@@ -120,6 +120,6 @@ bool valid_gimple_call_p (tree);
void move_ssa_defining_stmt_for_defs (gimple, gimple);
bool update_call_from_tree (gimple_stmt_iterator *, tree);
bool stmt_makes_single_store (gimple);
-bool substitute_and_fold (prop_value_t *, ssa_prop_fold_stmt_fn);
+bool substitute_and_fold (prop_value_t *, ssa_prop_fold_stmt_fn, bool);
#endif /* _TREE_SSA_PROPAGATE_H */
@@ -964,10 +964,13 @@ replace_phi_args_in (gimple phi, prop_va
If FOLD_FN is non-NULL the function will be invoked on all statements
before propagating values for pass specific simplification.
+ DO_DCE is true if trivially dead stmts can be removed.
+
Return TRUE when something changed. */
bool
-substitute_and_fold (prop_value_t *prop_value, ssa_prop_fold_stmt_fn fold_fn)
+substitute_and_fold (prop_value_t *prop_value, ssa_prop_fold_stmt_fn fold_fn,
+ bool do_dce)
{
basic_block bb;
bool something_changed = false;
@@ -1012,8 +1015,12 @@ substitute_and_fold (prop_value_t *prop_
continue;
/* No point propagating into a stmt whose result is not used,
- but instead we might be able to remove a trivially dead stmt. */
- if (gimple_get_lhs (stmt)
+ but instead we might be able to remove a trivially dead stmt.
+ Don't do this when called from VRP, since the SSA_NAME which
+ is going to be released could be still referenced in VRP
+ ranges. */
+ if (do_dce
+ && gimple_get_lhs (stmt)
&& TREE_CODE (gimple_get_lhs (stmt)) == SSA_NAME
&& has_zero_uses (gimple_get_lhs (stmt))
&& !stmt_could_throw_p (stmt)
@@ -854,7 +854,7 @@ fini_copy_prop (void)
duplicate_ssa_name_ptr_info (tmp[i].value, SSA_NAME_PTR_INFO (var));
}
- substitute_and_fold (tmp, NULL);
+ substitute_and_fold (tmp, NULL, true);
free (cached_last_copy_of);
free (copy_of);
@@ -682,7 +682,7 @@ ccp_finalize (void)
do_dbg_cnt ();
/* Perform substitutions based on the known constant values. */
- something_changed = substitute_and_fold (const_val, ccp_fold_stmt);
+ something_changed = substitute_and_fold (const_val, ccp_fold_stmt, true);
free (const_val);
const_val = NULL;
@@ -7343,7 +7343,7 @@ vrp_finalize (void)
single_val_range = NULL;
}
- substitute_and_fold (single_val_range, vrp_fold_stmt);
+ substitute_and_fold (single_val_range, vrp_fold_stmt, false);
if (warn_array_bounds)
check_all_array_refs ();
@@ -1,5 +1,5 @@
/* { dg-do compile } */
-/* { dg-options "-O2 -fdump-tree-vrp1" } */
+/* { dg-options "-O2 -fdump-tree-vrp1 -fdump-tree-dce1" } */
int
foo (int *p)
@@ -16,8 +16,9 @@ foo (int *p)
}
/* Target with fno-delete-null-pointer-checks should not fold checks */
-/* { dg-final { scan-tree-dump-times "Folding predicate " 1 "vrp1" { target { ! keeps_null_pointer_checks } } } } */
+/* { dg-final { scan-tree-dump "Folding predicate " "vrp1" { target { ! keeps_null_pointer_checks } } } } */
/* { dg-final { scan-tree-dump-times "Folding predicate " 0 "vrp1" { target { keeps_null_pointer_checks } } } } */
-/* { dg-final { scan-tree-dump-not "b_. =" "vrp1" { target { ! avr-*-* } } } } */
-/* { dg-final { scan-tree-dump "b_. =" "vrp1" { target { avr-*-* } } } } */
+/* { dg-final { scan-tree-dump-not "b_. =" "dce1" { target { ! avr-*-* } } } } */
+/* { dg-final { scan-tree-dump "b_. =" "dce1" { target { avr-*-* } } } } */
/* { dg-final { cleanup-tree-dump "vrp1" } } */
+/* { dg-final { cleanup-tree-dump "dce1" } } */
Hi! libgomp.fortran/vla*.f90 fails on s390 on 4.4 branch, because substitute_and_fold DCEs some trivially dead statements after earlier substitutions/folding), which releases the LHS SSA_NAMEs. Those SSA_NAMEs are still referenced from some VRP ranges though and can result in crashes, either still in substitute_and_fold in other folding using VRP, or in subsequent identify_jump_threads call. The problem is just latent on the trunk. Bootstrapped/regtested on x86_64-linux and i686-linux on the trunk and on x86_64-linux, i686-linux and s390-linux so far on 4.4 branch. Jakub 2010-06-14 Jakub Jelinek <jakub@redhat.com> PR tree-optimization/44508 * tree-ssa-propagate.h (substitute_and_fold): Add DO_DCE argument. * tree-ssa-propagate.c (substitute_and_fold): If !DO_DCE, don't eliminate trivially dead stmts. * tree-vrp.c (vrp_finalize): Pass false as last argument to substitute_and_fold. * tree-ssa-copy.c (fini_copy_prop): Pass true as last argument to substitute_and_fold. * tree-ssa-ccp.c (ccp_finalize): Likewise. * gcc.dg/tree-ssa/pr21086.c: Adjust. 2010-06-14 Jakub Jelinek <jakub@redhat.com> PR tree-optimization/44508 * tree-ssa-propagate.c (substitute_and_fold): Don't do DCE when called from tree-vrp.c. * gcc.dg/tree-ssa/pr21086.c: Adjust. --- gcc/tree-ssa-propagate.c.jj 2009-04-24 21:41:29.000000000 +0200 +++ gcc/tree-ssa-propagate.c 2010-06-14 09:39:54.000000000 +0200 @@ -1113,8 +1113,12 @@ substitute_and_fold (prop_value_t *prop_ } /* No point propagating into a stmt whose result is not used, - but instead we might be able to remove a trivially dead stmt. */ - if (gimple_get_lhs (stmt) + but instead we might be able to remove a trivially dead stmt. + Don't do this when called from VRP, since the SSA_NAME which + is going to be released could be still referenced in VRP + ranges. */ + if (!use_ranges_p + && gimple_get_lhs (stmt) && TREE_CODE (gimple_get_lhs (stmt)) == SSA_NAME && has_zero_uses (gimple_get_lhs (stmt)) && !stmt_could_throw_p (stmt) --- gcc/testsuite/gcc.dg/tree-ssa/pr21086.c.jj 2010-06-11 11:00:43.000000000 +0200 +++ gcc/testsuite/gcc.dg/tree-ssa/pr21086.c 2010-06-14 13:14:39.354353715 +0200 @@ -1,5 +1,5 @@ /* { dg-do compile } */ -/* { dg-options "-O2 -fdump-tree-vrp1" } */ +/* { dg-options "-O2 -fdump-tree-vrp1 -fdump-tree-dce1" } */ int foo (int *p) @@ -16,8 +16,9 @@ foo (int *p) } /* Target with fno-delete-null-pointer-checks should not fold checks */ -/* { dg-final { scan-tree-dump-times "Folding predicate " 1 "vrp1" { target { ! keeps_null_pointer_checks } } } } */ +/* { dg-final { scan-tree-dump "Folding predicate " "vrp1" { target { ! keeps_null_pointer_checks } } } } */ /* { dg-final { scan-tree-dump-times "Folding predicate " 0 "vrp1" { target { keeps_null_pointer_checks } } } } */ -/* { dg-final { scan-tree-dump-not "b_. =" "vrp1" { target { ! avr-*-* } } } } */ -/* { dg-final { scan-tree-dump "b_. =" "vrp1" { target { avr-*-* } } } } */ +/* { dg-final { scan-tree-dump-not "b_. =" "dce1" { target { ! avr-*-* } } } } */ +/* { dg-final { scan-tree-dump "b_. =" "dce1" { target { avr-*-* } } } } */ /* { dg-final { cleanup-tree-dump "vrp1" } } */ +/* { dg-final { cleanup-tree-dump "dce1" } } */