go.tools/ssa: move AllFunctions to ssautil subpackage

R=gri
CC=golang-dev
https://golang.org/cl/37970043

oracle/peers.go

@@ -14,6 +14,7 @@ import (
 	"code.google.com/p/go.tools/oracle/serial"
 	"code.google.com/p/go.tools/pointer"
 	"code.google.com/p/go.tools/ssa"
+	"code.google.com/p/go.tools/ssa/ssautil"
 )
 
 // peers enumerates, for a given channel send (or receive) operation,
@@ -36,7 +37,7 @@ func peers(o *Oracle, qpos *QueryPos) (queryResult, error) {
 
 	// Look at all send/receive instructions in the whole ssa.Program.
 	// Build a list of those of same type to query.
-	allFuncs := ssa.AllFunctions(o.prog)
+	allFuncs := ssautil.AllFunctions(o.prog)
 	for fn := range allFuncs {
 		for _, b := range fn.Blocks {
 			for _, instr := range b.Instrs {

ssa/doc.go

@@ -114,14 +114,12 @@
 // either accurate or unambiguous.  The public API exposes a number of
 // name-based maps for client convenience.
 //
+// The ssa/ssautil package provides various utilities that depend only
+// on the public API of this package.
+//
 // TODO(adonovan): Consider the exceptional control-flow implications
 // of defer and recover().
 //
-// TODO(adonovan): write an example showing how to visit all functions
-// in a Program, including package init functions, methods of named
-// and anon types, and functions used as values but never called
-// directly.  See AllFunctions().
-//
 // TODO(adonovan): write a how-to document for all the various cases
 // of trying to determine corresponding elements across the four
 // domains of source locations, ast.Nodes, types.Objects,

ssa/ssautil/visit.go

@@ -2,7 +2,9 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package ssa
+package ssautil
+
+import "code.google.com/p/go.tools/ssa"
 
 // This file defines utilities for visiting the SSA representation of
 // a Program.
@@ -17,24 +19,24 @@ package ssa
 //
 // Precondition: all packages are built.
 //
-func AllFunctions(prog *Program) map[*Function]bool {
+func AllFunctions(prog *ssa.Program) map[*ssa.Function]bool {
 	visit := visitor{
 		prog: prog,
-		seen: make(map[*Function]bool),
+		seen: make(map[*ssa.Function]bool),
 	}
 	visit.program()
 	return visit.seen
 }
 
 type visitor struct {
-	prog *Program
+	prog *ssa.Program
-	seen map[*Function]bool
+	seen map[*ssa.Function]bool
 }
 
 func (visit *visitor) program() {
 	for _, pkg := range visit.prog.AllPackages() {
 		for _, mem := range pkg.Members {
-			if fn, ok := mem.(*Function); ok {
+			if fn, ok := mem.(*ssa.Function); ok {
 				visit.function(fn)
 			}
 		}
@@ -47,14 +49,14 @@ func (visit *visitor) program() {
 	}
 }
 
-func (visit *visitor) function(fn *Function) {
+func (visit *visitor) function(fn *ssa.Function) {
 	if !visit.seen[fn] {
 		visit.seen[fn] = true
+		var buf [10]*ssa.Value // avoid alloc in common case
 		for _, b := range fn.Blocks {
 			for _, instr := range b.Instrs {
-				var buf [10]*Value // avoid alloc in common case
 				for _, op := range instr.Operands(buf[:0]) {
-					if fn, ok := (*op).(*Function); ok {
+					if fn, ok := (*op).(*ssa.Function); ok {
 						visit.function(fn)
 					}
 				}

ssa/stdlib_test.go

@@ -21,6 +21,7 @@ import (
 
 	"code.google.com/p/go.tools/importer"
 	"code.google.com/p/go.tools/ssa"
+	"code.google.com/p/go.tools/ssa/ssautil"
 )
 
 const debugMode = false
@@ -97,7 +98,7 @@ func TestStdlib(t *testing.T) {
 	}
 
 	// Dump some statistics.
-	allFuncs := ssa.AllFunctions(prog)
+	allFuncs := ssautil.AllFunctions(prog)
 	var numInstrs int
 	for fn := range allFuncs {
 		for _, b := range fn.Blocks {