Changeset 68223 in webkit for trunk/JavaScriptCore/interpreter/Interpreter.cpp

Timestamp:

Sep 23, 2010, 5:52:52 PM (15 years ago)

Author:

[email protected]

Message:

2010-09-23 Oliver Hunt <​[email protected]>

Reviewed by Geoffrey Garen.

Delay construction of functions that aren't captured
​https://bugs.webkit.org/show_bug.cgi?id=46433

If a function isn't captured by an activation there's no
way it can be accessed indirectly, so we can delay the
construction until it's used (similar to what we do with
arguments). We rename the existing op_init_arguments to
op_init_lazy_reg and removed its implicit handling of
the anonymous argument register, and make op_new_function
take a parameter to indicate whether it should null check
the target slot before creating the function object.

• bytecode/CodeBlock.cpp: (JSC::CodeBlock::dump):
• bytecode/Opcode.h:
• bytecompiler/BytecodeGenerator.cpp: (JSC::BytecodeGenerator::BytecodeGenerator): (JSC::BytecodeGenerator::emitInitLazyRegister): (JSC::BytecodeGenerator::registerFor): (JSC::BytecodeGenerator::createLazyRegisterIfNecessary): (JSC::BytecodeGenerator::constRegisterFor): (JSC::BytecodeGenerator::emitNewFunction): (JSC::BytecodeGenerator::emitLazyNewFunction): (JSC::BytecodeGenerator::emitNewFunctionInternal):
• bytecompiler/BytecodeGenerator.h:
• interpreter/Interpreter.cpp: (JSC::Interpreter::privateExecute):
• jit/JIT.cpp: (JSC::JIT::privateCompileMainPass):
• jit/JIT.h:
• jit/JITOpcodes.cpp: (JSC::JIT::emit_op_init_lazy_reg): (JSC::JIT::emit_op_new_func):
• jit/JITOpcodes32_64.cpp: (JSC::JIT::emit_op_init_lazy_reg):
• parser/Nodes.h: (JSC::ScopeNode::needsActivationForMoreThanVariables):

File:

• trunk/JavaScriptCore/interpreter/Interpreter.cpp (modified) (3 diffs)

trunk/JavaScriptCore/interpreter/Interpreter.cpp

@@ -3613 +3613 @@
         int dst = vPC[1].u.operand;
         int func = vPC[2].u.operand;
-
-        callFrame->r(dst) = JSValue(codeBlock->functionDecl(func)->make(callFrame, callFrame->scopeChain()));
+        int shouldCheck = vPC[3].u.operand;
+
+        if (!shouldCheck || !callFrame->r(dst).jsValue())
+            callFrame->r(dst) = JSValue(codeBlock->functionDecl(func)->make(callFrame, callFrame->scopeChain()));
 
         vPC += OPCODE_LENGTH(op_new_func);
@@ -4138 +4140 @@
         NEXT_INSTRUCTION();
     }
-    DEFINE_OPCODE(op_init_arguments) {
-        /* create_arguments dst(r)
-
-           Initialises 'arguments' to JSValue().
+    DEFINE_OPCODE(op_init_lazy_reg) {
+        /* init_lazy_reg dst(r)
+
+           Initialises dst(r) to JSValue().
 
            This opcode appears only at the beginning of a code block.
@@ -4148 +4150 @@
 
         callFrame->r(dst) = JSValue();
-        callFrame->r(unmodifiedArgumentsRegister(dst)) = JSValue();
-        vPC += OPCODE_LENGTH(op_init_arguments);
+        vPC += OPCODE_LENGTH(op_init_lazy_reg);
         NEXT_INSTRUCTION();
     }