WinFPT and ftp - Fortran Engineering

top_left_banner SimCon logo

fpt - Tools for Fortran Engineering - What Would You like to do to Your Code?

What would you like to do to your code?

The following facilities are currently supported in WinFPT and fpt. Follow the hyperlinks from the headings for more information. Some of the links will take you directly to the fpt reference manual.

And if you can't find what you want, please contact SimCon and we will try to help.

Error Checking

Most large programs contain errors. Sometimes they result in unexplained crashes. More often the program runs, but the results are slightly inaccurate. Inaccuracies of about 5% are quite common because they are too small to be recognised by the program authors.

Some classes of error are systematic in Fortran programs. These classes, and the fpt facilities to trap them, are described here.

The errors listed below are rarely found by Fortran compiler and linkers. fpt can show that a code is free from them.

Dead Code	Unused sub-programs - Find subroutines and functions which are never called Un-reachable Code - Find statements which can never be executed
Dead Variables	Variables used but never assigned - Check across all shared memory Variables assigned but never used Variables declared but never accessed
Mis-matched Arguments	Wrong Data Type - find, e.g. integers passed to routines where reals were expected Wrong data size - find, e.g. real(kind=4) objects passed where real(kind=8) objects were expected Wrong intent - find, e.g. variables with INTENT(IN) which are written to Wrong protocol - find, e.g. variables passed by value which should be passed by reference Wrong array bounds - find inconsistencies between the bounds of the arrays passed and expected Missing arguments - detect missing arguments which are not declared to be optional
Mis-aligned Memory	Mis-aligned COMMON blocks - Show variables with different addresses in different routines COMMON blocks with inconsistent lengths - Find named COMMON blocks with different lengths in different routines Mixed Equivalence - Find variables of different data types occupying the same memory
Errors in Expressions	Loss of Precision - Detect mixed precision in arithmetic expressions Accidental whole array assignments - Find missing sub-scripts in DO loops - the whole array is assigned Integers rased to negative powers - Find errors like Time_secs=Time_microsec10*(-6) (This won't work!)
Errors in Names	Parameters with different values in different routines - Find, e.g. g=32.2 and g=9.81 in the same program! Variables with different attributes in different routines Variables with the same names as keywords or intrinsics
Errors in Physical Units and Dimensions	Variables forced to be dimensionless Volumes added to areas, volts added to amps

Measurement and Assessment

Code metrics allow you to assess the scale of an engineering task, and the risks and cost of ownership of a software package. They are key to successful project management.

Code Metrics	How big is it? - Count the number of lines, statements, comments, blank lines How complex? - Measure the cyclomatic complexity How maintainable? - Assess the meaningfulness and uniqueness of variable names and the level of commentary
Report Generation	File list and INCLUDE tree Sub-program list and Module Use tree Call Tree Symbol Table - shown collated across all routines and optionally filtered by attributes Program and Sub-program Interfaces - list both arguments and shared memory interfaces COMMON Block listings - listed in address order, collated across routines

Structural Engineering

With fpt, you can systematically clean up codes, enforce declarations, insert IMPLICIT NONE statements and move COMMON blocks to INCLUDE files. The variable name editing facilities make it easy to apply naming conventions. With these tools you can significantly reduce the workload and risk of future maintenance.

Declarations & Names	Add Declarations - declaring all undeclared variables Add IMPLICIT NONE - enforcing IMPLICIT NONE, removing existing IMPLICIT statements Specify global SAVE - removing local SAVE statements Change kinds and data sizes - adding or changing existing declarations Rename Variables - selecting only the complete variable names and ignoring keywords Edit Variable Names - applying editing rules only to the variable names
COMMON Blocks	Move COMMON blocks to include files - using a single file or one file for each COMMON Move all Static Variables to COMMON - building a data dictionary
Control Constructs	Remove labels from Executable Statements - moving the labels to CONTINUE statements Replace IF (...) Statement by IF-THEN Replace SELECT CASE - rewriting the code as an IF - THEN - ELSE chain
Interactive Controller	Build an Interactive Control Environment - automatically adding code to inspect and change variables and to start and stop execution
Correct Errors	Correct Inconsistent Arguments - re-writing the arguments or add type conversions Correct Formats - add missing commas and delimiters

Software Migration

fpt converts the control and data structures found in legacy systems to modern Fortran. Many old codes are hugely valuable. With fpt you can keep them and maintain them. Our approach to migration is described here. Also, please see the notes on migration in the reference manual.

VMS Migration	Insert translation routines for VMS file formats - using Sector7's VMS file handling API. Re-code ISAM File I/O - replacing the I/O statements by sub-program calls Set up the arguments for Sector7's VMS emulation libraries - filling in missing arguments and inserting additional arguments as needed.
Gould-SEL Migration	Replace GOULD-SEL DATAPOOL - by a standard COMMON block Replace Gould-SEL Memory Management - e.g. EXTENDED DUMMY, EXTENDED GLOBAL etc. Replace ENCODE and DECODE - using internal READ and WRITE
Arguments and Sub-programs	Supply Missing Arguments Expand Internal Routines In-line - handle both Gould-SEL and Fortran 90 formats
Code Formatting	Convert Tab format to Free or Fixed Format Control Number of Continuation Lines - split up long statements or squeeze them to fit Convert HEX or Octal Number Formats

Run-time Testing

The coverage analysis allows you to see how much of a code is actually exercised by your test suite. The trace and record/replay facilities allow you to isolate components of a code for reproducible tests, to compare runs on the new and old systems in migration, and to investigate the conditions which lead to a program crash.

Coverage Analysis	Instrumenting Code - to record all sections of the code visited in a test
Trace Data Flow	Capture I/O and Sub-program Interfaces - capture data at interfaces to replay test runs without the original inputs Capture flow and all scalar assignments - trace data and program flow to replay or check data flow in program migration or debugging

Optimisation

With fpt you can write and maintain your code using small data access routines to encapsulate data structures, and then expand the routines in-line to achieve efficiency in production builds.

Optimisation for Speed of Execution

Expand Routines In-line
Unroll DO Loops

Formatting and Pretty-printing

fpt contains a powerful and flexible code formatter and browser. You can switch safely and easily from FORTRAN 77 fixed format to Fortran 90 free format - and back again if you need to test on an old compiler.

Layout Conversion	Convert Layout - between fixed format, VMS tab format and Fortran 90 free format.
Pretty Printing	Indentation - Indent for control constructs and declarations Spacing - Specify spacing for symbols, numbers, labels and separately for every keyword and operator Upper/lower case - Specify case separately for keywords, operators, symbols, intrinsics Number format - Add leading and trailing zeros, specify data size and kind Renumbering labels - Number labels systematically in ascending order
Code Browsing	Full syntax colouring - The colours are syntax sensitive - a keyword used as a variable is coloured as a variable View by sub-program or by file - in sub-program view INCLUDE files appear in-line Flexible navigation - Navigate using the file list, call tree, symbol table or error table

Security - Obfuscation

Have you ever needed to send a code to a compiler vendor to analyse a problem, without giving them access to secret material? Have you ever needed to release code to be built by a third party without releasing sensitive information? With fpt, you can do this.

Make Code Unreadable

Scramble Names and Strip Comments - make sensitive code safe to pass to third parties