Altera SDC and TimeQuest API - Manual (Page 71)

Chapter 2: SDC and TimeQuest API Package and Commands 2–61
sdc_ext
© December 2009 Altera Corporation SDC and TimeQuest API Reference Manual
set_scc_mode
Usage
set_scc_mode [-size <size>] [-use_heuristic]
Options
-size <size>: Maximum SCC loop size
-use_heuristic: Always use heuristic for SCC processing
Description
Allows you to set maximum Strongly Connected Components (SCC) loop size or force TimeQuest Timing
Analyzer to always estimate delays through SCCs.
When TimeQuest Timing Analyzer encounters a loop of size greater than the specified maximum SCC
loop size, it uses a heuristic which only estimates delays through the loop.
If the loop is smaller than the maximum SCC loop size, a full processing of loops is performed unless the
-use_heuristic option is used.
Example
# Make TimeQuest Timing Analyzer use normal processing for all loops
# the size of which is less than or equal to 100. For loops of size
# greater than 100, a runtime-saving heuristic will be used
set_scc_mode -size 100
# Force TimeQuest Timing Analyzer to use heuristic for all SCCs
# disregarding their size
set_scc_mode -use_heuristic