Changeset 286033 in webkit

Timestamp:

Nov 18, 2021, 3:09:07 PM (5 years ago)

Author:

mark.lam@apple.com

Message:

CellAttributes should be returned by value.
​https://bugs.webkit.org/show_bug.cgi?id=233335
rdar://85568435

Reviewed by Yusuke Suzuki.

CellAttributes fits in 16 bits, and client code never modifies returned CellAttributes
values. Hence, there is no reason to return them by reference.

Also fixed a bit-rotted comment in SubSpace.h.

• heap/BlockDirectory.h:

(JSC::BlockDirectory::attributes const):

• heap/HeapCellType.h:

(JSC::HeapCellType::attributes const):

• heap/MarkedBlock.h:

(JSC::MarkedBlock::Handle::attributes const):
(JSC::MarkedBlock::attributes const):

• heap/PreciseAllocation.h:

(JSC::PreciseAllocation::attributes const):

• heap/Subspace.h:
• heap/SubspaceInlines.h:

(JSC::Subspace::attributes const):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• heap/BlockDirectory.h (modified) (2 diffs)
• heap/HeapCellType.h (modified) (2 diffs)
• heap/MarkedBlock.h (modified) (3 diffs)
• heap/PreciseAllocation.h (modified) (1 diff)
• heap/Subspace.h (modified) (2 diffs)
• heap/SubspaceInlines.h (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2021-11-18  Mark Lam  <mark.lam@apple.com>
+
+        CellAttributes should be returned by value.
+        https://bugs.webkit.org/show_bug.cgi?id=233335
+        rdar://85568435
+
+        Reviewed by Yusuke Suzuki.
+
+        CellAttributes fits in 16 bits, and client code never modifies returned CellAttributes
+        values.  Hence, there is no reason to return them by reference.
+
+        Also fixed a bit-rotted comment in SubSpace.h.
+
+        * heap/BlockDirectory.h:
+        (JSC::BlockDirectory::attributes const):
+        * heap/HeapCellType.h:
+        (JSC::HeapCellType::attributes const):
+        * heap/MarkedBlock.h:
+        (JSC::MarkedBlock::Handle::attributes const):
+        (JSC::MarkedBlock::attributes const):
+        * heap/PreciseAllocation.h:
+        (JSC::PreciseAllocation::attributes const):
+        * heap/Subspace.h:
+        * heap/SubspaceInlines.h:
+        (JSC::Subspace::attributes const):
+
 2021-11-18  Robin Morisset  <rmorisset@apple.com>
 

trunk/Source/JavaScriptCore/heap/BlockDirectory.h

@@ -1 +1 @@
 /*
- * Copyright (C) 2012-2018 Apple Inc. All rights reserved.
+ * Copyright (C) 2012-2021 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -75 +75 @@
     void assertNoUnswept();
     size_t cellSize() const { return m_cellSize; }
-    const CellAttributes& attributes() const { return m_attributes; }
+    const CellAttributes attributes() const { return m_attributes; }
     bool needsDestruction() const { return m_attributes.destruction == NeedsDestruction; }
     DestructionMode destruction() const { return m_attributes.destruction; }

trunk/Source/JavaScriptCore/heap/HeapCellType.h

@@ -1 +1 @@
 /*
- * Copyright (C) 2017 Apple Inc. All rights reserved.
+ * Copyright (C) 2017-2021 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -37 +37 @@
     JS_EXPORT_PRIVATE virtual ~HeapCellType();
 
-    const CellAttributes& attributes() const { return m_attributes; }
+    const CellAttributes attributes() const { return m_attributes; }
 
     // The purpose of overriding this is to specialize the sweep for your destructors. This won't

trunk/Source/JavaScriptCore/heap/MarkedBlock.h

@@ -162 +162 @@
         inline unsigned cellsPerBlock();
         
-        const CellAttributes& attributes() const;
+        const CellAttributes attributes() const;
         DestructionMode destruction() const;
         bool needsDestruction() const;
@@ -348 +348 @@
         
     size_t cellSize();
-    const CellAttributes& attributes() const;
+    const CellAttributes attributes() const;
     
     bool hasAnyMarked() const;
@@ -512 +512 @@
 }
 
-inline const CellAttributes& MarkedBlock::Handle::attributes() const
+inline const CellAttributes MarkedBlock::Handle::attributes() const
 {
     return m_attributes;
 }
 
-inline const CellAttributes& MarkedBlock::attributes() const
+inline const CellAttributes MarkedBlock::attributes() const
 {
     return handle().attributes();

trunk/Source/JavaScriptCore/heap/PreciseAllocation.h

@@ -122 +122 @@
     }
     
-    const CellAttributes& attributes() const { return m_attributes; }
+    const CellAttributes attributes() const { return m_attributes; }
     
     Dependency aboutToMark(HeapVersion) { return Dependency(); }

trunk/Source/JavaScriptCore/heap/Subspace.h

@@ -40 +40 @@
 // The idea of subspaces is that you can provide some custom behavior for your objects if you
 // allocate them from a custom Subspace in which you override some of the virtual methods. This
-// class is the baseclass of Subspaces. Usually you will use either Subspace or FixedSizeSubspace.
+// class is the baseclass of all subspaces e.g. CompleteSubspace, IsoSubspace.
 class Subspace {
     WTF_MAKE_NONCOPYABLE(Subspace);
@@ -51 +51 @@
     MarkedSpace& space() const { return m_space; }
     
-    const CellAttributes& attributes() const;
+    const CellAttributes attributes() const;
     HeapCellType* heapCellType() const { return m_heapCellType; }
     AlignedMemoryAllocator* alignedMemoryAllocator() const { return m_alignedMemoryAllocator; }

trunk/Source/JavaScriptCore/heap/SubspaceInlines.h

@@ -153 +153 @@
 }
 
-inline const CellAttributes& Subspace::attributes() const
+inline const CellAttributes Subspace::attributes() const
 {
     return m_heapCellType->attributes();