go_agent/src/code.google.com/p/go.tools/pointer/reflect.go
package pointer
// This file implements the generation and resolution rules for
// constraints arising from the use of reflection in the target
// program. See doc.go for explanation of the representation.
//
// For consistency, the names of all parameters match those of the
// actual functions in the "reflect" package.
//
// To avoid proliferation of equivalent labels, instrinsics should
// memoize as much as possible, like TypeOf and Zero do for their
// tagged objects.
//
// TODO(adonovan): all {} functions are TODO.
//
// TODO(adonovan): this file is rather subtle. Explain how we derive
// the implementation of each reflect operator from its spec,
// including the subtleties of reflect.flag{Addr,RO,Indir}.
// [Hint: our implementation is as if reflect.flagIndir was always
// true, i.e. reflect.Values are pointers to tagged objects, there is
// no inline allocation optimization; and indirect tagged objects (not
// yet implemented) correspond to reflect.Values with
// reflect.flagAddr.]
// A picture would help too.
import (
"fmt"
"go/ast"
"reflect"
"code.google.com/p/go.tools/go/exact"
"code.google.com/p/go.tools/go/types"
"code.google.com/p/go.tools/ssa"
)
// -------------------- (reflect.Value) --------------------
func ext۰reflect۰Value۰Addr(a *analysis, cgn *cgnode) {}
// ---------- func (Value).Bytes() Value ----------
// result = v.Bytes()
type rVBytesConstraint struct {
v nodeid // (ptr)
result nodeid
}
func (c *rVBytesConstraint) String() string {
return fmt.Sprintf("n%d = reflect n%d.Bytes()", c.result, c.v)
}
func (c *rVBytesConstraint) ptr() nodeid {
return c.v
}
func (c *rVBytesConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for vObj := range delta {
tDyn, slice, indirect := a.taggedValue(vObj)
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
tSlice, ok := tDyn.Underlying().(*types.Slice)
if ok && types.IsIdentical(tSlice.Elem(), types.Typ[types.Uint8]) {
if a.onlineCopy(c.result, slice) {
changed = true
}
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰Value۰Bytes(a *analysis, cgn *cgnode) {
a.addConstraint(&rVBytesConstraint{
v: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func (Value).Call(in []Value) []Value ----------
// result = v.Call(in)
type rVCallConstraint struct {
cgn *cgnode
targets nodeid
v nodeid // (ptr)
arg nodeid // = in[*]
result nodeid
dotdotdot bool // interpret last arg as a "..." slice
}
func (c *rVCallConstraint) String() string {
return fmt.Sprintf("n%d = reflect n%d.Call(n%d)", c.result, c.v, c.arg)
}
func (c *rVCallConstraint) ptr() nodeid {
return c.v
}
func (c *rVCallConstraint) solve(a *analysis, _ *node, delta nodeset) {
if c.targets == 0 {
panic("no targets")
}
changed := false
for vObj := range delta {
tDyn, fn, indirect := a.taggedValue(vObj)
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
tSig, ok := tDyn.Underlying().(*types.Signature)
if !ok {
continue // not a function
}
if tSig.Recv() != nil {
panic(tSig) // TODO(adonovan): rethink when we implement Method()
}
// Add dynamic call target.
if a.onlineCopy(c.targets, fn) {
a.addWork(c.targets)
// TODO(adonovan): is 'else continue' a sound optimisation here?
}
// Allocate a P/R block.
tParams := tSig.Params()
tResults := tSig.Results()
params := a.addNodes(tParams, "rVCall.params")
results := a.addNodes(tResults, "rVCall.results")
// Make a dynamic call to 'fn'.
a.store(fn, params, 1, a.sizeof(tParams))
a.load(results, fn, 1+a.sizeof(tParams), a.sizeof(tResults))
// Populate P by type-asserting each actual arg (all merged in c.arg).
for i, n := 0, tParams.Len(); i < n; i++ {
T := tParams.At(i).Type()
a.typeAssert(T, params, c.arg, false)
params += nodeid(a.sizeof(T))
}
// Use R by tagging and copying each actual result to c.result.
for i, n := 0, tResults.Len(); i < n; i++ {
T := tResults.At(i).Type()
// Convert from an arbitrary type to a reflect.Value
// (like MakeInterface followed by reflect.ValueOf).
if isInterface(T) {
// (don't tag)
if a.onlineCopy(c.result, results) {
changed = true
}
} else {
obj := a.makeTagged(T, c.cgn, nil)
a.onlineCopyN(obj+1, results, a.sizeof(T))
if a.addLabel(c.result, obj) { // (true)
changed = true
}
}
results += nodeid(a.sizeof(T))
}
}
if changed {
a.addWork(c.result)
}
}
// Common code for direct (inlined) and indirect calls to (reflect.Value).Call.
func reflectCallImpl(a *analysis, cgn *cgnode, site *callsite, recv, arg nodeid, dotdotdot bool) nodeid {
// Allocate []reflect.Value array for the result.
ret := a.nextNode()
a.addNodes(types.NewArray(a.reflectValueObj.Type(), 1), "rVCall.ret")
a.endObject(ret, cgn, nil)
// pts(targets) will be the set of possible call targets.
site.targets = a.addOneNode(tInvalid, "rvCall.targets", nil)
// All arguments are merged since they arrive in a slice.
argelts := a.addOneNode(a.reflectValueObj.Type(), "rVCall.args", nil)
a.load(argelts, arg, 1, 1) // slice elements
a.addConstraint(&rVCallConstraint{
cgn: cgn,
targets: site.targets,
v: recv,
arg: argelts,
result: ret + 1, // results go into elements of ret
dotdotdot: dotdotdot,
})
return ret
}
func reflectCall(a *analysis, cgn *cgnode, dotdotdot bool) {
// This is the shared contour implementation of (reflect.Value).Call
// and CallSlice, as used by indirect calls (rare).
// Direct calls are inlined in gen.go, eliding the
// intermediate cgnode for Call.
site := new(callsite)
cgn.sites = append(cgn.sites, site)
recv := a.funcParams(cgn.obj)
arg := recv + 1
ret := reflectCallImpl(a, cgn, site, recv, arg, dotdotdot)
a.addressOf(a.funcResults(cgn.obj), ret)
}
func ext۰reflect۰Value۰Call(a *analysis, cgn *cgnode) {
reflectCall(a, cgn, false)
}
func ext۰reflect۰Value۰CallSlice(a *analysis, cgn *cgnode) {
// TODO(adonovan): implement. Also, inline direct calls in gen.go too.
if false {
reflectCall(a, cgn, true)
}
}
func ext۰reflect۰Value۰Convert(a *analysis, cgn *cgnode) {}
// ---------- func (Value).Elem() Value ----------
// result = v.Elem()
type rVElemConstraint struct {
cgn *cgnode
v nodeid // (ptr)
result nodeid
}
func (c *rVElemConstraint) String() string {
return fmt.Sprintf("n%d = reflect n%d.Elem()", c.result, c.v)
}
func (c *rVElemConstraint) ptr() nodeid {
return c.v
}
func (c *rVElemConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for vObj := range delta {
tDyn, payload, indirect := a.taggedValue(vObj)
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
switch t := tDyn.Underlying().(type) {
case *types.Interface:
if a.onlineCopy(c.result, payload) {
changed = true
}
case *types.Pointer:
obj := a.makeTagged(t.Elem(), c.cgn, nil)
a.load(obj+1, payload, 0, a.sizeof(t.Elem()))
if a.addLabel(c.result, obj) {
changed = true
}
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰Value۰Elem(a *analysis, cgn *cgnode) {
a.addConstraint(&rVElemConstraint{
cgn: cgn,
v: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
func ext۰reflect۰Value۰Field(a *analysis, cgn *cgnode) {}
func ext۰reflect۰Value۰FieldByIndex(a *analysis, cgn *cgnode) {}
func ext۰reflect۰Value۰FieldByName(a *analysis, cgn *cgnode) {}
func ext۰reflect۰Value۰FieldByNameFunc(a *analysis, cgn *cgnode) {}
// ---------- func (Value).Index() Value ----------
// result = v.Index()
type rVIndexConstraint struct {
cgn *cgnode
v nodeid // (ptr)
result nodeid
}
func (c *rVIndexConstraint) String() string {
return fmt.Sprintf("n%d = reflect n%d.Index()", c.result, c.v)
}
func (c *rVIndexConstraint) ptr() nodeid {
return c.v
}
func (c *rVIndexConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for vObj := range delta {
tDyn, payload, indirect := a.taggedValue(vObj)
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
var res nodeid
switch t := tDyn.Underlying().(type) {
case *types.Array:
res = a.makeTagged(t.Elem(), c.cgn, nil)
a.onlineCopyN(res+1, payload+1, a.sizeof(t.Elem()))
case *types.Slice:
res = a.makeTagged(t.Elem(), c.cgn, nil)
a.load(res+1, payload, 1, a.sizeof(t.Elem()))
case *types.Basic:
if t.Kind() == types.String {
res = a.makeTagged(types.Typ[types.Rune], c.cgn, nil)
}
}
if res != 0 && a.addLabel(c.result, res) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰Value۰Index(a *analysis, cgn *cgnode) {
a.addConstraint(&rVIndexConstraint{
cgn: cgn,
v: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func (Value).Interface() Value ----------
// result = v.Interface()
type rVInterfaceConstraint struct {
v nodeid // (ptr)
result nodeid
}
func (c *rVInterfaceConstraint) String() string {
return fmt.Sprintf("n%d = reflect n%d.Interface()", c.result, c.v)
}
func (c *rVInterfaceConstraint) ptr() nodeid {
return c.v
}
func (c *rVInterfaceConstraint) solve(a *analysis, _ *node, delta nodeset) {
resultPts := &a.nodes[c.result].pts
changed := false
for vObj := range delta {
tDyn, payload, indirect := a.taggedValue(vObj)
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
if isInterface(tDyn) {
if a.onlineCopy(c.result, payload) {
a.addWork(c.result)
}
} else {
if resultPts.add(vObj) {
changed = true
}
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰Value۰Interface(a *analysis, cgn *cgnode) {
a.addConstraint(&rVInterfaceConstraint{
v: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func (Value).MapIndex(Value) Value ----------
// result = v.MapIndex(_)
type rVMapIndexConstraint struct {
cgn *cgnode
v nodeid // (ptr)
result nodeid
}
func (c *rVMapIndexConstraint) String() string {
return fmt.Sprintf("n%d = reflect n%d.MapIndex(_)", c.result, c.v)
}
func (c *rVMapIndexConstraint) ptr() nodeid {
return c.v
}
func (c *rVMapIndexConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for vObj := range delta {
tDyn, m, indirect := a.taggedValue(vObj)
tMap, _ := tDyn.Underlying().(*types.Map)
if tMap == nil {
continue // not a map
}
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
obj := a.makeTagged(tMap.Elem(), c.cgn, nil)
a.load(obj+1, m, a.sizeof(tMap.Key()), a.sizeof(tMap.Elem()))
if a.addLabel(c.result, obj) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰Value۰MapIndex(a *analysis, cgn *cgnode) {
a.addConstraint(&rVMapIndexConstraint{
cgn: cgn,
v: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func (Value).MapKeys() []Value ----------
// result = v.MapKeys()
type rVMapKeysConstraint struct {
cgn *cgnode
v nodeid // (ptr)
result nodeid
}
func (c *rVMapKeysConstraint) String() string {
return fmt.Sprintf("n%d = reflect n%d.MapKeys()", c.result, c.v)
}
func (c *rVMapKeysConstraint) ptr() nodeid {
return c.v
}
func (c *rVMapKeysConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for vObj := range delta {
tDyn, m, indirect := a.taggedValue(vObj)
tMap, _ := tDyn.Underlying().(*types.Map)
if tMap == nil {
continue // not a map
}
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
kObj := a.makeTagged(tMap.Key(), c.cgn, nil)
a.load(kObj+1, m, 0, a.sizeof(tMap.Key()))
if a.addLabel(c.result, kObj) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰Value۰MapKeys(a *analysis, cgn *cgnode) {
// Allocate an array for the result.
obj := a.nextNode()
a.addNodes(types.NewArray(a.reflectValueObj.Type(), 1), "reflect.MapKeys result")
a.endObject(obj, cgn, nil)
a.addressOf(a.funcResults(cgn.obj), obj)
a.addConstraint(&rVMapKeysConstraint{
cgn: cgn,
v: a.funcParams(cgn.obj),
result: obj + 1, // result is stored in array elems
})
}
func ext۰reflect۰Value۰Method(a *analysis, cgn *cgnode) {}
func ext۰reflect۰Value۰MethodByName(a *analysis, cgn *cgnode) {}
// ---------- func (Value).Recv(Value) ----------
// result, _ = v.Recv()
type rVRecvConstraint struct {
cgn *cgnode
v nodeid // (ptr)
result nodeid
}
func (c *rVRecvConstraint) String() string {
return fmt.Sprintf("n%d = reflect n%d.Recv()", c.result, c.v)
}
func (c *rVRecvConstraint) ptr() nodeid {
return c.v
}
func (c *rVRecvConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for vObj := range delta {
tDyn, ch, indirect := a.taggedValue(vObj)
tChan, _ := tDyn.Underlying().(*types.Chan)
if tChan == nil {
continue // not a channel
}
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
tElem := tChan.Elem()
elemObj := a.makeTagged(tElem, c.cgn, nil)
a.load(elemObj+1, ch, 0, a.sizeof(tElem))
if a.addLabel(c.result, elemObj) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰Value۰Recv(a *analysis, cgn *cgnode) {
a.addConstraint(&rVRecvConstraint{
cgn: cgn,
v: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func (Value).Send(Value) ----------
// v.Send(x)
type rVSendConstraint struct {
cgn *cgnode
v nodeid // (ptr)
x nodeid
}
func (c *rVSendConstraint) String() string {
return fmt.Sprintf("reflect n%d.Send(n%d)", c.v, c.x)
}
func (c *rVSendConstraint) ptr() nodeid {
return c.v
}
func (c *rVSendConstraint) solve(a *analysis, _ *node, delta nodeset) {
for vObj := range delta {
tDyn, ch, indirect := a.taggedValue(vObj)
tChan, _ := tDyn.Underlying().(*types.Chan)
if tChan == nil {
continue // not a channel
}
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
// Extract x's payload to xtmp, then store to channel.
tElem := tChan.Elem()
xtmp := a.addNodes(tElem, "Send.xtmp")
a.typeAssert(tElem, xtmp, c.x, false)
a.store(ch, xtmp, 0, a.sizeof(tElem))
}
}
func ext۰reflect۰Value۰Send(a *analysis, cgn *cgnode) {
params := a.funcParams(cgn.obj)
a.addConstraint(&rVSendConstraint{
cgn: cgn,
v: params,
x: params + 1,
})
}
func ext۰reflect۰Value۰Set(a *analysis, cgn *cgnode) {}
// ---------- func (Value).SetBytes(x []byte) ----------
// v.SetBytes(x)
type rVSetBytesConstraint struct {
cgn *cgnode
v nodeid // (ptr)
x nodeid
}
func (c *rVSetBytesConstraint) String() string {
return fmt.Sprintf("reflect n%d.SetBytes(n%d)", c.v, c.x)
}
func (c *rVSetBytesConstraint) ptr() nodeid {
return c.v
}
func (c *rVSetBytesConstraint) solve(a *analysis, _ *node, delta nodeset) {
for vObj := range delta {
tDyn, slice, indirect := a.taggedValue(vObj)
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
tSlice, ok := tDyn.Underlying().(*types.Slice)
if ok && types.IsIdentical(tSlice.Elem(), types.Typ[types.Uint8]) {
if a.onlineCopy(slice, c.x) {
a.addWork(slice)
}
}
}
}
func ext۰reflect۰Value۰SetBytes(a *analysis, cgn *cgnode) {
params := a.funcParams(cgn.obj)
a.addConstraint(&rVSetBytesConstraint{
cgn: cgn,
v: params,
x: params + 1,
})
}
// ---------- func (Value).SetMapIndex(k Value, v Value) ----------
// v.SetMapIndex(key, val)
type rVSetMapIndexConstraint struct {
cgn *cgnode
v nodeid // (ptr)
key nodeid
val nodeid
}
func (c *rVSetMapIndexConstraint) String() string {
return fmt.Sprintf("reflect n%d.SetMapIndex(n%d, n%d)", c.v, c.key, c.val)
}
func (c *rVSetMapIndexConstraint) ptr() nodeid {
return c.v
}
func (c *rVSetMapIndexConstraint) solve(a *analysis, _ *node, delta nodeset) {
for vObj := range delta {
tDyn, m, indirect := a.taggedValue(vObj)
tMap, _ := tDyn.Underlying().(*types.Map)
if tMap == nil {
continue // not a map
}
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
keysize := a.sizeof(tMap.Key())
// Extract key's payload to keytmp, then store to map key.
keytmp := a.addNodes(tMap.Key(), "SetMapIndex.keytmp")
a.typeAssert(tMap.Key(), keytmp, c.key, false)
a.store(m, keytmp, 0, keysize)
// Extract val's payload to vtmp, then store to map value.
valtmp := a.addNodes(tMap.Elem(), "SetMapIndex.valtmp")
a.typeAssert(tMap.Elem(), valtmp, c.val, false)
a.store(m, valtmp, keysize, a.sizeof(tMap.Elem()))
}
}
func ext۰reflect۰Value۰SetMapIndex(a *analysis, cgn *cgnode) {
params := a.funcParams(cgn.obj)
a.addConstraint(&rVSetMapIndexConstraint{
cgn: cgn,
v: params,
key: params + 1,
val: params + 2,
})
}
func ext۰reflect۰Value۰SetPointer(a *analysis, cgn *cgnode) {}
// ---------- func (Value).Slice(v Value, i, j int) ----------
// result = v.Slice(_, _)
type rVSliceConstraint struct {
cgn *cgnode
v nodeid // (ptr)
result nodeid
}
func (c *rVSliceConstraint) String() string {
return fmt.Sprintf("n%d = reflect n%d.Slice(_, _)", c.result, c.v)
}
func (c *rVSliceConstraint) ptr() nodeid {
return c.v
}
func (c *rVSliceConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for vObj := range delta {
tDyn, payload, indirect := a.taggedValue(vObj)
if indirect {
// TODO(adonovan): we'll need to implement this
// when we start creating indirect tagged objects.
panic("indirect tagged object")
}
var res nodeid
switch t := tDyn.Underlying().(type) {
case *types.Pointer:
if tArr, ok := t.Elem().Underlying().(*types.Array); ok {
// pointer to array
res = a.makeTagged(types.NewSlice(tArr.Elem()), c.cgn, nil)
if a.onlineCopy(res+1, payload) {
a.addWork(res + 1)
}
}
case *types.Array:
// TODO(adonovan): implement addressable
// arrays when we do indirect tagged objects.
case *types.Slice:
res = vObj
case *types.Basic:
if t == types.Typ[types.String] {
res = vObj
}
}
if res != 0 && a.addLabel(c.result, res) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰Value۰Slice(a *analysis, cgn *cgnode) {
a.addConstraint(&rVSliceConstraint{
cgn: cgn,
v: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// -------------------- Standalone reflect functions --------------------
func ext۰reflect۰Append(a *analysis, cgn *cgnode) {}
func ext۰reflect۰AppendSlice(a *analysis, cgn *cgnode) {}
func ext۰reflect۰Copy(a *analysis, cgn *cgnode) {}
// ---------- func ChanOf(ChanDir, Type) Type ----------
// result = ChanOf(dir, t)
type reflectChanOfConstraint struct {
cgn *cgnode
t nodeid // (ptr)
result nodeid
dirs []ast.ChanDir
}
func (c *reflectChanOfConstraint) String() string {
return fmt.Sprintf("n%d = reflect.ChanOf(n%d)", c.result, c.t)
}
func (c *reflectChanOfConstraint) ptr() nodeid {
return c.t
}
func (c *reflectChanOfConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for tObj := range delta {
T := a.rtypeTaggedValue(tObj)
for _, dir := range c.dirs {
if a.addLabel(c.result, a.makeRtype(types.NewChan(dir, T))) {
changed = true
}
}
}
if changed {
a.addWork(c.result)
}
}
// dirMap maps reflect.ChanDir to the set of channel types generated by ChanOf.
var dirMap = [...][]ast.ChanDir{
0: {ast.RECV, ast.SEND, ast.RECV | ast.SEND}, // unknown
reflect.RecvDir: {ast.RECV},
reflect.SendDir: {ast.SEND},
reflect.BothDir: {ast.RECV | ast.SEND},
}
func ext۰reflect۰ChanOf(a *analysis, cgn *cgnode) {
// If we have access to the callsite,
// and the channel argument is a constant (as is usual),
// only generate the requested direction.
var dir reflect.ChanDir // unknown
if site := cgn.callersite; site != nil {
if c, ok := site.instr.Common().Args[0].(*ssa.Const); ok {
v, _ := exact.Int64Val(c.Value)
if 0 <= v && v <= int64(reflect.BothDir) {
dir = reflect.ChanDir(v)
}
}
}
params := a.funcParams(cgn.obj)
a.addConstraint(&reflectChanOfConstraint{
cgn: cgn,
t: params + 1,
result: a.funcResults(cgn.obj),
dirs: dirMap[dir],
})
}
// ---------- func Indirect(v Value) Value ----------
// result = Indirect(v)
type reflectIndirectConstraint struct {
cgn *cgnode
v nodeid // (ptr)
result nodeid
}
func (c *reflectIndirectConstraint) String() string {
return fmt.Sprintf("n%d = reflect.Indirect(n%d)", c.result, c.v)
}
func (c *reflectIndirectConstraint) ptr() nodeid {
return c.v
}
func (c *reflectIndirectConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for vObj := range delta {
tDyn, _, _ := a.taggedValue(vObj)
var res nodeid
if tPtr, ok := tDyn.Underlying().(*types.Pointer); ok {
// load the payload of the pointer's tagged object
// into a new tagged object
res = a.makeTagged(tPtr.Elem(), c.cgn, nil)
a.load(res+1, vObj+1, 0, a.sizeof(tPtr.Elem()))
} else {
res = vObj
}
if a.addLabel(c.result, res) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰Indirect(a *analysis, cgn *cgnode) {
a.addConstraint(&reflectIndirectConstraint{
cgn: cgn,
v: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func MakeChan(Type) Value ----------
// result = MakeChan(typ)
type reflectMakeChanConstraint struct {
cgn *cgnode
typ nodeid // (ptr)
result nodeid
}
func (c *reflectMakeChanConstraint) String() string {
return fmt.Sprintf("n%d = reflect.MakeChan(n%d)", c.result, c.typ)
}
func (c *reflectMakeChanConstraint) ptr() nodeid {
return c.typ
}
func (c *reflectMakeChanConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for typObj := range delta {
T := a.rtypeTaggedValue(typObj)
tChan, ok := T.Underlying().(*types.Chan)
if !ok || tChan.Dir() != ast.SEND|ast.RECV {
continue // not a bidirectional channel type
}
obj := a.nextNode()
a.addNodes(tChan.Elem(), "reflect.MakeChan.value")
a.endObject(obj, c.cgn, nil)
// put its address in a new T-tagged object
id := a.makeTagged(T, c.cgn, nil)
a.addLabel(id+1, obj)
// flow the T-tagged object to the result
if a.addLabel(c.result, id) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰MakeChan(a *analysis, cgn *cgnode) {
a.addConstraint(&reflectMakeChanConstraint{
cgn: cgn,
typ: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
func ext۰reflect۰MakeFunc(a *analysis, cgn *cgnode) {}
// ---------- func MakeMap(Type) Value ----------
// result = MakeMap(typ)
type reflectMakeMapConstraint struct {
cgn *cgnode
typ nodeid // (ptr)
result nodeid
}
func (c *reflectMakeMapConstraint) String() string {
return fmt.Sprintf("n%d = reflect.MakeMap(n%d)", c.result, c.typ)
}
func (c *reflectMakeMapConstraint) ptr() nodeid {
return c.typ
}
func (c *reflectMakeMapConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for typObj := range delta {
T := a.rtypeTaggedValue(typObj)
tMap, ok := T.Underlying().(*types.Map)
if !ok {
continue // not a map type
}
mapObj := a.nextNode()
a.addNodes(tMap.Key(), "reflect.MakeMap.key")
a.addNodes(tMap.Elem(), "reflect.MakeMap.value")
a.endObject(mapObj, c.cgn, nil)
// put its address in a new T-tagged object
id := a.makeTagged(T, c.cgn, nil)
a.addLabel(id+1, mapObj)
// flow the T-tagged object to the result
if a.addLabel(c.result, id) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰MakeMap(a *analysis, cgn *cgnode) {
a.addConstraint(&reflectMakeMapConstraint{
cgn: cgn,
typ: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func MakeSlice(Type) Value ----------
// result = MakeSlice(typ)
type reflectMakeSliceConstraint struct {
cgn *cgnode
typ nodeid // (ptr)
result nodeid
}
func (c *reflectMakeSliceConstraint) String() string {
return fmt.Sprintf("n%d = reflect.MakeSlice(n%d)", c.result, c.typ)
}
func (c *reflectMakeSliceConstraint) ptr() nodeid {
return c.typ
}
func (c *reflectMakeSliceConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for typObj := range delta {
T := a.rtypeTaggedValue(typObj)
if _, ok := T.Underlying().(*types.Slice); !ok {
continue // not a slice type
}
obj := a.nextNode()
a.addNodes(sliceToArray(T), "reflect.MakeSlice")
a.endObject(obj, c.cgn, nil)
// put its address in a new T-tagged object
id := a.makeTagged(T, c.cgn, nil)
a.addLabel(id+1, obj)
// flow the T-tagged object to the result
if a.addLabel(c.result, id) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰MakeSlice(a *analysis, cgn *cgnode) {
a.addConstraint(&reflectMakeSliceConstraint{
cgn: cgn,
typ: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
func ext۰reflect۰MapOf(a *analysis, cgn *cgnode) {}
// ---------- func New(Type) Value ----------
// result = New(typ)
type reflectNewConstraint struct {
cgn *cgnode
typ nodeid // (ptr)
result nodeid
}
func (c *reflectNewConstraint) String() string {
return fmt.Sprintf("n%d = reflect.New(n%d)", c.result, c.typ)
}
func (c *reflectNewConstraint) ptr() nodeid {
return c.typ
}
func (c *reflectNewConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for typObj := range delta {
T := a.rtypeTaggedValue(typObj)
// allocate new T object
newObj := a.nextNode()
a.addNodes(T, "reflect.New")
a.endObject(newObj, c.cgn, nil)
// put its address in a new *T-tagged object
id := a.makeTagged(types.NewPointer(T), c.cgn, nil)
a.addLabel(id+1, newObj)
// flow the pointer to the result
if a.addLabel(c.result, id) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰New(a *analysis, cgn *cgnode) {
a.addConstraint(&reflectNewConstraint{
cgn: cgn,
typ: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
func ext۰reflect۰NewAt(a *analysis, cgn *cgnode) {
ext۰reflect۰New(a, cgn)
// TODO(adonovan): also report dynamic calls to unsound intrinsics.
if site := cgn.callersite; site != nil {
a.warnf(site.pos(), "unsound: %s contains a reflect.NewAt() call", site.instr.Parent())
}
}
// ---------- func PtrTo(Type) Type ----------
// result = PtrTo(t)
type reflectPtrToConstraint struct {
cgn *cgnode
t nodeid // (ptr)
result nodeid
}
func (c *reflectPtrToConstraint) String() string {
return fmt.Sprintf("n%d = reflect.PtrTo(n%d)", c.result, c.t)
}
func (c *reflectPtrToConstraint) ptr() nodeid {
return c.t
}
func (c *reflectPtrToConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for tObj := range delta {
T := a.rtypeTaggedValue(tObj)
if a.addLabel(c.result, a.makeRtype(types.NewPointer(T))) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰PtrTo(a *analysis, cgn *cgnode) {
a.addConstraint(&reflectPtrToConstraint{
cgn: cgn,
t: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
func ext۰reflect۰Select(a *analysis, cgn *cgnode) {}
// ---------- func SliceOf(Type) Type ----------
// result = SliceOf(t)
type reflectSliceOfConstraint struct {
cgn *cgnode
t nodeid // (ptr)
result nodeid
}
func (c *reflectSliceOfConstraint) String() string {
return fmt.Sprintf("n%d = reflect.SliceOf(n%d)", c.result, c.t)
}
func (c *reflectSliceOfConstraint) ptr() nodeid {
return c.t
}
func (c *reflectSliceOfConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for tObj := range delta {
T := a.rtypeTaggedValue(tObj)
if a.addLabel(c.result, a.makeRtype(types.NewSlice(T))) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰SliceOf(a *analysis, cgn *cgnode) {
a.addConstraint(&reflectSliceOfConstraint{
cgn: cgn,
t: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func TypeOf(v Value) Type ----------
// result = TypeOf(i)
type reflectTypeOfConstraint struct {
cgn *cgnode
i nodeid // (ptr)
result nodeid
}
func (c *reflectTypeOfConstraint) String() string {
return fmt.Sprintf("n%d = reflect.TypeOf(n%d)", c.result, c.i)
}
func (c *reflectTypeOfConstraint) ptr() nodeid {
return c.i
}
func (c *reflectTypeOfConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for iObj := range delta {
tDyn, _, _ := a.taggedValue(iObj)
if a.addLabel(c.result, a.makeRtype(tDyn)) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰TypeOf(a *analysis, cgn *cgnode) {
a.addConstraint(&reflectTypeOfConstraint{
cgn: cgn,
i: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func ValueOf(interface{}) Value ----------
func ext۰reflect۰ValueOf(a *analysis, cgn *cgnode) {
// TODO(adonovan): when we start creating indirect tagged
// objects, we'll need to handle them specially here since
// they must never appear in the PTS of an interface{}.
a.copy(a.funcResults(cgn.obj), a.funcParams(cgn.obj), 1)
}
// ---------- func Zero(Type) Value ----------
// result = Zero(typ)
type reflectZeroConstraint struct {
cgn *cgnode
typ nodeid // (ptr)
result nodeid
}
func (c *reflectZeroConstraint) String() string {
return fmt.Sprintf("n%d = reflect.Zero(n%d)", c.result, c.typ)
}
func (c *reflectZeroConstraint) ptr() nodeid {
return c.typ
}
func (c *reflectZeroConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for typObj := range delta {
T := a.rtypeTaggedValue(typObj)
// TODO(adonovan): if T is an interface type, we need
// to create an indirect tagged object containing
// new(T). To avoid updates of such shared values,
// we'll need another flag on indirect tagged objects
// that marks whether they are addressable or
// readonly, just like the reflect package does.
// memoize using a.reflectZeros[T]
var id nodeid
if z := a.reflectZeros.At(T); false && z != nil {
id = z.(nodeid)
} else {
id = a.makeTagged(T, c.cgn, nil)
a.reflectZeros.Set(T, id)
}
if a.addLabel(c.result, id) {
changed = true
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰Zero(a *analysis, cgn *cgnode) {
a.addConstraint(&reflectZeroConstraint{
cgn: cgn,
typ: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// -------------------- (*reflect.rtype) methods --------------------
// ---------- func (*rtype) Elem() Type ----------
// result = Elem(t)
type rtypeElemConstraint struct {
cgn *cgnode
t nodeid // (ptr)
result nodeid
}
func (c *rtypeElemConstraint) String() string {
return fmt.Sprintf("n%d = (*reflect.rtype).Elem(n%d)", c.result, c.t)
}
func (c *rtypeElemConstraint) ptr() nodeid {
return c.t
}
func (c *rtypeElemConstraint) solve(a *analysis, _ *node, delta nodeset) {
// Implemented by *types.{Map,Chan,Array,Slice,Pointer}.
type hasElem interface {
Elem() types.Type
}
changed := false
for tObj := range delta {
T := a.nodes[tObj].obj.data.(types.Type)
if tHasElem, ok := T.Underlying().(hasElem); ok {
if a.addLabel(c.result, a.makeRtype(tHasElem.Elem())) {
changed = true
}
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰rtype۰Elem(a *analysis, cgn *cgnode) {
a.addConstraint(&rtypeElemConstraint{
cgn: cgn,
t: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func (*rtype) Field(int) StructField ----------
// ---------- func (*rtype) FieldByName(string) (StructField, bool) ----------
// result = FieldByName(t, name)
// result = Field(t, _)
type rtypeFieldByNameConstraint struct {
cgn *cgnode
name string // name of field; "" for unknown
t nodeid // (ptr)
result nodeid
}
func (c *rtypeFieldByNameConstraint) String() string {
return fmt.Sprintf("n%d = (*reflect.rtype).FieldByName(n%d, %q)", c.result, c.t, c.name)
}
func (c *rtypeFieldByNameConstraint) ptr() nodeid {
return c.t
}
func (c *rtypeFieldByNameConstraint) solve(a *analysis, _ *node, delta nodeset) {
// type StructField struct {
// 0 __identity__
// 1 Name string
// 2 PkgPath string
// 3 Type Type
// 4 Tag StructTag
// 5 Offset uintptr
// 6 Index []int
// 7 Anonymous bool
// }
for tObj := range delta {
T := a.nodes[tObj].obj.data.(types.Type)
tStruct, ok := T.Underlying().(*types.Struct)
if !ok {
continue // not a struct type
}
n := tStruct.NumFields()
for i := 0; i < n; i++ {
f := tStruct.Field(i)
if c.name == "" || c.name == f.Name() {
// a.offsetOf(Type) is 3.
if id := c.result + 3; a.addLabel(id, a.makeRtype(f.Type())) {
a.addWork(id)
}
// TODO(adonovan): StructField.Index should be non-nil.
}
}
}
}
func ext۰reflect۰rtype۰FieldByName(a *analysis, cgn *cgnode) {
// If we have access to the callsite,
// and the argument is a string constant,
// return only that field.
var name string
if site := cgn.callersite; site != nil {
if c, ok := site.instr.Common().Args[0].(*ssa.Const); ok {
name = exact.StringVal(c.Value)
}
}
a.addConstraint(&rtypeFieldByNameConstraint{
cgn: cgn,
name: name,
t: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
func ext۰reflect۰rtype۰Field(a *analysis, cgn *cgnode) {
// No-one ever calls Field with a constant argument,
// so we don't specialize that case.
a.addConstraint(&rtypeFieldByNameConstraint{
cgn: cgn,
t: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
func ext۰reflect۰rtype۰FieldByIndex(a *analysis, cgn *cgnode) {}
func ext۰reflect۰rtype۰FieldByNameFunc(a *analysis, cgn *cgnode) {}
// ---------- func (*rtype) In/Out(i int) Type ----------
// result = In/Out(t, i)
type rtypeInOutConstraint struct {
cgn *cgnode
t nodeid // (ptr)
result nodeid
out bool
i int // -ve if not a constant
}
func (c *rtypeInOutConstraint) String() string {
return fmt.Sprintf("n%d = (*reflect.rtype).InOut(n%d, %d)", c.result, c.t, c.i)
}
func (c *rtypeInOutConstraint) ptr() nodeid {
return c.t
}
func (c *rtypeInOutConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for tObj := range delta {
T := a.nodes[tObj].obj.data.(types.Type)
sig, ok := T.Underlying().(*types.Signature)
if !ok {
continue // not a func type
}
tuple := sig.Params()
if c.out {
tuple = sig.Results()
}
for i, n := 0, tuple.Len(); i < n; i++ {
if c.i < 0 || c.i == i {
if a.addLabel(c.result, a.makeRtype(tuple.At(i).Type())) {
changed = true
}
}
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰rtype۰InOut(a *analysis, cgn *cgnode, out bool) {
// If we have access to the callsite,
// and the argument is an int constant,
// return only that parameter.
index := -1
if site := cgn.callersite; site != nil {
if c, ok := site.instr.Common().Args[0].(*ssa.Const); ok {
v, _ := exact.Int64Val(c.Value)
index = int(v)
}
}
a.addConstraint(&rtypeInOutConstraint{
cgn: cgn,
t: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
out: out,
i: index,
})
}
func ext۰reflect۰rtype۰In(a *analysis, cgn *cgnode) {
ext۰reflect۰rtype۰InOut(a, cgn, false)
}
func ext۰reflect۰rtype۰Out(a *analysis, cgn *cgnode) {
ext۰reflect۰rtype۰InOut(a, cgn, true)
}
// ---------- func (*rtype) Key() Type ----------
// result = Key(t)
type rtypeKeyConstraint struct {
cgn *cgnode
t nodeid // (ptr)
result nodeid
}
func (c *rtypeKeyConstraint) String() string {
return fmt.Sprintf("n%d = (*reflect.rtype).Key(n%d)", c.result, c.t)
}
func (c *rtypeKeyConstraint) ptr() nodeid {
return c.t
}
func (c *rtypeKeyConstraint) solve(a *analysis, _ *node, delta nodeset) {
changed := false
for tObj := range delta {
T := a.nodes[tObj].obj.data.(types.Type)
if tMap, ok := T.Underlying().(*types.Map); ok {
if a.addLabel(c.result, a.makeRtype(tMap.Key())) {
changed = true
}
}
}
if changed {
a.addWork(c.result)
}
}
func ext۰reflect۰rtype۰Key(a *analysis, cgn *cgnode) {
a.addConstraint(&rtypeKeyConstraint{
cgn: cgn,
t: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
// ---------- func (*rtype) Method(int) (Method, bool) ----------
// ---------- func (*rtype) MethodByName(string) (Method, bool) ----------
// result = MethodByName(t, name)
// result = Method(t, _)
type rtypeMethodByNameConstraint struct {
cgn *cgnode
name string // name of method; "" for unknown
t nodeid // (ptr)
result nodeid
}
func (c *rtypeMethodByNameConstraint) String() string {
return fmt.Sprintf("n%d = (*reflect.rtype).MethodByName(n%d, %q)", c.result, c.t, c.name)
}
func (c *rtypeMethodByNameConstraint) ptr() nodeid {
return c.t
}
// changeRecv returns sig with Recv prepended to Params().
func changeRecv(sig *types.Signature) *types.Signature {
params := sig.Params()
n := params.Len()
p2 := make([]*types.Var, n+1)
p2[0] = sig.Recv()
for i := 0; i < n; i++ {
p2[i+1] = params.At(i)
}
return types.NewSignature(nil, nil, types.NewTuple(p2...), sig.Results(), sig.IsVariadic())
}
func (c *rtypeMethodByNameConstraint) solve(a *analysis, _ *node, delta nodeset) {
for tObj := range delta {
T := a.nodes[tObj].obj.data.(types.Type)
// We don't use Lookup(c.name) when c.name != "" to avoid
// ambiguity: >1 unexported methods could match.
mset := T.MethodSet()
for i, n := 0, mset.Len(); i < n; i++ {
sel := mset.At(i)
if c.name == "" || c.name == sel.Obj().Name() {
// type Method struct {
// 0 __identity__
// 1 Name string
// 2 PkgPath string
// 3 Type Type
// 4 Func Value
// 5 Index int
// }
fn := a.prog.Method(sel)
// a.offsetOf(Type) is 3.
if id := c.result + 3; a.addLabel(id, a.makeRtype(changeRecv(fn.Signature))) {
a.addWork(id)
}
// a.offsetOf(Func) is 4.
if id := c.result + 4; a.addLabel(id, a.objectNode(nil, fn)) {
a.addWork(id)
}
}
}
}
}
func ext۰reflect۰rtype۰MethodByName(a *analysis, cgn *cgnode) {
// If we have access to the callsite,
// and the argument is a string constant,
// return only that method.
var name string
if site := cgn.callersite; site != nil {
if c, ok := site.instr.Common().Args[0].(*ssa.Const); ok {
name = exact.StringVal(c.Value)
}
}
a.addConstraint(&rtypeMethodByNameConstraint{
cgn: cgn,
name: name,
t: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}
func ext۰reflect۰rtype۰Method(a *analysis, cgn *cgnode) {
// No-one ever calls Method with a constant argument,
// so we don't specialize that case.
a.addConstraint(&rtypeMethodByNameConstraint{
cgn: cgn,
t: a.funcParams(cgn.obj),
result: a.funcResults(cgn.obj),
})
}