rubyx/lib/risc/instructions/syscall.rb
Torsten 17a7f29b0c define and use syscall_XX registers
rather than use hardcoded r0 etc use syscall_X
change the syscalls and interpreter to use them
later use platform to map from syscall_X to actually used register (like r0 in arm)
2020-03-22 14:31:43 +02:00

32 lines
834 B
Ruby

module Risc
# name says it all really
# only arg is the method syscall name
# how the layer below executes these is really up to it
# Any function issuing a Syscall should also save the current message
# and restore it after the syscall, saving the return value in Return_index
class Syscall < Instruction
def initialize source ,name
super(source)
@name = name
raise "must have name" unless name
end
attr_reader :name
def to_s
class_source name
end
end
# return the nth register that a sycall needs
# these map to different physical registers in the Platform
# first arg is (running 1..) integer, second (optional) type
def self.syscall_reg( number , type = nil)
type = :Integer unless type
RegisterValue.new("syscall_#{number}".to_sym , type)
end
end