From 2927ab4482133aca3e059015b6057a9ea7886d97 Mon Sep 17 00:00:00 2001
From: Haled Odat <8566042+HalidOdat@users.noreply.github.com>
Date: Wed, 12 Jul 2023 21:22:53 +0200
Subject: [PATCH] Remove yield  flag

---
 boa_engine/src/vm/call_frame/mod.rs             |  3 ---
 boa_engine/src/vm/mod.rs                        | 14 +++++++-------
 boa_engine/src/vm/opcode/await_stm/mod.rs       |  3 +--
 boa_engine/src/vm/opcode/generator/yield_stm.rs |  5 ++---
 4 files changed, 10 insertions(+), 15 deletions(-)

diff --git a/boa_engine/src/vm/call_frame/mod.rs b/boa_engine/src/vm/call_frame/mod.rs
index b2315f34bc7..470a26581b8 100644
--- a/boa_engine/src/vm/call_frame/mod.rs
+++ b/boa_engine/src/vm/call_frame/mod.rs
@@ -19,8 +19,6 @@ pub struct CallFrame {
     pub(crate) pc: u32,
     pub(crate) fp: u32,
     pub(crate) env_fp: u32,
-    #[unsafe_ignore_trace]
-    pub(crate) r#yield: bool,
     // Tracks the number of environments in environment entry.
     // On abrupt returns this is used to decide how many environments need to be pop'ed.
     pub(crate) argument_count: u32,
@@ -65,7 +63,6 @@ impl CallFrame {
             pc: 0,
             fp: 0,
             env_fp: 0,
-            r#yield: false,
             argument_count: 0,
             generator_resume_kind: GeneratorResumeKind::Normal,
             promise_capability: None,
diff --git a/boa_engine/src/vm/mod.rs b/boa_engine/src/vm/mod.rs
index 9962270fe5b..235c01bc398 100644
--- a/boa_engine/src/vm/mod.rs
+++ b/boa_engine/src/vm/mod.rs
@@ -154,6 +154,7 @@ pub(crate) enum CompletionType {
     Normal,
     Return,
     Throw,
+    Yield,
 }
 
 impl Context<'_> {
@@ -290,6 +291,11 @@ impl Context<'_> {
                 Ok(CompletionType::Throw) => {
                     break CompletionType::Throw;
                 }
+                // Early return immediately.
+                Ok(CompletionType::Yield) => {
+                    let result = self.vm.pop();
+                    return CompletionRecord::Return(result);
+                }
                 Err(err) => {
                     #[cfg(feature = "fuzz")]
                     {
@@ -327,13 +333,6 @@ impl Context<'_> {
             }
         };
 
-        // Early return immediately after loop.
-        if self.vm.frame().r#yield {
-            self.vm.frame_mut().r#yield = false;
-            let result = self.vm.pop();
-            return CompletionRecord::Return(result);
-        }
-
         #[cfg(feature = "trace")]
         if self.vm.trace {
             println!("\nStack:");
@@ -385,6 +384,7 @@ impl Context<'_> {
                         .expect("cannot fail per spec");
                     self.vm.err = Some(err);
                 }
+                CompletionType::Yield => unreachable!(),
             }
         } else if let Some(generator_object) = self.vm.frame().async_generator.clone() {
             // Step 3.e-g in [AsyncGeneratorStart](https://tc39.es/ecma262/#sec-asyncgeneratorstart)
diff --git a/boa_engine/src/vm/opcode/await_stm/mod.rs b/boa_engine/src/vm/opcode/await_stm/mod.rs
index 6296da9294a..25c92b767de 100644
--- a/boa_engine/src/vm/opcode/await_stm/mod.rs
+++ b/boa_engine/src/vm/opcode/await_stm/mod.rs
@@ -126,7 +126,6 @@ impl Operation for Await {
         );
 
         context.vm.push(JsValue::undefined());
-        context.vm.frame_mut().r#yield = true;
-        Ok(CompletionType::Return)
+        Ok(CompletionType::Yield)
     }
 }
diff --git a/boa_engine/src/vm/opcode/generator/yield_stm.rs b/boa_engine/src/vm/opcode/generator/yield_stm.rs
index 8f545de58da..708e724d78e 100644
--- a/boa_engine/src/vm/opcode/generator/yield_stm.rs
+++ b/boa_engine/src/vm/opcode/generator/yield_stm.rs
@@ -15,9 +15,8 @@ impl Operation for GeneratorYield {
     const NAME: &'static str = "GeneratorYield";
     const INSTRUCTION: &'static str = "INST - GeneratorYield";
 
-    fn execute(context: &mut Context<'_>) -> JsResult<CompletionType> {
-        context.vm.frame_mut().r#yield = true;
-        Ok(CompletionType::Return)
+    fn execute(_context: &mut Context<'_>) -> JsResult<CompletionType> {
+        Ok(CompletionType::Yield)
     }
 }