diff options
| -rw-r--r-- | prog/analysis.go | 46 |
1 files changed, 27 insertions, 19 deletions
diff --git a/prog/analysis.go b/prog/analysis.go index bb57ec463..3da9cba01 100644 --- a/prog/analysis.go +++ b/prog/analysis.go @@ -9,9 +9,6 @@ package prog import ( - "bytes" - "crypto/sha1" - "encoding/binary" "fmt" ) @@ -206,10 +203,11 @@ func (p *Prog) FallbackSignal(info []CallInfo) { }) // Specifically look only at top-level arguments, // deeper arguments can produce too much false signal. - flags := new(bytes.Buffer) + flags := 0 for _, arg := range c.Args { switch a := arg.(type) { case *ResultArg: + flags <<= 1 if a.Res != nil { ctor := resources[a.Res] if ctor != nil { @@ -217,35 +215,45 @@ func (p *Prog) FallbackSignal(info []CallInfo) { encodeFallbackSignal(fallbackSignalCtor, id, ctor.Meta.ID)) } } else { - for _, v := range a.Type().(*ResourceType).SpecialValues() { - if a.Val == v { - binary.Write(flags, binary.LittleEndian, v) - } + if a.Val != a.Type().(*ResourceType).SpecialValues()[0] { + flags |= 1 } } case *ConstArg: + const width = 3 + flags <<= width switch typ := a.Type().(type) { case *FlagsType: - var mask uint64 - for _, v := range typ.Vals { - mask |= v + if typ.BitMask { + for i, v := range typ.Vals { + if a.Val&v != 0 { + flags ^= 1 << (uint(i) % width) + } + } + } else { + for i, v := range typ.Vals { + if a.Val == v { + flags |= i % (1 << width) + break + } + } } - binary.Write(flags, binary.LittleEndian, a.Val&mask) case *LenType: + flags <<= 1 if a.Val == 0 { - flags.WriteByte(0x42) + flags |= 1 } } case *PointerArg: + flags <<= 1 if a.IsNull() { - flags.WriteByte(0x43) + flags |= 1 } } - if flags.Len() != 0 { - hash := sha1.Sum(flags.Bytes()) - inf.Signal = append(inf.Signal, - encodeFallbackSignal(fallbackSignalFlags, id, int(hash[0]))) - } + } + if flags != 0 { + inf.Signal = append(inf.Signal, + encodeFallbackSignal(fallbackSignalFlags, id, flags)) } } } |