Time of day time of day time shows the current time

Time of day TIME OF DAY time Shows the current time.
Total negative
slack
TOTAL NEG SLACK tns Shows the total negative slack of
the design.

Chapter 12: Analyzing and Resolving Design Problems
Analyzing Design Problems 12-10
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Saving Intermediate Design Databases
Design Compiler provides the capability to output an intermediate design database during
the trials phase of the optimization process. This capability is called checkpointing.
Checkpointing saves the entire hierarchy of the intermediate design. You can use this
intermediate design to debug design problems, as described in “Analyzing Design
Problems” on page 12-10 . To checkpoint automatically between each phase of compile, set
the
compile_checkpoint_phases
variable to true.
Analyzing Design Problems
Table 12-2 shows the design analysis commands provided by Design Compiler. For
additional information about these commands, see the man pages.
Trials TRIALS trials Tracks the number of
transformations that the
optimizer tried before making the
current selection.
Worst negative
slack
WORST NEG SLACK wns Shows the worst negative slack
of the current path group.
Table 12-2 Commands to Analyze Design Objects
Object Command Description
Design
report_design
report_area
report_hierarchy
report_resources
Reports design characteristics.
Reports design size and object counts.
Reports design hierarchy.
Reports resource implementations.
Instances
report_cell
Displays information about instances.
References
report_reference
Displays information about references.
Pins
report_transitive_fanin
report_transitive_fanout
Reports fanin logic.
Reports fanout logic.
Table 12-1 Compile Log Format Keywords (Continued)
Column Column header Keyword Column description

Chapter 12: Analyzing and Resolving Design Problems
Analyzing Area 12-11
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Analyzing Area
Use the
report_area
command to display area information and statistics for the current
design or instance. The command reports combinational, non-combinational, and total area.
If you have set the current instance, the report is generated for the design of that instance;
otherwise, the report is generated for the current design. Use the
-hierarchy
option to
report area used by cells across the hierarchy.
Example 12-6 shows a report generated by the
report_area
command:
Example 12-6 report_area Report Example
dc_shell > report_area
****************************************
Report : area
Design : TEST_TOP
Version: E-2010.12
Date : Sun Oct 24 02:08:37 2010
****************************************
Library(s) Used:
test_lib (File: test_lib.db)
Number of ports: 565
Number of nets: 9654
Number of cells: 8120
Number of combinational cells: 6594
Number of sequential cells: 1526
Number of macros: 0
Number of buf/inv: 1439
Number of references: 163
Ports
report_port
report_bus
report_transitive_fanin
report_transitive_fanout
Displays information about ports.