[Bug target/63501] ICE in GCC powerpc64le top of trunk with -mupper-regs-df

[meissner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63501

--- Comment #3 from Michael Meissner <meissner at gcc dot gnu.org> ---
The -mupper-regs-df and -mupper-regs-sf options are a work in progress.  I am
working on these options right now on a private branch, but the code is not yet
ready for incorporation into the tree.  I don't know how long it will take to
track down the various bugs before the patches are submitted.

As I write this, the code in my branch requires the use of the -mlra option (to
switch to the LRA register allocator), and -mlra has some issues of its own
that we are investigating.

I have two spec tests (456.hmmer and 416.gamess) that fail when the
-mupper-regs-df -mlra options are used.  Of the tests that run, 454.calculix
and 470.lbm show about a 6-7% improvement, while 410.bwaves has a 6-7%
regression.