Jeff Law wrote:
What purpose does changed_allocation_pseudos serve? AFAICT we
set/clear the bitmap, but never use it for anything. It was added as
part of the IRA integration. Did you have some purpose in mind for
this bitmap? If not can we just remove it?
As I remember, it was used in an optimization which was never merged
into the trunk because of its complexity and tiny impact on
performance. The optimization was to reassigning caller-used hard
registers freed by caller-save.c to spilled pseudos by IRA or reload.
Apparently my removing the optimization from IRA patch not was not
clean and the bitmap has survived.
I think we should remove it because it is not used at all. I'll submit
a patch for this. Thanks for finding this, Jeff.
