--- /dev/null
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// ssadump: a tool for displaying and interpreting the SSA form of Go programs.
+package main // import "golang.org/x/tools/cmd/ssadump"
+
+import (
+ "flag"
+ "fmt"
+ "go/build"
+ "go/types"
+ "os"
+ "runtime"
+ "runtime/pprof"
+
+ "golang.org/x/tools/go/buildutil"
+ "golang.org/x/tools/go/packages"
+ "golang.org/x/tools/go/ssa"
+ "golang.org/x/tools/go/ssa/interp"
+ "golang.org/x/tools/go/ssa/ssautil"
+)
+
+// flags
+var (
+ mode = ssa.BuilderMode(0)
+
+ testFlag = flag.Bool("test", false, "include implicit test packages and executables")
+
+ runFlag = flag.Bool("run", false, "interpret the SSA program")
+
+ interpFlag = flag.String("interp", "", `Options controlling the SSA test interpreter.
+The value is a sequence of zero or more more of these letters:
+R disable [R]ecover() from panic; show interpreter crash instead.
+T [T]race execution of the program. Best for single-threaded programs!
+`)
+
+ cpuprofile = flag.String("cpuprofile", "", "write cpu profile to file")
+
+ args stringListValue
+)
+
+func init() {
+ flag.Var(&mode, "build", ssa.BuilderModeDoc)
+ flag.Var((*buildutil.TagsFlag)(&build.Default.BuildTags), "tags", buildutil.TagsFlagDoc)
+ flag.Var(&args, "arg", "add argument to interpreted program")
+}
+
+const usage = `SSA builder and interpreter.
+Usage: ssadump [-build=[DBCSNFL]] [-test] [-run] [-interp=[TR]] [-arg=...] package...
+Use -help flag to display options.
+
+Examples:
+% ssadump -build=F hello.go # dump SSA form of a single package
+% ssadump -build=F -test fmt # dump SSA form of a package and its tests
+% ssadump -run -interp=T hello.go # interpret a program, with tracing
+
+The -run flag causes ssadump to run the first package named main.
+
+Interpretation of the standard "testing" package is no longer supported.
+`
+
+func main() {
+ if err := doMain(); err != nil {
+ fmt.Fprintf(os.Stderr, "ssadump: %s\n", err)
+ os.Exit(1)
+ }
+}
+
+func doMain() error {
+ flag.Parse()
+ if len(flag.Args()) == 0 {
+ fmt.Fprint(os.Stderr, usage)
+ os.Exit(1)
+ }
+
+ cfg := &packages.Config{
+ Mode: packages.LoadSyntax,
+ Tests: *testFlag,
+ }
+
+ // Choose types.Sizes from conf.Build.
+ // TODO(adonovan): remove this when go/packages provides a better way.
+ var wordSize int64 = 8
+ switch build.Default.GOARCH {
+ case "386", "arm":
+ wordSize = 4
+ }
+ sizes := &types.StdSizes{
+ MaxAlign: 8,
+ WordSize: wordSize,
+ }
+
+ var interpMode interp.Mode
+ for _, c := range *interpFlag {
+ switch c {
+ case 'T':
+ interpMode |= interp.EnableTracing
+ case 'R':
+ interpMode |= interp.DisableRecover
+ default:
+ return fmt.Errorf("unknown -interp option: '%c'", c)
+ }
+ }
+
+ // Profiling support.
+ if *cpuprofile != "" {
+ f, err := os.Create(*cpuprofile)
+ if err != nil {
+ fmt.Fprintln(os.Stderr, err)
+ os.Exit(1)
+ }
+ pprof.StartCPUProfile(f)
+ defer pprof.StopCPUProfile()
+ }
+
+ // Load, parse and type-check the initial packages,
+ // and, if -run, their dependencies.
+ if *runFlag {
+ cfg.Mode = packages.LoadAllSyntax
+ }
+ initial, err := packages.Load(cfg, flag.Args()...)
+ if err != nil {
+ return err
+ }
+ if len(initial) == 0 {
+ return fmt.Errorf("no packages")
+ }
+ if packages.PrintErrors(initial) > 0 {
+ return fmt.Errorf("packages contain errors")
+ }
+
+ // Create SSA-form program representation.
+ prog, pkgs := ssautil.AllPackages(initial, mode)
+
+ for i, p := range pkgs {
+ if p == nil {
+ return fmt.Errorf("cannot build SSA for package %s", initial[i])
+ }
+ }
+
+ if !*runFlag {
+ // Build and display only the initial packages
+ // (and synthetic wrappers).
+ for _, p := range pkgs {
+ p.Build()
+ }
+
+ } else {
+ // Run the interpreter.
+ // Build SSA for all packages.
+ prog.Build()
+
+ // The interpreter needs the runtime package.
+ // It is a limitation of go/packages that
+ // we cannot add "runtime" to its initial set,
+ // we can only check that it is present.
+ if prog.ImportedPackage("runtime") == nil {
+ return fmt.Errorf("-run: program does not depend on runtime")
+ }
+
+ if runtime.GOARCH != build.Default.GOARCH {
+ return fmt.Errorf("cross-interpretation is not supported (target has GOARCH %s, interpreter has %s)",
+ build.Default.GOARCH, runtime.GOARCH)
+ }
+
+ // Run first main package.
+ for _, main := range ssautil.MainPackages(pkgs) {
+ fmt.Fprintf(os.Stderr, "Running: %s\n", main.Pkg.Path())
+ os.Exit(interp.Interpret(main, interpMode, sizes, main.Pkg.Path(), args))
+ }
+ return fmt.Errorf("no main package")
+ }
+ return nil
+}
+
+// stringListValue is a flag.Value that accumulates strings.
+// e.g. --flag=one --flag=two would produce []string{"one", "two"}.
+type stringListValue []string
+
+func newStringListValue(val []string, p *[]string) *stringListValue {
+ *p = val
+ return (*stringListValue)(p)
+}
+
+func (ss *stringListValue) Get() interface{} { return []string(*ss) }
+
+func (ss *stringListValue) String() string { return fmt.Sprintf("%q", *ss) }
+
+func (ss *stringListValue) Set(s string) error { *ss = append(*ss, s); return nil }