rubyx/lib/kernel/integer.rb
2014-07-12 21:59:17 +03:00

89 lines
3.5 KiB
Ruby

#integer related kernel functions
module Crystal
module Kernel
# 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 self.utoa context
utoa_function = Virtual::Method.new(:utoa , [ Virtual::Integer ] , Virtual::Integer ,Virtual::Integer )
return utoa_function
str_addr = utoa_function.receiver
number = utoa_function.args.first
remainder = utoa_function.new_local
Virtual::RegisterMachine.instance.div10( utoa_function , number , remainder )
# make char out of digit (by using ascii encoding) 48 == "0"
utoa_function.instance_eval do
add( remainder , remainder , 48)
strb( remainder, str_addr )
sub( str_addr, str_addr , 1 )
cmp( number , 0 )
callne( utoa_function )
end
return utoa_function
end
def self.putint context
putint_function = Virtual::Method.new(:putint , [] , Virtual::Integer ,Virtual::Integer )
return putint_function
buffer = Virtual::StringConstant.new(" ") # create a buffer
context.object_space.add_object buffer # and save it (function local variable: a no no)
int = putint_function.receiver
moved_int = putint_function.new_local
utoa = context.object_space.get_or_create_class(:Object).resolve_function(:utoa)
putint_function.instance_eval do
mov( moved_int , int ) # move arg up
add( int , buffer ,nil ) # string to write to (add string address to pc)
add( int , int , buffer.length - 3) # 3 for good measure , ahem.
call( utoa )
after = new_block("after_call")
insert_at after
# And now we "just" have to print it, using the write_stdout
add( int , buffer , nil ) # string to write to
mov( moved_int , buffer.length )
end
Virtual::RegisterMachine.instance.write_stdout(putint_function)
putint_function
end
# testing method, hand coded fibo, expects arg in receiver_register
# result comes in return_register
# a hand coded version of the fibonachi numbers
# not my hand off course, found in the net http://www.peter-cockerell.net/aalp/html/ch-5.html
def self.fibo context
fibo_function = Virtual::Method.new(:fibo , [] , Virtual::Integer ,Virtual::Integer )
return fibo_function
result = fibo_function.return_type
int = fibo_function.receiver
last = fibo_function.new_block("return")
f1 = fibo_function.new_local
f2 = fibo_function.new_local
fibo_function.instance_eval do
cmp int , 1
mov( result, int , condition_code: :le)
ble( last ) #branch to return, rather than return (as the original)
mov f1 , 1 #set up initial values
mov f2 , 0
end
loop = fibo_function.new_block("loop")
fibo_function.insert_at loop
fibo_function.instance_eval do #loop through
add f1 , f1 , f2 # f1 = f1 + f2
sub f2 , f1 , f2 # f2 = f1 -f2
sub int , int , 1 # todo: set.. should do below cmp, but doesn't , set_update_status: 1
cmp int , 1
bne( loop )
mov( result , f1 )
end
fibo_function
end
end
end