- import/export cleanup: added comments, removed dead code, re-org structure

R=r
OCL=13816
CL=13816

usr/gri/gosrc/export.go

@@ -21,9 +21,7 @@ type Exporter struct {
 };
 
 
-func (E *Exporter) WriteType(typ *Globals.Type);
 func (E *Exporter) WriteObject(obj *Globals.Object);
-func (E *Exporter) WritePackage(pno int);
 
 
 func (E *Exporter) WriteByte(x byte) {
@@ -65,13 +63,14 @@ func (E *Exporter) WriteString(s string) {
 }
 
 
-func (E *Exporter) WriteObjectTag(tag int) {
-	if tag < 0 {
-		panic "tag < 0";
-	}
+func (E *Exporter) WritePackageTag(tag int) {
 	E.WriteInt(tag);
 	if E.debug {
-		print "\n", Object.KindStr(tag);
+		if tag >= 0 {
+			print " [P", tag, "]";  // package ref
+		} else {
+			print "\nP", E.pkg_ref, ":";
+		}
 	}
 }
 
@@ -88,27 +87,44 @@ func (E *Exporter) WriteTypeTag(tag int) {
 }
 
 
-func (E *Exporter) WritePackageTag(tag int) {
+func (E *Exporter) WriteObjectTag(tag int) {
+	if tag < 0 {
+		panic "tag < 0";
+	}
 	E.WriteInt(tag);
 	if E.debug {
-		if tag >= 0 {
-			print " [P", tag, "]";  // package ref
-		} else {
-			print "\nP", E.pkg_ref, ":";
-		}
+		print "\n", Object.KindStr(tag);
+	}
+}
+
+
+func (E *Exporter) WritePackage(pkg *Globals.Package) {
+	if E.comp.pkg_list[pkg.obj.pnolev] != pkg {
+		panic "inconsistent package object"
+	}
+
+	if pkg.ref >= 0 {
+		E.WritePackageTag(pkg.ref);  // package already exported
+		return;
 	}
+
+	E.WritePackageTag(-1);
+	pkg.ref = E.pkg_ref;
+	E.pkg_ref++;
+
+	E.WriteString(pkg.obj.ident);
+	E.WriteString(pkg.file_name);
+	E.WriteString(pkg.key);
 }
 
 
-func (E *Exporter) WriteScope(scope *Globals.Scope, export_all bool) {
+func (E *Exporter) WriteScope(scope *Globals.Scope) {
 	if E.debug {
 		print " {";
 	}
 
 	for p := scope.entries.first; p != nil; p = p.next {
-		if export_all || p.obj.exported {
-			E.WriteObject(p.obj);
-		}
+		E.WriteObject(p.obj);
 	}
 	E.WriteObject(nil);
 	
@@ -118,42 +134,6 @@ func (E *Exporter) WriteScope(scope *Globals.Scope, export_all bool) {
 }
 
 
-func (E *Exporter) WriteObject(obj *Globals.Object) {
-	if obj == nil {
-		E.WriteObjectTag(Object.END);
-		return;
-	}
-
-	E.WriteObjectTag(obj.kind);
-	if obj.kind == Object.TYPE {
-		// named types are always primary types
-		// and handled entirely by WriteType()
-		if obj.typ.obj != obj {
-			panic "inconsistent primary type"
-		}
-		E.WriteType(obj.typ);
-		return;
-	}
-
-	E.WriteString(obj.ident);
-	E.WriteType(obj.typ);
-
-	switch obj.kind {
-	case Object.CONST:
-		E.WriteInt(0);  // should be the correct value
-
-	case Object.VAR:
-		E.WriteInt(0);  // should be the correct address/offset
-		
-	case Object.FUNC:
-		E.WriteInt(0);  // should be the correct address/offset
-		
-	default:
-		panic "UNREACHABLE";
-	}
-}
-
-
 func (E *Exporter) WriteType(typ *Globals.Type) {
 	if typ.ref >= 0 {
 		E.WriteTypeTag(typ.ref);  // type already exported
@@ -161,18 +141,18 @@ func (E *Exporter) WriteType(typ *Globals.Type) {
 	}
 
 	if -typ.form >= 0 {
-		panic "-typ.form >= 0";  // conflict with ref numbers
+		panic "conflict with ref numbers";
 	}
 	E.WriteTypeTag(-typ.form);
 	typ.ref = E.type_ref;
 	E.type_ref++;
 
-	// if we have a primary type, export the type identifier and package
+	// if we have a named type, export the type identifier and package
 	ident := "";
 	if typ.obj != nil {
-		// primary type
+		// named type
 		if typ.obj.typ != typ {
-			panic "inconsistent primary type";
+			panic "inconsistent named type";
 		}
 		ident = typ.obj.ident;
 		if !typ.obj.exported {
@@ -185,8 +165,8 @@ func (E *Exporter) WriteType(typ *Globals.Type) {
 	
 	E.WriteString(ident);
 	if len(ident) > 0 {
-		// primary type
-		E.WritePackage(typ.obj.pnolev);
+		// named type
+		E.WritePackage(E.comp.pkg_list[typ.obj.pnolev]);
 	}
 	
 	switch typ.form {
@@ -207,10 +187,10 @@ func (E *Exporter) WriteType(typ *Globals.Type) {
 
 	case Type.FUNCTION:
 		E.WriteInt(typ.flags);
-		E.WriteScope(typ.scope, true);
+		E.WriteScope(typ.scope);
 		
 	case Type.STRUCT, Type.INTERFACE:
-		E.WriteScope(typ.scope, true);  // for now
+		E.WriteScope(typ.scope);
 
 	case Type.POINTER, Type.REFERENCE:
 		E.WriteType(typ.elt);
@@ -221,23 +201,38 @@ func (E *Exporter) WriteType(typ *Globals.Type) {
 }
 
 
-func (E *Exporter) WritePackage(pno int) {
-	if pno < 0 {
-		pno = 0;
+func (E *Exporter) WriteObject(obj *Globals.Object) {
+	if obj == nil {
+		E.WriteObjectTag(Object.END);
+		return;
 	}
-	pkg := E.comp.pkg_list[pno];
-	if pkg.ref >= 0 {
-		E.WritePackageTag(pkg.ref);  // package already exported
+	E.WriteObjectTag(obj.kind);
+
+	if obj.kind == Object.TYPE {
+		// named types are handled entirely by WriteType()
+		if obj.typ.obj != obj {
+			panic "inconsistent named type"
+		}
+		E.WriteType(obj.typ);
 		return;
 	}
 
-	E.WritePackageTag(-1);
-	pkg.ref = E.pkg_ref;
-	E.pkg_ref++;
+	E.WriteString(obj.ident);
+	E.WriteType(obj.typ);
 
-	E.WriteString(pkg.obj.ident);
-	E.WriteString(pkg.file_name);
-	E.WriteString(pkg.key);
+	switch obj.kind {
+	case Object.CONST:
+		E.WriteInt(0);  // should be the correct value
+
+	case Object.VAR:
+		E.WriteInt(0);  // should be the correct address/offset
+		
+	case Object.FUNC:
+		E.WriteInt(0);  // should be the correct address/offset
+		
+	default:
+		panic "UNREACHABLE";
+	}
 }
 
 
@@ -264,9 +259,15 @@ func (E *Exporter) Export(comp* Globals.Compilation, file_name string) {
 	}
 	E.type_ref = Universe.types.len_;
 	
+	// export package 0
 	pkg := comp.pkg_list[0];
-	E.WritePackage(0);
-	E.WriteScope(pkg.scope, false);
+	E.WritePackage(pkg);
+	for p := pkg.scope.entries.first; p != nil; p = p.next {
+		if p.obj.exported {
+			E.WriteObject(p.obj);
+		}
+	}
+	E.WriteObject(nil);
 	
 	if E.debug {
 		print "\n(", E.buf_pos, " bytes)\n";

usr/gri/gosrc/globals.go

@@ -126,12 +126,13 @@ func NewType(form int) *Type {
 
 
 export NewPackage;
-func NewPackage(file_name string, obj *Object) *Package {
+func NewPackage(file_name string, obj *Object, scope *Scope) *Package {
 	pkg := new(Package);
 	pkg.ref = -1;  // not yet exported
 	pkg.file_name = file_name;
 	pkg.key = "<the package key>";  // TODO fix this
 	pkg.obj = obj;
+	pkg.scope = scope;
 	return pkg;
 }
 
@@ -316,14 +317,3 @@ func (C *Compilation) Insert(pkg *Package) {
 	C.pkg_list[C.pkg_ref] = pkg;
 	C.pkg_ref++;
 }
-
-
-func (C *Compilation) InsertImport(pkg *Package) *Package {
-	p := C.Lookup(pkg.file_name);
-	if (p == nil) {
-		// no primary package found
-		C.Insert(pkg);
-		p = pkg;
-	}
-	return p;
-}

usr/gri/gosrc/import.go

@@ -23,9 +23,7 @@ type Importer struct {
 };
 
 
-func (I *Importer) ReadType() *Globals.Type;
 func (I *Importer) ReadObject() *Globals.Object;
-func (I *Importer) ReadPackage() *Globals.Package;
 
 
 func (I *Importer) ReadByte() byte {
@@ -74,13 +72,14 @@ func (I *Importer) ReadString() string {
 }
 
 
-func (I *Importer) ReadObjectTag() int {
+func (I *Importer) ReadPackageTag() int {
 	tag := I.ReadInt();
-	if tag < 0 {
-		panic "tag < 0";
-	}
 	if I.debug {
-		print "\n", Object.KindStr(tag);
+		if tag >= 0 {
+			print " [P", tag, "]";  // package ref
+		} else {
+			print "\nP", I.pkg_ref, ":";
+		}
 	}
 	return tag;
 }
@@ -99,19 +98,48 @@ func (I *Importer) ReadTypeTag() int {
 }
 
 
-func (I *Importer) ReadPackageTag() int {
+func (I *Importer) ReadObjectTag() int {
 	tag := I.ReadInt();
+	if tag < 0 {
+		panic "tag < 0";
+	}
 	if I.debug {
-		if tag >= 0 {
-			print " [P", tag, "]";  // package ref
-		} else {
-			print "\nP", I.pkg_ref, ":";
-		}
+		print "\n", Object.KindStr(tag);
 	}
 	return tag;
 }
 
 
+func (I *Importer) ReadPackage() *Globals.Package {
+	tag := I.ReadPackageTag();
+	if tag >= 0 {
+		return I.pkg_list[tag];  // package already imported
+	}
+
+	ident := I.ReadString();
+	file_name := I.ReadString();
+	key := I.ReadString();
+	
+	// Canonicalize package - if it was imported before,
+	// use the primary import.
+	pkg := I.comp.Lookup(file_name);
+	if pkg == nil {
+		// new package
+		obj := Globals.NewObject(-1, Object.PACKAGE, ident);
+		pkg = Globals.NewPackage(file_name, obj, Globals.NewScope(nil));
+		I.comp.Insert(pkg);
+	} else if key != pkg.key {
+		// the package was imported before but the package
+		// key has changed
+		panic "package key inconsistency";
+	}
+	I.pkg_list[I.pkg_ref] = pkg;
+	I.pkg_ref++;
+
+	return pkg;
+}
+
+
 func (I *Importer) ReadScope() *Globals.Scope {
 	if I.debug {
 		print " {";
@@ -120,7 +148,7 @@ func (I *Importer) ReadScope() *Globals.Scope {
 	scope := Globals.NewScope(nil);
 	obj := I.ReadObject();
 	for obj != nil {
-		scope.InsertImport(obj);
+		scope.Insert(obj);
 		obj = I.ReadObject();
 	}
 	
@@ -132,44 +160,6 @@ func (I *Importer) ReadScope() *Globals.Scope {
 }
 
 
-func (I *Importer) ReadObject() *Globals.Object {
-	tag := I.ReadObjectTag();
-	if tag == Object.END {
-		return nil;
-	}
-	
-	if tag == Object.TYPE {
-		// named types are always primary types
-		// and handled entirely by ReadType()
-		typ := I.ReadType();
-		if typ.obj.typ != typ {
-			panic "inconsistent primary type";
-		}
-		return typ.obj;
-	}
-	
-	ident := I.ReadString();
-	obj := Globals.NewObject(0, tag, ident);
-	obj.typ = I.ReadType();
-
-	switch (tag) {
-	case Object.CONST:
-		I.ReadInt();  // should set the value field
-
-	case Object.VAR:
-		I.ReadInt();  // should set the address/offset field
-
-	case Object.FUNC:
-		I.ReadInt();  // should set the address/offset field
-		
-	default:
-		panic "UNREACHABLE";
-	}
-
-	return obj;
-}
-
-
 func (I *Importer) ReadType() *Globals.Type {
 	tag := I.ReadTypeTag();
 	if tag >= 0 {
@@ -181,7 +171,7 @@ func (I *Importer) ReadType() *Globals.Type {
 
 	ident := I.ReadString();
 	if len(ident) > 0 {
-		// primary type
+		// named type
 		pkg := I.ReadPackage();
 		
 		// create corresponding type object
@@ -234,32 +224,40 @@ func (I *Importer) ReadType() *Globals.Type {
 }
 
 
-func (I *Importer) ReadPackage() *Globals.Package {
-	tag := I.ReadPackageTag();
-	if tag >= 0 {
-		return I.pkg_list[tag];  // package already imported
+func (I *Importer) ReadObject() *Globals.Object {
+	tag := I.ReadObjectTag();
+	if tag == Object.END {
+		return nil;
 	}
-
+	
+	if tag == Object.TYPE {
+		// named types are handled entirely by ReadType()
+		typ := I.ReadType();
+		if typ.obj.typ != typ {
+			panic "inconsistent named type";
+		}
+		return typ.obj;
+	}
+	
 	ident := I.ReadString();
-	file_name := I.ReadString();
-	key := I.ReadString();
-	pkg := I.comp.Lookup(file_name);
+	obj := Globals.NewObject(0, tag, ident);
+	obj.typ = I.ReadType();
 
-	if pkg == nil {
-		// new package
-		obj := Globals.NewObject(-1, Object.PACKAGE, ident);
-		pkg = Globals.NewPackage(file_name, obj);
-		pkg.scope = Globals.NewScope(nil);
-		pkg = I.comp.InsertImport(pkg);
+	switch (tag) {
+	case Object.CONST:
+		I.ReadInt();  // should set the value field
 
-	} else if key != pkg.key {
-		// package inconsistency
-		panic "package key inconsistency";
+	case Object.VAR:
+		I.ReadInt();  // should set the address/offset field
+
+	case Object.FUNC:
+		I.ReadInt();  // should set the address/offset field
+		
+	default:
+		panic "UNREACHABLE";
 	}
-	I.pkg_list[I.pkg_ref] = pkg;
-	I.pkg_ref++;
 
-	return pkg;
+	return obj;
 }
 
 
@@ -290,14 +288,16 @@ func (I *Importer) Import(comp* Globals.Compilation, file_name string) *Globals.
 		I.type_ref++;
 	}
 
+	// import package
 	pkg := I.ReadPackage();
-	obj := I.ReadObject();
-	for obj != nil {
-		obj.pnolev = pkg.obj.pnolev;
-		pkg.scope.InsertImport(obj);
-		obj = I.ReadObject();
+	{	obj := I.ReadObject();
+		for obj != nil {
+			obj.pnolev = pkg.obj.pnolev;
+			pkg.scope.InsertImport(obj);
+			obj = I.ReadObject();
+		}
 	}
-
+	
 	if I.debug {
 		print "\n(", I.buf_pos, " bytes)\n";
 	}

usr/gri/gosrc/parser.go

@@ -1917,18 +1917,18 @@ func (P *Parser) ParseProgram() {
 	P.OpenScope();
 	P.Expect(Scanner.PACKAGE);
 	obj := P.ParseIdentDecl(Object.PACKAGE);
-	pkg := Globals.NewPackage(P.S.filename, obj);
-	P.comp.Insert(pkg);
-	if P.comp.pkg_ref != 1 {
-		panic "should have exactly one package now";
-	}
 	P.Optional(Scanner.SEMICOLON);
 	
 	{	if P.level != 0 {
 			panic "incorrect scope level";
 		}
 		P.OpenScope();
-		pkg.scope = P.top_scope;
+		
+		P.comp.Insert(Globals.NewPackage(P.S.filename, obj, P.top_scope));
+		if P.comp.pkg_ref != 1 {
+			panic "should have exactly one package now";
+		}
+
 		for P.tok == Scanner.IMPORT {
 			P.ParseDecl(false, Scanner.IMPORT);
 			P.Optional(Scanner.SEMICOLON);