add vector exception infrastructure

rocket/src/main/scala/dpath.scala

@@ -402,6 +402,8 @@ class rocketDpath extends Component
     vec.io.vecbankcnt := pcr.io.vecbankcnt
     vec.io.wdata := wb_reg_vec_wdata
     vec.io.rs2 := wb_reg_rs2
+    vec.io.vec_eaddr := pcr.io.vec_eaddr
+    vec.io.vec_exception := pcr.io.vec_exception
 
     wb_wdata :=
       Mux(vec.io.wen, Cat(Bits(0,52), vec.io.appvl),