Re: Porting CLISP to architectures with few tag bits

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Florian Weimer asked in https://sourceforge.net/p/clisp/mailman/message/35478071/:
> What's the easiest way to port CLISP to a 64-bit architecture which
> does not have any reserved bits in pointers?  That is, you could use
> only the bits you get from aligning objects (e.g., 3 bits for 8-byte
> alignment).

Assume your platform is denoted by FOO64. You edit these lines of lispbibl.d:

#if defined(DECALPHA) || defined(MIPS64) || defined(SPARC64) || defined(IA64) || defined(AMD64) || defined(FOO64)
  #define WIDE_HARD
#endif

to include your platform. Also, edit these lines of lispbibl.d:

  #if (defined(WIDE_HARD) && !defined(UNIX_DARWIN) && !defined(FOO64)) || defined(WIDE_SOFT) || defined(MC68000) || ((alignment_long < 4) && !defined(GNU))
    #define TYPECODES
  #else
    #define HEAPCODES
  #endif

As a consequence, the following macros will be defined:
  WIDE_HARD
  HEAPCODES

Define
  #define GENERIC_64_HEAPCODES

Then look for all occurrences of LINUX_NOEXEC_HEAPCODES and create similar
definitions for GENERIC_64_HEAPCODES (very similar, just with 64-bit masks
instead of 32-bit masks).

Bruno