From 9fe38245b24dcf864c9c6aff8dce597819566d0b Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Tue, 26 Sep 2023 16:41:42 +0200
Subject: [PATCH] LibJS: Move bytecode interpreter's inner loop to its own
 function

---
 .../Libraries/LibJS/Bytecode/Interpreter.cpp  | 36 +++++++++++--------
 .../Libraries/LibJS/Bytecode/Interpreter.h    |  2 ++
 2 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/Userland/Libraries/LibJS/Bytecode/Interpreter.cpp b/Userland/Libraries/LibJS/Bytecode/Interpreter.cpp
index 848659a5ad..9fb98b56b9 100644
--- a/Userland/Libraries/LibJS/Bytecode/Interpreter.cpp
+++ b/Userland/Libraries/LibJS/Bytecode/Interpreter.cpp
@@ -161,22 +161,8 @@ ThrowCompletionOr<Value> Interpreter::run(SourceTextModule& module)
     return js_undefined();
 }
 
-Interpreter::ValueAndFrame Interpreter::run_and_return_frame(Executable& executable, BasicBlock const* entry_point, CallFrame* in_frame)
+void Interpreter::run_bytecode()
 {
-    dbgln_if(JS_BYTECODE_DEBUG, "Bytecode::Interpreter will run unit {:p}", &executable);
-
-    TemporaryChange restore_executable { m_current_executable, &executable };
-    TemporaryChange restore_saved_jump { m_scheduled_jump, static_cast<BasicBlock const*>(nullptr) };
-
-    VERIFY(!vm().execution_context_stack().is_empty());
-
-    TemporaryChange restore_current_block { m_current_block, entry_point ?: executable.basic_blocks.first() };
-
-    if (in_frame)
-        push_call_frame(in_frame, executable.number_of_registers);
-    else
-        push_call_frame(make<CallFrame>(), executable.number_of_registers);
-
     for (;;) {
         auto pc = InstructionStreamIterator { m_current_block->instruction_stream(), m_current_executable };
         TemporaryChange temp_change { m_pc, Optional<InstructionStreamIterator&>(pc) };
@@ -185,6 +171,7 @@ Interpreter::ValueAndFrame Interpreter::run_and_return_frame(Executable& executa
         bool will_jump = false;
         bool will_return = false;
         bool will_yield = false;
+
         while (!pc.at_end()) {
             auto& instruction = *pc;
             auto ran_or_error = instruction.execute(*this);
@@ -260,6 +247,25 @@ Interpreter::ValueAndFrame Interpreter::run_and_return_frame(Executable& executa
         if (will_return)
             break;
     }
+}
+
+Interpreter::ValueAndFrame Interpreter::run_and_return_frame(Executable& executable, BasicBlock const* entry_point, CallFrame* in_frame)
+{
+    dbgln_if(JS_BYTECODE_DEBUG, "Bytecode::Interpreter will run unit {:p}", &executable);
+
+    TemporaryChange restore_executable { m_current_executable, &executable };
+    TemporaryChange restore_saved_jump { m_scheduled_jump, static_cast<BasicBlock const*>(nullptr) };
+
+    VERIFY(!vm().execution_context_stack().is_empty());
+
+    TemporaryChange restore_current_block { m_current_block, entry_point ?: executable.basic_blocks.first() };
+
+    if (in_frame)
+        push_call_frame(in_frame, executable.number_of_registers);
+    else
+        push_call_frame(make<CallFrame>(), executable.number_of_registers);
+
+    run_bytecode();
 
     dbgln_if(JS_BYTECODE_DEBUG, "Bytecode::Interpreter did run unit {:p}", &executable);
 
diff --git a/Userland/Libraries/LibJS/Bytecode/Interpreter.h b/Userland/Libraries/LibJS/Bytecode/Interpreter.h
index fe9843494d..eae8bf7748 100644
--- a/Userland/Libraries/LibJS/Bytecode/Interpreter.h
+++ b/Userland/Libraries/LibJS/Bytecode/Interpreter.h
@@ -92,6 +92,8 @@ public:
     void visit_edges(Cell::Visitor&);
 
 private:
+    void run_bytecode();
+
     CallFrame& call_frame()
     {
         return m_call_frames.last().visit([](auto& x) -> CallFrame& { return *x; });