From 21a67c5c31cbb695d14ba2fc50e18172f8ac557d Mon Sep 17 00:00:00 2001
From: Ryan Macnak <rmacnak@google.com>
Date: Tue, 31 Mar 2026 08:38:50 -0700
Subject: [PATCH] [vm] Flatten stub code handle list.

TEST=ci
Change-Id: I852120f3af711f385534e5d1b007705fb3aec078
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/491684
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
---
 runtime/vm/stub_code.cc | 40 +++++++++++++++++++---------------------
 runtime/vm/stub_code.h  | 19 ++++++-------------
 2 files changed, 25 insertions(+), 34 deletions(-)

diff --git a/runtime/vm/stub_code.cc b/runtime/vm/stub_code.cc
index 066f5b6fed6..7961702dddd 100644
--- a/runtime/vm/stub_code.cc
+++ b/runtime/vm/stub_code.cc
@@ -31,16 +31,7 @@ DEFINE_FLAG(bool,
             "Generate probe points for installation of user space probes");
 #endif
 
-StubCode::StubCodeEntry StubCode::entries_[kNumStubEntries] = {
-#if defined(DART_PRECOMPILED_RUNTIME)
-#define STUB_CODE_DECLARE(name) {nullptr, #name},
-#else
-#define STUB_CODE_DECLARE(name)                                                \
-  {nullptr, #name, &compiler::StubCodeCompiler::Generate##name##Stub},
-#endif
-    VM_STUB_CODE_LIST(STUB_CODE_DECLARE)
-#undef STUB_CODE_DECLARE
-};
+Code* StubCode::handles_[kNumStubEntries] = {nullptr};
 AcqRelAtomic<bool> StubCode::initialized_ = {false};
 
 #if defined(DART_PRECOMPILED_RUNTIME)
@@ -55,17 +46,24 @@ void StubCode::Init() {
   compiler::ObjectPoolBuilder object_pool_builder;
 
   // Generate all the stubs.
-  for (size_t i = 0; i < ARRAY_SIZE(entries_); i++) {
-    entries_[i].code = Code::ReadOnlyHandle();
-    *(entries_[i].code) =
-        Generate(entries_[i].name, &object_pool_builder, entries_[i].generator);
+  static void (compiler::StubCodeCompiler::* const generators[])() = {
+#define STUB_CODE_DECLARE(name)                                                \
+  &compiler::StubCodeCompiler::Generate##name##Stub,
+      VM_STUB_CODE_LIST(STUB_CODE_DECLARE)
+#undef STUB_CODE_DECLARE
+  };
+
+  for (intptr_t i = 0; i < kNumStubEntries; i++) {
+    handles_[i] = Code::ReadOnlyHandle();
+    *(handles_[i]) =
+        Generate(StubNames[i], &object_pool_builder, generators[i]);
   }
 
   const ObjectPool& object_pool =
       ObjectPool::Handle(ObjectPool::NewFromBuilder(object_pool_builder));
 
-  for (size_t i = 0; i < ARRAY_SIZE(entries_); i++) {
-    entries_[i].code->set_object_pool(object_pool.ptr());
+  for (intptr_t i = 0; i < kNumStubEntries; i++) {
+    handles_[i]->set_object_pool(object_pool.ptr());
   }
 
   InitializationDone();
@@ -131,8 +129,8 @@ CodePtr StubCode::Generate(const char* name,
 void StubCode::Cleanup() {
   initialized_.store(false, std::memory_order_release);
 
-  for (size_t i = 0; i < ARRAY_SIZE(entries_); i++) {
-    entries_[i].code = nullptr;
+  for (intptr_t i = 0; i < kNumStubEntries; i++) {
+    handles_[i] = nullptr;
   }
 }
 
@@ -349,9 +347,9 @@ const Code& StubCode::UnoptimizedStaticCallEntry(intptr_t num_args_tested) {
 
 void StubCode::ForEachStub(
     const std::function<bool(const char*, uword)>& callback) {
-  for (size_t i = 0; i < ARRAY_SIZE(entries_); i++) {
-    if (entries_[i].code != nullptr && !entries_[i].code->IsNull()) {
-      if (!callback(entries_[i].name, entries_[i].code->EntryPoint())) {
+  for (intptr_t i = 0; i < kNumStubEntries; i++) {
+    if (handles_[i] != nullptr && !handles_[i]->IsNull()) {
+      if (!callback(StubNames[i], handles_[i]->EntryPoint())) {
         return;
       }
     }
diff --git a/runtime/vm/stub_code.h b/runtime/vm/stub_code.h
index d24989974e3..615dfe47d26 100644
--- a/runtime/vm/stub_code.h
+++ b/runtime/vm/stub_code.h
@@ -69,7 +69,7 @@ class StubCode : public AllStatic {
 
 // Define the shared stub code accessors.
 #define STUB_CODE_ACCESSOR(name)                                               \
-  static const Code& name() { return *entries_[k##name##Index].code; }         \
+  static const Code& name() { return *handles_[k##name##Index]; }              \
   static intptr_t name##Size() { return name().Size(); }
   VM_STUB_CODE_LIST(STUB_CODE_ACCESSOR);
 #undef STUB_CODE_ACCESSOR
@@ -108,13 +108,13 @@ class StubCode : public AllStatic {
 
   static const Code& UnoptimizedStaticCallEntry(intptr_t num_args_tested);
 
-  static const char* NameAt(intptr_t index) { return entries_[index].name; }
+  static const char* NameAt(intptr_t index) { return StubNames[index]; }
 
-  static const Code& EntryAt(intptr_t index) { return *(entries_[index].code); }
+  static const Code& EntryAt(intptr_t index) { return *(handles_[index]); }
   static void EntryAtPut(intptr_t index, Code* entry) {
     DEBUG_ASSERT(entry->IsReadOnlyHandle());
-    ASSERT(entries_[index].code == nullptr);
-    entries_[index].code = entry;
+    ASSERT(handles_[index] == nullptr);
+    handles_[index] = entry;
   }
   static intptr_t NumEntries() { return kNumStubEntries; }
 
@@ -140,14 +140,7 @@ class StubCode : public AllStatic {
         kNumStubEntries
   };
 
-  struct StubCodeEntry {
-    Code* code;
-    const char* name;
-#if !defined(DART_PRECOMPILED_RUNTIME)
-    void (compiler::StubCodeCompiler::*generator)();
-#endif
-  };
-  static StubCodeEntry entries_[kNumStubEntries];
+  static Code* handles_[kNumStubEntries];
   static AcqRelAtomic<bool> initialized_;
 };