Fix va-arg-22.c at -O1 on m32r.

	PR rtl-optimization/92264
	* config/m32r/m32r.c (m32r_output_block_move): Properly account for
	post-increment addressing of source operands as well as residuals
	when computing any adjustments to the input pointer.

gcc/ChangeLog

+2020-04-03  Jeff Law  <law@redhat.com>
+
+	PR rtl-optimization/92264
+	* config/m32r/m32r.c (m32r_output_block_move): Properly account for
+	post-increment addressing of source operands as well as residuals
+	when computing any adjustments to the input pointer.
+
 2020-04-03  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/94460

gcc/config/m32r/m32r.c

@@ -2676,7 +2676,7 @@ m32r_output_block_move (rtx insn ATTRIBUTE_UNUSED, rtx operands[])
 	     destination pointer.  */
 	  int dst_inc_amount = dst_offset + bytes - 4;
 	  /* The same for the source pointer.  */
-	  int src_inc_amount = bytes;
+	  int src_inc_amount = bytes - (got_extra ? 4 : 0);
 	  int last_shift;
 	  rtx my_operands[3];