From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1729) id 1B1233850237; Wed, 29 Jun 2022 14:42:48 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 1B1233850237 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Kwok Yeung To: gcc-cvs@gcc.gnu.org Subject: [gcc/devel/omp/gcc-12] graphite: Tune parameters for OpenACC use X-Act-Checkin: gcc X-Git-Author: Frederik Harwath X-Git-Refname: refs/heads/devel/omp/gcc-12 X-Git-Oldrev: d6e47d42ddcc77680029e96516f6eff1de7a144b X-Git-Newrev: cda804467466dc8e55f3e2d8e0a7f1c1ab700c52 Message-Id: <20220629144248.1B1233850237@sourceware.org> Date: Wed, 29 Jun 2022 14:42:48 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Jun 2022 14:42:48 -0000 https://gcc.gnu.org/g:cda804467466dc8e55f3e2d8e0a7f1c1ab700c52 commit cda804467466dc8e55f3e2d8e0a7f1c1ab700c52 Author: Frederik Harwath Date: Tue Nov 16 16:21:42 2021 +0100 graphite: Tune parameters for OpenACC use The default values of some parameters that restrict Graphite's resource usage are too low for many OpenACC codes. Furthermore, exceeding the limits does not alwas lead to user-visible diagnostic messages. This commit increases the parameter values on OpenACC functions. The values were chosen to allow for the analysis of all "kernels" regions in the SPEC ACCEL v1.3 benchmark suite. Warnings about exceeded Graphite-related limits are added to the -fopt-info-missed output. Those warnings are phrased in a uniform way that intentionally refers to the "data-dependence analysis" of "OpenACC loops" instead of "a failure in Graphite" to make them easier to understand for users. gcc/ChangeLog: * graphite-optimize-isl.cc (optimize_isl): Adjust param_max_isl_operations value for OpenACC functions and add special warnings if value gets exceeded. * graphite-scop-detection.cc (build_scops): Likewise for param_graphite_max_arrays_per_scop. gcc/testsuite/ChangeLog: * gcc.dg/goacc/graphite-parameter-1.c: New test. * gcc.dg/goacc/graphite-parameter-2.c: New test. Diff: --- gcc/ChangeLog.omp | 9 ++++++ gcc/graphite-optimize-isl.cc | 35 +++++++++++++++++++---- gcc/graphite-scop-detection.cc | 28 +++++++++++++++++- gcc/testsuite/ChangeLog.omp | 5 ++++ gcc/testsuite/gcc.dg/goacc/graphite-parameter-1.c | 21 ++++++++++++++ gcc/testsuite/gcc.dg/goacc/graphite-parameter-2.c | 23 +++++++++++++++ 6 files changed, 115 insertions(+), 6 deletions(-) diff --git a/gcc/ChangeLog.omp b/gcc/ChangeLog.omp index 739c1b9148a..955e3a2222f 100644 --- a/gcc/ChangeLog.omp +++ b/gcc/ChangeLog.omp @@ -1,3 +1,12 @@ +2021-11-16 Frederik Harwath + + * graphite-optimize-isl.cc (optimize_isl): Adjust + param_max_isl_operations value for OpenACC functions and add + special warnings if value gets exceeded. + + * graphite-scop-detection.cc (build_scops): Likewise for + param_graphite_max_arrays_per_scop. + 2021-11-16 Frederik Harwath * tree-ssa-pre.cc (insert): Skip any insertions in OpenACC diff --git a/gcc/graphite-optimize-isl.cc b/gcc/graphite-optimize-isl.cc index e786bd48c79..9eff4e1e22a 100644 --- a/gcc/graphite-optimize-isl.cc +++ b/gcc/graphite-optimize-isl.cc @@ -38,6 +38,7 @@ along with GCC; see the file COPYING3. If not see #include "dumpfile.h" #include "tree-vectorizer.h" #include "graphite.h" +#include "graphite-oacc.h" /* get_schedule_for_node_st - Improve schedule for the schedule node. @@ -115,6 +116,14 @@ optimize_isl (scop_p scop, bool oacc_enabled_graphite) int old_err = isl_options_get_on_error (scop->isl_context); int old_max_operations = isl_ctx_get_max_operations (scop->isl_context); int max_operations = param_max_isl_operations; + + /* The default value for param_max_isl_operations is easily exceeded + by "kernels" loops in existing OpenACC codes. Raise the values + significantly since analyzing those loops is crucial. */ + if (param_max_isl_operations == 350000 /* default value */ + && oacc_function_p (cfun)) + max_operations = 2000000; + if (max_operations) isl_ctx_set_max_operations (scop->isl_context, max_operations); isl_options_set_on_error (scop->isl_context, ISL_ON_ERROR_CONTINUE); @@ -164,11 +173,27 @@ optimize_isl (scop_p scop, bool oacc_enabled_graphite) dump_user_location_t loc = find_loop_location (scop->scop_info->region.entry->dest->loop_father); if (isl_ctx_last_error (scop->isl_context) == isl_error_quota) - dump_printf_loc (MSG_MISSED_OPTIMIZATION, loc, - "loop nest not optimized, optimization timed out " - "after %d operations [--param max-isl-operations]\n", - max_operations); - else + { + if (oacc_function_p (cfun)) + { + /* Special casing for OpenACC to unify diagnostic messages + here and in graphite-scop-detection.c. */ + dump_printf_loc (MSG_MISSED_OPTIMIZATION, loc, + "data-dependence analysis of OpenACC loop " + "nest " + "failed; try increasing the value of " + "--param=" + "max-isl-operations=%d.\n", + max_operations); + } + else + dump_printf_loc (MSG_MISSED_OPTIMIZATION, loc, + "loop nest not optimized, optimization timed " + "out after %d operations [--param " + "max-isl-operations]\n", + max_operations); + } + else dump_printf_loc (MSG_MISSED_OPTIMIZATION, loc, "loop nest not optimized, ISL signalled an error\n"); } diff --git a/gcc/graphite-scop-detection.cc b/gcc/graphite-scop-detection.cc index 4b1d330bdb4..8656e4b1e99 100644 --- a/gcc/graphite-scop-detection.cc +++ b/gcc/graphite-scop-detection.cc @@ -2053,6 +2053,9 @@ determine_openacc_reductions (scop_p scop) } } + +extern dump_user_location_t find_loop_location (class loop *); + /* Find Static Control Parts (SCoP) in the current function and pushes them to SCOPS. */ @@ -2106,6 +2109,11 @@ build_scops (vec *scops) } unsigned max_arrays = param_graphite_max_arrays_per_scop; + + if (oacc_function_p (cfun) + && param_graphite_max_arrays_per_scop == 100 /* default value */) + max_arrays = 200; + if (max_arrays > 0 && scop->drs.length () >= max_arrays) { @@ -2113,7 +2121,16 @@ build_scops (vec *scops) << scop->drs.length () << " is larger than --param graphite-max-arrays-per-scop=" << max_arrays << ".\n"); - free_scop (scop); + + if (dump_enabled_p () && oacc_function_p (cfun)) + dump_printf_loc (MSG_MISSED_OPTIMIZATION, + find_loop_location (s->entry->dest->loop_father), + "data-dependence analysis of OpenACC loop nest " + "failed; try increasing the value of --param=" + "graphite-max-arrays-per-scop=%d.\n", + max_arrays); + + free_scop (scop); continue; } @@ -2126,6 +2143,15 @@ build_scops (vec *scops) << scop_nb_params (scop) << " larger than --param graphite-max-nb-scop-params=" << max_dim << ".\n"); + + if (dump_enabled_p () && oacc_function_p (cfun)) + dump_printf_loc (MSG_MISSED_OPTIMIZATION, + find_loop_location (s->entry->dest->loop_father), + "data-dependence analysis of OpenACC loop nest " + "failed; try increasing the value of --param=" + "graphite-max-nb-scop-params=%d.\n", + max_dim); + free_scop (scop); continue; } diff --git a/gcc/testsuite/ChangeLog.omp b/gcc/testsuite/ChangeLog.omp index c78e6cc2a1d..a3553fc5504 100644 --- a/gcc/testsuite/ChangeLog.omp +++ b/gcc/testsuite/ChangeLog.omp @@ -1,3 +1,8 @@ +2021-11-16 Frederik Harwath + + * gcc.dg/goacc/graphite-parameter-1.c: New test. + * gcc.dg/goacc/graphite-parameter-2.c: New test. + 2021-11-16 Andrew Stubbs Thomas Schwinge diff --git a/gcc/testsuite/gcc.dg/goacc/graphite-parameter-1.c b/gcc/testsuite/gcc.dg/goacc/graphite-parameter-1.c new file mode 100644 index 00000000000..45adbb3f0e8 --- /dev/null +++ b/gcc/testsuite/gcc.dg/goacc/graphite-parameter-1.c @@ -0,0 +1,21 @@ +/* Verify that a warning about an exceeded Graphite parameter gets + output as optimization information and not only as a dump message + for OpenACC functions. */ + +/* { dg-additional-options "-O2 -fopt-info-missed --param=graphite-max-arrays-per-scop=1" } */ + +extern int a[1000]; +extern int b[1000]; + +void test () +{ +#pragma acc parallel loop auto +/* { dg-missed {data-dependence analysis of OpenACC loop nest failed\; try increasing the value of --param=graphite-max-arrays-per-scop=1.} "" { target *-*-* } .-1 } */ +/* { dg-missed {'auto' loop has not been analyzed \(cf. 'graphite' dumps for more information\).} "" { target *-*-* } .-2 } */ +/* { dg-missed {.*not inlinable.*} "" { target *-*-* } .-3 } */ + for (int i = 1; i < 995; i++) + a[i] = b[i + 5] + b[i - 1]; +} + + +/* { dg-prune-output ".*not inlinable.*"} */ diff --git a/gcc/testsuite/gcc.dg/goacc/graphite-parameter-2.c b/gcc/testsuite/gcc.dg/goacc/graphite-parameter-2.c new file mode 100644 index 00000000000..f2830cd62db --- /dev/null +++ b/gcc/testsuite/gcc.dg/goacc/graphite-parameter-2.c @@ -0,0 +1,23 @@ +/* Verify that a warning about an exceeded Graphite parameter gets + output as optimization information and not only as a dump message + for OpenACC functions. */ + +/* { dg-additional-options "-O2 -fopt-info-missed --param=max-isl-operations=1" } */ + +void test (int* restrict a, int *restrict b) +{ + int i = 1; + int j = 1; + int m = 0; + +#pragma acc parallel loop auto copyin(b) copyout(a) reduction(max:m) +/* { dg-missed {data-dependence analysis of OpenACC loop nest failed; try increasing the value of --param=max-isl-operations=1.} "" { target *-*-* } .-1 } */ +/* { dg-missed {'auto' loop has not been analyzed \(cf. 'graphite' dumps for more information\).} "" { target *-*-* } .-2 } */ +/* { dg-missed {.*not inlinable.*} "" { target *-*-* } .-3 } */ + for (i = 1; i < 995; i++) + { + int x = b[i] * 2; + for (j = 1; j < 995; j++) + m = m + a[i] + x; + } +}