[baseline] Remove UndoLastAllocationAt

It seems like SP on heap does not produce too much memory fragmentation,
therefore we do not need UndoLastAllocationAt.

Bug: v8:11872
Change-Id: Id2e44405329b52c1dcd6cd81bfc72ffba00035ee
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3129428
Auto-Submit: Victor Gomes <victorgomes@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76581}

src/heap/factory.cc

@@ -313,7 +313,8 @@ void Factory::CodeBuilder::FinalizeOnHeapCode(Handle<Code> code,
       Code::SizeFor(code_desc_.instruction_size() + code_desc_.metadata_size());
   int size_to_trim = old_object_size - new_object_size;
   DCHECK_GE(size_to_trim, 0);
-  heap->UndoLastAllocationAt(code->address() + new_object_size, size_to_trim);
+  heap->CreateFillerObjectAt(code->address() + new_object_size, size_to_trim,
+                             ClearRecordedSlots::kNo);
 }
 
 MaybeHandle<Code> Factory::NewEmptyCode(CodeKind kind, int buffer_size) {

src/heap/heap.cc

@@ -3469,15 +3469,6 @@ void Heap::RightTrimWeakFixedArray(WeakFixedArray object,
                                        elements_to_trim * kTaggedSize);
 }
 
-void Heap::UndoLastAllocationAt(Address addr, int size) {
-  DCHECK_LE(0, size);
-  if (size == 0) return;
-  if (code_space_->TryFreeLast(addr, size)) {
-    return;
-  }
-  CreateFillerObjectAt(addr, size, ClearRecordedSlots::kNo);
-}
-
 template <typename T>
 void Heap::CreateFillerForArray(T object, int elements_to_trim,
                                 int bytes_to_trim) {

src/heap/heap.h

@@ -579,8 +579,6 @@ class Heap {
                                              int elements_to_trim);
   void RightTrimWeakFixedArray(WeakFixedArray obj, int elements_to_trim);
 
-  void UndoLastAllocationAt(Address addr, int size);
-
   // Converts the given boolean condition to JavaScript boolean value.
   inline Oddball ToBoolean(bool condition);