[57/77] Use scalar_int_mode in expand_expr_addr_expr

This patch rewrites the condition:

  if (tmode != address_mode && tmode != pointer_mode)
    tmode = address_mode;

to the equivalent:

  tmode == pointer_mode ? pointer_mode : address_mode

The latter has the advantage that the result is naturally
a scalar_int_mode; a later mechanical patch makes it one.

2017-08-30  Richard Sandiford  <richard.sandiford@linaro.org>
	    Alan Hayward  <alan.hayward@arm.com>
	    David Sherwood  <david.sherwood@arm.com>

gcc/
	* expr.c (expand_expr_addr_expr): Add a new_tmode local variable
	that is always either address_mode or pointer_mode.

Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>

From-SVN: r251509

gcc/ChangeLog

@@ -2,6 +2,13 @@
 	    Alan Hayward  <alan.hayward@arm.com>
 	    David Sherwood  <david.sherwood@arm.com>
 
+	* expr.c (expand_expr_addr_expr): Add a new_tmode local variable
+	that is always either address_mode or pointer_mode.
+
+2017-08-30  Richard Sandiford  <richard.sandiford@linaro.org>
+	    Alan Hayward  <alan.hayward@arm.com>
+	    David Sherwood  <david.sherwood@arm.com>
+
 	* expr.c (expand_expr_real_2): Use word_mode instead of innermode
 	when the two are known to be equal.
 

gcc/expr.c

@@ -7910,20 +7910,21 @@ expand_expr_addr_expr (tree exp, rtx target, machine_mode tmode,
   /* We can get called with some Weird Things if the user does silliness
      like "(short) &a".  In that case, convert_memory_address won't do
      the right thing, so ignore the given target mode.  */
-  if (tmode != address_mode && tmode != pointer_mode)
-    tmode = address_mode;
+  machine_mode new_tmode = (tmode == pointer_mode
+			    ? pointer_mode
+			    : address_mode);
 
   result = expand_expr_addr_expr_1 (TREE_OPERAND (exp, 0), target,
-				    tmode, modifier, as);
+				    new_tmode, modifier, as);
 
   /* Despite expand_expr claims concerning ignoring TMODE when not
      strictly convenient, stuff breaks if we don't honor it.  Note
      that combined with the above, we only do this for pointer modes.  */
   rmode = GET_MODE (result);
   if (rmode == VOIDmode)
-    rmode = tmode;
-  if (rmode != tmode)
-    result = convert_memory_address_addr_space (tmode, result, as);
+    rmode = new_tmode;
+  if (rmode != new_tmode)
+    result = convert_memory_address_addr_space (new_tmode, result, as);
 
   return result;
 }