1 files changed, 119 insertions, 0 deletions
diff --git a/vendor/golang.org/x/tools/go/ssa/util.go b/vendor/golang.org/x/tools/go/ssa/util.go
new file mode 100644
index 0000000..ddb1184
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/ssa/util.go
@@ -0,0 +1,119 @@
+// 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.
+
+package ssa
+
+// This file defines a number of miscellaneous utility functions.
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"go/types"
+	"io"
+	"os"
+
+	"golang.org/x/tools/go/ast/astutil"
+)
+
+//// AST utilities
+
+func unparen(e ast.Expr) ast.Expr { return astutil.Unparen(e) }
+
+// isBlankIdent returns true iff e is an Ident with name "_".
+// They have no associated types.Object, and thus no type.
+//
+func isBlankIdent(e ast.Expr) bool {
+	id, ok := e.(*ast.Ident)
+	return ok && id.Name == "_"
+}
+
+//// Type utilities.  Some of these belong in go/types.
+
+// isPointer returns true for types whose underlying type is a pointer.
+func isPointer(typ types.Type) bool {
+	_, ok := typ.Underlying().(*types.Pointer)
+	return ok
+}
+
+func isInterface(T types.Type) bool { return types.IsInterface(T) }
+
+// deref returns a pointer's element type; otherwise it returns typ.
+func deref(typ types.Type) types.Type {
+	if p, ok := typ.Underlying().(*types.Pointer); ok {
+		return p.Elem()
+	}
+	return typ
+}
+
+// recvType returns the receiver type of method obj.
+func recvType(obj *types.Func) types.Type {
+	return obj.Type().(*types.Signature).Recv().Type()
+}
+
+// DefaultType returns the default "typed" type for an "untyped" type;
+// it returns the incoming type for all other types.  The default type
+// for untyped nil is untyped nil.
+//
+// Exported to ssa/interp.
+//
+// TODO(adonovan): use go/types.DefaultType after 1.8.
+//
+func DefaultType(typ types.Type) types.Type {
+	if t, ok := typ.(*types.Basic); ok {
+		k := t.Kind()
+		switch k {
+		case types.UntypedBool:
+			k = types.Bool
+		case types.UntypedInt:
+			k = types.Int
+		case types.UntypedRune:
+			k = types.Rune
+		case types.UntypedFloat:
+			k = types.Float64
+		case types.UntypedComplex:
+			k = types.Complex128
+		case types.UntypedString:
+			k = types.String
+		}
+		typ = types.Typ[k]
+	}
+	return typ
+}
+
+// logStack prints the formatted "start" message to stderr and
+// returns a closure that prints the corresponding "end" message.
+// Call using 'defer logStack(...)()' to show builder stack on panic.
+// Don't forget trailing parens!
+//
+func logStack(format string, args ...interface{}) func() {
+	msg := fmt.Sprintf(format, args...)
+	io.WriteString(os.Stderr, msg)
+	io.WriteString(os.Stderr, "\n")
+	return func() {
+		io.WriteString(os.Stderr, msg)
+		io.WriteString(os.Stderr, " end\n")
+	}
+}
+
+// newVar creates a 'var' for use in a types.Tuple.
+func newVar(name string, typ types.Type) *types.Var {
+	return types.NewParam(token.NoPos, nil, name, typ)
+}
+
+// anonVar creates an anonymous 'var' for use in a types.Tuple.
+func anonVar(typ types.Type) *types.Var {
+	return newVar("", typ)
+}
+
+var lenResults = types.NewTuple(anonVar(tInt))
+
+// makeLen returns the len builtin specialized to type func(T)int.
+func makeLen(T types.Type) *Builtin {
+	lenParams := types.NewTuple(anonVar(T))
+	return &Builtin{
+		name: "len",
+		sig:  types.NewSignature(nil, lenParams, lenResults, false),
+	}
+}