PR target/11052

* ifcvt.c (noce_process_if_block): Fail if the destination has
side-effects.

gcc.c-torture/execute/20030606-1.c: New.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@67558 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 9 insertions, 0 deletions

diff --git a/gcc/ifcvt.c b/gcc/ifcvt.c
index baac0413176..87479060784 100644
--- a/gcc/ifcvt.c
+++ b/gcc/ifcvt.c
@@ -1821,6 +1821,15 @@ noce_process_if_block (ce_info)
 	  || modified_between_p (x, PREV_INSN (if_info.cond_earliest), jump))
 	insn_b = set_b = NULL_RTX;
     }
+
+  /* If x has side effects then only the if-then-else form is safe to
+     convert.  But even in that case we would need to restore any notes
+     (such as REG_INC) at then end.  That can be tricky if 
+     noce_emit_move_insn expands to more than one insn, so disable the
+     optimization entirely for now if there are side effects.  */
+  if (side_effects_p (x))
+    return FALSE;
+
   b = (set_b ? SET_SRC (set_b) : x);
 
   /* Only operate on register destinations, and even then avoid extending