Hello , I need to know whether someone has fast routines to calculate crc32 of let's say 64 k buffer. Any help would be appreciated Pianoman ----- Original Message ----- From: <[EMAIL PROTECTED]> To: <fpc-pascal@lists.freepascal.org> Sent: Sunday, April 16, 2006 12:02 PM Subject: fpc-pascal Digest, Vol 20, Issue 18
> Send fpc-pascal mailing list submissions to > fpc-pascal@lists.freepascal.org > > To subscribe or unsubscribe via the World Wide Web, visit > http://lists.freepascal.org/mailman/listinfo/fpc-pascal > or, via email, send a message with subject or body 'help' to > [EMAIL PROTECTED] > > You can reach the person managing the list at > [EMAIL PROTECTED] > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of fpc-pascal digest..." > > > Today's Topics: > > 1. Re: Division by Zero - not raised exception (Sasa Zeman) > 2. Re: Division by Zero - not raised exception (Florian Klaempfl) > 3. Re: Division by Zero - not raised exception (Sasa Zeman) > 4. Re: Division by Zero - not raised exception (Florian Klaempfl) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Sun, 16 Apr 2006 10:16:27 +0200 > From: "Sasa Zeman" <[EMAIL PROTECTED]> > Subject: Re: [fpc-pascal] Division by Zero - not raised exception > To: "FPC-Pascal users discussions" <fpc-pascal@lists.freepascal.org> > Message-ID: <[EMAIL PROTECTED]> > Content-Type: text/plain; charset="iso-8859-1" > > > > FPC 2.0.2 do not rasie exception on integer/floats division by Zero, > which > > > is suitable for calucaltion I currently developing. Instead, division > > > return infinity: > > > > > > writeln(1/0) -> +inf > > > writeln(1.0/0) -> +inf > > Already fixed. > > Unfortunatelly, bug still persists when division is performed with > constants. > Please take a look bug report #5018 for details. > > > ------------------------------ > > Message: 2 > Date: Sun, 16 Apr 2006 10:23:06 +0200 > From: Florian Klaempfl <[EMAIL PROTECTED]> > Subject: Re: [fpc-pascal] Division by Zero - not raised exception > To: FPC-Pascal users discussions <fpc-pascal@lists.freepascal.org> > Message-ID: <[EMAIL PROTECTED]> > Content-Type: text/plain; charset=ISO-8859-1 > > Sasa Zeman wrote: > >>> FPC 2.0.2 do not rasie exception on integer/floats division by Zero, > > which > >>> is suitable for calucaltion I currently developing. Instead, division > >>> return infinity: > >>> > >>> writeln(1/0) -> +inf > >>> writeln(1.0/0) -> +inf > >> Already fixed. > > > > Unfortunatelly, bug still persists when division is performed with > > constants. > > Please take a look bug report #5018 for details. > > We don't consider this as a bug, it's for delphi compatibility reasons. > These expressions are evaluated at compile time, so it's something > differnt. If you want to get an error, compile with -Cr. > > ------------------------------ > > Message: 3 > Date: Sun, 16 Apr 2006 11:34:45 +0200 > From: "Sasa Zeman" <[EMAIL PROTECTED]> > Subject: Re: [fpc-pascal] Division by Zero - not raised exception > To: "FPC-Pascal users discussions" <fpc-pascal@lists.freepascal.org> > Message-ID: <[EMAIL PROTECTED]> > Content-Type: text/plain; charset="iso-8859-1" > > > We don't consider this as a bug, it's for delphi compatibility reasons. > > These expressions are evaluated at compile time, so it's something > > differnt. If you want to get an error, compile with -Cr. > > The -Cr will point on error in the code, however, enabling range checking > will also affect on global speed performance. > > Definition in documentation (RTL.pdf): > " > 29.20 EDivByZero > 29.20.1 Description > EDivByZero is used when the operating system or CPU signals a division by > zero error. > " > As defined, reported issue is a bug. As well globaly, in consistency terms. > > Far I can see, the core of the problem is in definiton of Infinity constant > as 1.0/0.0 and NaN with ln(-1.0) or 0.0/0.0 Perhaps this is necessary to > avoid problem with probably difference between different CPU/FPUs. However, > IEEE specification should be followed by all of them and bits manipulation > to perform infinity should be enough, instead to calculate it (as is > performed currently). > > > ------------------------------ > > Message: 4 > Date: Sun, 16 Apr 2006 11:40:35 +0200 > From: Florian Klaempfl <[EMAIL PROTECTED]> > Subject: Re: [fpc-pascal] Division by Zero - not raised exception > To: FPC-Pascal users discussions <fpc-pascal@lists.freepascal.org> > Message-ID: <[EMAIL PROTECTED]> > Content-Type: text/plain; charset=ISO-8859-1 > > Sasa Zeman wrote: > >> We don't consider this as a bug, it's for delphi compatibility reasons. > >> These expressions are evaluated at compile time, so it's something > >> differnt. If you want to get an error, compile with -Cr. > > > > The -Cr will point on error in the code, however, enabling range checking > > will also affect on global speed performance. > > The program won't compile with -Cr. > > > > > Definition in documentation (RTL.pdf): > > " > > 29.20 EDivByZero > > 29.20.1 Description > > EDivByZero is used when the operating system or CPU signals a division by > > zero error. > > " > > As defined, reported issue is a bug. As well globaly, in consistency terms. > > ... operating system or CPU ... > but not the compiler ;) > > The point is: this div by zero is encountered at compilation time. > The other option is to stop compilation always. Executing the operation > at run time is useless imo and a waste of CPU cycles. > > > > > Far I can see, the core of the problem is in definiton of Infinity constant > > as 1.0/0.0 and NaN with ln(-1.0) or 0.0/0.0 > > No. These constants are defined in const blocks. A const block couldn't > throw an exception. > > > Perhaps this is necessary to > > avoid problem with probably difference between different CPU/FPUs. However, > > IEEE specification should be followed by all of them and bits manipulation > > to perform infinity should be enough, instead to calculate it (as is > > performed currently). > > > > _______________________________________________ > > fpc-pascal maillist - fpc-pascal@lists.freepascal.org > > http://lists.freepascal.org/mailman/listinfo/fpc-pascal > > > > > ------------------------------ > > _______________________________________________ > fpc-pascal maillist - fpc-pascal@lists.freepascal.org > http://lists.freepascal.org/mailman/listinfo/fpc-pascal > > End of fpc-pascal Digest, Vol 20, Issue 18 > ****************************************** > > > __________ Informacia od NOD32 1.1490 (20060415) __________ > > Tato sprava bola preverena antivirusovym systemom NOD32. > http://www.eset.sk > > _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal
