The following adjusts release_ssa_name to not clear TREE_TYPE but set
it to error_mark_node instead. This avoids ICEs when dumping stmts
with released SSA names which can easily happen when doing -details
dumps and blocks being removed during the PRE-order CFG cleanup
phase which runs before SSA updating.
It also removes restoring SSA_NAME_VAR in exchange. Not sure
what that new incremental SSA update code was - the code is
this way since forever, we now handle anonymous SSA names
with NULL SSA_NAME_VAR just fine and SSA_NAME_VAR is set
at allocation time (plus we delay releasing when a name is
registered for update).
Bootstrap & regtest running on x86_64-unknown-linux-gnu.
Richard.
2019-03-18 Richard Biener <rguent...@suse.de>
PR middle-end/88945
* tree-ssanames.c (release_ssa_name_fn): For released SSA names
use a TREE_TYPE of error_mark_node to avoid ICEs when dumping
basic-blocks that are removed. Remove restoring SSA_NAME_VAR.
Index: gcc/tree-ssanames.c
===================================================================
--- gcc/tree-ssanames.c (revision 269754)
+++ gcc/tree-ssanames.c (working copy)
@@ -595,7 +595,6 @@ release_ssa_name_fn (struct function *fn
defining statement. */
if (! SSA_NAME_IN_FREE_LIST (var))
{
- tree saved_ssa_name_var = SSA_NAME_VAR (var);
int saved_ssa_name_version = SSA_NAME_VERSION (var);
use_operand_p imm = &(SSA_NAME_IMM_USE_NODE (var));
@@ -621,13 +620,14 @@ release_ssa_name_fn (struct function *fn
/* Restore the version number. */
SSA_NAME_VERSION (var) = saved_ssa_name_version;
- /* Hopefully this can go away once we have the new incremental
- SSA updating code installed. */
- SET_SSA_NAME_VAR_OR_IDENTIFIER (var, saved_ssa_name_var);
-
/* Note this SSA_NAME is now in the first list. */
SSA_NAME_IN_FREE_LIST (var) = 1;
+ /* Put in a non-NULL TREE_TYPE so dumping code will not ICE
+ if it happens to come along a released SSA name and tries
+ to inspect its type. */
+ TREE_TYPE (var) = error_mark_node;
+
/* And finally queue it so that it will be put on the free list. */
vec_safe_push (FREE_SSANAMES_QUEUE (fn), var);
}
