: set_input_delay and set_output_delay specify timing requirements at the block boundaries relative to a clock edge.
: Methods for specifying set_input_delay and set_output_delay to model external interface requirements. synopsys timing constraints and optimization user guide 2021
: Paths that cannot be sensitized or don't need to meet timing (e.g., asynchronous reset synchronizers). synopsys timing constraints and optimization user guide 2021
Timing closure is rarely just about speed; it is a balancing act with area and power. The 2021 release of the guide spotlights the and Fusion Compiler optimization engines. synopsys timing constraints and optimization user guide 2021
: Defining the maximum allowable rise/fall time for signals. 6. Optimization Techniques Optimization Phases