[heap] Simplify zapping of old optimized code maps.

src/objects.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/objects.h"
 
 #include <cmath>
 #include <iomanip>
 #include <sstream>
 
@@ skipping 11066 matching lines @@
       return;
     }
 
     // Copy old optimized code map and append one new entry.
     new_code_map = isolate->factory()->CopyFixedArrayAndGrow(
         old_code_map, kEntryLength, TENURED);
     // TODO(mstarzinger): Temporary workaround. The allocation above might have
     // flushed the optimized code map and the copy we created is full of holes.
     // For now we just give up on adding the entry and pretend it got flushed.
     if (shared->optimized_code_map()->IsSmi()) return;
-    int old_length = old_code_map->length();
-    // Zap the old map to avoid any stale entries. Note that this is required
-    // for correctness because entries are being treated weakly by the GC.
-    MemsetPointer(old_code_map->data_start(), isolate->heap()->the_hole_value(),
-                  old_length);
-    entry = old_length;
+    entry = old_code_map->length();
   }
   new_code_map->set(entry + kContextOffset, *native_context);
   new_code_map->set(entry + kCachedCodeOffset, *code);
   new_code_map->set(entry + kLiteralsOffset, *literals);
   new_code_map->set(entry + kOsrAstIdOffset, Smi::FromInt(osr_ast_id.ToInt()));
 
 #ifdef DEBUG
   for (int i = kEntriesStart; i < new_code_map->length(); i += kEntryLength) {
     DCHECK(new_code_map->get(i + kContextOffset)->IsNativeContext());
     Object* code = new_code_map->get(i + kCachedCodeOffset);
     if (code != isolate->heap()->undefined_value()) {
       DCHECK(code->IsCode());
       DCHECK(Code::cast(code)->kind() == Code::OPTIMIZED_FUNCTION);
     }
     DCHECK(new_code_map->get(i + kLiteralsOffset)->IsFixedArray());
     DCHECK(new_code_map->get(i + kOsrAstIdOffset)->IsSmi());
   }
 #endif
 
-  if (Heap::ShouldZapGarbage()) {
-    // Zap any old optimized code map for heap-verifier.
-    if (!shared->optimized_code_map()->IsSmi()) {
-      FixedArray* old_code_map = FixedArray::cast(shared->optimized_code_map());
-      old_code_map->FillWithHoles(0, old_code_map->length());
-    }
+  // Zap any old optimized code map.
+  if (!shared->optimized_code_map()->IsSmi()) {
+    FixedArray* old_code_map = FixedArray::cast(shared->optimized_code_map());
+    old_code_map->FillWithHoles(0, old_code_map->length());
   }
 
   shared->set_optimized_code_map(*new_code_map);
 }
 
 
 void SharedFunctionInfo::ClearOptimizedCodeMap() {
-  if (Heap::ShouldZapGarbage()) {
-    // Zap any old optimized code map for heap-verifier.
-    if (!optimized_code_map()->IsSmi()) {
-      FixedArray* old_code_map = FixedArray::cast(optimized_code_map());
-      old_code_map->FillWithHoles(0, old_code_map->length());
-    }
+  // Zap any old optimized code map.
+  if (!optimized_code_map()->IsSmi()) {
+    FixedArray* old_code_map = FixedArray::cast(optimized_code_map());
+    old_code_map->FillWithHoles(0, old_code_map->length());
   }
 
   set_optimized_code_map(Smi::FromInt(0));
 }
 
 
 void SharedFunctionInfo::EvictFromOptimizedCodeMap(Code* optimized_code,
                                                    const char* reason) {
   DisallowHeapAllocation no_gc;
   if (optimized_code_map()->IsSmi()) return;
@@ skipping 6752 matching lines @@
   if (cell->value() != *new_value) {
     cell->set_value(*new_value);
     Isolate* isolate = cell->GetIsolate();
     cell->dependent_code()->DeoptimizeDependentCodeGroup(
         isolate, DependentCode::kPropertyCellChangedGroup);
   }
 }
 
 }  // namespace internal
 }  // namespace v8