--- /dev/null
+// Copyright 2015 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 ssautil
+
+// This file defines utility functions for constructing programs in SSA form.
+
+import (
+ "go/ast"
+ "go/token"
+ "go/types"
+
+ "golang.org/x/tools/go/loader"
+ "golang.org/x/tools/go/packages"
+ "golang.org/x/tools/go/ssa"
+)
+
+// Packages creates an SSA program for a set of packages.
+//
+// The packages must have been loaded from source syntax using the
+// golang.org/x/tools/go/packages.Load function in LoadSyntax or
+// LoadAllSyntax mode.
+//
+// Packages creates an SSA package for each well-typed package in the
+// initial list, plus all their dependencies. The resulting list of
+// packages corresponds to the list of initial packages, and may contain
+// a nil if SSA code could not be constructed for the corresponding initial
+// package due to type errors.
+//
+// Code for bodies of functions is not built until Build is called on
+// the resulting Program. SSA code is constructed only for the initial
+// packages with well-typed syntax trees.
+//
+// The mode parameter controls diagnostics and checking during SSA construction.
+//
+func Packages(initial []*packages.Package, mode ssa.BuilderMode) (*ssa.Program, []*ssa.Package) {
+ return doPackages(initial, mode, false)
+}
+
+// AllPackages creates an SSA program for a set of packages plus all
+// their dependencies.
+//
+// The packages must have been loaded from source syntax using the
+// golang.org/x/tools/go/packages.Load function in LoadAllSyntax mode.
+//
+// AllPackages creates an SSA package for each well-typed package in the
+// initial list, plus all their dependencies. The resulting list of
+// packages corresponds to the list of initial packages, and may contain
+// a nil if SSA code could not be constructed for the corresponding
+// initial package due to type errors.
+//
+// Code for bodies of functions is not built until Build is called on
+// the resulting Program. SSA code is constructed for all packages with
+// well-typed syntax trees.
+//
+// The mode parameter controls diagnostics and checking during SSA construction.
+//
+func AllPackages(initial []*packages.Package, mode ssa.BuilderMode) (*ssa.Program, []*ssa.Package) {
+ return doPackages(initial, mode, true)
+}
+
+func doPackages(initial []*packages.Package, mode ssa.BuilderMode, deps bool) (*ssa.Program, []*ssa.Package) {
+
+ var fset *token.FileSet
+ if len(initial) > 0 {
+ fset = initial[0].Fset
+ }
+
+ prog := ssa.NewProgram(fset, mode)
+
+ isInitial := make(map[*packages.Package]bool, len(initial))
+ for _, p := range initial {
+ isInitial[p] = true
+ }
+
+ ssamap := make(map[*packages.Package]*ssa.Package)
+ packages.Visit(initial, nil, func(p *packages.Package) {
+ if p.Types != nil && !p.IllTyped {
+ var files []*ast.File
+ if deps || isInitial[p] {
+ files = p.Syntax
+ }
+ ssamap[p] = prog.CreatePackage(p.Types, files, p.TypesInfo, true)
+ }
+ })
+
+ var ssapkgs []*ssa.Package
+ for _, p := range initial {
+ ssapkgs = append(ssapkgs, ssamap[p]) // may be nil
+ }
+ return prog, ssapkgs
+}
+
+// CreateProgram returns a new program in SSA form, given a program
+// loaded from source. An SSA package is created for each transitively
+// error-free package of lprog.
+//
+// Code for bodies of functions is not built until Build is called
+// on the result.
+//
+// The mode parameter controls diagnostics and checking during SSA construction.
+//
+// Deprecated: Use golang.org/x/tools/go/packages and the Packages
+// function instead; see ssa.ExampleLoadPackages.
+//
+func CreateProgram(lprog *loader.Program, mode ssa.BuilderMode) *ssa.Program {
+ prog := ssa.NewProgram(lprog.Fset, mode)
+
+ for _, info := range lprog.AllPackages {
+ if info.TransitivelyErrorFree {
+ prog.CreatePackage(info.Pkg, info.Files, &info.Info, info.Importable)
+ }
+ }
+
+ return prog
+}
+
+// BuildPackage builds an SSA program with IR for a single package.
+//
+// It populates pkg by type-checking the specified file ASTs. All
+// dependencies are loaded using the importer specified by tc, which
+// typically loads compiler export data; SSA code cannot be built for
+// those packages. BuildPackage then constructs an ssa.Program with all
+// dependency packages created, and builds and returns the SSA package
+// corresponding to pkg.
+//
+// The caller must have set pkg.Path() to the import path.
+//
+// The operation fails if there were any type-checking or import errors.
+//
+// See ../ssa/example_test.go for an example.
+//
+func BuildPackage(tc *types.Config, fset *token.FileSet, pkg *types.Package, files []*ast.File, mode ssa.BuilderMode) (*ssa.Package, *types.Info, error) {
+ if fset == nil {
+ panic("no token.FileSet")
+ }
+ if pkg.Path() == "" {
+ panic("package has no import path")
+ }
+
+ info := &types.Info{
+ Types: make(map[ast.Expr]types.TypeAndValue),
+ Defs: make(map[*ast.Ident]types.Object),
+ Uses: make(map[*ast.Ident]types.Object),
+ Implicits: make(map[ast.Node]types.Object),
+ Scopes: make(map[ast.Node]*types.Scope),
+ Selections: make(map[*ast.SelectorExpr]*types.Selection),
+ }
+ if err := types.NewChecker(tc, fset, pkg, info).Files(files); err != nil {
+ return nil, nil, err
+ }
+
+ prog := ssa.NewProgram(fset, mode)
+
+ // Create SSA packages for all imports.
+ // Order is not significant.
+ created := make(map[*types.Package]bool)
+ var createAll func(pkgs []*types.Package)
+ createAll = func(pkgs []*types.Package) {
+ for _, p := range pkgs {
+ if !created[p] {
+ created[p] = true
+ prog.CreatePackage(p, nil, nil, true)
+ createAll(p.Imports())
+ }
+ }
+ }
+ createAll(pkg.Imports())
+
+ // Create and build the primary package.
+ ssapkg := prog.CreatePackage(pkg, files, info, false)
+ ssapkg.Build()
+ return ssapkg, info, nil
+}