diff --git a/library/util_rfifo/util_rfifo_constr.sdc b/library/util_rfifo/util_rfifo_constr.sdc
new file mode 100644
index 000000000..121bac542
--- /dev/null
+++ b/library/util_rfifo/util_rfifo_constr.sdc
@@ -0,0 +1,5 @@
+
+set_false_path -from [get_registers *dout_enable*]  -to [get_registers *din_enable_m1*]
+set_false_path -from [get_registers *dout_req_t*]   -to [get_registers *din_req_t_m1*]
+set_false_path -from [get_registers *din_unf*]      -to [get_registers *dout_unf_m1*]
+
diff --git a/library/util_rfifo/util_rfifo_constr.xdc b/library/util_rfifo/util_rfifo_constr.xdc
new file mode 100644
index 000000000..cb8c395cf
--- /dev/null
+++ b/library/util_rfifo/util_rfifo_constr.xdc
@@ -0,0 +1,9 @@
+
+set_property shreg_extract no [get_cells -hier -filter {name =~ *din_enable_m*}]
+set_property shreg_extract no [get_cells -hier -filter {name =~ *din_req_t_m*}]
+set_property shreg_extract no [get_cells -hier -filter {name =~ *dout_unf_m*}]
+
+set_false_path -from [get_cells -hier -filter {name =~ *dout_enable*  && IS_SEQUENTIAL}] -to [get_cells -hier -filter {name =~ *din_enable_m1*  && IS_SEQUENTIAL}]
+set_false_path -from [get_cells -hier -filter {name =~ *dout_req_t*   && IS_SEQUENTIAL}] -to [get_cells -hier -filter {name =~ *din_req_t_m1*   && IS_SEQUENTIAL}]
+set_false_path -from [get_cells -hier -filter {name =~ *din_unf*      && IS_SEQUENTIAL}] -to [get_cells -hier -filter {name =~ *dout_unf_m1*    && IS_SEQUENTIAL}]
+