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| author | Richard Biener <rguenther@suse.de> | 2016-01-29 11:21:19 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2016-01-29 11:21:19 +0000 |
| commit | d4abfcc561b77aa2ac7328d965b08efd1b2561b2 (patch) | |
| tree | d41c277b595780348ce12b51329c77c3442d46d6 | |
| parent | 16b77b321eb72c5e2e1ec3628c035df80bef8534 (diff) | |
| download | gcc-d4abfcc561b77aa2ac7328d965b08efd1b2561b2.zip gcc-d4abfcc561b77aa2ac7328d965b08efd1b2561b2.tar.gz gcc-d4abfcc561b77aa2ac7328d965b08efd1b2561b2.tar.bz2 | |
re PR middle-end/69547 (no-op array initializer emits an empty loop)
2016-01-29 Richard Biener <rguenther@suse.de>
PR tree-optimization/69547
* tree-ssa-dce.c (mark_aliased_reaching_defs_necessary_1):
Do not mark clobbers necessary.
(mark_all_reaching_defs_necessary_1): Likewise.
* g++.dg/tree-ssa/pr69547.C: New testcase.
From-SVN: r232976
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/tree-ssa/pr69547.C | 15 | ||||
| -rw-r--r-- | gcc/tree-ssa-dce.c | 6 |
4 files changed, 31 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 268dd61..3f5972c 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2016-01-29 Richard Biener <rguenther@suse.de> + + PR tree-optimization/69547 + * tree-ssa-dce.c (mark_aliased_reaching_defs_necessary_1): + Do not mark clobbers necessary. + (mark_all_reaching_defs_necessary_1): Likewise. + 2016-01-29 Dominik Vogt <vogt@linux.vnet.ibm.com> * config/s390/s390-c.c (s390_resolve_overloaded_builtin): Format diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index d021755..6b2ddbd 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2016-01-29 Richard Biener <rguenther@suse.de> + + PR tree-optimization/69547 + * g++.dg/tree-ssa/pr69547.C: New testcase. + 2016-01-29 Jakub Jelinek <jakub@redhat.com> PR debug/66869 diff --git a/gcc/testsuite/g++.dg/tree-ssa/pr69547.C b/gcc/testsuite/g++.dg/tree-ssa/pr69547.C new file mode 100644 index 0000000..3045234 --- /dev/null +++ b/gcc/testsuite/g++.dg/tree-ssa/pr69547.C @@ -0,0 +1,15 @@ +// { dg-do compile } +// { dg-options "-O2 -fdump-tree-cddce1" } + +struct A { A () { } }; + +void foo (void*, int); + +void bar () +{ + enum { N = 64 }; + A a [N]; + foo (&a, N); +} + +// { dg-final { scan-tree-dump-not "if" "cddce1" } } diff --git a/gcc/tree-ssa-dce.c b/gcc/tree-ssa-dce.c index 8c3dd8f..75aaee9 100644 --- a/gcc/tree-ssa-dce.c +++ b/gcc/tree-ssa-dce.c @@ -462,7 +462,8 @@ mark_aliased_reaching_defs_necessary_1 (ao_ref *ref, tree vdef, void *data) gimple *def_stmt = SSA_NAME_DEF_STMT (vdef); /* All stmts we visit are necessary. */ - mark_operand_necessary (vdef); + if (! gimple_clobber_p (def_stmt)) + mark_operand_necessary (vdef); /* If the stmt lhs kills ref, then we can stop walking. */ if (gimple_has_lhs (def_stmt) @@ -584,7 +585,8 @@ mark_all_reaching_defs_necessary_1 (ao_ref *ref ATTRIBUTE_UNUSED, } } - mark_operand_necessary (vdef); + if (! gimple_clobber_p (def_stmt)) + mark_operand_necessary (vdef); return false; } |