Unroll of instructions in a micro-controller

• US 5,828,875 A
• Filed: 05/29/1997
• Issued: 10/27/1998
• Est. Priority Date: 05/29/1997
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Jonsson, Tomas Lars, Roos, Tobias Carl, Lundstrom, Lars-Erik, Halvarsson, Dan Olov
• Primary Examiner(s): Treat, William M.
• Application Number:
  US08/864,888
• Time in Patent Office: 516 Days
• Field of Search: 395/588, 395/705
• US Class Current: 712/241
• CPC Class Codes: G06F 9/30145 Instruction analysis, e.g. decoding, instruction word fields
• CPC Class Codes: G06F 9/3017 Runtime instruction translation, e.g. macros
• CPC Class Codes: G06F 9/325 for loops, e.g. loop detection or loop counter

Abstract

Loops in program code are avoided by generating instructions for controlling a processor. A first template instruction is stored, and a predetermined number of instructions may be generated, wherein each generated instruction is based on the first template instruction. The processor may be alternatively supplied with the generated instructions or with instructions received from an alternative instruction source. A substitute address field may be stored, and the step of generating each instruction may include substituting the substitute address field in place of an address field in the first template instruction. The stored substitute address field may be adjusted after generating each instruction. The step substituting the substitute address field in place of an address field in the first template instruction may be performed only if a substitution control signal is asserted. In another embodiment, first and second template instructions are stored, and each is used as a basis for generating a repeating sequence of instructions, including first and second instructions.

Claims

1. An unroll apparatus for generating instructions for controlling a processor, the unroll apparatus comprising:

a first template storage means for storing a first template instruction;

a counter;

generating means for generating a number of instructions, wherein each generated instruction is based on the first template instruction;

means for adjusting the counter to indicate the number of instructions that have been generated by the generating means; and

means for deactivating the generating means in response to the counter indicating that a predetermined number of instructions have been generated.

2. The unroll apparatus of claim 1, further comprising:

means for supplying the generated instructions to the processor when the unroll apparatus is activated, and for supplying instructions received from an alternative instruction source to the processor when the unroll apparatus is not activated.

3. The unroll apparatus of claim 1, further comprising:

a substitute field storage means for storing a substitute address field, and wherein the generating means generates each generated instruction by substituting the substitute address field in place of an address field in the first template instruction.

4. The unroll apparatus of claim 3, further comprising:

means for adjusting the substitute address field in the substitute field storage means after generating each instruction.

5. The unroll apparatus of claim 3, further comprising:

means for storing a substitution control signal;

wherein the generating means substitutes the substitute address field in place of an address field in the first template instruction only if the substitution control signal is asserted.

6. The unroll apparatus of claim 1, further comprising:

means for receiving a signal that indicates satisfaction of a condition; and

means for deactivating the generating means in response to assertion of the signal that indicates satisfaction of the condition.

7. An unroll apparatus for generating instructions for controlling a processor, the unroll apparatus comprising:

a first template storage means for storing a first template instruction;

a second template storage means for storing a second template instruction;

a counter;

generating means for generating a number of instructions including a first instruction based on the first template instruction and a second instruction based on the second template instruction;

means for repeatedly operating the generating means;

means for adjusting the counter to indicate a number of instructions that have been generated by the generating means; and

means for deactivating the generating means in response to the counter indicating that a predetermined number of instructions have been generated.

8. The unroll apparatus of claim 7, further comprising:

means for supplying the generated instructions to the processor when the unroll apparatus is activated, and for supplying instructions received from an alternative instruction source to the processor when the unroll apparatus is not activated.

9. The unroll apparatus of claim 7, further comprising:

a substitute field storage means for storing a substitute address field, and

wherein the generating means generates each first instruction by substituting the substitute address field in place of an address field in the first template instruction.

10. The unroll apparatus of claim 9, further comprising:

means for adjusting the substitute address field in the substitute field storage means after generating each first instruction.

11. The unroll apparatus of claim 9, further comprising:

means for storing a first substitution control signal;

wherein the generating means substitutes the substitute address field in place of an address field in the first template instruction only if the first substitution control signal is asserted.

12. The unroll apparatus of claim 9, wherein:

the generating means generates each second instruction by substituting the substitute address field in place of an address field in the second template instruction.

13. The unroll apparatus of claim 12, further comprising:

means for adjusting the substitute address field in the substitute field storage means after generating each first instruction; and

means for adjusting the substitute address field in the substitute field storage means after generating each second instruction.

14. The unroll apparatus of claim 12, further comprising:

means for storing a first substitution control signal; and

means for storing a second substitution control signal,

wherein the generating means substitutes the substitute address field in place of an address field in the first template instruction only if the first substitution control signal is asserted, and wherein the generating means substitutes the substitute address field in place of an address field in the second template instruction only if the second substitution control signal is asserted.

15. The unroll apparatus of claim 7, further comprising:

means for receiving a signal that indicates satisfaction of a condition; and

means for deactivating the generating means in response to assertion of the signal that indicates satisfaction of the condition.

16. A method for generating instructions for controlling a processor, the method comprising the steps of:

storing a first template instruction;

using a generating apparatus to generate a predetermined number of instructions, wherein each generated instruction is based on the first template instruction.

17. The method of claim 16, further comprising the steps of:

supplying the generated instructions to the processor when the generating apparatus is activated; and

supplying instructions received from an alternative instruction source to the processor when the generating apparatus is not activated.

18. The method of claim 16, further comprising the step of:

storing a substitute address field, and wherein the step of generating each instruction includes substituting the substitute address field in place of an address field in the first template instruction.

19. The method of claim 18, further comprising the step of:

adjusting the stored substitute address field after generating each instruction.

20. The method of claim 18, further comprising the step of:

storing a substitution control signal,

wherein the step of generating each instruction includes substituting the substitute address field in place of an address field in the first template instruction only if the substitution control signal is asserted.

21. The method of claim 16, further comprising the step of:

deactivating the generating apparatus prior to generating the predetermined number of instructions in response to detection that a predetermined condition has been satisfied.

22. A method for generating instructions for controlling a processor, the method comprising the steps of:

storing a first template instruction;

storing a second template instruction;

using a generating apparatus to generate a number of instructions including a first instruction based on the first template instruction and a second instruction based on the second template instruction;

repeatedly using the generating apparatus until a predetermined number of instructions have been generated.

23. The method of claim 22, further comprising:

supplying the generated instructions to the processor when the generating apparatus is activated; and

supplying instructions received from an alternative instruction source to the processor when the generating apparatus is not activated.

24. The method of claim 22, further comprising:

storing a substitute address field, and

wherein the generating apparatus performs the step of substituting the substitute address field in place of an address field in the first template instruction.

25. The method of claim 24, further comprising the step of:

adjusting the stored substitute address field after generating each first instruction.

26. The method of claim 24, further comprising the step of:

storing a first substitution control signal;

wherein the generating apparatus performs the step of substituting the substitute address field in place of an address field in the first template instruction only if the first substitution control signal is asserted.

27. The method of claim 24, wherein:

the generating apparatus performs the step of generating each second instruction by substituting the substitute address field in place of an address field in the second template instruction.

28. The method of claim 27, further comprising the steps of:

adjusting the stored substitute address field after generating each first instruction; and

adjusting the stored substitute address field after generating each second instruction.

29. The method of claim 27, further comprising the steps of:

storing a first substitution control signal; and

storing a second substitution control signal,

wherein the generating apparatus performs the step of substituting the substitute address field in place of an address field in the first template instruction only if the first substitution control signal is asserted, and

wherein the generating apparatus performs the step of substituting the substitute address field in place of an address field in the second template instruction only if the second substitution control signal is asserted.

30. The method of claim 22, further comprising the step of:

deactivating the generating apparatus prior to generating the predetermined number of instructions in response to detection that a predetermined condition has been satisfied.