encounter对设计加buf的方法请教

小弟在用encounter布局布线后,用它产生的网表做PT时序分析,但结果有很多时序违例. 确实hold的违例..有人提醒说是我的复位信号reset的问题,要在布局之前就对reset复位信号前加buf.............①不知道是不是这个原因才导致hold违例这么多....②还想请教一下.在reset信号前如何加buf呢?用命令还是图形界面呢?
请各位指教一下..多谢了Report : constraint
-all_violators
-path slack_only
Design : sigma
Version: C-2009.06-SP3
Date: Mon Jan 14 14:53:28 2013
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min_delay/hold ('clk' group)
EndpointSlack
-----------------------------------------------------------------
u1/b0_reg/RN-2.45(VIOLATED)
u1/b4_reg/RN-2.45(VIOLATED)
u1/b1_reg/RN-2.45(VIOLATED)
u1/b2_reg/RN-2.45(VIOLATED)
u1/b3_reg/RN-2.45(VIOLATED)
u2/b0_reg/RN-2.40(VIOLATED)
u2/b1_reg/RN-2.40(VIOLATED)
u2/b2_reg/RN-2.40(VIOLATED)
u2/b3_reg/RN-2.40(VIOLATED)
u2/b4_reg/RN-2.40(VIOLATED)
u3/b2_reg/RN-2.38(VIOLATED)
u3/b3_reg/RN-2.38(VIOLATED)
u3/b4_reg/RN-2.38(VIOLATED)
u3/b1_reg/RN-2.38(VIOLATED)
u3/b0_reg/RN-2.38(VIOLATED)
S1_reg[6]/RN-1.99(VIOLATED)
A4_reg/D-1.99(VIOLATED)
S1_reg[7]/RN-1.98(VIOLATED)
A2_reg/D-1.98(VIOLATED)
S2_reg[11]/RN-1.98(VIOLATED)
S2_reg[12]/RN-1.98(VIOLATED)
S2_reg[13]/RN-1.98(VIOLATED)
S1_reg[11]/RN-1.98(VIOLATED)
S1_reg[12]/RN-1.97(VIOLATED)
S1_reg[13]/RN-1.97(VIOLATED)
S3_reg[12]/RN-1.97(VIOLATED

Warning: Transition times on not annotated delay arcs havebeen set to zero. Cannot perform max_transition checking. (PTE-057)
max_capacitance
RequiredActual
PinCapacitanceCapacitanceSlack
-----------------------------------------------------------------
U100/Y0.160.16-0.01(VIOLATED)
U112/Y0.160.16-0.01(VIOLATED)

在RN端加buffer即可
ecoAddRepeater -cell xxx -term xxx/RN ,
这种帖子放后端板块吧

好的.多谢指点..下次一定注意.