Merge branch 'master' into truffle-head

Conflicts: truffle/src/main/java/org/jruby/truffle/nodes/core/BindingNodes.java
jruby · May 9, 2015 · 08193c6 · 08193c6
2 parents bd54763 + 60600db
commit 08193c6
Showing 104 changed files with 1,128 additions and 2,427 deletions.
diff --git a/.gitignore b/.gitignore
@@ -105,3 +105,6 @@ build.eclipse
 truffle-findbugs-report.html
 findbugs-noUpdateChecks-3.0.0.tar.gz
 findbugs-3.0.0
+
+# Vagrant
+/.vagrant
diff --git a/antlib/extra.xml b/antlib/extra.xml
@@ -112,7 +112,6 @@ build jruby-complete.jar
 <arg value='test/test_irubyobject_java_passing.rb'/>
 <arg value='test/test_jruby_object_input_stream.rb'/>
 <arg value='test/test_jar_on_load_path.rb'/>
-<arg value='test/test_jruby_ext.rb'/>
 <arg value='test/test_jruby_core_ext.rb'/>
 <arg value='test/test_thread_context_frame_dereferences_unreachable_variables.rb'/>
 <arg value='test/test_context_classloader.rb'/>

diff --git a/core/src/main/java/org/jruby/AbstractRubyMethod.java b/core/src/main/java/org/jruby/AbstractRubyMethod.java
@@ -31,23 +31,13 @@
  ***** END LICENSE BLOCK *****/
 package org.jruby;
 
-import org.jruby.anno.JRubyClass;
 import org.jruby.anno.JRubyMethod;
-import org.jruby.ext.jruby.JRubyLibrary;
 import org.jruby.internal.runtime.methods.DynamicMethod;
 import org.jruby.internal.runtime.methods.IRMethodArgs;
-import org.jruby.internal.runtime.methods.ProcMethod;
 import org.jruby.internal.runtime.methods.UndefinedMethod;
-import org.jruby.runtime.Block;
-import org.jruby.runtime.BlockBody;
-import org.jruby.runtime.ClassIndex;
-import org.jruby.runtime.CompiledBlockCallback19;
-import org.jruby.runtime.CompiledBlockLight19;
 import org.jruby.runtime.Helpers;
-import org.jruby.runtime.ObjectAllocator;
 import org.jruby.runtime.PositionAware;
 import org.jruby.runtime.ThreadContext;
-import org.jruby.runtime.Visibility;
 import org.jruby.runtime.builtin.IRubyObject;
 import org.jruby.runtime.marshal.DataType;
 
@@ -145,7 +135,7 @@ public int getLine() {
 
     @JRubyMethod(name = "parameters")
     public IRubyObject parameters(ThreadContext context) {
-        return JRubyLibrary.MethodExtensions.methodArgs(this);
+        return Helpers.methodToParameters(context.runtime, this);
     }
 
     protected IRubyObject super_method(ThreadContext context, IRubyObject receiver, RubyModule superClass) {

diff --git a/core/src/main/java/org/jruby/Ruby.java b/core/src/main/java/org/jruby/Ruby.java
@@ -112,7 +112,6 @@
 import org.jruby.runtime.Binding;
 import org.jruby.runtime.Block;
 import org.jruby.runtime.CallSite;
-import org.jruby.runtime.CallbackFactory;
 import org.jruby.runtime.ClassIndex;
 import org.jruby.runtime.DynamicScope;
 import org.jruby.runtime.EventHook;
@@ -4804,15 +4803,6 @@ private void addEvalParseToStats() {
         if (parserStats != null) parserStats.addEvalParse();
     }
 
-    private void addJRubyModuleParseToStats() {
-        if (parserStats != null) parserStats.addJRubyModuleParse();
-    }
-
-    @Deprecated
-    public CallbackFactory callbackFactory(Class<?> type) {
-        throw new RuntimeException("callback-style handles are no longer supported in JRuby");
-    }
-
     @Deprecated
     public boolean is1_8() {
         return false;

diff --git a/core/src/main/java/org/jruby/RubyArray.java b/core/src/main/java/org/jruby/RubyArray.java
@@ -559,7 +559,7 @@ private IRubyObject initializeCommon(ThreadContext context, IRubyObject arg0, IR
                 runtime.getWarnings().warn(ID.BLOCK_BEATS_DEFAULT_VALUE, "block supersedes default value argument");
             }
 
-            if (block.getBody().getArgumentType() == BlockBody.ZERO_ARGS) {
+            if (block.getSignature() == Signature.NO_ARGUMENTS) {
                 IRubyObject nil = runtime.getNil();
                 for (int i = 0; i < ilen; i++) {
                     store(i, block.yield(context, nil));

diff --git a/core/src/main/java/org/jruby/RubyFixnum.java b/core/src/main/java/org/jruby/RubyFixnum.java
@@ -286,8 +286,7 @@ public IRubyObject times(ThreadContext context, Block block) {
             long lvalue = this.value;
             boolean checkArity = block.type.checkArity;
 
-            if (block.getBody().getArgumentType() == BlockBody.ZERO_ARGS ||
-                    block.getSignature() == Signature.NO_ARGUMENTS) {
+            if (block.getSignature() == Signature.NO_ARGUMENTS) {
                 if (checkArity) {
                     // must pass arg
                     IRubyObject nil = runtime.getNil();

diff --git a/core/src/main/java/org/jruby/RubyInteger.java b/core/src/main/java/org/jruby/RubyInteger.java
@@ -44,6 +44,7 @@
 import org.jruby.runtime.BlockBody;
 import org.jruby.runtime.ClassIndex;
 import org.jruby.runtime.ObjectAllocator;
+import org.jruby.runtime.Signature;
 import org.jruby.runtime.ThreadContext;
 import org.jruby.runtime.builtin.IRubyObject;
 import org.jruby.util.ByteList;
@@ -141,7 +142,7 @@ public IRubyObject upto(ThreadContext context, IRubyObject to, Block block) {
     private static void fixnumUpto(ThreadContext context, long from, long to, Block block) {
         // We must avoid "i++" integer overflow when (to == Long.MAX_VALUE).
         Ruby runtime = context.runtime;
-        if (block.getBody().getArgumentType() == BlockBody.ZERO_ARGS) {
+        if (block.getSignature() == Signature.NO_ARGUMENTS) {
             IRubyObject nil = runtime.getNil();
             long i;
             for (i = from; i < to; i++) {
@@ -204,7 +205,7 @@ public IRubyObject downto(ThreadContext context, IRubyObject to, Block block) {
     private static void fixnumDownto(ThreadContext context, long from, long to, Block block) {
         // We must avoid "i--" integer overflow when (to == Long.MIN_VALUE).
         Ruby runtime = context.runtime;
-        if (block.getBody().getArgumentType() == BlockBody.ZERO_ARGS) {
+        if (block.getSignature() == Signature.NO_ARGUMENTS) {
             IRubyObject nil = runtime.getNil();
             long i;
             for (i = from; i > to; i--) {

diff --git a/core/src/main/java/org/jruby/RubyMethod.java b/core/src/main/java/org/jruby/RubyMethod.java
@@ -31,26 +31,21 @@
  ***** END LICENSE BLOCK *****/
 package org.jruby;
 
-import org.jruby.ext.jruby.JRubyLibrary;
 import org.jruby.anno.JRubyMethod;
 import org.jruby.anno.JRubyClass;
 import org.jruby.internal.runtime.methods.AliasMethod;
 import org.jruby.internal.runtime.methods.DynamicMethod;
 import org.jruby.internal.runtime.methods.IRMethodArgs;
 import org.jruby.internal.runtime.methods.ProcMethod;
-import org.jruby.runtime.Arity;
+import org.jruby.runtime.ArgumentDescriptor;
 import org.jruby.runtime.Block;
-import org.jruby.runtime.BlockBody;
 import org.jruby.runtime.ClassIndex;
-import org.jruby.runtime.CompiledBlockCallback19;
-import org.jruby.runtime.CompiledBlockLight;
-import org.jruby.runtime.CompiledBlockLight19;
 import org.jruby.runtime.Helpers;
+import org.jruby.runtime.MethodBlockBody;
 import org.jruby.runtime.ObjectAllocator;
 import org.jruby.runtime.PositionAware;
 import org.jruby.runtime.Signature;
 import org.jruby.runtime.ThreadContext;
-import org.jruby.runtime.Visibility;
 import org.jruby.runtime.builtin.IRubyObject;
 
 /** 
@@ -188,48 +183,26 @@ public RubyMethod rbClone() {
      * 
      */
     @JRubyMethod
-    public IRubyObject to_proc(ThreadContext context, Block unusedBlock) {
+    public IRubyObject to_proc(ThreadContext context) {
         Ruby runtime = context.runtime;
-        CompiledBlockCallback19 callback = new CompiledBlockCallback19() {
-            @Override
-            public IRubyObject call(ThreadContext context, IRubyObject self, IRubyObject[] args, Block block) {
-                return method.call(context, receiver, originModule, originName, args, block);
-            }
-
-            @Override
-            public String getFile() {
-                return getFilename();
-            }
-
-            @Override
-            public int getLine() {
-                return RubyMethod.this.getLine();
-            }
-        };
 
-        BlockBody body;
+        MethodBlockBody body;
+        Signature signature;
+        ArgumentDescriptor[] argsDesc;
         if (method instanceof IRMethodArgs) {
-            Signature signature = ((IRMethodArgs) method).getSignature();
-            int argumentType = resolveArgumentType(signature.isFixed(), signature.required());
-            body = CompiledBlockLight19.newCompiledBlockLight(((IRMethodArgs) method).getSignature(),
-                    runtime.getStaticScopeFactory().getDummyScope(), callback, false, argumentType, JRubyLibrary.MethodExtensions.methodParameters(runtime, method));
+            signature = ((IRMethodArgs) method).getSignature();
+            argsDesc = ((IRMethodArgs) method).getArgumentDescriptors();
         } else {
-            Arity arity = method.getArity();
-            int argumentType = resolveArgumentType(arity.isFixed(), arity.required());
-            body = CompiledBlockLight19.newCompiledBlockLight(method.getArity(),
-                    runtime.getStaticScopeFactory().getDummyScope(), callback, false, argumentType, JRubyLibrary.MethodExtensions.methodParameters(runtime, method));
+            signature = Signature.from(method.getArity());
+            argsDesc = Helpers.methodToArgumentDescriptors(method);
         }
-        Block b = new Block(body, context.currentBinding(receiver, Visibility.PUBLIC));
+
+        body = new MethodBlockBody(runtime.getStaticScopeFactory().getDummyScope(), signature, method, argsDesc, receiver, originModule, originName, getFilename(), getLine());
+        Block b = MethodBlockBody.createMethodBlock(body);
 
         return RubyProc.newProc(runtime, b, Block.Type.LAMBDA);
     }
 
-    private int resolveArgumentType(boolean isFixed, int required) {
-        if (!isFixed) return BlockBody.MULTIPLE_ASSIGNMENT;
-        if (required > 0) return BlockBody.MULTIPLE_ASSIGNMENT;
-        return BlockBody.ZERO_ARGS;
-    }
-
     @JRubyMethod
     public RubyUnboundMethod unbind() {
         RubyUnboundMethod unboundMethod =
@@ -316,12 +289,12 @@ public int getLine() {
 
     @JRubyMethod
     public IRubyObject parameters(ThreadContext context) {
-        return JRubyLibrary.MethodExtensions.methodArgs(this);
+        return Helpers.methodToParameters(context.runtime, this);
     }
 
     @JRubyMethod(optional = 1)
     public IRubyObject curry(ThreadContext context, IRubyObject[] args) {
-        return to_proc(context, Block.NULL_BLOCK).callMethod(context, "curry", args);
+        return to_proc(context).callMethod(context, "curry", args);
     }
 
     @JRubyMethod
@@ -337,5 +310,6 @@ public IRubyObject original_name(ThreadContext context) {
         }
         return name(context);
     }
+
 }
 
diff --git a/core/src/main/java/org/jruby/RubyProc.java b/core/src/main/java/org/jruby/RubyProc.java
@@ -45,7 +45,6 @@
 import org.jruby.runtime.ClassIndex;
 import org.jruby.runtime.Helpers;
 import org.jruby.runtime.IRBlockBody;
-import org.jruby.runtime.MethodBlock;
 import org.jruby.runtime.ObjectAllocator;
 import org.jruby.runtime.Signature;
 import org.jruby.runtime.ThreadContext;
@@ -241,9 +240,6 @@ public IRubyObject call(ThreadContext context, IRubyObject[] args) {
     public static IRubyObject[] prepareArgs(ThreadContext context, Block.Type type, BlockBody blockBody, IRubyObject[] args) {
         Signature signature = blockBody.getSignature();
 
-        // FIXME: which blocks have no signature (and no arity before that?)
-        if (signature == null) return args;
-
         if (args == null) return IRubyObject.NULL_ARRAY;
 
         if (type == Block.Type.LAMBDA) {
@@ -349,10 +345,8 @@ public IRubyObject source_location(ThreadContext context) {
     public IRubyObject parameters(ThreadContext context) {
         BlockBody body = this.getBlock().getBody();
 
-        if (body instanceof MethodBlock) return ((MethodBlock) body).getMethod().parameters(context);
-
-        return Helpers.parameterListToParameters(context.runtime,
-                body.getParameterList(), isLambda());
+        return Helpers.argumentDescriptorsToParameters(context.runtime,
+                body.getArgumentDescriptors(), isLambda());
     }
 
     @JRubyMethod(name = "lambda?")

diff --git a/core/src/main/java/org/jruby/RubyRange.java b/core/src/main/java/org/jruby/RubyRange.java
@@ -421,7 +421,7 @@ private void fixnumEach(ThreadContext context, Ruby runtime, Block block) {
             to--;
         }
         long from = ((RubyFixnum) begin).getLongValue();
-        if (block.getBody().getArgumentType() == BlockBody.ZERO_ARGS) {
+        if (block.getSignature() == Signature.NO_ARGUMENTS) {
             IRubyObject nil = runtime.getNil();
             long i;
             for (i = from; i < to; i++) {

diff --git a/core/src/main/java/org/jruby/RubySymbol.java b/core/src/main/java/org/jruby/RubySymbol.java
@@ -282,7 +282,13 @@ public IRubyObject id2name(ThreadContext context) {
     @JRubyMethod(name = "===", required = 1)
     @Override
     public IRubyObject op_eqq(ThreadContext context, IRubyObject other) {
-        return super.op_equal(context, other);
+        return context.runtime.newBoolean(this == other);
+    }
+
+    @JRubyMethod(name = "==", required = 1)
+    @Override
+    public IRubyObject op_equal(ThreadContext context, IRubyObject other) {
+        return context.runtime.newBoolean(this == other);
     }
 
     @Deprecated
@@ -419,7 +425,7 @@ public IRubyObject encoding(ThreadContext context) {
     public IRubyObject to_proc(ThreadContext context) {
         StaticScope scope = context.runtime.getStaticScopeFactory().getDummyScope();
         final CallSite site = new FunctionalCachingCallSite(symbol);
-        BlockBody body = new ContextAwareBlockBody(scope, Signature.OPTIONAL, BlockBody.SINGLE_RESTARG) {
+        BlockBody body = new ContextAwareBlockBody(scope, Signature.OPTIONAL) {
             private IRubyObject yieldInner(ThreadContext context, RubyArray array, Block block) {
                 if (array.isEmpty()) {
                     throw context.runtime.newArgumentError("no receiver given");

diff --git a/core/src/main/java/org/jruby/ast/executable/AbstractScript.java b/core/src/main/java/org/jruby/ast/executable/AbstractScript.java
@@ -5,10 +5,8 @@
 
 package org.jruby.ast.executable;
 
-import java.math.BigInteger;
 import org.jcodings.Encoding;
 import org.jcodings.EncodingDB;
-import org.jruby.Ruby;
 import org.jruby.RubyFixnum;
 import org.jruby.RubyFloat;
 import org.jruby.RubyModule;
@@ -18,14 +16,14 @@
 import org.jruby.internal.runtime.methods.DynamicMethod;
 import org.jruby.parser.StaticScope;
 import org.jruby.runtime.Block;
-import org.jruby.runtime.BlockBody;
-import org.jruby.runtime.CompiledBlockCallback;
 import org.jruby.runtime.CallSite;
 import org.jruby.runtime.MethodIndex;
 import org.jruby.runtime.ThreadContext;
 import org.jruby.runtime.builtin.IRubyObject;
 import org.jruby.util.ByteList;
 
+import java.math.BigInteger;
+
 /**
  *
  * @author headius
@@ -105,46 +103,6 @@ public IRubyObject run(ThreadContext context, IRubyObject self, IRubyObject[] ar
     public final CallSite getCallSite8() {return runtimeCache.callSites[8];}
     public final CallSite getCallSite9() {return runtimeCache.callSites[9];}
 
-    public static final int NUMBERED_BLOCKBODY_COUNT = 10;
-
-    public final BlockBody getBlockBody(ThreadContext context, StaticScope scope, int i, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, i, descriptor);}
-    public final BlockBody getBlockBody0(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, 0, descriptor);}
-    public final BlockBody getBlockBody1(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, 1, descriptor);}
-    public final BlockBody getBlockBody2(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, 2, descriptor);}
-    public final BlockBody getBlockBody3(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, 3, descriptor);}
-    public final BlockBody getBlockBody4(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, 4, descriptor);}
-    public final BlockBody getBlockBody5(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, 5, descriptor);}
-    public final BlockBody getBlockBody6(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, 6, descriptor);}
-    public final BlockBody getBlockBody7(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, 7, descriptor);}
-    public final BlockBody getBlockBody8(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, 8, descriptor);}
-    public final BlockBody getBlockBody9(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody(this, context, scope, 9, descriptor);}
-
-    public final BlockBody getBlockBody19(ThreadContext context, StaticScope scope, int i, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, i, descriptor);}
-    public final BlockBody getBlockBody190(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, 0, descriptor);}
-    public final BlockBody getBlockBody191(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, 1, descriptor);}
-    public final BlockBody getBlockBody192(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, 2, descriptor);}
-    public final BlockBody getBlockBody193(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, 3, descriptor);}
-    public final BlockBody getBlockBody194(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, 4, descriptor);}
-    public final BlockBody getBlockBody195(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, 5, descriptor);}
-    public final BlockBody getBlockBody196(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, 6, descriptor);}
-    public final BlockBody getBlockBody197(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, 7, descriptor);}
-    public final BlockBody getBlockBody198(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, 8, descriptor);}
-    public final BlockBody getBlockBody199(ThreadContext context, StaticScope scope, String descriptor) {return runtimeCache.getBlockBody19(this, context, scope, 9, descriptor);}
-
-    public static final int NUMBERED_BLOCKCALLBACK_COUNT = 10;
-
-    public final CompiledBlockCallback getBlockCallback(int i, String method) {return runtimeCache.getBlockCallback(this, i, method);}
-    public final CompiledBlockCallback getBlockCallback0(String method) {return runtimeCache.getBlockCallback(this, 0, method);}
-    public final CompiledBlockCallback getBlockCallback1(String method) {return runtimeCache.getBlockCallback(this, 1, method);}
-    public final CompiledBlockCallback getBlockCallback2(String method) {return runtimeCache.getBlockCallback(this, 2, method);}
-    public final CompiledBlockCallback getBlockCallback3(String method) {return runtimeCache.getBlockCallback(this, 3, method);}
-    public final CompiledBlockCallback getBlockCallback4(String method) {return runtimeCache.getBlockCallback(this, 4, method);}
-    public final CompiledBlockCallback getBlockCallback5(String method) {return runtimeCache.getBlockCallback(this, 5, method);}
-    public final CompiledBlockCallback getBlockCallback6(String method) {return runtimeCache.getBlockCallback(this, 6, method);}
-    public final CompiledBlockCallback getBlockCallback7(String method) {return runtimeCache.getBlockCallback(this, 7, method);}
-    public final CompiledBlockCallback getBlockCallback8(String method) {return runtimeCache.getBlockCallback(this, 8, method);}
-    public final CompiledBlockCallback getBlockCallback9(String method) {return runtimeCache.getBlockCallback(this, 9, method);}
-
     public static final int NUMBERED_SYMBOL_COUNT = 10;
 
     public final RubySymbol getSymbol(ThreadContext context, int i, String name, String encoding) {return runtimeCache.getSymbol(context, i, name, encoding);}

diff --git a/core/src/main/java/org/jruby/ast/executable/RuntimeCache.java b/core/src/main/java/org/jruby/ast/executable/RuntimeCache.java
@@ -19,10 +19,8 @@
 import org.jruby.internal.runtime.methods.UndefinedMethod;
 import org.jruby.runtime.Helpers;
 import org.jruby.parser.StaticScope;
-import org.jruby.runtime.BlockBody;
 import org.jruby.runtime.CallSite;
 import org.jruby.runtime.CallType;
-import org.jruby.runtime.CompiledBlockCallback;
 import org.jruby.runtime.MethodIndex;
 import org.jruby.runtime.ThreadContext;
 import org.jruby.runtime.builtin.IRubyObject;
@@ -53,50 +51,6 @@ public final CallSite getCallSite(int index) {
         return callSites[index];
     }
 
-    /**
-     * descriptor format is
-     *
-     * closure_method_name,arity,varname1;varname2;varname3,has_multi_args_head,arg_type,light
-     *
-     * @param context
-     * @param index
-     * @param descriptor
-     * @return
-     */
-    public final BlockBody getBlockBody(Object scriptObject, ThreadContext context, StaticScope scope, int index, String descriptor) {
-        BlockBody body = blockBodies[index];
-        if (body == null) {
-            return createBlockBody(scriptObject, context, scope, index, descriptor);
-        }
-        return body;
-    }
-
-    /**
-     * descriptor format is
-     *
-     * closure_method_name,arity,varname1;varname2;varname3,has_multi_args_head,arg_type,light
-     *
-     * @param context
-     * @param index
-     * @param descriptor
-     * @return
-     */
-    public final BlockBody getBlockBody19(Object scriptObject, ThreadContext context, StaticScope scope, int index, String descriptor) {
-        BlockBody body = blockBodies[index];
-        if (body == null) {
-            return createBlockBody19(scriptObject, context, scope, index, descriptor);
-        }
-        return body;
-    }
-
-    public final CompiledBlockCallback getBlockCallback(Object scriptObject, int index, String method) {
-        CompiledBlockCallback callback = blockCallbacks[index];
-        if (callback == null) {
-            return createCompiledBlockCallback(scriptObject, index, method);
-        }
-        return callback;
-    }
-
     public final RubySymbol getSymbol(ThreadContext context, int index, String name, String encodingName) {
         RubySymbol symbol = symbols[index];
         if (symbol == null) {
@@ -288,9 +242,7 @@ public final void initFromDescriptor(String descriptor) {
     private static final int BIGINTEGER = REGEXP + 1;
     private static final int VARIABLEREADER = BIGINTEGER + 1;
     private static final int VARIABLEWRITER = VARIABLEREADER + 1;
-    private static final int BLOCKBODY = VARIABLEWRITER + 1;
-    private static final int BLOCKCALLBACK = BLOCKBODY + 1;
-    private static final int METHOD = BLOCKCALLBACK + 1;
+    private static final int METHOD = VARIABLEWRITER + 1;
     private static final int STRING = METHOD + 1;
     private static final int ENCODING = STRING + 1;
     private static final int FROZEN_STRING = ENCODING + 1;
@@ -335,10 +287,6 @@ public final void initFromDescriptor(String descriptor) {
         if (variableReaderCount > 0) initVariableReaders(variableReaderCount);
         int variableWriterCount = getDescriptorValue(descriptor, VARIABLEWRITER);
         if (variableWriterCount > 0) initVariableWriters(variableWriterCount);
-        int blockBodyCount = getDescriptorValue(descriptor, BLOCKBODY);
-        if (blockBodyCount > 0) initBlockBodies(blockBodyCount);
-        int blockCallbackCount = getDescriptorValue(descriptor, BLOCKCALLBACK);
-        if (blockCallbackCount > 0) initBlockCallbacks(blockCallbackCount);
         int methodCount = getDescriptorValue(descriptor, METHOD);
         if (methodCount > 0) initMethodCache(methodCount);
         int stringCount = getDescriptorValue(descriptor, STRING);
@@ -353,14 +301,6 @@ private static int getDescriptorValue(String descriptor, int type) {
         return descriptor.charAt(type);
     }
 
-    public final void initBlockBodies(int size) {
-        blockBodies = new BlockBody[size];
-    }
-
-    public final void initBlockCallbacks(int size) {
-        blockCallbacks = new CompiledBlockCallback[size];
-    }
-
     public final void initSymbols(int size) {
         symbols = new RubySymbol[size];
     }
@@ -463,21 +403,6 @@ public IRubyObject reCacheFrom(RubyModule target, ThreadContext context, String
         return value;
     }
 
-    private BlockBody createBlockBody(Object scriptObject, ThreadContext context, StaticScope scope, int index, String descriptor) throws NumberFormatException {
-        BlockBody body = Helpers.createCompiledBlockBody(context, scriptObject, scope, descriptor);
-        return blockBodies[index] = body;
-    }
-
-    private BlockBody createBlockBody19(Object scriptObject, ThreadContext context, StaticScope scope, int index, String descriptor) throws NumberFormatException {
-        BlockBody body = Helpers.createCompiledBlockBody19(context, scriptObject, scope, descriptor);
-        return blockBodies[index] = body;
-    }
-
-    private CompiledBlockCallback createCompiledBlockCallback(Object scriptObject, int index, String method) {
-        CompiledBlockCallback callback = Helpers.createBlockCallback(scriptObject, method, "(internal)", -1);
-        return blockCallbacks[index] = callback;
-    }
-
     public DynamicMethod getMethod(ThreadContext context, RubyClass selfType, int index, String methodName) {
         CacheEntry myCache = getCacheEntry(index);
         if (CacheEntry.typeOk(myCache, selfType)) {
@@ -660,10 +585,6 @@ private CacheEntry getCacheEntry(int index) {
     public CallSite[] callSites = EMPTY_CALLSITES;
     private static final CacheEntry[] EMPTY_CACHEENTRIES = {};
     public CacheEntry[] methodCache = EMPTY_CACHEENTRIES;
-    private static final BlockBody[] EMPTY_BLOCKBODIES = {};
-    public BlockBody[] blockBodies = EMPTY_BLOCKBODIES;
-    private static final CompiledBlockCallback[] EMPTY_COMPILEDBLOCKCALLBACKS = {};
-    public CompiledBlockCallback[] blockCallbacks = EMPTY_COMPILEDBLOCKCALLBACKS;
     private static final RubySymbol[] EMPTY_RUBYSYMBOLS = {};
     public RubySymbol[] symbols = EMPTY_RUBYSYMBOLS;
     private static final ByteList[] EMPTY_BYTELISTS = {};

diff --git a/core/src/main/java/org/jruby/embed/jsr223/JRubyScriptEngineManager.java b/core/src/main/java/org/jruby/embed/jsr223/JRubyScriptEngineManager.java
@@ -122,7 +122,7 @@ public Object get(String key) {
 
     public ScriptEngine getEngineByName(String shortName) {
         if (shortName == null) {
-            throw new NullPointerException("Null shortName");
+            throw new NullPointerException("Null symbolicName");
         }
         ScriptEngineFactory factory = nameMap.get(shortName);
         if (factory == null) {

diff --git a/core/src/main/java/org/jruby/ext/jruby/JRubyLibrary.java b/core/src/main/java/org/jruby/ext/jruby/JRubyLibrary.java
@@ -30,23 +30,17 @@
  ***** END LICENSE BLOCK *****/
 package org.jruby.ext.jruby;
 
-import java.util.ArrayList;
 import org.jruby.AbstractRubyMethod;
 import org.jruby.Ruby;
-import org.jruby.RubyArray;
 import org.jruby.RubyClass;
 import org.jruby.RubyModule;
-import org.jruby.RubySymbol;
 import org.jruby.anno.JRubyMethod;
 import org.jruby.anno.JRubyModule;
 import org.jruby.internal.runtime.methods.DynamicMethod;
-import org.jruby.internal.runtime.methods.IRMethodArgs;
-import org.jruby.internal.runtime.methods.MethodArgs2;
 import org.jruby.java.proxies.JavaProxy;
 import org.jruby.javasupport.Java;
 import org.jruby.javasupport.JavaObject;
 import org.jruby.javasupport.JavaUtil;
-import org.jruby.runtime.Arity;
 import org.jruby.runtime.Helpers;
 import org.jruby.runtime.ThreadContext;
 import org.jruby.runtime.builtin.IRubyObject;
@@ -150,64 +144,6 @@ public static IRubyObject identity_hash(ThreadContext context, IRubyObject recv,
     }
 
     public static class MethodExtensions {
-        @JRubyMethod(name = "args")
-        public static IRubyObject methodArgs(IRubyObject recv) {
-            Ruby runtime = recv.getRuntime();
-            AbstractRubyMethod rubyMethod = (AbstractRubyMethod)recv;
-            RubyArray argsArray = RubyArray.newArray(runtime);
-            DynamicMethod method = rubyMethod.getMethod().getRealMethod();
-            RubySymbol rest = runtime.newSymbol("rest");
-
-            if (method instanceof MethodArgs2) {
-                return Helpers.parameterListToParameters(runtime, ((MethodArgs2) method).getParameterList(), true);
-            } else if (method instanceof IRMethodArgs) {
-                String[] argsDesc = ((IRMethodArgs) method).getParameterList();
-
-                for (int i = 0; i < argsDesc.length; i++) {
-                    RubySymbol argType = runtime.newSymbol(argsDesc[i]);
-                    i++;
-                    String argName = argsDesc[i];
-                    if (argName.isEmpty()) {
-                        argsArray.append(RubyArray.newArray(runtime, argType));
-                    } else {
-                        argsArray.append(RubyArray.newArray(runtime, argType, runtime.newSymbol(argName)));
-                    }
-                }
-            } else {
-                if (method.getArity() == Arity.OPTIONAL) {
-                    argsArray.append(RubyArray.newArray(runtime, rest));
-                }
-            }
-
-            return argsArray;
-        }
-
-        public static String[] methodParameters(Ruby runtime, DynamicMethod method) {
-            ArrayList<String> argsArray = new ArrayList<String>();
-            method = method.getRealMethod();
-
-            if (method instanceof MethodArgs2) {
-                return ((MethodArgs2) method).getParameterList();
-            } else if (method instanceof IRMethodArgs) {
-                String[] argsDesc = ((IRMethodArgs) method).getParameterList();
-
-                for (int i = 0; i < argsDesc.length; i++) {
-                    String argType = argsDesc[i];
-                    i++;
-                    String argName = argsDesc[i];
-                    if (argName.isEmpty()) {
-                        argsArray.add(argType);
-                    } else {
-                        argsArray.add(argType + argName);
-                    }
-                }
-            } else {
-                if (method.getArity() == Arity.OPTIONAL) {
-                    argsArray.add("r");
-                }
-            }
-
-            return argsArray.toArray(new String[argsArray.size()]);
-        }
+
     }
 }
diff --git a/core/src/main/java/org/jruby/ext/socket/RubySocket.java b/core/src/main/java/org/jruby/ext/socket/RubySocket.java
@@ -313,7 +313,7 @@ public static IRubyObject gethostbyname(ThreadContext context, IRubyObject recv,
         return SocketUtils.gethostbyname(context, hostname);
     }
 
-    @JRubyMethod(required = 2, optional = 4, meta = true)
+    @JRubyMethod(required = 2, optional = 5, meta = true)
     public static IRubyObject getaddrinfo(ThreadContext context, IRubyObject recv, IRubyObject[] args) {
         return SocketUtils.getaddrinfo(context, args);
     }

diff --git a/core/src/main/java/org/jruby/ext/socket/SocketUtils.java b/core/src/main/java/org/jruby/ext/socket/SocketUtils.java
@@ -32,6 +32,7 @@
 import jnr.netdb.Service;
 import org.jruby.Ruby;
 import org.jruby.RubyArray;
+import org.jruby.RubyBoolean;
 import org.jruby.RubyClass;
 import org.jruby.RubyFixnum;
 import org.jruby.RubyInteger;
@@ -182,15 +183,15 @@ public static IRubyObject gethostbyname(ThreadContext context, IRubyObject hostn
     /**
      * Ruby definition would look like:
      *
-     * def self.getaddrinfo(host, port, family = nil, socktype = nil, protocol = nil, flags = nil)
+     * def self.getaddrinfo(host, port, family = nil, socktype = nil, protocol = nil, flags = nil, reverse_lookup = nil)
      */
     public static IRubyObject getaddrinfo(final ThreadContext context, IRubyObject[] args) {
         final Ruby runtime = context.runtime;
         final List<IRubyObject> l = new ArrayList<IRubyObject>();
 
         buildAddrinfoList(context, args, new AddrinfoCallback() {
             @Override
-            public void addrinfo(InetAddress address, int port, Sock sock) {
+            public void addrinfo(InetAddress address, int port, Sock sock, Boolean reverse) {
                 boolean is_ipv6 = address instanceof Inet6Address;
                 boolean sock_stream = true;
                 boolean sock_dgram = true;
@@ -211,7 +212,7 @@ public void addrinfo(InetAddress address, int port, Sock sock) {
                     c = new IRubyObject[7];
                     c[0] = runtime.newString(is_ipv6 ? "AF_INET6" : "AF_INET");
                     c[1] = runtime.newFixnum(port);
-                    c[2] = runtime.newString(getHostAddress(context, address));
+                    c[2] = runtime.newString(getHostAddress(context, address, reverse));
                     c[3] = runtime.newString(address.getHostAddress());
                     c[4] = runtime.newFixnum(is_ipv6 ? PF_INET6 : PF_INET);
                     c[5] = runtime.newFixnum(SOCK_DGRAM);
@@ -223,7 +224,7 @@ public void addrinfo(InetAddress address, int port, Sock sock) {
                     c = new IRubyObject[7];
                     c[0] = runtime.newString(is_ipv6 ? "AF_INET6" : "AF_INET");
                     c[1] = runtime.newFixnum(port);
-                    c[2] = runtime.newString(getHostAddress(context, address));
+                    c[2] = runtime.newString(getHostAddress(context, address, reverse));
                     c[3] = runtime.newString(address.getHostAddress());
                     c[4] = runtime.newFixnum(is_ipv6 ? PF_INET6 : PF_INET);
                     c[5] = runtime.newFixnum(SOCK_STREAM);
@@ -242,7 +243,7 @@ public static List<Addrinfo> getaddrinfoList(ThreadContext context, IRubyObject[
 
         buildAddrinfoList(context, args, new AddrinfoCallback() {
             @Override
-            public void addrinfo(InetAddress address, int port, Sock sock) {
+            public void addrinfo(InetAddress address, int port, Sock sock, Boolean reverse) {
                 boolean sock_stream = true;
                 boolean sock_dgram = true;
 
@@ -279,7 +280,8 @@ interface AddrinfoCallback {
         void addrinfo(
                 InetAddress address,
                 int port,
-                Sock sock);
+                Sock sock,
+                Boolean reverse);
     }
 
     public static void buildAddrinfoList(ThreadContext context, IRubyObject[] args, AddrinfoCallback callback) {
@@ -297,6 +299,24 @@ public static void buildAddrinfoList(ThreadContext context, IRubyObject[] args,
             IRubyObject socktype = args.length > 3 ? args[3] : context.nil;
             //IRubyObject protocol = args[4];
             IRubyObject flags = args.length > 5 ? args[5] : context.nil;
+            IRubyObject reverseArg = args.length > 6 ? args[6] : context.nil;
+
+            // The Ruby Socket.getaddrinfo function supports boolean/nil/Symbol values for the
+            // reverse_lookup parameter. We need to massage all valid inputs to true/false/null.
+            Boolean reverseLookup = null;
+            if (reverseArg instanceof RubyBoolean) {
+                reverseLookup = reverseArg.isTrue();
+            } else if (reverseArg instanceof RubySymbol) {
+                String reverseString = reverseArg.toString();
+                if ("hostname".equals(reverseString)) {
+                    reverseLookup = true;
+                } else if ("numeric".equals(reverseString)) {
+                    reverseLookup = false;
+                } else {
+                    throw runtime.newArgumentError("invalid reverse_lookup flag: :" + 
+                     reverseString);
+                }
+            }
 
             AddressFamily addressFamily = AF_INET;
             if (!family.isNil()) {
@@ -339,7 +359,7 @@ public static void buildAddrinfoList(ThreadContext context, IRubyObject[] args,
 
             for(int i = 0; i < addrs.length; i++) {
                 int p = port.isNil() ? 0 : (int)port.convertToInteger().getLongValue();
-                callback.addrinfo(addrs[i], p, sock);
+                callback.addrinfo(addrs[i], p, sock, reverseLookup);
             }
 
         } catch(UnknownHostException e) {
@@ -527,8 +547,21 @@ public static int getPortFrom(ThreadContext context, IRubyObject _port) {
         return port;
     }
 
+    private static String getHostAddress(ThreadContext context, InetAddress addr, Boolean reverse) {
+        String ret;
+        if (reverse == null) {
+            ret = context.runtime.isDoNotReverseLookupEnabled() ? 
+                   addr.getHostAddress() : addr.getCanonicalHostName();
+        } else if (reverse) {
+            ret = addr.getCanonicalHostName();
+        } else {
+            ret = addr.getHostAddress();
+        }
+        return ret;
+    }
+
     private static String getHostAddress(ThreadContext context, InetAddress addr) {
-        return context.runtime.isDoNotReverseLookupEnabled() ? addr.getHostAddress() : addr.getCanonicalHostName();
+        return getHostAddress(context, addr, null);
     }
 
     private static final Pattern STRING_IPV4_ADDRESS_PATTERN =

diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/CompiledIRMetaClassBody.java b/core/src/main/java/org/jruby/internal/runtime/methods/CompiledIRMetaClassBody.java
@@ -4,6 +4,7 @@
 import org.jruby.ir.IRFlags;
 import org.jruby.ir.IRScope;
 import org.jruby.parser.StaticScope;
+import org.jruby.runtime.ArgumentDescriptor;
 import org.jruby.runtime.Block;
 import org.jruby.runtime.DynamicScope;
 import org.jruby.runtime.ThreadContext;
@@ -24,8 +25,8 @@ public CompiledIRMetaClassBody(MethodHandle handle, IRScope scope, RubyModule im
         this.popDynScope = this.pushNewDynScope || reuseParentDynScope;
     }
 
-    public String[] getParameterList() {
-        return new String[0];
+    public ArgumentDescriptor[] getArgumentDescriptors() {
+        return new ArgumentDescriptor[0];
     }
 
     @Override

diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/CompiledIRMethod.java b/core/src/main/java/org/jruby/internal/runtime/methods/CompiledIRMethod.java
@@ -5,6 +5,7 @@
 import org.jruby.ir.IRScope;
 import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.parser.StaticScope;
+import org.jruby.runtime.ArgumentDescriptor;
 import org.jruby.runtime.Arity;
 import org.jruby.runtime.Block;
 import org.jruby.runtime.PositionAware;
@@ -17,14 +18,13 @@
 
 import org.jruby.runtime.Helpers;
 
-public class CompiledIRMethod extends JavaMethod implements IRMethodArgs, MethodArgs2, PositionAware {
+public class CompiledIRMethod extends DynamicMethod implements IRMethodArgs, PositionAware {
     protected final MethodHandle variable;
 
     protected final MethodHandle specific;
     protected final int specificArity;
 
     protected final IRScope method;
-    private String[] parameterList;
     private final StaticScope staticScope;
     private final boolean hasExplicitCallProtocol;
     private final boolean hasKwargs;
@@ -72,10 +72,8 @@ public Signature getSignature() {
         return staticScope.getSignature();
     }
 
-    public String[] getParameterList() {
-        if (parameterList != null) return parameterList;
-
-        return parameterList = Helpers.irMethodArgsToParameters(((IRMethod)method).getArgDesc());
+    public ArgumentDescriptor[] getArgumentDescriptors() {
+        return ((IRMethod)method).getArgumentDescriptors();
     }
 
     @Override

diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/IRMethodArgs.java b/core/src/main/java/org/jruby/internal/runtime/methods/IRMethodArgs.java
@@ -1,13 +1,22 @@
 package org.jruby.internal.runtime.methods;
 
+import org.jruby.runtime.ArgumentDescriptor;
 import org.jruby.runtime.Signature;
 
+/**
+ * Represents a method object that can return a Signature and an array of ArgumentDescriptors.
+ */
 public interface IRMethodArgs {
     // FIXME: Should get pushed to DynamicMethod
+
+    /**
+     * Get the Signature for this method.
+     */
     public Signature getSignature();
-    public String[] getParameterList();
 
-    public enum ArgType {
-        key, keyreq, keyrest, block, opt, rest, req
-    }
+    /**
+     * Get the array of ArgumentDescriptors that represent the arguments to this method.
+     */
+    public ArgumentDescriptor[] getArgumentDescriptors();
+
 }
diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/InterpretedIRBodyMethod.java b/core/src/main/java/org/jruby/internal/runtime/methods/InterpretedIRBodyMethod.java
@@ -4,6 +4,7 @@
 import org.jruby.ir.IRScope;
 import org.jruby.ir.interpreter.InterpreterContext;
 import org.jruby.ir.runtime.IRRuntimeHelpers;
+import org.jruby.runtime.ArgumentDescriptor;
 import org.jruby.runtime.Block;
 import org.jruby.runtime.ThreadContext;
 import org.jruby.runtime.Visibility;
@@ -20,8 +21,8 @@ public InterpretedIRBodyMethod(IRScope method, RubyModule implementationClass) {
     }
 
     @Override
-    public String[] getParameterList() {
-        return new String[0];
+    public ArgumentDescriptor[] getArgumentDescriptors() {
+        return ArgumentDescriptor.EMPTY_ARRAY;
     }
 
     @Override

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
@@ -8,6 +8,7 @@
 import org.jruby.ir.interpreter.InterpreterContext;
 import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.parser.StaticScope;
+import org.jruby.runtime.ArgumentDescriptor;
 import org.jruby.runtime.Arity;
 import org.jruby.runtime.Block;
 import org.jruby.runtime.DynamicScope;
@@ -55,9 +56,9 @@ public StaticScope getStaticScope() {
         return method.getStaticScope();
     }
 
-    public String[] getParameterList() {
+    public ArgumentDescriptor[] getArgumentDescriptors() {
         ensureInstrsReady(); // Make sure method is minimally built before returning this info
-        return ((IRMethod) method).getArgDesc();
+        return ((IRMethod) method).getArgumentDescriptors();
     }
 
     public Signature getSignature() {

diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/InvocationMethodFactory.java b/core/src/main/java/org/jruby/internal/runtime/methods/InvocationMethodFactory.java
@@ -28,20 +28,9 @@
  ***** END LICENSE BLOCK *****/
 package org.jruby.internal.runtime.methods;
 
-import java.io.PrintWriter;
-import java.lang.reflect.Modifier;
-import java.util.Arrays;
-import java.util.List;
-
 import org.jruby.Ruby;
 import org.jruby.RubyInstanceConfig;
 import org.jruby.RubyKernel;
-import org.jruby.parser.StaticScope;
-import org.jruby.runtime.Helpers;
-import org.jruby.runtime.Signature;
-import org.jruby.util.ClassDefiningClassLoader;
-import org.objectweb.asm.ClassWriter;
-import org.objectweb.asm.Opcodes;
 import org.jruby.RubyModule;
 import org.jruby.RubyString;
 import org.jruby.anno.JRubyMethod;
@@ -51,23 +40,35 @@
 import org.jruby.exceptions.JumpException;
 import org.jruby.exceptions.RaiseException;
 import org.jruby.lexer.yacc.ISourcePosition;
+import org.jruby.parser.StaticScope;
 import org.jruby.runtime.Arity;
 import org.jruby.runtime.Block;
-import org.jruby.runtime.CompiledBlockCallback;
-import org.jruby.runtime.CompiledBlockCallback19;
+import org.jruby.runtime.Helpers;
 import org.jruby.runtime.MethodFactory;
+import org.jruby.runtime.Signature;
 import org.jruby.runtime.ThreadContext;
 import org.jruby.runtime.Visibility;
 import org.jruby.runtime.builtin.IRubyObject;
-import org.jruby.util.CodegenUtils;
-import static org.jruby.util.CodegenUtils.*;
-import static java.lang.System.*;
 import org.jruby.util.ClassDefiningJRubyClassLoader;
+import org.jruby.util.CodegenUtils;
+import org.jruby.util.log.Logger;
+import org.jruby.util.log.LoggerFactory;
 import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassWriter;
 import org.objectweb.asm.Label;
+import org.objectweb.asm.Opcodes;
 import org.objectweb.asm.util.CheckClassAdapter;
-import org.jruby.util.log.Logger;
-import org.jruby.util.log.LoggerFactory;
+
+import java.io.PrintWriter;
+import java.lang.reflect.Modifier;
+import java.util.Arrays;
+import java.util.List;
+
+import static java.lang.System.out;
+import static org.jruby.util.CodegenUtils.ci;
+import static org.jruby.util.CodegenUtils.p;
+import static org.jruby.util.CodegenUtils.params;
+import static org.jruby.util.CodegenUtils.sig;
 
 /**
  * In order to avoid the overhead with reflection-based method handles, this
@@ -93,18 +94,6 @@ public class InvocationMethodFactory extends MethodFactory implements Opcodes {
 
     /** The pathname of the super class for compiled Ruby method handles. */ 
     private final static String COMPILED_SUPER_CLASS_NAME = p(COMPILED_SUPER_CLASS);
-
-    /** The class used for the super class of compiled Ruby block handles. */
-    private static final Class<CompiledBlockCallback> COMPILED_BLOCK_SUPER_CLASS = CompiledBlockCallback.class;
-
-    /** The pathname of the super class for compiled Ruby block handles. */
-    private static final String COMPILED_BLOCK_SUPER_CLASS_NAME = p(COMPILED_BLOCK_SUPER_CLASS);
-
-    /** The interface used for compiled Ruby 1.9+ block handles. */
-    public static final Class<CompiledBlockCallback19> COMPILED_BLOCK_19_INTERFACE = CompiledBlockCallback19.class;
-
-    /** The pathname of the interface for compiled Ruby block handles. */
-    public static final String COMPILED_BLOCK_19_INTERFACE_NAME = p(COMPILED_BLOCK_19_INTERFACE);
 
     /** The outward call signature for compiled Ruby method handles. */
     private final static String COMPILED_CALL_SIG = sig(IRubyObject.class,
@@ -935,180 +924,6 @@ public static String getBlockCallbackName(String typePathString, String method)
         return (typePathString + "$" + method).replaceAll("/", "\\$");
     }
 
-    public CompiledBlockCallback getBlockCallback(String method, String file, int line, Object scriptObject) {
-        Class typeClass = scriptObject.getClass();
-        String typePathString = p(typeClass);
-        String mname = getBlockCallbackName(typePathString, method);
-        try {
-            Class c = tryBlockCallbackClass(mname, COMPILED_BLOCK_SUPER_CLASS);
-            if (c == null) {
-                synchronized (syncObject) {
-                    c = tryBlockCallbackClass(mname, COMPILED_BLOCK_SUPER_CLASS);
-                    if (c == null) {
-                        if (RubyInstanceConfig.JIT_LOADING_DEBUG) {
-                            LOG.debug("no generated handle in classloader for: {}", mname);
-                        }
-                        byte[] bytes = getBlockCallbackOffline(method, file, line, typePathString);
-                        c = endClassWithBytes(bytes, mname);
-                    } else {
-                        if (RubyInstanceConfig.JIT_LOADING_DEBUG) {
-                            LOG.debug("found generated handle in classloader for: {}", mname);
-                        }
-                    }
-                }
-            }
-
-            CompiledBlockCallback ic = (CompiledBlockCallback) c.getConstructor(Object.class).newInstance(scriptObject);
-            return ic;
-        } catch (IllegalArgumentException e) {
-            throw e;
-        } catch (Exception e) {
-            throw new IllegalArgumentException(e.getMessage());
-        }
-    }
-
-    @Override
-    public byte[] getBlockCallbackOffline(String method, String file, int line, String classname) {
-        String mname = getBlockCallbackName(classname, method);
-        ClassWriter cw = createBlockCtor(mname, classname);
-        SkinnyMethodAdapter mv = startBlockCall(cw);
-        mv.aload(0);
-        mv.getfield(mname, "$scriptObject", "L" + classname + ";");
-        mv.aloadMany(1, 2, 3, 4);
-        mv.invokestatic(classname, method, sig(
-                IRubyObject.class, "L" + classname + ";", ThreadContext.class,
-                        IRubyObject.class, IRubyObject.class, Block.class));
-        mv.areturn();
-        mv.end();
-
-        mv = new SkinnyMethodAdapter(cw, ACC_PUBLIC, "getFile", sig(String.class), null, null);
-        mv.start();
-        mv.ldc(file);
-        mv.areturn();
-        mv.end();
-
-        mv = new SkinnyMethodAdapter(cw, ACC_PUBLIC, "getLine", sig(int.class), null, null);
-        mv.start();
-        mv.ldc(line);
-        mv.ireturn();
-        mv.end();
-
-        return endCallOffline(cw);
-    }
-
-    public CompiledBlockCallback19 getBlockCallback19(String method, String file, int line, Object scriptObject) {
-        Class typeClass = scriptObject.getClass();
-        String typePathString = p(typeClass);
-        String mname = getBlockCallbackName(typePathString, method);
-        try {
-            Class c = tryBlockCallback19Class(mname, COMPILED_BLOCK_19_INTERFACE);
-            if (c == null) {
-                synchronized (syncObject) {
-                    c = tryBlockCallback19Class(mname, COMPILED_BLOCK_19_INTERFACE);
-                    if (c == null) {
-                        if (RubyInstanceConfig.JIT_LOADING_DEBUG) {
-                            LOG.debug("no generated handle in classloader for: {}", mname);
-                        }
-                        byte[] bytes = getBlockCallback19Offline(method, file, line, typePathString);
-                        c = endClassWithBytes(bytes, mname);
-                    } else {
-                        if (RubyInstanceConfig.JIT_LOADING_DEBUG) {
-                            LOG.debug("found generated handle in classloader for: {}", mname);
-                        }
-                    }
-                }
-            }
-
-            CompiledBlockCallback19 ic = (CompiledBlockCallback19) c.getConstructor(Object.class).newInstance(scriptObject);
-            return ic;
-        } catch (IllegalArgumentException e) {
-            throw e;
-        } catch (Exception e) {
-            throw new IllegalArgumentException(e.getMessage());
-        }
-    }
-
-    @Override
-    public byte[] getBlockCallback19Offline(String method, String file, int line, String classname) {
-        String mnamePath = getBlockCallbackName(classname, method);
-        ClassWriter cw = createBlockCtor19(mnamePath, classname);
-        SkinnyMethodAdapter mv = startBlockCall19(cw);
-        mv.aload(0);
-        mv.getfield(mnamePath, "$scriptObject", "L" + classname + ";");
-        mv.aloadMany(1, 2, 3, 4);
-        mv.invokestatic(classname, method, sig(
-                IRubyObject.class, "L" + classname + ";", ThreadContext.class,
-                        IRubyObject.class, IRubyObject[].class, Block.class));
-        mv.areturn();
-        mv.end();
-
-        mv = new SkinnyMethodAdapter(cw, ACC_PUBLIC, "getFile", sig(String.class), null, null);
-        mv.start();
-        mv.ldc(file);
-        mv.areturn();
-        mv.end();
-
-        mv = new SkinnyMethodAdapter(cw, ACC_PUBLIC, "getLine", sig(int.class), null, null);
-        mv.start();
-        mv.ldc(line);
-        mv.ireturn();
-        mv.end();
-
-        return endCallOffline(cw);
-    }
-
-    private SkinnyMethodAdapter startBlockCall(ClassWriter cw) {
-        SkinnyMethodAdapter mv = new SkinnyMethodAdapter(cw, ACC_PUBLIC | ACC_SYNTHETIC | ACC_FINAL, "call", BLOCK_CALL_SIG, null, null);
-
-        mv.visitCode();
-        return mv;
-    }
-
-    private SkinnyMethodAdapter startBlockCall19(ClassWriter cw) {
-        SkinnyMethodAdapter mv = new SkinnyMethodAdapter(cw, ACC_PUBLIC | ACC_SYNTHETIC | ACC_FINAL, "call", BLOCK_CALL_SIG19, null, null);
-
-        mv.visitCode();
-        return mv;
-    }
-
-    private ClassWriter createBlockCtor(String namePath, String classname) {
-        String ciClassname = "L" + classname + ";";
-        ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES);
-        cw.visit(RubyInstanceConfig.JAVA_VERSION, ACC_PUBLIC + ACC_SUPER, namePath, null, COMPILED_BLOCK_SUPER_CLASS_NAME, null);
-        cw.visitSource(namePath, null);
-        cw.visitField(ACC_PRIVATE | ACC_FINAL, "$scriptObject", ciClassname, null, null);
-        SkinnyMethodAdapter mv = new SkinnyMethodAdapter(cw, ACC_PUBLIC, "<init>", sig(Void.TYPE, params(Object.class)), null, null);
-        mv.start();
-        mv.aload(0);
-        mv.invokespecial(p(CompiledBlockCallback.class), "<init>", sig(void.class));
-        mv.aloadMany(0, 1);
-        mv.checkcast(classname);
-        mv.putfield(namePath, "$scriptObject", ciClassname);
-        mv.voidreturn();
-        mv.end();
-
-        return cw;
-    }
-
-    private ClassWriter createBlockCtor19(String namePath, String classname) {
-        String ciClassname = "L" + classname + ";";
-        ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS | ClassWriter.COMPUTE_FRAMES);
-        cw.visit(RubyInstanceConfig.JAVA_VERSION, ACC_PUBLIC + ACC_SUPER, namePath, null, p(Object.class), new String[] {COMPILED_BLOCK_19_INTERFACE_NAME});
-        cw.visitSource(namePath, null);
-        cw.visitField(ACC_PRIVATE | ACC_FINAL, "$scriptObject", ciClassname, null, null);
-        SkinnyMethodAdapter mv = new SkinnyMethodAdapter(cw, ACC_PUBLIC, "<init>", sig(Void.TYPE, params(Object.class)), null, null);
-        mv.start();
-        mv.aload(0);
-        mv.invokespecial(p(Object.class), "<init>", sig(void.class));
-        mv.aloadMany(0, 1);
-        mv.checkcast(classname);
-        mv.putfield(namePath, "$scriptObject", ciClassname);
-        mv.voidreturn();
-        mv.end();
-
-        return cw;
-    }
-
     /**
      * Use code generation to provide a method handle based on an annotated Java
      * method.

diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/MethodArgs2.java b/core/src/main/java/org/jruby/internal/runtime/methods/MethodArgs2.java
@@ -1,6 +1,13 @@
 package org.jruby.internal.runtime.methods;
 
 /**
+ * Get a list of argument descriptors in prefixed form.
+ * 
+ * The prefixed form has a single leading character to indicate the type of argument
+ * followed immediately by the name of the argument.
+ * 
+ * @see IRMethodArgs
+ * @see org.jruby.runtime.ArgumentType
  */
 public interface MethodArgs2 {
     public String[] getParameterList();

diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/MixedModeIRMethod.java b/core/src/main/java/org/jruby/internal/runtime/methods/MixedModeIRMethod.java
@@ -8,6 +8,7 @@
 import org.jruby.ir.interpreter.InterpreterContext;
 import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.parser.StaticScope;
+import org.jruby.runtime.ArgumentDescriptor;
 import org.jruby.runtime.Arity;
 import org.jruby.runtime.Block;
 import org.jruby.runtime.DynamicScope;
@@ -64,9 +65,9 @@ public StaticScope getStaticScope() {
         return method.getStaticScope();
     }
 
-    public String[] getParameterList() {
+    public ArgumentDescriptor[] getArgumentDescriptors() {
         ensureInstrsReady(); // Make sure method is minimally built before returning this info
-        return ((IRMethod) method).getArgDesc();
+        return ((IRMethod) method).getArgumentDescriptors();
     }
 
     public Signature getSignature() {

diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/ProcMethod.java b/core/src/main/java/org/jruby/internal/runtime/methods/ProcMethod.java
@@ -32,10 +32,12 @@
 
 import org.jruby.RubyModule;
 import org.jruby.RubyProc;
-import org.jruby.ast.ArgsNode;
+import org.jruby.runtime.ArgumentDescriptor;
 import org.jruby.runtime.Arity;
 import org.jruby.runtime.Block;
+import org.jruby.runtime.Helpers;
 import org.jruby.runtime.PositionAware;
+import org.jruby.runtime.Signature;
 import org.jruby.runtime.ThreadContext;
 import org.jruby.runtime.Visibility;
 import org.jruby.runtime.builtin.IRubyObject;
@@ -44,7 +46,7 @@
  * 
  * @author jpetersen
  */
-public class ProcMethod extends DynamicMethod implements PositionAware, MethodArgs2 {
+public class ProcMethod extends DynamicMethod implements PositionAware, IRMethodArgs {
     private RubyProc proc;
 
     /**
@@ -57,9 +59,6 @@ public ProcMethod(RubyModule implementationClass, RubyProc proc, Visibility visi
         this.proc = proc;
     }
 
-    /**
-     * @see org.jruby.runtime.ICallable#call(Ruby, IRubyObject, String, IRubyObject[], boolean)
-     */
     public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule klazz, String name, IRubyObject[] args, Block block) {
         return proc.call(context, args, self, block);
     }
@@ -88,7 +87,13 @@ public int getLine() {
         return proc.getBlock().getBody().getLine();
     }
 
-    public String[] getParameterList() {
-        return proc.getBlock().getBody().getParameterList();
+    @Override
+    public Signature getSignature() {
+        return proc.getBlock().getBody().getSignature();
+    }
+
+    @Override
+    public ArgumentDescriptor[] getArgumentDescriptors() {
+        return proc.getBlock().getBody().getArgumentDescriptors();
     }
 }
diff --git a/core/src/main/java/org/jruby/internal/runtime/methods/ReflectionMethodFactory.java b/core/src/main/java/org/jruby/internal/runtime/methods/ReflectionMethodFactory.java
@@ -29,29 +29,25 @@
  ***** END LICENSE BLOCK *****/
 package org.jruby.internal.runtime.methods;
 
-import java.lang.reflect.InvocationTargetException;
-import java.lang.reflect.Method;
-import java.lang.reflect.Modifier;
-
-import java.util.ArrayList;
-import java.util.List;
 import org.jruby.RubyModule;
 import org.jruby.anno.JRubyMethod;
 import org.jruby.anno.JavaMethodDescriptor;
 import org.jruby.anno.TypePopulator;
 import org.jruby.lexer.yacc.ISourcePosition;
 import org.jruby.parser.StaticScope;
-import org.jruby.runtime.Arity;
 import org.jruby.runtime.Block;
-import org.jruby.runtime.CompiledBlockCallback;
-import org.jruby.runtime.CompiledBlockCallback19;
 import org.jruby.runtime.MethodFactory;
 import org.jruby.runtime.ThreadContext;
 import org.jruby.runtime.Visibility;
 import org.jruby.runtime.builtin.IRubyObject;
 import org.jruby.util.log.Logger;
 import org.jruby.util.log.LoggerFactory;
 
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+import java.util.ArrayList;
+import java.util.List;
+
 /**
  * This MethodFactory uses reflection to provide method handles. Reflection is
  * typically slower than code-generated handles, but it does provide a simple
@@ -178,78 +174,4 @@ public DynamicMethod getAnnotatedMethod(RubyModule implementationClass, List<Jav
             throw new RuntimeException(e);
         }
     }
-
-    public CompiledBlockCallback getBlockCallback(String method, final String file, final int line, final Object scriptObject) {
-        try {
-            Class scriptClass = scriptObject.getClass();
-            final Method blockMethod = scriptClass.getMethod(method, scriptClass, ThreadContext.class, IRubyObject.class, IRubyObject.class, Block.class);
-            return new CompiledBlockCallback() {
-                public IRubyObject call(ThreadContext context, IRubyObject self, IRubyObject args, Block block) {
-                    try {
-                        return (IRubyObject)blockMethod.invoke(null, scriptObject, context, self, args, block);
-                    } catch (IllegalAccessException ex) {
-                        throw new RuntimeException(ex);
-                    } catch (IllegalArgumentException ex) {
-                        throw new RuntimeException(ex);
-                    } catch (InvocationTargetException ex) {
-                        Throwable cause = ex.getCause();
-                        if (cause instanceof RuntimeException) {
-                            throw (RuntimeException) cause;
-                        } else if (cause instanceof Error) {
-                            throw (Error) cause;
-                        } else {
-                            throw new RuntimeException(ex);
-                        }
-                    }
-                }
-
-                public String getFile() {
-                    return file;
-                }
-
-                public int getLine() {
-                    return line;
-                }
-            };
-        } catch (NoSuchMethodException nsme) {
-            throw new RuntimeException(nsme);
-        }
-    }
-
-    public CompiledBlockCallback19 getBlockCallback19(String method, final String file, final int line, final Object scriptObject) {
-        try {
-            Class scriptClass = scriptObject.getClass();
-            final Method blockMethod = scriptClass.getMethod(method, scriptClass, ThreadContext.class, IRubyObject.class, IRubyObject[].class, Block.class);
-            return new CompiledBlockCallback19() {
-                public IRubyObject call(ThreadContext context, IRubyObject self, IRubyObject[] args, Block block) {
-                    try {
-                        return (IRubyObject)blockMethod.invoke(null, scriptObject, context, self, args, block);
-                    } catch (IllegalAccessException ex) {
-                        throw new RuntimeException(ex);
-                    } catch (IllegalArgumentException ex) {
-                        throw new RuntimeException(ex);
-                    } catch (InvocationTargetException ex) {
-                        Throwable cause = ex.getCause();
-                        if (cause instanceof RuntimeException) {
-                            throw (RuntimeException) cause;
-                        } else if (cause instanceof Error) {
-                            throw (Error) cause;
-                        } else {
-                            throw new RuntimeException(ex);
-                        }
-                    }
-                }
-
-                public String getFile() {
-                    return file;
-                }
-
-                public int getLine() {
-                    return line;
-                }
-            };
-        } catch (NoSuchMethodException nsme) {
-            throw new RuntimeException(nsme);
-        }
-    }
 }
diff --git a/core/src/main/java/org/jruby/ir/IRBuilder.java b/core/src/main/java/org/jruby/ir/IRBuilder.java
diff --git a/core/src/main/java/org/jruby/ir/IRClosure.java b/core/src/main/java/org/jruby/ir/IRClosure.java
@@ -6,11 +6,9 @@
 import org.jruby.ir.interpreter.ClosureInterpreterContext;
 import org.jruby.ir.interpreter.InterpreterContext;
 import org.jruby.ir.operands.*;
-import org.jruby.ir.representations.CFG;
 import org.jruby.ir.transformations.inlining.CloneInfo;
 import org.jruby.ir.transformations.inlining.SimpleCloneInfo;
 import org.jruby.parser.StaticScope;
-import org.jruby.runtime.Arity;
 import org.jruby.runtime.BlockBody;
 import org.jruby.runtime.IRBlockBody;
 import org.jruby.runtime.InterpretedIRBlockBody;
@@ -28,9 +26,6 @@ public class IRClosure extends IRScope {
 
     private boolean isBeginEndBlock;
 
-    /** The parameter names, for Proc#parameters */
-    private String[] parameterList;
-
     private Signature signature;
 
     /** Added for interp/JIT purposes */
@@ -48,7 +43,6 @@ protected IRClosure(IRManager manager, IRScope lexicalParent, String fileName, i
         this.closureId = lexicalParent.getNextClosureId();
         setName(prefix + closureId);
         this.body = null;
-        this.parameterList = new String[] {};
     }
 
     /** Used by cloning code */
@@ -107,16 +101,6 @@ public boolean isBeginEndBlock() {
         return isBeginEndBlock;
     }
 
-    public void setParameterList(String[] parameterList) {
-        this.parameterList = parameterList;
-
-        if (!getManager().isDryRun()) this.body.setParameterList(parameterList);
-    }
-
-    public String[] getParameterList() {
-        return this.parameterList;
-    }
-
     @Override
     public int getNextClosureId() {
         return getLexicalParent().getNextClosureId();
@@ -250,7 +234,6 @@ public LocalVariable getLocalVariable(String name, int depth) {
     protected IRClosure cloneForInlining(CloneInfo ii, IRClosure clone) {
         // SSS FIXME: This is fragile. Untangle this state.
         // Why is this being copied over to InterpretedIRBlockBody?
-        clone.setParameterList(this.parameterList);
         clone.isBeginEndBlock = this.isBeginEndBlock;
 
         SimpleCloneInfo clonedII = ii.cloneForCloningClosure(clone);
@@ -296,10 +279,6 @@ public void setName(String name) {
         super.setName(getLexicalParent().getName() + name);
     }
 
-    public Arity getArity() {
-        return signature.arity();
-    }
-
     public Signature getSignature() {
         return signature;
     }

diff --git a/core/src/main/java/org/jruby/ir/IRMethod.java b/core/src/main/java/org/jruby/ir/IRMethod.java
@@ -5,6 +5,7 @@
 import java.util.HashMap;
 import java.util.Map;
 import org.jruby.ast.MethodDefNode;
+import org.jruby.runtime.ArgumentDescriptor;
 import org.jruby.ir.interpreter.InterpreterContext;
 import org.jruby.ir.operands.LocalVariable;
 import org.jruby.ir.representations.BasicBlock;
@@ -13,9 +14,6 @@
 public class IRMethod extends IRScope {
     public final boolean isInstanceMethod;
 
-    // Argument description of the form [:req, "a"], [:opt, "b"] ..
-    private String[] argDesc;
-
     // Signatures to the jitted versions of this method
     private Map<Integer, MethodType> signatures;
 
@@ -30,7 +28,6 @@ public IRMethod(IRManager manager, IRScope lexicalParent, MethodDefNode defn, St
 
         this.defn = defn;
         this.isInstanceMethod = isInstanceMethod;
-        this.argDesc = null;
         this.signatures = null;
 
         if (!getManager().isDryRun() && staticScope != null) {
@@ -64,17 +61,6 @@ public IRScopeType getScopeType() {
         return isInstanceMethod ? IRScopeType.INSTANCE_METHOD : IRScopeType.CLASS_METHOD;
     }
 
-    public String[] getArgDesc() {
-        return argDesc;
-    }
-
-    /**
-     * Set upon completion of IRBuild of this IRMethod.
-     */
-    public void setArgDesc(String[] argDesc) {
-        this.argDesc = argDesc;
-    }
-
     @Override
     protected LocalVariable findExistingLocalVariable(String name, int scopeDepth) {
         assert scopeDepth == 0: "Local variable depth in IRMethod should always be zero (" + name + " had depth of " + scopeDepth + ")";

diff --git a/core/src/main/java/org/jruby/ir/IRScope.java b/core/src/main/java/org/jruby/ir/IRScope.java
@@ -21,6 +21,8 @@
 
 import java.util.*;
 import java.util.concurrent.atomic.AtomicInteger;
+
+import org.jruby.runtime.ArgumentDescriptor;
 import org.jruby.util.log.Logger;
 import org.jruby.util.log.LoggerFactory;
 
@@ -61,6 +63,8 @@ public abstract class IRScope implements ParseResult {
     private static final Collection<IRClosure> NO_CLOSURES = Collections.unmodifiableCollection(new ArrayList<IRClosure>(0));
 
     private static AtomicInteger globalScopeCount = new AtomicInteger();
+    // Argument description
+    protected ArgumentDescriptor[] argDesc = ArgumentDescriptor.EMPTY_ARRAY;
 
     /** Unique global scope id */
     private int scopeId;
@@ -191,6 +195,7 @@ public IRScope(IRManager manager, IRScope lexicalParent, String name,
         this.scopeId = globalScopeCount.getAndIncrement();
 
         setupLexicalContainment();
+        this.argDesc = null;
     }
 
     private void setupLexicalContainment() {
@@ -777,6 +782,17 @@ public LocalVariable lookupExistingLVar(String name) {
         return localVars.get(name);
     }
 
+    public ArgumentDescriptor[] getArgumentDescriptors() {
+        return argDesc;
+    }
+
+    /**
+     * Set upon completion of IRBuild of this IRMethod.
+     */
+    public void setArgumentDescriptors(ArgumentDescriptor[] argDesc) {
+        this.argDesc = argDesc;
+    }
+
     protected LocalVariable findExistingLocalVariable(String name, int depth) {
         return localVars.get(name);
     }

diff --git a/core/src/main/java/org/jruby/ir/interpreter/BodyInterpreterEngine.java b/core/src/main/java/org/jruby/ir/interpreter/BodyInterpreterEngine.java
@@ -56,14 +56,14 @@ public IRubyObject interpret(ThreadContext context, IRubyObject self, Interprete
         while (ipc < n) {
             Instr instr = instrs[ipc];
 
-            ipc++;
-
             Operation operation = instr.getOperation();
             if (debug) {
-                Interpreter.LOG.info("I: {}", instr);
+                Interpreter.LOG.info("I: {" + ipc + "} ", instr);
                 Interpreter.interpInstrsCount++;
             }
 
+            ipc++;
+
             try {
                 switch (operation) {
                     case RETURN:

diff --git a/core/src/main/java/org/jruby/ir/interpreter/InterpreterEngine.java b/core/src/main/java/org/jruby/ir/interpreter/InterpreterEngine.java
@@ -129,16 +129,18 @@ public IRubyObject interpret(ThreadContext context, IRubyObject self,
         // Enter the looooop!
         while (ipc < n) {
             Instr instr = instrs[ipc];
-            ipc++;
+
             Operation operation = instr.getOperation();
             if (debug) {
-                Interpreter.LOG.info("I: {}", instr);
+                Interpreter.LOG.info("I: {" + ipc + "} ", instr);
                 Interpreter.interpInstrsCount++;
             } else if (profile) {
                 Profiler.instrTick(operation);
                 Interpreter.interpInstrsCount++;
             }
 
+            ipc++;
+
             try {
                 switch (operation.opClass) {
                     case INT_OP:

diff --git a/core/src/main/java/org/jruby/ir/interpreter/StartupInterpreterEngine.java b/core/src/main/java/org/jruby/ir/interpreter/StartupInterpreterEngine.java
@@ -56,16 +56,18 @@ public IRubyObject interpret(ThreadContext context, IRubyObject self,
         // Enter the looooop!
         while (ipc < n) {
             Instr instr = instrs[ipc];
-            ipc++;
+
             Operation operation = instr.getOperation();
             if (debug) {
-                Interpreter.LOG.info("I: {}", instr);
+                Interpreter.LOG.info("I: {" + ipc + "} ", instr);
                 Interpreter.interpInstrsCount++;
             } else if (profile) {
                 Profiler.instrTick(operation);
                 Interpreter.interpInstrsCount++;
             }
 
+            ipc++;
+
             try {
                 switch (operation.opClass) {
                     case ARG_OP:

diff --git a/core/src/main/java/org/jruby/ir/runtime/IRRuntimeHelpers.java b/core/src/main/java/org/jruby/ir/runtime/IRRuntimeHelpers.java
@@ -456,11 +456,10 @@ public static IRubyObject yieldSpecific(ThreadContext context, Object blk) {
         return b.yieldSpecific(context);
     }
 
-    public static IRubyObject[] convertValueIntoArgArray(ThreadContext context, IRubyObject value, Arity arity, boolean argIsArray) {
+    public static IRubyObject[] convertValueIntoArgArray(ThreadContext context, IRubyObject value, int blockArity, boolean argIsArray) {
         // SSS FIXME: This should not really happen -- so, some places in the runtime library are breaking this contract.
         if (argIsArray && !(value instanceof RubyArray)) argIsArray = false;
 
-        int blockArity = arity.getValue();
         switch (blockArity) {
             case -1 : return argIsArray ? ((RubyArray)value).toJavaArray() : new IRubyObject[] { value };
             case  0 : return new IRubyObject[] { value };
@@ -497,7 +496,7 @@ public static Block getBlockFromObject(ThreadContext context, Object value) {
         } else if (value instanceof RubyProc) {
             block = ((RubyProc) value).getBlock();
         } else if (value instanceof RubyMethod) {
-            block = ((RubyProc)((RubyMethod)value).to_proc(context, null)).getBlock();
+            block = ((RubyProc)((RubyMethod)value).to_proc(context)).getBlock();
         } else if ((value instanceof IRubyObject) && ((IRubyObject)value).isNil()) {
             block = Block.NULL_BLOCK;
         } else if (value instanceof IRubyObject) {

diff --git a/core/src/main/java/org/jruby/ir/targets/JVMVisitor.java b/core/src/main/java/org/jruby/ir/targets/JVMVisitor.java
@@ -174,7 +174,12 @@ public void emitScope(IRScope scope, String name, Signature signature, boolean s
             }
 
             // ensure there's at least one instr per block
-            if (bb.getInstrs().size() == 0) m.adapter.nop();
+            /* FIXME: (CON 20150507) This used to filter blocks that had no instructions and only emit nop for them,
+                      but this led to BBs with no *bytecode-emitting* instructions failing to have a nop and triggering
+                      verification errors when we attached an exception-handling range to them (because the leading
+                      label failed to anchor anywhere, or anchored the same place as the trailing label). Until we can
+                      detect that a BB will not emit any code, we return to always emitting the nop. */
+            m.adapter.nop();
 
             // visit remaining instrs
             for (Instr instr : bb.getInstrs()) {

diff --git a/core/src/main/java/org/jruby/runtime/ArgumentDescriptor.java b/core/src/main/java/org/jruby/runtime/ArgumentDescriptor.java
@@ -0,0 +1,43 @@
+package org.jruby.runtime;
+
+import org.jruby.Ruby;
+import org.jruby.RubyArray;
+
+/**
+ * A description of a single argument in a Ruby argument list.
+ */
+public class ArgumentDescriptor {
+    /** The type of the argument */
+    public final ArgumentType type;
+
+    /** The name of the argument */
+    public final String name;
+
+    public static final ArgumentDescriptor[] EMPTY_ARRAY = new ArgumentDescriptor[0];
+
+    public ArgumentDescriptor(ArgumentType type, String name) {
+        this.type = type;
+        this.name = name;
+    }
+
+    public ArgumentDescriptor(ArgumentType type) {
+        this(type, null);
+    }
+
+    /**
+     * Generate the prefixed version of this descriptor.
+     *
+     * @see org.jruby.internal.runtime.methods.MethodArgs2
+     */
+    public String toPrefixForm() {
+        return type.renderPrefixForm(name);
+    }
+
+    public RubyArray toArrayForm(Ruby runtime, boolean isLambda) {
+        if (type == ArgumentType.req && !isLambda) {
+            return ArgumentType.opt.toArrayForm(runtime, name);
+        } else {
+            return type.toArrayForm(runtime, name);
+        }
+    }
+}
diff --git a/core/src/main/java/org/jruby/runtime/ArgumentType.java b/core/src/main/java/org/jruby/runtime/ArgumentType.java
@@ -0,0 +1,55 @@
+package org.jruby.runtime;
+
+import org.jruby.Ruby;
+import org.jruby.RubyArray;
+
+/**
+ * Created by headius on 5/8/15.
+ */
+public enum ArgumentType {
+    key("key", "k", false),
+    keyreq("keyreq", "K", false),
+    keyrest("keyrest", "e", false),
+    block("block", "b", false),
+    opt("opt", "o", false),
+    rest("rest", "r", false),
+    req("req", "q", false),
+    anonreq("req", "n", true),
+    anonopt("opt", "O", true),
+    anonrest("rest", "R", true),
+    anonkeyrest("keyrest", "N", true);
+
+    ArgumentType(String symbolicName, String prefix, boolean anonymous) {
+        this.symbolicName = symbolicName;
+        this.prefix = prefix;
+        this.anonymous = anonymous;
+    }
+
+    public static ArgumentType valueOf(char prefix) {
+        switch (prefix) {
+            case 'k': return key;
+            case 'K': return keyreq;
+            case 'e': return keyrest;
+            case 'b': return block;
+            case 'o': return opt;
+            case 'r': return rest;
+            case 'q': return req;
+            case 'R': return anonrest;
+            case 'n': return anonreq;
+            case 'O': return anonopt;
+            default: return null;
+        }
+    }
+
+    public String renderPrefixForm(String name) {
+        return anonymous ? String.valueOf(prefix) : prefix + name;
+    }
+
+    public RubyArray toArrayForm(Ruby runtime, String name) {
+        return anonymous ? runtime.newArray(runtime.newSymbol(symbolicName)) : runtime.newArray(runtime.newSymbol(symbolicName), runtime.newSymbol(name));
+    }
+
+    public final String symbolicName;
+    public final String prefix;
+    public final boolean anonymous;
+}
diff --git a/core/src/main/java/org/jruby/runtime/BlockBody.java b/core/src/main/java/org/jruby/runtime/BlockBody.java
@@ -36,27 +36,19 @@
 import org.jruby.EvalType;
 import org.jruby.RubyArray;
 import org.jruby.RubyProc;
-import org.jruby.common.IRubyWarnings.ID;
+import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.parser.StaticScope;
 import org.jruby.runtime.builtin.IRubyObject;
 
 /**
  * The executable body portion of a closure.
  */
 public abstract class BlockBody {
-    // FIXME: Maybe not best place, but move it to a good home
-    public static final int ZERO_ARGS = 0;
-    public static final int MULTIPLE_ASSIGNMENT = 1;
-    public static final int ARRAY = 2;
-    public static final int SINGLE_RESTARG = 3;
-
     public static final String[] EMPTY_PARAMETER_LIST = new String[0];
 
-    protected final int argumentType;
     protected final Signature signature;
 
-    public BlockBody(int argumentType, Signature signature) {
-        this.argumentType = argumentType;
+    public BlockBody(Signature signature) {
         this.signature = signature;
     }
 
@@ -122,10 +114,6 @@ public IRubyObject yield(ThreadContext context, IRubyObject value,
         return yield(context, value, binding, type);
     }
 
-    public int getArgumentType() {
-        return argumentType;
-    }
-
     public IRubyObject call(ThreadContext context, Binding binding, Block.Type type) {
         IRubyObject[] args = IRubyObject.NULL_ARRAY;
         args = prepareArgumentsForCall(context, args, type);
@@ -217,43 +205,25 @@ public boolean isGiven() {
     public abstract int getLine();
 
     public IRubyObject[] prepareArgumentsForCall(ThreadContext context, IRubyObject[] args, Block.Type type) {
-        switch (type) {
-        case NORMAL: {
-//            assert false : "can this happen?";
-            if (args.length == 1 && args[0] instanceof RubyArray) {
-                if (argumentType == MULTIPLE_ASSIGNMENT || argumentType == SINGLE_RESTARG) {
-                    args = ((RubyArray) args[0]).toJavaArray();
-                }
-                break;
-            }
-        }
-        case PROC: {
-            if (args.length == 1 && args[0] instanceof RubyArray) {
-                if (argumentType == MULTIPLE_ASSIGNMENT && argumentType != SINGLE_RESTARG) {
-                    args = ((RubyArray) args[0]).toJavaArray();
-                }
-            }
-            break;
-        }
-        case LAMBDA:
-            if (argumentType == ARRAY && args.length != 1) {
-                context.runtime.getWarnings().warn(ID.MULTIPLE_VALUES_FOR_BLOCK, "multiple values for a block parameter (" + args.length + " for " + getSignature().arityValue() + ")");
-                if (args.length == 0) {
-                    args = context.runtime.getSingleNilArray();
-                } else {
-                    args = new IRubyObject[] {context.runtime.newArrayNoCopy(args)};
-                }
-            } else {
-                getSignature().checkArity(context.runtime, args);
+        if (type == Block.Type.LAMBDA) {
+            signature.checkArity(context.runtime, args);
+        } else {
+            // SSS FIXME: How is it even possible to "call" a NORMAL block?
+            // I thought only procs & lambdas can be called, and blocks are yielded to.
+            if (args.length == 1) {
+                // Convert value to arg-array, unwrapping where necessary
+                args = IRRuntimeHelpers.convertValueIntoArgArray(context, args[0], signature.arityValue(), type == Block.Type.NORMAL && args[0] instanceof RubyArray);
+            } else if (getSignature().arityValue() == 1 && !getSignature().restKwargs()) {
+                // discard excess arguments
+                args = args.length == 0 ? context.runtime.getSingleNilArray() : new IRubyObject[] { args[0] };
             }
-            break;
         }
 
         return args;
     }
 
-    public String[] getParameterList() {
-        return EMPTY_PARAMETER_LIST;
+    public ArgumentDescriptor[] getArgumentDescriptors() {
+        return ArgumentDescriptor.EMPTY_ARRAY;
     }
 
     public static final BlockBody NULL_BODY = new NullBlockBody();

diff --git a/core/src/main/java/org/jruby/runtime/CallBlock.java b/core/src/main/java/org/jruby/runtime/CallBlock.java
@@ -55,7 +55,7 @@ public static Block newCallClosure(IRubyObject self, RubyModule imClass, Arity a
     }
 
     private CallBlock(Signature signature, BlockCallback callback, ThreadContext context) {
-        super(BlockBody.SINGLE_RESTARG, signature);
+        super(signature);
         this.callback = callback;
         this.dummyScope = context.runtime.getStaticScopeFactory().getDummyScope();
     }

diff --git a/core/src/main/java/org/jruby/runtime/CallBlock19.java b/core/src/main/java/org/jruby/runtime/CallBlock19.java
@@ -57,7 +57,7 @@ public static Block newCallClosure(IRubyObject self, RubyModule imClass, Arity a
     }
 
     public CallBlock19(Signature signature, BlockCallback callback, ThreadContext context) {
-        super(BlockBody.SINGLE_RESTARG, signature);
+        super(signature);
         this.callback = callback;
         this.dummy = context.runtime.getStaticScopeFactory().getDummyScope();
     }

diff --git a/core/src/main/java/org/jruby/runtime/CallbackFactory.java b/core/src/main/java/org/jruby/runtime/CallbackFactory.java
diff --git a/core/src/main/java/org/jruby/runtime/CompiledBlock.java b/core/src/main/java/org/jruby/runtime/CompiledBlock.java
diff --git a/core/src/main/java/org/jruby/runtime/CompiledBlock19.java b/core/src/main/java/org/jruby/runtime/CompiledBlock19.java
diff --git a/core/src/main/java/org/jruby/runtime/CompiledBlockCallback.java b/core/src/main/java/org/jruby/runtime/CompiledBlockCallback.java
diff --git a/core/src/main/java/org/jruby/runtime/CompiledBlockCallback19.java b/core/src/main/java/org/jruby/runtime/CompiledBlockCallback19.java
diff --git a/core/src/main/java/org/jruby/runtime/CompiledBlockLight.java b/core/src/main/java/org/jruby/runtime/CompiledBlockLight.java
diff --git a/core/src/main/java/org/jruby/runtime/CompiledBlockLight19.java b/core/src/main/java/org/jruby/runtime/CompiledBlockLight19.java
diff --git a/core/src/main/java/org/jruby/runtime/CompiledIRBlockBody.java b/core/src/main/java/org/jruby/runtime/CompiledIRBlockBody.java
@@ -3,6 +3,7 @@
 import org.jruby.EvalType;
 import org.jruby.ir.IRClosure;
 import org.jruby.ir.IRFlags;
+import org.jruby.ir.IRMethod;
 import org.jruby.ir.IRScope;
 import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.runtime.Block.Type;
@@ -18,7 +19,7 @@ public class CompiledIRBlockBody extends IRBlockBody {
     protected boolean usesKwargs;
 
     public CompiledIRBlockBody(MethodHandle handle, IRScope closure, long encodedSignature) {
-        super(closure.getStaticScope(), ((IRClosure)closure).getParameterList(), closure.getFileName(), closure.getLineNumber(), Signature.decode(encodedSignature));
+        super(closure.getStaticScope(), closure.getFileName(), closure.getLineNumber(), Signature.decode(encodedSignature));
         this.handle = handle;
         this.closure = (IRClosure)closure;
         // FIXME: duplicated from InterpreterContext
@@ -30,6 +31,11 @@ public CompiledIRBlockBody(MethodHandle handle, IRScope closure, long encodedSig
         closure.getStaticScope().determineModule();
     }
 
+    @Override
+    public ArgumentDescriptor[] getArgumentDescriptors() {
+        return closure.getArgumentDescriptors();
+    }
+
     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.

diff --git a/core/src/main/java/org/jruby/runtime/CompiledSharedScopeBlock.java b/core/src/main/java/org/jruby/runtime/CompiledSharedScopeBlock.java
diff --git a/core/src/main/java/org/jruby/runtime/ContextAwareBlockBody.java b/core/src/main/java/org/jruby/runtime/ContextAwareBlockBody.java
@@ -9,14 +9,15 @@ public abstract class ContextAwareBlockBody extends BlockBody {
     /** The static scope for the block body */
     protected StaticScope scope;
 
-    public ContextAwareBlockBody(StaticScope scope, Signature signature, int argumentType) {
-        super(argumentType, signature);
+    public ContextAwareBlockBody(StaticScope scope, Signature signature) {
+        super(signature);
 
         this.scope = scope;
     }
 
+    @Deprecated
     public ContextAwareBlockBody(StaticScope scope, Arity arity, int argumentType) {
-        this(scope, Signature.from(arity), argumentType);
+        this(scope, Signature.from(arity));
     }
 
     protected Frame pre(ThreadContext context, Binding binding) {