This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH] Strength reduction part 3 of 4: candidates with unknown strides


On Wed, 2012-08-08 at 15:35 -0700, Janis Johnson wrote:
> On 08/08/2012 03:27 PM, Andrew Pinski wrote:
> > On Wed, Aug 8, 2012 at 3:25 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
> >> On Wed, Aug 1, 2012 at 10:36 AM, William J. Schmidt
> >> <wschmidt@linux.vnet.ibm.com> wrote:
> >>> Greetings,
> >>>
> >>> Thanks for the review of part 2!  Here's another chunk of the SLSR code
> >>> (I feel I owe you a few beers at this point).  This performs analysis
> >>> and replacement on groups of related candidates having an SSA name
> >>> (rather than a constant) for a stride.
> >>>
> >>> This leaves only the conditional increment (CAND_PHI) case, which will
> >>> be handled in the last patch of the series.
> >>>
> >>> Bootstrapped and tested on powerpc64-unknown-linux-gnu with no new
> >>> regressions.  Ok for trunk?
> >>>
> >>> Thanks,
> >>> Bill
> >>>
> >>>
> >>> gcc:
> >>>
> >>> 2012-08-01  Bill Schmidt  <wschmidt@linux.ibm.com>
> >>>
> >>>         * gimple-ssa-strength-reduction.c (struct incr_info_d): New struct.
> >>>         (incr_vec): New static var.
> >>>         (incr_vec_len): Likewise.
> >>>         (address_arithmetic_p): Likewise.
> >>>         (stmt_cost): Remove dead assignment.
> >>>         (dump_incr_vec): New function.
> >>>         (cand_abs_increment): Likewise.
> >>>         (lazy_create_slsr_reg): Likewise.
> >>>         (incr_vec_index): Likewise.
> >>>         (count_candidates): Likewise.
> >>>         (record_increment): Likewise.
> >>>         (record_increments): Likewise.
> >>>         (unreplaced_cand_in_tree): Likewise.
> >>>         (optimize_cands_for_speed_p): Likewise.
> >>>         (lowest_cost_path): Likewise.
> >>>         (total_savings): Likewise.
> >>>         (analyze_increments): Likewise.
> >>>         (ncd_for_two_cands): Likewise.
> >>>         (nearest_common_dominator_for_cands): Likewise.
> >>>         (profitable_increment_p): Likewise.
> >>>         (insert_initializers): Likewise.
> >>>         (introduce_cast_before_cand): Likewise.
> >>>         (replace_rhs_if_not_dup): Likewise.
> >>>         (replace_one_candidate): Likewise.
> >>>         (replace_profitable_candidates): Likewise.
> >>>         (analyze_candidates_and_replace): Handle candidates with SSA-name
> >>>         strides.
> >>>
> >>> gcc/testsuite:
> >>>
> >>> 2012-08-01  Bill Schmidt  <wschmidt@linux.ibm.com>
> >>>
> >>>         * gcc.dg/tree-ssa/slsr-5.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-6.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-7.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-8.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-9.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-10.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-11.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-12.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-13.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-14.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-15.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-16.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-17.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-18.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-19.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-20.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-21.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-22.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-23.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-24.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-25.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-26.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-30.c: New.
> >>>         * gcc.dg/tree-ssa/slsr-31.c: New.
> >>>
> >>>
> >> ======================================
> >>> --- gcc/testsuite/gcc.dg/tree-ssa/slsr-30.c     (revision 0)
> >>> +++ gcc/testsuite/gcc.dg/tree-ssa/slsr-30.c     (revision 0)
> >>> @@ -0,0 +1,25 @@
> >>> +/* Verify straight-line strength reduction fails for simple integer addition
> >>> +   with casts thrown in when -fwrapv is used.  */
> >>> +
> >>> +/* { dg-do compile } */
> >>> +/* { dg-options "-O3 -fdump-tree-dom2 -fwrapv" } */
> >>> +/* { dg-skip-if "" { ilp32 } { "-m32" } { "" } } */
> >>> +
> >>
> >> This doesn't work on x32 nor Linux/ia32 since -m32
> >> may not be needed for ILP32.  This patch works for
> >> me.  OK to install?
> > 
> > This also does not work for mips64 where the options are either
> > -mabi=32 or -mabi=n32 for ILP32.
> > 
> > HJL's patch looks correct.
> > 
> > Thanks,
> > Andrew
> 
> There are GCC targets with 16-bit integers.  What's the actual
> set of targets on which this test is meant to run?  There's a list
> of effective-target names based on data type sizes in
> <http://gcc.gnu.org/onlinedocs/gccint/Effective_002dTarget-Keywords.html#Effective_002dTarget-Keywords>.

Yes, sorry.  The test really is only valid when int and long have
different sizes.  So according to that link we should skip ilp32 and
llp64 at a minimum.  It isn't clear what we should do for int16 since
the size of long isn't specified, so I suppose we should skip that as
well.  So, perhaps modify HJ's patch to have

/* { dg-do compile { target { ! { ilp32 llp64 int16 } } } } */

?

Thanks,
Bill

> 
> Janis
> 
> >>
> >> Thanks.
> >>
> >>
> >> --
> >> H.J.
> >> ---
> >>        * gcc.dg/tree-ssa/slsr-30.c: Require non-ilp32.  Remove
> >>        dg-skip-if.
> >>
> >> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/slsr-30.c b/gcc/testsuite/gcc.dg/tree
> >> -ssa/slsr-30.c
> >> index fbd6897..7921f43 100644
> >> --- a/gcc/testsuite/gcc.dg/tree-ssa/slsr-30.c
> >> +++ b/gcc/testsuite/gcc.dg/tree-ssa/slsr-30.c
> >> @@ -1,9 +1,8 @@
> >>  /* Verify straight-line strength reduction fails for simple integer addition
> >>     with casts thrown in when -fwrapv is used.  */
> >>
> >> -/* { dg-do compile } */
> >> +/* { dg-do compile { target { ! { ilp32 } } } } */
> >>  /* { dg-options "-O3 -fdump-tree-dom2 -fwrapv" } */
> >> -/* { dg-skip-if "" { ilp32 } { "-m32" } { "" } } */
> >>
> >>  long
> >>  f (int s, long c)
> > 
> 


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]