Rewrite the JDIMENSION argument management for x86 64-bit assembly to

jmorecfg.h

 /*
  * jmorecfg.h
  *
  * This file was part of the Independent JPEG Group's software:
  * Copyright (C) 1991-1997, Thomas G. Lane.
  * Modifications:
  * Copyright (C) 2009, 2011, 2014, D. R. Commander.
  * For conditions of distribution and use, see the accompanying README file.
  *
  * This file contains additional configuration options that customize the
@@ skipping 153 matching lines @@
 #ifndef XMD_H                   /* X11/xmd.h correctly defines INT32 */
 #ifndef _BASETSD_H_             /* basetsd.h correctly defines INT32 */
 typedef long INT32;
 #endif
 #endif
 
 /* Datatype used for image dimensions.  The JPEG standard only supports
  * images up to 64K*64K due to 16-bit fields in SOF markers.  Therefore
  * "unsigned int" is sufficient on all machines.  However, if you need to
  * handle larger images and you don't mind deviating from the spec, you
- * can change this datatype.
+ * can change this datatype. Note that changing this type will require
+ * potentially updating the assembly code to correctly use the new type
+ * size.
  */
 
 typedef unsigned int JDIMENSION;
 
 #define JPEG_MAX_DIMENSION  65500L  /* a tad under 64K to prevent overflows */
 
 
 /* These macros are used in all function definitions and extern declarations.
  * You could modify them if you need to change function linkage conventions;
  * in particular, you'll need to do that to make the library a Windows DLL.
@@ skipping 224 matching lines @@
 
 #ifndef FAST_FLOAT
 #ifdef HAVE_PROTOTYPES
 #define FAST_FLOAT  float
 #else
 #define FAST_FLOAT  double
 #endif
 #endif
 
 #endif /* JPEG_INTERNAL_OPTIONS */