New regressions because of ICE in flow.c

[Jan Hubicka]

> This patch appears to be causing a whole load of regressions for
> the C compiler:

It is sanity check failing.  The patch bootstrapped for me, but I see
I didn't commited and send out all the patches I had in my tree.
I am just working on it.

I apologize for the problem.

Honza
> 
> Sat Mar 30 14:08:55 CET 2002  Jan Hubicka  <jh@suse.cz>
> 
> 	* local-alloc.c (local_alloc): Avoid call of update_equiv_regs
> 	* when not optimizing.
> 
> 	* toplev.c (rest_of_compilation): Cann mark_constant_function
> 	only when optimizing.
> 
> 	* flow.c (calculate_global_regs_live): Ensure that all AUX
> 	* fields are NULL.
> 
> 	* cfgcleanup.c (bb_flags): Add BB_NONTHREADABLE_BLOCK.
> 	(thread_jump): Set BB_NONTHREADABLE_BLOCK, check it.
> 	(try_optimize_cfg): clear all AUX fields.
> 
> 	* i386.c (aligned_operand): Be prepared for SUBREGed registers.
> 	(ix86_decompose_address): Use REG_P instead of GET_CODE (...) ==
> REG.
> 	(ix86_address_cost): Be prepared for SUBREGed registers.
> 	(legitimate_address_p): Accept SUBREGed registers.
> 
> One example:
> 
> output is:
> /home/neil/src/gcc/gcc/testsuite/gcc.c-torture/compile/920409-2.c: In
> function `x':
> /home/neil/src/gcc/gcc/testsuite/gcc.c-torture/compile/920409-2.c:2:
> Internal compiler error in calculate_global_regs_live, at flow.c:1081
> Please submit a full bug report,
> with preprocessed source if appropriate.
> See <URL:http://www.gnu.org/software/gcc/bugs.html> for instructions.
> 
> Neil.