Changeset 183753 in webkit

Timestamp:

May 4, 2015 11:45:40 AM (9 years ago)

Author:

akling@apple.com

Message:

Make ExecState::vm() branchless in release builds.
<​https://webkit.org/b/144586>

Reviewed by Geoffrey Garen.

Avoid null checking the ExecState's callee() before getting the
VM from it. The code was already dereferencing it anyway, since we
know it's not gonna be null.

• runtime/JSCellInlines.h:

(JSC::ExecState::vm):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• runtime/JSCellInlines.h (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2015-05-04  Andreas Kling  <akling@apple.com>
+
+        Make ExecState::vm() branchless in release builds.
+        <https://webkit.org/b/144586>
+
+        Reviewed by Geoffrey Garen.
+
+        Avoid null checking the ExecState's callee() before getting the
+        VM from it. The code was already dereferencing it anyway, since we
+        know it's not gonna be null.
+
+        * runtime/JSCellInlines.h:
+        (JSC::ExecState::vm):
+
 2015-05-04  Basile Clement  <basile_clement@apple.com>
 

trunk/Source/JavaScriptCore/runtime/JSCellInlines.h

@@ -121 +121 @@
 inline VM& ExecState::vm() const
 {
+    ASSERT(callee());
     ASSERT(callee()->vm());
-    return *callee()->vm();
+    return *calleeAsValue().asCell()->vm();
 }