Changeset 221192 in webkit

Timestamp:

Aug 25, 2017, 10:27:46 AM (9 years ago)

Author:

keith_miller@apple.com

Message:

Explore increasing max JSString::m_length to UINT_MAX.
​https://bugs.webkit.org/show_bug.cgi?id=163955
<rdar://problem/32001499>

Reviewed by JF Bastien.

This can cause us to release assert on some code paths. I don't
see a reason to maintain this restriction.

• runtime/JSString.h:

(JSC::JSString::length const):
(JSC::JSString::setLength):
(JSC::JSString::isValidLength): Deleted.

• runtime/JSStringBuilder.h:

(JSC::jsMakeNontrivialString):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• runtime/JSString.h (modified) (2 diffs)
• runtime/JSStringBuilder.h (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2017-08-25  Keith Miller  <keith_miller@apple.com>
+
+        Explore increasing max JSString::m_length to UINT_MAX.
+        https://bugs.webkit.org/show_bug.cgi?id=163955
+        <rdar://problem/32001499>
+
+        Reviewed by JF Bastien.
+
+        This can cause us to release assert on some code paths. I don't
+        see a reason to maintain this restriction.
+
+        * runtime/JSString.h:
+        (JSC::JSString::length const):
+        (JSC::JSString::setLength):
+        (JSC::JSString::isValidLength): Deleted.
+        * runtime/JSStringBuilder.h:
+        (JSC::jsMakeNontrivialString):
+
 2017-08-24  Commit Queue  <commit-queue@webkit.org>
 

trunk/Source/JavaScriptCore/runtime/JSString.h

@@ -165 +165 @@
     const StringImpl* tryGetValueImpl() const;
     ALWAYS_INLINE unsigned length() const { return m_length; }
-    ALWAYS_INLINE static bool isValidLength(size_t length)
-    {
-        // While length is of type unsigned, the runtime and compilers are all
-        // expecting that m_length is a positive value <= INT_MAX.
-        // FIXME: Look into making the max length UINT_MAX to match StringImpl's max length.
-        // https://bugs.webkit.org/show_bug.cgi?id=163955
-        return length <= std::numeric_limits<int32_t>::max();
-    }
 
     JSValue toPrimitive(ExecState*, PreferredPrimitiveType) const;
@@ -220 +212 @@
     ALWAYS_INLINE void setLength(unsigned length)
     {
-        RELEASE_ASSERT(isValidLength(length));
         m_length = length;
     }

trunk/Source/JavaScriptCore/runtime/JSStringBuilder.h

@@ -132 +132 @@
     auto scope = DECLARE_THROW_SCOPE(vm);
     String result = tryMakeString(string, strings...);
-    if (UNLIKELY(!result || !JSString::isValidLength(result.length())))
+    if (UNLIKELY(!result))
         return throwOutOfMemoryError(exec, scope);
     return jsNontrivialString(exec, WTFMove(result));