Remove all traces of rubyclass stack from the codebase.

* Removed klass arg from method calls. * Remove the push/pop/get from thread-context and use sites. * TODO: embed used to inject values into the current-module obtained from the rubyclass stack. That code needs investigation. * Replaced the hacky if (klass==null) prepareSelf(binding) calls with information about actual execution context. The primary reason to use binding.self instead of self argument in blocks is when the block is being used in a binding-eval context. The same soln. is applicable in other contexts where this pattern was used (and currently marked with SSS FIXME annotations in code comments).
jruby · Jun 29, 2014 · 525a110 · 525a110
1 parent 92833b9
commit 525a110
Showing 35 changed files with 146 additions and 269 deletions.
diff --git a/core/src/main/java/org/jruby/RubyArray.java b/core/src/main/java/org/jruby/RubyArray.java
@@ -3224,7 +3224,7 @@ private IRubyObject sortInternal(final ThreadContext context, final Block block)
             public int compare(Object o1, Object o2) {
                 IRubyObject obj1 = (IRubyObject) o1;
                 IRubyObject obj2 = (IRubyObject) o2;
-                IRubyObject ret = block.yieldArray(context, getRuntime().newArray(obj1, obj2), null, null);
+                IRubyObject ret = block.yieldArray(context, getRuntime().newArray(obj1, obj2), null);
                 //TODO: ary_sort_check should be done here
                 return RubyComparable.cmpint(context, ret, obj1, obj2);
             }

diff --git a/core/src/main/java/org/jruby/RubyBasicObject.java b/core/src/main/java/org/jruby/RubyBasicObject.java
@@ -42,7 +42,6 @@
 
 import org.jruby.anno.JRubyMethod;
 import org.jruby.common.IRubyWarnings.ID;
-import org.jruby.evaluator.ASTInterpreter;
 import org.jruby.exceptions.JumpException;
 import org.jruby.internal.runtime.methods.DynamicMethod;
 import org.jruby.javasupport.JavaObject;
@@ -1621,10 +1620,10 @@ protected IRubyObject yieldUnder(final ThreadContext context, RubyModule under,
         try {
             if (args.length == 1) {
                 IRubyObject valueInYield = args[0];
-                return setupBlock(block, evalType).yieldNonArray(context, valueInYield, this, context.getRubyClass());
+                return setupBlock(block, evalType).yieldNonArray(context, valueInYield, this); // context.getRubyClass());
             } else {
                 IRubyObject valueInYield = RubyArray.newArrayNoCopy(context.runtime, args);
-                return setupBlock(block, evalType).yieldArray(context, valueInYield, this, context.getRubyClass());
+                return setupBlock(block, evalType).yieldArray(context, valueInYield, this); // context.getRubyClass());
             }
             //TODO: Should next and return also catch here?
         } catch (JumpException.BreakJump bj) {
@@ -1662,7 +1661,7 @@ protected IRubyObject yieldUnder(final ThreadContext context, RubyModule under,
         block.getBinding().setVisibility(PUBLIC);
 
         try {
-            return setupBlock(block, evalType).yieldNonArray(context, this, this, context.getRubyClass());
+            return setupBlock(block, evalType).yieldNonArray(context, this, this); // context.getRubyClass());
             //TODO: Should next and return also catch here?
         } catch (JumpException.BreakJump bj) {
             return (IRubyObject) bj.getValue();

diff --git a/core/src/main/java/org/jruby/RubyEnumerable.java b/core/src/main/java/org/jruby/RubyEnumerable.java
@@ -763,7 +763,7 @@ public IRubyObject call(ThreadContext ctx, IRubyObject[] largs, Block blk) {
                         larg = RubyArray.newArrayNoCopy(ctx.runtime, largs);
                     }
 
-                    IRubyObject value = newAry ? block.yieldArray(ctx, larg, null, null) : block.yield(ctx, larg);
+                    IRubyObject value = newAry ? block.yieldArray(ctx, larg, null) : block.yield(ctx, larg);
                     synchronized (result) {
                         result.append(value);
                     }
@@ -828,7 +828,7 @@ public IRubyObject call(ThreadContext ctx, IRubyObject[] largs, Block blk) {
                 IRubyObject larg = packEnumValues(runtime, largs);
                 checkContext(localContext, ctx, "inject");
                 result[0] = result[0] == null ? 
-                        larg : block.yieldArray(ctx, runtime.newArray(result[0], larg), null, null);
+                        larg : block.yieldArray(ctx, runtime.newArray(result[0], larg), null);
 
                 return runtime.getNil();
             }
@@ -1135,7 +1135,7 @@ public IRubyObject call(ThreadContext ctx, IRubyObject[] largs, Block blk) {
                     IRubyObject larg = packEnumValues(runtime, largs);
                     checkContext(localContext, ctx, "max{}");
                     if (result[0] == null || RubyComparable.cmpint(ctx, block.yieldArray(ctx,
-                                                                                         runtime.newArray(larg, result[0]), null, null), larg, result[0]) > 0) {
+                                                                                         runtime.newArray(larg, result[0]), null), larg, result[0]) > 0) {
                         result[0] = larg;
                     }
                     return runtime.getNil();

diff --git a/core/src/main/java/org/jruby/RubyHash.java b/core/src/main/java/org/jruby/RubyHash.java
@@ -1364,7 +1364,7 @@ public void visit(IRubyObject key, IRubyObject value) {
                 if (oneNine) {
                     block.yield(context, RubyArray.newArray(runtime, key, value));
                 } else {
-                    block.yieldArray(context, RubyArray.newArray(runtime, key, value), null, null);
+                    block.yieldArray(context, RubyArray.newArray(runtime, key, value), null);
                 }
             }
         });
@@ -1604,7 +1604,7 @@ public IRubyObject select19(final ThreadContext context, final Block block) {
         iteratorVisitAll(new Visitor() {
             @Override
             public void visit(IRubyObject key, IRubyObject value) {
-                if (block.yieldArray(context, runtime.newArray(key, value), null, null).isTrue()) {
+                if (block.yieldArray(context, runtime.newArray(key, value), null).isTrue()) {
                     result.fastASet(key, value);
                 }
             }
@@ -1624,7 +1624,7 @@ public RubyHash delete_ifInternal(final ThreadContext context, final Block block
         iteratorVisitAll(new Visitor() {
             @Override
             public void visit(IRubyObject key, IRubyObject value) {
-                if (block.yieldArray(context, RubyArray.newArray(runtime, key, value), null, null).isTrue()) {
+                if (block.yieldArray(context, RubyArray.newArray(runtime, key, value), null).isTrue()) {
                     self.delete(context, key, Block.NULL_BLOCK);
                 }
             }

diff --git a/core/src/main/java/org/jruby/RubyProc.java b/core/src/main/java/org/jruby/RubyProc.java
@@ -146,7 +146,6 @@ private void setup(Block procBlock) {
                     oldBinding.getSelf(),
                     oldBinding.getFrame().duplicate(),
                     oldBinding.getVisibility(),
-                    oldBinding.getKlass(), 
                     oldBinding.getDynamicScope(),
                     oldBinding.getBacktrace().clone());
             block = new Block(procBlock.getBody(), newBinding);

diff --git a/core/src/main/java/org/jruby/RubyStruct.java b/core/src/main/java/org/jruby/RubyStruct.java
@@ -254,7 +254,7 @@ public DynamicMethod dup() {
         if (block.isGiven()) {
             // Struct bodies should be public by default, so set block visibility to public. JRUBY-1185.
             block.getBinding().setVisibility(Visibility.PUBLIC);
-            block.yieldNonArray(runtime.getCurrentContext(), null, newStruct, newStruct);
+            block.yieldNonArray(runtime.getCurrentContext(), null, newStruct);
         }
 
         return newStruct;

diff --git a/core/src/main/java/org/jruby/RubySymbol.java b/core/src/main/java/org/jruby/RubySymbol.java
@@ -391,7 +391,7 @@ private IRubyObject yieldInner(ThreadContext context, RubyArray array, Block blo
 
             @Override
             public IRubyObject yield(ThreadContext context, IRubyObject[] args, IRubyObject self,
-                    RubyModule klass, Binding binding, Block.Type type, Block block) {
+                                     Binding binding, Type type, Block block) {
                 RubyProc.prepareArgs(context, type, block.arity(), args);
                 return yieldInner(context, context.runtime.newArrayNoCopyLight(args), block);
             }
@@ -408,7 +408,7 @@ protected IRubyObject doYield(ThreadContext context, IRubyObject value, Binding
             }
 
             @Override
-            protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Type type) {
+            protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Type type) {
                 return yieldInner(context, context.runtime.newArrayNoCopyLight(args), Block.NULL_BLOCK);
             }
 

diff --git a/core/src/main/java/org/jruby/embed/variable/Argv.java b/core/src/main/java/org/jruby/embed/variable/Argv.java
@@ -128,7 +128,8 @@ public static boolean isValidName(Object name) {
     public void inject() {
         updateArgvByJavaObject();
         RubyModule rubyModule = getRubyClass(receiver.getRuntime());
-        if (rubyModule == null) rubyModule = receiver.getRuntime().getCurrentContext().getRubyClass();
+        // SSS FIXME: With rubyclass stack gone, this needs a replacement
+        if (rubyModule == null) rubyModule = null; // receiver.getRuntime().getCurrentContext().getRubyClass();
         if (rubyModule == null) return;
 
         rubyModule.storeConstant(name, irubyObject);

diff --git a/core/src/main/java/org/jruby/embed/variable/Constant.java b/core/src/main/java/org/jruby/embed/variable/Constant.java
@@ -218,7 +218,8 @@ public static boolean isValidName(Object name) {
     public void inject() {
         if (receiver == receiver.getRuntime().getTopSelf()) {
             RubyModule rubyModule = getRubyClass(receiver.getRuntime());
-            if (rubyModule == null) rubyModule = receiver.getRuntime().getCurrentContext().getRubyClass();
+            // SSS FIXME: With rubyclass stack gone, this needs a replacement
+            if (rubyModule == null) rubyModule = null; // receiver.getRuntime().getCurrentContext().getRubyClass();
             if (rubyModule == null) return;
 
             rubyModule.storeConstant(name, irubyObject);

diff --git a/core/src/main/java/org/jruby/ext/fiber/ThreadFiber.java b/core/src/main/java/org/jruby/ext/fiber/ThreadFiber.java
@@ -17,7 +17,6 @@
 import org.jruby.runtime.ThreadContext;
 import org.jruby.runtime.Visibility;
 import org.jruby.runtime.builtin.IRubyObject;
-import org.jruby.runtime.Visibility;
 
 import org.jruby.ir.runtime.IRBreakJump;
 import org.jruby.ir.runtime.IRReturnJump;
@@ -225,7 +224,7 @@ public void run() {
                         if (init == NEVER) {
                             result = block.yieldSpecific(context);
                         } else {
-                            result = block.yieldArray(context, init, null, null);
+                            result = block.yieldArray(context, init, null);
                         }
 
                         data.prev.data.queue.push(context, result);

diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/InterpretedIRMetaClassBody.java b/core/src/main/java/org/jruby/internal/runtime/methods/InterpretedIRMetaClassBody.java
@@ -25,7 +25,6 @@ public List<String[]> getParameterList() {
     protected void post(ThreadContext context) {
         // update call stacks (pop: ..)
         context.popFrame();
-        context.popRubyClass();
         context.popScope();
     }
 

diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/InterpretedIRMethod.java b/core/src/main/java/org/jruby/internal/runtime/methods/InterpretedIRMethod.java
@@ -123,7 +123,6 @@ public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule claz
     protected void post(ThreadContext context) {
         // update call stacks (pop: ..)
         context.popFrame();
-        context.popRubyClass();
         if (this.pushScope) {
             context.popScope();
         }

diff --git a/core/src/main/java/org/jruby/ir/IRScriptBody.java b/core/src/main/java/org/jruby/ir/IRScriptBody.java
@@ -116,7 +116,6 @@ public IRubyObject interpret(ThreadContext context, IRubyObject self) {
         } catch (IRBreakJump bj) {
             throw IRException.BREAK_LocalJumpError.getException(context.runtime);
         } finally {
-            context.popRubyClass();
             context.popScope();
         }
 

diff --git a/core/src/main/java/org/jruby/ir/interpreter/Interpreter.java b/core/src/main/java/org/jruby/ir/interpreter/Interpreter.java
@@ -393,7 +393,6 @@ private static void processBookKeepingOp(ThreadContext context, Instr instr, Ope
             break;
         case POP_FRAME:
             context.popFrame();
-            context.popRubyClass();
             break;
         case POP_BINDING:
             context.popScope();

diff --git a/core/src/main/java/org/jruby/ir/runtime/IRRuntimeHelpers.java b/core/src/main/java/org/jruby/ir/runtime/IRRuntimeHelpers.java
@@ -202,7 +202,7 @@ public static IRubyObject defCompiledIRMethod(ThreadContext context, MethodHandl
         Ruby runtime = context.runtime;
 
         // SSS FIXME: this has to be looked up at runtime now
-        RubyModule containingClass = context.getRubyClass();
+        RubyModule containingClass = null; // context.getRubyClass();
         Visibility currVisibility = context.getCurrentVisibility();
         Visibility newVisibility = Helpers.performNormalMethodChecksAndDetermineVisibility(runtime, containingClass, rubyName, currVisibility);
 
@@ -386,7 +386,7 @@ public static IRubyObject yield(ThreadContext context, Object blk, Object yieldA
         if (blk instanceof RubyNil) blk = Block.NULL_BLOCK;
         Block b = (Block)blk;
         IRubyObject yieldVal = (IRubyObject)yieldArg;
-        return (unwrapArray && (yieldVal instanceof RubyArray)) ? b.yieldArray(context, yieldVal, null, null) : b.yield(context, yieldVal);
+        return (unwrapArray && (yieldVal instanceof RubyArray)) ? b.yieldArray(context, yieldVal, null) : b.yield(context, yieldVal);
     }
 
     public static IRubyObject yieldSpecific(ThreadContext context, Object blk) {

diff --git a/core/src/main/java/org/jruby/runtime/Binding.java b/core/src/main/java/org/jruby/runtime/Binding.java
@@ -49,7 +49,6 @@ public class Binding {
      */
     private final Frame frame;
     private final BacktraceElement backtrace;
-    private final RubyModule klass;
 
     private Visibility visibility;
     /**
@@ -80,37 +79,34 @@ public class Binding {
     private Binding evalScopeBinding = this;
 
     public Binding(IRubyObject self, Frame frame,
-            Visibility visibility, RubyModule klass, DynamicScope dynamicScope, BacktraceElement backtrace) {
+                   Visibility visibility, DynamicScope dynamicScope, BacktraceElement backtrace) {
         this.self = self;
         this.frame = frame;
         this.visibility = visibility;
-        this.klass = klass;
         this.dynamicScope = dynamicScope;
         this.backtrace = backtrace;
     }
 
     private Binding(IRubyObject self, Frame frame,
-                   Visibility visibility, RubyModule klass, DynamicScope dynamicScope, BacktraceElement backtrace, DynamicScope dummyScope) {
+                    Visibility visibility, DynamicScope dynamicScope, BacktraceElement backtrace, DynamicScope dummyScope) {
         this.self = self;
         this.frame = frame;
         this.visibility = visibility;
-        this.klass = klass;
         this.dynamicScope = dynamicScope;
         this.backtrace = backtrace;
         this.dummyScope = dummyScope;
     }
 
-    public Binding(Frame frame, RubyModule bindingClass, DynamicScope dynamicScope, BacktraceElement backtrace) {
+    public Binding(Frame frame, DynamicScope dynamicScope, BacktraceElement backtrace) {
         this.self = frame.getSelf();
         this.frame = frame;
         this.visibility = frame.getVisibility();
-        this.klass = bindingClass;
         this.dynamicScope = dynamicScope;
         this.backtrace = backtrace;
     }
 
     private Binding(Binding other) {
-        this(other.self, other.frame, other.visibility, other.klass, other.dynamicScope, other.backtrace, other.dummyScope);
+        this(other.self, other.frame, other.visibility, other.dynamicScope, other.backtrace, other.dummyScope);
     }
 
     /**
@@ -179,14 +175,6 @@ public Frame getFrame() {
         return frame;
     }
 
-    /**
-     * Gets the klass.
-     * @return Returns a RubyModule
-     */
-    public RubyModule getKlass() {
-        return klass;
-    }
-
     public BacktraceElement getBacktrace() {
         return backtrace;
     }

diff --git a/core/src/main/java/org/jruby/runtime/Block.java b/core/src/main/java/org/jruby/runtime/Block.java
@@ -43,7 +43,6 @@
 
 import org.jruby.EvalType;
 import org.jruby.RubyArray;
-import org.jruby.RubyModule;
 import org.jruby.RubyProc;
 import org.jruby.runtime.builtin.IRubyObject;
 
@@ -148,20 +147,18 @@ public IRubyObject yield(ThreadContext context, IRubyObject value) {
         return body.yield(context, value, binding, type);
     }
 
-    public IRubyObject yieldNonArray(ThreadContext context, IRubyObject value, IRubyObject self,
-            RubyModule klass) {
-        return body.yield(context, new IRubyObject[] { value }, self, klass, binding, type);
+    public IRubyObject yieldNonArray(ThreadContext context, IRubyObject value, IRubyObject self) {
+        return body.yield(context, new IRubyObject[] { value }, self, binding, type);
     }
 
-    public IRubyObject yieldArray(ThreadContext context, IRubyObject value, IRubyObject self,
-            RubyModule klass) {
+    public IRubyObject yieldArray(ThreadContext context, IRubyObject value, IRubyObject self) {
         IRubyObject[] args;
         if (!(value instanceof RubyArray)) {
             args = new IRubyObject[] { value };
         } else {
             args = value.convertToArray().toJavaArray();
         }
-        return body.yield(context, args, self, klass, binding, type);
+        return body.yield(context, args, self, binding, type);
     }
 
     public Block cloneBlock() {
@@ -176,7 +173,7 @@ public Block cloneBlock() {
     public Block cloneBlockAndFrame() {
         Binding oldBinding = binding;
         Binding binding = new Binding(
-                oldBinding.getSelf(), oldBinding.getFrame().duplicate(), oldBinding.getVisibility(), oldBinding.getKlass(), oldBinding.getDynamicScope(), oldBinding.getBacktrace());
+                oldBinding.getSelf(), oldBinding.getFrame().duplicate(), oldBinding.getVisibility(), oldBinding.getDynamicScope(), oldBinding.getBacktrace());
 
         Block newBlock = new Block(body, binding);
 

diff --git a/core/src/main/java/org/jruby/runtime/BlockBody.java b/core/src/main/java/org/jruby/runtime/BlockBody.java
@@ -35,7 +35,6 @@
 
 import org.jruby.EvalType;
 import org.jruby.RubyArray;
-import org.jruby.RubyModule;
 import org.jruby.RubyProc;
 import org.jruby.ast.IterNode;
 import org.jruby.ast.MultipleAsgnNode;
@@ -69,24 +68,24 @@ public void setEvalType(EvalType evalType) {
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding, Block.Type type) {
         args = prepareArgumentsForCall(context, args, type);
 
-        return yield(context, args, null, null, binding, type);
+        return yield(context, args, null, binding, type);
     }
 
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding,
             Block.Type type, Block block) {
         args = prepareArgumentsForCall(context, args, type);
 
-        return yield(context, args, null, null, binding, type, block);
+        return yield(context, args, null, binding, type, block);
     }
 
     public final IRubyObject yield(ThreadContext context, IRubyObject value, Binding binding, Block.Type type) {
         return doYield(context, value, binding, type);
     }
 
     public final IRubyObject yield(ThreadContext context, IRubyObject[] args, IRubyObject self,
-                                   RubyModule klass, Binding binding, Block.Type type) {
+                                   Binding binding, Block.Type type) {
         IRubyObject[] preppedValue = RubyProc.prepareArgs(context, type, arity(), args);
-        return doYield(context, preppedValue, self, klass, binding, type);
+        return doYield(context, preppedValue, self, binding, type);
     }
 
     /**
@@ -100,17 +99,17 @@ public final IRubyObject yield(ThreadContext context, IRubyObject[] args, IRubyO
     /**
      * Subclass specific yield implementation.
      * <p>
-     * Should not be called directly. Gets called by {@link #yield(ThreadContext, IRubyObject[], IRubyObject, RubyModule, Binding, Block.Type)}
+     * Should not be called directly. Gets called by {@link #yield(ThreadContext, org.jruby.runtime.builtin.IRubyObject[], org.jruby.runtime.builtin.IRubyObject, Binding, org.jruby.runtime.Block.Type)}
      * after ensuring that all common yield logic is taken care of.
      */
     protected abstract IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self,
-                                           RubyModule klass, Binding binding, Block.Type type);
+                                           Binding binding, Block.Type type);
 
     // FIXME: This should be unified with the final versions above
     // Here to allow incremental replacement. Overriden by subclasses which support it.
     public IRubyObject yield(ThreadContext context, IRubyObject[] args, IRubyObject self,
-            RubyModule klass, Binding binding, Block.Type type, Block block) {
-        return yield(context, args, self, klass, binding, type);
+                             Binding binding, Block.Type type, Block block) {
+        return yield(context, args, self, binding, type);
     }
 
     // FIXME: This should be unified with the final versions above
@@ -128,7 +127,7 @@ public IRubyObject call(ThreadContext context, Binding binding, Block.Type type)
         IRubyObject[] args = IRubyObject.NULL_ARRAY;
         args = prepareArgumentsForCall(context, args, type);
 
-        return yield(context, args, null, null, binding, type);
+        return yield(context, args, null, binding, type);
     }
     public IRubyObject call(ThreadContext context, Binding binding,
             Block.Type type, Block unusedBlock) {
@@ -142,7 +141,7 @@ public IRubyObject call(ThreadContext context, IRubyObject arg0, Binding binding
         IRubyObject[] args = new IRubyObject[] {arg0};
         args = prepareArgumentsForCall(context, args, type);
 
-        return yield(context, args, null, null, binding, type);
+        return yield(context, args, null, binding, type);
     }
     public IRubyObject call(ThreadContext context, IRubyObject arg0, Binding binding,
             Block.Type type, Block unusedBlock) {
@@ -156,29 +155,29 @@ public IRubyObject call(ThreadContext context, IRubyObject arg0, IRubyObject arg
         IRubyObject[] args = new IRubyObject[] {arg0, arg1};
         args = prepareArgumentsForCall(context, args, type);
 
-        return yield(context, args, null, null, binding, type);
+        return yield(context, args, null, binding, type);
     }
     public IRubyObject call(ThreadContext context, IRubyObject arg0, IRubyObject arg1, Binding binding,
             Block.Type type, Block unusedBlock) {
         return call(context, arg0, arg1, binding, type);
     }
 
     public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, IRubyObject arg1, Binding binding, Block.Type type) {
-        return yield(context, new IRubyObject[] { arg0, arg1 }, null, null, binding, type);
+        return yield(context, new IRubyObject[] { arg0, arg1 }, null, binding, type);
     }
     public IRubyObject call(ThreadContext context, IRubyObject arg0, IRubyObject arg1, IRubyObject arg2, Binding binding, Block.Type type) {
         IRubyObject[] args = new IRubyObject[] {arg0, arg1, arg2};
         args = prepareArgumentsForCall(context, args, type);
 
-        return yield(context, args, null, null, binding, type);
+        return yield(context, args, null, binding, type);
     }
     public IRubyObject call(ThreadContext context, IRubyObject arg0, IRubyObject arg1, IRubyObject arg2, Binding binding,
             Block.Type type, Block unusedBlock) {
         return call(context, arg0, arg1, arg2, binding, type);
     }
 
     public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, IRubyObject arg1, IRubyObject arg2, Binding binding, Block.Type type) {
-        return yield(context, new IRubyObject[] { arg0, arg1, arg2 }, null, null, binding, type);
+        return yield(context, new IRubyObject[] { arg0, arg1, arg2 }, null, binding, type);
     }
 
 

diff --git a/core/src/main/java/org/jruby/runtime/CallBlock.java b/core/src/main/java/org/jruby/runtime/CallBlock.java
@@ -82,7 +82,7 @@ protected IRubyObject doYield(ThreadContext context, IRubyObject value, Binding
 
     @Override
     protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self,
-            RubyModule klass, Binding binding, Block.Type type) {
+                                  Binding binding, Block.Type type) {
         return callback.call(context, args, Block.NULL_BLOCK);
     }
 

diff --git a/core/src/main/java/org/jruby/runtime/CallBlock19.java b/core/src/main/java/org/jruby/runtime/CallBlock19.java
@@ -96,12 +96,11 @@ protected IRubyObject doYield(ThreadContext context, IRubyObject value, Binding
      * @param context represents the current thread-specific data
      * @param args The args to yield
      * @param self The current self
-     * @param klass
      * @return
      */
     @Override
     protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self,
-            RubyModule klass, Binding binding, Block.Type type) {
+                                  Binding binding, Block.Type type) {
         return callback.call(context, args, Block.NULL_BLOCK);
     }
 

diff --git a/core/src/main/java/org/jruby/runtime/CompiledBlock.java b/core/src/main/java/org/jruby/runtime/CompiledBlock.java
@@ -29,7 +29,6 @@
 
 import org.jruby.Ruby;
 import org.jruby.RubyArray;
-import org.jruby.RubyModule;
 import org.jruby.RubyProc;
 import org.jruby.ast.util.ArgsUtil;
 import org.jruby.common.IRubyWarnings.ID;
@@ -83,12 +82,12 @@ public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, Bindin
 
     @Override
     public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, IRubyObject arg1, Binding binding, Block.Type type) {
-        return yield(context, new IRubyObject[] { arg0, arg1 }, null, null, binding, type);
+        return yield(context, new IRubyObject[] { arg0, arg1 }, null, binding, type);
     }
 
     @Override
     public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, IRubyObject arg1, IRubyObject arg2, Binding binding, Block.Type type) {
-        return yield(context, new IRubyObject[] { arg0, arg1, arg2 }, null, null, binding, type);
+        return yield(context, new IRubyObject[] { arg0, arg1, arg2 }, null, binding, type);
     }
 
     @Override
@@ -97,8 +96,8 @@ protected IRubyObject doYield(ThreadContext context, IRubyObject value, Binding
     }
 
     @Override
-    protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Block.Type type) {
-        return yield(context, args, self, klass, binding, type, Block.NULL_BLOCK);
+    protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Block.Type type) {
+        return yield(context, args, self, binding, type, Block.NULL_BLOCK);
     }
 
     // FIXME: These two duplicate overrides should go away
@@ -108,7 +107,7 @@ public IRubyObject yield(ThreadContext context, IRubyObject value, Binding bindi
 
         IRubyObject realArg = setupBlockArg(context.runtime, value, self);
         Visibility oldVis = binding.getFrame().getVisibility();
-        Frame lastFrame = pre(context, null, binding);
+        Frame lastFrame = pre(context, binding);
 
         try {
             return callback.call(context, self, realArg, block);
@@ -120,16 +119,15 @@ public IRubyObject yield(ThreadContext context, IRubyObject value, Binding bindi
     }
 
     @Override
-    public IRubyObject yield(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Block.Type type, Block block) {
-        if (klass == null) {
-            self = prepareSelf(binding);
-        }
+    public IRubyObject yield(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Block.Type type, Block block) {
+        // SSS FIXME: This is now being done unconditionally compared to if (klass == null) earlier
+        self = prepareSelf(binding);
 
         IRubyObject[] preppedArgs = RubyProc.prepareArgs(context, type, arity, args);
         RubyArray value = context.runtime.newArrayNoCopyLight(preppedArgs);
         IRubyObject realArg = setupBlockArgs(context, value, self);
         Visibility oldVis = binding.getFrame().getVisibility();
-        Frame lastFrame = pre(context, klass, binding);
+        Frame lastFrame = pre(context, binding);
 
         try {
             return callback.call(context, self, realArg, block);

diff --git a/core/src/main/java/org/jruby/runtime/CompiledBlock19.java b/core/src/main/java/org/jruby/runtime/CompiledBlock19.java
@@ -28,7 +28,6 @@
 package org.jruby.runtime;
 
 import org.jruby.Ruby;
-import org.jruby.RubyModule;
 import org.jruby.RubyProc;
 import org.jruby.exceptions.JumpException;
 import org.jruby.parser.StaticScope;
@@ -80,12 +79,12 @@ public CompiledBlock19(Arity arity, StaticScope scope, CompiledBlockCallback19 c
 
     @Override
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding, Block.Type type) {
-        return yield(context, args, null, null, binding, type, Block.NULL_BLOCK);
+        return yield(context, args, null, binding, type, Block.NULL_BLOCK);
     }
 
     @Override
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding, Block.Type type, Block block) {
-        return yield(context, args, null, null, binding, type, block);
+        return yield(context, args, null, binding, type, block);
     }
 
     @Override
@@ -112,7 +111,7 @@ private IRubyObject yieldSpecificInternal(ThreadContext context, IRubyObject[] a
         IRubyObject self = prepareSelf(binding);
 
         Visibility oldVis = binding.getFrame().getVisibility();
-        Frame lastFrame = pre(context, null, binding);
+        Frame lastFrame = pre(context, binding);
 
         try {
             return callback.call(context, self, args, Block.NULL_BLOCK);
@@ -128,7 +127,7 @@ protected IRubyObject doYield(ThreadContext context, IRubyObject value, Binding
         IRubyObject self = prepareSelf(binding);
 
         Visibility oldVis = binding.getFrame().getVisibility();
-        Frame lastFrame = pre(context, null, binding);
+        Frame lastFrame = pre(context, binding);
 
         try {
             IRubyObject[] realArgs = setupBlockArg(context.runtime, value, self, type);
@@ -141,18 +140,17 @@ protected IRubyObject doYield(ThreadContext context, IRubyObject value, Binding
     }
 
     @Override
-    protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Block.Type type) {
-        return yield(context, args, self, klass, binding, type, Block.NULL_BLOCK);
+    protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Block.Type type) {
+        return yield(context, args, self, binding, type, Block.NULL_BLOCK);
     }
 
     @Override
-    public IRubyObject yield(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Block.Type type, Block block) {
-        if (klass == null) {
-            self = prepareSelf(binding);
-        }
+    public IRubyObject yield(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Block.Type type, Block block) {
+        // SSS FIXME: This is now being done unconditionally compared to if (klass == null) earlier
+        self = prepareSelf(binding);
 
         Visibility oldVis = binding.getFrame().getVisibility();
-        Frame lastFrame = pre(context, klass, binding);
+        Frame lastFrame = pre(context, binding);
 
         try {
             IRubyObject[] preppedArgs = RubyProc.prepareArgs(context, type, arity, args);

diff --git a/core/src/main/java/org/jruby/runtime/CompiledBlockLight.java b/core/src/main/java/org/jruby/runtime/CompiledBlockLight.java
@@ -27,7 +27,6 @@
  ***** END LICENSE BLOCK *****/
 package org.jruby.runtime;
 
-import org.jruby.RubyModule;
 import org.jruby.parser.StaticScope;
 import org.jruby.runtime.builtin.IRubyObject;
 
@@ -55,8 +54,8 @@ protected CompiledBlockLight(Arity arity, StaticScope scope, CompiledBlockCallba
     }
 
     @Override
-    protected Frame pre(ThreadContext context, RubyModule klass, Binding binding) {
-        return context.preYieldLightBlock(binding, binding.getDummyScope(scope), klass);
+    protected Frame pre(ThreadContext context, Binding binding) {
+        return context.preYieldLightBlock(binding, binding.getDummyScope(scope));
     }
 
     @Override

diff --git a/core/src/main/java/org/jruby/runtime/CompiledBlockLight19.java b/core/src/main/java/org/jruby/runtime/CompiledBlockLight19.java
@@ -27,7 +27,6 @@
  ***** END LICENSE BLOCK *****/
 package org.jruby.runtime;
 
-import org.jruby.RubyModule;
 import org.jruby.parser.StaticScope;
 import org.jruby.runtime.builtin.IRubyObject;
 
@@ -55,8 +54,8 @@ protected CompiledBlockLight19(Arity arity, StaticScope scope, CompiledBlockCall
     }
 
     @Override
-    protected Frame pre(ThreadContext context, RubyModule klass, Binding binding) {
-        return context.preYieldLightBlock(binding, binding.getDummyScope(scope), klass);
+    protected Frame pre(ThreadContext context, Binding binding) {
+        return context.preYieldLightBlock(binding, binding.getDummyScope(scope));
     }
 
     @Override

diff --git a/core/src/main/java/org/jruby/runtime/CompiledIRBlockBody.java b/core/src/main/java/org/jruby/runtime/CompiledIRBlockBody.java
@@ -1,12 +1,5 @@
 package org.jruby.runtime;
 
-import org.jruby.Ruby;
-import org.jruby.RubyArray;
-import org.jruby.RubyModule;
-import org.jruby.common.IRubyWarnings;
-import org.jruby.ir.IRClosure;
-import org.jruby.ir.interpreter.Interpreter;
-import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.parser.StaticScope;
 import org.jruby.runtime.Block.Type;
 import org.jruby.runtime.builtin.IRubyObject;
@@ -27,7 +20,7 @@ public CompiledIRBlockBody(StaticScope staticScope, String[] parameterList, Stri
         this.sharedScope = sharedScope;
     }
 
-    protected IRubyObject commonYieldPath(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Type type, Block block) {
+    protected IRubyObject commonYieldPath(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Type type, Block block) {
         // SSS: Important!  Use getStaticScope() to use a copy of the static-scope stored in the block-body.
         // Do not use 'closure.getStaticScope()' -- that returns the original copy of the static scope.
         // This matters because blocks created for Thread bodies modify the static-scope field of the block-body
@@ -36,8 +29,9 @@ protected IRubyObject commonYieldPath(ThreadContext context, IRubyObject[] args,
         // FIXME: Rather than modify static-scope, it seems we ought to set a field in block-body which is then
         // used to tell dynamic-scope that it is a dynamic scope for a thread body.  Anyway, to be revisited later!
         Visibility oldVis = binding.getFrame().getVisibility();
-        Frame prevFrame = context.preYieldNoScope(binding, klass);
-        if (klass == null) self = prepareSelf(binding);
+        Frame prevFrame = context.preYieldNoScope(binding);
+        // SSS FIXME: This is now being done unconditionally compared to if (klass == null) earlier
+        self = prepareSelf(binding);
         try {
             DynamicScope prevScope = binding.getDynamicScope();
             DynamicScope newScope  = sharedScope ? prevScope : DynamicScope.newDynamicScope(getStaticScope(), prevScope);

diff --git a/core/src/main/java/org/jruby/runtime/CompiledSharedScopeBlock.java b/core/src/main/java/org/jruby/runtime/CompiledSharedScopeBlock.java
@@ -27,7 +27,6 @@
  ***** END LICENSE BLOCK *****/
 package org.jruby.runtime;
 
-import org.jruby.RubyModule;
 import org.jruby.runtime.builtin.IRubyObject;
 
 /**
@@ -49,8 +48,8 @@ private CompiledSharedScopeBlock(Arity arity, DynamicScope containingScope, Comp
     }
 
     @Override
-    protected Frame pre(ThreadContext context, RubyModule klass, Binding binding) {
-        return context.preForBlock(binding, klass);
+    protected Frame pre(ThreadContext context, Binding binding) {
+        return context.preForBlock(binding);
     }
 
     @Override

diff --git a/core/src/main/java/org/jruby/runtime/ContextAwareBlockBody.java b/core/src/main/java/org/jruby/runtime/ContextAwareBlockBody.java
@@ -1,6 +1,5 @@
 package org.jruby.runtime;
 
-import org.jruby.RubyModule;
 import org.jruby.parser.StaticScope;
 
 /**
@@ -20,8 +19,8 @@ public ContextAwareBlockBody(StaticScope scope, Arity arity, int argumentType) {
         this.arity = arity;
     }
 
-    protected Frame pre(ThreadContext context, RubyModule klass, Binding binding) {
-        return context.preYieldSpecificBlock(binding, scope, klass);
+    protected Frame pre(ThreadContext context, Binding binding) {
+        return context.preYieldSpecificBlock(binding, scope);
     }
 
     protected void post(ThreadContext context, Binding binding, Visibility vis, Frame lastFrame) {

diff --git a/core/src/main/java/org/jruby/runtime/Helpers.java b/core/src/main/java/org/jruby/runtime/Helpers.java
@@ -298,14 +298,13 @@ public static IRubyObject def(ThreadContext context, IRubyObject self, Object sc
         Class compiledClass = scriptObject.getClass();
         Ruby runtime = context.runtime;
 
-        RubyModule containingClass = context.getRubyClass();
         Visibility currVisibility = context.getCurrentVisibility();
-        Visibility newVisibility = performNormalMethodChecksAndDetermineVisibility(runtime, containingClass, rubyName, currVisibility);
+        Visibility newVisibility = performNormalMethodChecksAndDetermineVisibility(runtime, null, rubyName, currVisibility);
 
         MethodFactory factory = MethodFactory.createFactory(compiledClass.getClassLoader());
         DynamicMethod method = constructNormalMethod(
                 factory, javaName,
-                rubyName, containingClass, new SimpleSourcePosition(filename, line), arity, scope, newVisibility, scriptObject,
+                rubyName, null, new SimpleSourcePosition(filename, line), arity, scope, newVisibility, scriptObject,
                 callConfig,
                 parameterDesc,
                 methodNodes);
@@ -316,7 +315,7 @@ rubyName, containingClass, new SimpleSourcePosition(filename, line), arity, scop
             ((CompiledMethod) method).unsafeSetMethodNodes(methodNodes);
         }
 
-        return addInstanceMethod(containingClass, rubyName, method, currVisibility, context, runtime);
+        return addInstanceMethod(null, rubyName, method, currVisibility, context, runtime);
     }
 
     public static IRubyObject defs(ThreadContext context, IRubyObject self, IRubyObject receiver, Object scriptObject, String rubyName, String javaName, StaticScope scope,
@@ -1639,8 +1638,7 @@ public static RubyHash constructSmallHash(Ruby runtime,
     }
 
     public static IRubyObject undefMethod(ThreadContext context, Object nameArg) {
-        RubyModule module = context.getRubyClass();
-
+        RubyModule module = null; // context.getRubyClass();
         String name = (nameArg instanceof String) ?
             (String) nameArg : nameArg.toString();
 
@@ -1655,7 +1653,7 @@ public static IRubyObject undefMethod(ThreadContext context, Object nameArg) {
 
     public static IRubyObject defineAlias(ThreadContext context, IRubyObject self, Object newNameArg, Object oldNameArg) {
         Ruby runtime = context.runtime;
-        RubyModule module = context.getRubyClass();
+        RubyModule module = null; // context.getRubyClass();
 
         if (module == null || self instanceof RubyFixnum || self instanceof RubySymbol){
             throw runtime.newTypeError("no class to make alias");

diff --git a/core/src/main/java/org/jruby/runtime/IRBlockBody.java b/core/src/main/java/org/jruby/runtime/IRBlockBody.java
@@ -3,10 +3,7 @@
 import org.jruby.EvalType;
 import org.jruby.Ruby;
 import org.jruby.RubyArray;
-import org.jruby.RubyModule;
 import org.jruby.common.IRubyWarnings.ID;
-import org.jruby.ir.IRClosure;
-import org.jruby.ir.interpreter.Interpreter;
 import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.parser.StaticScope;
 import org.jruby.runtime.Block.Type;
@@ -66,7 +63,7 @@ public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding bindi
 
     @Override
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding, Type type, Block block) {
-        return commonYieldPath(context, prepareArgumentsForCall(context, args, type), null, null, binding, type, block);
+        return commonYieldPath(context, prepareArgumentsForCall(context, args, type), null, binding, type, block);
     }
 
     @Override
@@ -75,7 +72,7 @@ public IRubyObject yieldSpecific(ThreadContext context, Binding binding, Type ty
         if (type == Type.LAMBDA) {
             arity().checkArity(context.runtime, args);
         }
-        return commonYieldPath(context, args, null, null, binding, type, Block.NULL_BLOCK);
+        return commonYieldPath(context, args, null, binding, type, Block.NULL_BLOCK);
     }
 
     @Override
@@ -89,7 +86,7 @@ public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, Bindin
             } else {
                 args = IRRuntimeHelpers.convertValueIntoArgArray(context, arg0, arity, true, true);
             }
-            return commonYieldPath(context, args, null, null, binding, type, Block.NULL_BLOCK);
+            return commonYieldPath(context, args, null, binding, type, Block.NULL_BLOCK);
         } else {
             return yield(context, arg0, binding, type);
         }
@@ -106,7 +103,7 @@ private IRubyObject yieldSpecificMultiArgsCommon(ThreadContext context, IRubyObj
                 args = new IRubyObject[] { RubyArray.newArrayNoCopy(context.runtime, args) };
             }
         }
-        return commonYieldPath(context, args, null, null, binding, type, Block.NULL_BLOCK);
+        return commonYieldPath(context, args, null, binding, type, Block.NULL_BLOCK);
     }
 
     @Override
@@ -137,26 +134,26 @@ public IRubyObject doYield(ThreadContext context, IRubyObject value, Binding bin
                 args = ((RubyArray)val0).toJavaArray();
             }
         }
-        return commonYieldPath(context, args, null, null, binding, type, Block.NULL_BLOCK);
+        return commonYieldPath(context, args, null, binding, type, Block.NULL_BLOCK);
     }
 
     @Override
-    public IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Type type) {
+    public IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Type type) {
         args = (args == null) ? IRubyObject.NULL_ARRAY : args;
         if (type == Type.LAMBDA) {
             arity().checkArity(context.runtime, args);
         }
-        return commonYieldPath(context, args, self, klass, binding, type, Block.NULL_BLOCK);
+        return commonYieldPath(context, args, self, binding, type, Block.NULL_BLOCK);
     }
 
-    protected IRubyObject prepareSelf(Binding binding) {
+    protected IRubyObject useBindingSelf(Binding binding) {
         IRubyObject self = binding.getSelf();
         binding.getFrame().setSelf(self);
 
         return self;
     }
 
-    protected abstract IRubyObject commonYieldPath(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Type type, Block block);
+    protected abstract IRubyObject commonYieldPath(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Type type, Block block);
 
     protected void blockArgWarning(Ruby ruby, int length) {
         ruby.getWarnings().warn(ID.MULTIPLE_VALUES_FOR_BLOCK, "multiple values for a block parameter (" +

diff --git a/core/src/main/java/org/jruby/runtime/Interpreted19Block.java b/core/src/main/java/org/jruby/runtime/Interpreted19Block.java
@@ -28,9 +28,7 @@
 package org.jruby.runtime;
 
 import org.jruby.Ruby;
-import org.jruby.RubyModule;
 import org.jruby.RubyProc;
-import org.jruby.ast.ArgsNoArgNode;
 import org.jruby.ast.ArgsNode;
 import org.jruby.ast.IterNode;
 import org.jruby.ast.LambdaNode;
@@ -117,12 +115,12 @@ public Interpreted19Block(LambdaNode lambdaNode) {
 
     @Override
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding, Block.Type type) {
-        return yield(context, args, null, null, binding, type, Block.NULL_BLOCK);
+        return yield(context, args, null, binding, type, Block.NULL_BLOCK);
     }
 
     @Override
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding, Block.Type type, Block block) {
-        return yield(context, args, null, null, binding, type, block);
+        return yield(context, args, null, binding, type, block);
     }
 
     @Override
@@ -137,20 +135,20 @@ public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, Bindin
 
     @Override
     public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, IRubyObject arg1, Binding binding, Block.Type type) {
-        return yield(context, new IRubyObject[] { arg0, arg1 }, null, null, binding, type);
+        return yield(context, new IRubyObject[] { arg0, arg1 }, null, binding, type);
     }
 
     @Override
     public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, IRubyObject arg1, IRubyObject arg2, Binding binding, Block.Type type) {
-        return yield(context, new IRubyObject[] { arg0, arg1, arg2 }, null, null, binding, type);
+        return yield(context, new IRubyObject[] { arg0, arg1, arg2 }, null, binding, type);
     }
 
     @Override
     protected IRubyObject doYield(ThreadContext context, IRubyObject value, Binding binding, Block.Type type) {
         IRubyObject self = prepareSelf(binding);
 
         Visibility oldVis = binding.getFrame().getVisibility();
-        Frame lastFrame = pre(context, null, binding);
+        Frame lastFrame = pre(context, binding);
 
         try {
             setupBlockArg(context, value, self, Block.NULL_BLOCK, type);
@@ -169,25 +167,23 @@ protected IRubyObject doYield(ThreadContext context, IRubyObject value, Binding
      * @param context represents the current thread-specific data
      * @param args The args for yield
      * @param self The current self
-     * @param klass
      * @return
      */
     @Override
     protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self,
-            RubyModule klass, Binding binding, Block.Type type) {
-        return yield(context, args, self, klass, binding, type, Block.NULL_BLOCK);
+                                  Binding binding, Block.Type type) {
+        return yield(context, args, self, binding, type, Block.NULL_BLOCK);
 
     }
 
     @Override
     public IRubyObject yield(ThreadContext context, IRubyObject[] args, IRubyObject self,
-            RubyModule klass, Binding binding, Block.Type type, Block block) {
-        if (klass == null) {
-            self = prepareSelf(binding);
-        }
+                             Binding binding, Block.Type type, Block block) {
+        // SSS FIXME: This is now being done unconditionally compared to if (klass == null) earlier
+        self = prepareSelf(binding);
 
         Visibility oldVis = binding.getFrame().getVisibility();
-        Frame lastFrame = pre(context, klass, binding);
+        Frame lastFrame = pre(context, binding);
 
         try {
             IRubyObject[] preppedArgs = RubyProc.prepareArgs(context, type, arity, args);

diff --git a/core/src/main/java/org/jruby/runtime/InterpretedIRBlockBody.java b/core/src/main/java/org/jruby/runtime/InterpretedIRBlockBody.java
@@ -7,7 +7,6 @@
 import org.jruby.runtime.ThreadContext;
 import org.jruby.ir.IRClosure;
 import org.jruby.ir.interpreter.Interpreter;
-import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.runtime.Block.Type;
 import org.jruby.runtime.builtin.IRubyObject;
 
@@ -19,7 +18,7 @@ public InterpretedIRBlockBody(IRClosure closure, Arity arity, int argumentType)
         this.closure = closure;
     }
 
-    protected IRubyObject commonYieldPath(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Type type, Block block) {
+    protected IRubyObject commonYieldPath(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Type type, Block block) {
         // SSS: Important!  Use getStaticScope() to use a copy of the static-scope stored in the block-body.
         // Do not use 'closure.getStaticScope()' -- that returns the original copy of the static scope.
         // This matters because blocks created for Thread bodies modify the static-scope field of the block-body
@@ -28,8 +27,12 @@ protected IRubyObject commonYieldPath(ThreadContext context, IRubyObject[] args,
         // FIXME: Rather than modify static-scope, it seems we ought to set a field in block-body which is then
         // used to tell dynamic-scope that it is a dynamic scope for a thread body.  Anyway, to be revisited later!
         Visibility oldVis = binding.getFrame().getVisibility();
-        Frame prevFrame = context.preYieldNoScope(binding, klass);
-        if (klass == null) self = prepareSelf(binding);
+        Frame prevFrame = context.preYieldNoScope(binding);
+
+        // SSS FIXME: Why is self null in non-binding-eval contexts?
+        if (self == null || this.evalType == EvalType.BINDING_EVAL) {
+            self = useBindingSelf(binding);
+        }
         DynamicScope newScope = null;
         try {
             DynamicScope prevScope = binding.getDynamicScope();

diff --git a/core/src/main/java/org/jruby/runtime/JavaInternalBlockBody.java b/core/src/main/java/org/jruby/runtime/JavaInternalBlockBody.java
@@ -5,7 +5,6 @@
 package org.jruby.runtime;
 
 import org.jruby.Ruby;
-import org.jruby.RubyModule;
 import org.jruby.parser.StaticScope;
 import org.jruby.runtime.Block.Type;
 import org.jruby.runtime.builtin.IRubyObject;
@@ -49,13 +48,13 @@ private void threadCheck(ThreadContext yieldingContext) {
 
     @Override
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding, Block.Type type) {
-        return yield(context, args, null, null, binding, type);
+        return yield(context, args, null, binding, type);
     }
 
     @Override
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding,
                             Block.Type type, Block block) {
-        return yield(context, args, null, null, binding, type, block);
+        return yield(context, args, null, binding, type, block);
     }
 
     @Override
@@ -66,7 +65,7 @@ protected IRubyObject doYield(ThreadContext context, IRubyObject value, Binding
     }
 
     @Override
-    protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Type type) {
+    protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Type type) {
         threadCheck(context);
 
         return yield(context, args);

diff --git a/core/src/main/java/org/jruby/runtime/MethodBlock.java b/core/src/main/java/org/jruby/runtime/MethodBlock.java
@@ -59,7 +59,6 @@ public static Block createMethodBlock(ThreadContext context, IRubyObject self, D
 
         Binding binding = new Binding(
                 frame,
-                module,
                 dynamicScope,
                 new BacktraceElement(method.getMethodName(), body.getFile(), body.getLine()));
 
@@ -80,17 +79,17 @@ public MethodBlock(RubyMethod method, StaticScope staticScope) {
 
     @Override
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding, Block.Type type) {
-        return yield(context, args, null, null, binding, type, Block.NULL_BLOCK);
+        return yield(context, args, null, binding, type, Block.NULL_BLOCK);
     }
 
     @Override
     public IRubyObject call(ThreadContext context, IRubyObject[] args, Binding binding, Block.Type type, Block block) {
-        return yield(context, args, null, null, binding, type, block);
+        return yield(context, args, null, binding, type, block);
     }
 
     @Override
-    protected Frame pre(ThreadContext context, RubyModule klass, Binding binding) {
-        return context.preYieldNoScope(binding, klass);
+    protected Frame pre(ThreadContext context, Binding binding) {
+        return context.preYieldNoScope(binding);
     }
 
     @Override
@@ -110,12 +109,12 @@ public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, Bindin
 
     @Override
     public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, IRubyObject arg1, Binding binding, Block.Type type) {
-        return yield(context, new IRubyObject[] { arg0, arg1 }, null, null, binding, type);
+        return yield(context, new IRubyObject[] { arg0, arg1 }, null, binding, type);
     }
 
     @Override
     public IRubyObject yieldSpecific(ThreadContext context, IRubyObject arg0, IRubyObject arg1, IRubyObject arg2, Binding binding, Block.Type type) {
-        return yield(context, new IRubyObject[] { arg0, arg1, arg2 }, null, null, binding, type);
+        return yield(context, new IRubyObject[] { arg0, arg1, arg2 }, null, binding, type);
     }
 
     @Override
@@ -130,8 +129,15 @@ public IRubyObject yield(ThreadContext context, IRubyObject value, Binding bindi
 
     @Override
     protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self,
-                             RubyModule klass, Binding binding, Block.Type type) {
-        return yield(context, args, self, klass, binding, type, Block.NULL_BLOCK);
+                                  Binding binding, Block.Type type) {
+        return yield(context, args, self, binding, type, Block.NULL_BLOCK);
+    }
+
+    protected IRubyObject prepareSelf(Binding binding) {
+        IRubyObject self = binding.getSelf();
+        binding.getFrame().setSelf(self);
+
+        return self;
     }
 
     /**
@@ -140,18 +146,15 @@ protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyOb
      * @param context represents the current thread-specific data
      * @param args The args for yield
      * @param self The current self
-     * @param klass
      * @return
      */
     @Override
     public IRubyObject yield(ThreadContext context, IRubyObject[] args, IRubyObject self,
-            RubyModule klass, Binding binding, Block.Type type, Block block) {
-        if (klass == null) {
-            self = binding.getSelf();
-            binding.getFrame().setSelf(self);
-        }
+                             Binding binding, Block.Type type, Block block) {
+        // SSS FIXME: This is now being done unconditionally compared to if (klass == null) earlier
+        self = prepareSelf(binding);
 
-        Frame lastFrame = pre(context, klass, binding);
+        Frame lastFrame = pre(context, binding);
 
         try {
             // This while loop is for restarting the block call in case a 'redo' fires.

diff --git a/core/src/main/java/org/jruby/runtime/NullBlockBody.java b/core/src/main/java/org/jruby/runtime/NullBlockBody.java
@@ -1,7 +1,6 @@
 package org.jruby.runtime;
 
 import org.jruby.RubyLocalJumpError;
-import org.jruby.RubyModule;
 import org.jruby.parser.StaticScope;
 import org.jruby.runtime.Block.Type;
 import org.jruby.runtime.builtin.IRubyObject;
@@ -55,7 +54,7 @@ protected IRubyObject doYield(ThreadContext context, IRubyObject value, Binding
     }
 
     @Override
-    protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, RubyModule klass, Binding binding, Type type) {
+    protected IRubyObject doYield(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Type type) {
         throw context.runtime.newLocalJumpError(RubyLocalJumpError.Reason.NOREASON, args[0], "yield called out of block");
     }
 

diff --git a/core/src/main/java/org/jruby/runtime/ThreadContext.java b/core/src/main/java/org/jruby/runtime/ThreadContext.java
@@ -50,7 +50,6 @@
 import org.jruby.ir.IRScopeType;
 import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.lexer.yacc.ISourcePosition;
-import org.jruby.parser.IRStaticScope;
 import org.jruby.parser.StaticScope;
 import org.jruby.parser.IRStaticScope;
 import org.jruby.runtime.backtrace.BacktraceElement;
@@ -103,10 +102,7 @@ public static ThreadContext newContext(Ruby runtime) {
     private ThreadFiber rootFiber; // hard anchor for root threads' fibers
     // Cache format string because it is expensive to create on demand
     private RubyDateFormatter dateFormatter;
-
-    private RubyModule[] parentStack = new RubyModule[INITIAL_SIZE];
-    private int parentIndex = -1;
-
+
     private Frame[] frameStack = new Frame[INITIAL_FRAMES_SIZE];
     private int frameIndex = -1;
 
@@ -286,16 +282,7 @@ private Frame[] fillNewFrameStack(Frame[] newFrameStack, int newSize) {
 
         return newFrameStack;
     }
-
-    private void expandParentStack() {
-        int newSize = parentStack.length * 2;
-        RubyModule[] newParentStack = new RubyModule[newSize];
 
-        System.arraycopy(parentStack, 0, newParentStack, 0, parentStack.length);
-
-        parentStack = newParentStack;
-    }
-
     public void pushScope(DynamicScope scope) {
         int index = ++scopeIndex;
         DynamicScope[] stack = scopeStack;
@@ -681,41 +668,6 @@ public void trace(RubyEvent event, String name, RubyModule implClass) {
     public void trace(RubyEvent event, String name, RubyModule implClass, String file, int line) {
         runtime.callEventHooks(this, event, file, line, name, implClass);
     }
-
-    public void pushRubyClass(RubyModule currentModule) {
-        // FIXME: this seems like a good assertion, but it breaks compiled code and the code seems
-        // to run without it...
-        //assert currentModule != null : "Can't push null RubyClass";
-        // int index = ++parentIndex;
-        // RubyModule[] stack = parentStack;
-        // stack[index] = currentModule;
-        // if (index + 1 == stack.length) {
-        //     expandParentStack();
-        // }
-    }
-
-    public RubyModule popRubyClass() {
-        // int index = parentIndex;
-        // RubyModule[] stack = parentStack;
-        // RubyModule ret = stack[index];
-        // stack[index] = null;
-        // parentIndex = index - 1;
-        // return ret;
-        return null;
-    }
-
-    public RubyModule getRubyClass() {
-        // assert parentIndex != -1 : "Trying to get RubyClass from empty stack";
-        // RubyModule parentModule = parentStack[parentIndex];
-        // return parentModule.getNonIncludedClass();
-        return null;
-    }
-
-    public RubyModule getPreviousRubyClass() {
-        assert parentIndex != 0 : "Trying to getService RubyClass from too-shallow stack";
-        RubyModule parentModule = parentStack[parentIndex - 1];
-        return parentModule.getNonIncludedClass();
-    }
 
     @Deprecated
     public boolean getConstantDefined(String internedName) {
@@ -969,24 +921,20 @@ private Frame pushFrameForEval(Binding binding) {
 
     public void preAdoptThread() {
         pushFrame();
-        pushRubyClass(runtime.getObject());
         getCurrentFrame().setSelf(runtime.getTopSelf());
     }
 
     public void preExtensionLoad(IRubyObject self) {
         pushFrame();
-        pushRubyClass(runtime.getObject());
         getCurrentFrame().setSelf(self);
         getCurrentFrame().setVisibility(Visibility.PUBLIC);
     }
 
     public void postExtensionLoad() {
         popFrame();
-        popRubyClass();
     }
 
     public void preCompiledClass(RubyModule type, StaticScope staticScope) {
-        pushRubyClass(type);
         pushFrameCopy();
         getCurrentFrame().setSelf(type);
         getCurrentFrame().setVisibility(Visibility.PUBLIC);
@@ -995,7 +943,6 @@ public void preCompiledClass(RubyModule type, StaticScope staticScope) {
     }
 
     public void preCompiledClassDummyScope(RubyModule type, StaticScope staticScope) {
-        pushRubyClass(type);
         pushFrameCopy();
         getCurrentFrame().setSelf(type);
         getCurrentFrame().setVisibility(Visibility.PUBLIC);
@@ -1005,7 +952,6 @@ public void preCompiledClassDummyScope(RubyModule type, StaticScope staticScope)
 
     public void postCompiledClass() {
         popScope();
-        popRubyClass();
         popFrame();
     }
 
@@ -1018,7 +964,6 @@ public void postScopeNode() {
     }
 
     public void preClassEval(StaticScope staticScope, RubyModule type) {
-        pushRubyClass(type);
         pushFrameCopy();
         getCurrentFrame().setSelf(type);
         getCurrentFrame().setVisibility(Visibility.PUBLIC);
@@ -1029,7 +974,6 @@ public void preClassEval(StaticScope staticScope, RubyModule type) {
 
     public void postClassEval() {
         popScope();
-        popRubyClass();
         popFrame();
     }
 
@@ -1048,14 +992,12 @@ public void preMethodFrameAndClass(RubyModule implClass, String name, IRubyObjec
         RubyModule ssModule = staticScope.getModule();
         // FIXME: This is currently only here because of some problems with IOOutputStream writing to a "bare" runtime without a proper scope
         if (ssModule == null) ssModule = implClass;
-        pushRubyClass(ssModule);
         pushCallFrame(implClass, name, self, block);
     }
 
     // FIXME: This may not be correct for RubyClass in all cases
     public void preMethodFrameAndClass(String name, IRubyObject self, Block block, StaticScope staticScope) {
         RubyModule ssModule = staticScope.getModule();
-        pushRubyClass(ssModule);
         pushCallFrame(ssModule, name, self, block);
     }
 
@@ -1068,7 +1010,6 @@ public void preMethodFrameAndScope(RubyModule clazz, String name, IRubyObject se
         }
         pushCallFrame(clazz, name, self, block);
         pushScope(DynamicScope.newDynamicScope(staticScope));
-        pushRubyClass(implementationClass);
     }
 
     public void preMethodFrameAndDummyScope(RubyModule clazz, String name, IRubyObject self, Block block, 
@@ -1080,7 +1021,6 @@ public void preMethodFrameAndDummyScope(RubyModule clazz, String name, IRubyObje
         }
         pushCallFrame(clazz, name, self, block);
         pushScope(staticScope.getDummyScope());
-        pushRubyClass(implementationClass);
     }
 
     public void preMethodNoFrameAndDummyScope(RubyModule clazz, StaticScope staticScope) {
@@ -1090,23 +1030,19 @@ public void preMethodNoFrameAndDummyScope(RubyModule clazz, StaticScope staticSc
             implementationClass = clazz;
         }
         pushScope(staticScope.getDummyScope());
-        pushRubyClass(implementationClass);
     }
 
     public void postMethodFrameAndScope() {
-        popRubyClass();
         popScope();
         popFrame();
     }
 
     public void preMethodFrameOnly(RubyModule clazz, String name, IRubyObject self, Block block) {
-        pushRubyClass(clazz);
         pushCallFrame(clazz, name, self, block);
     }
 
     public void postMethodFrameOnly() {
         popFrame();
-        popRubyClass();
     }
 
     public void preMethodScopeOnly(RubyModule clazz, StaticScope staticScope) {
@@ -1116,11 +1052,9 @@ public void preMethodScopeOnly(RubyModule clazz, StaticScope staticScope) {
             implementationClass = clazz;
         }
         pushScope(DynamicScope.newDynamicScope(staticScope));
-        pushRubyClass(implementationClass);
     }
 
     public void postMethodScopeOnly() {
-        popRubyClass();
         popScope();
     }
 
@@ -1142,49 +1076,40 @@ public void preMethodBacktraceDummyScope(RubyModule clazz, String name, StaticSc
             implementationClass = clazz;
         }
         pushScope(staticScope.getDummyScope());
-        pushRubyClass(implementationClass);
     }
 
     public void postMethodBacktraceOnly() {
     }
 
     public void postMethodBacktraceDummyScope() {
-        popRubyClass();
         popScope();
     }
 
     public void prepareTopLevel(RubyClass objectClass, IRubyObject topSelf) {
         pushFrame();
         setCurrentVisibility(Visibility.PRIVATE);
-
-        pushRubyClass(objectClass);
-
         Frame frame = getCurrentFrame();
         frame.setSelf(topSelf);
 
         getCurrentScope().getStaticScope().setModule(objectClass);
     }
 
     public void preNodeEval(RubyModule rubyClass, IRubyObject self, String name) {
-        pushRubyClass(rubyClass);
         pushEvalFrame(self);
     }
 
     public void preNodeEval(RubyModule rubyClass, IRubyObject self) {
-        pushRubyClass(rubyClass);
         pushEvalFrame(self);
     }
 
     public void postNodeEval() {
         popFrame();
-        popRubyClass();
     }
 
     // XXX: Again, screwy evaling under previous frame's scope
     public void preExecuteUnder(RubyModule executeUnderClass, Block block) {
         Frame frame = getCurrentFrame();
 
-        pushRubyClass(executeUnderClass);
         DynamicScope scope = getCurrentScope();
         StaticScope sScope = runtime.getStaticScopeFactory().newBlockScope(scope.getStaticScope());
         sScope.setModule(executeUnderClass);
@@ -1196,7 +1121,6 @@ public void preExecuteUnder(RubyModule executeUnderClass, Block block) {
     public void postExecuteUnder() {
         popFrame();
         popScope();
-        popRubyClass();
     }
 
     public void preMproc() {
@@ -1217,28 +1141,27 @@ public void postTrace() {
         setWithinTrace(false);
     }
 
-    public Frame preForBlock(Binding binding, RubyModule klass) {
-        Frame lastFrame = preYieldNoScope(binding, klass);
+    public Frame preForBlock(Binding binding) {
+        Frame lastFrame = preYieldNoScope(binding);
         pushScope(binding.getDynamicScope());
         return lastFrame;
     }
 
-    public Frame preYieldSpecificBlock(Binding binding, StaticScope scope, RubyModule klass) {
-        Frame lastFrame = preYieldNoScope(binding, klass);
+    public Frame preYieldSpecificBlock(Binding binding, StaticScope scope) {
+        Frame lastFrame = preYieldNoScope(binding);
         // new scope for this invocation of the block, based on parent scope
         pushScope(DynamicScope.newDynamicScope(scope, binding.getDynamicScope()));
         return lastFrame;
     }
 
-    public Frame preYieldLightBlock(Binding binding, DynamicScope emptyScope, RubyModule klass) {
-        Frame lastFrame = preYieldNoScope(binding, klass);
+    public Frame preYieldLightBlock(Binding binding, DynamicScope emptyScope) {
+        Frame lastFrame = preYieldNoScope(binding);
         // just push the same empty scope, since we won't use one
         pushScope(emptyScope);
         return lastFrame;
     }
 
-    public Frame preYieldNoScope(Binding binding, RubyModule klass) {
-        pushRubyClass((klass != null) ? klass : binding.getKlass());
+    public Frame preYieldNoScope(Binding binding) {
         return pushFrameForBlock(binding);
     }
 
@@ -1252,30 +1175,25 @@ public void postEvalScriptlet() {
 
     public Frame preEvalWithBinding(Binding binding) {
         Frame lastFrame = pushFrameForEval(binding);
-        pushRubyClass(binding.getKlass());
         return lastFrame;
     }
 
     public void postEvalWithBinding(Binding binding, Frame lastFrame) {
         popFrameReal(lastFrame);
-        popRubyClass();
     }
 
     public void postYield(Binding binding, Frame lastFrame) {
         popScope();
         popFrameReal(lastFrame);
-        popRubyClass();
     }
 
     public void postYieldLight(Binding binding, Frame lastFrame) {
         popScope();
         popFrameReal(lastFrame);
-        popRubyClass();
     }
 
     public void postYieldNoScope(Frame lastFrame) {
         popFrameReal(lastFrame);
-        popRubyClass();
     }
 
     public void preScopedBody(DynamicScope scope) {
@@ -1312,7 +1230,7 @@ public void setWithinTrace(boolean isWithinTrace) {
      */
     public Binding currentBinding() {
         Frame frame = getCurrentFrame().capture();
-        return new Binding(frame, parentIndex < 0 ? frame.getKlazz() : getRubyClass(), getCurrentScope(), backtrace[backtraceIndex].clone());
+        return new Binding(frame, getCurrentScope(), backtrace[backtraceIndex].clone());
     }
 
     /**
@@ -1322,7 +1240,7 @@ public Binding currentBinding() {
      */
     public Binding currentBinding(IRubyObject self) {
         Frame frame = getCurrentFrame().capture();
-        return new Binding(self, frame, frame.getVisibility(), getRubyClass(), getCurrentScope(), backtrace[backtraceIndex].clone());
+        return new Binding(self, frame, frame.getVisibility(), getCurrentScope(), backtrace[backtraceIndex].clone());
     }
 
     /**
@@ -1334,7 +1252,7 @@ public Binding currentBinding(IRubyObject self) {
      */
     public Binding currentBinding(IRubyObject self, Visibility visibility) {
         Frame frame = getCurrentFrame().capture();
-        return new Binding(self, frame, visibility, getRubyClass(), getCurrentScope(), backtrace[backtraceIndex].clone());
+        return new Binding(self, frame, visibility, getCurrentScope(), backtrace[backtraceIndex].clone());
     }
 
     /**
@@ -1346,7 +1264,7 @@ public Binding currentBinding(IRubyObject self, Visibility visibility) {
      */
     public Binding currentBinding(IRubyObject self, DynamicScope scope) {
         Frame frame = getCurrentFrame().capture();
-        return new Binding(self, frame, frame.getVisibility(), getRubyClass(), scope, backtrace[backtraceIndex].clone());
+        return new Binding(self, frame, frame.getVisibility(), scope, backtrace[backtraceIndex].clone());
     }
 
     /**
@@ -1361,7 +1279,7 @@ public Binding currentBinding(IRubyObject self, DynamicScope scope) {
      */
     public Binding currentBinding(IRubyObject self, Visibility visibility, DynamicScope scope) {
         Frame frame = getCurrentFrame().capture();
-        return new Binding(self, frame, visibility, getRubyClass(), scope, backtrace[backtraceIndex].clone());
+        return new Binding(self, frame, visibility, scope, backtrace[backtraceIndex].clone());
     }
 
     /**
@@ -1371,7 +1289,7 @@ public Binding currentBinding(IRubyObject self, Visibility visibility, DynamicSc
     @Deprecated
     public Binding previousBinding() {
         Frame frame = getPreviousFrame();
-        return new Binding(frame, getPreviousRubyClass(), getCurrentScope(), backtrace[backtraceIndex].clone());
+        return new Binding(frame, getCurrentScope(), backtrace[backtraceIndex].clone());
     }
 
     /**
@@ -1382,7 +1300,7 @@ public Binding previousBinding() {
     @Deprecated
     public Binding previousBinding(IRubyObject self) {
         Frame frame = getPreviousFrame();
-        return new Binding(self, frame, frame.getVisibility(), getPreviousRubyClass(), getCurrentScope(), backtrace[backtraceIndex].clone());
+        return new Binding(self, frame, frame.getVisibility(), getCurrentScope(), backtrace[backtraceIndex].clone());
     }
 
     /**