On Mon, Mar 9, 2015 at 7:30 PM, Michael Meissner <meiss...@linux.vnet.ibm.com> wrote: > This bug was one I unfortunately introduced with the -mupper-regs support. If > the reload pass needed to reload a PLUS operation (for example, due to using > odd address with the LD/STD instructions), it would go through all of the > registers you could load DImode into, and see if it is a preferred register > class. This lead the compiler to believe it could do integer arithmetic in > the > floating point registers. > > This patch fixes the problem, by not allowing PLUS to be reloaded into FPR > registers. I have done bootstraps and make checks on both a big endian Power7 > and a little endian Power8 system, and there were no regressions. Is the > patch > ok to apply? I do not believe it needs to be back ported to GCC 4.9 since the > -mupper-regs changes are not installed currently on that branch. > > [gcc] > 2015-03-09 Michael Meissner <meiss...@linux.vnet.ibm.com> > > PR target/65242 > * config/rs6000/rs6000.c (rs6000_preferred_reload_class): Do not > allow reloads of PLUS in floating point/VSX registers. > > [gcc/testsuite] > 2015-03-09 Michael Meissner <meiss...@linux.vnet.ibm.com> > > PR target/65242 > * g++.dg/pr65242.C: New test.
This is okay. What about Jeff Law's Bugzilla comment #6 to change ?m to !m in the movdi_internal64 pattern? That also seems reasonable. Thanks, David
