module,cmd: allow specifying skip function prefixes on CLI

Signed-off-by: Bohdan Trach <[email protected]>

cmd/vsyncer/info.go

@@ -53,7 +53,8 @@ func Info(fn string, args []string) error {
 
 func moduleConfig() module.Config {
 	return module.Config{
-		EntryFunc: rootFlags.entryFunc,
-		Expand:    rootFlags.expand,
+		EntryFunc:    rootFlags.entryFunc,
+		SkipFuncPref: rootFlags.skipFunc,
+		Expand:       rootFlags.expand,
 	}
 }

cmd/vsyncer/root.go

@@ -49,6 +49,7 @@ var rootCmd = cobra.Command{
 func init() {
 	tools.RegEnv("VSYNCER_DEFAULT_CHECKER", "genmc", "Default model checker")
 	tools.RegEnv("VSYNCER_DEFAULT_ENTRY_FUNC", "main", "Default entry functions for analysis")
+	tools.RegEnv("VSYNCER_DEFAULT_SKIP_FUNC", "pthread_,__assert_fail,llvm.,_VERIFIER", "Default prefixes of functions to skip")
 
 	helpMessage :=
 		`vsyncer -- Verification and optimization of concurrent code on WMM`
@@ -70,6 +71,9 @@ func init() {
 	flags.StringSliceVar(&rootFlags.entryFunc, "entry-func",
 		strings.Split(tools.GetEnv("VSYNCER_DEFAULT_ENTRY_FUNC"), ","),
 		"list of entry functions")
+	flags.StringSliceVar(&rootFlags.skipFunc, "skip-func",
+		strings.Split(tools.GetEnv("VSYNCER_DEFAULT_SKIP_FUNC"), ","),
+		"list of function prefixes to skip")
 
 	rootCmd.SetHelpCommand(&cobra.Command{Hidden: true})
 	initOptimize()

module/config.go

@@ -10,15 +10,16 @@ type Config struct {
 	Expand       bool     // whether it should expand the callgraph
 	ExpandOnly   []string // a list of function prefixes to expand
 	IdentifyOnly []string // a list of function prefixes to identify/atomify
-	IdentifySkip []string // a list of function prefixes to skip identify/atomify
+	SkipFuncPref []string // a list of function prefixes to skip identify/atomify
 	Args         []string // a list of arguments to pass to the command line of the checker
 }
 
 // DefaultConfig returns a default configuration for loading a module
 func DefaultConfig() Config {
 	return Config{
-		EntryFunc: []string{"main"},
-		Expand:    true,
+		EntryFunc:    []string{"main"},
+		SkipFuncPref: []string{"pthread_", "__assert_fail", "llvm.", "_VERIFIER"},
+		Expand:       true,
 	}
 
 }

module/history.go

@@ -31,7 +31,7 @@ type History struct {
 	}
 }
 
-// Load parses and anlyzes an LLVM IR module.
+// Load parses and analyzes an LLVM IR module.
 func Load(fn string, cfg Config) (*History, error) {
 	var efn = fn
 
@@ -43,7 +43,7 @@ func Load(fn string, cfg Config) (*History, error) {
 		}
 
 		logger.Infof("Expand '%s'", fn)
-		if err := visitModule(mod, cfg.EntryFunc, expandVisitor(mod)); err != nil {
+		if err := visitModule(mod, cfg.EntryFunc, expandVisitor(mod), cfg); err != nil {
 			return nil, err
 		}
 

module/visitor.go

@@ -28,17 +28,17 @@ type meta interface {
 // VisitCallback is called in every relevant intruction when visiting the module.
 type VisitCallback func(inst ir.Instruction, f *ir.Func, stack []meta) ir.Instruction
 
-func (w *wrapModule) Visit(fun []string, cb VisitCallback) error {
-	return visitModule(w.Module, fun, cb)
+func (w *wrapModule) Visit(fun []string, cb VisitCallback, cfg Config) error {
+	return visitModule(w.Module, fun, cb, cfg)
 }
 
-func visitModule(m *ir.Module, fun []string, cb VisitCallback) error {
+func visitModule(m *ir.Module, fun []string, cb VisitCallback, cfg Config) error {
 	for _, foo := range fun {
 		for _, f := range m.Funcs {
 			if f.Ident() != fmt.Sprintf("@%s", foo) {
 				continue
 			}
-			v := &visitor{visited: make(map[ir.Instruction]bool)}
+			v := &visitor{visited: make(map[ir.Instruction]bool), skip_prefixes: cfg.SkipFuncPref}
 			v.log("====================== START VISIT ==========================")
 			if err := v.visit(f, []meta{f}, cb); err != nil {
 				return err
@@ -49,8 +49,9 @@ func visitModule(m *ir.Module, fun []string, cb VisitCallback) error {
 }
 
 type visitor struct {
-	dep     string
-	visited map[ir.Instruction]bool
+	dep           string
+	visited       map[ir.Instruction]bool
+	skip_prefixes []string
 }
 
 func (v *visitor) enter() {
@@ -79,6 +80,16 @@ func (v *visitor) logf(str string, args ...any) {
 	logger.Print(fstr(str, args...))
 }
 
+func (v *visitor) is_callee_ignored(callee_name string) bool {
+	for _, prefix := range v.skip_prefixes {
+		// Skip "@" prefix with [1:]
+		if strings.Contains(callee_name[1:], prefix) {
+			return true
+		}
+	}
+	return false
+}
+
 func (v *visitor) visitCallee(inst *ir.InstCall, f *ir.Func, stack []meta, cb VisitCallback) error {
 	callee := inst.Callee.Ident()
 	var err error
@@ -108,9 +119,7 @@ func (v *visitor) visitCallee(inst *ir.InstCall, f *ir.Func, stack []meta, cb Vi
 		v.enter()
 		err = v.visit(ff, append(stack, inst), cb)
 		v.leave()
-	} else if !strings.Contains(callee[1:], "__assert_fail") && !strings.Contains(callee[1:], "llvm.") &&
-		!strings.Contains(callee[1:], "_VERIFIER") && !strings.Contains(callee[1:], "pthread_") {
-
+	} else if !v.is_callee_ignored(callee) {
 		switch callee := inst.Callee.(type) {
 		case *ir.InlineAsm:
 		case *ir.InstLoad:

module/wrap_module.go

@@ -29,7 +29,7 @@ func loadModule(fn string, cfg Config) (*wrapModule, error) {
 	wmod := newWrapModule(mod)
 
 	logger.Infof("Analyze '%s'", fn)
-	if err := wmod.Visit(cfg.EntryFunc, analyze(wmod)); err != nil {
+	if err := wmod.Visit(cfg.EntryFunc, analyze(wmod), cfg); err != nil {
 		return nil, err
 	}
 	return wmod, nil