[PATCH] tree-optimization/112827 - more SCEV cprop fixes

[Richard Biener <rguenther@suse.de>]

The insert iteration can be corrupted by foldings of replace_uses_by,
within this particular PHI replacement but also with subsequent ones.
Recompute the insert location before insertion instead.

This fixes an obvserved ICE of gcc.dg/tree-ssa/ssa-sink-16.c.

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

	PR tree-optimization/112827
	PR tree-optimization/112848
	* tree-scalar-evolution.cc (final_value_replacement_loop):
	Compute the insert location for each insert.
---
 gcc/tree-scalar-evolution.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/tree-scalar-evolution.cc b/gcc/tree-scalar-evolution.cc
index 065bcd0743d..38821ffb15a 100644
--- a/gcc/tree-scalar-evolution.cc
+++ b/gcc/tree-scalar-evolution.cc
@@ -3739,7 +3739,6 @@ final_value_replacement_loop (class loop *loop)
     split_loop_exit_edge (exit);
 
   /* Set stmt insertion pointer.  All stmts are inserted before this point.  */
-  gimple_stmt_iterator gsi = gsi_after_labels (exit->dest);
 
   class loop *ex_loop
     = superloop_at_depth (loop,
@@ -3883,6 +3882,7 @@ final_value_replacement_loop (class loop *loop)
 	      gsi_next (&gsi2);
 	    }
 	}
+      gimple_stmt_iterator gsi = gsi_after_labels (exit->dest);
       gsi_insert_seq_before (&gsi, stmts, GSI_SAME_STMT);
       if (dump_file)
 	{
-- 
2.35.3