[tree-ssa] Mainline merge plan (IA64 bootstrap)

[Steve Ellcey]

> I did an update and bootstrap today, and it did fail.  I tracked it down
> to a problem in global.c.  The list of registers to allocate had two of
> them swapped.  This is presumably a problem with allocno_compare, which
> does some FP arithmetic.  I see Steve Ellcey checked in a patch which
> enabled inline FP divides by default.  If I disable that (by changing
> TARGET_DEFAULT), then the bootstrap succeeds.

Andreas Schwab found this over the weekend.  I have one proposed fix for
it that I sent in
http://gcc.gnu.org/ml/gcc-patches/2004-03/msg00065.html that I think
works but my testing isn't conclusive because any little tweek to the
build/test process seems to affect whether or not the bug appears.

Steve Ellcey
sje@cup.hp.com