compressedSize = (int(data[off+1]) >> 2) | (int(data[off+2]) << 6)
		off += 3
		streams = 4
	case 3:
		if off+3 >= len(data) {
			return 0, nil, r.makeEOFError(off)
		}
		regeneratedSize = (int(hdr) >> 4) | (int(data[off]) << 4) | ((int(data[off+1]) & 0x3f) << 12)
		compressedSize = (int(data[off+1]) >> 6) | (int(data[off+2]) << 2) | (int(data[off+3]) << 10)
		off += 4

		off++
	} else {
		if off+1 >= len(data) {
			return 0, 0, r.makeEOFError(off)
		}
		seqCount = int(data[off]) + (int(data[off+1]) << 8) + 0x7f00
		off += 2
	}

	// Read the Symbol_Compression_Modes byte.

	if off >= len(data) {
		return 0, 0, r.makeEOFError(off)
	}
	symMode := data[off]
	if symMode&3 != 0 {
		return 0, 0, r.makeError(off, "invalid symbol compression mode")
	}
	off++

(MOVBstore [off] {sym} ptr y:(SETNE x) mem) && y.Uses == 1 => (SETNEstore [off] {sym} ptr x mem)
(MOVBstore [off] {sym} ptr y:(SETB x) mem) && y.Uses == 1 => (SETBstore [off] {sym} ptr x mem)
(MOVBstore [off] {sym} ptr y:(SETBE x) mem) && y.Uses == 1 => (SETBEstore [off] {sym} ptr x mem)
(MOVBstore [off] {sym} ptr y:(SETA x) mem) && y.Uses == 1 => (SETAstore [off] {sym} ptr x mem)

// on future calls with the same type t.
func Set(t *types.Type, off int64, bv bitvec.BitVec) {
	set(t, off, bv, false)
}

// SetNoCheck is like Set, but do not check for alignment.
func SetNoCheck(t *types.Type, off int64, bv bitvec.BitVec) {
	set(t, off, bv, true)
}

func set(t *types.Type, off int64, bv bitvec.BitVec, skip bool) {
	if !skip && uint8(t.Alignment()) > 0 && off&int64(uint8(t.Alignment())-1) != 0 {

// pointer value. The src pointer is off bytes into the gcbits.
//
//go:nosplit
//go:nowritebarrier
func cgoCheckBits(src unsafe.Pointer, gcbits *byte, off, size uintptr) {
	skipMask := off / goarch.PtrSize / 8
	skipBytes := skipMask * goarch.PtrSize * 8
	ptrmask := addb(gcbits, skipMask)
	src = add(src, skipBytes)
	off -= skipBytes
	size += off
	var bits uint32

	if len == 0 {
		return nil
	}
	end := int(off) + len
	return r.b[int(off):end:end]
}

func (r *Reader) uint64At(off uint32) uint64 {
	b := r.BytesAt(off, 8)
	return binary.LittleEndian.Uint64(b)
}

func (r *Reader) int64At(off uint32) int64 {
	return int64(r.uint64At(off))
}

func (r *Reader) uint32At(off uint32) uint32 {
	b := r.BytesAt(off, 4)

	if len(buf) >= w.size {
		from := len(buf) - w.size
		w.data = append(w.data[:0], buf[from:]...)
		w.off = 0
		return
	}

	// Update off to point to the oldest remaining byte.
	free := w.size - len(w.data)
	if free == 0 {
		n := copy(w.data[w.off:], buf)
		if n == len(buf) {
			w.off += n
		} else {
			w.off = copy(w.data, buf[n:])
		}
	} else {
		if free >= len(buf) {
			w.data = append(w.data, buf...)

		off := header.SetUint(ctxt.Arch, 8, uint64(state.nfunc))
		off = header.SetUint(ctxt.Arch, off, uint64(state.nfiles))
		if off != textStartOff {
			panic(fmt.Sprintf("pcHeader textStartOff: %d != %d", off, textStartOff))
		}
		off += int64(ctxt.Arch.PtrSize) // skip runtimeText relocation
		off = writeSymOffset(off, state.funcnametab)
		off = writeSymOffset(off, state.cutab)

		is64, _ := b.format.dwarf64()
		if is64 {
			off *= 8
		} else {
			off *= 4
		}
		off += rnglistsBase
		if uint64(int(off)) != off {
			b.error("DW_FORM_rnglistx offset out of range")
		}

		b1 := makeBuf(b.dwarf, b.format, "rnglists", 0, b.dwarf.rngLists)
		b1.skip(int(off))
		if is64 {
			off = b1.uint64()
		} else {
			off = uint64(b1.uint32())
		}
		if b1.err != nil {
			b.err = b1.err

	)
}

func unpackUint32(msg []byte, off int) (uint32, int, error) {
	if off+uint32Len > len(msg) {
		return 0, off, errBaseLen
	}
	v := uint32(msg[off])<<24 | uint32(msg[off+1])<<16 | uint32(msg[off+2])<<8 | uint32(msg[off+3])
	return v, off + uint32Len, nil
}

func skipUint32(msg []byte, off int) (int, error) {
	if off+uint32Len > len(msg) {
		return off, errBaseLen
	}
	return off + uint32Len, nil