Changeset 207465 in webkit

Timestamp:

Oct 18, 2016 9:26:17 AM (8 years ago)

Author:

Yusuke Suzuki

Message:

[DOMJIT] Not emit exception case if it is not necessary
​https://bugs.webkit.org/show_bug.cgi?id=163589

Reviewed by Sam Weinig.

We should not emit exception case if we do not use the slow path calls.
For example, nodeType accessor does not use the slow path calls.

• bytecode/PolymorphicAccess.cpp:

(JSC::AccessCase::emitDOMJITGetter):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• bytecode/PolymorphicAccess.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2016-10-18  Yusuke Suzuki  <utatane.tea@gmail.com>
+
+        [DOMJIT] Not emit exception case if it is not necessary
+        https://bugs.webkit.org/show_bug.cgi?id=163589
+
+        Reviewed by Sam Weinig.
+
+        We should not emit exception case if we do not use the slow path calls.
+        For example, nodeType accessor does not use the slow path calls.
+
+        * bytecode/PolymorphicAccess.cpp:
+        (JSC::AccessCase::emitDOMJITGetter):
+
 2016-10-18  Caitlin Potter  <caitp@igalia.com>
 

trunk/Source/JavaScriptCore/bytecode/PolymorphicAccess.cpp

@@ -1536 +1536 @@
 
     CCallHelpers::JumpList exceptions = params.emitSlowPathCalls(state, registersToSpillForCCall, jit);
-    exceptions.link(&jit);
-    allocator.restoreReusedRegistersByPopping(jit, preservedState);
-    state.emitExplicitExceptionHandler();
+    if (!exceptions.empty()) {
+        exceptions.link(&jit);
+        allocator.restoreReusedRegistersByPopping(jit, preservedState);
+        state.emitExplicitExceptionHandler();
+    }
 }