[PATCH] middle-end/105083 - check prerequesites in scev_initialize

[Richard Biener via Gcc-patches]

Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.

2022-05-03  Richard Biener  <rguent...@suse.de>

        PR middle-end/105083
        * tree-scalar-evolution.cc (scev_initialize): Verify we
        have appropriate loop state.
        * tree-ssa-dce.cc (perform_tree_ssa_dce): Re-order SCEV and
        loop init and finalization.
---
 gcc/tree-scalar-evolution.cc | 3 ++-
 gcc/tree-ssa-dce.cc          | 4 ++--
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/gcc/tree-scalar-evolution.cc b/gcc/tree-scalar-evolution.cc
index b53d7aaa71d..72ceb4001e3 100644
--- a/gcc/tree-scalar-evolution.cc
+++ b/gcc/tree-scalar-evolution.cc
@@ -2977,7 +2977,8 @@ gather_stats_on_scev_database (void)
 void
 scev_initialize (void)
 {
-  gcc_assert (! scev_initialized_p ());
+  gcc_assert (! scev_initialized_p ()
+             && loops_state_satisfies_p (cfun, LOOPS_NORMAL));
 
   scalar_evolution_info = hash_table<scev_info_hasher>::create_ggc (100);
 
diff --git a/gcc/tree-ssa-dce.cc b/gcc/tree-ssa-dce.cc
index 2067b711d5b..a6b284018d4 100644
--- a/gcc/tree-ssa-dce.cc
+++ b/gcc/tree-ssa-dce.cc
@@ -1866,9 +1866,9 @@ perform_tree_ssa_dce (bool aggressive)
   bool in_loop_pipeline = scev_initialized_p ();
   if (aggressive && ! in_loop_pipeline)
     {
-      scev_initialize ();
       loop_optimizer_init (LOOPS_NORMAL
                           | LOOPS_HAVE_RECORDED_EXITS);
+      scev_initialize ();
     }
 
   if (aggressive)
@@ -1895,8 +1895,8 @@ perform_tree_ssa_dce (bool aggressive)
 
   if (aggressive && ! in_loop_pipeline)
     {
-      loop_optimizer_finalize ();
       scev_finalize ();
+      loop_optimizer_finalize ();
     }
 
   longest_chain = 0;
-- 
2.35.3