[runtime-profiler] Cleanup MarkCandidatesForOptimization* functions

MarkCandidatesForOptimizationFromBytecode/
MarkCandidatesForOptimizationFromCode are called when bytecode budget
interrupt occurs from interpreted / optimized code. The logic in these
two functions is very similar. This cl merges this logic into one
function.

This cl also removes FLAG_frame_count which specifies the
number of frames we need to look at for tiering up on a bytecode
budget interrupt. The default value is set to 1 and in its current
form it isn't very useful.

Bug: v8:9684
Change-Id: I9f56034f2857672921673b9b68b3615765c0ccfe
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2565514
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71561}

src/execution/runtime-profiler.cc

@@ -303,49 +303,35 @@ RuntimeProfiler::MarkCandidatesForOptimizationScope::
   profiler_->any_ic_changed_ = false;
 }
 
-void RuntimeProfiler::MarkCandidatesForOptimizationFromBytecode() {
+void RuntimeProfiler::MarkCandidatesForOptimization(JavaScriptFrame* frame) {
   if (!isolate_->use_optimizer()) return;
   MarkCandidatesForOptimizationScope scope(this);
-  int i = 0;
-  for (JavaScriptFrameIterator it(isolate_); i < FLAG_frame_count && !it.done();
-       i++, it.Advance()) {
-    JavaScriptFrame* frame = it.frame();
-    if (!frame->is_interpreted()) continue;
 
-    JSFunction function = frame->function();
-    DCHECK(function.shared().is_compiled());
-    if (!function.shared().IsInterpreted()) continue;
+  JSFunction function = frame->function();
+  CodeKind code_kind = frame->is_interpreted() ? CodeKind::INTERPRETED_FUNCTION
+                                               : function.code().kind();
 
-    if (!function.has_feedback_vector()) continue;
+  DCHECK(function.shared().is_compiled());
+  DCHECK(function.shared().IsInterpreted());
 
-    function.feedback_vector().SaturatingIncrementProfilerTicks();
+  DCHECK_IMPLIES(CodeKindIsOptimizedJSFunction(code_kind),
+                 function.has_feedback_vector());
+  if (!function.has_feedback_vector()) return;
 
-    MaybeOptimizeFrame(function, frame, CodeKind::INTERPRETED_FUNCTION);
-  }
+  function.feedback_vector().SaturatingIncrementProfilerTicks();
+  MaybeOptimizeFrame(function, frame, code_kind);
 }
 
-void RuntimeProfiler::MarkCandidatesForOptimizationFromCode() {
-  if (!isolate_->use_optimizer()) return;
-  MarkCandidatesForOptimizationScope scope(this);
-  int i = 0;
-  for (JavaScriptFrameIterator it(isolate_); i < FLAG_frame_count && !it.done();
-       i++, it.Advance()) {
-    JavaScriptFrame* frame = it.frame();
-    if (!frame->is_optimized()) continue;
-
-    JSFunction function = frame->function();
-    auto code_kind = function.code().kind();
-    if (!CodeKindIsOptimizedAndCanTierUp(code_kind)) {
-      continue;
-    }
-
-    DCHECK(function.shared().is_compiled());
-    DCHECK(function.has_feedback_vector());
-
-    function.feedback_vector().SaturatingIncrementProfilerTicks();
+void RuntimeProfiler::MarkCandidatesForOptimizationFromBytecode() {
+  JavaScriptFrameIterator it(isolate_);
+  DCHECK(it.frame()->is_interpreted());
+  MarkCandidatesForOptimization(it.frame());
+}
 
-    MaybeOptimizeFrame(function, frame, code_kind);
-  }
+void RuntimeProfiler::MarkCandidatesForOptimizationFromCode() {
+  JavaScriptFrameIterator it(isolate_);
+  DCHECK(it.frame()->is_optimized());
+  MarkCandidatesForOptimization(it.frame());
 }
 
 }  // namespace internal

src/execution/runtime-profiler.h

@@ -35,6 +35,9 @@ class RuntimeProfiler {
                                  int nesting_levels = 1);
 
  private:
+  // Helper function called from MarkCandidatesForOptimization*
+  void MarkCandidatesForOptimization(JavaScriptFrame* frame);
+
   // Make the decision whether to optimize the given function, and mark it for
   // optimization if the decision was 'yes'.
   void MaybeOptimizeFrame(JSFunction function, JavaScriptFrame* frame,

src/flags/flag-definitions.h

@@ -912,9 +912,6 @@ DEFINE_INT(wasm_max_initial_code_space_reservation, 0,
 DEFINE_BOOL(experimental_wasm_allow_huge_modules, false,
             "allow wasm modules bigger than 1GB, but below ~2GB")
 
-// Profiler flags.
-DEFINE_INT(frame_count, 1, "number of stack frames inspected by the profiler")
-
 DEFINE_INT(stress_sampling_allocation_profiler, 0,
            "Enables sampling allocation profiler with X as a sample interval")