code: func appendSleb128(b []byte, v int64) []byte {
  	for {
  		c := uint8(v & 0x7f)
  		s := uint8(v & 0x40)
  		v >>= 7
  		if (v != -1 || s == 0) && (v != 0 || s != 0) {
  			c |= 0x80
  		}
  		b = append(b, c)
  		if c&0x80 == 0 {
  			break
  		}
  	}
  	return b
  }
docs: // appendSleb128 appends v to b using DWARF's signed LEB128 encoding.