rubyx/lib/risc/risc_value.rb
Torsten Ruger 9867234c38 move most code from method_compiler to builder
rather use builder in two ways, than sometimes compiler and sometimes
builder
Also makes it possible to reuse builtin code in mom’s to_risc, as both
use builder. The builtin code by directly adding to compiler, the mom
code not.
2018-04-08 18:51:20 +03:00

132 lines
3.8 KiB
Ruby

module Risc
# RiscValue is like a variable name, a storage location. The location is a register off course.
class RiscValue
attr_reader :symbol , :type , :value
attr_accessor :builder
def initialize( reg , type , value = nil)
raise "not reg #{reg}" unless self.class.look_like_reg( reg )
@type = type
@symbol = reg
@value = value
end
def to_s
s = "#{symbol}:#{type}"
s += ":#{value}" if value
s
end
def reg_no
@symbol.to_s[1 .. -1].to_i
end
def self.look_like_reg is_it
return true if is_it.is_a? RiscValue
return false unless is_it.is_a? Symbol
if( [:lr , :pc].include? is_it )
return true
end
if( (is_it.to_s.length <= 3) and (is_it.to_s[0] == "r"))
# could tighten this by checking that the rest is a number
return true
end
return false
end
def == other
return false if other.nil?
return false if other.class != RiscValue
symbol == other.symbol
end
#helper method to calculate with register symbols
def next_reg_use( type , value = nil )
int = @symbol[1,3].to_i
raise "No more registers #{self}" if int > 8
sym = "r#{int + 1}".to_sym
RiscValue.new( sym , type, value)
end
def sof_reference_name
@symbol
end
# can't overload "=" , so use shift for it.
# move the right side to the left. Left (this) is a RiscValue
# right value may be
# - constant (Parfait object) , resulting in a LoadConstant
# - another RiscValue, resulting in a Transfer instruction
# - an RValue, resulting in an SlotToReg
def <<( right )
case right
when Parfait::Object
ins = Risc.load_constant("#{right.class} to #{self.type}" , right , self)
when RiscValue
ins = Risc.transfer("#{right.type} to #{self.type}" , right , self)
when RValue
ins = Risc.slot_to_reg("#{right.register.type}[#{right.index}] -> #{self.type}" , right.register , right.index , self)
else
raise "not implemented"
end
builder.add_code(ins) if builder
return ins
end
def -( right )
raise "operators only on registers, not #{right.class}" unless right.is_a? RiscValue
op = Risc.op("#{self.type} - #{right.type}", :- , self , right )
builder.add_code(op) if builder
op
end
# just capture the values in an intermediary object (RValue)
# The RValue then gets used in a RegToSlot ot SlotToReg, where
# the values are unpacked to call Risc.reg_to_slot or Risc.slot_to_reg
def []( index )
RValue.new( self , index , builder)
end
end
# Just a struct, see comment for [] of RiscValue
#
class RValue
attr_reader :register , :index , :builder
def initialize(register, index , builder)
@register , @index , @builder = register , index , builder
end
# fullfil the objects purpose by creating a RegToSlot instruction from
# itself (the slot) and the register given
def <<( reg )
raise "not reg #{reg}" unless reg.is_a?(RiscValue)
reg_to_slot = Risc.reg_to_slot("#{reg.type} -> #{register.type}[#{index}]" , reg , register, index)
builder.add_code(reg_to_slot) if builder
reg_to_slot
end
end
# The register we use to store the current message object is :r0
def self.message_reg
RiscValue.new :r0 , :Message
end
# The register we use to store the new message object is :r3
# The new message is the one being built, to be sent
def self.new_message_reg
RiscValue.new :r1 , :Message
end
# The first scratch register. There is a next_reg_use to get a next and next.
# Current thinking is that scratch is schatch between instructions
def self.tmp_reg( type , value = nil)
RiscValue.new :r1 , type , value
end
end