On July 27, 2017 9:10:48 PM GMT+02:00, Jakub Jelinek <ja...@redhat.com> wrote:
>Hi!
>
>Not all vectorizable reductions are valid OpenMP standard reductions
>(we could create user defined reductions from that, but that would be
>quite a lot of work).
>
>This patch bails out for unsupported reductions.
>
>Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
OK.
Thanks,
Richard.
>2017-07-27 Jakub Jelinek <ja...@redhat.com>
>
> PR tree-optimization/81578
> * tree-parloops.c (build_new_reduction): Bail out if
> reduction_code isn't one of the standard OpenMP reductions.
> Move the details printing after that decision.
>
> * gcc.dg/pr81578.c: New test.
>
>--- gcc/tree-parloops.c.jj 2017-07-19 14:01:24.000000000 +0200
>+++ gcc/tree-parloops.c 2017-07-27 14:27:13.966749227 +0200
>@@ -2475,23 +2475,39 @@ build_new_reduction (reduction_info_tabl
>
> gcc_assert (reduc_stmt);
>
>- if (dump_file && (dump_flags & TDF_DETAILS))
>- {
>- fprintf (dump_file,
>- "Detected reduction. reduction stmt is:\n");
>- print_gimple_stmt (dump_file, reduc_stmt, 0);
>- fprintf (dump_file, "\n");
>- }
>-
> if (gimple_code (reduc_stmt) == GIMPLE_PHI)
> {
> tree op1 = PHI_ARG_DEF (reduc_stmt, 0);
> gimple *def1 = SSA_NAME_DEF_STMT (op1);
> reduction_code = gimple_assign_rhs_code (def1);
> }
>-
> else
> reduction_code = gimple_assign_rhs_code (reduc_stmt);
>+ /* Check for OpenMP supported reduction. */
>+ switch (reduction_code)
>+ {
>+ case PLUS_EXPR:
>+ case MULT_EXPR:
>+ case MAX_EXPR:
>+ case MIN_EXPR:
>+ case BIT_IOR_EXPR:
>+ case BIT_XOR_EXPR:
>+ case BIT_AND_EXPR:
>+ case TRUTH_OR_EXPR:
>+ case TRUTH_XOR_EXPR:
>+ case TRUTH_AND_EXPR:
>+ break;
>+ default:
>+ return;
>+ }
>+
>+ if (dump_file && (dump_flags & TDF_DETAILS))
>+ {
>+ fprintf (dump_file,
>+ "Detected reduction. reduction stmt is:\n");
>+ print_gimple_stmt (dump_file, reduc_stmt, 0);
>+ fprintf (dump_file, "\n");
>+ }
>
> new_reduction = XCNEW (struct reduction_info);
>
>--- gcc/testsuite/gcc.dg/pr81578.c.jj 2017-07-27 14:48:16.426441581
>+0200
>+++ gcc/testsuite/gcc.dg/pr81578.c 2017-07-27 14:48:01.000000000 +0200
>@@ -0,0 +1,12 @@
>+/* PR tree-optimization/81578 */
>+/* { dg-do compile { target pthread } } */
>+/* { dg-options "-O2 -ftree-parallelize-loops=2" } */
>+
>+int
>+foo (int *x)
>+{
>+ int i, r = 1;
>+ for (i = 0; i != 1024; i++)
>+ r *= x[i] < 0;
>+ return r;
>+}
>
> Jakub
