Method for accessing a memory unit in which sequences of notes are stored, corresponding memory unit and corresponding program
A method employs a bit sequence having a plurality of successive bits is stored in a write mode in a memory unit for a data value of a datum. The bit positions are each allocated to a data set which contains a data field for storing the datum. This measure enables logic operations to be carried out very rapidly.
1. A method to access a memory unit, comprising:
storing in a write mode of the memory unit a bit sequence comprising successive bit positions, each bit position having one of two bit values for a data value of a datum; and
allocating at least one of the bit positions to a data set comprising a data field to store the datum, wherein
one bit value in the bit sequence indicates that at least one of the bit positions allocated to the data set with one of the bit values comprises the data value in the data field to store the datum,
the other bit value in the bit sequence indicates that the at least one of the bit positions allocated to the data set with the other of the bit values excludes the data value in the data field to store the datum,
the method further comprises compressing the bit sequence by replacing successive data words where the one bit value occurs for a first number value that with two number values where a first number value indicates a number of words replaced, and
a second number value indicates a number of succeeding uncompressed data words.
2. The method as recited in claim 1 , further comprising:
reading at least a part of the bit sequence in a read mode.
3. The method as recited in claim 2 , wherein
the bit sequence comprises a greater number of the bit positions than bit positions in a data word of a processor accessing the memory unit, and
the bit sequence comprises several thousand, several hundred thousand or several million bit positions, to which are allocated several thousand, several hundred thousand or several million data sets.
4. The method as recited in claim 3 , further comprising:
linking two bit sequences according to a first logic operation, wherein the bit positions belonging to the same data set are linked, and the bit positions in one data word are processed simultaneously.
5. The method as recited in claim 4 , wherein the first logic operation comprises an OR function or an AND function.
6. The method as recited in claim 5 , further comprising:
simultaneously linking two bit sequences into the bit sequence according to a second logic operation.
7. The method as recited in claim 6 , wherein the second logic operation comprises a NOT function.
8. The method as recited in claim 7 , further comprising:
processing a bit sequence according to a third logic operation.
9. The method as recited in claim 8 , wherein the third logic operation comprises a NOT function.
10. The method as recited in claim 8 , wherein
the bit position in the bit sequence designates a number of the allocated data set, where the number is noted in the data set, or a memory address of the allocated data set is calculated from the number of the allocated data sets using a method that is the same for the data sets.
11. The method as recited in claim 10 , further comprising:
storing the bit sequence in memory areas of the same size, wherein
a sequence of references, with references to the memory areas, defines an order in which the bit sequence is stored in the memory areas.
12. The method as recited in claim 11 , further comprising:
monitoring the utilization of the memory areas; and
changing the utilization of other memory areas to incorporate a new memory area or to release the memory area.
13. The method as recited in claim 1 , wherein
the bit sequence comprises a greater number of the bit positions than bit positions in a data word of a processor accessing the memory unit, and
the bit sequence comprises several thousand, several hundred thousand or several million bit positions, to which are allocated several thousand, several hundred thousand or several million data sets.
14. The method as recited in claim 1 , further comprising:
linking two bit sequences according to a logic operation, wherein the bit positions belonging to the same data set are linked, and the bit positions in one data word are processed simultaneously.
15. The method as recited in claim 14 , wherein the logic operation comprises an OR function or an AND function.
16. The method as recited in claim 1 , further comprising:
simultaneously linking two bit sequences into the bit sequence according to a logic operation.
17. The method as recited in claim 16 , wherein the logic operation comprises a NOT function.
18. The method as recited in claim 1 , further comprising:
processing a bit sequence according to a logic operation.
19. The method as recited in claim 18 , wherein the logic operation comprises a NOT function.
20. The method as recited in claim 1 , wherein
the bit position in the bit sequence designates a number of the allocated data set, where the number is noted in the data set, or a memory address of the allocated data set is calculated from the number of the allocated data sets using a method that is the same for the data sets.
21. The method as recited in claim 1 , further comprising:
storing the bit sequence in memory areas of the same size, wherein
a sequence of references, with references to the memory areas, defines an order in which the bit sequence is stored in the memory areas.
22. The method as recited in claim 21 , further comprising:
monitoring the utilization of the memory areas; and
changing the utilization of other memory areas to incorporate a new memory area or to release the memory area.
23. A method to access a memory unit, comprising:
storing in a write mode of the memory unit a bit sequence comprising successive bit positions, each bit position having one of two bit values for a data value of a datum; and
allocating at least one of the bit positions to a data set comprising a data field to store the datum, wherein
one bit value in the bit sequence indicates that at least one of the bit positions allocated to the data set with one of the bit values comprises the data value in the data field to store the datum,
the other bit value in the bit sequence indicates that the at least one of the bit positions allocated to the data set with the other of the bit values excludes the data value in the data field to store the datum,
the method further comprises storing the bit sequence in memory areas of the same size,
a sequence of references, with references to the memory areas, defines an order in which the bit sequence is stored in the memory areas,
the method further comprises monitoring the utilization of the memory areas,
the method further comprises changing the utilization of other memory areas to incorporate a new memory area or to release the memory area,
when incorporating the new memory area to store a part of the bit sequence for which more than one third of the memory area is required, the part of the bit sequence is moved into the new memory area from another memory area, and
a reference to the new memory area is inserted into the sequence of references or appended to the sequence of references.
24. A method to access a memory unit, comprising:
storing in a write mode of the memory unit a bit sequence comprising successive bit positions, each bit position having one of two bit values for a data value of a datum; and
allocating at least one of the bit positions to a data set comprising a data field to store the datum, wherein
one bit value in the bit sequence indicates that at least one of the bit positions allocated to the data set with one of the bit values comprises the data value in the data field to store the datum,
the other bit value in the bit sequence indicates that the at least one of the bit positions allocated to the data set with the other of the bit values excludes the data value in the data field to store the datum,
the method further comprises storing the bit sequence in memory areas of the same size,
a sequence of references, with references to the memory areas, defines an order in which the bit sequence is stored in the memory areas,
the method further comprises:
monitoring the utilization of the memory areas;
changing the utilization of other memory areas to incorporate a new memory area or to release the memory area;
checking whether less than one third of the memory area is utilized by a part of the bit sequence stored therein;
checking whether a previous or subsequent memory area to the memory area in the sequence of references has sufficient space to accommodate the part of the bit sequence;
transferring the part of the bit sequence if there is sufficient space available; and
removing a reference to the memory area freed up from the sequence of references.