func (d *DIBuilder) descriptorInterface(t *types.Interface, name string) llvm.Metadata {
ifaceStruct := types.NewStruct([]*types.Var{
types.NewVar(0, nil, "type", types.NewPointer(types.Typ[types.Uint8])),
types.NewVar(0, nil, "data", types.NewPointer(types.Typ[types.Uint8])),
}, nil)
return d.typeDebugDescriptor(ifaceStruct, name)
}
// emitNew emits to f a new (heap Alloc) instruction allocating an
// object of type typ. pos is the optional source location.
//
func emitNew(f *Function, typ types.Type, pos token.Pos) *Alloc {
v := &Alloc{Heap: true}
v.setType(types.NewPointer(typ))
v.setPos(pos)
f.emit(v)
return v
}
// emitFieldSelection emits to f code to select the index'th field of v.
//
// If wantAddr, the input must be a pointer-to-struct and the result
// will be the field's address; otherwise the result will be the
// field's value.
// Ident id is used for position and debug info.
//
func emitFieldSelection(f *Function, v Value, index int, wantAddr bool, id *ast.Ident) Value {
fld := deref(v.Type()).Underlying().(*types.Struct).Field(index)
if isPointer(v.Type()) {
instr := &FieldAddr{
X: v,
Field: index,
}
instr.setPos(id.Pos())
instr.setType(types.NewPointer(fld.Type()))
v = f.emit(instr)
// Load the field's value iff we don't want its address.
if !wantAddr {
v = emitLoad(f, v)
}
} else {
instr := &Field{
X: v,
Field: index,
}
instr.setPos(id.Pos())
instr.setType(fld.Type())
v = f.emit(instr)
}
emitDebugRef(f, id, v, wantAddr)
return v
}
// emitImplicitSelections emits to f code to apply the sequence of
// implicit field selections specified by indices to base value v, and
// returns the selected value.
//
// If v is the address of a struct, the result will be the address of
// a field; if it is the value of a struct, the result will be the
// value of a field.
//
func emitImplicitSelections(f *Function, v Value, indices []int) Value {
for _, index := range indices {
fld := deref(v.Type()).Underlying().(*types.Struct).Field(index)
if isPointer(v.Type()) {
instr := &FieldAddr{
X: v,
Field: index,
}
instr.setType(types.NewPointer(fld.Type()))
v = f.emit(instr)
// Load the field's value iff indirectly embedded.
if isPointer(fld.Type()) {
v = emitLoad(f, v)
}
} else {
instr := &Field{
X: v,
Field: index,
}
instr.setType(fld.Type())
v = f.emit(instr)
}
}
return v
}
// PointerType = "*" ("any" | Type) .
func (p *parser) parsePointerType(pkg *types.Package) types.Type {
p.expect('*')
if p.tok == scanner.Ident {
p.expectKeyword("any")
return types.Typ[types.UnsafePointer]
}
return types.NewPointer(p.parseType(pkg))
}
func (d *DIBuilder) descriptorSlice(t *types.Slice, name string) llvm.Metadata {
sliceStruct := types.NewStruct([]*types.Var{
types.NewVar(0, nil, "ptr", types.NewPointer(t.Elem())),
types.NewVar(0, nil, "len", types.Typ[types.Int]),
types.NewVar(0, nil, "cap", types.Typ[types.Int]),
}, nil)
return d.typeDebugDescriptor(sliceStruct, name)
}
// addLocal creates an anonymous local variable of type typ, adds it
// to function f and returns it. pos is the optional source location.
//
func (f *Function) addLocal(typ types.Type, pos token.Pos) *Alloc {
v := &Alloc{}
v.setType(types.NewPointer(typ))
v.setPos(pos)
f.Locals = append(f.Locals, v)
f.emit(v)
return v
}
// memberFromObject populates package pkg with a member for the
// typechecker object obj.
//
// For objects from Go source code, syntax is the associated syntax
// tree (for funcs and vars only); it will be used during the build
// phase.
//
func memberFromObject(pkg *Package, obj types.Object, syntax ast.Node) {
name := obj.Name()
switch obj := obj.(type) {
case *types.TypeName:
pkg.Members[name] = &Type{
object: obj,
pkg: pkg,
}
case *types.Const:
c := &NamedConst{
object: obj,
Value: NewConst(obj.Val(), obj.Type()),
pkg: pkg,
}
pkg.values[obj] = c.Value
pkg.Members[name] = c
case *types.Var:
g := &Global{
Pkg: pkg,
name: name,
object: obj,
typ: types.NewPointer(obj.Type()), // address
pos: obj.Pos(),
}
pkg.values[obj] = g
pkg.Members[name] = g
case *types.Func:
sig := obj.Type().(*types.Signature)
if sig.Recv() == nil && name == "init" {
pkg.ninit++
name = fmt.Sprintf("init#%d", pkg.ninit)
}
fn := &Function{
name: name,
object: obj,
Signature: sig,
syntax: syntax,
pos: obj.Pos(),
Pkg: pkg,
Prog: pkg.Prog,
}
if syntax == nil {
fn.Synthetic = "loaded from gc object file"
}
pkg.values[obj] = fn
if sig.Recv() == nil {
pkg.Members[name] = fn // package-level function
}
default: // (incl. *types.Package)
panic("unexpected Object type: " + obj.String())
}
}
// mapIterInit creates a map iterator
func (fr *frame) mapIterInit(m *govalue) []*govalue {
// We represent an iterator as a tuple (map, *bool). The second element
// controls whether the code we generate for "next" (below) calls the
// runtime function for the first or the next element. We let the
// optimizer reorganize this into something more sensible.
isinit := fr.allocaBuilder.CreateAlloca(llvm.Int1Type(), "")
fr.builder.CreateStore(llvm.ConstNull(llvm.Int1Type()), isinit)
return []*govalue{m, newValue(isinit, types.NewPointer(types.Typ[types.Bool]))}
}
// addSpilledParam declares a parameter that is pre-spilled to the
// stack; the function body will load/store the spilled location.
// Subsequent lifting will eliminate spills where possible.
//
func (f *Function) addSpilledParam(obj types.Object) {
param := f.addParamObj(obj)
spill := &Alloc{Comment: obj.Name()}
spill.setType(types.NewPointer(obj.Type()))
spill.setPos(obj.Pos())
f.objects[obj] = spill
f.Locals = append(f.Locals, spill)
f.emit(spill)
f.emit(&Store{Addr: spill, Val: param})
}
// testMainSlice emits to fn code to construct a slice of type slice
// (one of []testing.Internal{Test,Benchmark,Example}) for all
// functions in testfuncs. It returns the slice value.
//
func testMainSlice(fn *Function, testfuncs []*Function, slice types.Type) Value {
if testfuncs == nil {
return nilConst(slice)
}
tElem := slice.(*types.Slice).Elem()
tPtrString := types.NewPointer(tString)
tPtrElem := types.NewPointer(tElem)
tPtrFunc := types.NewPointer(funcField(slice))
// Emit: array = new [n]testing.InternalTest
tArray := types.NewArray(tElem, int64(len(testfuncs)))
array := emitNew(fn, tArray, token.NoPos)
array.Comment = "test main"
for i, testfunc := range testfuncs {
// Emit: pitem = &array[i]
ia := &IndexAddr{X: array, Index: intConst(int64(i))}
ia.setType(tPtrElem)
pitem := fn.emit(ia)
// Emit: pname = &pitem.Name
fa := &FieldAddr{X: pitem, Field: 0} // .Name
fa.setType(tPtrString)
pname := fn.emit(fa)
// Emit: *pname = "testfunc"
emitStore(fn, pname, stringConst(testfunc.Name()), token.NoPos)
// Emit: pfunc = &pitem.F
fa = &FieldAddr{X: pitem, Field: 1} // .F
fa.setType(tPtrFunc)
pfunc := fn.emit(fa)
// Emit: *pfunc = testfunc
emitStore(fn, pfunc, testfunc, token.NoPos)
}
// Emit: slice array[:]
sl := &Slice{X: array}
sl.setType(slice)
return fn.emit(sl)
}
// Type =
// BasicType | TypeName | ArrayType | SliceType | StructType |
// PointerType | FuncType | InterfaceType | MapType | ChanType |
// "(" Type ")" .
//
// BasicType = ident .
// TypeName = ExportedName .
// SliceType = "[" "]" Type .
// PointerType = "*" Type .
// FuncType = "func" Signature .
//
func (p *parser) parseType() types.Type {
switch p.tok {
case scanner.Ident:
switch p.lit {
default:
return p.parseBasicType()
case "struct":
return p.parseStructType()
case "func":
// FuncType
p.next()
return p.parseSignature(nil)
case "interface":
return p.parseInterfaceType()
case "map":
return p.parseMapType()
case "chan":
return p.parseChanType()
}
case '@':
// TypeName
pkg, name := p.parseExportedName()
return declTypeName(pkg, name).Type()
case '[':
p.next() // look ahead
if p.tok == ']' {
// SliceType
p.next()
return types.NewSlice(p.parseType())
}
return p.parseArrayType()
case '*':
// PointerType
p.next()
return types.NewPointer(p.parseType())
case '<':
return p.parseChanType()
case '(':
// "(" Type ")"
p.next()
typ := p.parseType()
p.expect(')')
return typ
}
p.errorf("expected type, got %s (%q)", scanner.TokenString(p.tok), p.lit)
return nil
}
// callInstruction translates function call instructions.
func (fr *frame) callInstruction(instr ssa.CallInstruction) []*govalue {
call := instr.Common()
if builtin, ok := call.Value.(*ssa.Builtin); ok {
var typ types.Type
if v := instr.Value(); v != nil {
typ = v.Type()
}
return fr.callBuiltin(typ, builtin, call.Args)
}
args := make([]*govalue, len(call.Args))
for i, arg := range call.Args {
args[i] = fr.value(arg)
}
var fn *govalue
var chain llvm.Value
if call.IsInvoke() {
var recv *govalue
fn, recv = fr.interfaceMethod(fr.llvmvalue(call.Value), call.Value.Type(), call.Method)
args = append([]*govalue{recv}, args...)
} else {
if ssafn, ok := call.Value.(*ssa.Function); ok {
llfn := fr.resolveFunctionGlobal(ssafn)
llfn = llvm.ConstBitCast(llfn, llvm.PointerType(llvm.Int8Type(), 0))
fn = newValue(llfn, ssafn.Type())
} else {
// First-class function values are stored as *{*fnptr}, so
// we must extract the function pointer. We must also
// set the chain, in case the function is a closure.
fn = fr.value(call.Value)
chain = fn.value
fnptr := fr.builder.CreateBitCast(fn.value, llvm.PointerType(fn.value.Type(), 0), "")
fnptr = fr.builder.CreateLoad(fnptr, "")
fn = newValue(fnptr, fn.Type())
}
if recv := call.Signature().Recv(); recv != nil {
if _, ok := recv.Type().Underlying().(*types.Pointer); !ok {
recvalloca := fr.allocaBuilder.CreateAlloca(args[0].value.Type(), "")
fr.builder.CreateStore(args[0].value, recvalloca)
args[0] = newValue(recvalloca, types.NewPointer(args[0].Type()))
}
}
}
return fr.createCall(fn, chain, args)
}
func (tm *llvmTypeMap) getSignatureInfo(sig *types.Signature) functionTypeInfo {
var args, results []types.Type
if sig.Recv() != nil {
recvtype := sig.Recv().Type()
if _, ok := recvtype.Underlying().(*types.Pointer); !ok && recvtype != types.Typ[types.UnsafePointer] {
recvtype = types.NewPointer(recvtype)
}
args = []types.Type{recvtype}
}
for i := 0; i != sig.Params().Len(); i++ {
args = append(args, sig.Params().At(i).Type())
}
for i := 0; i != sig.Results().Len(); i++ {
results = append(results, sig.Results().At(i).Type())
}
return tm.getFunctionTypeInfo(args, results)
}
// IntuitiveMethodSet returns the intuitive method set of a type, T.
//
// The result contains MethodSet(T) and additionally, if T is a
// concrete type, methods belonging to *T if there is no identically
// named method on T itself. This corresponds to user intuition about
// method sets; this function is intended only for user interfaces.
//
// The order of the result is as for types.MethodSet(T).
//
func IntuitiveMethodSet(T types.Type, msets *types.MethodSetCache) []*types.Selection {
var result []*types.Selection
mset := msets.MethodSet(T)
if _, ok := T.Underlying().(*types.Interface); ok {
for i, n := 0, mset.Len(); i < n; i++ {
result = append(result, mset.At(i))
}
} else {
pmset := msets.MethodSet(types.NewPointer(T))
for i, n := 0, pmset.Len(); i < n; i++ {
meth := pmset.At(i)
if m := mset.Lookup(meth.Obj().Pkg(), meth.Obj().Name()); m != nil {
meth = m
}
result = append(result, meth)
}
}
return result
}
// Smoke test to ensure that imported methods get the correct package.
func TestCorrectMethodPackage(t *testing.T) {
// This package does not handle gccgo export data.
if runtime.Compiler == "gccgo" {
return
}
imports := make(map[string]*types.Package)
_, err := Import(imports, "net/http")
if err != nil {
t.Fatal(err)
}
mutex := imports["sync"].Scope().Lookup("Mutex").(*types.TypeName).Type()
mset := types.NewMethodSet(types.NewPointer(mutex)) // methods of *sync.Mutex
sel := mset.Lookup(nil, "Lock")
lock := sel.Obj().(*types.Func)
if got, want := lock.Pkg().Path(), "sync"; got != want {
t.Errorf("got package path %q; want %q", got, want)
}
}
// findNamedFunc returns the named function whose FuncDecl.Ident is at
// position pos.
//
func findNamedFunc(pkg *Package, pos token.Pos) *Function {
// Look at all package members and method sets of named types.
// Not very efficient.
for _, mem := range pkg.Members {
switch mem := mem.(type) {
case *Function:
if mem.Pos() == pos {
return mem
}
case *Type:
mset := pkg.Prog.MethodSets.MethodSet(types.NewPointer(mem.Type()))
for i, n := 0, mset.Len(); i < n; i++ {
// Don't call Program.Method: avoid creating wrappers.
obj := mset.At(i).Obj().(*types.Func)
if obj.Pos() == pos {
return pkg.values[obj].(*Function)
}
}
}
}
return nil
}
func (d *DIBuilder) descriptorBasic(t *types.Basic, name string) llvm.Metadata {
switch t.Kind() {
case types.String:
return d.typeDebugDescriptor(types.NewStruct([]*types.Var{
types.NewVar(0, nil, "ptr", types.NewPointer(types.Typ[types.Uint8])),
types.NewVar(0, nil, "len", types.Typ[types.Int]),
}, nil), name)
case types.UnsafePointer:
return d.builder.CreateBasicType(llvm.DIBasicType{
Name: name,
SizeInBits: uint64(d.sizes.Sizeof(t) * 8),
AlignInBits: uint64(d.sizes.Alignof(t) * 8),
Encoding: llvm.DW_ATE_unsigned,
})
default:
bt := llvm.DIBasicType{
Name: t.String(),
SizeInBits: uint64(d.sizes.Sizeof(t) * 8),
AlignInBits: uint64(d.sizes.Alignof(t) * 8),
}
switch bi := t.Info(); {
case bi&types.IsBoolean != 0:
bt.Encoding = llvm.DW_ATE_boolean
case bi&types.IsUnsigned != 0:
bt.Encoding = llvm.DW_ATE_unsigned
case bi&types.IsInteger != 0:
bt.Encoding = llvm.DW_ATE_signed
case bi&types.IsFloat != 0:
bt.Encoding = llvm.DW_ATE_float
case bi&types.IsComplex != 0:
bt.Encoding = llvm.DW_ATE_imaginary_float
case bi&types.IsUnsigned != 0:
bt.Encoding = llvm.DW_ATE_unsigned
default:
panic(fmt.Sprintf("unhandled: %#v", t))
}
return d.builder.CreateBasicType(bt)
}
}
func checkVarValue(t *testing.T, prog *ssa.Program, pkg *ssa.Package, ref []ast.Node, obj *types.Var, expKind string, wantAddr bool) {
// The prefix of all assertions messages.
prefix := fmt.Sprintf("VarValue(%s @ L%d)",
obj, prog.Fset.Position(ref[0].Pos()).Line)
v, gotAddr := prog.VarValue(obj, pkg, ref)
// Kind is the concrete type of the ssa Value.
gotKind := "nil"
if v != nil {
gotKind = fmt.Sprintf("%T", v)[len("*ssa."):]
}
// fmt.Printf("%s = %v (kind %q; expect %q) wantAddr=%t gotAddr=%t\n", prefix, v, gotKind, expKind, wantAddr, gotAddr) // debugging
// Check the kinds match.
// "nil" indicates expected failure (e.g. optimized away).
if expKind != gotKind {
t.Errorf("%s concrete type == %s, want %s", prefix, gotKind, expKind)
}
// Check the types match.
// If wantAddr, the expected type is the object's address.
if v != nil {
expType := obj.Type()
if wantAddr {
expType = types.NewPointer(expType)
if !gotAddr {
t.Errorf("%s: got value, want address", prefix)
}
} else if gotAddr {
t.Errorf("%s: got address, want value", prefix)
}
if !types.Identical(v.Type(), expType) {
t.Errorf("%s.Type() == %s, want %s", prefix, v.Type(), expType)
}
}
}
// Tests that programs partially loaded from gc object files contain
// functions with no code for the external portions, but are otherwise ok.
func TestImportFromBinary(t *testing.T) {
test := `
package main
import (
"bytes"
"io"
"testing"
)
func main() {
var t testing.T
t.Parallel() // static call to external declared method
t.Fail() // static call to promoted external declared method
testing.Short() // static call to external package-level function
var w io.Writer = new(bytes.Buffer)
w.Write(nil) // interface invoke of external declared method
}
`
// Create a single-file main package.
conf := loader.Config{ImportFromBinary: true}
f, err := conf.ParseFile("<input>", test)
if err != nil {
t.Error(err)
return
}
conf.CreateFromFiles("main", f)
iprog, err := conf.Load()
if err != nil {
t.Error(err)
return
}
prog := ssa.Create(iprog, ssa.SanityCheckFunctions)
mainPkg := prog.Package(iprog.Created[0].Pkg)
mainPkg.Build()
// The main package, its direct and indirect dependencies are loaded.
deps := []string{
// directly imported dependencies:
"bytes", "io", "testing",
// indirect dependencies (partial list):
"errors", "fmt", "os", "runtime",
}
all := prog.AllPackages()
if len(all) <= len(deps) {
t.Errorf("unexpected set of loaded packages: %q", all)
}
for _, path := range deps {
pkg := prog.ImportedPackage(path)
if pkg == nil {
t.Errorf("package not loaded: %q", path)
continue
}
// External packages should have no function bodies (except for wrappers).
isExt := pkg != mainPkg
// init()
if isExt && !isEmpty(pkg.Func("init")) {
t.Errorf("external package %s has non-empty init", pkg)
} else if !isExt && isEmpty(pkg.Func("init")) {
t.Errorf("main package %s has empty init", pkg)
}
for _, mem := range pkg.Members {
switch mem := mem.(type) {
case *ssa.Function:
// Functions at package level.
if isExt && !isEmpty(mem) {
t.Errorf("external function %s is non-empty", mem)
} else if !isExt && isEmpty(mem) {
t.Errorf("function %s is empty", mem)
}
case *ssa.Type:
// Methods of named types T.
// (In this test, all exported methods belong to *T not T.)
if !isExt {
t.Fatalf("unexpected name type in main package: %s", mem)
}
mset := prog.MethodSets.MethodSet(types.NewPointer(mem.Type()))
for i, n := 0, mset.Len(); i < n; i++ {
m := prog.Method(mset.At(i))
// For external types, only synthetic wrappers have code.
expExt := !strings.Contains(m.Synthetic, "wrapper")
if expExt && !isEmpty(m) {
t.Errorf("external method %s is non-empty: %s",
m, m.Synthetic)
} else if !expExt && isEmpty(m) {
t.Errorf("method function %s is empty: %s",
m, m.Synthetic)
}
}
}
}
}
expectedCallee := []string{
"(*testing.T).Parallel",
"(*testing.common).Fail",
"testing.Short",
"N/A",
}
callNum := 0
for _, b := range mainPkg.Func("main").Blocks {
for _, instr := range b.Instrs {
switch instr := instr.(type) {
case ssa.CallInstruction:
call := instr.Common()
if want := expectedCallee[callNum]; want != "N/A" {
got := call.StaticCallee().String()
if want != got {
t.Errorf("call #%d from main.main: got callee %s, want %s",
callNum, got, want)
}
}
callNum++
}
}
}
if callNum != 4 {
t.Errorf("in main.main: got %d calls, want %d", callNum, 4)
}
}
// addRuntimeType is called for each concrete type that can be the
// dynamic type of some interface or reflect.Value.
// Adapted from needMethods in go/ssa/builder.go
//
func (r *rta) addRuntimeType(T types.Type, skip bool) {
if prev, ok := r.result.RuntimeTypes.At(T).(bool); ok {
if skip && !prev {
r.result.RuntimeTypes.Set(T, skip)
}
return
}
r.result.RuntimeTypes.Set(T, skip)
mset := r.prog.MethodSets.MethodSet(T)
if _, ok := T.Underlying().(*types.Interface); !ok {
// T is a new concrete type.
for i, n := 0, mset.Len(); i < n; i++ {
sel := mset.At(i)
m := sel.Obj()
if m.Exported() {
// Exported methods are always potentially callable via reflection.
r.addReachable(r.prog.Method(sel), true)
}
}
// Add callgraph edge for each existing dynamic
// "invoke"-mode call via that interface.
for _, I := range r.interfaces(T) {
sites, _ := r.invokeSites.At(I).([]ssa.CallInstruction)
for _, site := range sites {
r.addInvokeEdge(site, T)
}
}
}
// Precondition: T is not a method signature (*Signature with Recv()!=nil).
// Recursive case: skip => don't call makeMethods(T).
// Each package maintains its own set of types it has visited.
var n *types.Named
switch T := T.(type) {
case *types.Named:
n = T
case *types.Pointer:
n, _ = T.Elem().(*types.Named)
}
if n != nil {
owner := n.Obj().Pkg()
if owner == nil {
return // built-in error type
}
}
// Recursion over signatures of each exported method.
for i := 0; i < mset.Len(); i++ {
if mset.At(i).Obj().Exported() {
sig := mset.At(i).Type().(*types.Signature)
r.addRuntimeType(sig.Params(), true) // skip the Tuple itself
r.addRuntimeType(sig.Results(), true) // skip the Tuple itself
}
}
switch t := T.(type) {
case *types.Basic:
// nop
case *types.Interface:
// nop---handled by recursion over method set.
case *types.Pointer:
r.addRuntimeType(t.Elem(), false)
case *types.Slice:
r.addRuntimeType(t.Elem(), false)
case *types.Chan:
r.addRuntimeType(t.Elem(), false)
case *types.Map:
r.addRuntimeType(t.Key(), false)
r.addRuntimeType(t.Elem(), false)
case *types.Signature:
if t.Recv() != nil {
panic(fmt.Sprintf("Signature %s has Recv %s", t, t.Recv()))
}
r.addRuntimeType(t.Params(), true) // skip the Tuple itself
r.addRuntimeType(t.Results(), true) // skip the Tuple itself
case *types.Named:
// A pointer-to-named type can be derived from a named
// type via reflection. It may have methods too.
r.addRuntimeType(types.NewPointer(T), false)
// Consider 'type T struct{S}' where S has methods.
// Reflection provides no way to get from T to struct{S},
// only to S, so the method set of struct{S} is unwanted,
// so set 'skip' flag during recursion.
r.addRuntimeType(t.Underlying(), true)
case *types.Array:
r.addRuntimeType(t.Elem(), false)
case *types.Struct:
for i, n := 0, t.NumFields(); i < n; i++ {
r.addRuntimeType(t.Field(i).Type(), false)
}
case *types.Tuple:
for i, n := 0, t.Len(); i < n; i++ {
r.addRuntimeType(t.At(i).Type(), false)
}
default:
panic(T)
}
}
func ext۰reflect۰New(fr *frame, args []value) value {
// Signature: func (t reflect.Type) reflect.Value
t := args[0].(iface).v.(rtype).t
alloc := zero(t)
return makeReflectValue(types.NewPointer(t), &alloc)
}
// Analyze runs the pointer analysis with the scope and options
// specified by config, and returns the (synthetic) root of the callgraph.
//
// Pointer analysis of a transitively closed well-typed program should
// always succeed. An error can occur only due to an internal bug.
//
func Analyze(config *Config) (result *Result, err error) {
if config.Mains == nil {
return nil, fmt.Errorf("no main/test packages to analyze (check $GOROOT/$GOPATH)")
}
defer func() {
if p := recover(); p != nil {
err = fmt.Errorf("internal error in pointer analysis: %v (please report this bug)", p)
fmt.Fprintln(os.Stderr, "Internal panic in pointer analysis:")
debug.PrintStack()
}
}()
a := &analysis{
config: config,
log: config.Log,
prog: config.prog(),
globalval: make(map[ssa.Value]nodeid),
globalobj: make(map[ssa.Value]nodeid),
flattenMemo: make(map[types.Type][]*fieldInfo),
trackTypes: make(map[types.Type]bool),
atFuncs: make(map[*ssa.Function]bool),
hasher: typeutil.MakeHasher(),
intrinsics: make(map[*ssa.Function]intrinsic),
result: &Result{
Queries: make(map[ssa.Value]Pointer),
IndirectQueries: make(map[ssa.Value]Pointer),
},
deltaSpace: make([]int, 0, 100),
}
if false {
a.log = os.Stderr // for debugging crashes; extremely verbose
}
if a.log != nil {
fmt.Fprintln(a.log, "==== Starting analysis")
}
// Pointer analysis requires a complete program for soundness.
// Check to prevent accidental misconfiguration.
for _, pkg := range a.prog.AllPackages() {
// (This only checks that the package scope is complete,
// not that func bodies exist, but it's a good signal.)
if !pkg.Object.Complete() {
return nil, fmt.Errorf(`pointer analysis requires a complete program yet package %q was incomplete (don't set loader.Config.ImportFromBinary during loading)`, pkg.Object.Path())
}
}
if reflect := a.prog.ImportedPackage("reflect"); reflect != nil {
rV := reflect.Object.Scope().Lookup("Value")
a.reflectValueObj = rV
a.reflectValueCall = a.prog.LookupMethod(rV.Type(), nil, "Call")
a.reflectType = reflect.Object.Scope().Lookup("Type").Type().(*types.Named)
a.reflectRtypeObj = reflect.Object.Scope().Lookup("rtype")
a.reflectRtypePtr = types.NewPointer(a.reflectRtypeObj.Type())
// Override flattening of reflect.Value, treating it like a basic type.
tReflectValue := a.reflectValueObj.Type()
a.flattenMemo[tReflectValue] = []*fieldInfo{{typ: tReflectValue}}
// Override shouldTrack of reflect.Value and *reflect.rtype.
// Always track pointers of these types.
a.trackTypes[tReflectValue] = true
a.trackTypes[a.reflectRtypePtr] = true
a.rtypes.SetHasher(a.hasher)
a.reflectZeros.SetHasher(a.hasher)
}
if runtime := a.prog.ImportedPackage("runtime"); runtime != nil {
a.runtimeSetFinalizer = runtime.Func("SetFinalizer")
}
a.computeTrackBits()
a.generate()
a.showCounts()
if optRenumber {
a.renumber()
}
N := len(a.nodes) // excludes solver-created nodes
if optHVN {
if debugHVNCrossCheck {
// Cross-check: run the solver once without
// optimization, once with, and compare the
// solutions.
savedConstraints := a.constraints
a.solve()
a.dumpSolution("A.pts", N)
// Restore.
a.constraints = savedConstraints
for _, n := range a.nodes {
n.solve = new(solverState)
}
a.nodes = a.nodes[:N]
// rtypes is effectively part of the solver state.
a.rtypes = typeutil.Map{}
a.rtypes.SetHasher(a.hasher)
}
a.hvn()
}
if debugHVNCrossCheck {
runtime.GC()
runtime.GC()
}
a.solve()
// Compare solutions.
if optHVN && debugHVNCrossCheck {
a.dumpSolution("B.pts", N)
if !diff("A.pts", "B.pts") {
return nil, fmt.Errorf("internal error: optimization changed solution")
}
}
// Create callgraph.Nodes in deterministic order.
if cg := a.result.CallGraph; cg != nil {
for _, caller := range a.cgnodes {
cg.CreateNode(caller.fn)
}
}
// Add dynamic edges to call graph.
var space [100]int
for _, caller := range a.cgnodes {
for _, site := range caller.sites {
for _, callee := range a.nodes[site.targets].solve.pts.AppendTo(space[:0]) {
a.callEdge(caller, site, nodeid(callee))
}
}
}
return a.result, nil
}
func (fr *frame) instruction(instr ssa.Instruction) {
fr.logf("[%T] %v @ %s\n", instr, instr, fr.pkg.Prog.Fset.Position(instr.Pos()))
if fr.GenerateDebug {
fr.debug.SetLocation(fr.builder, instr.Pos())
}
switch instr := instr.(type) {
case *ssa.Alloc:
typ := deref(instr.Type())
llvmtyp := fr.llvmtypes.ToLLVM(typ)
var value llvm.Value
if !instr.Heap {
value = fr.env[instr].value
fr.memsetZero(value, llvm.SizeOf(llvmtyp))
} else if fr.isInit && fr.shouldStaticallyAllocate(instr) {
// If this is the init function and we think it may be beneficial,
// allocate memory statically in the object file rather than on the
// heap. This allows us to optimize constant stores into such
// variables as static initializations.
global := llvm.AddGlobal(fr.module.Module, llvmtyp, "")
global.SetLinkage(llvm.InternalLinkage)
fr.addGlobal(global, typ)
ptr := llvm.ConstBitCast(global, llvm.PointerType(llvm.Int8Type(), 0))
fr.env[instr] = newValue(ptr, instr.Type())
} else {
value = fr.createTypeMalloc(typ)
value.SetName(instr.Comment)
value = fr.builder.CreateBitCast(value, llvm.PointerType(llvm.Int8Type(), 0), "")
fr.env[instr] = newValue(value, instr.Type())
}
case *ssa.BinOp:
lhs, rhs := fr.value(instr.X), fr.value(instr.Y)
fr.env[instr] = fr.binaryOp(lhs, instr.Op, rhs)
case *ssa.Call:
tuple := fr.callInstruction(instr)
if len(tuple) == 1 {
fr.env[instr] = tuple[0]
} else {
fr.tuples[instr] = tuple
}
case *ssa.ChangeInterface:
x := fr.value(instr.X)
// The source type must be a non-empty interface,
// as ChangeInterface cannot fail (E2I may fail).
if instr.Type().Underlying().(*types.Interface).NumMethods() > 0 {
x = fr.changeInterface(x, instr.Type(), false)
} else {
x = fr.convertI2E(x)
}
fr.env[instr] = x
case *ssa.ChangeType:
value := fr.llvmvalue(instr.X)
if _, ok := instr.Type().Underlying().(*types.Pointer); ok {
value = fr.builder.CreateBitCast(value, fr.llvmtypes.ToLLVM(instr.Type()), "")
}
fr.env[instr] = newValue(value, instr.Type())
case *ssa.Convert:
v := fr.value(instr.X)
fr.env[instr] = fr.convert(v, instr.Type())
case *ssa.Defer:
fn, arg := fr.createThunk(instr)
fr.runtime.Defer.call(fr, fr.frameptr, fn, arg)
case *ssa.Extract:
var elem llvm.Value
if t, ok := fr.tuples[instr.Tuple]; ok {
elem = t[instr.Index].value
} else {
tuple := fr.llvmvalue(instr.Tuple)
elem = fr.builder.CreateExtractValue(tuple, instr.Index, instr.Name())
}
elemtyp := instr.Type()
fr.env[instr] = newValue(elem, elemtyp)
case *ssa.Field:
fieldtyp := instr.Type()
if p, ok := fr.ptr[instr.X]; ok {
field := fr.builder.CreateStructGEP(p, instr.Field, instr.Name())
if fr.canAvoidElementLoad(instr) {
fr.ptr[instr] = field
} else {
fr.env[instr] = newValue(fr.builder.CreateLoad(field, ""), fieldtyp)
}
} else {
value := fr.llvmvalue(instr.X)
field := fr.builder.CreateExtractValue(value, instr.Field, instr.Name())
fr.env[instr] = newValue(field, fieldtyp)
}
case *ssa.FieldAddr:
ptr := fr.llvmvalue(instr.X)
fr.nilCheck(instr.X, ptr)
xtyp := instr.X.Type().Underlying().(*types.Pointer).Elem()
ptrtyp := llvm.PointerType(fr.llvmtypes.ToLLVM(xtyp), 0)
ptr = fr.builder.CreateBitCast(ptr, ptrtyp, "")
fieldptr := fr.builder.CreateStructGEP(ptr, instr.Field, instr.Name())
fieldptr = fr.builder.CreateBitCast(fieldptr, llvm.PointerType(llvm.Int8Type(), 0), "")
fieldptrtyp := instr.Type()
fr.env[instr] = newValue(fieldptr, fieldptrtyp)
case *ssa.Go:
fn, arg := fr.createThunk(instr)
fr.runtime.Go.call(fr, fn, arg)
case *ssa.If:
cond := fr.llvmvalue(instr.Cond)
block := instr.Block()
trueBlock := fr.block(block.Succs[0])
falseBlock := fr.block(block.Succs[1])
cond = fr.builder.CreateTrunc(cond, llvm.Int1Type(), "")
fr.builder.CreateCondBr(cond, trueBlock, falseBlock)
case *ssa.Index:
var arrayptr llvm.Value
if ptr, ok := fr.ptr[instr.X]; ok {
arrayptr = ptr
} else {
array := fr.llvmvalue(instr.X)
arrayptr = fr.allocaBuilder.CreateAlloca(array.Type(), "")
fr.builder.CreateStore(array, arrayptr)
}
index := fr.llvmvalue(instr.Index)
arraytyp := instr.X.Type().Underlying().(*types.Array)
arraylen := llvm.ConstInt(fr.llvmtypes.inttype, uint64(arraytyp.Len()), false)
// The index may not have been promoted to int (for example, if it
// came from a composite literal).
index = fr.createZExtOrTrunc(index, fr.types.inttype, "")
// Bounds checking: 0 <= index < len
zero := llvm.ConstNull(fr.types.inttype)
i0 := fr.builder.CreateICmp(llvm.IntSLT, index, zero, "")
li := fr.builder.CreateICmp(llvm.IntSLE, arraylen, index, "")
cond := fr.builder.CreateOr(i0, li, "")
fr.condBrRuntimeError(cond, gccgoRuntimeErrorARRAY_INDEX_OUT_OF_BOUNDS)
addr := fr.builder.CreateGEP(arrayptr, []llvm.Value{zero, index}, "")
if fr.canAvoidElementLoad(instr) {
fr.ptr[instr] = addr
} else {
fr.env[instr] = newValue(fr.builder.CreateLoad(addr, ""), instr.Type())
}
case *ssa.IndexAddr:
x := fr.llvmvalue(instr.X)
index := fr.llvmvalue(instr.Index)
var arrayptr, arraylen llvm.Value
var elemtyp types.Type
var errcode uint64
switch typ := instr.X.Type().Underlying().(type) {
case *types.Slice:
elemtyp = typ.Elem()
arrayptr = fr.builder.CreateExtractValue(x, 0, "")
arraylen = fr.builder.CreateExtractValue(x, 1, "")
errcode = gccgoRuntimeErrorSLICE_INDEX_OUT_OF_BOUNDS
case *types.Pointer: // *array
arraytyp := typ.Elem().Underlying().(*types.Array)
elemtyp = arraytyp.Elem()
fr.nilCheck(instr.X, x)
arrayptr = x
arraylen = llvm.ConstInt(fr.llvmtypes.inttype, uint64(arraytyp.Len()), false)
errcode = gccgoRuntimeErrorARRAY_INDEX_OUT_OF_BOUNDS
}
// The index may not have been promoted to int (for example, if it
// came from a composite literal).
index = fr.createZExtOrTrunc(index, fr.types.inttype, "")
// Bounds checking: 0 <= index < len
zero := llvm.ConstNull(fr.types.inttype)
i0 := fr.builder.CreateICmp(llvm.IntSLT, index, zero, "")
li := fr.builder.CreateICmp(llvm.IntSLE, arraylen, index, "")
cond := fr.builder.CreateOr(i0, li, "")
fr.condBrRuntimeError(cond, errcode)
ptrtyp := llvm.PointerType(fr.llvmtypes.ToLLVM(elemtyp), 0)
arrayptr = fr.builder.CreateBitCast(arrayptr, ptrtyp, "")
addr := fr.builder.CreateGEP(arrayptr, []llvm.Value{index}, "")
addr = fr.builder.CreateBitCast(addr, llvm.PointerType(llvm.Int8Type(), 0), "")
fr.env[instr] = newValue(addr, types.NewPointer(elemtyp))
case *ssa.Jump:
succ := instr.Block().Succs[0]
fr.builder.CreateBr(fr.block(succ))
case *ssa.Lookup:
x := fr.value(instr.X)
index := fr.value(instr.Index)
if isString(x.Type().Underlying()) {
fr.env[instr] = fr.stringIndex(x, index)
} else {
v, ok := fr.mapLookup(x, index)
if instr.CommaOk {
fr.tuples[instr] = []*govalue{v, ok}
} else {
fr.env[instr] = v
}
}
case *ssa.MakeChan:
fr.env[instr] = fr.makeChan(instr.Type(), fr.value(instr.Size))
case *ssa.MakeClosure:
llfn := fr.resolveFunctionGlobal(instr.Fn.(*ssa.Function))
llfn = llvm.ConstBitCast(llfn, llvm.PointerType(llvm.Int8Type(), 0))
fn := newValue(llfn, instr.Fn.(*ssa.Function).Signature)
bindings := make([]*govalue, len(instr.Bindings))
for i, binding := range instr.Bindings {
bindings[i] = fr.value(binding)
}
fr.env[instr] = fr.makeClosure(fn, bindings)
case *ssa.MakeInterface:
// fr.ptr[instr.X] will be set if a pointer load was elided by canAvoidLoad
if ptr, ok := fr.ptr[instr.X]; ok {
fr.env[instr] = fr.makeInterfaceFromPointer(ptr, instr.X.Type(), instr.Type())
} else {
receiver := fr.llvmvalue(instr.X)
fr.env[instr] = fr.makeInterface(receiver, instr.X.Type(), instr.Type())
}
case *ssa.MakeMap:
fr.env[instr] = fr.makeMap(instr.Type(), fr.value(instr.Reserve))
case *ssa.MakeSlice:
length := fr.value(instr.Len)
capacity := fr.value(instr.Cap)
fr.env[instr] = fr.makeSlice(instr.Type(), length, capacity)
case *ssa.MapUpdate:
m := fr.value(instr.Map)
k := fr.value(instr.Key)
v := fr.value(instr.Value)
fr.mapUpdate(m, k, v)
case *ssa.Next:
iter := fr.tuples[instr.Iter]
if instr.IsString {
fr.tuples[instr] = fr.stringIterNext(iter)
} else {
fr.tuples[instr] = fr.mapIterNext(iter)
}
case *ssa.Panic:
arg := fr.value(instr.X)
fr.callPanic(arg, true)
case *ssa.Phi:
typ := instr.Type()
phi := fr.builder.CreatePHI(fr.llvmtypes.ToLLVM(typ), instr.Comment)
fr.env[instr] = newValue(phi, typ)
fr.phis = append(fr.phis, pendingPhi{instr, phi})
case *ssa.Range:
x := fr.value(instr.X)
switch x.Type().Underlying().(type) {
case *types.Map:
fr.tuples[instr] = fr.mapIterInit(x)
case *types.Basic: // string
fr.tuples[instr] = fr.stringIterInit(x)
default:
panic(fmt.Sprintf("unhandled range for type %T", x.Type()))
}
case *ssa.Return:
vals := make([]llvm.Value, len(instr.Results))
for i, res := range instr.Results {
vals[i] = fr.llvmvalue(res)
}
fr.retInf.encode(llvm.GlobalContext(), fr.allocaBuilder, fr.builder, vals)
case *ssa.RunDefers:
fr.runDefers()
case *ssa.Select:
index, recvOk, recvElems := fr.chanSelect(instr)
tuple := append([]*govalue{index, recvOk}, recvElems...)
fr.tuples[instr] = tuple
case *ssa.Send:
fr.chanSend(fr.value(instr.Chan), fr.value(instr.X))
case *ssa.Slice:
x := fr.llvmvalue(instr.X)
low := fr.llvmvalue(instr.Low)
high := fr.llvmvalue(instr.High)
max := fr.llvmvalue(instr.Max)
slice := fr.slice(x, instr.X.Type(), low, high, max)
fr.env[instr] = newValue(slice, instr.Type())
case *ssa.Store:
addr := fr.llvmvalue(instr.Addr)
value := fr.llvmvalue(instr.Val)
addr = fr.builder.CreateBitCast(addr, llvm.PointerType(value.Type(), 0), "")
// If this is the init function, see if we can simulate the effect
// of the store in a global's initializer, in which case we can avoid
// generating code for it.
if !fr.isInit || !fr.maybeStoreInInitializer(value, addr) {
fr.nilCheck(instr.Addr, addr)
fr.builder.CreateStore(value, addr)
}
case *switchInstr:
fr.emitSwitch(instr)
case *ssa.TypeAssert:
x := fr.value(instr.X)
if instr.CommaOk {
v, ok := fr.interfaceTypeCheck(x, instr.AssertedType)
fr.tuples[instr] = []*govalue{v, ok}
} else {
fr.env[instr] = fr.interfaceTypeAssert(x, instr.AssertedType)
}
case *ssa.UnOp:
operand := fr.value(instr.X)
switch instr.Op {
case token.ARROW:
x, ok := fr.chanRecv(operand, instr.CommaOk)
if instr.CommaOk {
fr.tuples[instr] = []*govalue{x, ok}
} else {
fr.env[instr] = x
}
case token.MUL:
fr.nilCheck(instr.X, operand.value)
if !fr.canAvoidLoad(instr, operand.value) {
// The bitcast is necessary to handle recursive pointer loads.
llptr := fr.builder.CreateBitCast(operand.value, llvm.PointerType(fr.llvmtypes.ToLLVM(instr.Type()), 0), "")
fr.env[instr] = newValue(fr.builder.CreateLoad(llptr, ""), instr.Type())
}
default:
fr.env[instr] = fr.unaryOp(operand, instr.Op)
}
default:
panic(fmt.Sprintf("unhandled: %v", instr))
}
}
// TODO(adonovan):
// - test use of explicit hasher across two maps.
// - test hashcodes are consistent with equals for a range of types
// (e.g. all types generated by type-checking some body of real code).
import (
"testing"
"llvm.org/llgo/third_party/gotools/go/types"
"llvm.org/llgo/third_party/gotools/go/types/typeutil"
)
var (
tStr = types.Typ[types.String] // string
tPStr1 = types.NewPointer(tStr) // *string
tPStr2 = types.NewPointer(tStr) // *string, again
tInt = types.Typ[types.Int] // int
tChanInt1 = types.NewChan(types.RecvOnly, tInt) // <-chan int
tChanInt2 = types.NewChan(types.RecvOnly, tInt) // <-chan int, again
)
func checkEqualButNotIdentical(t *testing.T, x, y types.Type, comment string) {
if !types.Identical(x, y) {
t.Errorf("%s: not equal: %s, %s", comment, x, y)
}
if x == y {
t.Errorf("%s: identical: %v, %v", comment, x, y)
}
}
// Precondition: T is not a method signature (*Signature with Recv()!=nil).
// Recursive case: skip => don't create methods for T.
//
// EXCLUSIVE_LOCKS_REQUIRED(prog.methodsMu)
//
func (prog *Program) needMethods(T types.Type, skip bool) {
// Each package maintains its own set of types it has visited.
if prevSkip, ok := prog.runtimeTypes.At(T).(bool); ok {
// needMethods(T) was previously called
if !prevSkip || skip {
return // already seen, with same or false 'skip' value
}
}
prog.runtimeTypes.Set(T, skip)
tmset := prog.MethodSets.MethodSet(T)
if !skip && !isInterface(T) && tmset.Len() > 0 {
// Create methods of T.
mset := prog.createMethodSet(T)
if !mset.complete {
mset.complete = true
n := tmset.Len()
for i := 0; i < n; i++ {
prog.addMethod(mset, tmset.At(i))
}
}
}
// Recursion over signatures of each method.
for i := 0; i < tmset.Len(); i++ {
sig := tmset.At(i).Type().(*types.Signature)
prog.needMethods(sig.Params(), false)
prog.needMethods(sig.Results(), false)
}
switch t := T.(type) {
case *types.Basic:
// nop
case *types.Interface:
// nop---handled by recursion over method set.
case *types.Pointer:
prog.needMethods(t.Elem(), false)
case *types.Slice:
prog.needMethods(t.Elem(), false)
case *types.Chan:
prog.needMethods(t.Elem(), false)
case *types.Map:
prog.needMethods(t.Key(), false)
prog.needMethods(t.Elem(), false)
case *types.Signature:
if t.Recv() != nil {
panic(fmt.Sprintf("Signature %s has Recv %s", t, t.Recv()))
}
prog.needMethods(t.Params(), false)
prog.needMethods(t.Results(), false)
case *types.Named:
// A pointer-to-named type can be derived from a named
// type via reflection. It may have methods too.
prog.needMethods(types.NewPointer(T), false)
// Consider 'type T struct{S}' where S has methods.
// Reflection provides no way to get from T to struct{S},
// only to S, so the method set of struct{S} is unwanted,
// so set 'skip' flag during recursion.
prog.needMethods(t.Underlying(), true)
case *types.Array:
prog.needMethods(t.Elem(), false)
case *types.Struct:
for i, n := 0, t.NumFields(); i < n; i++ {
prog.needMethods(t.Field(i).Type(), false)
}
case *types.Tuple:
for i, n := 0, t.Len(); i < n; i++ {
prog.needMethods(t.At(i).Type(), false)
}
default:
panic(T)
}
}
// CreatePackage constructs and returns an SSA Package from an
// error-free package described by info, and populates its Members
// mapping.
//
// Repeated calls with the same info return the same Package.
//
// The real work of building SSA form for each function is not done
// until a subsequent call to Package.Build().
//
func (prog *Program) CreatePackage(info *loader.PackageInfo) *Package {
if p := prog.packages[info.Pkg]; p != nil {
return p // already loaded
}
p := &Package{
Prog: prog,
Members: make(map[string]Member),
values: make(map[types.Object]Value),
Object: info.Pkg,
info: info, // transient (CREATE and BUILD phases)
}
// Add init() function.
p.init = &Function{
name: "init",
Signature: new(types.Signature),
Synthetic: "package initializer",
Pkg: p,
Prog: prog,
}
p.Members[p.init.name] = p.init
// CREATE phase.
// Allocate all package members: vars, funcs, consts and types.
if len(info.Files) > 0 {
// Go source package.
for _, file := range info.Files {
for _, decl := range file.Decls {
membersFromDecl(p, decl)
}
}
} else {
// GC-compiled binary package.
// No code.
// No position information.
scope := p.Object.Scope()
for _, name := range scope.Names() {
obj := scope.Lookup(name)
memberFromObject(p, obj, nil)
if obj, ok := obj.(*types.TypeName); ok {
named := obj.Type().(*types.Named)
for i, n := 0, named.NumMethods(); i < n; i++ {
memberFromObject(p, named.Method(i), nil)
}
}
}
}
if prog.mode&BareInits == 0 {
// Add initializer guard variable.
initguard := &Global{
Pkg: p,
name: "init$guard",
typ: types.NewPointer(tBool),
}
p.Members[initguard.Name()] = initguard
}
if prog.mode&GlobalDebug != 0 {
p.SetDebugMode(true)
}
if prog.mode&PrintPackages != 0 {
printMu.Lock()
p.WriteTo(os.Stdout)
printMu.Unlock()
}
if info.Importable {
prog.imported[info.Pkg.Path()] = p
}
prog.packages[p.Object] = p
return p
}