rubyx/lib/core/kernel.rb

78 lines
3.5 KiB
Ruby

module Core
class Kernel
#there are no Kernel instances, only class methods.
# We use this module syntax to avoid the (ugly) self (also eases searching).
module ClassMethods
def main_start block
#TODO extract args into array of strings
Vm::CMachine.instance.main_start block
block
end
def main_exit block
# Machine.exit mov r7 , 0 + swi 0
Vm::CMachine.instance.main_exit block
block
end
def function_entry block , f_name
Vm::CMachine.instance.function_entry block , f_name
end
def function_exit block , f_name
Vm::CMachine.instance.function_exit block , f_name
end
#TODO this is in the wrong place. It is a function that returns a function object
# while all other methods add their code into some block. --> kernel
def putstring context
function = Vm::Function.new(:putstring , [Vm::Integer , Vm::Integer ] )
block = function.body
# should be another level of indirection, ie write(io,str)
ret = Vm::CMachine.instance.write_stdout(block)
function.return_type = ret
function
end
def putint context
function = Vm::Function.new(:putint , [Vm::Integer , Vm::Integer ] )
block = function.body
buffer = Vm::StringConstant.new(" ")
context.program.add_object buffer
str_addr = Vm::Integer.new(0) # address of the
reg1 = Vm::Integer.new(1)
block.add_code Vm::CMachine.instance.mov( reg1 , right: str_addr ) #move arg up
block.add_code Vm::CMachine.instance.add( str_addr , left: buffer ) # string to write to
block.add_code Vm::CMachine.instance.add( str_addr , left: str_addr , right: (buffer.length-3)) # string to write to
context.str_addr = str_addr
itos_fun = context.program.get_or_create_function(:utoa)
block.add_code Vm::CMachine.instance.call( itos_fun , {})
# And now we "just" have to print it, using the write_stdout
block.add_code Vm::CMachine.instance.add( str_addr , left: buffer ) # string to write to
block.add_code Vm::CMachine.instance.mov( reg1 , right: buffer.length )
ret = Vm::CMachine.instance.write_stdout(block)
function
end
# The conversion to base10 is quite a bit more complicated than i thought. The bulk of it is in div10
# We set up variables, do the devision and write the result to the string
# then check if were done and recurse if neccessary
# As we write before we recurse (save a push) we write the number backwards
def utoa context
function = Vm::Function.new(:utoa , [Vm::Integer , Vm::Integer ] )
block = function.body
str_addr = context.str_addr
number = Vm::Integer.new(str_addr.register + 1)
remainder = Vm::Integer.new( number.register + 1)
Vm::CMachine.instance.div10( block , number , remainder )
# make char out of digit (by using ascii encoding) 48 == "0"
block.add_code Vm::CMachine.instance.add( remainder , left: remainder , right: 48 )
block.add_code Vm::CMachine.instance.strb( remainder, right: str_addr )
block.add_code Vm::CMachine.instance.sub( str_addr, left: str_addr , right: 1 )
block.add_code Vm::CMachine.instance.cmp( number , right: 0 )
block.add_code Vm::CMachine.instance.callne( function , {} )
return function
end
end
extend ClassMethods
end
end