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| author | Richard Biener <rguenther@suse.de> | 2015-08-17 14:17:33 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2015-08-17 14:17:33 +0000 |
| commit | 28251e2ce19fbbe5715ac33cf4a8c349d0c95faa (patch) | |
| tree | 3436d1f599cdaa60d64cfa9b16030e7d0997e0bf | |
| parent | 6c825cd46bac36333c1970c549a8630f8c850794 (diff) | |
| download | gcc-28251e2ce19fbbe5715ac33cf4a8c349d0c95faa.zip gcc-28251e2ce19fbbe5715ac33cf4a8c349d0c95faa.tar.gz gcc-28251e2ce19fbbe5715ac33cf4a8c349d0c95faa.tar.bz2 | |
re PR tree-optimization/67221 (ICE at -Os and above on x86_64-linux-gnu: Segmentation fault (program cc1))
2015-08-17 Richard Biener <rguenther@suse.de>
PR tree-optimization/67221
* tree-ssa-sccvn.c (visit_phi): Keep all-TOP args TOP.
(sccvn_dom_walker::before_dom_children): Mark backedges of
non-executable blocks as not executable.
* gcc.dg/torture/pr67221.c: New testcase.
From-SVN: r226938
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr67221.c | 31 | ||||
| -rw-r--r-- | gcc/tree-ssa-sccvn.c | 19 |
4 files changed, 61 insertions, 1 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 76d1d07..93ec58f 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2015-08-17 Richard Biener <rguenther@suse.de> + + PR tree-optimization/67221 + * tree-ssa-sccvn.c (visit_phi): Keep all-TOP args TOP. + (sccvn_dom_walker::before_dom_children): Mark backedges of + non-executable blocks as not executable. + 2015-08-17 David Sherwood <david.sherwood@arm.com> * config/arm/arm.c (neon_element_bits): Replace call to diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 394a42f..93aed71 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2015-08-17 Richard Biener <rguenther@suse.de> + + PR tree-optimization/67221 + * gcc.dg/torture/pr67221.c: New testcase. + 2015-08-17 Mike Stump <mikestump@comcast.net> Kyrylo Tkachov <kyrylo.tkachov@arm.com> diff --git a/gcc/testsuite/gcc.dg/torture/pr67221.c b/gcc/testsuite/gcc.dg/torture/pr67221.c new file mode 100644 index 0000000..d7d33c5 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr67221.c @@ -0,0 +1,31 @@ +/* { dg-do compile } */ + +int a, b; + +int +fn1 (int p) +{ + return 0 == 0 ? p : 0; +} + +void +fn2 () +{ + int c = 1, d[1] = { 1 }; +lbl: + for (;;) + { + int e; + c ? 0 : 0 / c; + c = 0; + if (fn1 (d[0])) + break; + for (e = 0; e < 1; e++) + for (c = 1; b;) + { + if (a) + break; + goto lbl; + } + } +} diff --git a/gcc/tree-ssa-sccvn.c b/gcc/tree-ssa-sccvn.c index a72a920..aea6acc 100644 --- a/gcc/tree-ssa-sccvn.c +++ b/gcc/tree-ssa-sccvn.c @@ -3271,6 +3271,11 @@ visit_phi (gimple phi) break; } } + + /* If none of the edges was executable or all incoming values are + undefined keep the value-number at VN_TOP. */ + if (sameval == VN_TOP) + return set_ssa_val_to (PHI_RESULT (phi), VN_TOP); /* First see if it is equivalent to a phi node in this block. We prefer this as it allows IV elimination - see PRs 66502 and 67167. */ @@ -4463,7 +4468,7 @@ sccvn_dom_walker::before_dom_children (basic_block bb) reachable |= (e->flags & EDGE_EXECUTABLE); /* If the block is not reachable all outgoing edges are not - executable. */ + executable. Neither are incoming edges with src dominated by us. */ if (!reachable) { if (dump_file && (dump_flags & TDF_DETAILS)) @@ -4472,6 +4477,18 @@ sccvn_dom_walker::before_dom_children (basic_block bb) FOR_EACH_EDGE (e, ei, bb->succs) e->flags &= ~EDGE_EXECUTABLE; + + FOR_EACH_EDGE (e, ei, bb->preds) + { + if (dominated_by_p (CDI_DOMINATORS, e->src, bb)) + { + if (dump_file && (dump_flags & TDF_DETAILS)) + fprintf (dump_file, "Marking backedge from BB %d into " + "unreachable BB %d as not executable\n", + e->src->index, bb->index); + e->flags &= ~EDGE_EXECUTABLE; + } + } return; } |