[cleanup] Rename DeoptimizeBaseline to DiscardBaselineCode

- Baseline is to be consider non-optimized code, so for consistency we rename these functions to DiscardBaselineCode.
- Move to debug/, since discarding baseline code is only used by the debugger.
- %DeoptimizeNow and %DeoptimizeFunction are not to be used to tier down from Sparkplug to Ignition

Change-Id: I050607d4d6978907c589e54c57e940979b0a9a15
Bug: v8:11429
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2692699
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Victor Gomes <victorgomes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72732}

src/debug/debug.cc

@@ -1241,13 +1241,80 @@ void Debug::ClearOneShot() {
   }
 }
 
+namespace {
+class DiscardBaselineCodeVisitor : public ThreadVisitor {
+ public:
+  explicit DiscardBaselineCodeVisitor(SharedFunctionInfo shared)
+      : shared_(shared) {}
+  DiscardBaselineCodeVisitor() : shared_(SharedFunctionInfo()) {}
+
+  void VisitThread(Isolate* isolate, ThreadLocalTop* top) override {
+    bool deopt_all = shared_ == SharedFunctionInfo();
+    for (JavaScriptFrameIterator it(isolate, top); !it.done(); it.Advance()) {
+      if (it.frame()->type() == StackFrame::BASELINE) {
+        BaselineFrame* frame = BaselineFrame::cast(it.frame());
+        if (!deopt_all && frame->function().shared() != shared_) continue;
+        frame->InterpretedFrame::PatchBytecodeOffset(
+            frame->GetBytecodeOffset());
+        Address* pc_addr = frame->pc_address();
+        Address advance = BUILTIN_CODE(isolate, InterpreterEnterBytecodeAdvance)
+                              ->InstructionStart();
+        PointerAuthentication::ReplacePC(pc_addr, advance, kSystemPointerSize);
+      }
+    }
+  }
+
+ private:
+  SharedFunctionInfo shared_;
+  DISALLOW_GARBAGE_COLLECTION(no_gc_)
+};
+}  // namespace
+
+void Debug::DiscardBaselineCode(SharedFunctionInfo shared) {
+  DCHECK_EQ(shared.GetCode().kind(), CodeKind::BASELINE);
+  Isolate* isolate = shared.GetIsolate();
+  DiscardBaselineCodeVisitor visitor(shared);
+  visitor.VisitThread(isolate, isolate->thread_local_top());
+  isolate->thread_manager()->IterateArchivedThreads(&visitor);
+  // TODO(v8:11429): Avoid this heap walk somehow.
+  HeapObjectIterator iterator(isolate->heap());
+  auto trampoline = BUILTIN_CODE(isolate, InterpreterEntryTrampoline);
+  shared.flush_baseline_data();
+  for (HeapObject obj = iterator.Next(); !obj.is_null();
+       obj = iterator.Next()) {
+    if (obj.IsJSFunction()) {
+      JSFunction fun = JSFunction::cast(obj);
+      if (fun.shared() == shared && fun.code().kind() == CodeKind::BASELINE) {
+        fun.set_code(*trampoline);
+      }
+    }
+  }
+}
+
+void Debug::DiscardAllBaselineCode() {
+  DiscardBaselineCodeVisitor visitor;
+  visitor.VisitThread(isolate_, isolate_->thread_local_top());
+  HeapObjectIterator iterator(isolate_->heap());
+  auto trampoline = BUILTIN_CODE(isolate_, InterpreterEntryTrampoline);
+  isolate_->thread_manager()->IterateArchivedThreads(&visitor);
+  for (HeapObject obj = iterator.Next(); !obj.is_null();
+       obj = iterator.Next()) {
+    if (obj.IsJSFunction()) {
+      JSFunction fun = JSFunction::cast(obj);
+      if (fun.shared().HasBaselineData()) {
+        fun.set_code(*trampoline);
+      }
+    }
+  }
+}
+
 void Debug::DeoptimizeFunction(Handle<SharedFunctionInfo> shared) {
   // Deoptimize all code compiled from this shared function info including
   // inlining.
   isolate_->AbortConcurrentOptimization(BlockingBehavior::kBlock);
 
-  if (shared->GetCode().kind() == CodeKind::BASELINE) {
-    Deoptimizer::DeoptimizeBaseline(*shared);
+  if (shared->HasBaselineData()) {
+    DiscardBaselineCode(*shared);
   }
 
   bool found_something = false;
@@ -1284,6 +1351,7 @@ void Debug::PrepareFunctionForDebugExecution(
   if (debug_info->CanBreakAtEntry()) {
     // Deopt everything in case the function is inlined anywhere.
     Deoptimizer::DeoptimizeAll(isolate_);
+    DiscardAllBaselineCode();
     InstallDebugBreakTrampoline();
   } else {
     DeoptimizeFunction(shared);

src/debug/debug.h

@@ -265,6 +265,9 @@ class V8_EXPORT_PRIVATE Debug {
   void SetBreakOnNextFunctionCall();
   void ClearBreakOnNextFunctionCall();
 
+  void DiscardBaselineCode(SharedFunctionInfo shared);
+  void DiscardAllBaselineCode();
+
   void DeoptimizeFunction(Handle<SharedFunctionInfo> shared);
   void PrepareFunctionForDebugExecution(Handle<SharedFunctionInfo> shared);
   void InstallDebugBreakTrampoline();

src/deoptimizer/deoptimizer.cc

@@ -382,7 +382,6 @@ void Deoptimizer::DeoptimizeAll(Isolate* isolate) {
   TraceDeoptAll(isolate);
   isolate->AbortConcurrentOptimization(BlockingBehavior::kBlock);
   DisallowGarbageCollection no_gc;
-  DeoptimizeAllBaseline(isolate);
   // For all contexts, mark all code, then deoptimize.
   Object context = isolate->heap()->native_contexts_list();
   while (!context.IsUndefined(isolate)) {
@@ -421,73 +420,6 @@ void Deoptimizer::MarkAllCodeForContext(NativeContext native_context) {
   }
 }
 
-namespace {
-class DeoptimizeBaselineVisitor : public ThreadVisitor {
- public:
-  explicit DeoptimizeBaselineVisitor(SharedFunctionInfo shared)
-      : shared_(shared) {}
-  DeoptimizeBaselineVisitor() : shared_(SharedFunctionInfo()) {}
-
-  void VisitThread(Isolate* isolate, ThreadLocalTop* top) override {
-    bool deopt_all = shared_ == SharedFunctionInfo();
-    for (JavaScriptFrameIterator it(isolate, top); !it.done(); it.Advance()) {
-      if (it.frame()->type() == StackFrame::BASELINE) {
-        BaselineFrame* frame = BaselineFrame::cast(it.frame());
-        if (!deopt_all && frame->function().shared() != shared_) continue;
-        frame->InterpretedFrame::PatchBytecodeOffset(
-            frame->GetBytecodeOffset());
-        Address* pc_addr = frame->pc_address();
-        Address advance = BUILTIN_CODE(isolate, InterpreterEnterBytecodeAdvance)
-                              ->InstructionStart();
-        PointerAuthentication::ReplacePC(pc_addr, advance, kSystemPointerSize);
-      }
-    }
-  }
-
- private:
-  SharedFunctionInfo shared_;
-  DISALLOW_GARBAGE_COLLECTION(no_gc_)
-};
-}  // namespace
-
-void Deoptimizer::DeoptimizeBaseline(SharedFunctionInfo shared) {
-  DCHECK_EQ(shared.GetCode().kind(), CodeKind::BASELINE);
-  Isolate* isolate = shared.GetIsolate();
-  DeoptimizeBaselineVisitor visitor(shared);
-  visitor.VisitThread(isolate, isolate->thread_local_top());
-  isolate->thread_manager()->IterateArchivedThreads(&visitor);
-  // TODO(v8:11429): Avoid this heap walk somehow.
-  HeapObjectIterator iterator(isolate->heap());
-  auto trampoline = BUILTIN_CODE(isolate, InterpreterEntryTrampoline);
-  shared.flush_baseline_data();
-  for (HeapObject obj = iterator.Next(); !obj.is_null();
-       obj = iterator.Next()) {
-    if (obj.IsJSFunction()) {
-      JSFunction fun = JSFunction::cast(obj);
-      if (fun.shared() == shared && fun.code().kind() == CodeKind::BASELINE) {
-        fun.set_code(*trampoline);
-      }
-    }
-  }
-}
-
-void Deoptimizer::DeoptimizeAllBaseline(Isolate* isolate) {
-  DeoptimizeBaselineVisitor visitor;
-  visitor.VisitThread(isolate, isolate->thread_local_top());
-  HeapObjectIterator iterator(isolate->heap());
-  auto trampoline = BUILTIN_CODE(isolate, InterpreterEntryTrampoline);
-  isolate->thread_manager()->IterateArchivedThreads(&visitor);
-  for (HeapObject obj = iterator.Next(); !obj.is_null();
-       obj = iterator.Next()) {
-    if (obj.IsJSFunction()) {
-      JSFunction fun = JSFunction::cast(obj);
-      if (fun.shared().HasBaselineData()) {
-        fun.set_code(*trampoline);
-      }
-    }
-  }
-}
-
 void Deoptimizer::DeoptimizeFunction(JSFunction function, Code code) {
   Isolate* isolate = function.GetIsolate();
   RuntimeCallTimerScope runtimeTimer(isolate,

src/deoptimizer/deoptimizer.h

@@ -66,12 +66,6 @@ class Deoptimizer : public Malloced {
   // instead of the function code (e.g. OSR code not installed on function).
   static void DeoptimizeFunction(JSFunction function, Code code = Code());
 
-  // From Baseline to Ignition.
-  // TODO(v8:11429): Consider moving this to the debugger, since it's only for
-  // debug.
-  static void DeoptimizeBaseline(SharedFunctionInfo shared);
-  static void DeoptimizeAllBaseline(Isolate* isolate);
-
   // Deoptimize all code in the given isolate.
   V8_EXPORT_PRIVATE static void DeoptimizeAll(Isolate* isolate);
 

src/runtime/runtime-test.cc

@@ -190,10 +190,6 @@ RUNTIME_FUNCTION(Runtime_DeoptimizeFunction) {
 
   if (function->HasAttachedOptimizedCode()) {
     Deoptimizer::DeoptimizeFunction(*function);
-  } else if (function->code().kind() == CodeKind::BASELINE) {
-    // TODO(v8:11429): This should either be in Deoptimizer::DeoptimizeFunction,
-    // or not be considered deoptimization at all.
-    Deoptimizer::DeoptimizeBaseline(function->shared());
   }
 
   return ReadOnlyRoots(isolate).undefined_value();
@@ -212,8 +208,6 @@ RUNTIME_FUNCTION(Runtime_DeoptimizeNow) {
 
   if (function->HasAttachedOptimizedCode()) {
     Deoptimizer::DeoptimizeFunction(*function);
-  } else if (function->code().kind() == CodeKind::BASELINE) {
-    Deoptimizer::DeoptimizeBaseline(function->shared());
   }
 
   return ReadOnlyRoots(isolate).undefined_value();

test/mjsunit/baseline/test-baseline.js

@@ -310,26 +310,3 @@ assertEquals(run((x)=>{
   assertTrue(isBaseline(f1));
   assertTrue(isBaseline(f2));
 })();
-
-// DeoptNow to Ignition
-(function() {
-  function f() { %DeoptimizeNow(); }
-  f();
-  assertTrue(isInterpreted(f));
-  %CompileBaseline(f);
-  f();
-  assertTrue(isInterpreted(f));
-})();
-
-// Deopt to Ignition
-(function() {
-  function f() {}
-  f();
-  assertTrue(isInterpreted(f));
-  %CompileBaseline(f);
-  f();
-  assertTrue(isBaseline(f));
-  %DeoptimizeFunction(f);
-  f();
-  assertTrue(isInterpreted(f));
-})();