rubyx/lib/register/instructions/function_call.rb
Torsten Ruger 35adf9a5e6 rename set_slot
set_slot was clear about the target, but not the source.
Better with reg_to_slot (and soon it’s inverse slot_to_reg)
2016-12-25 18:02:39 +02:00

35 lines
1.3 KiB
Ruby

module Register
# name says it all really
# only arg is the method object we want to call
# assembly takes care of the rest (ie getting the address)
class FunctionCall < Instruction
def initialize source , method
super(source)
@method = method
end
attr_reader :method
def to_s
"FunctionCall: #{method.name}"
end
end
def self.issue_call( compiler , callee )
source = "_issue_call(#{callee.name})"
return_label = Label.new("_return_label" , "#{compiler.type.object_class.name}.#{compiler.method.name}" )
ret_tmp = compiler.use_reg(:Label)
compiler.add_code Register::LoadConstant.new(source, return_label , ret_tmp)
compiler.add_code Register.reg_to_slot(source, ret_tmp , :new_message , :return_address)
# move the current new_message to message
compiler.add_code RegisterTransfer.new(source, Register.new_message_reg , Register.message_reg )
# do the register call
compiler.add_code FunctionCall.new( source , callee )
compiler.add_code return_label
# move the current message to new_message
compiler.add_code Register::RegisterTransfer.new(source, Register.message_reg , Register.new_message_reg )
# and restore the message from saved value in new_message
compiler.add_code Register.get_slot(source , :new_message , :caller , :message )
end
end