tree-optimization/107803 - abnormal cleanup from the SSA propagator

The SSA propagator is missing abnormal cleanup which shows in a
sanity check in the uninit engine (and missed CFG verification).
The following adds that.

	PR tree-optimization/107803
	* tree-ssa-propagate.cc (substitute_and_fold_dom_walker): Add
	need_ab_cleanup member.
	(substitute_and_fold_dom_walker::before_dom_children): When
	a stmt can no longer transfer control flow abnormally set
	need_ab_cleanup.
	(substitute_and_fold_engine::substitute_and_fold): Cleanup
	abnormal control flow.

	* g++.dg/pr107803.C: New testcase.
This commit is contained in:
Richard Biener
2022-11-22 10:16:14 +01:00
parent 0f9659e770
commit e4faee8d02
2 changed files with 37 additions and 2 deletions
+19
View File
@@ -0,0 +1,19 @@
// { dg-do compile }
// { dg-options "-O -fno-tree-dominator-opts -fno-tree-fre -Wmaybe-uninitialized" }
void printf(...);
void __sigsetjmp_cancel() __attribute__((__returns_twice__));
int z, main_ret;
void func(void *) {}
int
main()
{
int x;
void (*__cancel_routine)(void *)(func);
__sigsetjmp_cancel();
__cancel_routine(0);
if (main_ret)
x = z;
printf(x);
}
+18 -2
View File
@@ -671,12 +671,14 @@ public:
stmts_to_remove.create (0);
stmts_to_fixup.create (0);
need_eh_cleanup = BITMAP_ALLOC (NULL);
need_ab_cleanup = BITMAP_ALLOC (NULL);
}
~substitute_and_fold_dom_walker ()
{
stmts_to_remove.release ();
stmts_to_fixup.release ();
BITMAP_FREE (need_eh_cleanup);
BITMAP_FREE (need_ab_cleanup);
}
edge before_dom_children (basic_block) final override;
@@ -689,6 +691,7 @@ public:
vec<gimple *> stmts_to_remove;
vec<gimple *> stmts_to_fixup;
bitmap need_eh_cleanup;
bitmap need_ab_cleanup;
class substitute_and_fold_engine *substitute_and_fold_engine;
@@ -838,8 +841,13 @@ substitute_and_fold_dom_walker::before_dom_children (basic_block bb)
folded. */
did_replace = false;
gimple *old_stmt = stmt;
bool was_noreturn = (is_gimple_call (stmt)
&& gimple_call_noreturn_p (stmt));
bool was_noreturn = false;
bool can_make_abnormal_goto = false;
if (is_gimple_call (stmt))
{
was_noreturn = gimple_call_noreturn_p (stmt);
can_make_abnormal_goto = stmt_can_make_abnormal_goto (stmt);
}
/* Replace real uses in the statement. */
did_replace |= substitute_and_fold_engine->replace_uses_in (stmt);
@@ -905,6 +913,12 @@ substitute_and_fold_dom_walker::before_dom_children (basic_block bb)
if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt))
bitmap_set_bit (need_eh_cleanup, bb->index);
/* If we turned a call with possible abnormal control transfer
into one that doesn't, remove abnormal edges. */
if (can_make_abnormal_goto
&& !stmt_can_make_abnormal_goto (stmt))
bitmap_set_bit (need_ab_cleanup, bb->index);
/* If we turned a not noreturn call into a noreturn one
schedule it for fixup. */
if (!was_noreturn
@@ -1012,6 +1026,8 @@ substitute_and_fold_engine::substitute_and_fold (basic_block block)
if (!bitmap_empty_p (walker.need_eh_cleanup))
gimple_purge_all_dead_eh_edges (walker.need_eh_cleanup);
if (!bitmap_empty_p (walker.need_ab_cleanup))
gimple_purge_all_dead_abnormal_call_edges (walker.need_ab_cleanup);
/* Fixup stmts that became noreturn calls. This may require splitting
blocks and thus isn't possible during the dominator walk. Do this