Source-to-source transformation for language dialects

• US 8,015,554 B2
• Filed: 03/24/2006
• Issued: 09/06/2011
• Est. Priority Date: 03/24/2006
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Varma, Pradeep
• Primary Examiner(s): Yigdall; Michael J
• Assistant Examiner(s): HAYIM, SAMUEL E
• Application Number:
  US11/388,353
• Publication Number:
  US 20070226708A1
• Time in Patent Office: 1,992 Days
• Field of Search: None
• US Class Current: 717/137
• 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 single source code region written in one computer programming language as another computer programming language, the method comprising an initial iteration comprising:

generating, by a computing device, from said single source code region a plurality of different intermediate forms each corresponding to a different computer programming language, said generating said plurality of different intermediate forms comprising;

pre-processing said source code region to create a textual elaborated output;

lexing said textual elaborated output from said preprocessing to create a lexeme stream output;

parsing said lexeme stream output from said lexing to create an abstract syntax tree output; and

type checking said abstract syntax tree output from said parsing to create a typed tree output; and

generating, by said computing device, a multilayered map associated with each of said plurality of different intermediate forms and each map corresponding to said different computer programming language, said multilayered map representing a sequence of pre-processed code ranges that together cover the entirety of said textual elaborated output with at least one notation per layer of said multilayer map designating;

a validly analyzed region;

a valid non-code region;

an invalid skipped region; and

an unknown status region.

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

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

transforming, by said computing device, the source code region based upon the most suitable intermediate form and associated map;

generating, by said computing device, from the transformed source code region a plurality of different intermediate forms corresponding to different compiler flag settings;

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

recording, by said computing device, said transformation and any transformations recorded in the map of said preceding iteration.

3. 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.

4. The method as claimed in claim 3, wherein said transformation step comprises:

substituting portions of code within said source code region with replacement portions.

5. A computer storage medium readable by a computer tangibly embodying a program of instructions executable by said computer for performing a method for iteratively interpreting a single source code region written in one computer programming language as another computer programming language, the method comprising an initial iteration comprising:

generating from said single source code region a plurality of different intermediate forms each corresponding to a different computer programming language; and

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

6. The method as claimed in claim 5, further comprising a further iteration comprising:

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

transforming, by said computing device, the source code region based upon the most suitable intermediate form and associated map;

generating, by said computing device, from the transformed source code region a plurality of different intermediate forms corresponding to different compiler flag settings;

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

recording, by said computing device, said transformation and any transformations recorded in the map of said preceding iteration.

7. 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 single source code region written in one computer programming language or as another computer programming language by implementing an initial iteration comprising;

generating from said single source code region a plurality of different intermediate forms each corresponding to a different computer programming language; and

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

8. The method as claimed in claim 7, further comprising a further iteration comprising:

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

transforming, by said computing device, the source code region based upon the most suitable intermediate form and associated map;

generating, by said computing device, from the transformed source code region a plurality of different intermediate forms corresponding to different compiler flag settings;

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

recording, by said computing device, said transformation and any transformations recorded in the map of said preceding iteration.

9. 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 single source code region written in one computer programming language as another computer programming language, the method comprising an initial iteration comprising;

generating from said single source code region a plurality of different intermediate forms each corresponding to a different computer programming language; and

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

10. The method as claimed in claim 9, further comprising a further iteration comprising:

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

transforming, by said computing device, the source code region based upon the most suitable intermediate form and associated map;

generating, by said computing device, from the transformed source code region a plurality of different intermediate forms corresponding to different compiler flag settings;

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

recording, by said computing device, said transformation and any transformations recorded in the map of said preceding iteration.

11. 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 single source code region written in one computer programming language as another computer programming language, the method comprising an initial iteration comprising;

generating from said single source code region a plurality of different intermediate forms each corresponding to a different computer programming language; and

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

12. The method as claimed in claim 11, further comprising a further iteration comprising:

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

transforming, by said computing device, the source code region based upon the most suitable intermediate form and associated map;

generating, by said computing device, from the transformed source code region a plurality of different intermediate forms corresponding to different compiler flag settings;

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

recording, by said computing device, said transformation and any transformations recorded in the map of said preceding iteration.

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

generating from said single source code region a plurality of different intermediate forms each corresponding to a different computer programming language;

generating a map associated with each of said plurality of different intermediate forms, 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.

14. The method as claimed in claim 13, further comprising a further iteration comprising:

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

transforming, by said computing device, the source code region based upon the most suitable intermediate form and associated map;

generating, by said computing device, from the transformed source code region a plurality of different intermediate forms corresponding to different compiler flag settings;

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

recording, by said computing device, said transformation and any transformations recorded in the map of said preceding iteration.