RFA: patch to solve IRA PR48336, PR48342, PR48345

[Vladimir Makarov <vmakarov at redhat dot com>]

The following patch is to solve PR48336, PR48342, PR48345.  The 
profitable hard regs exclude hard regs which are prohibited for the 
corresponding allocno mode. It is true for primary allocation and it is 
important for better colorability criteria.  Function assign_hard_reg is 
also based on this assumption.  Unfortunately, it is not true for 
secondary allocation (after IRA IR flattening or during reload).  The 
following patch solves this problem.

The patch should be very safe but I am still testing it on x86/x86-64 
bootstrap.

Is it ok to commit the patch after successful bootsrapping?

2011-03-29  Vladimir Makarov <vmakarov@redhat.com>

        PR target/48336
        PR middle-end/4834
        PR rtl-optimization/48345
        * ira-color.c (setup_conflict_profitable_regs): Exclude prohibited
        hard regs for given mode from profitable regs when doing secondary
        allocation.

Attachment: profitable-hard-regs.patch
Description: Text document