Changeset 39156 in webkit for trunk/JavaScriptCore/bytecode/CodeBlock.cpp

Timestamp:

Dec 9, 2008, 4:26:13 PM (16 years ago)

Author:

[email protected]

Message:

2008-12-09 Sam Weinig <​[email protected]>

Reviewed by Geoffrey Garen.

Remove unnecessary extra lookup when throwing an exception.
We used to first lookup the target offset using getHandlerForVPC
and then we would lookup the native code stub using
nativeExceptionCodeForHandlerVPC. Instead, we can just pass around
the HandlerInfo.

• bytecode/CodeBlock.cpp: (JSC::CodeBlock::handlerForVPC): Return the HandlerInfo.
• bytecode/CodeBlock.h: Remove nativeExceptionCodeForHandlerVPC.

• interpreter/Interpreter.cpp: (JSC::Interpreter::throwException): Return a HandlerInfo instead of and Instruction offset. (JSC::Interpreter::privateExecute): Get the offset from HandlerInfo. (JSC::Interpreter::cti_op_throw): Get the native code from the HandleInfo. (JSC::Interpreter::cti_vm_throw): Ditto.
• interpreter/Interpreter.h:

File:

• trunk/JavaScriptCore/bytecode/CodeBlock.cpp (modified) (1 diff)

trunk/JavaScriptCore/bytecode/CodeBlock.cpp

@@ -1195 +1195 @@
 }
 
-bool CodeBlock::getHandlerForVPC(const Instruction* vPC, Instruction*& target, int& scopeDepth)
+HandlerInfo* CodeBlock::handlerForVPC(const Instruction* vPC)
 {
     if (!m_rareData)
-        return false;
-
-    Vector<HandlerInfo>::iterator ptr = m_rareData->m_exceptionHandlers.begin(); 
-    Vector<HandlerInfo>::iterator end = m_rareData->m_exceptionHandlers.end();
+        return 0;
+
     unsigned addressOffset = vPC - m_instructions.begin();
     ASSERT(addressOffset < m_instructions.size());
     
-    for (; ptr != end; ++ptr) {
+    Vector<HandlerInfo>& exceptionHandlers = m_rareData->m_exceptionHandlers;
+    for (size_t i = 0; i < exceptionHandlers.size(); ++i) {
         // Handlers are ordered innermost first, so the first handler we encounter
         // that contains the source address is the correct handler to use.
-        if (ptr->start <= addressOffset && ptr->end >= addressOffset) {
-            scopeDepth = ptr->scopeDepth;
-            target = m_instructions.begin() + ptr->target;
-            return true;
-        }
-    }
-    return false;
-}
-
-void* CodeBlock::nativeExceptionCodeForHandlerVPC(const Instruction* handlerVPC)
-{
-    if (!m_rareData)
-        return 0;
-
-    Vector<HandlerInfo>::iterator ptr = m_rareData->m_exceptionHandlers.begin(); 
-    Vector<HandlerInfo>::iterator end = m_rareData->m_exceptionHandlers.end();
-    
-    for (; ptr != end; ++ptr) {
-        Instruction*target = m_instructions.begin() + ptr->target;
-        if (handlerVPC == target)
-            return ptr->nativeCode;
+        if (exceptionHandlers[i].start <= addressOffset && exceptionHandlers[i].end >= addressOffset)
+            return &exceptionHandlers[i];
     }