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verified gcc-4.6.4.tar.bz2.sig;
imported gcc-4.6.4 source tree from verified upstream tarball.

downloading a git-generated archive based on the 'upstream' tag
should provide you with a source tree that is binary identical
to the one extracted from the above tarball.

if you have obtained the source via the command 'git clone',
however, do note that line-endings of files in your working
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1 files changed, 573 insertions, 0 deletions

diff --git a/libgo/go/gob/encode.go b/libgo/go/gob/encode.go
new file mode 100644
index 000000000..d286a7e00
--- /dev/null
+++ b/libgo/go/gob/encode.go
@@ -0,0 +1,573 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gob
+
+import (
+	"bytes"
+	"io"
+	"math"
+	"os"
+	"reflect"
+	"unsafe"
+)
+
+const uint64Size = unsafe.Sizeof(uint64(0))
+
+// The global execution state of an instance of the encoder.
+// Field numbers are delta encoded and always increase. The field
+// number is initialized to -1 so 0 comes out as delta(1). A delta of
+// 0 terminates the structure.
+type encoderState struct {
+	enc      *Encoder
+	b        *bytes.Buffer
+	sendZero bool                 // encoding an array element or map key/value pair; send zero values
+	fieldnum int                  // the last field number written.
+	buf      [1 + uint64Size]byte // buffer used by the encoder; here to avoid allocation.
+}
+
+func newEncoderState(enc *Encoder, b *bytes.Buffer) *encoderState {
+	return &encoderState{enc: enc, b: b}
+}
+
+// Unsigned integers have a two-state encoding.  If the number is less
+// than 128 (0 through 0x7F), its value is written directly.
+// Otherwise the value is written in big-endian byte order preceded
+// by the byte length, negated.
+
+// encodeUint writes an encoded unsigned integer to state.b.
+func (state *encoderState) encodeUint(x uint64) {
+	if x <= 0x7F {
+		err := state.b.WriteByte(uint8(x))
+		if err != nil {
+			error(err)
+		}
+		return
+	}
+	var n, m int
+	m = uint64Size
+	for n = 1; x > 0; n++ {
+		state.buf[m] = uint8(x & 0xFF)
+		x >>= 8
+		m--
+	}
+	state.buf[m] = uint8(-(n - 1))
+	n, err := state.b.Write(state.buf[m : uint64Size+1])
+	if err != nil {
+		error(err)
+	}
+}
+
+// encodeInt writes an encoded signed integer to state.w.
+// The low bit of the encoding says whether to bit complement the (other bits of the)
+// uint to recover the int.
+func (state *encoderState) encodeInt(i int64) {
+	var x uint64
+	if i < 0 {
+		x = uint64(^i<<1) | 1
+	} else {
+		x = uint64(i << 1)
+	}
+	state.encodeUint(uint64(x))
+}
+
+type encOp func(i *encInstr, state *encoderState, p unsafe.Pointer)
+
+// The 'instructions' of the encoding machine
+type encInstr struct {
+	op     encOp
+	field  int     // field number
+	indir  int     // how many pointer indirections to reach the value in the struct
+	offset uintptr // offset in the structure of the field to encode
+}
+
+// Emit a field number and update the state to record its value for delta encoding.
+// If the instruction pointer is nil, do nothing
+func (state *encoderState) update(instr *encInstr) {
+	if instr != nil {
+		state.encodeUint(uint64(instr.field - state.fieldnum))
+		state.fieldnum = instr.field
+	}
+}
+
+// Each encoder is responsible for handling any indirections associated
+// with the data structure.  If any pointer so reached is nil, no bytes are written.
+// If the data item is zero, no bytes are written.
+// Otherwise, the output (for a scalar) is the field number, as an encoded integer,
+// followed by the field data in its appropriate format.
+
+func encIndirect(p unsafe.Pointer, indir int) unsafe.Pointer {
+	for ; indir > 0; indir-- {
+		p = *(*unsafe.Pointer)(p)
+		if p == nil {
+			return unsafe.Pointer(nil)
+		}
+	}
+	return p
+}
+
+func encBool(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	b := *(*bool)(p)
+	if b || state.sendZero {
+		state.update(i)
+		if b {
+			state.encodeUint(1)
+		} else {
+			state.encodeUint(0)
+		}
+	}
+}
+
+func encInt(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := int64(*(*int)(p))
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeInt(v)
+	}
+}
+
+func encUint(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := uint64(*(*uint)(p))
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeUint(v)
+	}
+}
+
+func encInt8(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := int64(*(*int8)(p))
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeInt(v)
+	}
+}
+
+func encUint8(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := uint64(*(*uint8)(p))
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeUint(v)
+	}
+}
+
+func encInt16(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := int64(*(*int16)(p))
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeInt(v)
+	}
+}
+
+func encUint16(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := uint64(*(*uint16)(p))
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeUint(v)
+	}
+}
+
+func encInt32(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := int64(*(*int32)(p))
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeInt(v)
+	}
+}
+
+func encUint32(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := uint64(*(*uint32)(p))
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeUint(v)
+	}
+}
+
+func encInt64(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := *(*int64)(p)
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeInt(v)
+	}
+}
+
+func encUint64(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := *(*uint64)(p)
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeUint(v)
+	}
+}
+
+func encUintptr(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	v := uint64(*(*uintptr)(p))
+	if v != 0 || state.sendZero {
+		state.update(i)
+		state.encodeUint(v)
+	}
+}
+
+// Floating-point numbers are transmitted as uint64s holding the bits
+// of the underlying representation.  They are sent byte-reversed, with
+// the exponent end coming out first, so integer floating point numbers
+// (for example) transmit more compactly.  This routine does the
+// swizzling.
+func floatBits(f float64) uint64 {
+	u := math.Float64bits(f)
+	var v uint64
+	for i := 0; i < 8; i++ {
+		v <<= 8
+		v |= u & 0xFF
+		u >>= 8
+	}
+	return v
+}
+
+func encFloat32(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	f := *(*float32)(p)
+	if f != 0 || state.sendZero {
+		v := floatBits(float64(f))
+		state.update(i)
+		state.encodeUint(v)
+	}
+}
+
+func encFloat64(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	f := *(*float64)(p)
+	if f != 0 || state.sendZero {
+		state.update(i)
+		v := floatBits(f)
+		state.encodeUint(v)
+	}
+}
+
+// Complex numbers are just a pair of floating-point numbers, real part first.
+func encComplex64(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	c := *(*complex64)(p)
+	if c != 0+0i || state.sendZero {
+		rpart := floatBits(float64(real(c)))
+		ipart := floatBits(float64(imag(c)))
+		state.update(i)
+		state.encodeUint(rpart)
+		state.encodeUint(ipart)
+	}
+}
+
+func encComplex128(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	c := *(*complex128)(p)
+	if c != 0+0i || state.sendZero {
+		rpart := floatBits(real(c))
+		ipart := floatBits(imag(c))
+		state.update(i)
+		state.encodeUint(rpart)
+		state.encodeUint(ipart)
+	}
+}
+
+func encNoOp(i *encInstr, state *encoderState, p unsafe.Pointer) {
+}
+
+// Byte arrays are encoded as an unsigned count followed by the raw bytes.
+func encUint8Array(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	b := *(*[]byte)(p)
+	if len(b) > 0 || state.sendZero {
+		state.update(i)
+		state.encodeUint(uint64(len(b)))
+		state.b.Write(b)
+	}
+}
+
+// Strings are encoded as an unsigned count followed by the raw bytes.
+func encString(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	s := *(*string)(p)
+	if len(s) > 0 || state.sendZero {
+		state.update(i)
+		state.encodeUint(uint64(len(s)))
+		io.WriteString(state.b, s)
+	}
+}
+
+// The end of a struct is marked by a delta field number of 0.
+func encStructTerminator(i *encInstr, state *encoderState, p unsafe.Pointer) {
+	state.encodeUint(0)
+}
+
+// Execution engine
+
+// The encoder engine is an array of instructions indexed by field number of the encoding
+// data, typically a struct.  It is executed top to bottom, walking the struct.
+type encEngine struct {
+	instr []encInstr
+}
+
+const singletonField = 0
+
+func (enc *Encoder) encodeSingle(b *bytes.Buffer, engine *encEngine, basep uintptr) {
+	state := newEncoderState(enc, b)
+	state.fieldnum = singletonField
+	// There is no surrounding struct to frame the transmission, so we must
+	// generate data even if the item is zero.  To do this, set sendZero.
+	state.sendZero = true
+	instr := &engine.instr[singletonField]
+	p := unsafe.Pointer(basep) // offset will be zero
+	if instr.indir > 0 {
+		if p = encIndirect(p, instr.indir); p == nil {
+			return
+		}
+	}
+	instr.op(instr, state, p)
+}
+
+func (enc *Encoder) encodeStruct(b *bytes.Buffer, engine *encEngine, basep uintptr) {
+	state := newEncoderState(enc, b)
+	state.fieldnum = -1
+	for i := 0; i < len(engine.instr); i++ {
+		instr := &engine.instr[i]
+		p := unsafe.Pointer(basep + instr.offset)
+		if instr.indir > 0 {
+			if p = encIndirect(p, instr.indir); p == nil {
+				continue
+			}
+		}
+		instr.op(instr, state, p)
+	}
+}
+
+func (enc *Encoder) encodeArray(b *bytes.Buffer, p uintptr, op encOp, elemWid uintptr, elemIndir int, length int) {
+	state := newEncoderState(enc, b)
+	state.fieldnum = -1
+	state.sendZero = true
+	state.encodeUint(uint64(length))
+	for i := 0; i < length; i++ {
+		elemp := p
+		up := unsafe.Pointer(elemp)
+		if elemIndir > 0 {
+			if up = encIndirect(up, elemIndir); up == nil {
+				errorf("gob: encodeArray: nil element")
+			}
+			elemp = uintptr(up)
+		}
+		op(nil, state, unsafe.Pointer(elemp))
+		p += uintptr(elemWid)
+	}
+}
+
+func encodeReflectValue(state *encoderState, v reflect.Value, op encOp, indir int) {
+	for i := 0; i < indir && v != nil; i++ {
+		v = reflect.Indirect(v)
+	}
+	if v == nil {
+		errorf("gob: encodeReflectValue: nil element")
+	}
+	op(nil, state, unsafe.Pointer(v.Addr()))
+}
+
+func (enc *Encoder) encodeMap(b *bytes.Buffer, mv *reflect.MapValue, keyOp, elemOp encOp, keyIndir, elemIndir int) {
+	state := newEncoderState(enc, b)
+	state.fieldnum = -1
+	state.sendZero = true
+	keys := mv.Keys()
+	state.encodeUint(uint64(len(keys)))
+	for _, key := range keys {
+		encodeReflectValue(state, key, keyOp, keyIndir)
+		encodeReflectValue(state, mv.Elem(key), elemOp, elemIndir)
+	}
+}
+
+// To send an interface, we send a string identifying the concrete type, followed
+// by the type identifier (which might require defining that type right now), followed
+// by the concrete value.  A nil value gets sent as the empty string for the name,
+// followed by no value.
+func (enc *Encoder) encodeInterface(b *bytes.Buffer, iv *reflect.InterfaceValue) {
+	state := newEncoderState(enc, b)
+	state.fieldnum = -1
+	state.sendZero = true
+	if iv.IsNil() {
+		state.encodeUint(0)
+		return
+	}
+
+	typ, _ := indirect(iv.Elem().Type())
+	name, ok := concreteTypeToName[typ]
+	if !ok {
+		errorf("gob: type not registered for interface: %s", typ)
+	}
+	// Send the name.
+	state.encodeUint(uint64(len(name)))
+	_, err := io.WriteString(state.b, name)
+	if err != nil {
+		error(err)
+	}
+	// Send (and maybe first define) the type id.
+	enc.sendTypeDescriptor(typ)
+	// Encode the value into a new buffer.
+	data := new(bytes.Buffer)
+	err = enc.encode(data, iv.Elem())
+	if err != nil {
+		error(err)
+	}
+	state.encodeUint(uint64(data.Len()))
+	_, err = state.b.Write(data.Bytes())
+	if err != nil {
+		error(err)
+	}
+}
+
+var encOpMap = []encOp{
+	reflect.Bool:       encBool,
+	reflect.Int:        encInt,
+	reflect.Int8:       encInt8,
+	reflect.Int16:      encInt16,
+	reflect.Int32:      encInt32,
+	reflect.Int64:      encInt64,
+	reflect.Uint:       encUint,
+	reflect.Uint8:      encUint8,
+	reflect.Uint16:     encUint16,
+	reflect.Uint32:     encUint32,
+	reflect.Uint64:     encUint64,
+	reflect.Uintptr:    encUintptr,
+	reflect.Float32:    encFloat32,
+	reflect.Float64:    encFloat64,
+	reflect.Complex64:  encComplex64,
+	reflect.Complex128: encComplex128,
+	reflect.String:     encString,
+}
+
+// Return the encoding op for the base type under rt and
+// the indirection count to reach it.
+func (enc *Encoder) encOpFor(rt reflect.Type) (encOp, int) {
+	typ, indir := indirect(rt)
+	var op encOp
+	k := typ.Kind()
+	if int(k) < len(encOpMap) {
+		op = encOpMap[k]
+	}
+	if op == nil {
+		// Special cases
+		switch t := typ.(type) {
+		case *reflect.SliceType:
+			if t.Elem().Kind() == reflect.Uint8 {
+				op = encUint8Array
+				break
+			}
+			// Slices have a header; we decode it to find the underlying array.
+			elemOp, indir := enc.encOpFor(t.Elem())
+			op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
+				slice := (*reflect.SliceHeader)(p)
+				if !state.sendZero && slice.Len == 0 {
+					return
+				}
+				state.update(i)
+				state.enc.encodeArray(state.b, slice.Data, elemOp, t.Elem().Size(), indir, int(slice.Len))
+			}
+		case *reflect.ArrayType:
+			// True arrays have size in the type.
+			elemOp, indir := enc.encOpFor(t.Elem())
+			op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
+				state.update(i)
+				state.enc.encodeArray(state.b, uintptr(p), elemOp, t.Elem().Size(), indir, t.Len())
+			}
+		case *reflect.MapType:
+			keyOp, keyIndir := enc.encOpFor(t.Key())
+			elemOp, elemIndir := enc.encOpFor(t.Elem())
+			op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
+				// Maps cannot be accessed by moving addresses around the way
+				// that slices etc. can.  We must recover a full reflection value for
+				// the iteration.
+				v := reflect.NewValue(unsafe.Unreflect(t, unsafe.Pointer((p))))
+				mv := reflect.Indirect(v).(*reflect.MapValue)
+				if !state.sendZero && mv.Len() == 0 {
+					return
+				}
+				state.update(i)
+				state.enc.encodeMap(state.b, mv, keyOp, elemOp, keyIndir, elemIndir)
+			}
+		case *reflect.StructType:
+			// Generate a closure that calls out to the engine for the nested type.
+			enc.getEncEngine(typ)
+			info := mustGetTypeInfo(typ)
+			op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
+				state.update(i)
+				// indirect through info to delay evaluation for recursive structs
+				state.enc.encodeStruct(state.b, info.encoder, uintptr(p))
+			}
+		case *reflect.InterfaceType:
+			op = func(i *encInstr, state *encoderState, p unsafe.Pointer) {
+				// Interfaces transmit the name and contents of the concrete
+				// value they contain.
+				v := reflect.NewValue(unsafe.Unreflect(t, unsafe.Pointer((p))))
+				iv := reflect.Indirect(v).(*reflect.InterfaceValue)
+				if !state.sendZero && (iv == nil || iv.IsNil()) {
+					return
+				}
+				state.update(i)
+				state.enc.encodeInterface(state.b, iv)
+			}
+		}
+	}
+	if op == nil {
+		errorf("gob enc: can't happen: encode type %s", rt.String())
+	}
+	return op, indir
+}
+
+// The local Type was compiled from the actual value, so we know it's compatible.
+func (enc *Encoder) compileEnc(rt reflect.Type) *encEngine {
+	srt, isStruct := rt.(*reflect.StructType)
+	engine := new(encEngine)
+	if isStruct {
+		engine.instr = make([]encInstr, srt.NumField()+1) // +1 for terminator
+		for fieldnum := 0; fieldnum < srt.NumField(); fieldnum++ {
+			f := srt.Field(fieldnum)
+			op, indir := enc.encOpFor(f.Type)
+			if !isExported(f.Name) {
+				op = encNoOp
+			}
+			engine.instr[fieldnum] = encInstr{op, fieldnum, indir, uintptr(f.Offset)}
+		}
+		engine.instr[srt.NumField()] = encInstr{encStructTerminator, 0, 0, 0}
+	} else {
+		engine.instr = make([]encInstr, 1)
+		op, indir := enc.encOpFor(rt)
+		engine.instr[0] = encInstr{op, singletonField, indir, 0} // offset is zero
+	}
+	return engine
+}
+
+// typeLock must be held (or we're in initialization and guaranteed single-threaded).
+// The reflection type must have all its indirections processed out.
+func (enc *Encoder) getEncEngine(rt reflect.Type) *encEngine {
+	info, err1 := getTypeInfo(rt)
+	if err1 != nil {
+		error(err1)
+	}
+	if info.encoder == nil {
+		// mark this engine as underway before compiling to handle recursive types.
+		info.encoder = new(encEngine)
+		info.encoder = enc.compileEnc(rt)
+	}
+	return info.encoder
+}
+
+// Put this in a function so we can hold the lock only while compiling, not when encoding.
+func (enc *Encoder) lockAndGetEncEngine(rt reflect.Type) *encEngine {
+	typeLock.Lock()
+	defer typeLock.Unlock()
+	return enc.getEncEngine(rt)
+}
+
+func (enc *Encoder) encode(b *bytes.Buffer, value reflect.Value) (err os.Error) {
+	defer catchError(&err)
+	// Dereference down to the underlying object.
+	rt, indir := indirect(value.Type())
+	for i := 0; i < indir; i++ {
+		value = reflect.Indirect(value)
+	}
+	engine := enc.lockAndGetEncEngine(rt)
+	if value.Type().Kind() == reflect.Struct {
+		enc.encodeStruct(b, engine, value.Addr())
+	} else {
+		enc.encodeSingle(b, engine, value.Addr())
+	}
+	return nil
+}