Re: Why doesn't combine like volatiles? (volatile_ok again, sorry!)

[Mike Stump <mrs@apple.com>]

On Nov 28, 2005, at 9:29 AM, Dave Korn wrote:
>   BTW, I never did manage to find the patches you referred to in  
> your postings
> from summer 2000.  Googling for "mike stump volatile_ok" just kept  
> on finding
> me the post where you were advising someone to find your patches by  
> searching
> for your name and volatile_ok.  Kinda recursive, that.... do you  
> still have a
> pointer to them?

As background for others,

http://gcc.gnu.org/ml/gcc-bugs/1999-12n/msg00801.html

has an example of why one would want to do this.

Anyway, not rocket science:

Doing diffs in .:
--- ./recog.c.~1~       2005-10-28 10:40:18.000000000 -0700
+++ ./recog.c   2005-11-28 10:10:31.000000000 -0800
@@ -956,9 +956,6 @@ general_operand (rtx op, enum machine_mo
      {
        rtx y = XEXP (op, 0);

-      if (! volatile_ok && MEM_VOLATILE_P (op))
-       return 0;
-
        /* Use the mem's mode, since it will be reloaded thus.  */
        if (memory_address_p (GET_MODE (op), y))
         return 1;
--------------

Good for testing, but a real patch would have to:

http://gcc.gnu.org/ml/gcc/2001-11/msg00398.html