Merge branch 'kvc-caching' into kvo-kvc-test

Headers/Foundation/NSGeometry.h

@@ -56,8 +56,8 @@ extern "C" {
   CGFloat y;
 }</example>
  <p>Represents a 2-d cartesian position.</p> */
-typedef struct _NSPoint NSPoint;
-struct _NSPoint
+typedef struct CGPoint NSPoint;
+struct CGPoint
 {
   CGFloat x;
   CGFloat y;
@@ -76,8 +76,8 @@ typedef NSPoint *NSPointPointer;
   CGFloat height;
 }</example>
  <p>Floating point rectangle size.</p> */
-typedef struct _NSSize NSSize;
-struct _NSSize
+typedef struct CGSize NSSize;
+struct CGSize
 {
   CGFloat width;
   CGFloat height;
@@ -97,8 +97,8 @@ typedef NSSize *NSSizePointer;
 }</example>
 
  <p>Rectangle.</p> */
-typedef struct _NSRect NSRect;
-struct _NSRect
+typedef struct CGRect NSRect;
+struct CGRect
 {
   NSPoint origin;
   NSSize size;

Source/Additions/GSObjCRuntime.m

@@ -48,6 +48,7 @@
 
 #import "../GSPrivate.h"
 #import "../GSPThread.h"
+#import "../typeEncodingHelper.h"
 
 #include <objc/Protocol.h>
 
@@ -1317,7 +1318,8 @@ unsigned long long	(*imp)(id, SEL) =
             break;
 
           case _C_STRUCT_B:
-            if (GSSelectorTypesMatch(@encode(NSPoint), type))
+		  {
+            if (IS_CGPOINT_ENCODING(type))
               {
                 NSPoint	v;
 
@@ -1334,7 +1336,7 @@ unsigned long long	(*imp)(id, SEL) =
                   }
                 val = [NSValue valueWithPoint: v];
               }
-            else if (GSSelectorTypesMatch(@encode(NSRange), type))
+            else if (IS_NSRANGE_ENCODING(type))
               {
                 NSRange	v;
 
@@ -1351,7 +1353,7 @@ unsigned long long	(*imp)(id, SEL) =
                   }
                 val = [NSValue valueWithRange: v];
               }
-            else if (GSSelectorTypesMatch(@encode(NSRect), type))
+            else if (IS_CGRECT_ENCODING(type))
               {
                 NSRect	v;
 
@@ -1368,7 +1370,7 @@ unsigned long long	(*imp)(id, SEL) =
                   }
                 val = [NSValue valueWithRect: v];
               }
-            else if (GSSelectorTypesMatch(@encode(NSSize), type))
+            else if (IS_CGSIZE_ENCODING(type))
               {
                 NSSize	v;
 
@@ -1410,6 +1412,7 @@ unsigned long long	(*imp)(id, SEL) =
                   }
               }
             break;
+		  }
 
 	  default:
 #ifdef __GNUSTEP_RUNTIME__

Source/GNUmakefile

@@ -371,6 +371,11 @@ else
 endif
 
 
+ifeq ($(OBJC_RUNTIME_LIB), ng)
+  BASE_MFILES += \
+  NSKeyValueCoding+Caching.m
+endif
+
 ifneq ($(GNUSTEP_TARGET_OS), mingw32)
   ifneq ($(GNUSTEP_TARGET_OS), mingw64)
     ifneq ($(GNUSTEP_TARGET_OS), windows)

Source/NSKeyValueCoding+Caching.h

@@ -0,0 +1,55 @@
+/** Key-Value Coding Safe Caching Support
+   Copyright (C) 2024 Free Software Foundation, Inc.
+
+   Written by:  Hugo Melder <[email protected]>
+   Created: August 2024
+
+   This file is part of the GNUstep Base Library.
+
+   This library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2 of the License, or (at your option) any later version.
+
+   This library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with this library; if not, write to the Free
+   Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110 USA.
+*/
+
+/**
+ * It turns out that valueForKey: is a very expensive operation, and a major
+ * bottleneck for Key-Value Observing and other operations such as sorting
+ * an array by key.
+ *
+ * The accessor search patterns for Key-Value observing are discussed in the
+ * Apple Key-Value Coding Programming Guide. The return value may be
+ * encapuslated into an NSNumber or NSValue object, depending on the Objective-C
+ * type encoding of the return value. This means that once valueForKey: found an
+ * existing accessor, the Objective-C type encoding of the accessor is
+ * retrieved. We then go through a huge switch case to determine the right way
+ * to invoke the IMP and potentially encapsulate the return type. The resulting
+ * object is then returned.
+ * The algorithm for setValue:ForKey: is similar.
+ *
+ * We can speed this up by caching the IMP of the accessor in a hash table.
+ * However, without proper versioning, this quickly becomes very dangerous.
+ * The user might exchange implementations, or add new ones expecting the
+ * search pattern invariant to still hold. If we clamp onto an IMP, this
+ * invariant no longer holds.
+ *
+ * We will make use of libobjc2's safe caching to avoid this.
+ *
+ * Note that the caching is opaque. You will only need to redirect all
+ * valueForKey: calls to the function below.
+ */
+
+#import "Foundation/NSString.h"
+
+id
+valueForKeyWithCaching(id obj, NSString *aKey);