From 31432e219f044eb7195b9f802db88ace3e7fe8a1 Mon Sep 17 00:00:00 2001 From: Richard Guenther Date: Wed, 8 Feb 2012 15:28:01 +0000 Subject: re PR tree-optimization/46886 (wrong code with -ftree-parallelize-loops -fno-tree-ch) 2012-03-08 Richard Guenther PR tree-optimization/46886 * tree-flow.h (do_while_loop_p): Declare. * tree-ssa-loop-ch.c (do_while_loop_p): Export. * tree-parloops.c (parallelize_loops): Only parallelize do-while loops. * testsuite/libgomp.c/pr46886.c: New testcase. From-SVN: r184010 --- gcc/ChangeLog | 8 ++++++++ gcc/tree-flow.h | 3 +++ gcc/tree-parloops.c | 5 ++++- gcc/tree-ssa-loop-ch.c | 2 +- libgomp/ChangeLog | 5 +++++ libgomp/testsuite/libgomp.c/pr46886.c | 28 ++++++++++++++++++++++++++++ 6 files changed, 49 insertions(+), 2 deletions(-) create mode 100644 libgomp/testsuite/libgomp.c/pr46886.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 1c56ebe..7982452 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2012-02-08 Richard Guenther + + PR tree-optimization/46886 + * tree-flow.h (do_while_loop_p): Declare. + * tree-ssa-loop-ch.c (do_while_loop_p): Export. + * tree-parloops.c (parallelize_loops): Only parallelize do-while + loops. + 2012-02-08 Andrew MacLeod * optabs.c (expand_atomic_load): Do not assume compare_and_swap will diff --git a/gcc/tree-flow.h b/gcc/tree-flow.h index ded7a3f..f4c4d5c 100644 --- a/gcc/tree-flow.h +++ b/gcc/tree-flow.h @@ -619,6 +619,9 @@ extern bool may_propagate_copy (tree, tree); extern bool may_propagate_copy_into_stmt (gimple, tree); extern bool may_propagate_copy_into_asm (tree); +/* In tree-ssa-loop-ch.c */ +bool do_while_loop_p (struct loop *); + /* Affine iv. */ typedef struct diff --git a/gcc/tree-parloops.c b/gcc/tree-parloops.c index 28c450d..221f257 100644 --- a/gcc/tree-parloops.c +++ b/gcc/tree-parloops.c @@ -2183,7 +2183,10 @@ parallelize_loops (void) || loop_has_blocks_with_irreducible_flag (loop) || (loop_preheader_edge (loop)->src->flags & BB_IRREDUCIBLE_LOOP) /* FIXME: the check for vector phi nodes could be removed. */ - || loop_has_vector_phi_nodes (loop)) + || loop_has_vector_phi_nodes (loop) + /* FIXME: transform_to_exit_first_loop does not handle not + header-copied loops correctly - see PR46886. */ + || !do_while_loop_p (loop)) continue; estimated = max_stmt_executions_int (loop, false); /* FIXME: Bypass this check as graphite doesn't update the diff --git a/gcc/tree-ssa-loop-ch.c b/gcc/tree-ssa-loop-ch.c index 57e71b4..84e5a7d 100644 --- a/gcc/tree-ssa-loop-ch.c +++ b/gcc/tree-ssa-loop-ch.c @@ -104,7 +104,7 @@ should_duplicate_loop_header_p (basic_block header, struct loop *loop, /* Checks whether LOOP is a do-while style loop. */ -static bool +bool do_while_loop_p (struct loop *loop) { gimple stmt = last_stmt (loop->latch); diff --git a/libgomp/ChangeLog b/libgomp/ChangeLog index 8d9015d..daebf23 100644 --- a/libgomp/ChangeLog +++ b/libgomp/ChangeLog @@ -1,3 +1,8 @@ +2012-02-08 Richard Guenther + + PR tree-optimization/46886 + * testsuite/libgomp.c/pr46886.c: New testcase. + 2012-01-25 Matthias Klose * config/linux/arm: Remove empty directory. diff --git a/libgomp/testsuite/libgomp.c/pr46886.c b/libgomp/testsuite/libgomp.c/pr46886.c new file mode 100644 index 0000000..fbdc4e1 --- /dev/null +++ b/libgomp/testsuite/libgomp.c/pr46886.c @@ -0,0 +1,28 @@ +/* { dg-do run } */ +/* { dg-options "-O -ftree-parallelize-loops=4 -fno-tree-ch -fno-tree-dominator-opts" } */ + +void abort(void); + +int d[1024], e[1024]; + +int foo (void) +{ + int s = 0; + int i; + for (i = 0; i < 1024; i++) + s += d[i] - e[i]; + return s; +} + +int main () +{ + int i; + for (i = 0; i < 1024; i++) + { + d[i] = i * 2; + e[i] = i; + } + if (foo () != 1023 * 1024 / 2) + abort (); + return 0; +} -- cgit v1.1