re PR middle-end/21273 (gensupport.c:collect_insn_data doesn't consider the…

re PR middle-end/21273 (gensupport.c:collect_insn_data doesn't consider the constraints of match_scratch)

Fix PR21273

	PR middle-end/21273
	* gensupport.c (collect_insn_data): Look for number of alternatives
	in MATCH_SCRATCH.

From-SVN: r231654

gcc/ChangeLog

+2015-12-15  Bernd Schmidt  <bschmidt@redhat.com>
+
+	PR middle-end/21273
+	* gensupport.c (collect_insn_data): Look for number of alternatives
+	in MATCH_SCRATCH.
+
 2015-12-15  Nathan Sidwell  <nathan@acm.org>
 
 	* config/nvptx/nvptx.h (HARD_REGNO_NREGS): Reformat.

gcc/gensupport.c

@@ -1068,12 +1068,12 @@ collect_insn_data (rtx pattern, int *palt, int *pmax)
   switch (code)
     {
     case MATCH_OPERAND:
-      i = n_alternatives (XSTR (pattern, 2));
+    case MATCH_SCRATCH:
+      i = n_alternatives (XSTR (pattern, code == MATCH_SCRATCH ? 1 : 2));
       *palt = (i > *palt ? i : *palt);
       /* Fall through.  */
 
     case MATCH_OPERATOR:
-    case MATCH_SCRATCH:
     case MATCH_PARALLEL:
       i = XINT (pattern, 0);
       if (i > *pmax)