[Interpreter] Handle various generator intrinsics

src/interpreter/interpreter-intrinsics-generator.cc

Index: src/interpreter/interpreter-intrinsics-generator.cc
diff --git a/src/interpreter/interpreter-intrinsics-generator.cc b/src/interpreter/interpreter-intrinsics-generator.cc
index d9ca1e21eea27d57251adbd735ba4f6be0a56de4..6c8bb1390a1562b7f56ec5682f7f032d4c3163d4 100644
--- a/src/interpreter/interpreter-intrinsics-generator.cc
+++ b/src/interpreter/interpreter-intrinsics-generator.cc
@@ -405,6 +405,35 @@ Node* IntrinsicsGenerator::CreateJSGeneratorObject(Node* input, Node* arg_count,
                                 Builtins::kCreateGeneratorObject);
 }
 
+Node* IntrinsicsGenerator::GeneratorGetContext(Node* args_reg, Node* arg_count,
+                                               Node* context) {
+  Node* generator = __ LoadRegister(args_reg);
+  Node* const value =
+      __ LoadObjectField(generator, JSGeneratorObject::kContextOffset);

[rmcilroy, 2017/05/17 14:48:28]

Maybe there is a case for having a LoadObjectField bytecode (which takes the
object in the accumulator and the offset as an operand) now which could be used
to implement all three of these intrinsics. WDYT?

[adamk, 2017/05/17 17:35:31]

I like this idea, I was curious why we didn't have something like this when I
started looking at generators last week. But I don't think it needs to hold up
this CL.

[mvstanton, 2017/05/18 10:00:59]

I'm happy to take a run at it. There are probably other cases to plug in
LoadObjectField too. It should make the bytecode smaller, right? (tryin' to
motivate myself :D)

+
+  return value;
+}
+
+Node* IntrinsicsGenerator::GeneratorGetInputOrDebugPos(Node* args_reg,
+                                                       Node* arg_count,
+                                                       Node* context) {
+  Node* generator = __ LoadRegister(args_reg);
+  Node* const value =
+      __ LoadObjectField(generator, JSGeneratorObject::kInputOrDebugPosOffset);
+
+  return value;
+}
+
+Node* IntrinsicsGenerator::GeneratorGetResumeMode(Node* args_reg,
+                                                  Node* arg_count,
+                                                  Node* context) {
+  Node* generator = __ LoadRegister(args_reg);
+  Node* const value =
+      __ LoadObjectField(generator, JSGeneratorObject::kResumeModeOffset);
+
+  return value;
+}
+
 Node* IntrinsicsGenerator::AsyncGeneratorReject(Node* input, Node* arg_count,
                                                 Node* context) {
   return IntrinsicAsBuiltinCall(input, context,