| Message ID | 20160503145224.GP18915@bubble.grove.modra.org |
|---|---|
| State | New |
| Headers | show |
On Wed, May 04, 2016 at 12:22:24AM +0930, Alan Modra wrote: > Fixes an ICE found when using odd options. Bootstrapped and > regression tested both powerpc64-linux and powerpc64le-linux. OK to > apply? > > gcc/ > PR target/70866 > * config/rs6000/rs6000.c (rs6000_stack_info): Don't set cr_save_p > when cr2,3,4 are all fixed regs. > gcc/testsuite/ > * gcc.target/powerpc/pr70866.c: New. This one seems obvious enough (I'll have to think about your other patch). Have you tested if save and restore are correct now? I.e. not touching the fixed ones. In either case, this should improve things, please apply. Segher
On Tue, May 03, 2016 at 10:22:02AM -0500, Segher Boessenkool wrote: > Have you tested if save and restore are correct now? I.e. not touching > the fixed ones. It doesn't matter if we save more cr fields than needed, and I think the epilogue restores are good. Restores done by the unwinder won't be correct except for ELFv2, because on other ABIs we emit a single save of cr2 to .eh_frame to mean the whole cr is saved. There's not much we can do about that.
On Wed, May 04, 2016 at 09:15:20AM +0930, Alan Modra wrote: > On Tue, May 03, 2016 at 10:22:02AM -0500, Segher Boessenkool wrote: > > Have you tested if save and restore are correct now? I.e. not touching > > the fixed ones. > > It doesn't matter if we save more cr fields than needed, Right, currently we store all CR fields with movesi_from_cr, and that hinders shrink-wrapping a lot. As long as rs6000_emit_move_from_cr has the correct information (and it should anyway, for elfv2), I am happy :-) Thanks for checking, Segher
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c index 812d3bc..e94aa66 100644 --- a/gcc/config/rs6000/rs6000.c +++ b/gcc/config/rs6000/rs6000.c @@ -23702,9 +23702,9 @@ rs6000_stack_info (void) info->calls_p = (!crtl->is_leaf || cfun->machine->ra_needs_full_frame); /* Determine if we need to save the condition code registers. */ - if (df_regs_ever_live_p (CR2_REGNO) - || df_regs_ever_live_p (CR3_REGNO) - || df_regs_ever_live_p (CR4_REGNO)) + if (save_reg_p (CR2_REGNO) + || save_reg_p (CR3_REGNO) + || save_reg_p (CR4_REGNO)) { info->cr_save_p = 1; if (DEFAULT_ABI == ABI_V4) diff --git a/gcc/testsuite/gcc.target/powerpc/pr70866.c b/gcc/testsuite/gcc.target/powerpc/pr70866.c new file mode 100644 index 0000000..25fd05a --- /dev/null +++ b/gcc/testsuite/gcc.target/powerpc/pr70866.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-ffixed-cr2 -ffixed-cr3 -ffixed-cr4" } */ + +#define SET_CR(R,V) __asm__ __volatile__ ("mtcrf %0,%1" : : "n" (1<<(7-R)), "r" (V<<(4*(7-R))) : "cr" #R) + +void foo (void) +{ + SET_CR (2, 7); + SET_CR (3, 8); + SET_CR (4, 9); +}