rubyx/lib/soml/compiler/while_statement.rb
Torsten Ruger 642dcb065a fix while statement
logic was broken, or inversed
had to lay the code out a bit funny, but it works and makes sense
2015-11-04 20:23:26 +02:00

30 lines
945 B
Ruby

module Soml
Compiler.class_eval do
def on_while_statement statement
#puts statement.inspect
branch_type , condition , statements = *statement
condition = condition.first
condition_label = Register::Label.new(statement , "condition_label")
# unconditionally branch to the condition upon entering the loop
add_code Register::Branch.new(statement,condition_label)
add_code start = Register::Label.new(statement , "while_start" )
reset_regs
process_all(statements)
# This is where the loop starts, though in subsequent iterations it's in the middle
add_code condition_label
reset_regs
process(condition)
branch_class = Object.const_get "Register::Is#{branch_type.capitalize}"
# this is where the while ends and both branches meet
add_code branch_class.new( condition , start )
nil # statements don't return anything
end
end
end