Stack unique signatures for program procedures and methods

• US 20030154464A1
• Filed: 01/16/2002
• Published: 08/14/2003
• Est. Priority Date: 01/16/2002
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Wynn, Allen Chester, Ullmann, Lorin
• Granted Patent: US 7,080,359 B2
• Time in Patent Office: Days
• US Class Current: 717/130
• CPC Class Codes: G06F 2209/481 Exception handling
• CPC Class Codes: G06F 9/4484 Executing subprograms
• CPC Class Codes: G06F 9/4486 Formation of subprogram jump address

Abstract

A system and method for inserting stack signature marking segments into application program modules at the entry and exit points of the application program segments prior to compilations. Unique module identifier values are assigned to each application program module. During execution of the modified application software modules, upon entry into a new module or instance of a module, the unique module identifier is pushed onto the stack along with an instance number and an entry indicator. Upon termination of the module or instance of a module, the unique module identifier is pushed onto the stack with the instance number and an exit indicator, thereby placing an entry signature and an exit signature onto the stack bracketing the stack frame assigned to that module or module instance. During debug of exceptions, these signatures may be used to locate and identify stack frames and their associated software modules.

Claims

1. A method for marking a processing stack with signatures to indicate which portions of the stack were utilized by which software code modules, said method comprising the step of:

assigning unique module identifier values to a plurality of code modules; and

upon execution of said code modules, pushing onto a processing stack said unique module identifiers within stack frames allocated to said code modules.

2. The method as set forth in claim 1 further comprising the steps of:

generating an instance number for each instantiation of a code module; and

pushing onto said processing stack said instance numbers associated with said unique module identifier values.

3. The method as set forth in claim 1 further comprising the step of pushing onto said stack an entry/exit indicator associated with said unique module identifier.

4. The method as set forth in claim 1 further comprising the step of inserting stack signature marking software segments into application source code, said insertion step being performed prior to compilation of said application source code.

5. The method as set forth in claim 4 further comprising the step of providing a global control which indicates all application source code modules are to have stack signature marking software segments inserted into them during a given compilation job.

6. The method as set forth in claim 4 further comprising the step of providing a selective control which indicates only certain application source code modules are to have stack signature marking software segments inserted into them during a given compilation job.

7. A computer readable medium encoded with software for marking a processing stack with signatures to indicate which portions of the stack were utilized by which application code modules, said software causing a processor to perform the steps of:

assigning unique module identifier values to a plurality of code modules; and

upon execution of said code modules, pushing onto a processing stack said unique module identifiers within stack frames allocated to said code modules.

8. The computer readable medium as set forth in claim 7 further comprising software to perform the steps of:

generating an instance number for each instantiation of a code module; and

pushing onto said processing stack said instance numbers associated with said unique module identifier values.

9. The computer readable medium as set forth in claim 7 further comprising software for performing the step of pushing onto said stack an entry/exit indicator associated with said unique module identifier.

10. The computer readable medium as set forth in claim 7 further comprising software for performing the step of inserting stack signature marking software segments into application source code, said insertion step being performed prior to compilation of said application source code.

11. The computer readable medium as set forth in claim 10 further comprising software for performing the step of providing a global control which indicates all application source code modules are to have stack signature marking software segments inserted into them during a given compilation job.

12. The computer readable medium as set forth in claim 10 further comprising software for performing the step of providing a selective control which indicates only certain application source code modules are to have stack signature marking software segments inserted into them during a given compilation job.

13. A system for inserting stack signature marking code segments into application software modules prior to compilation, said system cooperating with a compiler and comprising:

a control means operable by a user to indicate whether or not to insert stack signature marking code segments into application software modules; and

a code insertion means which, responsive to the operation of the control means, searches for entry points and exits points in application software modules and inserts stack signature marking code segments following each entry point and prior to each exit point into said application software modules.

14. The system of claim 14 wherein said control means comprises a global control means for indicating insertion of stack signature marking code segments are to be inserted into all application software modules to be compiled.

15. The system of claim 15 wherein said control means comprises a selective control means for indicating specific applications software modules or groups of application software modules into which stack signature marking code segments are to be inserted.