mirror of
https://github.com/golang/go
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exp/ssa: (#5 of 5): the SSA interpreter and 'ssadump' tool.
R=gri, iant CC=golang-dev https://golang.org/cl/7226065
This commit is contained in:
Alan Donovan
parent
0a9f1ab8bb
commit
c8f2449ea7
312
src/pkg/exp/ssa/interp/external.go
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312
src/pkg/exp/ssa/interp/external.go
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@ -0,0 +1,312 @@
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package interp
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// Emulated functions that we cannot interpret because they are
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// external or because they use "unsafe" or "reflect" operations.
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import (
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"exp/ssa"
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"math"
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"os"
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"runtime"
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"syscall"
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"time"
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)
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type externalFn func(fn *ssa.Function, args []value, slots []value) value
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// Key strings are from Function.FullName().
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// That little dot ۰ is an Arabic zero numeral (U+06F0), categories [Nd].
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var externals = map[string]externalFn{
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"(reflect.Value).CanAddr": ext۰reflect۰Value۰CanAddr,
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"(reflect.Value).CanInterface": ext۰reflect۰Value۰CanInterface,
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"(reflect.Value).Elem": ext۰reflect۰Value۰Elem,
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"(reflect.Value).Field": ext۰reflect۰Value۰Field,
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"(reflect.Value).Index": ext۰reflect۰Value۰Index,
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"(reflect.Value).Int": ext۰reflect۰Value۰Int,
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"(reflect.Value).Interface": ext۰reflect۰Value۰Interface,
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"(reflect.Value).IsNil": ext۰reflect۰Value۰IsNil,
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"(reflect.Value).IsValid": ext۰reflect۰Value۰IsValid,
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"(reflect.Value).Kind": ext۰reflect۰Value۰Kind,
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"(reflect.Value).Len": ext۰reflect۰Value۰Len,
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"(reflect.Value).NumField": ext۰reflect۰Value۰NumField,
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"(reflect.Value).Pointer": ext۰reflect۰Value۰Pointer,
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"(reflect.Value).Type": ext۰reflect۰Value۰Type,
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"(reflect.rtype).Bits": ext۰reflect۰rtype۰Bits,
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"(reflect.rtype).Elem": ext۰reflect۰rtype۰Elem,
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"(reflect.rtype).Kind": ext۰reflect۰rtype۰Kind,
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"(reflect.rtype).String": ext۰reflect۰rtype۰String,
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"math.Float32bits": ext۰math۰Float32bits,
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"math.Float32frombits": ext۰math۰Float32frombits,
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"math.Float64bits": ext۰math۰Float64bits,
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"math.Float64frombits": ext۰math۰Float64frombits,
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"reflect.TypeOf": ext۰reflect۰TypeOf,
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"reflect.ValueOf": ext۰reflect۰ValueOf,
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"reflect.init": ext۰reflect۰Init,
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"reflect.valueInterface": ext۰reflect۰valueInterface,
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"runtime.Breakpoint": ext۰runtime۰Breakpoint,
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"runtime.GC": ext۰runtime۰GC,
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"runtime.GOMAXPROCS": ext۰runtime۰GOMAXPROCS,
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"runtime.Gosched": ext۰runtime۰Gosched,
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"runtime.ReadMemStats": ext۰runtime۰ReadMemStats,
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"runtime.SetFinalizer": ext۰runtime۰SetFinalizer,
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"runtime.getgoroot": ext۰runtime۰getgoroot,
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"sync/atomic.AddInt32": ext۰atomic۰AddInt32,
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"sync/atomic.CompareAndSwapInt32": ext۰atomic۰CompareAndSwapInt32,
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"sync/atomic.LoadInt32": ext۰atomic۰LoadInt32,
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"sync/atomic.LoadUint32": ext۰atomic۰LoadUint32,
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"sync/atomic.StoreInt32": ext۰atomic۰StoreInt32,
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"sync/atomic.StoreUint32": ext۰atomic۰StoreUint32,
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"syscall.Exit": ext۰syscall۰Exit,
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"syscall.Getpid": ext۰syscall۰Getpid,
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"syscall.Kill": ext۰syscall۰Kill,
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"syscall.Write": ext۰syscall۰Write,
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"time.Sleep": ext۰time۰Sleep,
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"time.now": ext۰time۰now,
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}
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func ext۰math۰Float64frombits(fn *ssa.Function, args []value, slots []value) value {
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return math.Float64frombits(args[0].(uint64))
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}
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func ext۰math۰Float64bits(fn *ssa.Function, args []value, slots []value) value {
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return math.Float64bits(args[0].(float64))
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}
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func ext۰math۰Float32frombits(fn *ssa.Function, args []value, slots []value) value {
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return math.Float32frombits(args[0].(uint32))
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}
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func ext۰math۰Float32bits(fn *ssa.Function, args []value, slots []value) value {
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return math.Float32bits(args[0].(float32))
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}
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func ext۰runtime۰Breakpoint(fn *ssa.Function, args []value, slots []value) value {
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runtime.Breakpoint()
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return nil
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}
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func ext۰runtime۰getgoroot(fn *ssa.Function, args []value, slots []value) value {
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return os.Getenv("GOROOT")
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}
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func ext۰runtime۰GOMAXPROCS(fn *ssa.Function, args []value, slots []value) value {
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return runtime.GOMAXPROCS(args[0].(int))
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}
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func ext۰runtime۰GC(fn *ssa.Function, args []value, slots []value) value {
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runtime.GC()
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return nil
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}
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func ext۰runtime۰Gosched(fn *ssa.Function, args []value, slots []value) value {
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runtime.Gosched()
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return nil
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}
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func ext۰runtime۰ReadMemStats(fn *ssa.Function, args []value, slots []value) value {
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// TODO(adonovan): populate args[0].(Struct)
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return nil
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}
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func ext۰atomic۰LoadUint32(fn *ssa.Function, args []value, slots []value) value {
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// TODO(adonovan): fix: not atomic!
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return (*args[0].(*value)).(uint32)
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}
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func ext۰atomic۰StoreUint32(fn *ssa.Function, args []value, slots []value) value {
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// TODO(adonovan): fix: not atomic!
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*args[0].(*value) = args[1].(uint32)
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return nil
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}
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func ext۰atomic۰LoadInt32(fn *ssa.Function, args []value, slots []value) value {
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// TODO(adonovan): fix: not atomic!
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return (*args[0].(*value)).(int32)
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}
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func ext۰atomic۰StoreInt32(fn *ssa.Function, args []value, slots []value) value {
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// TODO(adonovan): fix: not atomic!
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*args[0].(*value) = args[1].(int32)
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return nil
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}
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func ext۰atomic۰CompareAndSwapInt32(fn *ssa.Function, args []value, slots []value) value {
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// TODO(adonovan): fix: not atomic!
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p := args[0].(*value)
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if (*p).(int32) == args[1].(int32) {
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*p = args[2].(int32)
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return true
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}
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return false
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}
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func ext۰atomic۰AddInt32(fn *ssa.Function, args []value, slots []value) value {
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// TODO(adonovan): fix: not atomic!
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p := args[0].(*value)
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newv := (*p).(int32) + args[1].(int32)
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*p = newv
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return newv
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}
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func ext۰runtime۰SetFinalizer(fn *ssa.Function, args []value, slots []value) value {
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return nil // ignore
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}
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func ext۰time۰now(fn *ssa.Function, args []value, slots []value) value {
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nano := time.Now().UnixNano()
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return tuple{int64(nano / 1e9), int32(nano % 1e9)}
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}
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func ext۰time۰Sleep(fn *ssa.Function, args []value, slots []value) value {
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time.Sleep(time.Duration(args[0].(int64)))
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return nil
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}
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func ext۰syscall۰Exit(fn *ssa.Function, args []value, slots []value) value {
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// We could emulate syscall.Syscall but it's more effort.
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syscall.Exit(args[0].(int))
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return nil
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}
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func ext۰syscall۰Getpid(fn *ssa.Function, args []value, slots []value) value {
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// We could emulate syscall.Syscall but it's more effort.
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return syscall.Getpid()
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}
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func ext۰syscall۰Kill(fn *ssa.Function, args []value, slots []value) value {
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// We could emulate syscall.Syscall but it's more effort.
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err := syscall.Kill(args[0].(int), syscall.Signal(args[1].(int)))
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err = err // TODO(adonovan): fix: adapt concrete err to interpreted iface (e.g. call interpreted errors.New)
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return iface{}
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}
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func ext۰syscall۰Write(fn *ssa.Function, args []value, slots []value) value {
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// We could emulate syscall.Syscall but it's more effort.
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p := args[1].([]value)
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b := make([]byte, 0, len(p))
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for i := range p {
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b = append(b, p[i].(byte))
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}
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n, _ := syscall.Write(args[0].(int), b)
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err := iface{} // TODO(adonovan): fix: adapt concrete err to interpreted iface.
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return tuple{n, err}
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}
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// The set of remaining native functions we need to implement (as needed):
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// bytes/bytes.go:42:func Equal(a, b []byte) bool
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// bytes/bytes_decl.go:8:func IndexByte(s []byte, c byte) int // asm_$GOARCH.s
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// crypto/aes/cipher_asm.go:10:func hasAsm() bool
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// crypto/aes/cipher_asm.go:11:func encryptBlockAsm(nr int, xk *uint32, dst, src *byte)
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// crypto/aes/cipher_asm.go:12:func decryptBlockAsm(nr int, xk *uint32, dst, src *byte)
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// crypto/aes/cipher_asm.go:13:func expandKeyAsm(nr int, key *byte, enc *uint32, dec *uint32)
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// hash/crc32/crc32_amd64.go:12:func haveSSE42() bool
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// hash/crc32/crc32_amd64.go:16:func castagnoliSSE42(crc uint32, p []byte) uint32
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// math/abs.go:12:func Abs(x float64) float64
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// math/asin.go:19:func Asin(x float64) float64
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// math/asin.go:51:func Acos(x float64) float64
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// math/atan.go:95:func Atan(x float64) float64
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// math/atan2.go:29:func Atan2(y, x float64) float64
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// math/big/arith_decl.go:8:func mulWW(x, y Word) (z1, z0 Word)
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// math/big/arith_decl.go:9:func divWW(x1, x0, y Word) (q, r Word)
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// math/big/arith_decl.go:10:func addVV(z, x, y []Word) (c Word)
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// math/big/arith_decl.go:11:func subVV(z, x, y []Word) (c Word)
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// math/big/arith_decl.go:12:func addVW(z, x []Word, y Word) (c Word)
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// math/big/arith_decl.go:13:func subVW(z, x []Word, y Word) (c Word)
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// math/big/arith_decl.go:14:func shlVU(z, x []Word, s uint) (c Word)
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// math/big/arith_decl.go:15:func shrVU(z, x []Word, s uint) (c Word)
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// math/big/arith_decl.go:16:func mulAddVWW(z, x []Word, y, r Word) (c Word)
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// math/big/arith_decl.go:17:func addMulVVW(z, x []Word, y Word) (c Word)
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// math/big/arith_decl.go:18:func divWVW(z []Word, xn Word, x []Word, y Word) (r Word)
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// math/big/arith_decl.go:19:func bitLen(x Word) (n int)
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// math/dim.go:13:func Dim(x, y float64) float64
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// math/dim.go:26:func Max(x, y float64) float64
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// math/dim.go:53:func Min(x, y float64) float64
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// math/exp.go:14:func Exp(x float64) float64
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// math/exp.go:135:func Exp2(x float64) float64
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// math/expm1.go:124:func Expm1(x float64) float64
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// math/floor.go:13:func Floor(x float64) float64
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// math/floor.go:36:func Ceil(x float64) float64
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// math/floor.go:48:func Trunc(x float64) float64
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// math/frexp.go:16:func Frexp(f float64) (frac float64, exp int)
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// math/hypot.go:17:func Hypot(p, q float64) float64
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// math/ldexp.go:14:func Ldexp(frac float64, exp int) float64
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// math/log.go:80:func Log(x float64) float64
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// math/log10.go:9:func Log10(x float64) float64
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// math/log10.go:17:func Log2(x float64) float64
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// math/log1p.go:95:func Log1p(x float64) float64
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// math/mod.go:21:func Mod(x, y float64) float64
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// math/modf.go:13:func Modf(f float64) (int float64, frac float64)
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// math/remainder.go:37:func Remainder(x, y float64) float64
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// math/sin.go:117:func Cos(x float64) float64
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// math/sin.go:174:func Sin(x float64) float64
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// math/sincos.go:15:func Sincos(x float64) (sin, cos float64)
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// math/sqrt.go:14:func Sqrt(x float64) float64
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// math/tan.go:82:func Tan(x float64) float64
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// os/file_posix.go:14:func sigpipe() // implemented in package runtime
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// os/signal/signal_unix.go:15:func signal_enable(uint32)
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// os/signal/signal_unix.go:16:func signal_recv() uint32
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// runtime/debug.go:13:func LockOSThread()
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// runtime/debug.go:17:func UnlockOSThread()
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// runtime/debug.go:27:func NumCPU() int
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// runtime/debug.go:30:func NumCgoCall() int64
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// runtime/debug.go:33:func NumGoroutine() int
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// runtime/debug.go:90:func MemProfile(p []MemProfileRecord, inuseZero bool) (n int, ok bool)
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// runtime/debug.go:114:func ThreadCreateProfile(p []StackRecord) (n int, ok bool)
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// runtime/debug.go:122:func GoroutineProfile(p []StackRecord) (n int, ok bool)
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// runtime/debug.go:132:func CPUProfile() []byte
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// runtime/debug.go:141:func SetCPUProfileRate(hz int)
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// runtime/debug.go:149:func SetBlockProfileRate(rate int)
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// runtime/debug.go:166:func BlockProfile(p []BlockProfileRecord) (n int, ok bool)
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// runtime/debug.go:172:func Stack(buf []byte, all bool) int
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// runtime/error.go:81:func typestring(interface{}) string
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// runtime/extern.go:19:func Goexit()
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// runtime/extern.go:27:func Caller(skip int) (pc uintptr, file string, line int, ok bool)
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// runtime/extern.go:34:func Callers(skip int, pc []uintptr) int
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// runtime/extern.go:51:func FuncForPC(pc uintptr) *Func
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// runtime/extern.go:68:func funcline_go(*Func, uintptr) (string, int)
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// runtime/extern.go:71:func mid() uint32
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// runtime/pprof/pprof.go:667:func runtime_cyclesPerSecond() int64
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// runtime/race.go:16:func RaceDisable()
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// runtime/race.go:19:func RaceEnable()
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// runtime/race.go:21:func RaceAcquire(addr unsafe.Pointer)
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// runtime/race.go:22:func RaceRelease(addr unsafe.Pointer)
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// runtime/race.go:23:func RaceReleaseMerge(addr unsafe.Pointer)
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// runtime/race.go:25:func RaceRead(addr unsafe.Pointer)
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// runtime/race.go:26:func RaceWrite(addr unsafe.Pointer)
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// runtime/race.go:28:func RaceSemacquire(s *uint32)
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// runtime/race.go:29:func RaceSemrelease(s *uint32)
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// sync/atomic/doc.go:49:func CompareAndSwapInt64(addr *int64, old, new int64) (swapped bool)
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// sync/atomic/doc.go:52:func CompareAndSwapUint32(addr *uint32, old, new uint32) (swapped bool)
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// sync/atomic/doc.go:55:func CompareAndSwapUint64(addr *uint64, old, new uint64) (swapped bool)
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// sync/atomic/doc.go:58:func CompareAndSwapUintptr(addr *uintptr, old, new uintptr) (swapped bool)
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// sync/atomic/doc.go:61:func CompareAndSwapPointer(addr *unsafe.Pointer, old, new unsafe.Pointer) (swapped bool)
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// sync/atomic/doc.go:67:func AddUint32(addr *uint32, delta uint32) (new uint32)
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// sync/atomic/doc.go:70:func AddInt64(addr *int64, delta int64) (new int64)
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// sync/atomic/doc.go:73:func AddUint64(addr *uint64, delta uint64) (new uint64)
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// sync/atomic/doc.go:76:func AddUintptr(addr *uintptr, delta uintptr) (new uintptr)
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// sync/atomic/doc.go:82:func LoadInt64(addr *int64) (val int64)
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// sync/atomic/doc.go:88:func LoadUint64(addr *uint64) (val uint64)
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// sync/atomic/doc.go:91:func LoadUintptr(addr *uintptr) (val uintptr)
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// sync/atomic/doc.go:94:func LoadPointer(addr *unsafe.Pointer) (val unsafe.Pointer)
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// sync/atomic/doc.go:100:func StoreInt64(addr *int64, val int64)
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// sync/atomic/doc.go:106:func StoreUint64(addr *uint64, val uint64)
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// sync/atomic/doc.go:109:func StoreUintptr(addr *uintptr, val uintptr)
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// sync/atomic/doc.go:112:func StorePointer(addr *unsafe.Pointer, val unsafe.Pointer)
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// sync/runtime.go:12:func runtime_Semacquire(s *uint32)
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// sync/runtime.go:18:func runtime_Semrelease(s *uint32)
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// syscall/env_unix.go:30:func setenv_c(k, v string)
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// syscall/syscall_linux_amd64.go:60:func Gettimeofday(tv *Timeval) (err error)
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// syscall/syscall_linux_amd64.go:61:func Time(t *Time_t) (tt Time_t, err error)
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// syscall/syscall_linux_arm.go:28:func Seek(fd int, offset int64, whence int) (newoffset int64, err error)
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// syscall/syscall_unix.go:23:func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
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// syscall/syscall_unix.go:24:func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
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// syscall/syscall_unix.go:25:func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
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// syscall/syscall_unix.go:26:func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
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// time/sleep.go:25:func startTimer(*runtimeTimer)
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// time/sleep.go:26:func stopTimer(*runtimeTimer) bool
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// time/time.go:758:func now() (sec int64, nsec int32)
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// unsafe/unsafe.go:27:func Sizeof(v ArbitraryType) uintptr
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// unsafe/unsafe.go:32:func Offsetof(v ArbitraryType) uintptr
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// unsafe/unsafe.go:37:func Alignof(v ArbitraryType) uintptr
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588
src/pkg/exp/ssa/interp/interp.go
Normal file
588
src/pkg/exp/ssa/interp/interp.go
Normal file
@ -0,0 +1,588 @@
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// Package exp/ssa/interp defines an interpreter for the SSA
|
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// representation of Go programs.
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//
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// This interpreter is provided as an adjunct for testing the SSA
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// construction algorithm. Its purpose is to provide a minimal
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// metacircular implementation of the dynamic semantics of each SSA
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// instruction. It is not, and will never be, a production-quality Go
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// interpreter.
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//
|
||||
// The following is a partial list of Go features that are currently
|
||||
// unsupported or incomplete in the interpreter.
|
||||
//
|
||||
// * Unsafe operations, including all uses of unsafe.Pointer, are
|
||||
// impossible to support given the "boxed" value representation we
|
||||
// have chosen.
|
||||
//
|
||||
// * The reflect package is only partially implemented.
|
||||
//
|
||||
// * "sync/atomic" operations are not currently atomic due to the
|
||||
// "boxed" value representation: it is not possible to read, modify
|
||||
// and write an interface value atomically. As a consequence, Mutexes
|
||||
// are currently broken. TODO(adonovan): provide a metacircular
|
||||
// implementation of Mutex avoiding the broken atomic primitives.
|
||||
//
|
||||
// * recover is only partially implemented. Also, the interpreter
|
||||
// makes no attempt to distinguish target panics from interpreter
|
||||
// crashes.
|
||||
//
|
||||
// * map iteration is asymptotically inefficient.
|
||||
//
|
||||
// * the equivalence relation for structs doesn't skip over blank
|
||||
// fields.
|
||||
//
|
||||
// * the sizes of the int, uint and uintptr types in the target
|
||||
// program are assumed to be the same as those of the interpreter
|
||||
// itself.
|
||||
package interp
|
||||
|
||||
import (
|
||||
"exp/ssa"
|
||||
"fmt"
|
||||
"go/ast"
|
||||
"go/token"
|
||||
"go/types"
|
||||
"log"
|
||||
"os"
|
||||
"reflect"
|
||||
"runtime"
|
||||
)
|
||||
|
||||
type status int
|
||||
|
||||
const (
|
||||
stRunning status = iota
|
||||
stComplete
|
||||
stPanic
|
||||
)
|
||||
|
||||
type continuation int
|
||||
|
||||
const (
|
||||
kNext continuation = iota
|
||||
kReturn
|
||||
kJump
|
||||
)
|
||||
|
||||
// Mode is a bitmask of options affecting the interpreter.
|
||||
type Mode uint
|
||||
|
||||
const (
|
||||
DisableRecover Mode = 1 << iota // Disable recover() in target programs; show interpreter crash instead.
|
||||
EnableTracing // Print a trace of all instructions as they are interpreted.
|
||||
)
|
||||
|
||||
// State shared between all interpreted goroutines.
|
||||
type interpreter struct {
|
||||
prog *ssa.Program // the SSA program
|
||||
globals map[ssa.Value]*value // addresses of global variables (immutable)
|
||||
mode Mode // interpreter options
|
||||
reflectPackage *ssa.Package // the fake reflect package
|
||||
rtypeMethods ssa.MethodSet // the method set of rtype, which implements the reflect.Type interface.
|
||||
}
|
||||
|
||||
type frame struct {
|
||||
i *interpreter
|
||||
caller *frame
|
||||
fn *ssa.Function
|
||||
block, prevBlock *ssa.BasicBlock
|
||||
env map[ssa.Value]value // dynamic values of SSA variables
|
||||
locals []value
|
||||
defers []func()
|
||||
result value
|
||||
status status
|
||||
panic interface{}
|
||||
}
|
||||
|
||||
func (fr *frame) get(key ssa.Value) value {
|
||||
switch key := key.(type) {
|
||||
case nil:
|
||||
return nil
|
||||
case *ssa.Function, *ssa.Builtin:
|
||||
return key
|
||||
case *ssa.Literal:
|
||||
return literalValue(key)
|
||||
case *ssa.Global:
|
||||
if r, ok := fr.i.globals[key]; ok {
|
||||
return r
|
||||
}
|
||||
default:
|
||||
if r, ok := fr.env[key]; ok {
|
||||
return r
|
||||
}
|
||||
}
|
||||
panic(fmt.Sprintf("get: unexpected type %T", key))
|
||||
}
|
||||
|
||||
// findMethodSet returns the method set for type typ, which may be one
|
||||
// of the interpreter's fake types.
|
||||
func findMethodSet(i *interpreter, typ types.Type) ssa.MethodSet {
|
||||
if typ == rtypeType {
|
||||
return i.rtypeMethods
|
||||
}
|
||||
return i.prog.MethodSet(typ)
|
||||
}
|
||||
|
||||
// visitInstr interprets a single ssa.Instruction within the activation
|
||||
// record frame. It returns a continuation value indicating where to
|
||||
// read the next instruction from.
|
||||
func visitInstr(fr *frame, instr ssa.Instruction) continuation {
|
||||
switch instr := instr.(type) {
|
||||
case *ssa.UnOp:
|
||||
fr.env[instr] = unop(instr, fr.get(instr.X))
|
||||
|
||||
case *ssa.BinOp:
|
||||
fr.env[instr] = binop(instr.Op, fr.get(instr.X), fr.get(instr.Y))
|
||||
|
||||
case *ssa.Call:
|
||||
fn, args := prepareCall(fr, &instr.CallCommon)
|
||||
fr.env[instr] = call(fr.i, fr, instr.Pos, fn, args)
|
||||
|
||||
case *ssa.Conv:
|
||||
fr.env[instr] = conv(instr.Type(), instr.X.Type(), fr.get(instr.X))
|
||||
|
||||
case *ssa.ChangeInterface:
|
||||
x := fr.get(instr.X)
|
||||
if err := checkInterface(fr.i, instr.Type(), x.(iface)); err != "" {
|
||||
panic(err)
|
||||
}
|
||||
fr.env[instr] = x
|
||||
|
||||
case *ssa.MakeInterface:
|
||||
fr.env[instr] = iface{t: instr.X.Type(), v: fr.get(instr.X)}
|
||||
|
||||
case *ssa.Extract:
|
||||
fr.env[instr] = fr.get(instr.Tuple).(tuple)[instr.Index]
|
||||
|
||||
case *ssa.Slice:
|
||||
fr.env[instr] = slice(fr.get(instr.X), fr.get(instr.Low), fr.get(instr.High))
|
||||
|
||||
case *ssa.Ret:
|
||||
switch len(instr.Results) {
|
||||
case 0:
|
||||
case 1:
|
||||
fr.result = fr.get(instr.Results[0])
|
||||
default:
|
||||
var res []value
|
||||
for _, r := range instr.Results {
|
||||
res = append(res, copyVal(fr.get(r)))
|
||||
}
|
||||
fr.result = tuple(res)
|
||||
}
|
||||
return kReturn
|
||||
|
||||
case *ssa.Send:
|
||||
fr.get(instr.Chan).(chan value) <- copyVal(fr.get(instr.X))
|
||||
|
||||
case *ssa.Store:
|
||||
*fr.get(instr.Addr).(*value) = copyVal(fr.get(instr.Val))
|
||||
|
||||
case *ssa.If:
|
||||
succ := 1
|
||||
if fr.get(instr.Cond).(bool) {
|
||||
succ = 0
|
||||
}
|
||||
fr.prevBlock, fr.block = fr.block, fr.block.Succs[succ]
|
||||
return kJump
|
||||
|
||||
case *ssa.Jump:
|
||||
fr.prevBlock, fr.block = fr.block, fr.block.Succs[0]
|
||||
return kJump
|
||||
|
||||
case *ssa.Defer:
|
||||
fn, args := prepareCall(fr, &instr.CallCommon)
|
||||
fr.defers = append(fr.defers, func() { call(fr.i, fr, instr.Pos, fn, args) })
|
||||
|
||||
case *ssa.Go:
|
||||
fn, args := prepareCall(fr, &instr.CallCommon)
|
||||
go call(fr.i, nil, instr.Pos, fn, args)
|
||||
|
||||
case *ssa.MakeChan:
|
||||
fr.env[instr] = make(chan value, asInt(fr.get(instr.Size)))
|
||||
|
||||
case *ssa.Alloc:
|
||||
var addr *value
|
||||
if instr.Heap {
|
||||
// new
|
||||
addr = new(value)
|
||||
fr.env[instr] = addr
|
||||
} else {
|
||||
// local
|
||||
addr = fr.env[instr].(*value)
|
||||
}
|
||||
*addr = zero(indirectType(instr.Type()))
|
||||
|
||||
case *ssa.MakeSlice:
|
||||
slice := make([]value, asInt(fr.get(instr.Cap)))
|
||||
tElt := underlyingType(instr.Type()).(*types.Slice).Elt
|
||||
for i := range slice {
|
||||
slice[i] = zero(tElt)
|
||||
}
|
||||
fr.env[instr] = slice[:asInt(fr.get(instr.Len))]
|
||||
|
||||
case *ssa.MakeMap:
|
||||
reserve := 0
|
||||
if instr.Reserve != nil {
|
||||
reserve = asInt(fr.get(instr.Reserve))
|
||||
}
|
||||
fr.env[instr] = makeMap(underlyingType(instr.Type()).(*types.Map).Key, reserve)
|
||||
|
||||
case *ssa.Range:
|
||||
fr.env[instr] = rangeIter(fr.get(instr.X), instr.X.Type())
|
||||
|
||||
case *ssa.Next:
|
||||
fr.env[instr] = fr.get(instr.Iter).(iter).next()
|
||||
|
||||
case *ssa.FieldAddr:
|
||||
x := fr.get(instr.X)
|
||||
fr.env[instr] = &(*x.(*value)).(structure)[instr.Field]
|
||||
|
||||
case *ssa.Field:
|
||||
fr.env[instr] = copyVal(fr.get(instr.X).(structure)[instr.Field])
|
||||
|
||||
case *ssa.IndexAddr:
|
||||
x := fr.get(instr.X)
|
||||
idx := fr.get(instr.Index)
|
||||
switch x := x.(type) {
|
||||
case []value:
|
||||
fr.env[instr] = &x[asInt(idx)]
|
||||
case *value: // *array
|
||||
fr.env[instr] = &(*x).(array)[asInt(idx)]
|
||||
default:
|
||||
panic(fmt.Sprintf("unexpected x type in IndexAddr: %T", x))
|
||||
}
|
||||
|
||||
case *ssa.Index:
|
||||
fr.env[instr] = copyVal(fr.get(instr.X).(array)[asInt(fr.get(instr.Index))])
|
||||
|
||||
case *ssa.Lookup:
|
||||
fr.env[instr] = lookup(instr, fr.get(instr.X), fr.get(instr.Index))
|
||||
|
||||
case *ssa.MapUpdate:
|
||||
m := fr.get(instr.Map)
|
||||
key := fr.get(instr.Key)
|
||||
v := fr.get(instr.Value)
|
||||
switch m := m.(type) {
|
||||
case map[value]value:
|
||||
m[key] = v
|
||||
case *hashmap:
|
||||
m.insert(key.(hashable), v)
|
||||
default:
|
||||
panic(fmt.Sprintf("illegal map type: %T", m))
|
||||
}
|
||||
|
||||
case *ssa.TypeAssert:
|
||||
fr.env[instr] = typeAssert(fr.i, instr, fr.get(instr.X).(iface))
|
||||
|
||||
case *ssa.MakeClosure:
|
||||
var bindings []value
|
||||
for _, binding := range instr.Bindings {
|
||||
bindings = append(bindings, fr.get(binding))
|
||||
}
|
||||
fr.env[instr] = &closure{instr.Fn, bindings}
|
||||
|
||||
case *ssa.Phi:
|
||||
for i, pred := range instr.Block_.Preds {
|
||||
if fr.prevBlock == pred {
|
||||
fr.env[instr] = fr.get(instr.Edges[i])
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
case *ssa.Select:
|
||||
var cases []reflect.SelectCase
|
||||
if !instr.Blocking {
|
||||
cases = append(cases, reflect.SelectCase{
|
||||
Dir: reflect.SelectDefault,
|
||||
})
|
||||
}
|
||||
for _, state := range instr.States {
|
||||
var dir reflect.SelectDir
|
||||
if state.Dir == ast.RECV {
|
||||
dir = reflect.SelectRecv
|
||||
} else {
|
||||
dir = reflect.SelectSend
|
||||
}
|
||||
var send reflect.Value
|
||||
if state.Send != nil {
|
||||
send = reflect.ValueOf(fr.get(state.Send))
|
||||
}
|
||||
cases = append(cases, reflect.SelectCase{
|
||||
Dir: dir,
|
||||
Chan: reflect.ValueOf(fr.get(state.Chan)),
|
||||
Send: send,
|
||||
})
|
||||
}
|
||||
chosen, recv, recvOk := reflect.Select(cases)
|
||||
if !instr.Blocking {
|
||||
chosen-- // default case should have index -1.
|
||||
}
|
||||
var recvV value
|
||||
if recvOk {
|
||||
// No need to copy since send makes an unaliased copy.
|
||||
recvV = recv.Interface().(value)
|
||||
} else if chosen != -1 {
|
||||
// Ensure we provide a type-appropriate zero value.
|
||||
recvV = zero(underlyingType(instr.States[chosen].Chan.Type()).(*types.Chan).Elt)
|
||||
}
|
||||
fr.env[instr] = tuple{chosen, recvV, recvOk}
|
||||
|
||||
default:
|
||||
panic(fmt.Sprintf("unexpected instruction: %T", instr))
|
||||
}
|
||||
|
||||
// if val, ok := instr.(ssa.Value); ok {
|
||||
// fmt.Println(toString(fr.env[val])) // debugging
|
||||
// }
|
||||
|
||||
return kNext
|
||||
}
|
||||
|
||||
// prepareCall determines the function value and argument values for a
|
||||
// function call in a Call, Go or Defer instruction, peforming
|
||||
// interface method lookup if needed.
|
||||
//
|
||||
func prepareCall(fr *frame, call *ssa.CallCommon) (fn value, args []value) {
|
||||
if call.Func != nil {
|
||||
// Function call.
|
||||
fn = fr.get(call.Func)
|
||||
} else {
|
||||
// Interface method invocation.
|
||||
recv := fr.get(call.Recv).(iface)
|
||||
if recv.t == nil {
|
||||
panic("method invoked on nil interface")
|
||||
}
|
||||
meth := underlyingType(call.Recv.Type()).(*types.Interface).Methods[call.Method]
|
||||
id := ssa.IdFromQualifiedName(meth.QualifiedName)
|
||||
m := findMethodSet(fr.i, recv.t)[id]
|
||||
if m == nil {
|
||||
// Unreachable in well-typed programs.
|
||||
panic(fmt.Sprintf("method set for dynamic type %v does not contain %s", recv.t, id))
|
||||
}
|
||||
_, aptr := recv.v.(*value) // actual pointerness
|
||||
_, fptr := m.Signature.Recv.Type.(*types.Pointer) // formal pointerness
|
||||
switch {
|
||||
case aptr == fptr:
|
||||
args = append(args, copyVal(recv.v))
|
||||
case aptr:
|
||||
// Calling func(T) with a *T receiver: make a copy.
|
||||
args = append(args, copyVal(*recv.v.(*value)))
|
||||
case fptr:
|
||||
panic("illegal call of *T method with T receiver")
|
||||
}
|
||||
fn = m
|
||||
}
|
||||
for _, arg := range call.Args {
|
||||
args = append(args, fr.get(arg))
|
||||
}
|
||||
return
|
||||
}
|
||||
|
||||
// call interprets a call to a function (function, builtin or closure)
|
||||
// fn with arguments args, returning its result.
|
||||
// callpos is the position of the callsite.
|
||||
//
|
||||
func call(i *interpreter, caller *frame, callpos token.Pos, fn value, args []value) value {
|
||||
switch fn := fn.(type) {
|
||||
case *ssa.Function:
|
||||
if fn == nil {
|
||||
panic("call of nil function") // nil of func type
|
||||
}
|
||||
return callSSA(i, caller, callpos, fn, args, nil)
|
||||
case *closure:
|
||||
return callSSA(i, caller, callpos, fn.Fn, args, fn.Env)
|
||||
case *ssa.Builtin:
|
||||
return callBuiltin(caller, callpos, fn, args)
|
||||
}
|
||||
panic(fmt.Sprintf("cannot call %T", fn))
|
||||
}
|
||||
|
||||
func loc(fset *token.FileSet, pos token.Pos) string {
|
||||
if pos == token.NoPos {
|
||||
return ""
|
||||
}
|
||||
return " at " + fset.Position(pos).String()
|
||||
}
|
||||
|
||||
// callSSA interprets a call to function fn with arguments args,
|
||||
// and lexical environment env, returning its result.
|
||||
// callpos is the position of the callsite.
|
||||
//
|
||||
func callSSA(i *interpreter, caller *frame, callpos token.Pos, fn *ssa.Function, args []value, env []value) value {
|
||||
if i.mode&EnableTracing != 0 {
|
||||
fset := fn.Prog.Files
|
||||
// TODO(adonovan): fix: loc() lies for external functions.
|
||||
fmt.Fprintf(os.Stderr, "Entering %s%s.\n", fn.FullName(), loc(fset, fn.Pos))
|
||||
suffix := ""
|
||||
if caller != nil {
|
||||
suffix = ", resuming " + caller.fn.FullName() + loc(fset, callpos)
|
||||
}
|
||||
defer fmt.Fprintf(os.Stderr, "Leaving %s%s.\n", fn.FullName(), suffix)
|
||||
}
|
||||
if fn.Enclosing == nil {
|
||||
name := fn.FullName()
|
||||
if ext := externals[name]; ext != nil {
|
||||
if i.mode&EnableTracing != 0 {
|
||||
fmt.Fprintln(os.Stderr, "\t(external)")
|
||||
}
|
||||
return ext(fn, args, env)
|
||||
}
|
||||
if fn.Blocks == nil {
|
||||
panic("no code for function: " + name)
|
||||
}
|
||||
}
|
||||
fr := &frame{
|
||||
i: i,
|
||||
caller: caller, // currently unused; for unwinding.
|
||||
fn: fn,
|
||||
env: make(map[ssa.Value]value),
|
||||
block: fn.Blocks[0],
|
||||
locals: make([]value, len(fn.Locals)),
|
||||
}
|
||||
for i, l := range fn.Locals {
|
||||
fr.locals[i] = zero(indirectType(l.Type()))
|
||||
fr.env[l] = &fr.locals[i]
|
||||
}
|
||||
for i, p := range fn.Params {
|
||||
fr.env[p] = args[i]
|
||||
}
|
||||
for i, fv := range fn.FreeVars {
|
||||
fr.env[fv] = env[i]
|
||||
}
|
||||
var instr ssa.Instruction
|
||||
|
||||
defer func() {
|
||||
if fr.status != stComplete {
|
||||
if fr.i.mode&DisableRecover != 0 {
|
||||
return // let interpreter crash
|
||||
}
|
||||
fr.status, fr.panic = stPanic, recover()
|
||||
}
|
||||
for i := range fr.defers {
|
||||
if fr.i.mode&EnableTracing != 0 {
|
||||
fmt.Fprintln(os.Stderr, "Invoking deferred function", i)
|
||||
}
|
||||
fr.defers[len(fr.defers)-1-i]()
|
||||
}
|
||||
// Destroy the locals to avoid accidental use after return.
|
||||
for i := range fn.Locals {
|
||||
fr.locals[i] = bad{}
|
||||
}
|
||||
if fr.status == stPanic {
|
||||
panic(fr.panic) // panic stack is not entirely clean
|
||||
}
|
||||
}()
|
||||
|
||||
for {
|
||||
if i.mode&EnableTracing != 0 {
|
||||
fmt.Fprintf(os.Stderr, ".%s:\n", fr.block.Name)
|
||||
}
|
||||
block:
|
||||
for _, instr = range fr.block.Instrs {
|
||||
if i.mode&EnableTracing != 0 {
|
||||
if v, ok := instr.(ssa.Value); ok {
|
||||
fmt.Fprintln(os.Stderr, "\t", v.Name(), "=", instr)
|
||||
} else {
|
||||
fmt.Fprintln(os.Stderr, "\t", instr)
|
||||
}
|
||||
}
|
||||
switch visitInstr(fr, instr) {
|
||||
case kReturn:
|
||||
fr.status = stComplete
|
||||
return fr.result
|
||||
case kNext:
|
||||
// no-op
|
||||
case kJump:
|
||||
break block
|
||||
}
|
||||
}
|
||||
}
|
||||
panic("unreachable")
|
||||
}
|
||||
|
||||
// setGlobal sets the value of a system-initialized global variable.
|
||||
func setGlobal(i *interpreter, pkg *ssa.Package, name string, v value) {
|
||||
if g, ok := i.globals[pkg.Var(name)]; ok {
|
||||
*g = v
|
||||
return
|
||||
}
|
||||
panic("no global variable: " + pkg.Name() + "." + name)
|
||||
}
|
||||
|
||||
// Interpret interprets the Go program whose main package is mainpkg.
|
||||
// mode specifies various interpreter options. filename and args are
|
||||
// the initial values of os.Args for the target program.
|
||||
//
|
||||
func Interpret(mainpkg *ssa.Package, mode Mode, filename string, args []string) {
|
||||
i := &interpreter{
|
||||
prog: mainpkg.Prog,
|
||||
globals: make(map[ssa.Value]*value),
|
||||
mode: mode,
|
||||
}
|
||||
initReflect(i)
|
||||
|
||||
for importPath, pkg := range i.prog.Packages {
|
||||
// Initialize global storage.
|
||||
for _, m := range pkg.Members {
|
||||
switch v := m.(type) {
|
||||
case *ssa.Global:
|
||||
cell := zero(indirectType(v.Type()))
|
||||
i.globals[v] = &cell
|
||||
}
|
||||
}
|
||||
|
||||
// Ad-hoc initialization for magic system variables.
|
||||
switch importPath {
|
||||
case "syscall":
|
||||
var envs []value
|
||||
for _, s := range os.Environ() {
|
||||
envs = append(envs, s)
|
||||
}
|
||||
setGlobal(i, pkg, "envs", envs)
|
||||
|
||||
case "runtime":
|
||||
// TODO(gri): expose go/types.sizeof so we can
|
||||
// avoid this fragile magic number;
|
||||
// unsafe.Sizeof(memStats) won't work since gc
|
||||
// and go/types have different sizeof
|
||||
// functions.
|
||||
setGlobal(i, pkg, "sizeof_C_MStats", uintptr(3450))
|
||||
|
||||
case "os":
|
||||
Args := []value{filename}
|
||||
for _, s := range args {
|
||||
Args = append(Args, s)
|
||||
}
|
||||
setGlobal(i, pkg, "Args", Args)
|
||||
}
|
||||
}
|
||||
|
||||
// Top-level error handler.
|
||||
complete := false
|
||||
defer func() {
|
||||
if complete || i.mode&DisableRecover != 0 {
|
||||
return
|
||||
}
|
||||
// TODO(adonovan): stop the world and dump goroutines.
|
||||
switch p := recover().(type) {
|
||||
case targetPanic:
|
||||
fmt.Fprintln(os.Stderr, "panic:", toString(p.v))
|
||||
case runtime.Error:
|
||||
fmt.Fprintln(os.Stderr, "panic:", p.Error())
|
||||
case string:
|
||||
fmt.Fprintln(os.Stderr, "panic:", p)
|
||||
default:
|
||||
panic(fmt.Sprintf("unexpected panic type: %T", p))
|
||||
}
|
||||
os.Exit(1)
|
||||
}()
|
||||
|
||||
// Run!
|
||||
call(i, nil, token.NoPos, mainpkg.Init, nil)
|
||||
if mainFn := mainpkg.Func("main"); mainFn != nil {
|
||||
call(i, nil, token.NoPos, mainFn, nil)
|
||||
} else {
|
||||
log.Fatalf("no main function")
|
||||
}
|
||||
complete = true
|
||||
}
|
||||
101
src/pkg/exp/ssa/interp/map.go
Normal file
101
src/pkg/exp/ssa/interp/map.go
Normal file
@ -0,0 +1,101 @@
|
||||
package interp
|
||||
|
||||
// Custom hashtable atop map.
|
||||
// For use when the key's equivalence relation is not consistent with ==.
|
||||
|
||||
// The Go specification doesn't address the atomicity of map operations.
|
||||
// The FAQ states that an implementation is permitted to crash on
|
||||
// concurrent map access.
|
||||
|
||||
import (
|
||||
"go/types"
|
||||
)
|
||||
|
||||
type hashable interface {
|
||||
hash() int
|
||||
eq(x interface{}) bool
|
||||
}
|
||||
|
||||
type entry struct {
|
||||
key hashable
|
||||
value value
|
||||
next *entry
|
||||
}
|
||||
|
||||
// A hashtable atop the built-in map. Since each bucket contains
|
||||
// exactly one hash value, there's no need to perform hash-equality
|
||||
// tests when walking the linked list. Rehashing is done by the
|
||||
// underlying map.
|
||||
type hashmap struct {
|
||||
table map[int]*entry
|
||||
length int // number of entries in map
|
||||
}
|
||||
|
||||
// makeMap returns an empty initialized map of key type kt,
|
||||
// preallocating space for reserve elements.
|
||||
func makeMap(kt types.Type, reserve int) value {
|
||||
if usesBuiltinMap(kt) {
|
||||
return make(map[value]value, reserve)
|
||||
}
|
||||
return &hashmap{table: make(map[int]*entry, reserve)}
|
||||
}
|
||||
|
||||
// delete removes the association for key k, if any.
|
||||
func (m *hashmap) delete(k hashable) {
|
||||
hash := k.hash()
|
||||
head := m.table[hash]
|
||||
if head != nil {
|
||||
if k.eq(head.key) {
|
||||
m.table[hash] = head.next
|
||||
m.length--
|
||||
return
|
||||
}
|
||||
prev := head
|
||||
for e := head.next; e != nil; e = e.next {
|
||||
if k.eq(e.key) {
|
||||
prev.next = e.next
|
||||
m.length--
|
||||
return
|
||||
}
|
||||
prev = e
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// lookup returns the value associated with key k, if present, or
|
||||
// value(nil) otherwise.
|
||||
func (m *hashmap) lookup(k hashable) value {
|
||||
hash := k.hash()
|
||||
for e := m.table[hash]; e != nil; e = e.next {
|
||||
if k.eq(e.key) {
|
||||
return e.value
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
// insert updates the map to associate key k with value v. If there
|
||||
// was already an association for an eq() (though not necessarily ==)
|
||||
// k, the previous key remains in the map and its associated value is
|
||||
// updated.
|
||||
func (m *hashmap) insert(k hashable, v value) {
|
||||
hash := k.hash()
|
||||
head := m.table[hash]
|
||||
for e := head; e != nil; e = e.next {
|
||||
if k.eq(e.key) {
|
||||
e.value = v
|
||||
return
|
||||
}
|
||||
}
|
||||
m.table[hash] = &entry{
|
||||
key: k,
|
||||
value: v,
|
||||
next: head,
|
||||
}
|
||||
m.length++
|
||||
}
|
||||
|
||||
// len returns the number of key/value associations in the map.
|
||||
func (m *hashmap) len() int {
|
||||
return m.length
|
||||
}
|
||||
1373
src/pkg/exp/ssa/interp/ops.go
Normal file
1373
src/pkg/exp/ssa/interp/ops.go
Normal file
File diff suppressed because it is too large
Load Diff
413
src/pkg/exp/ssa/interp/reflect.go
Normal file
413
src/pkg/exp/ssa/interp/reflect.go
Normal file
@ -0,0 +1,413 @@
|
||||
package interp
|
||||
|
||||
// Emulated "reflect" package.
|
||||
//
|
||||
// We completely replace the built-in "reflect" package.
|
||||
// The only thing clients can depend upon are that reflect.Type is an
|
||||
// interface and reflect.Value is an (opaque) struct.
|
||||
|
||||
import (
|
||||
"exp/ssa"
|
||||
"fmt"
|
||||
"go/types"
|
||||
"reflect"
|
||||
"unsafe"
|
||||
)
|
||||
|
||||
// rtype is the concrete type the interpreter uses to implement the
|
||||
// reflect.Type interface. Since its type is opaque to the target
|
||||
// language, we use a types.Basic.
|
||||
//
|
||||
// type rtype <opaque>
|
||||
var rtypeType = makeNamedType("rtype", &types.Basic{Name: "rtype"})
|
||||
|
||||
// Value is the interpreter's version of reflect.Value.
|
||||
//
|
||||
// Since it has no public fields and we control all the functions in
|
||||
// the reflect package, it doesn't matter that it is not the same as
|
||||
// the real Value struct.
|
||||
//
|
||||
// A reflect.Value contains the same two fields as the interpreter's
|
||||
// iface struct.
|
||||
//
|
||||
// type Value struct {
|
||||
// t rtype
|
||||
// v Value
|
||||
// }
|
||||
//
|
||||
// Even though it's a struct, we use a types.Basic since no-one cares.
|
||||
var reflectValueType = makeNamedType("Value", &types.Basic{Name: "Value"})
|
||||
|
||||
func makeNamedType(name string, underlying types.Type) *types.NamedType {
|
||||
nt := &types.NamedType{Underlying: underlying}
|
||||
nt.Obj = &types.TypeName{Name: name, Type: nt}
|
||||
return nt
|
||||
}
|
||||
|
||||
func makeReflectValue(t types.Type, v value) value {
|
||||
return structure{rtype{t}, v}
|
||||
}
|
||||
|
||||
// Given a reflect.Value, returns its rtype.
|
||||
func rV2T(v value) rtype {
|
||||
return v.(structure)[0].(rtype)
|
||||
}
|
||||
|
||||
// Given a reflect.Value, returns the underlying interpreter value.
|
||||
func rV2V(v value) value {
|
||||
return v.(structure)[1]
|
||||
}
|
||||
|
||||
// makeReflectType boxes up an rtype in a reflect.Type interface.
|
||||
func makeReflectType(rt rtype) value {
|
||||
return iface{rtypeType, rt}
|
||||
}
|
||||
|
||||
func ext۰reflect۰Init(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func()
|
||||
return nil
|
||||
}
|
||||
|
||||
func ext۰reflect۰rtype۰Bits(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (t reflect.rtype) int
|
||||
rt := args[0].(rtype).t
|
||||
basic, ok := underlyingType(rt).(*types.Basic)
|
||||
if !ok {
|
||||
panic(fmt.Sprintf("reflect.Type.Bits(%T): non-basic type", rt))
|
||||
}
|
||||
switch basic.Kind {
|
||||
case types.Int8, types.Uint8:
|
||||
return 8
|
||||
case types.Int16, types.Uint16:
|
||||
return 16
|
||||
case types.Int, types.UntypedInt:
|
||||
// Assume sizeof(int) is same on host and target; ditto uint.
|
||||
return reflect.TypeOf(int(0)).Bits()
|
||||
case types.Uintptr:
|
||||
// Assume sizeof(uintptr) is same on host and target.
|
||||
return reflect.TypeOf(uintptr(0)).Bits()
|
||||
case types.Int32, types.Uint32:
|
||||
return 32
|
||||
case types.Int64, types.Uint64:
|
||||
return 64
|
||||
case types.Float32:
|
||||
return 32
|
||||
case types.Float64, types.UntypedFloat:
|
||||
return 64
|
||||
case types.Complex64:
|
||||
return 64
|
||||
case types.Complex128, types.UntypedComplex:
|
||||
return 128
|
||||
default:
|
||||
panic(fmt.Sprintf("reflect.Type.Bits(%s)", basic))
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func ext۰reflect۰rtype۰Elem(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (t reflect.rtype) reflect.Type
|
||||
var elem types.Type
|
||||
switch rt := underlyingType(args[0].(rtype).t).(type) {
|
||||
case *types.Array:
|
||||
elem = rt.Elt
|
||||
case *types.Chan:
|
||||
elem = rt.Elt
|
||||
case *types.Map:
|
||||
elem = rt.Elt
|
||||
case *types.Pointer:
|
||||
elem = rt.Base
|
||||
case *types.Slice:
|
||||
elem = rt.Elt
|
||||
default:
|
||||
panic(fmt.Sprintf("reflect.Type.Elem(%T)", rt))
|
||||
}
|
||||
return makeReflectType(rtype{elem})
|
||||
}
|
||||
|
||||
func ext۰reflect۰rtype۰Kind(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (t reflect.rtype) uint
|
||||
return uint(reflectKind(args[0].(rtype).t))
|
||||
}
|
||||
|
||||
func ext۰reflect۰rtype۰String(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (t reflect.rtype) string
|
||||
return args[0].(rtype).t.String()
|
||||
}
|
||||
|
||||
func ext۰reflect۰TypeOf(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (t reflect.rtype) string
|
||||
return makeReflectType(rtype{args[0].(iface).t})
|
||||
}
|
||||
|
||||
func ext۰reflect۰ValueOf(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (interface{}) reflect.Value
|
||||
itf := args[0].(iface)
|
||||
return makeReflectValue(itf.t, itf.v)
|
||||
}
|
||||
|
||||
func reflectKind(t types.Type) reflect.Kind {
|
||||
switch t := t.(type) {
|
||||
case *types.NamedType:
|
||||
return reflectKind(t.Underlying)
|
||||
case *types.Basic:
|
||||
switch t.Kind {
|
||||
case types.Bool:
|
||||
return reflect.Bool
|
||||
case types.Int:
|
||||
return reflect.Int
|
||||
case types.Int8:
|
||||
return reflect.Int8
|
||||
case types.Int16:
|
||||
return reflect.Int16
|
||||
case types.Int32:
|
||||
return reflect.Int32
|
||||
case types.Int64:
|
||||
return reflect.Int64
|
||||
case types.Uint:
|
||||
return reflect.Uint
|
||||
case types.Uint8:
|
||||
return reflect.Uint8
|
||||
case types.Uint16:
|
||||
return reflect.Uint16
|
||||
case types.Uint32:
|
||||
return reflect.Uint32
|
||||
case types.Uint64:
|
||||
return reflect.Uint64
|
||||
case types.Uintptr:
|
||||
return reflect.Uintptr
|
||||
case types.Float32:
|
||||
return reflect.Float32
|
||||
case types.Float64:
|
||||
return reflect.Float64
|
||||
case types.Complex64:
|
||||
return reflect.Complex64
|
||||
case types.Complex128:
|
||||
return reflect.Complex128
|
||||
case types.String:
|
||||
return reflect.String
|
||||
case types.UnsafePointer:
|
||||
return reflect.UnsafePointer
|
||||
}
|
||||
case *types.Array:
|
||||
return reflect.Array
|
||||
case *types.Chan:
|
||||
return reflect.Chan
|
||||
case *types.Signature:
|
||||
return reflect.Func
|
||||
case *types.Interface:
|
||||
return reflect.Interface
|
||||
case *types.Map:
|
||||
return reflect.Map
|
||||
case *types.Pointer:
|
||||
return reflect.Ptr
|
||||
case *types.Slice:
|
||||
return reflect.Slice
|
||||
case *types.Struct:
|
||||
return reflect.Struct
|
||||
}
|
||||
panic(fmt.Sprint("unexpected type: ", t))
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰Kind(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (reflect.Value) uint
|
||||
return uint(reflectKind(rV2T(args[0]).t))
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰Type(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (reflect.Value) reflect.Type
|
||||
return makeReflectType(rV2T(args[0]))
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰Len(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (reflect.Value) int
|
||||
switch v := rV2V(args[0]).(type) {
|
||||
case string:
|
||||
return len(v)
|
||||
case array:
|
||||
return len(v)
|
||||
case chan value:
|
||||
return cap(v)
|
||||
case []value:
|
||||
return len(v)
|
||||
case *hashmap:
|
||||
return v.len()
|
||||
case map[value]value:
|
||||
return len(v)
|
||||
default:
|
||||
panic(fmt.Sprintf("reflect.(Value).Len(%V)", v))
|
||||
}
|
||||
return nil // unreachable
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰NumField(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (reflect.Value) int
|
||||
return len(rV2V(args[0]).(structure))
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰Pointer(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (v reflect.Value) uintptr
|
||||
switch v := rV2V(args[0]).(type) {
|
||||
case *value:
|
||||
return uintptr(unsafe.Pointer(v))
|
||||
case chan value:
|
||||
return reflect.ValueOf(v).Pointer()
|
||||
case []value:
|
||||
return reflect.ValueOf(v).Pointer()
|
||||
case *hashmap:
|
||||
return reflect.ValueOf(v.table).Pointer()
|
||||
case map[value]value:
|
||||
return reflect.ValueOf(v).Pointer()
|
||||
case *ssa.Function:
|
||||
return uintptr(unsafe.Pointer(v))
|
||||
default:
|
||||
panic(fmt.Sprintf("reflect.(Value).Pointer(%T)", v))
|
||||
}
|
||||
return nil // unreachable
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰Index(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (v reflect.Value, i int) Value
|
||||
i := args[1].(int)
|
||||
t := underlyingType(rV2T(args[0]).t)
|
||||
switch v := rV2V(args[0]).(type) {
|
||||
case array:
|
||||
return makeReflectValue(t.(*types.Array).Elt, v[i])
|
||||
case []value:
|
||||
return makeReflectValue(t.(*types.Slice).Elt, v[i])
|
||||
default:
|
||||
panic(fmt.Sprintf("reflect.(Value).Index(%T)", v))
|
||||
}
|
||||
return nil // unreachable
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰CanAddr(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (v reflect.Value) bool
|
||||
// Always false for our representation.
|
||||
return false
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰CanInterface(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (v reflect.Value) bool
|
||||
// Always true for our representation.
|
||||
return true
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰Elem(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (v reflect.Value) reflect.Value
|
||||
switch x := rV2V(args[0]).(type) {
|
||||
case iface:
|
||||
return makeReflectValue(x.t, x.v)
|
||||
case *value:
|
||||
return makeReflectValue(underlyingType(rV2T(args[0]).t).(*types.Pointer).Base, *x)
|
||||
default:
|
||||
panic(fmt.Sprintf("reflect.(Value).Elem(%T)", x))
|
||||
}
|
||||
return nil // unreachable
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰Field(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (v reflect.Value, i int) reflect.Value
|
||||
v := args[0]
|
||||
i := args[1].(int)
|
||||
return makeReflectValue(underlyingType(rV2T(v).t).(*types.Struct).Fields[i].Type, rV2V(v).(structure)[i])
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰Interface(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (v reflect.Value) interface{}
|
||||
return ext۰reflect۰valueInterface(fn, args, slots)
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰Int(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (reflect.Value) int64
|
||||
switch x := rV2V(args[0]).(type) {
|
||||
case int:
|
||||
return int64(x)
|
||||
case int8:
|
||||
return int64(x)
|
||||
case int16:
|
||||
return int64(x)
|
||||
case int32:
|
||||
return int64(x)
|
||||
case int64:
|
||||
return x
|
||||
default:
|
||||
panic(fmt.Sprintf("reflect.(Value).Int(%T)", x))
|
||||
}
|
||||
return nil // unreachable
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰IsNil(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (reflect.Value) bool
|
||||
switch x := rV2V(args[0]).(type) {
|
||||
case *value:
|
||||
return x == nil
|
||||
case chan value:
|
||||
return x == nil
|
||||
case map[value]value:
|
||||
return x == nil
|
||||
case *hashmap:
|
||||
return x == nil
|
||||
case iface:
|
||||
return x.t == nil
|
||||
case []value:
|
||||
return x == nil
|
||||
case *ssa.Function:
|
||||
return x == nil
|
||||
case *ssa.Builtin:
|
||||
return x == nil
|
||||
case *closure:
|
||||
return x == nil
|
||||
default:
|
||||
panic(fmt.Sprintf("reflect.(Value).IsNil(%T)", x))
|
||||
}
|
||||
return nil // unreachable
|
||||
}
|
||||
|
||||
func ext۰reflect۰Value۰IsValid(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (reflect.Value) bool
|
||||
return rV2V(args[0]) != nil
|
||||
}
|
||||
|
||||
func ext۰reflect۰valueInterface(fn *ssa.Function, args []value, slots []value) value {
|
||||
// Signature: func (v reflect.Value, safe bool) interface{}
|
||||
v := args[0].(structure)
|
||||
return iface{rV2T(v).t, rV2V(v)}
|
||||
}
|
||||
|
||||
// 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 {
|
||||
fn := &ssa.Function{
|
||||
Name_: name,
|
||||
Pkg: pkg,
|
||||
Prog: pkg.Prog,
|
||||
}
|
||||
// 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.
|
||||
fn.Signature = &types.Signature{Recv: &types.Var{
|
||||
Name: "recv",
|
||||
Type: recvType,
|
||||
}}
|
||||
return fn
|
||||
}
|
||||
|
||||
func initReflect(i *interpreter) {
|
||||
i.reflectPackage = &ssa.Package{
|
||||
Prog: i.prog,
|
||||
Types: &types.Package{
|
||||
Name: "reflect",
|
||||
Path: "reflect",
|
||||
Complete: true,
|
||||
},
|
||||
ImportPath: "reflect",
|
||||
Members: make(map[string]ssa.Member),
|
||||
}
|
||||
|
||||
i.rtypeMethods = ssa.MethodSet{
|
||||
ssa.Id{nil, "Bits"}: newMethod(i.reflectPackage, rtypeType, "Bits"),
|
||||
ssa.Id{nil, "Elem"}: newMethod(i.reflectPackage, rtypeType, "Elem"),
|
||||
ssa.Id{nil, "Kind"}: newMethod(i.reflectPackage, rtypeType, "Kind"),
|
||||
ssa.Id{nil, "String"}: newMethod(i.reflectPackage, rtypeType, "String"),
|
||||
}
|
||||
}
|
||||
492
src/pkg/exp/ssa/interp/value.go
Normal file
492
src/pkg/exp/ssa/interp/value.go
Normal file
@ -0,0 +1,492 @@
|
||||
package interp
|
||||
|
||||
// Values
|
||||
//
|
||||
// All interpreter values are "boxed" in the empty interface, value.
|
||||
// The range of possible dynamic types within value are:
|
||||
//
|
||||
// - bool
|
||||
// - numbers (all built-in int/float/complex types are distinguished)
|
||||
// - string
|
||||
// - map[value]value --- maps for which usesBuiltinMap(keyType)
|
||||
// *hashmap --- maps for which !usesBuiltinMap(keyType)
|
||||
// - chan value
|
||||
// - []value --- slices
|
||||
// - iface --- interfaces.
|
||||
// - structure --- structs. Fields are ordered and accessed by numeric indices.
|
||||
// - array --- arrays.
|
||||
// - *value --- pointers. Careful: *value is a distinct type from *array etc.
|
||||
// - *ssa.Function \
|
||||
// *ssa.Builtin } --- functions.
|
||||
// *closure /
|
||||
// - tuple --- as returned by Ret, Next, "value,ok" modes, etc.
|
||||
// - iter --- iterators from 'range'.
|
||||
// - bad --- a poison pill for locals that have gone out of scope.
|
||||
// - rtype -- the interpreter's concrete implementation of reflect.Type
|
||||
//
|
||||
// Note that nil is not on this list.
|
||||
//
|
||||
// Pay close attention to whether or not the dynamic type is a pointer.
|
||||
// The compiler cannot help you since value is an empty interface.
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"exp/ssa"
|
||||
"fmt"
|
||||
"go/types"
|
||||
"io"
|
||||
"reflect"
|
||||
"strings"
|
||||
"unsafe"
|
||||
)
|
||||
|
||||
type value interface{}
|
||||
|
||||
type tuple []value
|
||||
|
||||
type array []value
|
||||
|
||||
type iface struct {
|
||||
t types.Type // never an "untyped" type
|
||||
v value
|
||||
}
|
||||
|
||||
type structure []value
|
||||
|
||||
// For map, array, *array, slice, string or channel.
|
||||
type iter interface {
|
||||
// next returns a Tuple (key, value, ok).
|
||||
// key and value are unaliased, e.g. copies of the sequence element.
|
||||
next() tuple
|
||||
}
|
||||
|
||||
type closure struct {
|
||||
Fn *ssa.Function
|
||||
Env []value
|
||||
}
|
||||
|
||||
type bad struct{}
|
||||
|
||||
type rtype struct {
|
||||
t types.Type
|
||||
}
|
||||
|
||||
// Hash functions and equivalence relation:
|
||||
|
||||
// hashString computes the FNV hash of s.
|
||||
func hashString(s string) int {
|
||||
var h uint32
|
||||
for i := 0; i < len(s); i++ {
|
||||
h ^= uint32(s[i])
|
||||
h *= 16777619
|
||||
}
|
||||
return int(h)
|
||||
}
|
||||
|
||||
// hashType returns a hash for t such that
|
||||
// types.IsIdentical(x, y) => hashType(x) == hashType(y).
|
||||
func hashType(t types.Type) int {
|
||||
return hashString(t.String()) // TODO(gri): provide a better hash
|
||||
}
|
||||
|
||||
// usesBuiltinMap returns true if the built-in hash function and
|
||||
// equivalence relation for type t are consistent with those of the
|
||||
// interpreter's representation of type t. Such types are: all basic
|
||||
// types (bool, numbers, string), pointers and channels.
|
||||
//
|
||||
// usesBuiltinMap returns false for types that require a custom map
|
||||
// implementation: interfaces, arrays and structs.
|
||||
//
|
||||
// Panic ensues if t is an invalid map key type: function, map or slice.
|
||||
func usesBuiltinMap(t types.Type) bool {
|
||||
switch t := t.(type) {
|
||||
case *types.Basic, *types.Chan, *types.Pointer:
|
||||
return true
|
||||
case *types.NamedType:
|
||||
return usesBuiltinMap(t.Underlying)
|
||||
case *types.Interface, *types.Array, *types.Struct:
|
||||
return false
|
||||
}
|
||||
panic(fmt.Sprintf("invalid map key type: %T", t))
|
||||
}
|
||||
|
||||
func (x array) eq(_y interface{}) bool {
|
||||
y := _y.(array)
|
||||
for i, xi := range x {
|
||||
if !equals(xi, y[i]) {
|
||||
return false
|
||||
}
|
||||
}
|
||||
return true
|
||||
}
|
||||
|
||||
func (x array) hash() int {
|
||||
h := 0
|
||||
for _, xi := range x {
|
||||
h += hash(xi)
|
||||
}
|
||||
return h
|
||||
}
|
||||
|
||||
func (x structure) eq(_y interface{}) bool {
|
||||
y := _y.(structure)
|
||||
// TODO(adonovan): fix: only non-blank fields should be
|
||||
// compared. This requires that we have type information
|
||||
// available from the enclosing == operation or map access;
|
||||
// the value is not sufficient.
|
||||
for i, xi := range x {
|
||||
if !equals(xi, y[i]) {
|
||||
return false
|
||||
}
|
||||
}
|
||||
return true
|
||||
}
|
||||
|
||||
func (x structure) hash() int {
|
||||
h := 0
|
||||
for _, xi := range x {
|
||||
h += hash(xi)
|
||||
}
|
||||
return h
|
||||
}
|
||||
|
||||
func (x iface) eq(_y interface{}) bool {
|
||||
y := _y.(iface)
|
||||
return types.IsIdentical(x.t, y.t) && (x.t == nil || equals(x.v, y.v))
|
||||
}
|
||||
|
||||
func (x iface) hash() int {
|
||||
return hashType(x.t)*8581 + hash(x.v)
|
||||
}
|
||||
|
||||
func (x rtype) hash() int {
|
||||
return hashType(x.t)
|
||||
}
|
||||
|
||||
func (x rtype) eq(y interface{}) bool {
|
||||
return types.IsIdentical(x.t, y.(rtype).t)
|
||||
}
|
||||
|
||||
// equals returns true iff x and y are equal according to Go's
|
||||
// linguistic equivalence relation. In a well-typed program, the
|
||||
// types of x and y are guaranteed equal.
|
||||
func equals(x, y value) bool {
|
||||
switch x := x.(type) {
|
||||
case bool:
|
||||
return x == y.(bool)
|
||||
case int:
|
||||
return x == y.(int)
|
||||
case int8:
|
||||
return x == y.(int8)
|
||||
case int16:
|
||||
return x == y.(int16)
|
||||
case int32:
|
||||
return x == y.(int32)
|
||||
case int64:
|
||||
return x == y.(int64)
|
||||
case uint:
|
||||
return x == y.(uint)
|
||||
case uint8:
|
||||
return x == y.(uint8)
|
||||
case uint16:
|
||||
return x == y.(uint16)
|
||||
case uint32:
|
||||
return x == y.(uint32)
|
||||
case uint64:
|
||||
return x == y.(uint64)
|
||||
case uintptr:
|
||||
return x == y.(uintptr)
|
||||
case float32:
|
||||
return x == y.(float32)
|
||||
case float64:
|
||||
return x == y.(float64)
|
||||
case complex64:
|
||||
return x == y.(complex64)
|
||||
case complex128:
|
||||
return x == y.(complex128)
|
||||
case string:
|
||||
return x == y.(string)
|
||||
case *value:
|
||||
return x == y.(*value)
|
||||
case chan value:
|
||||
return x == y.(chan value)
|
||||
case structure:
|
||||
return x.eq(y)
|
||||
case array:
|
||||
return x.eq(y)
|
||||
case iface:
|
||||
return x.eq(y)
|
||||
case rtype:
|
||||
return x.eq(y)
|
||||
|
||||
// Since the following types don't support comparison,
|
||||
// these cases are only reachable if one of x or y is
|
||||
// (literally) nil.
|
||||
case *hashmap:
|
||||
return x == y.(*hashmap)
|
||||
case map[value]value:
|
||||
return (x != nil) == (y.(map[value]value) != nil)
|
||||
case *ssa.Function:
|
||||
return x == y.(*ssa.Function)
|
||||
case *closure:
|
||||
return x == y.(*closure)
|
||||
case []value:
|
||||
return (x != nil) == (y.([]value) != nil)
|
||||
}
|
||||
panic(fmt.Sprintf("comparing incomparable type %T", x))
|
||||
}
|
||||
|
||||
// Returns an integer hash of x such that equals(x, y) => hash(x) == hash(y).
|
||||
func hash(x value) int {
|
||||
switch x := x.(type) {
|
||||
case bool:
|
||||
if x {
|
||||
return 1
|
||||
}
|
||||
return 0
|
||||
case int:
|
||||
return x
|
||||
case int8:
|
||||
return int(x)
|
||||
case int16:
|
||||
return int(x)
|
||||
case int32:
|
||||
return int(x)
|
||||
case int64:
|
||||
return int(x)
|
||||
case uint:
|
||||
return int(x)
|
||||
case uint8:
|
||||
return int(x)
|
||||
case uint16:
|
||||
return int(x)
|
||||
case uint32:
|
||||
return int(x)
|
||||
case uint64:
|
||||
return int(x)
|
||||
case uintptr:
|
||||
return int(x)
|
||||
case float32:
|
||||
return int(x)
|
||||
case float64:
|
||||
return int(x)
|
||||
case complex64:
|
||||
return int(real(x))
|
||||
case complex128:
|
||||
return int(real(x))
|
||||
case string:
|
||||
return hashString(x)
|
||||
case *value:
|
||||
return int(uintptr(unsafe.Pointer(x)))
|
||||
case chan value:
|
||||
return int(uintptr(reflect.ValueOf(x).Pointer()))
|
||||
case structure:
|
||||
return x.hash()
|
||||
case array:
|
||||
return x.hash()
|
||||
case iface:
|
||||
return x.hash()
|
||||
case rtype:
|
||||
return x.hash()
|
||||
}
|
||||
panic(fmt.Sprintf("%T is unhashable", x))
|
||||
}
|
||||
|
||||
// copyVal returns a copy of value v.
|
||||
// TODO(adonovan): add tests of aliasing and mutation.
|
||||
func copyVal(v value) value {
|
||||
if v == nil {
|
||||
panic("copyVal(nil)")
|
||||
}
|
||||
switch v := v.(type) {
|
||||
case bool, int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64, uintptr, float32, float64, complex64, complex128, string, unsafe.Pointer:
|
||||
return v
|
||||
case map[value]value:
|
||||
return v
|
||||
case *hashmap:
|
||||
return v
|
||||
case chan value:
|
||||
return v
|
||||
case *value:
|
||||
return v
|
||||
case *ssa.Function, *ssa.Builtin, *closure:
|
||||
return v
|
||||
case iface:
|
||||
return v
|
||||
case []value:
|
||||
return v
|
||||
case structure:
|
||||
a := make(structure, len(v))
|
||||
copy(a, v)
|
||||
return a
|
||||
case array:
|
||||
a := make(array, len(v))
|
||||
copy(a, v)
|
||||
return a
|
||||
case tuple:
|
||||
break
|
||||
case rtype:
|
||||
return v
|
||||
}
|
||||
panic(fmt.Sprintf("cannot copy %T", v))
|
||||
}
|
||||
|
||||
// Prints in the style of built-in println.
|
||||
// (More or less; in gc println is actually a compiler intrinsic and
|
||||
// can distinguish println(1) from println(interface{}(1)).)
|
||||
func toWriter(w io.Writer, v value) {
|
||||
switch v := v.(type) {
|
||||
case nil, bool, int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64, uintptr, float32, float64, complex64, complex128, string:
|
||||
fmt.Fprintf(w, "%v", v)
|
||||
|
||||
case map[value]value:
|
||||
io.WriteString(w, "map[")
|
||||
sep := " "
|
||||
for k, e := range v {
|
||||
io.WriteString(w, sep)
|
||||
sep = " "
|
||||
toWriter(w, k)
|
||||
io.WriteString(w, ":")
|
||||
toWriter(w, e)
|
||||
}
|
||||
io.WriteString(w, "]")
|
||||
|
||||
case *hashmap:
|
||||
io.WriteString(w, "map[")
|
||||
sep := " "
|
||||
for _, e := range v.table {
|
||||
for e != nil {
|
||||
io.WriteString(w, sep)
|
||||
sep = " "
|
||||
toWriter(w, e.key)
|
||||
io.WriteString(w, ":")
|
||||
toWriter(w, e.value)
|
||||
e = e.next
|
||||
}
|
||||
}
|
||||
io.WriteString(w, "]")
|
||||
|
||||
case chan value:
|
||||
fmt.Fprintf(w, "%v", v) // (an address)
|
||||
|
||||
case *value:
|
||||
if v == nil {
|
||||
io.WriteString(w, "<nil>")
|
||||
} else {
|
||||
fmt.Fprintf(w, "%p", v)
|
||||
}
|
||||
|
||||
case iface:
|
||||
toWriter(w, v.v)
|
||||
|
||||
case structure:
|
||||
io.WriteString(w, "{")
|
||||
for i, e := range v {
|
||||
if i > 0 {
|
||||
io.WriteString(w, " ")
|
||||
}
|
||||
toWriter(w, e)
|
||||
}
|
||||
io.WriteString(w, "}")
|
||||
|
||||
case array:
|
||||
io.WriteString(w, "[")
|
||||
for i, e := range v {
|
||||
if i > 0 {
|
||||
io.WriteString(w, " ")
|
||||
}
|
||||
toWriter(w, e)
|
||||
}
|
||||
io.WriteString(w, "]")
|
||||
|
||||
case []value:
|
||||
io.WriteString(w, "[")
|
||||
for i, e := range v {
|
||||
if i > 0 {
|
||||
io.WriteString(w, " ")
|
||||
}
|
||||
toWriter(w, e)
|
||||
}
|
||||
io.WriteString(w, "]")
|
||||
|
||||
case *ssa.Function, *ssa.Builtin, *closure:
|
||||
fmt.Fprintf(w, "%p", v) // (an address)
|
||||
|
||||
case rtype:
|
||||
io.WriteString(w, v.t.String())
|
||||
|
||||
case tuple:
|
||||
// Unreachable in well-formed Go programs
|
||||
io.WriteString(w, "(")
|
||||
for i, e := range v {
|
||||
if i > 0 {
|
||||
io.WriteString(w, ", ")
|
||||
}
|
||||
toWriter(w, e)
|
||||
}
|
||||
io.WriteString(w, ")")
|
||||
|
||||
default:
|
||||
fmt.Fprintf(w, "<%T>", v)
|
||||
}
|
||||
}
|
||||
|
||||
// Implements printing of Go values in the style of built-in println.
|
||||
func toString(v value) string {
|
||||
var b bytes.Buffer
|
||||
toWriter(&b, v)
|
||||
return b.String()
|
||||
}
|
||||
|
||||
// ------------------------------------------------------------------------
|
||||
// Iterators
|
||||
|
||||
type arrayIter struct {
|
||||
a array
|
||||
i int
|
||||
}
|
||||
|
||||
func (it *arrayIter) next() tuple {
|
||||
okv := make(tuple, 3)
|
||||
ok := it.i < len(it.a)
|
||||
okv[0] = ok
|
||||
if ok {
|
||||
okv[1] = it.i
|
||||
okv[2] = copyVal(it.a[it.i])
|
||||
}
|
||||
it.i++
|
||||
return okv
|
||||
}
|
||||
|
||||
type chanIter chan value
|
||||
|
||||
func (it chanIter) next() tuple {
|
||||
okv := make(tuple, 3)
|
||||
okv[1], okv[0] = <-it
|
||||
return okv
|
||||
}
|
||||
|
||||
type stringIter struct {
|
||||
*strings.Reader
|
||||
i int
|
||||
}
|
||||
|
||||
func (it *stringIter) next() tuple {
|
||||
okv := make(tuple, 3)
|
||||
ch, n, err := it.ReadRune()
|
||||
ok := err != io.EOF
|
||||
okv[0] = ok
|
||||
if ok {
|
||||
okv[1] = it.i
|
||||
okv[2] = ch
|
||||
}
|
||||
it.i += n
|
||||
return okv
|
||||
}
|
||||
|
||||
type mapIter chan [2]value
|
||||
|
||||
func (it mapIter) next() tuple {
|
||||
kv, ok := <-it
|
||||
return tuple{ok, kv[0], kv[1]}
|
||||
}
|
||||
121
src/pkg/exp/ssa/ssadump.go
Normal file
121
src/pkg/exp/ssa/ssadump.go
Normal file
@ -0,0 +1,121 @@
|
||||
// +build ignore
|
||||
|
||||
package main
|
||||
|
||||
// ssadump: a tool for displaying and interpreting the SSA form of Go programs.
|
||||
|
||||
import (
|
||||
"exp/ssa"
|
||||
"exp/ssa/interp"
|
||||
"flag"
|
||||
"fmt"
|
||||
"log"
|
||||
"os"
|
||||
"strings"
|
||||
)
|
||||
|
||||
// TODO(adonovan): perhaps these should each be separate flags?
|
||||
var buildFlag = flag.String("build", "", `Options controlling the SSA builder.
|
||||
The value is a sequence of zero or more of these letters:
|
||||
C perform sanity [C]hecking of the SSA form.
|
||||
P log [P]ackage inventory.
|
||||
F log [F]unction SSA code.
|
||||
S log [S]ource locations as SSA builder progresses.
|
||||
G use binary object files from gc to provide imports (no code).
|
||||
`)
|
||||
|
||||
var runFlag = flag.Bool("run", false, "Invokes the SSA interpreter on the program.")
|
||||
|
||||
var interpFlag = flag.String("interp", "", `Options controlling the SSA test interpreter.
|
||||
The value is a sequence of zero or more more of these letters:
|
||||
R disable [R]ecover() from panic; show interpreter crash instead.
|
||||
T [T]race execution of the program. Best for single-threaded programs!
|
||||
`)
|
||||
|
||||
const usage = `SSA builder and interpreter.
|
||||
Usage: ssadump [<flag> ...] <file.go> ...
|
||||
Use -help flag to display options.
|
||||
|
||||
Examples:
|
||||
% ssadump -run -interp=T hello.go # interpret a program, with tracing
|
||||
% ssadump -build=FPG hello.go # quickly dump SSA form of a single package
|
||||
`
|
||||
|
||||
func main() {
|
||||
flag.Parse()
|
||||
args := flag.Args()
|
||||
|
||||
// TODO(adonovan): perhaps we need a more extensible option
|
||||
// API than a bitset, e.g. a struct with a sane zero value?
|
||||
var mode ssa.BuilderMode
|
||||
for _, c := range *buildFlag {
|
||||
switch c {
|
||||
case 'P':
|
||||
mode |= ssa.LogPackages
|
||||
case 'F':
|
||||
mode |= ssa.LogFunctions
|
||||
case 'S':
|
||||
mode |= ssa.LogSource
|
||||
case 'C':
|
||||
mode |= ssa.SanityCheckFunctions
|
||||
case 'G':
|
||||
mode |= ssa.UseGCImporter
|
||||
default:
|
||||
log.Fatalf("Unknown -build option: '%c'.", c)
|
||||
}
|
||||
}
|
||||
|
||||
var interpMode interp.Mode
|
||||
for _, c := range *interpFlag {
|
||||
switch c {
|
||||
case 'T':
|
||||
interpMode |= interp.EnableTracing
|
||||
case 'R':
|
||||
interpMode |= interp.DisableRecover
|
||||
default:
|
||||
log.Fatalf("Unknown -interp option: '%c'.", c)
|
||||
}
|
||||
}
|
||||
|
||||
if len(args) == 0 {
|
||||
fmt.Fprint(os.Stderr, usage)
|
||||
os.Exit(1)
|
||||
}
|
||||
|
||||
// Treat all leading consecutive "*.go" arguments as a single package.
|
||||
//
|
||||
// TODO(gri): make it a typechecker error for there to be
|
||||
// duplicate (e.g.) main functions in the same package.
|
||||
var gofiles []string
|
||||
for len(args) > 0 && strings.HasSuffix(args[0], ".go") {
|
||||
gofiles = append(gofiles, args[0])
|
||||
args = args[1:]
|
||||
}
|
||||
if gofiles == nil {
|
||||
log.Fatal("No *.go source files specified.")
|
||||
}
|
||||
|
||||
// TODO(adonovan): permit naming a package directly instead of
|
||||
// a list of .go files.
|
||||
|
||||
// TODO(adonovan/gri): the cascade of errors is confusing due
|
||||
// to reentrant control flow. Disable for now and re-think.
|
||||
var errh func(error)
|
||||
// errh = func(err error) { fmt.Println(err.Error()) }
|
||||
|
||||
b := ssa.NewBuilder(mode, ssa.GorootLoader, errh)
|
||||
files, err := ssa.ParseFiles(b.Prog.Files, ".", gofiles...)
|
||||
if err != nil {
|
||||
log.Fatalf(err.Error())
|
||||
}
|
||||
mainpkg, err := b.CreatePackage("main", files)
|
||||
if err != nil {
|
||||
log.Fatalf(err.Error())
|
||||
}
|
||||
b.BuildPackage(mainpkg)
|
||||
b = nil // discard Builder
|
||||
|
||||
if *runFlag {
|
||||
interp.Interpret(mainpkg, interpMode, gofiles[0], args)
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user