Switch full-codegen from StackHandlers to handler table.

src/runtime/runtime-generator.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/arguments.h"
 #include "src/frames-inl.h"
 #include "src/runtime/runtime-utils.h"
 
@@ skipping 13 matching lines @@
   if (frame->IsConstructor()) {
     generator = handle(JSGeneratorObject::cast(frame->receiver()));
   } else {
     generator = isolate->factory()->NewJSGeneratorObject(function);
   }
   generator->set_function(*function);
   generator->set_context(Context::cast(frame->context()));
   generator->set_receiver(frame->receiver());
   generator->set_continuation(0);
   generator->set_operand_stack(isolate->heap()->empty_fixed_array());
-  generator->set_stack_handler_index(-1);
 
   return *generator;
 }
 
 
 RUNTIME_FUNCTION(Runtime_SuspendJSGeneratorObject) {
   HandleScope handle_scope(isolate);
-  DCHECK(args.length() == 1);
+  DCHECK(args.length() == 1 || args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSGeneratorObject, generator_object, 0);
 
   JavaScriptFrameIterator stack_iterator(isolate);
   JavaScriptFrame* frame = stack_iterator.frame();
   RUNTIME_ASSERT(frame->function()->shared()->is_generator());
   DCHECK_EQ(frame->function(), generator_object->function());
 
   // The caller should have saved the context and continuation already.
   DCHECK_EQ(generator_object->context(), Context::cast(frame->context()));
   DCHECK_LT(0, generator_object->continuation());
 
   // We expect there to be at least two values on the operand stack: the return
-  // value of the yield expression, and the argument to this runtime call.
+  // value of the yield expression, and the arguments to this runtime call.
   // Neither of those should be saved.
   int operands_count = frame->ComputeOperandsCount();
-  DCHECK_GE(operands_count, 2);
-  operands_count -= 2;
+  DCHECK_GE(operands_count, 1 + args.length());
+  operands_count -= 1 + args.length();
+
+  // Second argument indicates that we need to patch the handler table because
+  // a delegating yield introduced a try-catch statement at expression level,
+  // hence the operand count was off when we statically computed it.
+  // TODO(mstarzinger): This special case disappears with do-expressions.
+  if (args.length() == 2) {
+    CONVERT_SMI_ARG_CHECKED(handler_index, 1);
+    Handle<Code> code(frame->unchecked_code());
+    Handle<HandlerTable> table(HandlerTable::cast(code->handler_table()));
+    int handler_depth = operands_count - TryBlockConstant::kElementCount;
+    table->SetRangeDepth(handler_index, handler_depth);
+  }
 
   if (operands_count == 0) {
     // Although it's semantically harmless to call this function with an
     // operands_count of zero, it is also unnecessary.
     DCHECK_EQ(generator_object->operand_stack(),
               isolate->heap()->empty_fixed_array());
-    DCHECK_EQ(generator_object->stack_handler_index(), -1);
-    // If there are no operands on the stack, there shouldn't be a handler
-    // active either.
-    DCHECK(!frame->HasHandler());
   } else {
-    int stack_handler_index = -1;
     Handle<FixedArray> operand_stack =
         isolate->factory()->NewFixedArray(operands_count);
-    frame->SaveOperandStack(*operand_stack, &stack_handler_index);
+    frame->SaveOperandStack(*operand_stack);
     generator_object->set_operand_stack(*operand_stack);
-    generator_object->set_stack_handler_index(stack_handler_index);
   }
 
   return isolate->heap()->undefined_value();
 }
 
 
 // Note that this function is the slow path for resuming generators.  It is only
 // called if the suspended activation had operands on the stack, stack handlers
 // needing rewinding, or if the resume should throw an exception.  The fast path
 // is handled directly in FullCodeGenerator::EmitGeneratorResume(), which is
@@ skipping 21 matching lines @@
   frame->set_pc(pc + offset);
   if (FLAG_enable_ool_constant_pool) {
     frame->set_constant_pool(
         generator_object->function()->code()->constant_pool());
   }
   generator_object->set_continuation(JSGeneratorObject::kGeneratorExecuting);
 
   FixedArray* operand_stack = generator_object->operand_stack();
   int operands_count = operand_stack->length();
   if (operands_count != 0) {
-    frame->RestoreOperandStack(operand_stack,
-                               generator_object->stack_handler_index());
+    frame->RestoreOperandStack(operand_stack);
     generator_object->set_operand_stack(isolate->heap()->empty_fixed_array());
-    generator_object->set_stack_handler_index(-1);
   }
 
   JSGeneratorObject::ResumeMode resume_mode =
       static_cast<JSGeneratorObject::ResumeMode>(resume_mode_int);
   switch (resume_mode) {
     case JSGeneratorObject::NEXT:
       return value;
     case JSGeneratorObject::THROW:
       return isolate->Throw(value);
   }
@@ skipping 86 matching lines @@
   return NULL;
 }
 
 
 RUNTIME_FUNCTION(Runtime_GeneratorThrow) {
   UNREACHABLE();  // Optimization disabled in SetUpGenerators().
   return NULL;
 }
 }
 }  // namespace v8::internal