// chanOps returns a slice of all the channel operations in the instruction.
// Derived from cmd/guru/peers.go.
func chanOps(instr ssa.Instruction) []chanOp {
fn := instr.Parent()
var ops []chanOp
switch instr := instr.(type) {
case *ssa.UnOp:
if instr.Op == token.ARROW {
// TODO(adonovan): don't assume <-ch; could be 'range ch'.
ops = append(ops, chanOp{instr.X, "received", instr.Pos(), len("<-"), fn})
}
case *ssa.Send:
ops = append(ops, chanOp{instr.Chan, "sent", instr.Pos(), len("<-"), fn})
case *ssa.Select:
for _, st := range instr.States {
mode := "received"
if st.Dir == types.SendOnly {
mode = "sent"
}
ops = append(ops, chanOp{st.Chan, mode, st.Pos, len("<-"), fn})
}
case ssa.CallInstruction:
call := instr.Common()
if blt, ok := call.Value.(*ssa.Builtin); ok && blt.Name() == "close" {
pos := instr.Common().Pos()
ops = append(ops, chanOp{call.Args[0], "closed", pos - token.Pos(len("close")), len("close("), fn})
}
}
return ops
}
// chanOps extract all channel operations from an instruction.
func chanOps(instr ssa.Instruction) []ChanOp {
var ops []ChanOp
switch instr := instr.(type) {
case *ssa.Send:
ops = append(ops, ChanOp{instr.Chan, ChanSend, instr.Pos()})
case *ssa.UnOp:
if instr.Op == token.ARROW {
ops = append(ops, ChanOp{instr.X, ChanRecv, instr.Pos()})
}
case *ssa.Select:
for _, st := range instr.States {
switch st.Dir {
case types.SendOnly:
ops = append(ops, ChanOp{st.Chan, ChanSend, st.Pos})
case types.RecvOnly:
ops = append(ops, ChanOp{st.Chan, ChanRecv, st.Pos})
}
}
case ssa.CallInstruction:
common := instr.Common()
if b, ok := common.Value.(*ssa.Builtin); ok && b.Name() == "close" {
ops = append(ops, ChanOp{common.Args[0], ChanClose, common.Pos()})
}
}
return ops
}
// chanOps returns a slice of all the channel operations in the instruction.
func chanOps(instr ssa.Instruction) []chanOp {
// TODO(adonovan): handle calls to reflect.{Select,Recv,Send,Close} too.
var ops []chanOp
switch instr := instr.(type) {
case *ssa.UnOp:
if instr.Op == token.ARROW {
ops = append(ops, chanOp{instr.X, types.RecvOnly, instr.Pos()})
}
case *ssa.Send:
ops = append(ops, chanOp{instr.Chan, types.SendOnly, instr.Pos()})
case *ssa.Select:
for _, st := range instr.States {
ops = append(ops, chanOp{st.Chan, st.Dir, st.Pos})
}
case ssa.CallInstruction:
cc := instr.Common()
if b, ok := cc.Value.(*ssa.Builtin); ok && b.Name() == "close" {
ops = append(ops, chanOp{cc.Args[0], types.SendRecv, cc.Pos()})
}
}
return ops
}