Changeset 162277 in webkit

Timestamp:

Jan 18, 2014 3:09:48 PM (10 years ago)

Author:

akling@apple.com

Message:

CodeBlock: Size m_exceptionHandlers to fit from creation.
<​https://webkit.org/b/127234>

Avoid allocation churn for CodeBlock::m_exceptionHandlers.

Reviewed by Anders Carlsson.

• bytecode/CodeBlock.h:

Removed unused CodeBlock::allocateHandlers() function.

• bytecode/CodeBlock.cpp:

(JSC::CodeBlock::CodeBlock):

Use resizeToFit() instead of grow() for m_exceptionHandlers
since we know it's never going to change size.

(JSC::CodeBlock::shrinkToFit):

No need to shrink m_exceptionHandlers here since it's already
the perfect size.

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• bytecode/CodeBlock.cpp (modified) (2 diffs)
• bytecode/CodeBlock.h (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2014-01-18  Andreas Kling  <akling@apple.com>
+
+        CodeBlock: Size m_exceptionHandlers to fit from creation.
+        <https://webkit.org/b/127234>
+
+        Avoid allocation churn for CodeBlock::m_exceptionHandlers.
+
+        Reviewed by Anders Carlsson.
+
+        * bytecode/CodeBlock.h:
+
+            Removed unused CodeBlock::allocateHandlers() function.
+
+        * bytecode/CodeBlock.cpp:
+        (JSC::CodeBlock::CodeBlock):
+
+            Use resizeToFit() instead of grow() for m_exceptionHandlers
+            since we know it's never going to change size.
+
+        (JSC::CodeBlock::shrinkToFit):
+
+            No need to shrink m_exceptionHandlers here since it's already
+            the perfect size.
+
 2014-01-18  Mark Lam  <mark.lam@apple.com>
 

trunk/Source/JavaScriptCore/bytecode/CodeBlock.cpp

@@ -1602 +1602 @@
         }
         if (size_t count = unlinkedCodeBlock->numberOfExceptionHandlers()) {
-            m_rareData->m_exceptionHandlers.grow(count);
+            m_rareData->m_exceptionHandlers.resizeToFit(count);
             size_t nonLocalScopeDepth = scope->depth();
             for (size_t i = 0; i < count; i++) {
@@ -2602 +2602 @@
         }
     } // else don't shrink these, because we would have already pointed pointers into these tables.
-
-    if (m_rareData)
-        m_rareData->m_exceptionHandlers.shrinkToFit();
 }
 

trunk/Source/JavaScriptCore/bytecode/CodeBlock.h

@@ -546 +546 @@
 
     size_t numberOfExceptionHandlers() const { return m_rareData ? m_rareData->m_exceptionHandlers.size() : 0; }
-    void allocateHandlers(const Vector<UnlinkedHandlerInfo>& unlinkedHandlers)
-    {
-        size_t count = unlinkedHandlers.size();
-        if (!count)
-            return;
-        createRareDataIfNecessary();
-        m_rareData->m_exceptionHandlers.resize(count);
-        for (size_t i = 0; i < count; ++i) {
-            m_rareData->m_exceptionHandlers[i].start = unlinkedHandlers[i].start;
-            m_rareData->m_exceptionHandlers[i].end = unlinkedHandlers[i].end;
-            m_rareData->m_exceptionHandlers[i].target = unlinkedHandlers[i].target;
-            m_rareData->m_exceptionHandlers[i].scopeDepth = unlinkedHandlers[i].scopeDepth;
-        }
-
-    }
     HandlerInfo& exceptionHandler(int index) { RELEASE_ASSERT(m_rareData); return m_rareData->m_exceptionHandlers[index]; }