diff options
| author | Richard Guenther <rguenther@suse.de> | 2011-07-25 14:15:02 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2011-07-25 14:15:02 +0000 |
| commit | 7fdab8d4fcbcf41eb5a5cd4f529734d4a5e0d990 (patch) | |
| tree | 1b063c8799beaf1b562e98575c19404588129b96 | |
| parent | 1baae426f98fa5b03b11b097a90b79660dbb9bc2 (diff) | |
| download | gcc-7fdab8d4fcbcf41eb5a5cd4f529734d4a5e0d990.zip gcc-7fdab8d4fcbcf41eb5a5cd4f529734d4a5e0d990.tar.gz gcc-7fdab8d4fcbcf41eb5a5cd4f529734d4a5e0d990.tar.bz2 | |
re PR tree-optimization/49822 (Segfault in remove_prop_source_from_use)
2011-07-25 Richard Guenther <rguenther@suse.de>
PR tree-optimization/49822
* tree-ssa-forwprop.c (remove_prop_source_from_use): Robustify
more. Make sure to preserve stmts with side-effects. Properly
handle virtual defs, follow a longer def chain.
From-SVN: r176745
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/tree-ssa-forwprop.c | 22 |
2 files changed, 22 insertions, 7 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index c87ebd7..6543bcf 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2011-07-25 Richard Guenther <rguenther@suse.de> + + PR tree-optimization/49822 + * tree-ssa-forwprop.c (remove_prop_source_from_use): Robustify + more. Make sure to preserve stmts with side-effects. Properly + handle virtual defs, follow a longer def chain. + 2011-07-22 Romain Geissler <romain.geissler@gmail.com> PR plugins/45348 diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c index 40db928..7cf420f 100644 --- a/gcc/tree-ssa-forwprop.c +++ b/gcc/tree-ssa-forwprop.c @@ -295,9 +295,12 @@ can_propagate_from (gimple def_stmt) return true; } -/* Remove a copy chain ending in NAME along the defs. +/* Remove a chain of dead statements starting at the definition of + NAME. The chain is linked via the first operand of the defining statements. If NAME was replaced in its only use then this function can be used - to clean up dead stmts. Returns true if cleanup-cfg has to run. */ + to clean up dead stmts. The function handles already released SSA + names gracefully. + Returns true if cleanup-cfg has to run. */ static bool remove_prop_source_from_use (tree name) @@ -309,19 +312,24 @@ remove_prop_source_from_use (tree name) do { basic_block bb; - if (!has_zero_uses (name)) + if (SSA_NAME_IN_FREE_LIST (name) + || SSA_NAME_IS_DEFAULT_DEF (name) + || !has_zero_uses (name)) return cfg_changed; stmt = SSA_NAME_DEF_STMT (name); - bb = gimple_bb (stmt); - if (!bb) + if (gimple_code (stmt) == GIMPLE_PHI + || gimple_has_side_effects (stmt)) return cfg_changed; + + bb = gimple_bb (stmt); gsi = gsi_for_stmt (stmt); - release_defs (stmt); + unlink_stmt_vdef (stmt); gsi_remove (&gsi, true); + release_defs (stmt); cfg_changed |= gimple_purge_dead_eh_edges (bb); - name = (gimple_assign_copy_p (stmt)) ? gimple_assign_rhs1 (stmt) : NULL; + name = is_gimple_assign (stmt) ? gimple_assign_rhs1 (stmt) : NULL_TREE; } while (name && TREE_CODE (name) == SSA_NAME); return cfg_changed; |