Changeset 39720 in webkit for trunk/JavaScriptCore/bytecompiler/BytecodeGenerator.h

Timestamp:

Jan 8, 2009, 2:51:19 PM (16 years ago)

Author:

[email protected]

Message:

2009-01-08 Sam Weinig <​[email protected]>

Reviewed by Oliver Hunt.

Fix for ​https://bugs.webkit.org/show_bug.cgi?id=23197
Delay creating the PCVector until an exception is thrown
Part of <rdar://problem/6469060>
Don't store exception information for a CodeBlock until first exception is thrown

• Change the process for re-parsing/re-generating bytecode for exception information to use data from the original CodeBlock (offsets of GlobalResolve instructions) to aid in creating an identical instruction stream on re-parse, instead of padding interchangeable opcodes, which would result in different JITed code.
• Fix bug where the wrong ScopeChainNode was used when re-parsing/regenerating from within some odd modified scope chains.
• Lazily create the pcVector by re-JITing the regenerated CodeBlock and stealing the the pcVector from it.

Saves ~2MB on Membuster head.

• bytecode/CodeBlock.cpp: (JSC::CodeBlock::dump): (JSC::CodeBlock::reparseForExceptionInfoIfNecessary): (JSC::CodeBlock::hasGlobalResolveInstructionAtBytecodeOffset): (JSC::CodeBlock::hasGlobalResolveInfoAtBytecodeOffset):
• bytecode/CodeBlock.h: (JSC::JITCodeRef::JITCodeRef): (JSC::GlobalResolveInfo::GlobalResolveInfo): (JSC::CodeBlock::getBytecodeIndex): (JSC::CodeBlock::addGlobalResolveInstruction): (JSC::CodeBlock::addGlobalResolveInfo): (JSC::CodeBlock::addFunctionRegisterInfo): (JSC::CodeBlock::hasExceptionInfo): (JSC::CodeBlock::pcVector): (JSC::EvalCodeBlock::EvalCodeBlock): (JSC::EvalCodeBlock::baseScopeDepth):
• bytecode/Opcode.h:
• bytecompiler/BytecodeGenerator.cpp: (JSC::BytecodeGenerator::BytecodeGenerator): (JSC::BytecodeGenerator::emitResolve): (JSC::BytecodeGenerator::emitGetScopedVar):
• bytecompiler/BytecodeGenerator.h: (JSC::BytecodeGenerator::setRegeneratingForExceptionInfo):
• interpreter/Interpreter.cpp: (JSC::bytecodeOffsetForPC): (JSC::Interpreter::unwindCallFrame): (JSC::Interpreter::privateExecute): (JSC::Interpreter::retrieveLastCaller): (JSC::Interpreter::cti_op_instanceof): (JSC::Interpreter::cti_op_call_NotJSFunction): (JSC::Interpreter::cti_op_resolve): (JSC::Interpreter::cti_op_construct_NotJSConstruct): (JSC::Interpreter::cti_op_resolve_func): (JSC::Interpreter::cti_op_resolve_skip): (JSC::Interpreter::cti_op_resolve_global): (JSC::Interpreter::cti_op_resolve_with_base): (JSC::Interpreter::cti_op_throw): (JSC::Interpreter::cti_op_in): (JSC::Interpreter::cti_vm_throw):
• jit/JIT.cpp: (JSC::JIT::privateCompile):
• parser/Nodes.cpp: (JSC::EvalNode::generateBytecode): (JSC::EvalNode::bytecodeForExceptionInfoReparse): (JSC::FunctionBodyNode::bytecodeForExceptionInfoReparse):
• parser/Nodes.h:

File:

• trunk/JavaScriptCore/bytecompiler/BytecodeGenerator.h (modified) (3 diffs)

trunk/JavaScriptCore/bytecompiler/BytecodeGenerator.h

@@ -330 +330 @@
         CodeType codeType() const { return m_codeType; }
 
-        void setRegeneratingForExceptionInfo() { m_regeneratingForExceptionInfo = true; }
+        void setRegeneratingForExceptionInfo(CodeBlock* originalCodeBlock)
+        {
+            m_regeneratingForExceptionInfo = true;
+            m_codeBlockBeingRegeneratedFrom = originalCodeBlock;
+        }
 
     private:
@@ -422 +426 @@
         bool m_shouldEmitDebugHooks;
         bool m_shouldEmitProfileHooks;
-
-        bool m_regeneratingForExceptionInfo;
 
         const ScopeChain* m_scopeChain;
@@ -466 +468 @@
         OpcodeID m_lastOpcodeID;
 
-#ifndef NDEBUG
-        static bool s_dumpsGeneratedCode;
-#endif
-
         unsigned m_emitNodeDepth;
+
+        bool m_regeneratingForExceptionInfo;
+        CodeBlock* m_codeBlockBeingRegeneratedFrom;
 
         static const unsigned s_maxEmitNodeDepth = 10000;