[fastcall] Turn the options pointer to a reference

Refactor the {options} output parameter of the fast callback to a
reference, since it can never be nullptr for functions created with
MakeWithFallbackSupport. This allows embedders to spare the nullptr
check.

Bug: chromium:1052746
Change-Id: I3e22f07af4740ebe8522691da51b6addbc980f24
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2491026Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Auto-Submit: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70706}

include/v8-fast-api-calls.h

@@ -37,12 +37,12 @@
  * declare their method like:
  *
  * \code
- *    void FastMethodWithFallback(int param, FastApiCallbackOptions* options);
+ *    void FastMethodWithFallback(int param, FastApiCallbackOptions& options);
  * \endcode
  *
  * If the callback wants to signal an error condition or to perform an
- * allocation, it must set options->fallback to true and do an early return from
- * the fast method. Then V8 checks the value of options->fallback and if it's
+ * allocation, it must set options.fallback to true and do an early return from
+ * the fast method. Then V8 checks the value of options.fallback and if it's
  * true, falls back to executing the SlowCallback, which is capable of reporting
  * the error (either by throwing a JS exception or logging to the console) or
  * doing the allocation. It's the embedder's responsibility to ensure that the

test/cctest/test-api.cc

@@ -27568,11 +27568,12 @@ DEFINE_OPERATORS_FOR_FLAGS(ApiCheckerResultFlags)
 template <typename Value, typename Impl>
 struct BasicApiChecker {
   static void FastCallback(v8::ApiObject receiver, Value argument,
-                           v8::FastApiCallbackOptions* options) {
+                           v8::FastApiCallbackOptions& options) {
     Impl::FastCallback(receiver, argument, options);
   }
   static void FastCallbackNoFallback(v8::ApiObject receiver, Value argument) {
-    Impl::FastCallback(receiver, argument, nullptr);
+    v8::FastApiCallbackOptions options;
+    Impl::FastCallback(receiver, argument, options);
   }
   static void SlowCallback(const v8::FunctionCallbackInfo<v8::Value>& info) {
     Impl::SlowCallback(info);
@@ -27622,10 +27623,10 @@ struct ApiNumberChecker : BasicApiChecker<T, ApiNumberChecker<T>> {
         args_count_(args_count) {}
 
   static void FastCallback(v8::ApiObject receiver, T argument,
-                           v8::FastApiCallbackOptions* options) {
+                           v8::FastApiCallbackOptions& options) {
     v8::Object* receiver_obj = reinterpret_cast<v8::Object*>(&receiver);
     if (!IsValidUnwrapObject(receiver_obj)) {
-      options->fallback = 1;
+      options.fallback = 1;
       return;
     }
     ApiNumberChecker<T>* receiver_ptr =
@@ -27638,8 +27639,8 @@ struct ApiNumberChecker : BasicApiChecker<T, ApiNumberChecker<T>> {
       // the default behavior expected from the embedder. The value is checked
       // against after loading it from a stack slot, as defined in
       // EffectControlLinearizer::LowerFastApiCall.
-      CHECK_EQ(options->fallback, 0);
-      options->fallback = 1;
+      CHECK_EQ(options.fallback, 0);
+      options.fallback = 1;
     }
   }
 
@@ -27674,7 +27675,7 @@ struct ApiNumberChecker : BasicApiChecker<T, ApiNumberChecker<T>> {
 struct UnexpectedObjectChecker
     : BasicApiChecker<v8::ApiObject, UnexpectedObjectChecker> {
   static void FastCallback(v8::ApiObject receiver, v8::ApiObject argument,
-                           v8::FastApiCallbackOptions* options) {
+                           v8::FastApiCallbackOptions& options) {
     v8::Object* receiver_obj = reinterpret_cast<v8::Object*>(&receiver);
     UnexpectedObjectChecker* receiver_ptr =
         GetInternalField<UnexpectedObjectChecker, kV8WrapperObjectIndex>(