First pass attempting to optimize startup time

This patch is a bunch of hacky fixes as a proof of concept attempt to improve startup time. * This fixes the interpreter to interpret IR instructions that the IR builder generates without having to build a CFG or run any passes on them. There is no cloning of in instructions either. * If the scope runs at least N times (N = 20 right now), the CFG is then built, some basic passes are run and future runs will use the new optimized scope. In interpret mode (-X-C), this patch: * reduces startup time for gem list by 20+%. * reduces total user time by ~13% across a bunch of benchmarks. * reduces wall clock time by ~5% across the same benchmarks. * improves peak perf on some of those benchmarks and degrades peak perf on some. In default mode (-X-C), this patch: * reduces total user time by ~20% across a bunch of benchmarks. * reduces wall clock time by ~11% across the same benchmarks. This was passing all tests in an earlier version of this patch before I broke something messing and tweaking something. It is late at night, so pushing this as is. This branch is not ready for merge. It requires: * code cleanup * get rid of hacks * more testing * fixing broken tests
jruby · Feb 18, 2015 · df56604 · df56604
1 parent f3c4b71
commit df56604
Showing 12 changed files with 244 additions and 41 deletions.
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
@@ -36,7 +36,16 @@ public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule claz
         if (IRRuntimeHelpers.isDebug()) doDebug();
 
         InterpreterContext ic = ensureInstrsReady();
-        return ic.engine.interpret(context, self, ic, getImplementationClass().getMethodLocation(), name, block, null);
+        if (ic.hasExplicitCallProtocol()) {
+            return ic.engine.interpret(context, self, ic, getImplementationClass().getMethodLocation(), name, block, null);
+        } else {
+            try {
+                this.pre(ic, context, self, name, block, getImplementationClass());
+                return ic.engine.interpret(context, self, ic, getImplementationClass().getMethodLocation(), name, block, null);
+            } finally {
+                this.post(ic, context);
+            }
+        }
     }
 
     @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
@@ -14,6 +14,7 @@
 import org.jruby.parser.StaticScope;
 import org.jruby.runtime.Arity;
 import org.jruby.runtime.Block;
+import org.jruby.runtime.DynamicScope;
 import org.jruby.runtime.PositionAware;
 import org.jruby.runtime.ThreadContext;
 import org.jruby.runtime.Visibility;
@@ -83,11 +84,35 @@ public Arity getArity() {
         return this.arity;
     }
 
+    protected void post(InterpreterContext ic, ThreadContext context) {
+        // update call stacks (pop: ..)
+        context.popFrame();
+        if (ic.popDynScope()) {
+            context.popScope();
+        }
+    }
+
+    protected void pre(InterpreterContext ic, ThreadContext context, IRubyObject self, String name, Block block, RubyModule implClass) {
+        // update call stacks (push: frame, class, scope, etc.)
+        context.preMethodFrameOnly(implClass, name, self, block);
+        if (ic.pushNewDynScope()) {
+            context.pushScope(DynamicScope.newDynamicScope(ic.getStaticScope()));
+        }
+        context.setCurrentVisibility(getVisibility());
+    }
+
     public InterpreterContext ensureInstrsReady() {
         // Try unsync access first before calling more expensive method for getting IC
         InterpreterContext ic = method.getInterpreterContext();
 
-        return ic == null ? method.prepareForInterpretation() : ic;
+        // Build/rebuild if necessary
+        if (ic == null) {
+            ic = method.prepareForInterpretation();
+        } else if (ic.needsRebuilding()) {
+            ic = method.prepareForInterpretation(true);
+        }
+
+        return ic;
     }
 
     @Override
@@ -105,12 +130,21 @@ public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule claz
         }
     }
 
-    private static IRubyObject INTERPRET_METHOD(ThreadContext context, InterpreterContext ic, RubyModule implClass,
+    private IRubyObject INTERPRET_METHOD(ThreadContext context, InterpreterContext ic, RubyModule implClass,
                                                IRubyObject self, String name, IRubyObject[] args, Block block) {
         try {
             ThreadContext.pushBacktrace(context, name, ic.getFileName(), context.getLine());
 
-            return ic.engine.interpret(context, self, ic, implClass, name, args, block, null);
+            if (ic.hasExplicitCallProtocol()) {
+                return ic.engine.interpret(context, self, ic, implClass, name, args, block, null);
+            } else {
+                try {
+                    this.pre(ic, context, self, name, block, implClass);
+                    return ic.engine.interpret(context, self, ic, implClass, name, args, block, null);
+                } finally {
+                    this.post(ic, context);
+                }
+            }
         } finally {
             ThreadContext.popBacktrace(context);
         }
@@ -131,12 +165,21 @@ public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule claz
         }
     }
 
-    private static IRubyObject INTERPRET_METHOD(ThreadContext context, InterpreterContext ic, RubyModule implClass,
+    private IRubyObject INTERPRET_METHOD(ThreadContext context, InterpreterContext ic, RubyModule implClass,
                                                IRubyObject self, String name, Block block) {
         try {
             ThreadContext.pushBacktrace(context, name, ic.getFileName(), context.getLine());
 
-            return ic.engine.interpret(context, self, ic, implClass, name, block, null);
+            if (ic.hasExplicitCallProtocol()) {
+                return ic.engine.interpret(context, self, ic, implClass, name, block, null);
+            } else {
+                try {
+                    this.pre(ic, context, self, name, block, implClass);
+                    return ic.engine.interpret(context, self, ic, implClass, name, block, null);
+                } finally {
+                    this.post(ic, context);
+                }
+            }
         } finally {
             ThreadContext.popBacktrace(context);
         }
@@ -157,12 +200,21 @@ public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule claz
         }
     }
 
-    private static IRubyObject INTERPRET_METHOD(ThreadContext context, InterpreterContext ic, RubyModule implClass,
+    private IRubyObject INTERPRET_METHOD(ThreadContext context, InterpreterContext ic, RubyModule implClass,
                                                IRubyObject self, String name, IRubyObject arg1, Block block) {
         try {
             ThreadContext.pushBacktrace(context, name, ic.getFileName(), context.getLine());
 
-            return ic.engine.interpret(context, self, ic, implClass, name, arg1, block, null);
+            if (ic.hasExplicitCallProtocol()) {
+                return ic.engine.interpret(context, self, ic, implClass, name, arg1, block, null);
+            } else {
+                try {
+                    this.pre(ic, context, self, name, block, implClass);
+                    return ic.engine.interpret(context, self, ic, implClass, name, arg1, block, null);
+                } finally {
+                    this.post(ic, context);
+                }
+            }
         } finally {
             ThreadContext.popBacktrace(context);
         }
@@ -183,12 +235,21 @@ public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule claz
         }
     }
 
-    private static IRubyObject INTERPRET_METHOD(ThreadContext context, InterpreterContext ic, RubyModule implClass,
+    private IRubyObject INTERPRET_METHOD(ThreadContext context, InterpreterContext ic, RubyModule implClass,
                                                IRubyObject self, String name, IRubyObject arg1, IRubyObject arg2,  Block block) {
         try {
             ThreadContext.pushBacktrace(context, name, ic.getFileName(), context.getLine());
 
-            return ic.engine.interpret(context, self, ic, implClass, name, arg1, arg2, block, null);
+            if (ic.hasExplicitCallProtocol()) {
+                return ic.engine.interpret(context, self, ic, implClass, name, arg1, arg2, block, null);
+            } else {
+                try {
+                    this.pre(ic, context, self, name, block, implClass);
+                    return ic.engine.interpret(context, self, ic, implClass, name, arg1, arg2, block, null);
+                } finally {
+                    this.post(ic, context);
+                }
+            }
         } finally {
             ThreadContext.popBacktrace(context);
         }
@@ -209,12 +270,21 @@ public IRubyObject call(ThreadContext context, IRubyObject self, RubyModule claz
         }
     }
 
-    private static IRubyObject INTERPRET_METHOD(ThreadContext context, InterpreterContext ic, RubyModule implClass,
+    private IRubyObject INTERPRET_METHOD(ThreadContext context, InterpreterContext ic, RubyModule implClass,
                                                IRubyObject self, String name, IRubyObject arg1, IRubyObject arg2, IRubyObject arg3, Block block) {
         try {
             ThreadContext.pushBacktrace(context, name, ic.getFileName(), context.getLine());
 
-            return ic.engine.interpret(context, self, ic, implClass, name, arg1, arg2, arg3, block, null);
+            if (ic.hasExplicitCallProtocol()) {
+                return ic.engine.interpret(context, self, ic, implClass, name, arg1, arg2, arg3, block, null);
+            } else {
+                try {
+                    this.pre(ic, context, self, name, block, implClass);
+                    return ic.engine.interpret(context, self, ic, implClass, name, arg1, arg2, arg3, block, null);
+                } finally {
+                    this.post(ic, context);
+                }
+            }
         } finally {
             ThreadContext.popBacktrace(context);
         }

diff --git a/core/src/main/java/org/jruby/ir/IRClosure.java b/core/src/main/java/org/jruby/ir/IRClosure.java
@@ -106,8 +106,8 @@ public IRClosure(IRManager manager, IRScope lexicalParent, int lineNumber, Stati
     }
 
     @Override
-    public InterpreterContext allocateInterpreterContext(Instr[] instructionList) {
-        return new ClosureInterpreterContext(this, instructionList);
+    public InterpreterContext allocateInterpreterContext(Instr[] instructionList, boolean rebuild) {
+        return new ClosureInterpreterContext(this, instructionList, rebuild);
     }
 
     public void setBeginEndBlock() {

diff --git a/core/src/main/java/org/jruby/ir/IREvalScript.java b/core/src/main/java/org/jruby/ir/IREvalScript.java
@@ -35,8 +35,8 @@ public IREvalScript(IRManager manager, IRScope lexicalParent, String fileName,
     }
 
     @Override
-    public InterpreterContext allocateInterpreterContext(Instr[] instructionList) {
-        return new BeginEndInterpreterContext(this, instructionList);
+    public InterpreterContext allocateInterpreterContext(Instr[] instructionList, boolean rebuild) {
+        return new BeginEndInterpreterContext(this, instructionList, rebuild);
     }
 
     @Override

diff --git a/core/src/main/java/org/jruby/ir/IRScope.java b/core/src/main/java/org/jruby/ir/IRScope.java
@@ -58,6 +58,7 @@
  * and so on ...
  */
 public abstract class IRScope implements ParseResult {
+
     private static final Logger LOG = LoggerFactory.getLogger("IRScope");
 
     private static AtomicInteger globalScopeCount = new AtomicInteger();
@@ -139,6 +140,13 @@ public abstract class IRScope implements ParseResult {
 
     private TemporaryVariable yieldClosureVariable;
 
+    // What state is this scope in?
+    enum ScopeState {
+        INIT, INSTRS_CLONED, CFG_BUILT
+    };
+
+    private ScopeState state = ScopeState.INIT;
+
     // Used by cloning code
     protected IRScope(IRScope s, IRScope lexicalParent) {
         this.lexicalParent = lexicalParent;
@@ -163,6 +171,7 @@ protected IRScope(IRScope s, IRScope lexicalParent) {
 
         this.localVars = new HashMap<String, LocalVariable>(s.localVars);
         this.scopeId = globalScopeCount.getAndIncrement();
+        this.state = ScopeState.INIT; // SSS FIXME: Is this correct?
 
         this.executedPasses = new ArrayList<CompilerPass>();
 
@@ -208,6 +217,7 @@ public IRScope(IRManager manager, IRScope lexicalParent, String name,
 
         this.localVars = new HashMap<String, LocalVariable>();
         this.scopeId = globalScopeCount.getAndIncrement();
+        this.state = ScopeState.INIT;
 
         this.executedPasses = new ArrayList<CompilerPass>();
 
@@ -451,6 +461,7 @@ public CFG buildCFG() {
         this.instrList = null;
 
         setCFG(newCFG);
+        this.state = ScopeState.CFG_BUILT;
 
         return newCFG;
     }
@@ -465,6 +476,20 @@ public CFG getCFG() {
 
     @Interp
     protected Instr[] prepareInstructions() {
+        if (getCFG() == null) {
+            int n = instrList.size();
+            Instr[] linearizedInstrArray = instrList.toArray(new Instr[n]);
+            for (int ipc = 0; ipc < n; ipc++) {
+                Instr i = linearizedInstrArray[ipc];
+                i.setIPC(ipc);
+                if (i instanceof LabelInstr) {
+                    ((LabelInstr)i).getLabel().setTargetPC(ipc+1);
+                }
+            }
+
+            return linearizedInstrArray;
+        }
+
         setupLinearization();
 
         boolean simple_method = this instanceof IRMethod;
@@ -603,26 +628,52 @@ protected void initScope(boolean jitMode) {
     }
 
     /** Make version specific to scope which needs it (e.g. Closure vs non-closure). */
-    public InterpreterContext allocateInterpreterContext(Instr[] instructionList) {
-        return new InterpreterContext(this, instructionList);
+    public InterpreterContext allocateInterpreterContext(Instr[] instructionList, boolean rebuild) {
+        return new InterpreterContext(this, instructionList, rebuild);
+    }
+
+    public InterpreterContext prepareForInterpretation() {
+        return prepareForInterpretation(false);
+    }
+
+    protected void cloneInstrs() {
+        if (this.state == ScopeState.INIT) {
+            // Clone instrs before modifying them
+            SimpleCloneInfo cloneInfo = new SimpleCloneInfo(this, false);
+            List<Instr> newInstrList = new ArrayList<Instr>(this.instrList.size());
+            for (Instr instr: this.instrList) {
+                newInstrList.add(instr.clone(cloneInfo));
+            }
+            this.instrList = newInstrList;
+            this.state = ScopeState.INSTRS_CLONED;
+        }
     }
 
     /** Run any necessary passes to get the IR ready for interpretation */
-    public synchronized InterpreterContext prepareForInterpretation() {
-        if (interpreterContext != null) return interpreterContext; // Already prepared
+    public synchronized InterpreterContext prepareForInterpretation(boolean rebuild) {
+        if (interpreterContext != null) {
+            if (!rebuild || getCFG() != null) {
+                return interpreterContext; // Already prepared/rebuilt
+            }
 
-        initScope(false);
+            // If rebuilding, clone instrs before building cfg, running passes, etc.
+            this.cloneInstrs();
+            for (IRClosure cl: getClosures()) {
+                cl.cloneInstrs();
+            }
 
-        // System.out.println("-- passes run for: " + this + " = " + java.util.Arrays.toString(executedPasses.toArray()));
+            // Build CFG, run passes, etc.
+            initScope(false);
 
-        // Always add call protocol instructions now for both interpreter and JIT
-        // since we are removing support for implicit stuff in the interpreter.
-        // When JIT later runs this same pass, it will be a NOP there.
-        if (!isUnsafeScope()) {
-            (new AddCallProtocolInstructions()).run(this);
+            // Always add call protocol instructions now for both interpreter and JIT
+            // since we are removing support for implicit stuff in the interpreter.
+            // When JIT later runs this same pass, it will be a NOP there.
+            if (!isUnsafeScope()) {
+                (new AddCallProtocolInstructions()).run(this);
+            }
         }
 
-        interpreterContext = allocateInterpreterContext(prepareInstructions());
+        interpreterContext = allocateInterpreterContext(prepareInstructions(), rebuild);
 
         return interpreterContext;
     }

diff --git a/core/src/main/java/org/jruby/ir/IRScriptBody.java b/core/src/main/java/org/jruby/ir/IRScriptBody.java
@@ -31,8 +31,8 @@ public void setTopLevelBindingScope(DynamicScope tlbScope) {
     }
 
     @Override
-    public InterpreterContext allocateInterpreterContext(Instr[] instructionList) {
-        return new BeginEndInterpreterContext(this, instructionList);
+    public InterpreterContext allocateInterpreterContext(Instr[] instructionList, boolean rebuild) {
+        return new BeginEndInterpreterContext(this, instructionList, rebuild);
     }
 
     @Override

diff --git a/core/src/main/java/org/jruby/ir/interpreter/BeginEndInterpreterContext.java b/core/src/main/java/org/jruby/ir/interpreter/BeginEndInterpreterContext.java
@@ -14,8 +14,8 @@
 public class BeginEndInterpreterContext extends InterpreterContext {
     private List<IRClosure> beginBlocks;
 
-    public BeginEndInterpreterContext(IRScope scope, Instr[] instructions) {
-        super(scope, instructions);
+    public BeginEndInterpreterContext(IRScope scope, Instr[] instructions, boolean rebuild) {
+        super(scope, instructions, rebuild);
 
         beginBlocks = scope.getBeginBlocks();
     }

diff --git a/core/src/main/java/org/jruby/ir/interpreter/ClosureInterpreterContext.java b/core/src/main/java/org/jruby/ir/interpreter/ClosureInterpreterContext.java
@@ -9,8 +9,8 @@
  * Interpreter knowledge needed to interpret a closure.
  */
 public class ClosureInterpreterContext extends InterpreterContext {
-    public ClosureInterpreterContext(IRClosure scope, Instr[] instructions) {
-        super(scope, instructions);
+    public ClosureInterpreterContext(IRClosure scope, Instr[] instructions, boolean rebuild) {
+        super(scope, instructions, rebuild);
     }
 
     /**

diff --git a/core/src/main/java/org/jruby/ir/interpreter/Interpreter.java b/core/src/main/java/org/jruby/ir/interpreter/Interpreter.java
@@ -17,6 +17,7 @@
 import org.jruby.ir.IRTranslator;
 import org.jruby.ir.operands.IRException;
 import org.jruby.ir.operands.WrappedIRClosure;
+import org.jruby.ir.representations.CFG;
 import org.jruby.ir.runtime.IRBreakJump;
 import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.parser.StaticScope;

diff --git a/core/src/main/java/org/jruby/ir/interpreter/InterpreterContext.java b/core/src/main/java/org/jruby/ir/interpreter/InterpreterContext.java
@@ -19,7 +19,6 @@ public class InterpreterContext {
     private final int temporaryFixnumVariablecount;
     private final int temporaryFloatVariablecount;
 
-
     private final String name;
     private final String fileName;
     private final int lineNumber;
@@ -44,10 +43,18 @@ public class InterpreterContext {
     // View of CFG at time of creating this context.
     private CFG cfg = null;
 
-    public InterpreterContext(IRScope scope, Instr[] instructions) {
+    private int runCount = 0;
+    private boolean rebuilt = false;
+
+    public InterpreterContext(IRScope scope, Instr[] instructions, boolean rebuild) {
         //FIXME: Remove once we conditionally plug in CFG on debug-only
         this.cfg = scope.getCFG();
+        this.rebuilt = rebuild;
+        if (this.rebuilt) {
+            this.runCount = 5;
+        }
 
+/*
         if (scope instanceof IRModuleBody || scope instanceof IRClassBody) {
             engine = BODY_INTERPRETER;
         // ENEBO: Playing with unboxable and subset instruction sets
@@ -56,6 +63,8 @@ public InterpreterContext(IRScope scope, Instr[] instructions) {
         } else {
             engine = DEFAULT_INTERPRETER;
         }
+*/
+        engine = DEFAULT_INTERPRETER;
 
         this.name = scope.getName();
         this.fileName = scope.getFileName();
@@ -75,6 +84,22 @@ public InterpreterContext(IRScope scope, Instr[] instructions) {
         this.receivesKeywordArguments = scope.getFlags().contains(IRFlags.RECEIVES_KEYWORD_ARGS);
     }
 
+    public CFG getCFG() {
+        return this.cfg;
+    }
+
+    public boolean isRebuilt() {
+        return this.rebuilt;
+    }
+
+    public void incrementRunCount() {
+        this.runCount++;
+    }
+
+    public boolean needsRebuilding() {
+        return this.runCount == 20;
+    }
+
     public Object[] allocateTemporaryVariables() {
         return temporaryVariablecount > 0 ? new Object[temporaryVariablecount] : null;
     }

diff --git a/core/src/main/java/org/jruby/ir/interpreter/InterpreterEngine.java b/core/src/main/java/org/jruby/ir/interpreter/InterpreterEngine.java
@@ -41,6 +41,7 @@
 import org.jruby.ir.operands.Bignum;
 import org.jruby.ir.operands.Fixnum;
 import org.jruby.ir.operands.Float;
+import org.jruby.ir.operands.Label;
 import org.jruby.ir.operands.LocalVariable;
 import org.jruby.ir.operands.Operand;
 import org.jruby.ir.operands.Self;
@@ -52,6 +53,8 @@
 import org.jruby.ir.operands.UnboxedFixnum;
 import org.jruby.ir.operands.UnboxedFloat;
 import org.jruby.ir.operands.Variable;
+import org.jruby.ir.runtime.IRBreakJump;
+import org.jruby.ir.runtime.IRReturnJump;
 import org.jruby.ir.runtime.IRRuntimeHelpers;
 import org.jruby.parser.StaticScope;
 import org.jruby.runtime.Block;
@@ -63,6 +66,8 @@
 import org.jruby.runtime.ivars.VariableAccessor;
 import org.jruby.runtime.opto.ConstantCache;
 
+import java.util.Stack;
+
 /**
  * Base full interpreter.  Subclasses can use utility methods here and override what they want.
  */
@@ -115,11 +120,19 @@ public IRubyObject interpret(ThreadContext context, IRubyObject self,
         IRScope scope = currScope.getIRScope();
         boolean      acceptsKeywordArgument = interpreterContext.receivesKeywordArguments();
 
+        Stack<Integer> rescuePCs = null;
+        if (interpreterContext.getCFG() == null) {
+            rescuePCs = new Stack<Integer>();
+        }
+
         // Init profiling this scope
         boolean debug   = IRRuntimeHelpers.isDebug();
         boolean profile = IRRuntimeHelpers.inProfileMode();
         Integer scopeVersion = profile ? Profiler.initProfiling(scope) : 0;
 
+        // Update profile
+        interpreterContext.incrementRunCount();
+
         // Enter the looooop!
         while (ipc < n) {
             Instr instr = instrs[ipc];
@@ -164,7 +177,7 @@ public IRubyObject interpret(ThreadContext context, IRubyObject self,
                             currDynScope = interpreterContext.newDynamicScope(context);
                             context.pushScope(currDynScope);
                         } else {
-                            processBookKeepingOp(context, instr, operation, name, args, self, block, implClass);
+                            processBookKeepingOp(context, instr, operation, name, args, self, block, implClass, rescuePCs);
                         }
                         break;
                     case OTHER_OP:
@@ -176,7 +189,21 @@ public IRubyObject interpret(ThreadContext context, IRubyObject self,
                     extractToMethodToAvoidC2Crash(context, instr, t);
                 }
 
-                ipc = instr.getRPC();
+                if (rescuePCs == null) {
+                    // When CFG is present
+                    ipc = instr.getRPC();
+                } else {
+                    // When CFG is absent
+                    if (rescuePCs.empty()
+                        || (t instanceof IRBreakJump && (instr instanceof BreakInstr))
+                        || (t instanceof IRReturnJump && (instr instanceof NonlocalReturnInstr)))
+                    {
+                        ipc = -1;
+                    } else {
+                        ipc = rescuePCs.pop();
+                    }
+                }
+
                 if (debug) {
                     Interpreter.LOG.info("in : " + interpreterContext.getStaticScope().getIRScope() + ", caught Java throwable: " + t + "; excepting instr: " + instr);
                     Interpreter.LOG.info("ipc for rescuer: " + ipc);
@@ -323,8 +350,16 @@ private static void processCall(ThreadContext context, Instr instr, Operation op
 
     private static void processBookKeepingOp(ThreadContext context, Instr instr, Operation operation,
                                              String name, IRubyObject[] args, IRubyObject self, Block block,
-                                             RubyModule implClass) {
+                                             RubyModule implClass, Stack<Integer> rescuePCs) {
         switch(operation) {
+            case LABEL:
+                break;
+            case EXC_REGION_START:
+                rescuePCs.push(((Label)instr.getOperands()[0]).getTargetPC());
+                break;
+            case EXC_REGION_END:
+                rescuePCs.pop();
+                break;
             case PUSH_FRAME:
                 context.preMethodFrameOnly(implClass, name, self, block);
                 // Only the top-level script scope has PRIVATE visibility.
@@ -392,6 +427,8 @@ private static void processOtherOp(ThreadContext context, Instr instr, Operation
     {
         Object result;
         switch(operation) {
+            case RECV_SELF:
+                break;
             case COPY: {
                 CopyInstr c = (CopyInstr)instr;
                 Operand src = c.getSource();

diff --git a/core/src/main/java/org/jruby/runtime/InterpretedIRBlockBody.java b/core/src/main/java/org/jruby/runtime/InterpretedIRBlockBody.java
@@ -32,8 +32,18 @@ public InterpreterContext ensureInstrsReady() {
             LOG.info(closure.debugOutput());
             displayedCFG = true;
         }
-        // Always prepared in the context of parent scope -- so a null value here is a bug.
-        return closure.getInterpreterContext();
+
+        // Try unsync access first before calling more expensive method for getting IC
+        InterpreterContext ic = closure.getInterpreterContext();
+
+        // Build/rebuild if necessary
+        if (ic == null) {
+            ic = closure.prepareForInterpretation();
+        } else if (ic.needsRebuilding()) {
+            ic = closure.prepareForInterpretation(true);
+        }
+
+        return ic;
     }
 
     protected IRubyObject commonYieldPath(ThreadContext context, IRubyObject[] args, IRubyObject self, Binding binding, Type type, Block block) {