go2pins: enable multithreading for backends

* Makefile,
benchs/run-benchmark.sh,
boilerplate/main.go: Here.

Makefile

@@ -24,7 +24,7 @@ all:
 	"Consider \"make release\" for a more efficient version	"
 
 release:
-	@go build -ldflags "-s -w" && go build -o ltlrec ltl/desugar/main.go 
+	@go build -ldflags "-s -w" && go build -o ltlrec ltl/desugar/main.go
 
 build-image: Dockerfile
 	docker build --no-cache -t registry.lrde.epita.fr/go2pins-debian .
@@ -39,7 +39,7 @@ check: go2pins
 	@cd tests && ./run.sh
 
 benchmark:
-	@make clean release && cd benchs && ./run-benchmark.sh
+	@make clean release && cd benchs && ./run-benchmark.sh $(nbthreads)
 
 clean:
 	go clean

benchs/run-benchmark.sh

@@ -70,10 +70,16 @@ FILES="RERS/2016-Problem10-reach.go \
        RERS/2019-Problem14-reach.go \
        RERS/2019-Problem15-reach.go "
 
-OUTPUT=benchs.csv
-OUTPUT_BB=benchs-bb.csv
-OUTPUT_REACH=benchs-reach.csv
-OUTPUT_LTL=benchs-ltl.csv
+
+NBTHREADS=1
+if [ $# -eq 1 ]; then
+    NBTHREADS=$1
+fi
+
+OUTPUT="benchs-$NBTHREADS.csv"
+OUTPUT_BB="benchs-bb-$NBTHREADS.csv"
+OUTPUT_REACH="benchs-reach-$NBTHREADS.csv"
+OUTPUT_LTL="benchs-ltl-$NBTHREADS.csv"
 
 
 echo "##################################"

boilerplate/main.go

@@ -32,6 +32,7 @@ import (
 	"os/exec"
 	"path/filepath"
 	"regexp"
+	"strconv"
 	"strings"
 	"unsafe"
 )
@@ -376,6 +377,7 @@ var (
 	kripke_ss = flag.Bool("kripke-size", false, "The size of the state space (only spot backend)")
 	list_var  = flag.Bool("list-variables", false, "Display the list of variable names.")
 	ltl       = flag.String("ltl", "", "The LTL formulae to check")
+	nb_threads = flag.Int("nb-threads", 1, "The number of threads to use")
 )
 
 func init() {
@@ -450,15 +452,28 @@ func main() {
 	if *ltl != "" {
 		var mcCmd *exec.Cmd
 		if *backend == "ltsmin" {
-			mcCmd = exec.Command(ltsmin_path(), "--threads", "1",
+			mcCmd = exec.Command(ltsmin_path(),
+				"--threads", strconv.Itoa(*nb_threads),
 				"--ltl", *ltl, maindve2C)
 		} else if *backend == "spot" || *backend == "" {
 			if !spot_dev_version() {
+				if *nb_threads != 1 {
+					panic ("This version of spot does not support multithreading")
+				}
 				mcCmd = exec.Command(spot_path(), maindve2C, "!"+*ltl)
+
 			} else {
-				mcCmd = exec.Command(spot_path(), "-e",
-					"--model", maindve2C,
-					"--formula", "!"+*ltl)
+				// Use BDD based algorithms
+				if *nb_threads == 1 {
+					mcCmd = exec.Command(spot_path(), "-e",
+						"--model", maindve2C,
+						"--formula", "!"+*ltl)
+				} else { // Use parallel algorithms
+					mcCmd = exec.Command(spot_path(), "-e",
+						"--model", maindve2C,
+						"--formula", "!"+*ltl,
+						"--parallel", strconv.Itoa(*nb_threads))
+				}
 			}
 		} else {
 			panic("backend '" + *backend + "' unknown!")