method.py 6.68 KB
Newer Older
Stefan Marr's avatar
Stefan Marr committed
1 2
from __future__ import absolute_import

3
from som.vmobjects.array import Array
Stefan Marr's avatar
Stefan Marr committed
4

5
from som.interpreter.bytecodes import bytecode_length
Stefan Marr's avatar
Stefan Marr committed
6 7 8

from array import array

9
class Method(Array):
Stefan Marr's avatar
Stefan Marr committed
10 11 12 13 14 15 16 17 18 19
    
    # Static field indices and number of method fields
    NUMBER_OF_LOCALS_INDEX                 = 1 + Array.CLASS_INDEX
    MAXIMUM_NUMBER_OF_STACK_ELEMENTS_INDEX = 1 + NUMBER_OF_LOCALS_INDEX
    SIGNATURE_INDEX                        = 1 + MAXIMUM_NUMBER_OF_STACK_ELEMENTS_INDEX
    HOLDER_INDEX                           = 1 + SIGNATURE_INDEX
    NUMBER_OF_METHOD_FIELDS                = 1 + HOLDER_INDEX

    
    def __init__(self, nilObject):
20
        Array.__init__(self, nilObject)
Stefan Marr's avatar
Stefan Marr committed
21 22 23 24 25 26 27 28 29 30 31 32 33
        
        self._receiver_class_table   = []
        self._invoked_methods        = []
        self._receiver_class_index   = 0

        self._invocation_count       = 0

        self._bytecodes              = None
        self._inline_cache_class     = None
        self._inline_cache_invokable = None
    
    def is_primitive(self):
        return False
34 35 36 37 38 39
    
    def is_invokable(self):
        """In the RPython version, we use this method to identify methods 
           and primitives
        """
        return True
Stefan Marr's avatar
Stefan Marr committed
40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76
  
    def get_number_of_locals(self):
        # Get the number of locals (converted to a Java integer)
        return self.get_field(self.NUMBER_OF_LOCALS_INDEX)

    def set_number_of_locals(self, value):
        # Set the number of locals
        self.set_field(self.NUMBER_OF_LOCALS_INDEX, value)

    def get_maximum_number_of_stack_elements(self):
        # Get the maximum number of stack elements
        return self.get_field(self.MAXIMUM_NUMBER_OF_STACK_ELEMENTS_INDEX)
  
    def set_maximum_number_of_stack_elements(self, value):
        # Set the maximum number of stack elements
        self.set_field(self.MAXIMUM_NUMBER_OF_STACK_ELEMENTS_INDEX, value)

    def get_signature(self):
        # Get the signature of this method by reading the field with signature
        # index
        return self.get_field(self.SIGNATURE_INDEX)

    def set_signature(self, value):
        # Set the signature of this method by writing to the field with
        # signature index
        self.set_field(self.SIGNATURE_INDEX, value)

    def get_holder(self):
        # Get the holder of this method by reading the field with holder index
        return self.get_field(self.HOLDER_INDEX)

    def set_holder(self, value):
        # Set the holder of this method by writing to the field with holder index
        self.set_field(self.HOLDER_INDEX, value)

        # Make sure all nested invokables have the same holder
        for i in range(0, self.get_number_of_indexable_fields()):
77
            if self.get_indexable_field(i).is_invokable():
Stefan Marr's avatar
Stefan Marr committed
78 79 80 81 82 83 84 85 86 87
                self.get_indexable_field(i).set_holder(value)

    def get_constant(self, bytecode_index):
        # Get the constant associated to a given bytecode index
        return self.get_indexable_field(self.get_bytecode(bytecode_index + 1))

    def get_number_of_arguments(self):
        # Get the number of arguments of this method
        return self.get_signature().get_number_of_signature_arguments()
  
88
    def _get_default_number_of_fields(self):
Stefan Marr's avatar
Stefan Marr committed
89 90 91 92 93 94 95 96 97
        # Return the default number of fields in a method
        return self.NUMBER_OF_METHOD_FIELDS
  
    def get_number_of_bytecodes(self):
        # Get the number of bytecodes in this method
        return len(self._bytecodes)

    def set_number_of_bytecodes(self, value):
        # Set the number of bytecodes in this method
98
        self._bytecodes              = ["\x00"] * value
Stefan Marr's avatar
Stefan Marr committed
99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126
        self._inline_cache_class     = [None] * value
        self._inline_cache_invokable = [None] * value

    def get_bytecode(self, index):
        # Get the bytecode at the given index
        return self._bytecodes[index]

    def set_bytecode(self, index, value):
        # Set the bytecode at the given index to the given value
        self._bytecodes[index] = value

    # TODO: remove these things
    def increase_invocation_counter(self):
        self._invocation_count += 1

    # TODO: remove these things
    def get_invocation_count(self):
        return self._invocation_count

    def invoke(self, frame, interpreter):
        # Increase the invocation counter
        self._invocation_count += 1
    
        # Allocate and push a new frame on the interpreter stack
        new_frame = interpreter.push_new_frame(self)
        new_frame.copy_arguments_from(frame)

    def replace_bytecodes(self):
127
        newbc =  ["\x00"] * len(self._bytecodes)
Stefan Marr's avatar
Stefan Marr committed
128 129 130 131 132
        idx = 0

        i = 0
        while i < len(self._bytecodes):
            bc1 = self._bytecodes[i]
133
            len1 = bytecode_length(bc1)
Stefan Marr's avatar
Stefan Marr committed
134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155

            if i + len1 >= len(self._bytecodes):
                # we're over target, so just copy bc1
                for j in range(i, i + len1):
                    newbc[idx] = self._bytecodes[j]
                    idx += 1
                break
    

            newbc[idx] = bc1
            idx += 1

            # copy args to bc1
            for j in range(i + 1, i + len1):
                newbc[idx] = self._bytecodes[j]
                idx += 1

            i += len1 # update i to point on bc2
    

        # we copy the new array because it may be shorter, and we don't
        # want to upset whatever dependence there is on the length
156
        self._bytecodes = array('b', [0] * idx)
Stefan Marr's avatar
Stefan Marr committed
157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192
        for i in range(0, idx):
            self._bytecodes[i] = newbc[i]

    # TODO: remove these things
    def get_receiver_class(self, index):
        return self._receiver_class_table[index]

    # TODO: remove these things
    def get_invoked_method(self, index):
        # return the last invoked method for a particular send
        return self._invoked_methods[index]

    # TODO: remove these things
    def add_receiver_class_and_method(self, rcvr_class, invokable):
        self._receiver_class_table.append(self._receiver_class_index, rcvr_class)
        self._invoked_methods.append(self._receiver_class_index, invokable)
        self._receiver_class_index += 1

        return self._receiver_class_index - 1

    # TODO: remove these things
    def is_receiver_class_table_full(self):
        return self._receiver_class_index == 255

    def __str__(self):
        return "Method(" + self.get_holder().get_name().get_string() + ">>" + str(self.get_signature()) + ")"

    def get_inline_cache_class(self, bytecode_index):
        return self._inline_cache_class[bytecode_index]

    def get_inline_cache_invokable(self, bytecode_index):
        return self._inline_cache_invokable[bytecode_index]

    def set_inline_cache(self, bytecode_index, receiver_class, invokable):
        self._inline_cache_class[bytecode_index]    = receiver_class
        self._inline_cache_invokable[bytecode_index] = invokable