* loop.c (loop_givs_rescan): Delete the REG_EQUAL note, not the insn.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@55590 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 8 insertions, 6 deletions

diff --git a/gcc/loop.c b/gcc/loop.c
index 5966324dc34..c943c6d8905 100644
--- a/gcc/loop.c
+++ b/gcc/loop.c
@@ -4875,6 +4875,7 @@ loop_givs_rescan (loop, bl, reg_map)
       else
 	{
 	  rtx original_insn = v->insn;
+	  rtx note;
 
 	  /* Not replaceable; emit an insn to set the original giv reg from
 	     the reduced giv, same as above.  */
@@ -4882,12 +4883,13 @@ loop_givs_rescan (loop, bl, reg_map)
 					  gen_move_insn (v->dest_reg,
 							 v->new_reg));
 
-	  /* The original insn may have a REG_EQUAL note.  This note is
-	     now incorrect and may result in invalid substitutions later.
-	     We could just delete the note, but we know that the entire
-	     insn is dead, so we might as well save ourselves the bother
-	     and remove the whole thing.  */
-	  delete_insn (original_insn);
+ 	  /* The original insn may have a REG_EQUAL note.  This note is
+ 	     now incorrect and may result in invalid substitutions later.
+ 	     The original insn is dead, but may be part of a libcall
+ 	     sequence, which doesn't seem worth the bother of handling.  */
+ 	  note = find_reg_note (original_insn, REG_EQUAL, NULL_RTX);
+ 	  if (note)
+ 	    remove_note (original_insn, note);
 	}
 
       /* When a loop is reversed, givs which depend on the reversed