rubyx/lib/register/builtin/kernel.rb
2017-01-14 19:28:44 +02:00

70 lines
3.2 KiB
Ruby

module Register
module Builtin
module Kernel
module ClassMethods
# this is the really really first place the machine starts (apart from the jump here)
# it isn't really a function, ie it is jumped to (not called), exits and may not return
# so it is responsible for initial setup
def __init__ context
compiler = Vm::MethodCompiler.new.create_method(:Kernel,:__init__ )
new_start = Register.label("__init__ start" , "__init__" )
compiler.method.set_instructions( new_start)
compiler.set_current new_start
space = Parfait.object_space
space_reg = compiler.use_reg(:Space) #Set up the Space as self upon init
compiler.add_load_constant("__init__ load Space", space , space_reg)
message_ind = Register.resolve_to_index( :space , :first_message )
compiler.add_slot_to_reg( "__init__ load 1st message" , space_reg , message_ind , :message)
compiler.add_reg_to_slot( "__init__ store Space in message", space_reg , :message , :receiver)
#fixme: should add arg type here, as done in call_site (which this sort of is)
exit_label = Register.label("_exit_label for __init__" , "#{compiler.type.object_class.name}.#{compiler.method.name}" )
ret_tmp = compiler.use_reg(:Label)
compiler.add_load_constant("__init__ load return", exit_label , ret_tmp)
compiler.add_reg_to_slot("__init__ store return", ret_tmp , :message , :return_address)
compiler.add_code Register.function_call( "__init__ issue call" , Parfait.object_space.get_main )
compiler.add_code exit_label
emit_syscall( compiler , :exit )
return compiler.method
end
def exit context
compiler = Vm::MethodCompiler.new.create_method(:Kernel,:exit ).init_method
emit_syscall( compiler , :exit )
return compiler.method
end
def emit_syscall compiler , name
save_message( compiler )
compiler.add_code Syscall.new("emit_syscall(#{name})", name )
restore_message(compiler)
return unless (@clazz and @method)
compiler.add_label( "#{@clazz.name}.#{@message.name}" , "return_syscall" )
end
# save the current message, as the syscall destroys all context
#
# This relies on linux to save and restore all registers
#
def save_message(compiler)
r8 = RegisterValue.new( :r8 , :Message)
compiler.add_transfer("save_message", Register.message_reg , r8 )
end
def restore_message(compiler)
r8 = RegisterValue.new( :r8 , :Message)
return_tmp = Register.tmp_reg :Integer
source = "_restore_message"
# get the sys return out of the way
compiler.add_transfer(source, Register.message_reg , return_tmp )
# load the stored message into the base RegisterMachine
compiler.add_transfer(source, r8 , Register.message_reg )
# save the return value into the message
compiler.add_reg_to_slot( source , return_tmp , :message , :return_value )
end
end
extend ClassMethods
end
end
end