add partial continuation stuff for maglev, for later use

lib/maglev/reflection/core_ext/exception.rb

@@ -0,0 +1,3 @@
+class Exception
+  primitive '__resume', 'resume:'
+end

lib/maglev/reflection/core_ext/proc.rb

@@ -0,0 +1,21 @@
+require File.expand_path("../method.rb", __FILE__)
+require File.expand_path("../thread.rb", __FILE__)
+
+class ExecBlock
+  primitive 'shift', 'shift'
+  primitive 'reset', 'reset'
+end
+
+class Proc
+  def __shift
+    @_st_block.shift
+  end
+
+  def __reset
+    @_st_block.reset
+  end
+end
+
+class Thread
+  primitive 'call', 'call:'
+end

lib/maglev/reflection/support/partial_continuation.rb

@@ -0,0 +1,50 @@
+class PartialContinuation
+  attr_accessor :markerBlock, :partial
+
+  def self.currentDomarkerBlock(block, markerBlock)
+    if (marker = markerBlock.call).nil?
+      raise RuntimeError, 'Marker not found when capturing partial continuation.'
+    end
+    return block.call to_offset_markerBlock(marker, 1, markerBlock)
+  end
+
+  def self.to_offset_markerBlock(method, offset, &block)
+    idx = find_frame_for(method)
+    partial = Thread.__partialContinuationFromLevel_to(3 + offset, idx)
+    new.tap do |o|
+      o.partial = partial
+      o.markerBlock = block
+    end
+  end
+
+  def self.find_frame_for(method)
+    index = 1
+    while frame = Thread.current.__frame_contents_at(index) do
+      if frame[0] == method
+        return level
+      else
+        level += 1
+      end
+    end
+    nil
+  end
+
+  def call(arg = nil)
+    marker = markerBlock.call
+    if marker.nil?
+      marker = Thread.current.__frame_contents_at(2).first
+      frameIndex = 2
+    else
+      frameIndex = self.class.find_frame_for marker
+    end
+    Thread.current.__installPartialContinuation_atLevel_value partial, frameIndex, arg
+  end
+
+  alias [] call
+end
+
+def test_callcc
+  PartialContinuation.currentDomarkerBlock
+  currentDo: aBlock 
+  markerBlock: [ self callbackMarker ]
+end