Changeset 282239 in webkit for trunk/Source/JavaScriptCore/jit/JIT.cpp

Timestamp:

Sep 9, 2021, 2:36:38 PM (4 years ago)

Author:

[email protected]

Message:

[JSC] Optimize op_get_property_enumerator further
​https://bugs.webkit.org/show_bug.cgi?id=230086

Reviewed by Saam Barati.

JSTests:

• stress/for-in-cell-other.js: Added.

(shouldBe):
(forIn):

• stress/for-in-null-undefined.js: Added.

(shouldBe):
(forIn):

Source/JavaScriptCore:

1. This patch adds fast path of op_get_property_enumerator to LLInt and Baseline. Previously, we only had this fast path in DFG and FTL.
2. From the profiled data, Speedometer2/React-Redux-TodoMVC has GetPropertyEnumerator(CellOrOther). However, DFG and FTL only optimized GetPropertyEnumerator(Cell). We add CellOrOther and Other cases: if the argument is Other, then we can constant fold it to the empty enumerator. If the argument is CellOrOther, we can check first, and return empty enumerator for Other case.
3. This patch also cleans up StructureRareData lookup by introducing StructureType to JSType.

---

| subtest | ms | ms | b / a | pValue (significance using False Discovery Rate) |

---

| Elm-TodoMVC |117.388333 |117.680000 |1.002485 | 0.269607 |
| VueJS-TodoMVC |24.918333 |24.651667 |0.989298 | 0.157665 |
| EmberJS-TodoMVC |126.430000 |126.296667 |0.998945 | 0.673803 |
| BackboneJS-TodoMVC |48.695000 |48.411667 |0.994181 | 0.019164 |
| Preact-TodoMVC |17.268333 |17.511667 |1.014091 | 0.199775 |
| AngularJS-TodoMVC |130.246667 |129.850000 |0.996954 | 0.261543 |
| Vanilla-ES2015-TodoMVC |63.626667 |63.611667 |0.999764 | 0.912112 |
| Inferno-TodoMVC |63.881667 |63.600000 |0.995591 | 0.385440 |
| Flight-TodoMVC |78.158333 |78.606667 |1.005736 | 0.284177 |
| Angular2-TypeScript-TodoMVC |39.448333 |39.411667 |0.999071 | 0.890825 |
| VanillaJS-TodoMVC |50.858333 |51.130000 |1.005342 | 0.195409 |
| jQuery-TodoMVC |225.318333 |226.256667 |1.004164 | 0.011190 |
| EmberJS-Debug-TodoMVC |340.150000 |338.450000 |0.995002 | 0.000063 (significant) |
| React-TodoMVC |85.703333 |85.606667 |0.998872 | 0.549298 |
| React-Redux-TodoMVC |141.985000 |140.418333 |0.988966 | 0.000000 (significant) |
| Vanilla-ES2015-Babel-Webpack-TodoMVC |61.505000 |61.705000 |1.003252 | 0.079817 |

---

a mean = 260.98021
b mean = 261.16020
pValue = 0.4985041089
(Bigger means are better.)
1.001 times better
Results ARE NOT significant

• bytecode/SpeculatedType.cpp:

(JSC::dumpSpeculation):

• dfg/DFGFixupPhase.cpp:

(JSC::DFG::FixupPhase::fixupNode):

• dfg/DFGSpeculativeJIT.cpp:

(JSC::DFG::SpeculativeJIT::compileGetPropertyEnumerator):
(JSC::DFG::SpeculativeJIT::compileObjectKeysOrObjectGetOwnPropertyNames):

• ftl/FTLLowerDFGToB3.cpp:

(JSC::FTL::DFG::LowerDFGToB3::compileObjectKeysOrObjectGetOwnPropertyNames):
(JSC::FTL::DFG::LowerDFGToB3::compileCompareStrictEq):

• jit/AssemblyHelpers.h:

(JSC::AssemblyHelpers::branchIfStructure):
(JSC::AssemblyHelpers::branchIfNotStructure):

• jit/JIT.cpp:

(JSC::JIT::privateCompileMainPass):

• jit/JIT.h:
• jit/JITPropertyAccess.cpp:

(JSC::JIT::emit_op_get_property_enumerator):

• jit/JITPropertyAccess32_64.cpp:

(JSC::JIT::emit_op_get_property_enumerator):

• llint/LowLevelInterpreter.asm:
• llint/LowLevelInterpreter32_64.asm:
• llint/LowLevelInterpreter64.asm:
• runtime/BrandedStructure.cpp:

(JSC::BrandedStructure::create):

• runtime/JSType.cpp:

(WTF::printInternal):

• runtime/JSType.h:
• runtime/Structure.cpp:

(JSC::Structure::Structure):
(JSC::Structure::create):

• runtime/Structure.h:

(JSC::Structure::isRareData):
(JSC::Structure::isRareData const): Deleted.

• runtime/StructureInlines.h:

(JSC::Structure::create):
(JSC::Structure::createStructure):

• runtime/StructureRareData.h:
• runtime/VM.cpp:

(JSC::VM::VM):

File:

• trunk/Source/JavaScriptCore/jit/JIT.cpp (modified) (2 diffs)

trunk/Source/JavaScriptCore/jit/JIT.cpp

@@ -309 +309 @@
         DEFINE_SLOW_OP(new_array_buffer)
         DEFINE_SLOW_OP(spread)
-        DEFINE_SLOW_OP(get_property_enumerator)
         DEFINE_SLOW_OP(create_direct_arguments)
         DEFINE_SLOW_OP(create_scoped_arguments)
@@ -363 +362 @@
         DEFINE_OP(op_get_by_id_direct)
         DEFINE_OP(op_get_by_val)
+        DEFINE_OP(op_get_property_enumerator)
         DEFINE_OP(op_enumerator_next)
         DEFINE_OP(op_enumerator_get_by_val)