From cbc0f9fd974de2e2435ac98dd83c4b2ad96f75c1 Mon Sep 17 00:00:00 2001
From: Dan Minor <dminor@mozilla.com>
Date: Thu, 14 Dec 2023 17:58:45 +0000
Subject: [PATCH] Bug 1800724 - Use DecoratorEmitter::emitCallExtraInitializers
 in BytecodeEmitter; r=arai

Differential Revision: https://phabricator.services.mozilla.com/D195924
---
 js/src/frontend/BytecodeEmitter.cpp                |  5 +++++
 js/src/frontend/DecoratorEmitter.cpp               | 13 ++++++++-----
 js/src/jit-test/tests/decorators/addInitializer.js |  6 +++++-
 3 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/js/src/frontend/BytecodeEmitter.cpp b/js/src/frontend/BytecodeEmitter.cpp
index e957c7dabed3..28f4681d9e3f 100644
--- a/js/src/frontend/BytecodeEmitter.cpp
+++ b/js/src/frontend/BytecodeEmitter.cpp
@@ -10755,6 +10755,11 @@ bool BytecodeEmitter::emitInitializeInstanceMembers(
       return false;
     }
     // 5. Return unused.
+
+    if (!de.emitCallExtraInitializers(TaggedParserAtomIndex::WellKnown::
+                                          dot_instanceExtraInitializers_())) {
+      return false;
+    }
 #endif
   }
   return true;
diff --git a/js/src/frontend/DecoratorEmitter.cpp b/js/src/frontend/DecoratorEmitter.cpp
index 2e1f6c0ffb83..77492706b984 100644
--- a/js/src/frontend/DecoratorEmitter.cpp
+++ b/js/src/frontend/DecoratorEmitter.cpp
@@ -812,8 +812,14 @@ bool DecoratorEmitter::emitInitializeFieldOrAccessor() {
 
 bool DecoratorEmitter::emitCallExtraInitializers(
     TaggedParserAtomIndex extraInitializers) {
+  // Support for static and class extra initializers will be added in
+  // bug 1868220 and bug 1868221.
+  MOZ_ASSERT(
+      extraInitializers ==
+      TaggedParserAtomIndex::WellKnown::dot_instanceExtraInitializers_());
+
   if (!bce_->emitGetName(extraInitializers)) {
-    //              [stack] ARRAY
+    //          [stack] ARRAY
     return false;
   }
 
@@ -834,9 +840,6 @@ bool DecoratorEmitter::emitCallExtraInitializers(
   }
 
   InternalWhileEmitter wh(bce_);
-  // At this point, we have no context to determine offsets in the
-  // code for this while statement. Ideally, it would correspond to
-  // the field we're initializing.
   if (!wh.emitCond()) {
     //          [stack] ARRAY LENGTH INDEX
     return false;
@@ -886,7 +889,7 @@ bool DecoratorEmitter::emitCallExtraInitializers(
 
   // Callee is always internal function.
   if (!bce_->emitCall(JSOp::CallIgnoresRv, 0)) {
-    //            [stack] ARRAY LENGTH INDEX INITIALIZER THIS RVAL
+    //            [stack] ARRAY LENGTH INDEX RVAL
     return false;
   }
 
diff --git a/js/src/jit-test/tests/decorators/addInitializer.js b/js/src/jit-test/tests/decorators/addInitializer.js
index 22cc1a3ad70d..58b5c32b2d5f 100644
--- a/js/src/jit-test/tests/decorators/addInitializer.js
+++ b/js/src/jit-test/tests/decorators/addInitializer.js
@@ -1,6 +1,8 @@
 // |jit-test| skip-if: !getBuildConfiguration("decorators")
 load(libdir + "asserts.js");
 
+let extraInitializerCalled = {};
+
 function checkDecoratorContext(kind, isPrivate, isStatic, name) {
   return function (value, context) {
     if (kind == "field") {
@@ -16,7 +18,7 @@ function checkDecoratorContext(kind, isPrivate, isStatic, name) {
     assertEq(context.static, isStatic);
     assertEq(context.name, name);
     assertEq(typeof context.addInitializer, "function");
-    context.addInitializer(() => {});
+    context.addInitializer(() => {extraInitializerCalled[context.name] = true;});
     // return undefined
   }
 }
@@ -27,3 +29,5 @@ class C {
 }
 
 let c = new C();
+assertEq(extraInitializerCalled["x"], true);
+assertEq(extraInitializerCalled["y accessor storage"], true);