m68k: minor optimizations to g_proc_exit() - use LEA for stackpointer math which is better than ADDing large constants, also only modify the SP reg once

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@27817 3ad0048d-3df7-0310-abae-a5850022a9f2
* abs(): when translated to generic fpc_abs_real() helper, typecast result back to original precision, similar to how it is done for sqr and sqrt. Fixes compilation on m68k after r27808 (m86k looks like the only target still needing this generic handling).


git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@27818 3ad0048d-3df7-0310-abae-a5850022a9f2
* Updated header: this file is in cp866 encoding.

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@27819 3ad0048d-3df7-0310-abae-a5850022a9f2
+ generate the stack segment for i8086 far data memory models from within fpc
  itself (instead of having a fixed 16k stack in the startup code). This allows
  setting the stack size in these models with the -Cs option.



git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@27820 3ad0048d-3df7-0310-abae-a5850022a9f2
removed silly ancient writeln debug from me...

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@27821 3ad0048d-3df7-0310-abae-a5850022a9f2
* fixed multiplication by 64-bit constants on x86_64, mantis #26230



git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@27822 3ad0048d-3df7-0310-abae-a5850022a9f2
  + test for mantis #26226 (already works with FPC 2.7.1)

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@27823 3ad0048d-3df7-0310-abae-a5850022a9f2
* in i8086 far data memory models add reference to the beginning of stack from
  the startup code, so the object module, containing the stack segment doesn't
  get smartlinked away

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@27824 3ad0048d-3df7-0310-abae-a5850022a9f2
* put the i8086-msdos stack segment in a separate object file

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@27825 3ad0048d-3df7-0310-abae-a5850022a9f2