Remove unnecessary temporary in tree-if-conv.c

The call to ifc_temp_var in predicate_mem_writes become redundant
in r230099.  Before that point the mask was calculated using
fold_build_*s, but now it's calculated by gimple_build and so
is already a valid gimple value.

As it stands, the call forces an SSA_NAME-to-SSA_NAME copy
to be created, whereas SLP expects that such redundant copies
have already been eliminated.

2018-01-13  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	* tree-if-conv.c (predicate_mem_writes): Remove redundant
	call to ifc_temp_var.

From-SVN: r256638

gcc/ChangeLog

 2018-01-13  Richard Sandiford  <richard.sandiford@linaro.org>
+
+	* tree-if-conv.c (predicate_mem_writes): Remove redundant
+	call to ifc_temp_var.
+
+2018-01-13  Richard Sandiford  <richard.sandiford@linaro.org>
 	    Alan Hayward  <alan.hayward@arm.com>
 	    David Sherwood  <david.sherwood@arm.com>
 

gcc/tree-if-conv.c

@@ -2261,7 +2261,6 @@ predicate_mem_writes (loop_p loop)
 		    }
 		  gsi_insert_seq_before (&gsi, stmts, GSI_SAME_STMT);
 
-		  mask = ifc_temp_var (TREE_TYPE (mask), mask, &gsi);
 		  /* Save mask and its size for further use.  */
 		  vect_sizes.safe_push (bitsize);
 		  vect_masks.safe_push (mask);