INTERPRETING FUNCTIONS UTILIZING A HYBRID OF VIRTUAL AND NATIVE MACHINE INSTRUCTIONS

• US 20020046298A1
• Filed: 06/30/1997
• Published: 04/18/2002
• Est. Priority Date: 06/30/1997
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: BAK, LARS, GRIESEMER, ROBERT
• Granted Patent: US 6,513,156 B2
• Time in Patent Office: Days
• US Class Current: 719/310
• CPC Class Codes: G06F 9/30174 for non-native instruction set, e.g. Javabyte, legacy code
• CPC Class Codes: G06F 9/45516 Runtime code conversion or optimisation

Abstract

Systems and methods for increasing the execution speed of virtual machine instructions for a function are provided. A portion of the virtual machine instructions of the function are compiled into native machine instructions so that the function includes both virtual and native machine instructions. Execution of the native machine instructions may be accomplished by overwriting a virtual machine instruction of the function with a virtual machine instruction that specifies execution of the native machine instructions. Additionally, the original virtual machine instruction may be stored so that the original virtual machine instructions can be regenerated.

Claims

1. In a computer system, a method for increasing the execution speed of virtual machine instructions, the method comprising:

inputting virtual machine instructions for a function; and

compiling a portion of the function into at least one native machine instruction so that the function includes both virtual and native machine instructions.

2. The method of claim 1, further comprising overwriting a selected virtual machine instruction of the function with a new virtual machine instruction, the new virtual machine instruction specifying execution of the at least one native machine instruction.

3. The method of claim 2, wherein the new virtual machine instruction includes a pointer to the at least one native machine instruction.

4. The method of claim 2, further comprising storing the selected virtual machine instruction before it is overwritten.

5. The method of claim 2, further comprising storing, a back pointer to a location of the new virtual machine instruction.

6. The method of claim 2, wherein the new virtual machine instruction includes a pointer to a data block in which is stored the at least one native machine instruction, a copy of the selected virtual machine instruction, and a back pointer to a location of the new virtual machine instruction.

7. The method of claim 6, further comprising generating the virtual machine instructions that were input by storing the copy of the selected virtual machine instruction stored in the data block at the location specified by the back pointer.

8. The method of claim 1, further comprising determining which portion of the function to compile into the at least one native machine instruction.

9. The method of claim 8, wherein determining which portion of the function to compile includes analyzing statistics on the execution speed of the virtual machine instructions of the function.

10. The method of claim 1, wherein the virtual machine instructions are Java virtual machine instructions.

11. A computer program product that increases the execution speed of virtual machine instructions, comprising:

computer code that receives as input virtual machine instructions for a function;

computer code that compiles a portion of the function into at least one native machine instruction so that the function includes both virtual and native machine instructions; and

a computer readable medium that stores the computer codes.

12. The computer program product of claim 11, wherein the computer readable medium is selected from the group consisting of CD-ROM, floppy disk, tape, flash memory, system memory, hard drive, and data signal embodied in a carrier wave.

13. The computer program product of claim 11, further comprising computer code that overwrites a selected virtual machine instruction of the function with a new virtual machine instruction, the new virtual machine instruction specifying execution of the at least one native machine instruction.

14. The computer program product of claim 13, wherein the new virtual machine instruction includes a pointer to the at least one native machine instruction.

15. The computer program product of claim 13, further comprising computer code that stores the selected virtual machine instruction before it is overwritten.

16. The computer program product of claim 13, further comprising computer code that stores a back pointer to a location of the new virtual machine instruction.

17. The computer program product of claim 13, wherein the new virtual machine instruction includes a pointer to a data block in which is stored the at least one native machine instruction, a copy of the selected virtual machine instruction, and a back pointer to a location of the new virtual machine instruction.

18. The computer program product of claim 17, further comprising computer code that generates the virtual machine instructions that were input by storing copy of the selected virtual machine instruction stored in the data block at the location specified by the back pointer.

19. The computer program product of claim 11, further comprising computer code that determines which portion of the function to compile into the at least one native machine instruction.

20. The computer program product of claim 19, wherein the computer code that determines which portion of the function to compile includes computer code that analyzes statistics on the execution speed of the virtual machine instructions of the function.

21. The computer program product of claim 11, wherein the virtual machine instructions are Java virtual machine instructions.

22. A computer system for executing virtual machine instructions, comprising:

a processor;

a memory coupled to the processor that stores virtual machine instructions for a function; and

an interpreter operating on the processor that executes the function by compiling a portion of the function into at least one native machine instruction so that execution of the function includes execution of both virtual and native machine instructions.

23. The system of claim 22, wherein the interpreter overwrites a selected virtual machine instruction of the function with a new virtual machine instruction, the new virtual machine instruction specifying execution of the at least one native machine instruction.

24. The system of claim 23, wherein the new virtual machine instruction includes a pointer to the at least one native machine instruction.

25. The system of claim 23, wherein the interpreter stores the selected virtual machine instruction before it is overwritten.

26. The system of claim 23, wherein the interpreter stores a back pointer to a location of the new virtual machine instruction.

27. The system of claim 23, wherein the new virtual machine instruction includes a pointer to a data block in which is stored the at least one native machine instruction, a copy of the selected virtual machine instruction, and a back pointer to a location of the new virtual machine instruction.

28. The system of claim 27, wherein the interpreter generates the virtual machine instructions that were input by storing the copy of the selected virtual machine instruction stored in the data block at the location specified by the back pointer.

29. The system of claim 22, wherein the interpreter determines which portion of the function to compile into the at least one native machine instruction.

30. The system of claim 29, wherein the interpreter analyzes statistics on the execution speed of the virtual machine instructions of the function to determine which portion of the function to compile into the at least one native machine instruction.

31. The system of claim 22, wherein the virtual machine instructions are Java virtual machine instructions.

32. In a computer system, a method for increasing the execution speed of Java virtual machine instructions, the method comprising:

inputting Java virtual machine instructions for a function;

compiling a portion of the function into at least one native machine instruction;

storing a copy of a selected virtual machine instruction at a beginning of the portion of the function;

storing a back pointer to a location of the selected virtual machine instruction; and

overwriting the selected virtual machine instruction with a new virtual machine instruction, the new virtual machine instruction specifying execution of the at least one native machine instruction so that the function includes both virtual and native machine instructions.

33. The method of claim 32, wherein the new virtual machine instruction includes a pointer to the at least one native machine instruction.

34. The method of claim 32, wherein the new virtual machine instruction includes a pointer to a data block in which is stored the at least one native machine instruction, the copy of the selected virtual machine instruction, and the back pointer.

35. The method of claim 32, further comprising generating the virtual machine instructions that were input by storing the copy of the selected virtual machine instruction stored in the data block at the location specified by the back pointer.

36. The method of claim 32, further comprising determining which portion of the function to compile into the at least one native machine instruction.

37. The method of claim 36, wherein determining which portion of the function to compile includes analyzing statistics on the execution speed of the virtual machine instructions of the function.

39. The computer program product of claim 38, wherein the computer readable medium is selected from the group consisting of CD-ROM, floppy disk, tape, flash memory, system memory, hard drive, and data signal embodied in a carrier wave.

40. The computer program product of claim 38, wherein the new virtual machine instruction includes a pointer to the at least one native machine instruction.

41. The computer program product of claim 38, wherein the new virtual machine instruction includes a pointer to a data block in which is stored the at least one native machine instruction, the copy of the selected virtual machine instruction, and the back pointer.

42. The computer program product of claim 38, further comprising computer code that generates the virtual machine instructions that were input by storing the copy of the selected virtual machine instruction stored in the data block at the location specified by the back pointer.

43. The computer program product of claim 38, further comprising computer code that determines which portion of the function to compile into the at least one native machine instruction.

44. The computer program product of claim 43, wherein the computer code that determines which portion of the function to compile includes computer code that analyzes statistics on the execution speed of the virtual machine instructions of the function.

46. The system of claim 45, wherein the new virtual machine instruction includes a pointer to the at least one native machine instruction.

47. The system of claim 45, wherein the new virtual machine instruction includes a pointer to a data block in which is stored the at least one native machine instruction, the copy of the selected virtual machine instruction, and the back pointer.

48. The system of claim 45, wherein the interpreter generates the virtual machine instructions that were input by storing the copy of the selected virtual machine instruction stored in the data block at the location specified by the back pointer.

49. The system of claim 45, wherein the interpreter determines which portion of the function to compile into the at least one native machine instruction.

50. The method of claim 49, wherein the interpreter analyzes statistics on the execution speed of the virtual machine instructions of the function to determine which portion of the function to compile into the at least one native machine instruction.

38. A computer program product that increases the execution speed of virtual machine instructions, comprising:

computer code that receives as input virtual machine instructions for a function;

computer code that compiles a portion of the function into at least one native machine instruction;

computer code that stores a copy of a selected virtual machine instruction at a beginning of the portion of the function;

computer code that stores a back pointer to a location of the selected virtual machine instruction;

computer code that overwrites the selected virtual machine instruction with a new virtual machine instruction, the new virtual machine instruction specifying execution of the at least one native machine instruction so that the function includes both virtual and native machine instructions; and

a computer readable medium that stores the computer codes.

45. A computer system for executing virtual machine instructions, comprising:

a processor;

a memory coupled to the processor that stores virtual machine instructions for a function; and

an interpreter operating on the processor to execute the function by compiling a portion of the function into at least one native machine instruction, storing a copy of a selected virtual machine instruction at a beginning of the portion of the function, storing a back pointer to a location of the selected virtual machine instruction, and overwriting the selected virtual machine instruction with a new virtual machine instruction, the new virtual machine instruction specifying execution of the at least one native machine instruction so that the function includes both virtual and native machine instructions.

51. A method of generating hybrid virtual and native machine instructions, comprising:

inputting a sequence of virtual machine instructions for a function;

selecting a virtual machine instruction of the sequence of virtual machine instructions; and

overwriting the selected virtual machine instruction with a new virtual machine instruction that specifies at least one native machine instruction.

52. The method of claim 51, wherein the new virtual machine instruction includes a pointer to the at least one native machine instruction.

53. The method of claim 51, further comprising storing in a data block the at least one native machine instruction.

54. The method of claim 53, further comprising storing in the data block a copy of the selected virtual machine instruction that was overwritten in the sequence of virtual machine instructions by the new virtual machine instruction.

55. The method of claim 53, further comprising storing in the data block a pointer to a location of the new virtual machine instruction in the sequence of virtual machine instructions.

56. The method of claim 53, further comprising storing the data block in an array of blocks.

57. The method of claim 51, further comprising compiling a portion of the sequence of virtual machine instructions beginning with the selected virtual machine instruction into the at least one native machine instructions.

58. The method of claim 51, wherein the virtual machine instructions are Java virtual machine instructions.

60. The stored data structure of claim 59, wherein the new virtual machine instruction includes a pointer to the at least one native machine instruction.

61. The stored data structure of claim 59, wherein the it least one native machine instruction is stored in a data block.

62. The stored data structure of claim 61, wherein the data block stores a copy of the selected virtual machine instruction that was overwritten in the sequence of virtual machine instructions by the new virtual machine instruction.

63. The stored data structure of claim 61, wherein the block stores a pointer to a location of the new virtual machine instruction in the sequence of virtual machine instructions.

64. The stored data structure of claim 61, wherein the data block is stored in an array of blocks.

65. The stored data structure of claim 59, wherein the at least one native machine instruction is generated from a compilation of a portion of the sequence of virtual machine instructions beginning with the selected virtual machine instruction.

66. The stored data structure of claim 59, wherein the virtual machine instructions are Java virtual machine instructions.

59. A stored data structure of hybrid virtual and native machine instructions, comprising:

a sequence of virtual machine instructions for a function including a new virtual machine instruction;

at least one native machine instruction specified by the new virtual machine instruction for execution with the sequence of virtual machine instructions; and

a computer readable medium that stores the sequence of virtual machine instructions and the at least one native machine instruction.