enable_ccpp_removal (::quartus::sta)
The following table displays information for the enable_ccpp_removal Tcl command:
Tcl Package and Version |
Belongs to ::quartus::sta 1.0 |
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Syntax | enable_ccpp_removal [-h | -help] [-long_help] [-depth <depth> ] [-off] [-on] | |||
Arguments | -h | -help | Short help | ||
-long_help | Long help with examples and possible return values | |||
-depth <depth> | maximum clock tree depth for cppp removal | |||
-off | Disable this setting. | |||
-on | Enable this setting. | |||
Description |
Enables (or disables) common clock path pessimism (CCPP) removal during slack computation. CCPP removal can improve timing results by removing min/max delay differences from common portions of clock paths. Enabling CCPP removal increases the time required to perform timing analysis. When specified, the optional depth parameter limits the clock tree depth used for CCPP removal. This is generally not applicable to FPGA compilations where the clock tree is fixed, but for large HardCopy designs with potentially deep synthesized clock trees this can reduce outlier run time. When not specified, or when specified with a value of 0, the complete clock tree is used for CCPP removal (i.e. full clock-tree depth). |
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Example Usage |
project_open top create_timing_netlist read_sdc # Report timing without CCPP removal report_timing # Enable CCPP removal and re-report timing. enable_ccpp_removal report_timing delete_timing_netlist project_close |
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Return Value | Code Name | Code | String Return | |
TCL_OK | 0 | INFO: Operation successful | ||
TCL_ERROR | 1 | ERROR: Timing netlist does not exist. Use create_timing_netlist to create a timing netlist. |