Changeset 39182 in webkit for trunk/JavaScriptCore/bytecode/CodeBlock.h

Timestamp:

Dec 10, 2008, 12:05:53 PM (16 years ago)

Author:

[email protected]

Message:

2008-12-10 Sam Weinig <​[email protected]>

Reviewed by Geoffrey Garen.

<rdar://problem/6428332> Remove the CTI return address table from CodeBlock

Step 2:

Convert the return address table from a HashMap to a sorted Vector. This
reduces the size of the data structure by ~4.5MB on Membuster head.

SunSpider reports a 0.5% progression.

• bytecode/CodeBlock.cpp: (JSC::sizeInBytes): Generic method to get the cost of a Vector. (JSC::CodeBlock::dumpStatistics): Add dumping of member sizes.
• bytecode/CodeBlock.h: (JSC::PC::PC): Struct representing NativePC -> VirtualPC mappings. (JSC::getNativePC): Helper for binary chop. (JSC::CodeBlock::getBytecodeIndex): Used to get the VirtualPC from a NativePC using a binary chop of the pcVector. (JSC::CodeBlock::pcVector): Accessor.

• interpreter/Interpreter.cpp: (JSC::vPCForPC): Use getBytecodeIndex instead of jitReturnAddressVPCMap().get(). (JSC::Interpreter::cti_op_instanceof): Ditto. (JSC::Interpreter::cti_op_resolve): Ditto. (JSC::Interpreter::cti_op_resolve_func): Ditto. (JSC::Interpreter::cti_op_resolve_skip): Ditto. (JSC::Interpreter::cti_op_resolve_with_base): Ditto. (JSC::Interpreter::cti_op_throw): Ditto. (JSC::Interpreter::cti_op_in): Ditto. (JSC::Interpreter::cti_vm_throw): Ditto.

• jit/JIT.cpp: (JSC::JIT::privateCompile): Reserve exact capacity and fill the pcVector.

File:

• trunk/JavaScriptCore/bytecode/CodeBlock.h (modified) (5 diffs)

trunk/JavaScriptCore/bytecode/CodeBlock.h

@@ -110 +110 @@
     };
 
+    struct PC {
+        PC(void* nativePC, unsigned bytecodeIndex)
+            : nativePC(nativePC)
+            , bytecodeIndex(bytecodeIndex)
+        {
+        }
+        
+        void* nativePC;
+        unsigned bytecodeIndex;
+    };
+
+
+    // valueAtPosition helpers for the binaryChop algorithm below.
+
     inline void* getStructureStubInfoReturnLocation(StructureStubInfo* structureStubInfo)
     {
@@ -118 +132 @@
     {
         return callLinkInfo->callReturnLocation;
+    }
+
+    inline void* getNativePC(PC* pc)
+    {
+        return pc->nativePC;
     }
 
@@ -236 +255 @@
         }
 
+        unsigned getBytecodeIndex(void* nativePC)
+        {
+            return binaryChop<PC, void*, getNativePC>(m_pcVector.begin(), m_pcVector.size(), nativePC)->bytecodeIndex;
+        }
 
         Vector<Instruction>& instructions() { return m_instructions; }
@@ -290 +313 @@
 
 #if ENABLE(JIT)
-        HashMap<void*, unsigned>& jitReturnAddressVPCMap() { return m_jitReturnAddressVPCMap; }
+        Vector<PC>& pcVector() { return m_pcVector; }
 #endif
 
@@ -391 +414 @@
 
 #if ENABLE(JIT)
-        HashMap<void*, unsigned> m_jitReturnAddressVPCMap;
+        Vector<PC> m_pcVector;
 #endif