コード例 #1
0
ファイル: expression.py プロジェクト: holdenli/CS-444
def gen_creation_expr(info, node, method_obj):
    canon = node.find_child("Type").canon
    if canon.endswith('[]'):
        return gen_creation_expr_array(info, node, method_obj)
    
    output = ["; START gen_creation_expr"]

    # Number of bytes we will malloc (including metadata).
    num_bytes = info.get_size(canon)

    output.append("mov eax, %i" % num_bytes)
    output.append("push ebx") # Safety
    output.append("call __malloc")
    output.append("pop ebx") # Safety

    # Zero out fields.
    output.append('mov ebx, %d' % (num_bytes / 4))
    output.extend(util.gen_zero_out(info))

    output.append("mov dword [eax], SIT~%s" % canon)
    output.append("mov dword [eax+4], SBM~%s" % canon)
    output.append("mov dword [eax+8], 0") # Not an array, so 0.
    output.append("push eax ; this pointer")

    # calculate args, push args; left-to-right
    args = list(node.find_child("Arguments").children)
    num_args = len(args)
    arg_types = []
    for arg in args:
        output.extend(gen_expr(info, arg, method_obj))
        output.append("push eax")

        if typecheck.is_array_type(arg.typ) == True:
            # '[]'s replaced with '@', so that it can be accepted.
            arg_types.append(arg.typ[:-2] + '@')
        else:
            arg_types.append(arg.typ)

    constructor_name = canon.split(".")[-1]
    label = 'CONSTRUCTOR~%s.%s~%s' % (canon, constructor_name, '~'.join(arg_types))
    output.append("call %s" % label)

    # pop args
    output.append("add esp, %i" % (num_args*4))

    # put "this" on eax
    output.append("pop eax")

    output.append("; END gen_creation_expr")

    return output
コード例 #2
0
ファイル: expression.py プロジェクト: holdenli/CS-444
def gen_creation_expr_array(info, node, method_obj):
    canon = node.find_child("Type").canon
    assert canon.endswith('[]')
    canon = canon[:-2]
    if canon in primitives.primitive_types:
        canon = "@" + canon # add @ infront of primitives for SBM

    output = ["; START gen_creation_expr_array"]

    # put length of array in eax
    args = node.find_child("Arguments").children
    num_args = len(args)
    if num_args == 1:
        output.extend(gen_expr(info, args[0], method_obj)) # Array length in eax.
    else:
        assert num_args == 0
        output.append("mov eax 0")

    # Calculate number of bytes we need for the array.
    output.append('push eax') # Save array length.
    output.append('add eax, 4')
    output.append('push eax') # Save num words.
    output.append('shl eax, 2') # Multiply index (offset) by 4.

    # Allocate. eax has addr. 
    output.append('call __malloc')

    # Zero out array.
    output.append('pop ebx') # Num words.
    output.extend(util.gen_zero_out(info)) # eax = ptr, ebx = num words

    output.append('pop ebx') # Restore array length.

    # Object metadata.
    output.append("mov dword [eax], SIT~java.lang.Object")
    output.append("mov dword [eax+4], SBM~%s" % canon)
    output.append("mov dword [eax+8], 1")
    output.append("mov dword [eax+12], ebx") # Length

    output.append("; END gen_creation_expr_array")

    return output
コード例 #3
0
ファイル: expression.py プロジェクト: holdenli/CS-444
def gen_new_string(info, init_str):
    output = ['; gen_new_string']

    # First we make a char array with length equal to size of init_str
    num_chars = len(init_str)

    # Put number of bytes in eax.
    output.append('mov eax, %d' % ((num_chars + 4) * 4))

    # Calculate number of bytes we need for the array.

    # Allocate. eax has addr. 
    output.append('call __malloc')

    # Zero out array.
    output.append('mov ebx, %d' % (num_chars + 4))
    output.extend(util.gen_zero_out(info)) # eax = ptr, ebx = num words

    # Object metadata.
    output.append("mov dword [eax], SIT~java.lang.Object")
    output.append("mov dword [eax+4], SBM~@Char")
    output.append("mov dword [eax+8], 1")
    output.append("mov dword [eax+12], %d" % num_chars) # Length

    # Fill in elems.
    offset = 0
    for c in init_str:
        output.append('mov dword [eax+%d], %d' % (((offset + 4) * 4), ord(c)))
        offset += 1

    # Back up array.
    output.append('push eax')

    # Call a new string.

    # Number of bytes we will malloc (including metadata).
    num_bytes = info.get_size('java.lang.String')

    output.append("mov eax, %i" % num_bytes)
    output.append("call __malloc")

    # Zero out fields.
    output.append('mov ebx, %d' % (num_bytes / 4))
    output.extend(util.gen_zero_out(info))

    output.append("mov dword [eax], SIT~java.lang.String")
    output.append("mov dword [eax+4], SBM~java.lang.String")
    output.append("mov dword [eax+8], 0") # Not an array, so 0.

    # Get the char array.
    output.append('pop ebx')

    # Push the string addr, and the char array as an argument.
    output.append("push eax ; this pointer")
    output.append('push ebx')

    # Call the constructor.
    constructor_label = 'CONSTRUCTOR~java.lang.String.String~Char@'
    output.append("call %s" % constructor_label)

    # pop args (only 1)
    output.append("add esp, 4")

    # put "this" on eax
    output.append("pop eax")

    output.append("; END gen_new_string")
    return output