两条CPPR命令求助

fuyou_never

如题：
timing_cppr_skip_clock_reconvergence
     {true | false}
Default: false
Specifies the branch point to use for computing clock path pessimism removal (CPPR) adjustment when there is reconvergence in the clock tree.
When set to false , the software uses the branch point closest to the register clock pins where the clocks reconverge. When set to true , the software uses the farthest branch point from the register clock pins (that is, the branch point closest to the clock root pin where the clocks diverge).
To set this global variable, use the  set_global command.





timing_cppr_threshold_ps float


Default : 20 ps

Specifies the maximum amount of pessimism that clock path pessimism removal (CPPR) analysis is allowed to leave in the path. The unit is pico seconds. Setting this global to a specified value means that all the paths might be reported without having their pessimism removed. This global can be used to speed up CPPR analysis run time. The larger the value of the global, the faster the run time.

To set this global variable, use the set_global command

第一个命令是用来处理CLK信号分开在汇聚的情况吗？对于false和true具体怎么处理的？第二个是只留下所设定的（float 比如20ps）的悲观量？此外如何理解加速CPPR analysis的？ 谢谢！