go.tools/ssa: dump types in "pkg."-unqualified form where appropriate.

Also: types.Typ[types.UnsafePointer].String() now always prints as "unsafe.Pointer".

R=gri
CC=golang-dev
https://golang.org/cl/21820044

go/types/errors.go

@@ -228,6 +228,9 @@ func writeType(buf *bytes.Buffer, typ Type) {
 		buf.WriteString("<nil>")
 
 	case *Basic:
+		if t.Kind() == UnsafePointer {
+			buf.WriteString("unsafe.")
+		}
 		buf.WriteString(t.name)
 
 	case *Array:

go/types/gcimporter_test.go

@@ -119,7 +119,7 @@ var importedObjectTests = []struct {
 	kind ast.ObjKind
 	typ  string
 }{
-	{"unsafe.Pointer", ast.Typ, "Pointer"},
+	{"unsafe.Pointer", ast.Typ, "unsafe.Pointer"},
 	{"math.Pi", ast.Con, "untyped float"},
 	{"io.Reader", ast.Typ, "interface{Read(p []byte) (n int, err error)}"},
 	{"io.ReadWriter", ast.Typ, "interface{Read(p []byte) (n int, err error); Write(p []byte) (n int, err error)}"},

ssa/builder.go

@@ -578,8 +578,8 @@ func (b *builder) expr0(fn *Function, e ast.Expr) Value {
 			return emitArith(fn, e.Op, b.expr(fn, e.X), b.expr(fn, e.Y), fn.Pkg.typeOf(e), e.OpPos)
 
 		case token.EQL, token.NEQ, token.GTR, token.LSS, token.LEQ, token.GEQ:
-			// TODO(gri): we shouldn't need DefaultType here.
 			cmp := emitCompare(fn, e.Op, b.expr(fn, e.X), b.expr(fn, e.Y), e.OpPos)
+			// The type of x==y may be UntypedBool.
 			return emitConv(fn, cmp, DefaultType(fn.Pkg.typeOf(e)))
 		default:
 			panic("illegal op in BinaryExpr: " + e.Op.String())
@@ -2221,7 +2221,7 @@ func (p *Package) Build() {
 		init.emit(&v)
 	}
 
-	b := new(builder)
+	var b builder
 
 	// Initialize package-level vars in correct order.
 	for _, varinit := range p.info.InitOrder {

ssa/func.go

@@ -499,7 +499,7 @@ func (f *Function) fullName(from *Package) string {
 // writeSignature writes to w the signature sig in declaration syntax.
 // Derived from types.Signature.String().
 //
-func writeSignature(w io.Writer, name string, sig *types.Signature, params []*Parameter) {
+func writeSignature(w io.Writer, pkg *Package, name string, sig *types.Signature, params []*Parameter) {
 	io.WriteString(w, "func ")
 	if recv := sig.Recv(); recv != nil {
 		io.WriteString(w, "(")
@@ -507,7 +507,7 @@ func writeSignature(w io.Writer, name string, sig *types.Signature, params []*Pa
 			io.WriteString(w, n)
 			io.WriteString(w, " ")
 		}
-		io.WriteString(w, params[0].Type().String())
+		io.WriteString(w, relType(params[0].Type(), pkg))
 		io.WriteString(w, ") ")
 		params = params[1:]
 	}
@@ -521,9 +521,9 @@ func writeSignature(w io.Writer, name string, sig *types.Signature, params []*Pa
 		io.WriteString(w, " ")
 		if sig.IsVariadic() && i == len(params)-1 {
 			io.WriteString(w, "...")
-			io.WriteString(w, v.Type().Underlying().(*types.Slice).Elem().String())
+			io.WriteString(w, relType(v.Type().Underlying().(*types.Slice).Elem(), pkg))
 		} else {
-			io.WriteString(w, v.Type().String())
+			io.WriteString(w, relType(v.Type(), pkg))
 		}
 	}
 	io.WriteString(w, ")")
@@ -531,9 +531,9 @@ func writeSignature(w io.Writer, name string, sig *types.Signature, params []*Pa
 		io.WriteString(w, " ")
 		r := sig.Results()
 		if n == 1 && r.At(0).Name() == "" {
-			io.WriteString(w, r.At(0).Type().String())
+			io.WriteString(w, relType(r.At(0).Type(), pkg))
 		} else {
-			io.WriteString(w, r.String())
+			io.WriteString(w, r.String()) // TODO(adonovan): use relType
 		}
 	}
 }
@@ -561,18 +561,18 @@ func (f *Function) DumpTo(w io.Writer) {
 	if f.FreeVars != nil {
 		io.WriteString(w, "# Free variables:\n")
 		for i, fv := range f.FreeVars {
-			fmt.Fprintf(w, "# % 3d:\t%s %s\n", i, fv.Name(), fv.Type())
+			fmt.Fprintf(w, "# % 3d:\t%s %s\n", i, fv.Name(), relType(fv.Type(), f.Pkg))
 		}
 	}
 
 	if len(f.Locals) > 0 {
 		io.WriteString(w, "# Locals:\n")
 		for i, l := range f.Locals {
-			fmt.Fprintf(w, "# % 3d:\t%s %s\n", i, l.Name(), deref(l.Type()))
+			fmt.Fprintf(w, "# % 3d:\t%s %s\n", i, l.Name(), relType(deref(l.Type()), f.Pkg))
 		}
 	}
 
-	writeSignature(w, f.Name(), f.Signature, f.Params)
+	writeSignature(w, f.Pkg, f.Name(), f.Signature, f.Params)
 	io.WriteString(w, ":\n")
 
 	if f.Blocks == nil {
@@ -603,11 +603,12 @@ func (f *Function) DumpTo(w io.Writer) {
 					n, _ := fmt.Fprintf(w, "%s = ", name)
 					l -= n
 				}
+				// TODO(adonovan): append instructions directly to w.
 				n, _ := io.WriteString(w, instr.String())
 				l -= n
 				// Right-align the type.
 				if t := v.Type(); t != nil {
-					fmt.Fprintf(w, " %*s", l-10, t)
+					fmt.Fprintf(w, " %*s", l-10, relType(t, f.Pkg))
 				}
 			case nil:
 				// Be robust against bad transforms.

ssa/print.go

@@ -48,13 +48,6 @@ func relName(v Value, i Instruction) string {
 // TODO(gri): provide this functionality in go/types (using a
 // *types.Package, obviously).
 //
-// TODO(adonovan): use this more widely, e.g.
-// ChangeType, Literal, Convert, MakeInterface;
-// when displaying receiver, params, locals, captures of a Function;
-// and in the RHS type column for Value-defining Instructions.
-//
-// TODO(adonovan): fix: unsafe.Pointer has no ssa.Package.
-//
 func relType(t types.Type, from *Package) string {
 	if from != nil {
 		t2 := t
@@ -177,7 +170,7 @@ func (v *Call) String() string {
 }
 
 func (v *ChangeType) String() string {
-	return fmt.Sprintf("changetype %s <- %s (%s)", v.Type(), v.X.Type(), relName(v.X, v))
+	return fmt.Sprintf("changetype %s <- %s (%s)", relType(v.Type(), v.Parent().Pkg), v.X.Type(), relName(v.X, v))
 }
 
 func (v *BinOp) String() string {
@@ -189,7 +182,7 @@ func (v *UnOp) String() string {
 }
 
 func (v *Convert) String() string {
-	return fmt.Sprintf("convert %s <- %s (%s)", v.Type(), v.X.Type(), relName(v.X, v))
+	return fmt.Sprintf("convert %s <- %s (%s)", relType(v.Type(), v.Parent().Pkg), v.X.Type(), relName(v.X, v))
 }
 
 func (v *ChangeInterface) String() string {
@@ -197,7 +190,7 @@ func (v *ChangeInterface) String() string {
 }
 
 func (v *MakeInterface) String() string {
-	return fmt.Sprintf("make %s <- %s (%s)", v.Type(), v.X.Type(), relName(v.X, v))
+	return fmt.Sprintf("make %s <- %s (%s)", relType(v.Type(), v.Parent().Pkg), relType(v.X.Type(), v.Parent().Pkg), relName(v.X, v))
 }
 
 func (v *MakeClosure) String() string {