rubyx/lib/core/kernel.rb
2014-05-19 17:32:41 +03:00

114 lines
4.4 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 , string = Vm::Integer , length = Vm::Integer
function = Vm::Function.new(:putstring , [string , length ] , string)
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 , arg = Vm::Integer
putint_function = Vm::Function.new(:putint , [arg] , arg )
buffer = Vm::StringConstant.new(" ") # create a buffer
context.program.add_object buffer # and save it (function local variable: a no no)
int = putint_function.args.first
moved_int = Vm::Integer.new(1)
utoa = context.program.get_or_create_function(:utoa)
b = putint_function.body
b.mov( moved_int , int ) #move arg up
#b.a buffer => int # string to write to
b.add( int , buffer ,nil ) # string to write to
b.a int + (buffer.length-3) => int
b.call( utoa )
# And now we "just" have to print it, using the write_stdout
b.add( int , buffer , nil ) # string to write to
b.mov( moved_int , buffer.length )
Vm::CMachine.instance.write_stdout(putint_function.body)
putint_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
# arguments: string address , integer
def utoa context
utoa_function = Vm::Function.new(:utoa , [Vm::Integer , Vm::Integer ] , Vm::Integer )
str_addr = utoa_function.args[0]
number = utoa_function.args[1]
remainder = Vm::Integer.new( number.register + 1)
Vm::CMachine.instance.div10( utoa_function.body , number , remainder )
# make char out of digit (by using ascii encoding) 48 == "0"
b = utoa_function.body
b.a remainder + 48 => remainder
b.strb( remainder, right: str_addr )
b.sub( str_addr, str_addr , 1 )
b.cmp( number , 0 )
b.callne( utoa_function )
return utoa_function
end
# testing method, hand coded fibo, expects arg in 1 , so pass 2 in, first bogy
# result comes in 0
# a hand coded version of the fibonachi numbers
# not my hand off course, found in the net from a basic introduction
def fibo context
fibo_function = Vm::Function.new(:fibo , [Vm::Integer , Vm::Integer] , Vm::Integer )
result = fibo_function.args[0]
int =fibo_function.args[1]
i = Vm::Integer.new(2)
f1 = Vm::Integer.new(3)
f2 = Vm::Integer.new(4)
loop_block = Vm::Block.new("loop")
fibo_function.body.instance_eval do
cmp( int , 1)
mov( result, int , condition_code: :le)
mov( :pc , :lr , condition_code: :le)
push [ i , f1 , f2 , :lr]
mov( f1 , 1)
mov(f2 , 0)
sub( i , int , 2)
add_code loop_block
end
loop_block.instance_eval do
add( f1 , f1 , f2)
sub( f2 , f1 , f2)
sub( i , i , 1 , update_status: 1)
bpl( loop_block )
mov( result , f1 )
pop [ i , f1 , f2 , :pc]
end
fibo_function
end
end
extend ClassMethods
end
end