Reland "Don't use shared hotness counters for debuggable runtimes""

This reverts commit 834fb38bc0fb16d7d79bc877fced920065bbff82.

Reason for revert: Reland after a fix for the failing test landed b/299090869

Bug: 296416302
Change-Id: Iddbde561e292d8d9177538a5d2ff162355041d9a

2 files changed, 13 insertions, 5 deletions

diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index 1edb694a1d..953cc676dc 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -2236,11 +2236,14 @@ bool ClassLinker::AddImageSpace(gc::space::ImageSpace* space,
     // If we are profiling the boot classpath, we disable the shared memory
     // optimization to make sure boot classpath methods all get properly
     // profiled.
+    // For debuggable runtimes we don't use AOT code, so don't use shared memory
+    // optimization so the methods can be JITed better.
     //
     // We need to disable the flag before doing ResetCounter below, as counters
     // of shared memory method always hold the "hot" value.
     if (!runtime->IsZygote() ||
-        runtime->GetJITOptions()->GetProfileSaverOptions().GetProfileBootClassPath()) {
+        runtime->GetJITOptions()->GetProfileSaverOptions().GetProfileBootClassPath() ||
+        runtime->IsJavaDebuggable()) {
       header.VisitPackedArtMethods([&](ArtMethod& method) REQUIRES_SHARED(Locks::mutator_lock_) {
         method.ClearMemorySharedMethod();
       }, space->Begin(), image_pointer_size_);
diff --git a/runtime/runtime.cc b/runtime/runtime.cc
index 8e70de5445..c234c6491d 100644
--- a/runtime/runtime.cc
+++ b/runtime/runtime.cc
@@ -3277,10 +3277,12 @@ RuntimeCallbacks* Runtime::GetRuntimeCallbacks() {
   return callbacks_.get();
 }
 
-// Used to patch boot image method entry point to interpreter bridge.
-class UpdateEntryPointsClassVisitor : public ClassVisitor {
+// Used to update boot image to not use AOT code. This is used when transitioning the runtime to
+// java debuggable. This visitor re-initializes the entry points without using AOT code. This also
+// disables shared hotness counters so the necessary methods can be JITed more efficiently.
+class DeoptimizeBootImageClassVisitor : public ClassVisitor {
  public:
-  explicit UpdateEntryPointsClassVisitor(instrumentation::Instrumentation* instrumentation)
+  explicit DeoptimizeBootImageClassVisitor(instrumentation::Instrumentation* instrumentation)
       : instrumentation_(instrumentation) {}
 
   bool operator()(ObjPtr<mirror::Class> klass) override REQUIRES(Locks::mutator_lock_) {
@@ -3314,6 +3316,9 @@ class UpdateEntryPointsClassVisitor : public ClassVisitor {
         m.ClearPreCompiled();
         instrumentation_->InitializeMethodsCode(&m, /*aot_code=*/ nullptr);
       }
+
+      // Clear MemorySharedAccessFlags so the boot class methods can be JITed better.
+      m.ClearMemorySharedMethod();
     }
     return true;
   }
@@ -3334,7 +3339,7 @@ void Runtime::DeoptimizeBootImage() {
   // If we've already started and we are setting this runtime to debuggable,
   // we patch entry points of methods in boot image to interpreter bridge, as
   // boot image code may be AOT compiled as not debuggable.
-  UpdateEntryPointsClassVisitor visitor(GetInstrumentation());
+  DeoptimizeBootImageClassVisitor visitor(GetInstrumentation());
   GetClassLinker()->VisitClasses(&visitor);
   jit::Jit* jit = GetJit();
   if (jit != nullptr) {