Remove redundant variable from tree-call-cdce.c

shrink_wrap_one_built_in_call had both guard_bb and guard_bb0.
It looks like an earlier version of the pass may have updated
one of the variables in the while loop, but now they're just
two names for the same thing.

Tested on x86_64-linux-gnu, aarch64-linux-gnu and arm-linux-gnueabi.

gcc/
	* tree-call-cdce.c (shrink_wrap_one_built_in_call): Remove
	guard_bb0 and use guard_bb throughout.

From-SVN: r229532

gcc/ChangeLog

 2015-10-29  Richard Sandiford  <richard.sandiford@arm.com>
 
 	* tree-call-cdce.c (shrink_wrap_one_built_in_call): Remove
+	guard_bb0 and use guard_bb throughout.
+
+2015-10-29  Richard Sandiford  <richard.sandiford@arm.com>
+
+	* tree-call-cdce.c (shrink_wrap_one_built_in_call): Remove
 	unnecessary label.
 
 2015-10-29  Richard Biener  <rguenther@suse.de>

gcc/tree-call-cdce.c

@@ -717,7 +717,7 @@ static bool
 shrink_wrap_one_built_in_call (gcall *bi_call)
 {
   gimple_stmt_iterator bi_call_bsi;
-  basic_block bi_call_bb, join_tgt_bb, guard_bb, guard_bb0;
+  basic_block bi_call_bb, join_tgt_bb, guard_bb;
   edge join_tgt_in_edge_from_call, join_tgt_in_edge_fall_thru;
   edge bi_call_in_edge0, guard_bb_in_edge;
   unsigned tn_cond_stmts, nconds;
@@ -775,22 +775,21 @@ shrink_wrap_one_built_in_call (gcall *bi_call)
   bi_call_in_edge0 = split_block (bi_call_bb, cond_expr);
   bi_call_in_edge0->flags &= ~EDGE_FALLTHRU;
   bi_call_in_edge0->flags |= EDGE_TRUE_VALUE;
-  guard_bb0 = bi_call_bb;
+  guard_bb = bi_call_bb;
   bi_call_bb = bi_call_in_edge0->dest;
-  join_tgt_in_edge_fall_thru = make_edge (guard_bb0, join_tgt_bb,
+  join_tgt_in_edge_fall_thru = make_edge (guard_bb, join_tgt_bb,
                                           EDGE_FALSE_VALUE);
 
   bi_call_in_edge0->probability = REG_BR_PROB_BASE * ERR_PROB;
   bi_call_in_edge0->count =
-      apply_probability (guard_bb0->count,
+      apply_probability (guard_bb->count,
 			 bi_call_in_edge0->probability);
   join_tgt_in_edge_fall_thru->probability =
       inverse_probability (bi_call_in_edge0->probability);
   join_tgt_in_edge_fall_thru->count =
-      guard_bb0->count - bi_call_in_edge0->count;
+      guard_bb->count - bi_call_in_edge0->count;
 
   /* Code generation for the rest of the conditions  */
-  guard_bb = guard_bb0;
   while (nconds > 0)
     {
       unsigned ci0;