Leaving a generator via an exception causes it to close

src/arm/full-codegen-arm.cc

Index: src/arm/full-codegen-arm.cc
diff --git a/src/arm/full-codegen-arm.cc b/src/arm/full-codegen-arm.cc
index f4938a72975ee612de115649a93687043760f372..4491eda9fbd8f4defe088a3b08b7249dbd11b644 100644
--- a/src/arm/full-codegen-arm.cc
+++ b/src/arm/full-codegen-arm.cc
@@ -2234,15 +2234,6 @@ void FullCodeGenerator::EmitGeneratorResume(Expression *generator,
   VisitForAccumulatorValue(value);
   __ pop(r1);
 
-  // Check generator state.
-  Label wrong_state, closed_state, done;
-  __ ldr(r3, FieldMemOperand(r1, JSGeneratorObject::kContinuationOffset));
-  STATIC_ASSERT(JSGeneratorObject::kGeneratorExecuting < 0);
-  STATIC_ASSERT(JSGeneratorObject::kGeneratorClosed == 0);
-  __ cmp(r3, Operand(Smi::FromInt(0)));
-  __ b(eq, &closed_state);
-  __ b(lt, &wrong_state);
-
   // Load suspended function and context.
   __ ldr(cp, FieldMemOperand(r1, JSGeneratorObject::kContextOffset));
   __ ldr(r4, FieldMemOperand(r1, JSGeneratorObject::kFunctionOffset));
@@ -2265,7 +2256,7 @@ void FullCodeGenerator::EmitGeneratorResume(Expression *generator,
 
   // Enter a new JavaScript frame, and initialize its slots as they were when
   // the generator was suspended.
-  Label resume_frame;
+  Label resume_frame, done;
   __ bind(&push_frame);
   __ bl(&resume_frame);
   __ jmp(&done);
@@ -2325,26 +2316,6 @@ void FullCodeGenerator::EmitGeneratorResume(Expression *generator,
   // Not reached: the runtime call returns elsewhere.
   __ stop("not-reached");
 
-  // Reach here when generator is closed.
-  __ bind(&closed_state);
-  if (resume_mode == JSGeneratorObject::NEXT) {
-    // Return completed iterator result when generator is closed.
-    __ LoadRoot(r2, Heap::kUndefinedValueRootIndex);
-    __ push(r2);
-    // Pop value from top-of-stack slot; box result into result register.
-    EmitCreateIteratorResult(true);
-  } else {
-    // Throw the provided value.
-    __ push(r0);
-    __ CallRuntime(Runtime::kThrow, 1);
-  }
-  __ jmp(&done);
-
-  // Throw error if we attempt to operate on a running generator.
-  __ bind(&wrong_state);
-  __ push(r1);
-  __ CallRuntime(Runtime::kThrowGeneratorStateError, 1);
-
   __ bind(&done);
   context()->Plug(result_register());
 }