rubyx/lib/register/instructions/function_call.rb
Torsten Ruger bc414fd3e8 function call now saves the return address before calling
that means SaveReturn is obsolete (breaks loads of tests)
first step towards multi - return which obviously can not have the
callee save return address.
In fact this would make FunctionCall redundant too, as it is really
just a branch
2015-11-03 11:20:49 +02:00

31 lines
1002 B
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" , "_return_label" )
ret_tmp = compiler.use_reg(:Label)
compiler.add_code Register::LoadConstant.new(source, return_label , ret_tmp)
compiler.add_code Register.set_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
end
end