From 87f46a16ec05beb51439f55a4d3c36d64b95b00f Mon Sep 17 00:00:00 2001 From: Richard Biener Date: Mon, 18 Jul 2022 13:09:57 +0200 Subject: [PATCH] Fix builtin vs non-builtin partition merge in loop distribution When r7-6373-g40b6bff965d004 fixed a costing issue it failed to make the logic symmetric which means that we now fuse normal vs. builtin when the cost model says so but we don't fuse builtin vs. normal. The following fixes that, also allowing the cost model to decide to fuse two builtin partitions as otherwise an intermediate non-builtin can result in a partial merge as well. * tree-loop-distribution.cc (loop_distribution::distribute_loop): When computing cost-based merging do not disregard builtin classified partitions in some cases. * gcc.dg/tree-ssa/ldist-24.c: XFAIL. * gcc.dg/tree-ssa/ldist-36.c: Adjust expected outcome. --- gcc/testsuite/gcc.dg/tree-ssa/ldist-24.c | 5 +++-- gcc/testsuite/gcc.dg/tree-ssa/ldist-36.c | 3 ++- gcc/tree-loop-distribution.cc | 5 +---- 3 files changed, 6 insertions(+), 7 deletions(-) diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ldist-24.c b/gcc/testsuite/gcc.dg/tree-ssa/ldist-24.c index 75f7b8f0c88c..2403a24293b7 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/ldist-24.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/ldist-24.c @@ -20,5 +20,6 @@ void foo () } } -/* { dg-final { scan-tree-dump "generated memcpy" "ldist" } } */ -/* { dg-final { scan-tree-dump "generated memset zero" "ldist" } } */ +/* The cost modeling does not consider WAR as beneficial to split. */ +/* { dg-final { scan-tree-dump "generated memcpy" "ldist" { xfail *-*-* } } } */ +/* { dg-final { scan-tree-dump "generated memset zero" "ldist" { xfail *-*-* } } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ldist-36.c b/gcc/testsuite/gcc.dg/tree-ssa/ldist-36.c index 07393f0a665a..6d560060e09a 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/ldist-36.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/ldist-36.c @@ -25,4 +25,5 @@ foo (struct st * restrict p) } } -/* { dg-final { scan-tree-dump-times "Loop nest . distributed: split to 0 loops and 3 library" 1 "ldist" } } */ +/* The cost modeling doesn't consider splitting a WAR re-use profitable. */ +/* { dg-final { scan-tree-dump-times "Loop nest . distributed: split to 1 loops and 1 library" 1 "ldist" } } */ diff --git a/gcc/tree-loop-distribution.cc b/gcc/tree-loop-distribution.cc index 0714bc41a43e..0ee441c077d0 100644 --- a/gcc/tree-loop-distribution.cc +++ b/gcc/tree-loop-distribution.cc @@ -3090,10 +3090,7 @@ loop_distribution::distribute_loop (class loop *loop, for (i = 0; partitions.iterate (i, &into); ++i) { bool changed = false; - if (partition_builtin_p (into) || into->kind == PKIND_PARTIAL_MEMSET) - continue; - for (int j = i + 1; - partitions.iterate (j, &partition); ++j) + for (int j = i + 1; partitions.iterate (j, &partition); ++j) { if (share_memory_accesses (rdg, into, partition)) { -- 2.47.2