Throw a TypeError when calling "next" method of a newly created generator with a value

src/mips/full-codegen-mips.cc

Index: src/mips/full-codegen-mips.cc
diff --git a/src/mips/full-codegen-mips.cc b/src/mips/full-codegen-mips.cc
index 1303fba5385530dc80fbea18f3ce96653cc1565b..2c4b29aaae24ae5877ba7f02fb97763983e5db6f 100644
--- a/src/mips/full-codegen-mips.cc
+++ b/src/mips/full-codegen-mips.cc
@@ -2017,6 +2017,10 @@ void FullCodeGenerator::VisitYield(Yield* expr) {
       ASSERT(continuation.pos() > 0 && Smi::IsValid(continuation.pos()));
       __ li(a1, Operand(Smi::FromInt(continuation.pos())));
       __ sw(a1, FieldMemOperand(v0, JSGeneratorObject::kContinuationOffset));
+      if (expr->yield_kind() == Yield::INITIAL) {
+        __ sw(a1,
+              FieldMemOperand(v0, JSGeneratorObject::kSuspendedStartOffset));
+      }
       __ sw(cp, FieldMemOperand(v0, JSGeneratorObject::kContextOffset));
       __ mov(a1, cp);
       __ RecordWriteField(v0, JSGeneratorObject::kContextOffset, a1, a2,
@@ -2146,12 +2150,16 @@ void FullCodeGenerator::EmitGeneratorResume(Expression *generator,
   __ pop(a1);
 
   // Check generator state.
-  Label wrong_state, closed_state, done;
+  Label wrong_state, closed_state, suspended_start_state, resume_state, done;
   __ lw(a3, FieldMemOperand(a1, JSGeneratorObject::kContinuationOffset));
   STATIC_ASSERT(JSGeneratorObject::kGeneratorExecuting < 0);
   STATIC_ASSERT(JSGeneratorObject::kGeneratorClosed == 0);
   __ Branch(&closed_state, eq, a3, Operand(zero_reg));
   __ Branch(&wrong_state, lt, a3, Operand(zero_reg));
+  __ lw(a2, FieldMemOperand(a1, JSGeneratorObject::kSuspendedStartOffset));
+  __ Branch(&suspended_start_state, eq, a3, Operand(a2));
+
+  __ bind(&resume_state);
 
   // Load suspended function and context.
   __ lw(cp, FieldMemOperand(a1, JSGeneratorObject::kContextOffset));
@@ -2224,6 +2232,30 @@ void FullCodeGenerator::EmitGeneratorResume(Expression *generator,
   // Not reached: the runtime call returns elsewhere.
   __ stop("not-reached");
 
+  // Throw the provided value.
+  Label throw_provided_value;
+  __ bind(&throw_provided_value);
+  if (resume_mode != JSGeneratorObject::NEXT) {
+    __ push(a0);
+    __ CallRuntime(Runtime::kThrow, 1);
+    __ Branch(&done);
+  }
+
+  // Reach here when calling initial resume to a generator.
+  __ bind(&suspended_start_state);
+  if (resume_mode == JSGeneratorObject::NEXT) {
+    // When value is provided and it is not undefined, throw error.
+    __ LoadRoot(a2, Heap::kUndefinedValueRootIndex);
+    __ Branch(&resume_state, eq, a0, Operand(a2));
+    __ CallRuntime(Runtime::kThrowGeneratorStartError, 0);
+    __ Branch(&done);
+  } else {
+      // Make generator's state to "closed".
+      __ li(a2, Operand(Smi::FromInt(JSGeneratorObject::kGeneratorClosed)));
+      __ sw(a2, FieldMemOperand(a1, JSGeneratorObject::kContinuationOffset));
+    __ Branch(&throw_provided_value);
+  }
+
   // Reach here when generator is closed.
   __ bind(&closed_state);
   if (resume_mode == JSGeneratorObject::NEXT) {
@@ -2232,12 +2264,10 @@ void FullCodeGenerator::EmitGeneratorResume(Expression *generator,
     __ push(a2);
     // Pop value from top-of-stack slot; box result into result register.
     EmitCreateIteratorResult(true);
+    __ Branch(&done);
   } else {
-    // Throw the provided value.
-    __ push(a0);
-    __ CallRuntime(Runtime::kThrow, 1);
+    __ Branch(&throw_provided_value);
   }
-  __ jmp(&done);
 
   // Throw error if we attempt to operate on a running generator.
   __ bind(&wrong_state);