Changeset 58986 in webkit for trunk/JavaScriptCore/bytecompiler/NodesCodegen.cpp

Timestamp:

May 7, 2010, 5:05:00 PM (15 years ago)

Author:

[email protected]

Message:

2010-05-07 Oliver Hunt <​[email protected]>

Reviewed by Geoffrey Garen.

Optimize access to the global object from a function that uses eval
​https://bugs.webkit.org/show_bug.cgi?id=38644

Add op_resolve_global_dynamic, a variant of op_resolve_global that
checks each node in the scope chain for dynamically inserted properties
and falls back to the normal resolve logic in that case.

• JavaScriptCore.exp:
• bytecode/CodeBlock.cpp: (JSC::isGlobalResolve): (JSC::CodeBlock::printStructures): (JSC::CodeBlock::dump): (JSC::CodeBlock::derefStructures):
• bytecode/Opcode.h:
• bytecompiler/BytecodeGenerator.cpp: (JSC::BytecodeGenerator::findScopedProperty):

Now take an additional reference parameter to used to indicate that
there were nodes that may gain dynamic properties

(JSC::BytecodeGenerator::emitResolve):
(JSC::BytecodeGenerator::emitResolveBase):
(JSC::BytecodeGenerator::emitResolveWithBase):

deal with additional argument to findScopedProperty

• bytecompiler/BytecodeGenerator.h:
• bytecompiler/NodesCodegen.cpp: (JSC::FunctionCallResolveNode::emitBytecode): (JSC::PostfixResolveNode::emitBytecode): (JSC::PrefixResolveNode::emitBytecode): (JSC::ReadModifyResolveNode::emitBytecode): (JSC::AssignResolveNode::emitBytecode):

These functions use findScopedProperty directly in order to
optimise lookup. They cannot trivially handle any degree of
dynamism in the lookup so we just give up in such case.

• interpreter/Interpreter.cpp: (JSC::Interpreter::resolveGlobalDynamic): (JSC::Interpreter::execute): (JSC::Interpreter::privateExecute):
• interpreter/Interpreter.h:
• jit/JIT.cpp: (JSC::JIT::privateCompileMainPass): (JSC::JIT::privateCompileSlowCases):
• jit/JIT.h:
• jit/JITOpcodes.cpp: (JSC::JIT::emit_op_resolve_global): (JSC::JIT::emit_op_resolve_global_dynamic): (JSC::JIT::emitSlow_op_resolve_global): (JSC::JIT::emitSlow_op_resolve_global_dynamic):

Happily resolve_global_dynamic can share the slow case!

• jit/JITStubs.h: (JSC::):
• runtime/JSActivation.cpp: (JSC::JSActivation::isDynamicScope):
• runtime/JSActivation.h:
• runtime/JSGlobalObject.cpp: (JSC::JSGlobalObject::isDynamicScope):
• runtime/JSGlobalObject.h:
• runtime/JSStaticScopeObject.cpp: (JSC::JSStaticScopeObject::isDynamicScope):
• runtime/JSStaticScopeObject.h:
• runtime/JSVariableObject.h:

File:

• trunk/JavaScriptCore/bytecompiler/NodesCodegen.cpp (modified) (5 diffs)

trunk/JavaScriptCore/bytecompiler/NodesCodegen.cpp

@@ -352 +352 @@
     size_t depth = 0;
     JSObject* globalObject = 0;
-    if (generator.findScopedProperty(m_ident, index, depth, false, globalObject) && index != missingSymbolMarker()) {
+    bool requiresDynamicChecks = false;
+    if (generator.findScopedProperty(m_ident, index, depth, false, requiresDynamicChecks, globalObject) && index != missingSymbolMarker() && !requiresDynamicChecks) {
         RefPtr<RegisterID> func = generator.emitGetScopedVar(generator.newTemporary(), depth, index, globalObject);
         RefPtr<RegisterID> thisRegister = generator.emitLoad(generator.newTemporary(), jsNull());
@@ -525 +526 @@
     size_t depth = 0;
     JSObject* globalObject = 0;
-    if (generator.findScopedProperty(m_ident, index, depth, true, globalObject) && index != missingSymbolMarker()) {
+    bool requiresDynamicChecks = false;
+    if (generator.findScopedProperty(m_ident, index, depth, true, requiresDynamicChecks, globalObject) && index != missingSymbolMarker() && !requiresDynamicChecks) {
         RefPtr<RegisterID> value = generator.emitGetScopedVar(generator.newTemporary(), depth, index, globalObject);
         RegisterID* oldValue;
@@ -711 +713 @@
     size_t depth = 0;
     JSObject* globalObject = 0;
-    if (generator.findScopedProperty(m_ident, index, depth, false, globalObject) && index != missingSymbolMarker()) {
+    bool requiresDynamicChecks = false;
+    if (generator.findScopedProperty(m_ident, index, depth, false, requiresDynamicChecks, globalObject) && index != missingSymbolMarker() && !requiresDynamicChecks) {
         RefPtr<RegisterID> propDst = generator.emitGetScopedVar(generator.tempDestination(dst), depth, index, globalObject);
         emitPreIncOrDec(generator, propDst.get(), m_operator);
@@ -1133 +1136 @@
     size_t depth = 0;
     JSObject* globalObject = 0;
-    if (generator.findScopedProperty(m_ident, index, depth, true, globalObject) && index != missingSymbolMarker()) {
+    bool requiresDynamicChecks = false;
+    if (generator.findScopedProperty(m_ident, index, depth, true, requiresDynamicChecks, globalObject) && index != missingSymbolMarker() && !requiresDynamicChecks) {
         RefPtr<RegisterID> src1 = generator.emitGetScopedVar(generator.tempDestination(dst), depth, index, globalObject);
         RegisterID* result = emitReadModifyAssignment(generator, generator.finalDestination(dst, src1.get()), src1.get(), m_right, m_operator, OperandTypes(ResultType::unknownType(), m_right->resultDescriptor()));
@@ -1162 +1166 @@
     size_t depth = 0;
     JSObject* globalObject = 0;
-    if (generator.findScopedProperty(m_ident, index, depth, true, globalObject) && index != missingSymbolMarker()) {
+    bool requiresDynamicChecks = false;
+    if (generator.findScopedProperty(m_ident, index, depth, true, requiresDynamicChecks, globalObject) && index != missingSymbolMarker() && !requiresDynamicChecks) {
         if (dst == generator.ignoredResult())
             dst = 0;