Un-Used Variables Part 5 1/4 - VarDumpah

[Mike Trader]

Thx Borje

FYI there is a utility called DrawFunk that does some interesting
things at: http://www.kgpsoftware.com/
in the Products section. Not sure whos site that is, but thx!
No source code tho

Also check out: http://www.collakesoftware.com/
under downloads at the bottom of the page
ASMVARS v1.01


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Kind Regards
Mike

[This message has been edited by Mike Trader (edited July 31, 2001).]

[Borje Hagsten]

Glad to hear it finally works, Charles. Means I now can fire my lazy
brain and live happily ever after..

Just uploaded yet another fix. Excluded declarations of Subs/Functions
from usage calculation, since otherwise, Declare + actual Sub/Function
was considered as one use. This change, in DoProcess - ExtractLine,
right before "GOSUB ChkVariables" (line 519 in new code)

Previous changes, hm. In DoProcess - ExtractLocals, removed IF/THEN clause
with ARRAY SCAN gVars (somewhere around line 694). Also changed
"IF isGLOBAL = 1 THEN" to "IF isGLOBAL < 2 THEN" (line 694 in new code)
and added "Vars(iVars).iType = isGlobal" (line 702 in new code)

Then, added "IF igVars AND ilVars THEN" block to beginning of DoSaveResults.
Compare latest code with your version, side by side, to find the changes.

Most recent upload is new file, where I also did some minor cosmetic changes
to report, in DoSaveResults (like added decl. line numbers to total ref. count).


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[Mike Trader]

I found a few more multi - legged features in my app today. I have
posted the latest ver 4.0 of VarDumpah in the Source code forum.


Borje,

Can you tell me where you made changes, cos ive changed a few things
in your excellent proggy to my liking and I would like to just
drop in the new stuff.

If you could just tell me Line xxx to Line xxx is new that would
be great



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Kind Regards
Mike

[Charles Dietz]

Perfect!

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[Borje Hagsten]

See, I told you my mind is on vacation.. Thanks a lot, just uploaded
fixed file. Second part there, on AllLocals, was okay though.


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[Charles Dietz]

Borje, It fixed the simple example, but not my real application.
I took a look at your code, and it looks to me like there is a mistake on
line # 841.

You have: ARRAY DELETE lVars(cTmp - 1)
should be: ARRAY DELETE lVars(I)

Line #847 may be the same error.


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[Borje Hagsten]

Of course it couldn't work, because I'm an idiot. Not easy when your
mind is on vacation. Previous fix: 1, collect local vars, 2, compare
local's array against global's array. 3, collect global vars.

Can you see the error? Nothing to compare with in step 2. Sigh! Ok,
now it stores the type of declare for local DIM and do the compare
against global's array just before report. Tested on your situation
Charles and it seems to handle it properly.

Fixed file uploaded to http://www.tolken99.com/pb/pbcodec.zip

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[Charles Dietz]

Borje, I just downloaded your latest, and my problem still exists in pbcodec.
Here is a simple example illustrating the probem:
pbcodec reports that myArray is an unused local variable.

'main file: "problem.bas" -------------------

#COMPILE EXE
#INCLUDE "Problem.inc"

FUNCTION PBMAIN
   initialize
   myArray(1) = "Try this string"
   MSGBOX "Done"
END FUNCTION

SUB initialize
   DIM myArray(100)
END SUB


'include file: "problem.inc ------------------
GLOBAL myArray() AS STRING
DECLARE SUB initialize

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[This message has been edited by Charles Dietz (edited July 30, 2001).]

[Lance Edmonds]

Foremostly, DIM simply declares a variable.

If the DIM statement does not specify scope (with an "AS LOCAL/STATIC/GLOBAL" clause) and the variable is already declared GLOBAL within the code, PowerBASIC simply uses that variable (hence the variable in that Sub/Function will use the GLOBAL variable of the same name).

To explicitly define the scope of a variable, you should use the LOCAL or STATIC statements, or DIM..AS LOCAL/STATIC/GLOBAL.

Clear as mud?

------------------
Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Borje Hagsten]

Thanks Mike, fixed and uploaded. Well, I'll try to answer: Using labels and
GOTO or GOSUB inside a Function or Sub is *much* faster. GOTO is fastest,
but I like GOSUB because RETURN makes life so easy. Personally, I also think
it's easier to follow flow when labels have been used inside same routine,
instead of external calls, but that's me - I know many disagree with me there..

DIM vs LOCAL is sometimes a mystery to me too. LOCAL allocates memory on the
stack and can take advantage of "automatically" becoming register variables,
if there are any registers available and REGISTER NONE *not* have been used.

If using LOCAL, it can differ a lot if most used variables are declared first,
since the chance of ending up as register variable is higher. Can of course be
over-ridden by stating #REGISTER NONE and then use: REGISTER var AS LONG..

DIM probably uses the global heap (?), which makes it a bit more flexible,
but documentation states they both are strictly local, which is true, until
DIM is used to redim a global variable. Sometimes, the compiler is to kind
to us, I think. One should have to use REDIM on global vars, because in a
huge project, it can be easy to forgot that what you think is DIM'd as a
local var/array, in fact becomes a REDIM'd global one. No big deal and
to late to change, but DIM, IMHO, can be source for confusion, so I prefer
using LOCAL and GLOBAL when I can.

Like Tom has pointed out several times, it's wise to use a prefix in name,
like g_var for globals vars, etc, but for many of us, that means to change
old habits. I have tried, but always fall back on stupid "blind" naming.
You obviously can't teach old dogs like me to sit..


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[Mike Trader]

Borje,
tiny bug ...

     CASE %WM_TIMER
         KILLTIMER  CBHNDL, 1
         CALL DoInitProcess(CBHNDL, Files(1))

should be

     CASE %WM_TIMER
         KILLTIMER  CBHNDL, 1
         CALL DoInitProcess(CBHNDL, Files(0))

Great app!

any chance of a quick answer to my questions above

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Kind Regards
Mike

[Borje Hagsten]

Okay, think I have it fixed now - new file uploaded. Had to check DIM
more carefully, since DIM/REDIM may have been preceeded with a GLOBAL
declare of same variable. Seems to work now..

Just remember one thing - this whole project is result of many people's
work, all originating from question from Mike, code by Scott Slater and
extensive help and tips from a bunch of helpful souls, where Lance of
course has an honorary chair. I am just one of the piano players here.
Once again, the powerful PB community has spoken..


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[Mike Trader]

I have included better array handling and fixed a few bugs in VarDumpah.
The latest version is in the Source Code Forum.

If you use it to find and delete unused variables in its own code
this is a good test due to all the words like GLOBAL LOCAL etc used in it.

You can drag and drop multiple files at once. It processed 11 files
(and the 11 includes in each file) in the project that prompted
this program development.

I love Borje and Lances work, your code is more sophisticated
than mine but I have about 100 unused variables in 11 apps.
I dont want to take the time to go thru each one deleting all them.

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Kind Regards
Mike

[This message has been edited by Mike Trader (edited July 29, 2001).]

[Charles Dietz]

borje,

from my vantage point, your program is behaving perfectly with one exception.
i keep downloading your latest, hoping that you have changed this one problem.

in my code, i declare all of my global arrays in an include file.
i then dimension them in a sub of the main file as shown below:

'include file -----------
global myarray as string

'main file --------------
sub initialize()
dim myarray(100)

i should point out that myarray() is not referenced again in sub initialize,
but is used many, many times in other subs.

your program reports myarray as an unused local variable. but the compiler
treats it as global, not local. in fact, if the dim is changed to redim,
your program reports correctly. i don't believe redim should treat a
variable's scope any different than the dim statement. once, a variable
is declared as a global, then unless it is explicitly declared local in a sub,
it must be treated as a global variable.

ref lance's responce july 25: http://www.powerbasic.com/support/pb...ead.php?t=4092

borje, that syntax is allowed. the "as global" portion is currently optional,
but recommended for clarity (to avoid scope confusion).

if you have problems when omitting the "as global" clause, there must be some
other issue in the code affecting the scope of the variable/array.

i believe borje, that your pbcodec program is destined to become nearly as
popular as your remarkable poffs program, so please keep perfecting it.


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[Mike Trader]

Borje,

I have been studying your code. I have learnt alot form this whole
execise about how you pros write. If I knew the language better I
think i would have cover more in VarDumpah.

I have a couple of questions ..
why do write like this:

FUNCTION DoProcess(BYVAL TheFile AS STRING, BYVAL fNum AS LONG, WhatRun AS LONG) AS LONG
'
' GOSUB ExtractLine
'
EXIT FUNCTION

'---------------------------------------------------------
' Extract line from main text
'---------------------------------------------------------
ExtractLine:
'
'
RETURN

Why Not just declare the Sub:
FUNCTION DoProcess(BYVAL TheFile AS STRING, BYVAL fNum AS LONG, WhatRun AS LONG) AS LONG
'
' GOSUB ExtractLine
'
EXIT FUNCTION

'---------------------------------------------------------
' Extract line from main text
'---------------------------------------------------------
SUB ExtractLine
'
'
RETURN

I assume this is slower??
Is it that much slower?

Also in general, why do some people use DIM over LOCAL?
Ive never been clear on the practical difference in use

LOCAL ci AS LONG, p AS LONG, Letter AS BYTE PTR ' etc
vs.
DIM ci AS LONG, p AS LONG, Letter AS BYTE PTR ' etc

also, why cant you declare GLOBAL arrays the same way you can
LOCAL arrays?
ie:

GLOBAL tmpFiles(4) AS STRING
vs.
FUNCTION DoGetIncFiles(BYVAL TheFile AS STRING) AS LONG
'
REDIM tmpFiles(4) AS STRING

I am realizing that I have to check any array DIM or REDIM statements
against the GLOBAL declarations of arrays in case the DIM is just
dimensioning a GLOBAL array rather than declaring and dimensioning
a LOCAL array.

I got a little writing to do...


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Kind Regards
Mike

[Borje Hagsten]

Okay, I see the problem and have just uploaded a fix. Now it looks for
" LIB " when "DECLARE " flag has been set and excludes such declarations.

Also, in DoProcess, under label ExtractLine, I added code to scan line
with colons and replace those inside paranthesis with something else.
Seems to work fine. Also changed from deleting text within double quotes
to simply blank it out. Same result, but should be a bit faster.

Still a lot left to do with it, like what you pointed out - parsing for
multiple include dirs, etc, but it'll get there some day..


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[Lance Edmonds]

Borje, you code is simply excellent, no question! I think I'll abandon my pursuit of the original CheckIt.Bas now!

However, your code too has a couple of problems.

For example, I have a statement: GLOBAL gprinters() AS STRING and in PBMAIN i have a statement DIM gprinters(1:1) AS GLOBAL STRING. Your parsing engine says I have a variable that is both local and global. Also, the reference count is shown as -1.

If I change the like to a REDIM, then your code reports it correctly.

I also have a lot of code that I have cut/paste DECLARE's from WIN32API.INC, etc. Rather than reporting these functions as "declared but not present", it would be better to parse out the LIB clause and exclude these from the list if they reference one of the common system DLL's (Kernel32, User32, etc).

If I ever manage to find some more time, I'll see if I can help solve the problems.

Keep up the good work!

------------------
Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Lance Edmonds]

Thanks Borje - there is nothing like parsing someone else's writing style to show up the weak points!

When I find time, I'll take a closer look at your GLOBAL analysis technique and maybe borrow some of the logic!



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Lance
PowerBASIC Support
mailto:[email protected][email protected]</A>

[Borje Hagsten]

Lance, good work, but a quick test shows your code doesn't handle Globals
declared in an Include file properly, when they are used in main file.
First gather them, then search in all files need to be done there. Also,
it wrongly reports a bunch of Subs/Functions in include files as un-used.
Probably same kind of fault - main file isn't re-parsed for them.
Also-also, some strange reports for local vars. Example:

  LOCAL hFont AS LONG, ed AS EDM32DATA PTR : ed = GetWindowLong(hWnd, 0)
  'ed it reported as un-used..
 
  DIM tbb(20) AS STATIC TBBUTTON
  DIM IniName(bInList) AS STRING
  'AS is reported as un-used local var for both..

It is a challenge, yes, which is why I decided to rewrite the parser
from scratch. Nothing wrong with the already posted code, but this way,
I feel I can understand things and see the flow better. I'm sometimes
stupid that way and often rewrite perfectly working code from scratch,
just to make myself understand things better..


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[Mike Trader]

Nice app lance!

Thx for finding the silly bug in my code. That was the 2am addition
to the code (can you tell) after reading back through the thread

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Kind Regards
Mike