[type profile] Collect return types.

src/interpreter/bytecode-generator.cc

 // Copyright 2015 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/interpreter/bytecode-generator.h"
 
 #include "src/ast/compile-time-value.h"
 #include "src/ast/scopes.h"
 #include "src/builtins/builtins-constructor.h"
 #include "src/code-stubs.h"
@@ skipping 1073 matching lines @@
   execution_control()->Continue(stmt->target());
 }
 
 void BytecodeGenerator::VisitBreakStatement(BreakStatement* stmt) {
   builder()->SetStatementPosition(stmt);
   execution_control()->Break(stmt->target());
 }
 
 void BytecodeGenerator::VisitReturnStatement(ReturnStatement* stmt) {
   builder()->SetStatementPosition(stmt);
+
+  Register position;
+  Register name;
+  if (stmt->HasTypeProfileSlot()) {
+    position = register_allocator()->NewRegister();
+
+    builder()
+        ->LoadLiteral(Smi::FromInt(stmt->position()))
+        .StoreAccumulatorInRegister(position);

[rmcilroy, 2017/03/20 10:02:46]

Any reason you need to store position as a register? You could just make it a
kUImm or kImm operand type and store it directly in the bytecode.

[Franzi, 2017/03/20 15:38:39]

Done. Using kImm because for the global(?) return the position is -1. 

+
+    name = register_allocator()->NewRegister();
+
+    if (stmt->expression()->IsVariableProxy()) {
+      builder()
+          ->LoadLiteral(
+              stmt->expression()->AsVariableProxy()->var()->raw_name())
+          .StoreAccumulatorInRegister(name);
+    } else {
+      // Use a dummy string for now.
+      builder()
+          ->LoadLiteral(ast_string_constants()->return_string())
+          .StoreAccumulatorInRegister(name);
+    }

[rmcilroy, 2017/03/20 10:02:46]

As I remember, the plan was to remove the need for the name operand once the
source position was added. Could you do that here to avoid needing additional
logic to get the name for return statements?

[Franzi, 2017/03/20 15:38:39]

Done.

+  }
+
   VisitForAccumulatorValue(stmt->expression());
 
+  if (stmt->HasTypeProfileSlot()) {
+    FeedbackSlot collect_type_feedback_slot = stmt->TypeProfileSlot();
+    builder()->CollectTypeProfile(position, name,
+                                  feedback_index(collect_type_feedback_slot));
+  }
+
   if (stmt->is_async_return()) {
     execution_control()->AsyncReturnAccumulator();
   } else {
     execution_control()->ReturnAccumulator();
   }
 }
 
 void BytecodeGenerator::VisitWithStatement(WithStatement* stmt) {
   builder()->SetStatementPosition(stmt);
   VisitForAccumulatorValue(stmt->expression());
@@ skipping 1099 matching lines @@
   Register object, key;
   RegisterList super_property_args;
   const AstRawString* name;
 
   // Left-hand side can only be a property, a global or a variable slot.
   Property* property = expr->target()->AsProperty();
   LhsKind assign_type = Property::GetAssignType(property);
 
   // Evaluate LHS expression.
   Register lhs_name;
+  Register position;
+
   if (expr->HasTypeProfileSlot()) {
     lhs_name = register_allocator()->NewRegister();
+    position = register_allocator()->NewRegister();
+
+    builder()
+        ->LoadLiteral(Smi::FromInt(expr->position()))
+        .StoreAccumulatorInRegister(position);
   }
 
   switch (assign_type) {
     case VARIABLE:
       if (expr->HasTypeProfileSlot()) {
         builder()
             ->LoadLiteral(expr->target()->AsVariableProxy()->var()->raw_name())
             .StoreAccumulatorInRegister(lhs_name);
       }
       // Nothing to do to evaluate variable assignment LHS.
@@ skipping 124 matching lines @@
     }
     case KEYED_SUPER_PROPERTY: {
       builder()
           ->StoreAccumulatorInRegister(super_property_args[3])
           .CallRuntime(StoreKeyedToSuperRuntimeId(), super_property_args);
       break;
     }
   }
 
   // Value is in accumulator.
-  if (expr->HasTypeProfileSlot()) {
+  if (false && expr->HasTypeProfileSlot()) {

[Michael Starzinger, 2017/03/20 09:29:26]

nit: Looks like a left-over. If it is intentional then please leave a TODO here
explaining why and how long this is intended to be dead code.

[Franzi, 2017/03/20 15:38:39]

Done.

     FeedbackSlot collect_type_feedback_slot = expr->TypeProfileSlot();
 
-    builder()->CollectTypeProfile(lhs_name,
+    builder()->CollectTypeProfile(position, lhs_name,
                                   feedback_index(collect_type_feedback_slot));
   }
 }
 
 void BytecodeGenerator::VisitYield(Yield* expr) {
   builder()->SetExpressionPosition(expr);
   Register value = VisitForRegisterValue(expr->expression());
 
   Register generator = VisitForRegisterValue(expr->generator_object());
 
@@ skipping 1144 matching lines @@
 }
 
 Runtime::FunctionId BytecodeGenerator::StoreKeyedToSuperRuntimeId() {
   return is_strict(language_mode()) ? Runtime::kStoreKeyedToSuper_Strict
                                     : Runtime::kStoreKeyedToSuper_Sloppy;
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8