Changeset 100202 in webkit for trunk/Source/JavaScriptCore/runtime/JSString.h

Timestamp:

Nov 14, 2011, 3:51:06 PM (14 years ago)

Author:

[email protected]

Message:

Towards 8 bit strings - Add 8 bit handling to JSString Ropes
​https://bugs.webkit.org/show_bug.cgi?id=72317

Added bit to track that a rope is made up of all 8 bit fibers.
Created an 8 bit path (fast and slow cases) to handle 8 bit
only ropes.

Reviewed by Oliver Hunt.

• runtime/JSString.cpp:

(JSC::JSString::resolveRope):
(JSC::JSString::resolveRopeSlowCase8):
(JSC::JSString::resolveRopeSlowCase16):

• runtime/JSString.h:

(JSC::RopeBuilder::finishCreation):
(JSC::RopeBuilder::is8Bit):
(JSC::jsSubstring8):

File:

• trunk/Source/JavaScriptCore/runtime/JSString.h (modified) (9 diffs)

trunk/Source/JavaScriptCore/runtime/JSString.h

@@ -23 +23 @@
 #ifndef JSString_h
 #define JSString_h
-
 #include "CallFrame.h"
 #include "CommonIdentifiers.h"
@@ -86 +85 @@
                 m_jsString->m_fibers[m_index++].set(m_globalData, m_jsString, jsString);
                 m_jsString->m_length += jsString->m_length;
+                m_jsString->m_is8Bit = m_jsString->m_is8Bit && jsString->m_is8Bit;
             }
 
@@ -128 +128 @@
             Base::finishCreation(globalData);
             m_length = length;
+            m_is8Bit = m_value.impl()->is8Bit();
         }
 
@@ -135 +136 @@
             Base::finishCreation(globalData);
             m_length = length;
+            m_is8Bit = m_value.impl()->is8Bit();
             Heap::heap(this)->reportExtraMemoryCost(cost);
         }
@@ -142 +144 @@
             Base::finishCreation(globalData);
             m_length = s1->length() + s2->length();
+            m_is8Bit = (s1->is8Bit() && s2->is8Bit());
             m_fibers[0].set(globalData, this, s1);
             m_fibers[1].set(globalData, this, s2);
@@ -150 +153 @@
             Base::finishCreation(globalData);
             m_length = s1->length() + s2->length() + s3->length();
+            m_is8Bit = (s1->is8Bit() && s2->is8Bit() &&  s3->is8Bit());
             m_fibers[0].set(globalData, this, s1);
             m_fibers[1].set(globalData, this, s2);
@@ -245 +249 @@
 
         void resolveRope(ExecState*) const;
+        void resolveRopeSlowCase(ExecState*, LChar*) const;
         void resolveRopeSlowCase(ExecState*, UChar*) const;
         void outOfMemory(ExecState*) const;
@@ -257 +262 @@
 
         // A string is represented either by a UString or a rope of fibers.
+        bool m_is8Bit : 1;
         unsigned m_length;
         mutable UString m_value;
@@ -262 +268 @@
 
         bool isRope() const { return m_value.isNull(); }
+        bool is8Bit() const { return m_is8Bit; }
         UString& string() { ASSERT(!isRope()); return m_value; }