Some final tiny optimisations for testing string equality.

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@3045 72102866-910b-0410-8b05-ffd578937521

Headers/gnustep/base/NSGCString.h

@@ -27,8 +27,12 @@
 #include <gnustep/base/preface.h>
 #include <Foundation/NSString.h>
 
-/* NSGCString and NSGMutableCString must have the same initial ivar layout
-   because of class_add_behavior() in NSGMutableCString's +initialize. */
+/*
+ *	NSGCString and NSGMutableCString must have the same initial ivar layout
+ *	because of class_add_behavior() in NSGMutableCString's +initialize
+ *	and because the various string classes (and NSGDictionary) examine and
+ *	set each others _hash ivar directly for performance reasons!
+ */
 
 @interface NSGCString : NSString
 {

Headers/gnustep/base/fast.x

@@ -92,7 +92,7 @@ typedef struct {
      *	String implementations.
      */
     unsigned		(*_NSString_hash)();
-    unsigned		(*_NSGString_hash)();
+    BOOL		(*_NSString_isEqualToString_)();
     BOOL		(*_NSGString_isEqual_)();
     BOOL		(*_NSGCString_isEqual_)();
 } fastImp;

Source/NSGCString.m

@@ -47,8 +47,7 @@
 - (unsigned) hash
 {
   if (_hash == 0)
-    if ((_hash = _fastImp._NSString_hash(self, @selector(hash))) == 0)
-      _hash = 0xffffffff;
+    _hash = _fastImp._NSString_hash(self, @selector(hash));
   return _hash;
 }
 
@@ -116,7 +115,6 @@
 
 - initWithCoder: aCoder
 {
-  [super initWithCoder:aCoder];
   [aCoder decodeValueOfObjCType:@encode(char*) at:&_contents_chars
 	  withName:NULL];
   _count = strlen(_contents_chars);
@@ -270,20 +268,22 @@
       if (_count != other->_count)
 	return NO;
       if (_hash == 0)
-         if ((_hash = _fastImp._NSString_hash(self, @selector(hash))) == 0)
-           _hash = 0xffffffff;
+         _hash = _fastImp._NSString_hash(self, @selector(hash));
       if (other->_hash == 0)
-         _fastImp._NSGString_hash(other, @selector(hash));
+         other->_hash = _fastImp._NSString_hash(other, @selector(hash));
       if (_hash != other->_hash)
 	return NO;
       if (memcmp(_contents_chars, other->_contents_chars, _count) != 0)
 	return NO;
       return YES;
     }
-  else if ([c isKindOfClass: [NSString class]])
-    return [super isEqualToString: (NSString*)anObject];
+  else if (c == nil)
+    return NO;
+  else if (fastClassIsKindOfClass(c, _fastCls._NSString))
+    return _fastImp._NSString_isEqualToString_(self,
+		@selector(isEqualToString:), anObject);
   else
-    return [super isEqual: anObject];
+    return NO;
 }
 
 - (BOOL) isEqualToString: (NSString*)aString
@@ -302,18 +302,22 @@
       if (_count != other->_count)
 	return NO;
       if (_hash == 0)
-        if ((_hash = _fastImp._NSString_hash(self, @selector(hash))) == 0)
-          _hash = 0xffffffff;
+        _hash = _fastImp._NSString_hash(self, @selector(hash));
       if (other->_hash == 0)
-         _fastImp._NSGString_hash(other, @selector(hash));
+         other->_hash = _fastImp._NSString_hash(other, @selector(hash));
       if (_hash != other->_hash)
 	return NO;
       if (memcmp(_contents_chars, other->_contents_chars, _count) != 0)
 	return NO;
       return YES;
     }
+  else if (c == nil)
+    return NO;
+  else if (fastClassIsKindOfClass(c, _fastCls._NSString))
+    return _fastImp._NSString_isEqualToString_(self,
+		@selector(isEqualToString:), aString);
   else
-    return [super isEqualToString: aString];
+    return NO;
 }
 
 

Source/NSGDictionary.m

@@ -55,10 +55,11 @@ myHash(NSObject *obj)
 	    c == _fastCls._NSGString ||
 	    c == _fastCls._NSGMutableString) {
 
-	    if (((dictAccessToStringHack)obj)->_hash != 0) {
-		return ((dictAccessToStringHack)obj)->_hash;
+	    if (((dictAccessToStringHack)obj)->_hash == 0) {
+	        ((dictAccessToStringHack)obj)->_hash =
+	            _fastImp._NSString_hash(obj, @selector(hash));
 	    }
-	    return  _fastImp._NSGString_hash(obj, @selector(hash));
+	    return ((dictAccessToStringHack)obj)->_hash;
 	}
     }
     return [obj hash];

Source/NSGString.m

@@ -57,8 +57,7 @@
 - (unsigned) hash
 {
   if (_hash == 0)
-    if ((_hash = _fastImp._NSString_hash(self, @selector(hash))) == 0)
-      _hash = 0xffffffff;
+    _hash = _fastImp._NSString_hash(self, @selector(hash));
   return _hash;
 }
 
@@ -70,20 +69,28 @@
   if (anObject == nil)
     return NO;
   c = fastClassOfInstance(anObject);
-  if (c == _fastCls._NSGString || c == _fastCls._NSGMutableString)
+  if (c == _fastCls._NSGString || c == _fastCls._NSGMutableString ||
+      c == _fastCls._NSGCString || c == _fastCls._NSGMutableCString ||
+      c == _fastCls._NXConstantString)
     {
       NSGString	*other = (NSGString*)anObject;
 
       if (_hash == 0)
-        _fastImp._NSGString_hash(self, @selector(hash));
+        _hash = _fastImp._NSString_hash(self, @selector(hash));
       if (other->_hash == 0)
-        _fastImp._NSGString_hash(other, @selector(hash));
+        other->_hash = _fastImp._NSString_hash(other, @selector(hash));
       if (_hash != other->_hash)
 	return NO;
-      return [self isEqualToString: other];
+      return _fastImp._NSString_isEqualToString_(self,
+		@selector(isEqualToString:), other);
     }
+  else if (c == nil)
+    return NO;
+  else if (fastClassIsKindOfClass(c, _fastCls._NSString))
+    return _fastImp._NSString_isEqualToString_(self,
+		@selector(isEqualToString:), anObject);
   else
-    return [super isEqual: anObject];
+    return NO;
 }
 
 // Initializing Newly Allocated Strings
@@ -231,7 +238,6 @@
 
 - (void) encodeWithCoder: aCoder
 {
-  [super encodeWithCoder:aCoder];  // *** added this
   [aCoder encodeValueOfObjCType:@encode(int) at:&_count
  	  withName:@"Concrete String count"];
   [aCoder encodeArrayOfObjCType:@encode(unichar)
@@ -242,7 +248,6 @@
 
 - initWithCoder: aCoder
 {
-  [super initWithCoder:aCoder];
   [aCoder decodeValueOfObjCType:@encode(int) at:&_count
   	  withName:NULL];
   OBJC_MALLOC(_contents_chars, unichar, _count+1);

Source/NSObject.m

@@ -47,19 +47,22 @@ void	_fastBuildCache()
   /*
    *	Cache some classes for quick access later.
    */
+
   _fastCls._NSString = [NSString class];
   _fastCls._NSGString = [NSGString class];
   _fastCls._NSGMutableString = [NSGMutableString class];
   _fastCls._NSGCString = [NSGCString class];
   _fastCls._NSGMutableCString = [NSGMutableCString class];
   _fastCls._NXConstantString = [NXConstantString class];
+
   /*
    *	Cache some method implementations for quick access later.
    */
+
   _fastImp._NSString_hash = (unsigned (*)())[_fastCls._NSString
 	    instanceMethodForSelector: @selector(hash)];
-  _fastImp._NSGString_hash = (unsigned (*)())[_fastCls._NSGString
-	    instanceMethodForSelector: @selector(hash)];
+  _fastImp._NSString_isEqualToString_ = (BOOL (*)())[_fastCls._NSString
+	    instanceMethodForSelector: @selector(isEqualToString:)];
   _fastImp._NSGString_isEqual_ = (BOOL (*)())[_fastCls._NSGString
 	    instanceMethodForSelector: @selector(isEqual:)];
   _fastImp._NSGCString_isEqual_ = (BOOL (*)())[_fastCls._NSGCString

Source/NSString.m

@@ -66,6 +66,9 @@
 #include <gnustep/base/NSGString.h>
 #include <gnustep/base/NSGCString.h>
 
+#include <gnustep/base/fast.x>
+
+
 // Uncomment when implemented
     static NSStringEncoding _availableEncodings[] = {
  NSASCIIStringEncoding,
@@ -1406,11 +1409,19 @@ else
 
 - (BOOL) isEqual: (id)anObject
 {
-  if (anObject == self)
-    return YES;
-  if ([anObject isKindOfClass:[NSString class]] == YES)
-    return [self isEqualToString:anObject];
-  return NO;
+    if (anObject == self) {
+	return YES;
+    }
+    if (anObject != nil) {
+	Class c = fastClassOfInstance(anObject);
+
+	if (c != nil) {
+	    if (fastClassIsKindOfClass(c, _fastCls._NSString)) {
+		return [self isEqualToString: anObject];
+	    }
+	}
+    }
+    return NO;
 }
 
 - (BOOL) isEqualToString: (NSString*)aString
@@ -1572,7 +1583,7 @@ else
 
   /*
    *	The hash caching in our concrete strin classes uses zero to denote
-   *	an empty cache value, so we must not return a hash of zero.
+   *	an empty cache value, so we MUST NOT return a hash of zero.
    */
   if (ret == 0)
     ret = 0xffffffff;
@@ -2640,12 +2651,13 @@ else
 
 - (void) encodeWithCoder: anEncoder
 {
-  [super encodeWithCoder:anEncoder];
+    [self subclassResponsibility:_cmd];
 }
 
 - initWithCoder: aDecoder
 {
-  return [super initWithCoder:aDecoder];
+    [self subclassResponsibility:_cmd];
+    return self;
 }
 
 @end