Jiufu Guo <guoji...@linux.ibm.com> writes: Gentle ping. https://gcc.gnu.org/legacy-ml/gcc-patches/2020-02/msg00927.html
BR, Jiufu Guo > Jiufu Guo via Gcc-patches <gcc-patches@gcc.gnu.org> writes: > > Hi, > > I would like to reping this, hope to get approval for this patch. > https://gcc.gnu.org/legacy-ml/gcc-patches/2020-02/msg00927.html > > BR, > Jiufu Guo > >> Jiufu Guo <guoji...@linux.ibm.com> writes: >> >> Hi, >> >> I'd like to ping this patch for trunk on stage 1. >> >> This patch could fix the issue on incorrect COUNT/FREQUENCES of loop >> unrolled blocks, and also could help the improve the cold/hot issue of >> the unrolled loops. >> >> patch is also at >> https://gcc.gnu.org/legacy-ml/gcc-patches/2020-02/msg00927.html >> >> Thanks, >> Jiufu >> >>> Jiufu Guo <guoji...@linux.ibm.com> writes: >>> >>> Hi! >>> >>> I'd like to ping following patch. As near end of gcc10 stage 4, it seems >>> I would ask approval for GCC11 trunk. >>> >>> Thanks, >>> Jiufu Guo >>> >>>> Hi Honza and all, >>>> >>>> I updated the patch a little as below. Bootstrap and regtest are ok >>>> on powerpc64le. >>>> >>>> Is OK for trunk? >>>> >>>> Thanks for comments. >>>> Jiufu >>>> >>>> diff --git a/gcc/cfgloopmanip.c b/gcc/cfgloopmanip.c >>>> index 727e951..ded0046 100644 >>>> --- a/gcc/cfgloopmanip.c >>>> +++ b/gcc/cfgloopmanip.c >>>> @@ -31,6 +31,7 @@ along with GCC; see the file COPYING3. If not see >>>> #include "gimplify-me.h" >>>> #include "tree-ssa-loop-manip.h" >>>> #include "dumpfile.h" >>>> +#include "cfgrtl.h" >>>> >>>> static void copy_loops_to (class loop **, int, >>>> class loop *); >>>> @@ -1258,14 +1259,30 @@ duplicate_loop_to_header_edge (class loop *loop, >>>> edge e, >>>> /* If original loop is executed COUNT_IN times, the unrolled >>>> loop will account SCALE_MAIN_DEN times. */ >>>> scale_main = count_in.probability_in (scale_main_den); >>>> + >>>> + /* If we are guessing at the number of iterations and count_in >>>> + becomes unrealistically small, reset probability. */ >>>> + if (!(count_in.reliable_p () || loop->any_estimate)) >>>> + { >>>> + profile_count new_count_in = count_in.apply_probability >>>> (scale_main); >>>> + profile_count preheader_count = loop_preheader_edge (loop)->count >>>> (); >>>> + if (new_count_in.apply_scale (1, 10) < preheader_count) >>>> + scale_main = profile_probability::likely (); >>>> + } >>>> + >>>> scale_act = scale_main * prob_pass_main; >>>> } >>>> else >>>> { >>>> + profile_count new_loop_count; >>>> profile_count preheader_count = e->count (); >>>> - for (i = 0; i < ndupl; i++) >>>> - scale_main = scale_main * scale_step[i]; >>>> scale_act = preheader_count.probability_in (count_in); >>>> + /* Compute final preheader count after peeling NDUPL copies. */ >>>> + for (i = 0; i < ndupl; i++) >>>> + preheader_count = preheader_count.apply_probability (scale_step[i]); >>>> + /* Subtract out exit(s) from peeled copies. */ >>>> + new_loop_count = count_in - (e->count () - preheader_count); >>>> + scale_main = new_loop_count.probability_in (count_in); >>>> } >>>> } >>>> >>>> @@ -1381,6 +1398,38 @@ duplicate_loop_to_header_edge (class loop *loop, >>>> edge e, >>>> scale_bbs_frequencies (new_bbs, n, scale_act); >>>> scale_act = scale_act * scale_step[j]; >>>> } >>>> + >>>> + /* Need to update PROB of exit edge and corresponding COUNT. */ >>>> + if (orig && is_latch && (!bitmap_bit_p (wont_exit, j + 1)) >>>> + && bbs_to_scale) >>>> + { >>>> + edge new_exit = new_spec_edges[SE_ORIG]; >>>> + profile_count new_count_in = new_exit->src->count; >>>> + profile_count preheader_count = loop_preheader_edge (loop)->count (); >>>> + edge e; >>>> + edge_iterator ei; >>>> + >>>> + FOR_EACH_EDGE (e, ei, new_exit->src->succs) >>>> + if (e != new_exit) >>>> + break; >>>> + >>>> + gcc_assert (e && e != new_exit); >>>> + >>>> + new_exit->probability = preheader_count.probability_in (new_count_in); >>>> + e->probability = new_exit->probability.invert (); >>>> + >>>> + profile_count new_latch_count >>>> + = new_exit->src->count.apply_probability (e->probability); >>>> + profile_count old_latch_count = e->dest->count; >>>> + >>>> + EXECUTE_IF_SET_IN_BITMAP (bbs_to_scale, 0, i, bi) >>>> + scale_bbs_frequencies_profile_count (new_bbs + i, 1, >>>> + new_latch_count, >>>> + old_latch_count); >>>> + >>>> + if (current_ir_type () != IR_GIMPLE) >>>> + update_br_prob_note (e->src); >>>> + } >>>> } >>>> free (new_bbs); >>>> free (orig_loops); >>>> diff --git a/gcc/testsuite/gcc.dg/pr68212.c >>>> b/gcc/testsuite/gcc.dg/pr68212.c >>>> new file mode 100644 >>>> index 0000000..f3b7c22 >>>> --- /dev/null >>>> +++ b/gcc/testsuite/gcc.dg/pr68212.c >>>> @@ -0,0 +1,13 @@ >>>> +/* { dg-do compile } */ >>>> +/* { dg-options "-O2 -fno-tree-vectorize -funroll-loops --param >>>> max-unroll-times=4 -fdump-rtl-alignments" } */ >>>> + >>>> +void foo(long int *a, long int *b, long int n) >>>> +{ >>>> + long int i; >>>> + >>>> + for (i = 0; i < n; i++) >>>> + a[i] = *b; >>>> +} >>>> + >>>> +/* { dg-final { scan-rtl-dump-times "internal loop alignment added" 1 >>>> "alignments"} } */ >>>> +
