rubyx/lib/vool/if_statement.rb
Torsten Rüger b9bdc55059 A good start on the macro idea
I call it macro because it lets you insert basically arbitrary risc code into the ruby level. The way it works:
Reserve namespace X
map any X.some_call to a Mom instruction
by the name SomeCall
which must take the same args in constructor as given
And obviously produce whatever risc it wants
Hoping to rewrite builtin around this idea (with the existing Mom builtn instructions)
2019-08-25 14:40:59 +03:00

61 lines
1.6 KiB
Ruby

module Vool
class IfStatement < Statement
attr_reader :condition , :if_true , :if_false
def initialize( cond , if_true , if_false = nil)
@condition = cond
@if_true = if_true
@if_false = if_false
end
def to_mom( compiler )
true_label = Mom::Label.new( self , "true_label_#{object_id.to_s(16)}")
false_label = Mom::Label.new( self , "false_label_#{object_id.to_s(16)}")
merge_label = Mom::Label.new( self , "merge_label_#{object_id.to_s(16)}")
if @condition.is_a?(CallStatement)
head = @condition.to_mom(compiler)
head << check_slot(compiler , false_label)
else
head = check_slot(compiler , false_label)
end
head << true_label
head << if_true.to_mom(compiler) if @if_true
head << Mom::Jump.new(merge_label) if @if_false
head << false_label
head << if_false.to_mom(compiler) if @if_false
head << merge_label if @if_false
head
end
# create the slot lazily, so to_mom gets called first
def check_slot(compiler , false_label)
Mom::TruthCheck.new(@condition.to_slot(compiler) , false_label)
end
def each(&block)
block.call(condition)
@if_true.each(&block) if @if_true
@if_false.each(&block) if @if_false
end
def has_false?
@if_false != nil
end
def has_true?
@if_true != nil
end
def to_s(depth = 0)
parts = ["if (#{@condition.to_s(0)})" ]
parts << " #{@if_true}" if @if_true
parts += [ "else" , " #{@if_false}"] if(@false)
parts << "end"
at_depth(depth , *parts )
end
end
end