// 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, nil, lenParams, lenResults, false),
}
}
// newMethod creates a new method of the specified name, package and receiver type.
func newMethod(pkg *ssa.Package, recvType types.Type, name string) *ssa.Function {
// TODO(adonovan): fix: hack: currently the only part of Signature
// that is needed is the "pointerness" of Recv.Type, and for
// now, we'll set it to always be false since we're only
// concerned with rtype. Encapsulate this better.
sig := types.NewSignature(nil, types.NewVar(token.NoPos, nil, "recv", recvType), nil, nil, false)
fn := pkg.Prog.NewFunction(name, sig, "fake reflect method")
fn.Pkg = pkg
return fn
}
// FindTests returns the list of packages that define at least one Test,
// Example or Benchmark function (as defined by "go test"), and the
// lists of all such functions.
//
func FindTests(pkgs []*Package) (testpkgs []*Package, tests, benchmarks, examples []*Function) {
if len(pkgs) == 0 {
return
}
prog := pkgs[0].Prog
// The first two of these may be nil: if the program doesn't import "testing",
// it can't contain any tests, but it may yet contain Examples.
var testSig *types.Signature // func(*testing.T)
var benchmarkSig *types.Signature // func(*testing.B)
var exampleSig = types.NewSignature(nil, nil, nil, nil, false) // func()
// Obtain the types from the parameters of testing.Main().
if testingPkg := prog.ImportedPackage("testing"); testingPkg != nil {
params := testingPkg.Func("Main").Signature.Params()
testSig = funcField(params.At(1).Type())
benchmarkSig = funcField(params.At(2).Type())
}
seen := make(map[*Package]bool)
for _, pkg := range pkgs {
if pkg.Prog != prog {
panic("wrong Program")
}
// TODO(adonovan): use a stable order, e.g. lexical.
for _, mem := range pkg.Members {
if f, ok := mem.(*Function); ok &&
ast.IsExported(f.Name()) &&
strings.HasSuffix(prog.Fset.Position(f.Pos()).Filename, "_test.go") {
switch {
case testSig != nil && isTestSig(f, "Test", testSig):
tests = append(tests, f)
case benchmarkSig != nil && isTestSig(f, "Benchmark", benchmarkSig):
benchmarks = append(benchmarks, f)
case isTestSig(f, "Example", exampleSig):
examples = append(examples, f)
default:
continue
}
if !seen[pkg] {
seen[pkg] = true
testpkgs = append(testpkgs, pkg)
}
}
}
}
return
}
// Signature = Parameters [ Result ] .
// Result = Type | Parameters .
//
func (p *parser) parseSignature(recv *types.Var) *types.Signature {
params, isVariadic := p.parseParameters()
// optional result type
var results []*types.Var
if p.tok == '(' {
var variadic bool
results, variadic = p.parseParameters()
if variadic {
p.error("... not permitted on result type")
}
}
return types.NewSignature(nil, recv, types.NewTuple(params...), types.NewTuple(results...), isVariadic)
}
// makeWrapper returns a synthetic method that delegates to the
// declared method denoted by meth.Obj(), first performing any
// necessary pointer indirections or field selections implied by meth.
//
// The resulting method's receiver type is meth.Recv().
//
// This function is versatile but quite subtle! Consider the
// following axes of variation when making changes:
// - optional receiver indirection
// - optional implicit field selections
// - meth.Obj() may denote a concrete or an interface method
// - the result may be a thunk or a wrapper.
//
// EXCLUSIVE_LOCKS_REQUIRED(prog.methodsMu)
//
func makeWrapper(prog *Program, sel *types.Selection) *Function {
obj := sel.Obj().(*types.Func) // the declared function
sig := sel.Type().(*types.Signature) // type of this wrapper
var recv *types.Var // wrapper's receiver or thunk's params[0]
name := obj.Name()
var description string
var start int // first regular param
if sel.Kind() == types.MethodExpr {
name += "$thunk"
description = "thunk"
recv = sig.Params().At(0)
start = 1
} else {
description = "wrapper"
recv = sig.Recv()
}
description = fmt.Sprintf("%s for %s", description, sel.Obj())
if prog.mode&LogSource != 0 {
defer logStack("make %s to (%s)", description, recv.Type())()
}
fn := &Function{
name: name,
method: sel,
object: obj,
Signature: sig,
Synthetic: description,
Prog: prog,
pos: obj.Pos(),
}
fn.startBody()
fn.addSpilledParam(recv)
createParams(fn, start)
indices := sel.Index()
var v Value = fn.Locals[0] // spilled receiver
if isPointer(sel.Recv()) {
v = emitLoad(fn, v)
// For simple indirection wrappers, perform an informative nil-check:
// "value method (T).f called using nil *T pointer"
if len(indices) == 1 && !isPointer(recvType(obj)) {
var c Call
c.Call.Value = &Builtin{
name: "ssa:wrapnilchk",
sig: types.NewSignature(nil, nil,
types.NewTuple(anonVar(sel.Recv()), anonVar(tString), anonVar(tString)),
types.NewTuple(anonVar(sel.Recv())), false),
}
c.Call.Args = []Value{
v,
stringConst(deref(sel.Recv()).String()),
stringConst(sel.Obj().Name()),
}
c.setType(v.Type())
v = fn.emit(&c)
}
}
// Invariant: v is a pointer, either
// value of *A receiver param, or
// address of A spilled receiver.
// We use pointer arithmetic (FieldAddr possibly followed by
// Load) in preference to value extraction (Field possibly
// preceded by Load).
v = emitImplicitSelections(fn, v, indices[:len(indices)-1])
// Invariant: v is a pointer, either
// value of implicit *C field, or
// address of implicit C field.
var c Call
if r := recvType(obj); !isInterface(r) { // concrete method
if !isPointer(r) {
v = emitLoad(fn, v)
}
c.Call.Value = prog.declaredFunc(obj)
c.Call.Args = append(c.Call.Args, v)
} else {
c.Call.Method = obj
c.Call.Value = emitLoad(fn, v)
}
for _, arg := range fn.Params[1:] {
c.Call.Args = append(c.Call.Args, arg)
}
emitTailCall(fn, &c)
fn.finishBody()
return fn
}
func changeRecv(s *types.Signature, recv *types.Var) *types.Signature {
return types.NewSignature(nil, recv, s.Params(), s.Results(), s.Variadic())
}