redoing the ifs with new (old) block structure

lib/ast/call_site_expression.rb

@@ -48,7 +48,7 @@ module Ast
       call.do_call into
       
       after = into.new_block("#{name}#{@@counter+=1}")
-      into.insert_at after
+      into.current after
       into.pop([]) unless current_function.nil?
       function.return_type
     end

lib/ast/if_expression.rb

@@ -1,28 +1,40 @@
 module Ast
   class IfExpression < Expression
 #    attr_reader  :cond, :if_true, :if_false
+
     def compile method , message
+      # to execute the logic as the if states it, the blocks are the other way around
+      # so we can the jump over the else if true ,and the else joins unconditionally after the true_block
+      merge_block = method.new_block "if_merge"    # last one, created first
+      true_block =  method.new_block "if_true"     # second, linked in after current, before merge
+      false_block = method.new_block "if_false"    # directly next in order, ie if we don't jump we land here
+      
+
       is = cond.compile(method,message)
-      #      is.is_false(frame,method)
       # TODO should/will use different branches for different conditions. 
-      branch = Virtual::ImplicitBranch.new "if_merge"
-      method.add_code branch
+      # just a scetch : cond_val = cond_val.is_true?(method) unless cond_val.is_a? Virtual::BranchCondition
+      method.add_code Virtual::ImplicitBranch.new( true_block )
+
+      # compile the true block (as we think of it first, even it is second in sequential order)
+      method.current true_block
       last = is
       if_true.each do |part|
         last = part.compile(method,message )
         raise part.inspect if last.nil?
       end
-      merge = Virtual::Label.new(branch.name)
-      method.add_code merge
-      branch.swap
-      method.current = branch
+
+      # compile the false block
+      method.current false_block
       if_false.each do |part|
-        last = part.compile(method,message )
+        puts "compiling in if false #{part}"
+        last = part.compile(method,message)
         raise part.inspect if last.nil?
       end
-      method.add_code merge
-      branch.swap
-      method.current = merge
+      method.add_code Virtual::UnconditionalBranch.new( merge_block )
+
+      puts "compiled if: end"
+      method.current merge_block
+
       #TODO should return the union of the true and false types
       last
     end

lib/boot/object.rb

@@ -34,7 +34,7 @@ module Boot
         index = get_function.call( index_function )
         
         after_body = get_function.new_block("after_index")
-        get_function.insert_at after_body
+        get_function.current after_body
         
         get_function.pop([me])
         return_to.at_index( get_function , me , return_to )
@@ -55,7 +55,7 @@ module Boot
         set_function.call( index_function )
         after_body = set_function.new_block("after_index")
         
-        set_function.insert_at after_body
+        set_function.current after_body
         set_function.pop([me])
         return_to.at_index( set_function , me , return_to )
         set_function.set_return return_to

lib/salama.rb

@@ -5,3 +5,4 @@ require 'salama-reader'
 require 'parser/transform'
 require "virtual/machine"
 require "ast/all"
+require "sof/all"

lib/virtual/instruction.rb

@@ -53,22 +53,14 @@ module Virtual
   class MethodReturn < Instruction
   end
 
-  # the next instruction represents the "true" branch and the other is the .... other
-  # could have been the false, but false is a keyword and is asymetric to next anyway
-  # this is an abstract base class (though no measures are taken to prevent instantiation) and derived
-  # class names indicate the actual test
+  # a branch must branch to a block. This is an abstract class, names indicate the actual test
   class Branch < Instruction
-    def initialize name , other = nil
-      unless(name.to_s.split("_").last.to_i > 0)
-        name = "#{name}_#{name.to_i(36) % 65536}".to_sym 
-      end
-      @name = name
-      @other = other
+    def initialize to
+      @to = to
     end
-    attr_reader :name
-    attr_accessor :other
+    attr_reader :to
     def attributes
-      [:name  , :other]
+      [:to]
     end
   end
 
@@ -77,6 +69,9 @@ module Virtual
   class ImplicitBranch < Branch
   end
 
+  class UnconditionalBranch < Branch
+  end
+
   class MessageGet < Instruction
     include Named
   end

test/virtual/test_methods.rb

@@ -40,7 +40,7 @@ def foo()
   2 + 5
 end
 HERE
-    @output = ""
+    @output = "---RETURN_MARKER- &1 !ruby/object:Virtual::MethodDefinitionRETURN_MARKER  name: :fooRETURN_MARKER  args: []RETURN_MARKER  locals: []RETURN_MARKER  tmps: []RETURN_MARKER  receiver: !ruby/object:Virtual::SelfReferenceRETURN_MARKER    clazz: RETURN_MARKER  return_type: !ruby/object:Virtual::ReturnRETURN_MARKER    name: :returnRETURN_MARKER    type: !ruby/class 'Virtual::Mystery'RETURN_MARKER  blocks:RETURN_MARKER  - &2 !ruby/object:Virtual::BlockRETURN_MARKER    method: *1RETURN_MARKER    name: :fooRETURN_MARKER    branch: RETURN_MARKER    codes:RETURN_MARKER    - !ruby/object:Virtual::MethodEnter {}RETURN_MARKER    - !ruby/object:Virtual::LoadSelfRETURN_MARKER      value: !ruby/object:Virtual::IntegerConstantRETURN_MARKER        integer: 2RETURN_MARKER    - !ruby/object:Virtual::MessageSendRETURN_MARKER      name: :+RETURN_MARKER      args:RETURN_MARKER      - !ruby/object:Virtual::IntegerConstantRETURN_MARKER        integer: 5RETURN_MARKER  - !ruby/object:Virtual::BlockRETURN_MARKER    method: *1RETURN_MARKER    name: :foo_returnRETURN_MARKER    branch: RETURN_MARKER    codes:RETURN_MARKER    - !ruby/object:Virtual::MethodReturn {}RETURN_MARKER  current: *2RETURN_MARKER"
     check
   end
 

test/virtual/virtual_helper.rb

@@ -11,7 +11,7 @@ module VirtualHelper
     machine = Virtual::Machine.boot
     expressions = machine.compile_main @string_input
     should = YAML.load(@output.gsub("RETURN_MARKER" , "\n"))
-    assert_equal should , expressions , expressions.to_yaml.gsub("\n" , "RETURN_MARKER") +  "\n" + expressions.to_yaml.gsub("!ruby/object:","") 
+    assert_equal should , expressions , expressions.to_yaml.gsub("\n" , "RETURN_MARKER") +  "\n" + Sof::Members.write(expressions)
   end
   
 end