The Esterel v5 21 System Manual - Courses

1.3. CODE GENERATION OPTIONS 7
1.3.1 Sorted Circuit Code
The default is to generate a sorted circuit code, i.e. a sorted sequence of
Boolean equations that implements the behavior of the Esterel program.
With no option, this sequence is printed out in C. This is what you got
by executing the previous command “esterel foo.strl”. This default
mode only applies to statically acyclic programs, as described in the Esterel
language primer [2]. Sorted circuit code can also be generated for cyclic constructive
programs [2, 1] using the -causal option of the Esterel command,
as in
esterel -causal prog.strl
For programs that do have static cycles, the -causal option invokes a compiling
algorithm based on Binary Decision Diagrams (BDDs), which can use
a large and somewhat unpredictable amount of space and time, see [7].
1.3.2 Interpreted Unsorted Circuit Code
One can also generate an unsorted circuit code using option -I:
esterel -I -simul foo.strl
The -I option has important advantages and drawbacks studied in Section
2.3.2. As we mentioned before, it provides better source code debugging
information. When running the xes simulation for code compiled with
option -I, a C interpreter interprets the circuit equations. The statements
executed in the current reaction appear on a green background in the sourcecode
window. This visualizes the exact execution path. We recommend to
use option -I when building a simulator with the -simul option.
1.3.3 Automaton Code
A third possibility for software code generation is to generate an automatonbased
code. This can be done in two ways. First, one can use the -A option:
esterel -A [-simul] foo.strl
The generated foo.c file is fully interchangeable with the previous ones, but
the circuit is replaced by an explicit finite-state machine transition table.
Another way to build automata is to use the former Esterel v3 technology
which is still available in Esterel v5 [3]:
esterel -v3 [-simul] foo.strl