Source-to-source transformation for language dialects

• US 20070226708A1
• Filed: 03/24/2006
• Published: 09/27/2007
• Est. Priority Date: 03/24/2006
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Varma, Pradeep
• Granted Patent: US 8,015,554 B2
• Time in Patent Office: Days
• US Class Current: 717/139
• CPC Class Codes: G06F 8/51 Source to source

Abstract

An analysis and source-to-source transformation framework covers dialects of programming languages that lack formal definition for all individual dialects. Multiple instantiations of the same compiler front-end tools can be used with different settings to create distinct intermediate forms and maps. Intermediate forms and maps are used in an individual analysis and source-to-source transformation context, and performing the analysis and source-to-source transformation thereupon. A unified tool set is desirably provided, including standard compiler front-end tools and code transformation/generation tools, wherein source code edits are carried out in order to make the source code more amenable to translation to intermediate forms. The analysis results or intermediate forms created by individual tools are used by other tools as well as further analyzed to create a map of the regions of validity and invalidity of the intermediate forms, and tracking the source-code edits performed in order to obtain the same. Among other benefits, this provides a choice of the best tools combination for maximum code analysis coverage.

Claims

1. A computer-assisted method for iteratively interpreting a source code region written in one computer programming language or dialect as another, the method comprising an initial iteration comprising:

generating from said source code region a plurality of different intermediate forms corresponding to different dialect settings; and

generating a map associated with each intermediate form, said map representing regions within the associated intermediate form that are valid.

2. The method as claimed in claim 1, wherein each of the different intermediate forms comprise one or more of text of the source code region, pre-processed text, a lexeme stream, a syntax tree and a typed tree.

3. The method as claimed in claim 1, further comprising generating annotations for valid constructs of at least one intermediate form.

4. The method as claimed in claim 3, wherein the annotations are selected from the group comprising validly analyzed region, valid non-code region, invalid skipped region and, unknown status region.

5. The method as claimed in claim 1, further comprising constructing said map in terms of said source code, or a pre-processed version of said source code.

6. The method as claimed in claim 3, further comprising recording the annotations for valid constructs of the intermediate form in a series of respective layers of the maps associated with the different intermediate forms.

7. The method as claimed in claim 6, wherein there is one annotation layer per intermediate form.

8. The method as claimed in claim 1, further comprising a further iteration comprising:

analyzing the intermediate forms and associated maps generated in a preceding iteration to identify a most suitable intermediate form for said source code region;

transforming the source code region based upon the most suitable intermediate form and associated map;

generating from the transformed source code region a plurality of different intermediate forms corresponding to different dialect settings;

generating a second map associated with each intermediate form, said second map representing regions within the associated intermediate form that are valid; and

recording said transformation and any transformations recorded in the map of said preceding iteration.

9. The method of claim 1, further comprising a final iteration comprising:

analyzing the intermediate forms and associated maps generated in a preceding iteration to identify a most suitable intermediate form for said source code region; and

transforming the source code region based upon the most suitable intermediate form and associated map.

10. The method as claimed in claim 9, wherein said transformation step comprises substituting portions of code within said source code region with replacement portions.

11. A computer program product comprising:

a storage medium readable by a computer system and recording software instructions executable by a computer system for iteratively interpreting a source code region written in one computer programming language or dialect as another by implementing the steps of;

generating from said source code region a plurality of different intermediate forms corresponding to different dialect settings; and

generating a map associated with each intermediate form, said map representing regions within the associated intermediate form that are valid.

12. A computer system comprising:

a processor for executing software instructions;

a memory for storing software instructions;

a system bus coupling the memory and the processor; and

a storage medium recording software instructions that are loadable to the memory for iteratively interpreting a source code region written in one computer programming language or dialect as another by implementing the steps of;

generating from said source code region a plurality of different intermediate forms corresponding to different dialect settings; and

generating a map associated with each intermediate form, said map representing regions within the associated intermediate form that are valid.

13. A computer program product comprising:

a storage medium readable by a computer system and tangibly embodying recording software instructions organized as separate software components executable in combination by a computer system, said software instructions being configured to perform a method for iteratively interpreting a source code region written in one computer programming language or dialect as another, the method comprising an initial iteration comprising the steps of;

generating from said source code region a plurality of different intermediate forms corresponding to different dialect settings; and

generating a map associated with each intermediate form, said map representing regions within the associated intermediate form that are valid.

14. A computer system comprising:

a processor for executing software instructions;

a memory for storing software instructions;

a system bus coupling the memory and the processor; and

a computer program product comprising;

a storage medium readable by a computer system and recording software instructions organized as separate software components executable in combination by a computer system, said software instructions being configured to perform a method for iteratively interpreting a source code region written in one computer programming language or dialect as another, the method comprising an initial iteration comprising;

generating from said source code region a plurality of different intermediate forms corresponding to different dialect settings; and

generating a map associated with each intermediate form, said map representing regions within the associated intermediate form that are valid.

15. A computer-assisted method for iteratively interpreting a source code region written in one computer programming language or dialect as another, the method comprising an initial iteration comprising:

generating from said source code region a plurality of different intermediate forms corresponding to different dialect settings;

generating a map associated with each intermediate form, said map representing regions within the associated intermediate form that are valid;

analyzing the intermediate forms and associated maps to identify a most suitable intermediate form for said source code region; and

transforming the source code region based upon the most suitable intermediate form and associated map.