Feature request concerning opcodes in the function prolog

[Stefan Dösinger]

> -----Original Message-----
> From: H.J. Lu [mailto:hjl.tools@gmail.com]
Nice to see a familiar face, or better, mail address :-)

> You need to check assembler feature with autconf before using them.
> See HAVE_AS_IX86_SAHF as example.
Thanks!

Does that look ok? It seems to detect the support correctly for me:

gcc_GAS_CHECK_FEATURE([swap suffix],
  gcc_cv_as_ix86_swap,,,
  [movl.s %esp, %ebp],,
  [AC_DEFINE(HAVE_AS_IX86_SWAP, 1,
  [Define if your assembler supports the swap suffix.])])