Changeset 36483 in webkit for trunk/JavaScriptCore/kjs/operations.cpp

Timestamp:

Sep 15, 2008, 11:08:51 PM (17 years ago)

Author:

[email protected]

Message:

2008-09-15 Maciej Stachowiak <​[email protected]>

Reviewed by Cameron Zwarich.

• speed up the === and !== operators by choosing the fast cases better

No effect on SunSpider but speeds up the V8 EarlyBoyer benchmark about 4%.

• VM/Machine.cpp: (JSC::Machine::privateExecute): (JSC::Machine::cti_op_stricteq): (JSC::Machine::cti_op_nstricteq):
• kjs/JSImmediate.h: (JSC::JSImmediate::areBothImmediate):
• kjs/operations.cpp: (JSC::strictEqual): (JSC::strictEqualSlowCase):
• kjs/operations.h:

File:

• trunk/JavaScriptCore/kjs/operations.cpp (modified) (1 diff)

trunk/JavaScriptCore/kjs/operations.cpp

@@ -102 +102 @@
 bool strictEqual(JSValue* v1, JSValue* v2)
 {
+    if (JSImmediate::areBothImmediate(v1, v2))
+        return v1 == v2;
+
+    if (JSImmediate::isEitherImmediate(v1, v2) & v1 != JSImmediate::from(0) & v2 != JSImmediate::from(0))
+        return false;
+
+    return strictEqualSlowCase(v1, v2);
+}
+
+bool strictEqualSlowCase(JSValue* v1, JSValue* v2)
+{
+    ASSERT(!JSImmediate::areBothImmediate(v1, v2));
+
     if (JSImmediate::isEitherImmediate(v1, v2)) {
-        if (v1 == v2)
-            return true;
+        // pointers can't be equal since one is immediate and one isn't
+        ASSERT(v1 != v2);
+        ASSERT(v1 == JSImmediate::zeroImmediate() || v2 == JSImmediate::zeroImmediate());
 
         // The reason we can't just return false here is that 0 === -0,
         // and while the former is an immediate number, the latter is not.
-        if (v1 == JSImmediate::from(0))
-            return !JSImmediate::isImmediate(v2)
-                && static_cast<JSCell*>(v2)->isNumber()
-                && static_cast<JSNumberCell*>(v2)->value() == 0;
-        return v2 == JSImmediate::from(0)
-            && !JSImmediate::isImmediate(v1)
-            && static_cast<JSCell*>(v1)->isNumber()
-            && static_cast<JSNumberCell*>(v1)->value() == 0;
+        if (v1 == JSImmediate::zeroImmediate())
+            return static_cast<JSCell*>(v2)->isNumber() && static_cast<JSNumberCell*>(v2)->value() == 0;
+        return static_cast<JSCell*>(v1)->isNumber() && static_cast<JSNumberCell*>(v1)->value() == 0;
     }
 
-    if (static_cast<JSCell*>(v1)->isNumber())
+    if (static_cast<JSCell*>(v1)->isNumber()) {
         return static_cast<JSCell*>(v2)->isNumber()
             && static_cast<JSNumberCell*>(v1)->value() == static_cast<JSNumberCell*>(v2)->value();
+    }
 
-    if (static_cast<JSCell*>(v1)->isString())
+    if (static_cast<JSCell*>(v1)->isString()) {
         return static_cast<JSCell*>(v2)->isString()
             && static_cast<JSString*>(v1)->value() == static_cast<JSString*>(v2)->value();
+    }
 
     return v1 == v2;