Changeset 103023 in webkit for trunk/Source/JavaScriptCore/bytecode

Timestamp:

Dec 15, 2011, 9:32:58 PM (13 years ago)

Author:

[email protected]

Message:

Value profiling should distinguished between NaN and non-NaN doubles
​https://bugs.webkit.org/show_bug.cgi?id=74682

Reviewed by Gavin Barraclough.

Added PredictDoubleReal and PredictDoubleNaN. PredictDouble is now the union
of the two.

• bytecode/PredictedType.cpp:

(JSC::predictionToString):
(JSC::predictionFromValue):

• bytecode/PredictedType.h:

(JSC::isDoubleRealPrediction):
(JSC::isDoublePrediction):

Location:

trunk/Source/JavaScriptCore/bytecode

Files:

• PredictedType.cpp (modified) (2 diffs)
• PredictedType.h (modified) (2 diffs)

trunk/Source/JavaScriptCore/bytecode/PredictedType.cpp

@@ -129 +129 @@
         isTop = false;
     
-    if (value & PredictDouble)
-        ptr.strcat("Double");
+    if (value & PredictDoubleReal)
+        ptr.strcat("Doublereal");
+    else
+        isTop = false;
+    
+    if (value & PredictDoubleNaN)
+        ptr.strcat("Doublenan");
     else
         isTop = false;
@@ -213 +218 @@
     if (value.isInt32())
         return PredictInt32;
-    if (value.isDouble())
-        return PredictDouble;
+    if (value.isDouble()) {
+        double number = value.asNumber();
+        if (number == number)
+            return PredictDoubleReal;
+        return PredictDoubleNaN;
+    }
     if (value.isCell())
         return predictionFromCell(value.asCell());

trunk/Source/JavaScriptCore/bytecode/PredictedType.h

@@ -56 +56 @@
 static const PredictedType PredictCell          = 0x00007fff; // It's definitely a JSCell.
 static const PredictedType PredictInt32         = 0x00008000; // It's definitely an Int32.
-static const PredictedType PredictDouble        = 0x00010000; // It's definitely a Double.
-static const PredictedType PredictNumber        = 0x00018000; // It's either an Int32 or a Double.
-static const PredictedType PredictBoolean       = 0x00020000; // It's definitely a Boolean.
+static const PredictedType PredictDoubleReal    = 0x00010000; // It's definitely a non-NaN double.
+static const PredictedType PredictDoubleNaN     = 0x00020000; // It's definitely a NaN.
+static const PredictedType PredictDouble        = 0x00030000; // It's either a non-NaN or a NaN double.
+static const PredictedType PredictNumber        = 0x00038000; // It's either an Int32 or a Double.
+static const PredictedType PredictBoolean       = 0x00040000; // It's definitely a Boolean.
 static const PredictedType PredictOther         = 0x40000000; // It's definitely none of the above.
 static const PredictedType PredictTop           = 0x7fffffff; // It can be any of the above.
@@ -160 +162 @@
 }
 
+inline bool isDoubleRealPrediction(PredictedType value)
+{
+    return value == PredictDoubleReal;
+}
+
 inline bool isDoublePrediction(PredictedType value)
 {
-    return value == PredictDouble;
+    return (value & PredictDouble) == value;
 }