.EMPTY, newReg,
                                  RegOps.CONST, newZero);
    }
}
 

/**
 * Replaces the instructions that define an array with equivalent registers.
 * For each entry in the array, a register is created, initialized to zero.
 * A mapping between this register and the corresponding array index is
 * added.
 *
 * @param def {@code non-null;} move result instruction for array
 * @param prev {@code non-null;} instruction for instantiating new array
 * @param length size of the new array
 * @param newRegs {@code non-null;} mapping of array indices to new
 * registers to be populated
 */
private void replaceDef(SsaInsn def, SsaInsn prev, int length,
                            ArrayList<RegisterSpec> newRegs) {
    Type resultType = def.getResult().getType();

    // Create new zeroed out registers for each element in the array
    for (int i = 0; i < length; i++) {
        Constant newZero = Zeroes.zeroFor(resultType.getComponentType());
        TypedConstant typedZero = (TypedConstant) newZero;
        RegisterSpec newReg =
            RegisterSpec.make(ssaMeth.makeNewSsaReg(), typedZero);
        newRegs.add(newReg);
        insertPlainInsnBefore(def, RegisterSpecList.EMPTY, newReg,
                                  RegOps.CONST, newZero);
    }
}
 

/**
 * Process a single instruction, looking for new objects resulting from
 * move result or move param.
 *
 * @param insn {@code non-null;} instruction to process
 */
private void processInsn(SsaInsn insn) {
    int op = insn.getOpcode().getOpcode();
    RegisterSpec result = insn.getResult();
    EscapeSet escSet;

    // Identify new objects
    if (op == RegOps.MOVE_RESULT_PSEUDO &&
            result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Handle objects generated through move_result_pseudo
        escSet = processMoveResultPseudoInsn(insn);
        processRegister(result, escSet);
    } else if (op == RegOps.MOVE_PARAM &&
                  result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Track method arguments that are objects
        escSet = new EscapeSet(result.getReg(), regCount, EscapeState.NONE);
        latticeValues.add(escSet);
        processRegister(result, escSet);
    } else if (op == RegOps.MOVE_RESULT &&
            result.getTypeBearer().getBasicType() == Type.BT_OBJECT) {
        // Track method return values that are objects
        escSet = new EscapeSet(result.getReg(), regCount, EscapeState.NONE);
        latticeValues.add(escSet);
        processRegister(result, escSet);
    }
}
 

/** {@inheritDoc} */
@Override
public RegisterSpec getLocalAssignment() {
    RegisterSpec assignment;

    if (insn.getOpcode().getOpcode() == RegOps.MARK_LOCAL) {
        assignment = insn.getSources().get(0);
    } else {
        assignment = getResult();
    }

    if (assignment == null) {
        return null;
    }

    LocalItem local = assignment.getLocalItem();

    if (local == null) {
        return null;
    }

    return assignment;
}
 

/**
 * Looks forward to the current block's primary successor, returning
 * the RegisterSpec of the result of the move-result-pseudo at the
 * top of that block or null if none.
 *
 * @return {@code null-ok;} result of move-result-pseudo at the beginning of
 * primary successor
 */
private RegisterSpec getNextMoveResultPseudo()
{
    int label = block.getPrimarySuccessor();

    if (label < 0) {
        return null;
    }

    Insn insn
            = method.getBlocks().labelToBlock(label).getInsns().get(0);

    if (insn.getOpcode().getOpcode() != RegOps.MOVE_RESULT_PSEUDO) {
        return null;
    } else {
        return insn.getResult();
    }
}
 

/**
 * {@inheritDoc}
 *
 * TODO: Increase the scope of this.
 */
@Override
public boolean hasSideEffect() {
    Rop opcode = getOpcode();

    if (opcode.getBranchingness() != Rop.BRANCH_NONE) {
        return true;
    }

    boolean hasLocalSideEffect
        = Optimizer.getPreserveLocals() && getLocalAssignment() != null;

    switch (opcode.getOpcode()) {
        case RegOps.MOVE_RESULT:
        case RegOps.MOVE:
        case RegOps.CONST:
            return hasLocalSideEffect;
        default:
            return true;
    }
}
 

/**
 * Gets the parameter index for SSA registers that are method parameters.
 * {@code -1} is returned for non-parameter registers.
 *
 * @param ssaReg {@code >=0;} SSA register to look up
 * @return parameter index or {@code -1} if not a parameter
 */
private int getParameterIndexForReg(int ssaReg) {
    SsaInsn defInsn = ssaMeth.getDefinitionForRegister(ssaReg);
    if (defInsn == null) {
        return -1;
    }

    Rop opcode = defInsn.getOpcode();

    // opcode == null for phi insns.
    if (opcode != null && opcode.getOpcode() == RegOps.MOVE_PARAM) {
        CstInsn origInsn = (CstInsn) defInsn.getOriginalRopInsn();
        return  ((CstInteger) origInsn.getConstant()).getValue();
    }

    return -1;
}
 

/**
 * Checks to see if the given SSA reg is ever associated with a local
 * local variable. Each SSA reg may be associated with at most one
 * local var.
 *
 * @param spec {@code non-null;} ssa reg
 * @return true if reg is ever associated with a local
 */
public boolean isRegALocal(RegisterSpec spec) {
    SsaInsn defn = getDefinitionForRegister(spec.getReg());

    if (defn == null) {
        // version 0 registers are never used as locals
        return false;
    }

    // Does the definition have a local associated with it?
    if (defn.getLocalAssignment() != null) return true;

    // If not, is there a mark-local insn?
    for (SsaInsn use : getUseListForRegister(spec.getReg())) {
        Insn insn = use.getOriginalRopInsn();

        if (insn != null
                && insn.getOpcode().getOpcode() == RegOps.MARK_LOCAL) {
            return true;
        }
    }

    return false;
}
 

/**
 * Returns true if the definition site of this register is a
 * move-param (ie, this is a method parameter).
 *
 * @param reg register in question
 * @return {@code true} if this is a method parameter
 */
protected boolean isDefinitionMoveParam(int reg) {
    SsaInsn defInsn = ssaMeth.getDefinitionForRegister(reg);

    if (defInsn instanceof NormalSsaInsn) {
        NormalSsaInsn ndefInsn = (NormalSsaInsn) defInsn;

        return ndefInsn.getOpcode().getOpcode() == RegOps.MOVE_PARAM;
    }

    return false;
}
 

/**
 * Checks to see if the move-param instructions that occur in this
 * method happen to slot the params in an order at the top of the
 * stack frame that matches dalvik's calling conventions. This will
 * alway result in "true" for methods that have run through the
 * SSA optimizer.
 *
 * @param paramSize size, in register units, of all the parameters
 * to this method
 */
private static boolean calculateParamsAreInOrder(RopMethod method,
        final int paramSize) {
    final boolean[] paramsAreInOrder = { true };
    final int initialRegCount = method.getBlocks().getRegCount();

    /*
     * We almost could just check the first block here, but the
     * {@code cf} layer will put in a second move-param in a
     * subsequent block in the case of synchronized methods.
     */
    method.getBlocks().forEachInsn(new Insn.BaseVisitor() {
        @Override
        public void visitPlainCstInsn(PlainCstInsn insn) {
            if (insn.getOpcode().getOpcode()== RegOps.MOVE_PARAM) {
                int param =
                    ((CstInteger) insn.getConstant()).getValue();

                paramsAreInOrder[0] = paramsAreInOrder[0]
                        && ((initialRegCount - paramSize + param)
                            == insn.getResult().getReg());
            }
        }
    });

    return paramsAreInOrder[0];
}