re PR target/66785 (internal compiler error in record_operand_use)

	PR target/66785
	* regrename.c (record_operand_use): Keep track of failed operands
	and stop appending if we see any.
	* regrename.h (struct operand_rr_info): Add a failed field and shrink
	n_chains to short.

From-SVN: r230499

gcc/ChangeLog

+2015-11-17  Bernd Schmidt  <bschmidt@redhat.com>
+
+	PR target/66785
+	* regrename.c (record_operand_use): Keep track of failed operands
+	and stop appending if we see any.
+	* regrename.h (struct operand_rr_info): Add a failed field and shrink
+	n_chains to short.
+
 2015-11-17  Sandra Loosemore  <sandra@codesourcery.com>
 
 	PR 48568

gcc/regrename.c

@@ -203,8 +203,13 @@ mark_conflict (struct du_head *chains, unsigned id)
 static void
 record_operand_use (struct du_head *head, struct du_chain *this_du)
 {
-  if (cur_operand == NULL)
+  if (cur_operand == NULL || cur_operand->failed)
     return;
+  if (head->cannot_rename)
+    {
+      cur_operand->failed = true;
+      return;
+    }
   gcc_assert (cur_operand->n_chains < MAX_REGS_PER_ADDRESS);
   cur_operand->heads[cur_operand->n_chains] = head;
   cur_operand->chains[cur_operand->n_chains++] = this_du;

gcc/regrename.h

@@ -72,7 +72,8 @@ struct du_chain
 struct operand_rr_info
 {
   /* The number of chains recorded for this operand.  */
-  int n_chains;
+  short n_chains;
+  bool failed;
   /* Holds either the chain for the operand itself, or for the registers in
      a memory operand.  */
   struct du_chain *chains[MAX_REGS_PER_ADDRESS];