Changeset 59161 in webkit for trunk/JavaScriptCore/runtime/Operations.h

Timestamp:

May 11, 2010, 11:42:46 AM (15 years ago)

Author:

[email protected]

Message:

Start using ropes in String.prototype.replace.

Reviewed by Oliver Hunt and Darin Adler.

1%-1.5% speedup on SunSpider.

• runtime/JSString.cpp:

(JSC::JSString::resolveRope): Updated for RopeImpl refactoring.

(JSC::JSString::replaceCharacter): Added a replaceCharacter function, which creates
a rope for the resulting replacement.

• runtime/JSString.h: A few changes here:

(JSC::):
(JSC::RopeBuilder::RopeIterator::RopeIterator):
(JSC::RopeBuilder::RopeIterator::operator++):
(JSC::RopeBuilder::RopeIterator::operator*):
(JSC::RopeBuilder::RopeIterator::operator!=):
(JSC::RopeBuilder::RopeIterator::WorkItem::WorkItem):
(JSC::RopeBuilder::RopeIterator::WorkItem::operator!=):
(JSC::RopeBuilder::RopeIterator::skipRopes): Created a RopeIterator abstraction.
We use this to do a substring find without having to resolve the rope.
(We could use this iterator when resolving ropes, too, but resolving
ropes backwards is usually more efficient.)

(JSC::RopeBuilder::JSString): Added constructors for 2 & 3 UStrings.

(JSC::RopeBuilder::appendValueInConstructAndIncrementLength):
(JSC::RopeBuilder::size): Updated for RopeImpl refactoring.

• runtime/Operations.h: Updated for RopeImpl refactoring.

(JSC::jsString): Added jsString functions for 2 & 3 UStrings.

• runtime/RopeImpl.cpp:

(JSC::RopeImpl::derefFibersNonRecursive):

• runtime/RopeImpl.h:

(JSC::RopeImpl::initializeFiber):
(JSC::RopeImpl::size):
(JSC::RopeImpl::fibers):
(JSC::RopeImpl::deref):
(JSC::RopeImpl::RopeImpl): A little refactoring to make this patch easier:
Moved statics to the top of the class; put multi-statement functions on
multiple lines; renamed "fiberCount" to "size" to match other collections;
changed the "fibers" accessor to return the fibers buffer, instead of an
item in the buffer, to make iteration easier.

• runtime/StringPrototype.cpp:

(JSC::stringProtoFuncReplace): Don't resolve a rope unless we need to. Do
use our new replaceCharacter function if possible. Do use a rope to
represent splicing three strings together.

File:

• trunk/JavaScriptCore/runtime/Operations.h (modified) (7 diffs)

trunk/JavaScriptCore/runtime/Operations.h

@@ -47 +47 @@
             return throwOutOfMemoryError(exec);
 
-        unsigned fiberCount = s1->fiberCount() + s2->fiberCount();
+        unsigned fiberCount = s1->size() + s2->size();
         JSGlobalData* globalData = &exec->globalData();
 
@@ -72 +72 @@
             return throwOutOfMemoryError(exec);
 
-        unsigned fiberCount = 1 + s2->fiberCount();
+        unsigned fiberCount = 1 + s2->size();
         JSGlobalData* globalData = &exec->globalData();
 
@@ -97 +97 @@
             return throwOutOfMemoryError(exec);
 
-        unsigned fiberCount = s1->fiberCount() + 1;
+        unsigned fiberCount = s1->size() + 1;
         JSGlobalData* globalData = &exec->globalData();
 
@@ -109 +109 @@
         ropeBuilder.append(u2);
         return new (globalData) JSString(globalData, ropeBuilder.release());
+    }
+
+    ALWAYS_INLINE JSValue jsString(ExecState* exec, const UString& u1, const UString& u2)
+    {
+        unsigned length1 = u1.size();
+        if (!length1)
+            return jsString(exec, u2);
+        unsigned length2 = u2.size();
+        if (!length2)
+            return jsString(exec, u1);
+        if ((length1 + length2) < length1)
+            return throwOutOfMemoryError(exec);
+
+        JSGlobalData* globalData = &exec->globalData();
+        return new (globalData) JSString(globalData, u1, u2);
+    }
+
+    ALWAYS_INLINE JSValue jsString(ExecState* exec, const UString& u1, const UString& u2, const UString& u3)
+    {
+        unsigned length1 = u1.size();
+        unsigned length2 = u2.size();
+        unsigned length3 = u3.size();
+        if (!length1)
+            return jsString(exec, u2, u3);
+        if (!length2)
+            return jsString(exec, u1, u3);
+        if (!length3)
+            return jsString(exec, u1, u2);
+
+        if ((length1 + length2) < length1)
+            return throwOutOfMemoryError(exec);
+        if ((length1 + length2 + length3) < length3)
+            return throwOutOfMemoryError(exec);
+
+        JSGlobalData* globalData = &exec->globalData();
+        return new (globalData) JSString(globalData, u1, u2, u3);
     }
 
@@ -119 +155 @@
             JSValue v = strings[i].jsValue();
             if (LIKELY(v.isString()))
-                fiberCount += asString(v)->fiberCount();
+                fiberCount += asString(v)->size();
             else
                 ++fiberCount;
@@ -158 +194 @@
         unsigned fiberCount = 0;
         if (LIKELY(thisValue.isString()))
-            fiberCount += asString(thisValue)->fiberCount();
+            fiberCount += asString(thisValue)->size();
         else
             ++fiberCount;
@@ -164 +200 @@
             JSValue v = args.at(i);
             if (LIKELY(v.isString()))
-                fiberCount += asString(v)->fiberCount();
+                fiberCount += asString(v)->size();
             else
                 ++fiberCount;