Ejemplo n.º 1
0
Archivo: lex.go Proyecto: rsc/tmp
func importfile(f *Val, line int) {
	if f.Ctype != CTSTR {
		Yyerror("import statement not a string")
		fakeimport()
		return
	}

	if len(f.U.Sval) == 0 {
		Yyerror("import path is empty")
		fakeimport()
		return
	}

	if isbadimport(f.U.Sval) {
		fakeimport()
		return
	}

	// The package name main is no longer reserved,
	// but we reserve the import path "main" to identify
	// the main package, just as we reserve the import
	// path "math" to identify the standard math package.
	if f.U.Sval == "main" {
		Yyerror("cannot import \"main\"")
		errorexit()
	}

	if myimportpath != "" && f.U.Sval == myimportpath {
		Yyerror("import %q while compiling that package (import cycle)", f.U.Sval)
		errorexit()
	}

	if f.U.Sval == "unsafe" {
		if safemode != 0 {
			Yyerror("cannot import package unsafe")
			errorexit()
		}

		importpkg = mkpkg(f.U.Sval)
		cannedimports("unsafe.6", unsafeimport)
		imported_unsafe = 1
		return
	}

	path_ := f.U.Sval
	if islocalname(path_) {
		if path_[0] == '/' {
			Yyerror("import path cannot be absolute path")
			fakeimport()
			return
		}

		prefix := Ctxt.Pathname
		if localimport != "" {
			prefix = localimport
		}
		cleanbuf := prefix
		cleanbuf += "/"
		cleanbuf += path_
		cleanbuf = path.Clean(cleanbuf)
		path_ = cleanbuf

		if isbadimport(path_) {
			fakeimport()
			return
		}
	}

	file, found := findpkg(path_)
	if !found {
		Yyerror("can't find import: %q", f.U.Sval)
		errorexit()
	}

	importpkg = mkpkg(path_)

	// If we already saw that package, feed a dummy statement
	// to the lexer to avoid parsing export data twice.
	if importpkg.Imported != 0 {
		tag := ""
		if importpkg.Safe {
			tag = "safe"
		}

		p := fmt.Sprintf("package %s %s\n$$\n", importpkg.Name, tag)
		cannedimports(file, p)
		return
	}

	importpkg.Imported = 1

	var err error
	var imp *obj.Biobuf
	imp, err = obj.Bopenr(file)
	if err != nil {
		Yyerror("can't open import: %q: %v", f.U.Sval, err)
		errorexit()
	}

	if strings.HasSuffix(file, ".a") {
		if !skiptopkgdef(imp) {
			Yyerror("import %s: not a package file", file)
			errorexit()
		}
	}

	// check object header
	p := obj.Brdstr(imp, '\n', 1)

	if p != "empty archive" {
		if !strings.HasPrefix(p, "go object ") {
			Yyerror("import %s: not a go object file", file)
			errorexit()
		}

		q := fmt.Sprintf("%s %s %s %s", obj.Getgoos(), obj.Getgoarch(), obj.Getgoversion(), obj.Expstring())
		if p[10:] != q {
			Warn("WARNING ONLY: import %s: object is [%s] expected [%s]", file, p[10:], q)
			//errorexit()
		}
	}

	// assume files move (get installed)
	// so don't record the full path.
	linehist(file[len(file)-len(path_)-2:], -1, 1) // acts as #pragma lib

	/*
	 * position the input right
	 * after $$ and return
	 */
	pushedio = curio

	curio.bin = imp
	curio.peekc = 0
	curio.peekc1 = 0
	curio.infile = file
	curio.nlsemi = 0
	typecheckok = 1

	var c int32
	for {
		c = int32(getc())
		if c == EOF {
			break
		}
		if c != '$' {
			continue
		}
		c = int32(getc())
		if c == EOF {
			break
		}
		if c != '$' {
			continue
		}
		return
	}

	Yyerror("no import in %q", f.U.Sval)
	unimportfile()
}
Ejemplo n.º 2
0
Archivo: lex.go Proyecto: rsc/tmp
func Main() {
	defer hidePanic()

	// Allow GOARCH=thearch.thestring or GOARCH=thearch.thestringsuffix,
	// but not other values.
	p := obj.Getgoarch()

	if !strings.HasPrefix(p, Thearch.Thestring) {
		log.Fatalf("cannot use %cg with GOARCH=%s", Thearch.Thechar, p)
	}
	goarch = p

	Thearch.Linkarchinit()
	Ctxt = obj.Linknew(Thearch.Thelinkarch)
	Ctxt.Diag = Yyerror
	Ctxt.Bso = &bstdout
	bstdout = *obj.Binitw(os.Stdout)

	localpkg = mkpkg("")
	localpkg.Prefix = "\"\""

	// pseudo-package, for scoping
	builtinpkg = mkpkg("go.builtin")

	builtinpkg.Prefix = "go.builtin" // not go%2ebuiltin

	// pseudo-package, accessed by import "unsafe"
	unsafepkg = mkpkg("unsafe")

	unsafepkg.Name = "unsafe"

	// real package, referred to by generated runtime calls
	Runtimepkg = mkpkg("runtime")

	Runtimepkg.Name = "runtime"

	// pseudo-packages used in symbol tables
	gostringpkg = mkpkg("go.string")

	gostringpkg.Name = "go.string"
	gostringpkg.Prefix = "go.string" // not go%2estring

	itabpkg = mkpkg("go.itab")

	itabpkg.Name = "go.itab"
	itabpkg.Prefix = "go.itab" // not go%2eitab

	weaktypepkg = mkpkg("go.weak.type")

	weaktypepkg.Name = "go.weak.type"
	weaktypepkg.Prefix = "go.weak.type" // not go%2eweak%2etype

	typelinkpkg = mkpkg("go.typelink")
	typelinkpkg.Name = "go.typelink"
	typelinkpkg.Prefix = "go.typelink" // not go%2etypelink

	trackpkg = mkpkg("go.track")

	trackpkg.Name = "go.track"
	trackpkg.Prefix = "go.track" // not go%2etrack

	typepkg = mkpkg("type")

	typepkg.Name = "type"

	goroot = obj.Getgoroot()
	goos = obj.Getgoos()

	Nacl = goos == "nacl"
	if Nacl {
		flag_largemodel = 1
	}

	outfile = ""
	obj.Flagcount("+", "compiling runtime", &compiling_runtime)
	obj.Flagcount("%", "debug non-static initializers", &Debug['%'])
	obj.Flagcount("A", "for bootstrapping, allow 'any' type", &Debug['A'])
	obj.Flagcount("B", "disable bounds checking", &Debug['B'])
	obj.Flagstr("D", "path: set relative path for local imports", &localimport)
	obj.Flagcount("E", "debug symbol export", &Debug['E'])
	obj.Flagfn1("I", "dir: add dir to import search path", addidir)
	obj.Flagcount("K", "debug missing line numbers", &Debug['K'])
	obj.Flagcount("L", "use full (long) path in error messages", &Debug['L'])
	obj.Flagcount("M", "debug move generation", &Debug['M'])
	obj.Flagcount("N", "disable optimizations", &Debug['N'])
	obj.Flagcount("P", "debug peephole optimizer", &Debug['P'])
	obj.Flagcount("R", "debug register optimizer", &Debug['R'])
	obj.Flagcount("S", "print assembly listing", &Debug['S'])
	obj.Flagfn0("V", "print compiler version", doversion)
	obj.Flagcount("W", "debug parse tree after type checking", &Debug['W'])
	obj.Flagstr("asmhdr", "file: write assembly header to named file", &asmhdr)
	obj.Flagcount("complete", "compiling complete package (no C or assembly)", &pure_go)
	obj.Flagstr("d", "list: print debug information about items in list", &debugstr)
	obj.Flagcount("e", "no limit on number of errors reported", &Debug['e'])
	obj.Flagcount("f", "debug stack frames", &Debug['f'])
	obj.Flagcount("g", "debug code generation", &Debug['g'])
	obj.Flagcount("h", "halt on error", &Debug['h'])
	obj.Flagcount("i", "debug line number stack", &Debug['i'])
	obj.Flagstr("installsuffix", "pkg directory suffix", &flag_installsuffix)
	obj.Flagcount("j", "debug runtime-initialized variables", &Debug['j'])
	obj.Flagcount("l", "disable inlining", &Debug['l'])
	obj.Flagcount("live", "debug liveness analysis", &debuglive)
	obj.Flagcount("m", "print optimization decisions", &Debug['m'])
	obj.Flagcount("nolocalimports", "reject local (relative) imports", &nolocalimports)
	obj.Flagstr("o", "obj: set output file", &outfile)
	obj.Flagstr("p", "path: set expected package import path", &myimportpath)
	obj.Flagcount("pack", "write package file instead of object file", &writearchive)
	obj.Flagcount("r", "debug generated wrappers", &Debug['r'])
	obj.Flagcount("race", "enable race detector", &flag_race)
	obj.Flagcount("s", "warn about composite literals that can be simplified", &Debug['s'])
	obj.Flagstr("trimpath", "prefix: remove prefix from recorded source file paths", &Ctxt.LineHist.TrimPathPrefix)
	obj.Flagcount("u", "reject unsafe code", &safemode)
	obj.Flagcount("v", "increase debug verbosity", &Debug['v'])
	obj.Flagcount("w", "debug type checking", &Debug['w'])
	use_writebarrier = 1
	obj.Flagcount("wb", "enable write barrier", &use_writebarrier)
	obj.Flagcount("x", "debug lexer", &Debug['x'])
	obj.Flagcount("y", "debug declarations in canned imports (with -d)", &Debug['y'])
	var flag_shared int
	var flag_dynlink bool
	if Thearch.Thechar == '6' {
		obj.Flagcount("largemodel", "generate code that assumes a large memory model", &flag_largemodel)
		obj.Flagcount("shared", "generate code that can be linked into a shared library", &flag_shared)
		flag.BoolVar(&flag_dynlink, "dynlink", false, "support references to Go symbols defined in other shared libraries")
	}
	obj.Flagstr("cpuprofile", "file: write cpu profile to file", &cpuprofile)
	obj.Flagstr("memprofile", "file: write memory profile to file", &memprofile)
	obj.Flagint64("memprofilerate", "set runtime.MemProfileRate", &memprofilerate)
	obj.Flagparse(usage)

	if flag_dynlink {
		flag_shared = 1
	}
	Ctxt.Flag_shared = int32(flag_shared)
	Ctxt.Flag_dynlink = flag_dynlink

	Ctxt.Debugasm = int32(Debug['S'])
	Ctxt.Debugvlog = int32(Debug['v'])

	if flag.NArg() < 1 {
		usage()
	}

	startProfile()

	if flag_race != 0 {
		racepkg = mkpkg("runtime/race")
		racepkg.Name = "race"
	}

	// parse -d argument
	if debugstr != "" {
	Split:
		for _, name := range strings.Split(debugstr, ",") {
			if name == "" {
				continue
			}
			val := 1
			if i := strings.Index(name, "="); i >= 0 {
				var err error
				val, err = strconv.Atoi(name[i+1:])
				if err != nil {
					log.Fatalf("invalid debug value %v", name)
				}
				name = name[:i]
			}
			for _, t := range debugtab {
				if t.name == name {
					if t.val != nil {
						*t.val = val
						continue Split
					}
				}
			}
			log.Fatalf("unknown debug key -d %s\n", name)
		}
	}

	// enable inlining.  for now:
	//	default: inlining on.  (debug['l'] == 1)
	//	-l: inlining off  (debug['l'] == 0)
	//	-ll, -lll: inlining on again, with extra debugging (debug['l'] > 1)
	if Debug['l'] <= 1 {
		Debug['l'] = 1 - Debug['l']
	}

	Thearch.Betypeinit()
	if Widthptr == 0 {
		Fatal("betypeinit failed")
	}

	lexinit()
	typeinit()
	lexinit1()
	// TODO(rsc): Restore yytinit?

	blockgen = 1
	dclcontext = PEXTERN
	nerrors = 0
	lexlineno = 1

	for _, infile = range flag.Args() {
		linehist(infile, 0, 0)

		curio.infile = infile
		var err error
		curio.bin, err = obj.Bopenr(infile)
		if err != nil {
			fmt.Printf("open %s: %v\n", infile, err)
			errorexit()
		}

		curio.peekc = 0
		curio.peekc1 = 0
		curio.nlsemi = 0
		curio.eofnl = 0
		curio.last = 0

		// Skip initial BOM if present.
		if obj.Bgetrune(curio.bin) != obj.BOM {
			obj.Bungetrune(curio.bin)
		}

		block = 1
		iota_ = -1000000

		imported_unsafe = 0

		yyparse()
		if nsyntaxerrors != 0 {
			errorexit()
		}

		linehist("<pop>", 0, 0)
		if curio.bin != nil {
			obj.Bterm(curio.bin)
		}
	}

	testdclstack()
	mkpackage(localpkg.Name) // final import not used checks
	lexfini()

	typecheckok = 1
	if Debug['f'] != 0 {
		frame(1)
	}

	// Process top-level declarations in phases.

	// Phase 1: const, type, and names and types of funcs.
	//   This will gather all the information about types
	//   and methods but doesn't depend on any of it.
	defercheckwidth()

	for l := xtop; l != nil; l = l.Next {
		if l.N.Op != ODCL && l.N.Op != OAS {
			typecheck(&l.N, Etop)
		}
	}

	// Phase 2: Variable assignments.
	//   To check interface assignments, depends on phase 1.
	for l := xtop; l != nil; l = l.Next {
		if l.N.Op == ODCL || l.N.Op == OAS {
			typecheck(&l.N, Etop)
		}
	}
	resumecheckwidth()

	// Phase 3: Type check function bodies.
	for l := xtop; l != nil; l = l.Next {
		if l.N.Op == ODCLFUNC || l.N.Op == OCLOSURE {
			Curfn = l.N
			decldepth = 1
			saveerrors()
			typechecklist(l.N.Nbody, Etop)
			checkreturn(l.N)
			if nerrors != 0 {
				l.N.Nbody = nil // type errors; do not compile
			}
		}
	}

	// Phase 4: Decide how to capture closed variables.
	// This needs to run before escape analysis,
	// because variables captured by value do not escape.
	for l := xtop; l != nil; l = l.Next {
		if l.N.Op == ODCLFUNC && l.N.Closure != nil {
			Curfn = l.N
			capturevars(l.N)
		}
	}

	Curfn = nil

	if nsavederrors+nerrors != 0 {
		errorexit()
	}

	// Phase 5: Inlining
	if Debug['l'] > 1 {
		// Typecheck imported function bodies if debug['l'] > 1,
		// otherwise lazily when used or re-exported.
		for l := importlist; l != nil; l = l.Next {
			if l.N.Func.Inl != nil {
				saveerrors()
				typecheckinl(l.N)
			}
		}

		if nsavederrors+nerrors != 0 {
			errorexit()
		}
	}

	if Debug['l'] != 0 {
		// Find functions that can be inlined and clone them before walk expands them.
		visitBottomUp(xtop, func(list *NodeList, recursive bool) {
			for l := list; l != nil; l = l.Next {
				if l.N.Op == ODCLFUNC {
					caninl(l.N)
					inlcalls(l.N)
				}
			}
		})
	}

	// Phase 6: Escape analysis.
	// Required for moving heap allocations onto stack,
	// which in turn is required by the closure implementation,
	// which stores the addresses of stack variables into the closure.
	// If the closure does not escape, it needs to be on the stack
	// or else the stack copier will not update it.
	escapes(xtop)

	// Escape analysis moved escaped values off stack.
	// Move large values off stack too.
	movelarge(xtop)

	// Phase 7: Transform closure bodies to properly reference captured variables.
	// This needs to happen before walk, because closures must be transformed
	// before walk reaches a call of a closure.
	for l := xtop; l != nil; l = l.Next {
		if l.N.Op == ODCLFUNC && l.N.Closure != nil {
			Curfn = l.N
			transformclosure(l.N)
		}
	}

	Curfn = nil

	// Phase 8: Compile top level functions.
	for l := xtop; l != nil; l = l.Next {
		if l.N.Op == ODCLFUNC {
			funccompile(l.N)
		}
	}

	if nsavederrors+nerrors == 0 {
		fninit(xtop)
	}

	// Phase 9: Check external declarations.
	for l := externdcl; l != nil; l = l.Next {
		if l.N.Op == ONAME {
			typecheck(&l.N, Erv)
		}
	}

	if nerrors+nsavederrors != 0 {
		errorexit()
	}

	dumpobj()

	if asmhdr != "" {
		dumpasmhdr()
	}

	if nerrors+nsavederrors != 0 {
		errorexit()
	}

	Flusherrors()
}