 | Lars Fosdal on Security alarm provider Woonve… |
 | Thomas Mueller on Question got closed in May 202… |
 | Thaddy de Koning on Formulier voor bewindvoerders… |
| Thaddy de Koning on Formulier voor bewindvoerders… |
| Thaddy de Koning on Formulier voor bewindvoerders… |
Posted by jpluimers on 2020/06/16
[WayBack] A Tale of Many Divisions – Naive Prime Factorization Across a Handful of Architectures
Source code: [WayBack] GitHub – blu/euclid: An extremely naive prime factorizer
Via: [WayBack] Blu looks at how a small piece of code with divisions surprisingly behave on various architecture: #Arm, #MIPS, and #x86. – Jean-Luc Aufranc – Google+
–jeroen
Posted in Assembly Language, C++, Development, Software Development | Leave a Comment »
Posted by jpluimers on 2019/05/22
Cool: [WayBack] Insentricity :: Kermit on the JAIR 8080 ::
Repository: [WayBack] FozzTexx/Kermit-CPM: Columbia University’s Kermit for CP/M
–jeroen
Posted in Assembly Language, Development, History, Software Development | Leave a Comment »
Posted by jpluimers on 2019/03/20
It looks like AVX can be a curse most of the times. Below are some (many) links that lead me to this conclusion, based on a thread started by Kelly Sommers.
Running AVX instructions will affect the processor frequency, which means that non-AVX code will slow down, so you will only benefit when the gain of using AVX code outweighs the non-AVX loss on anything running on that processor in the same time frame.
In practice, this means you need to long term gain from AVX on many cores. If you don’t, then the performance penalty on all cores, including the initial AVX performance, will degrade, often a lot (dozens of %).
why doesn’t radfft support AVX on PC?
Kelly raised a bunch of interesting questions and remarks because of the above:
I collected the above links because of [WayBack] GitHub – maximmasiutin/FastMM4-AVX: FastMM4 fork with AVX support and multi-threaded enhancements (faster locking), where it is unclear which parts of the gains are because of AVX and which parts are because of other optimizations. It looks like that under heavy loads on data center like conditions, the total gain is about 30%. The loss for traditional processing there has not been measured, but from the above my estimate it is at least 20%.
Full tweets below.
Posted in Assembly Language, Development, Software Development, x64, x86 | Leave a Comment »
Posted by jpluimers on 2019/02/28
Geek pr0n at [WayBack] performance – Why is this C++ code faster than my hand-written assembly for testing the Collatz conjecture? – Stack Overflow
Via: [WayBack] Very nice #Geekpr0n “Why is C++ faster than my hand-written assembly code?” The comments are of high quality i… – Jan Wildeboer – Google+
–jeroen
Posted in Assembly Language, C, C++, Development, Software Development, x64, x86 | Leave a Comment »
Posted by jpluimers on 2018/09/11
On x86/x64/ARM/…:
It’s where the function is going to return to, not where it came from.
And:
Bonus chatter: This reminds me of a quirk of the 6502 processor: When it pushed the return address onto the stack, it actually pushed the return address minus one. This is an artifact of the way the 6502 is implemented, but it results in the nice feature that the stack trace gives you the line number of the call instruction.
Of course, this is all hypothetical, because 6502 debuggers didn’t have fancy features like stack traces or line numbers.
Source: [WayBack] Remember that in a stack trace, the addresses are return addresses, not call addresses – The Old New Thing
Which resulted in these comments at [WayBack] CC +mos6502 – Jeroen Wiert Pluimers – Google+:
- mos6502: And don’t forget the crucial difference in PC on 6502 between RTS and RTI!
- Jeroen Wiert Pluimers: +mos6502 I totally forgot about that one. Thanks for reminding me
<<Note that unlike RTS, the return address on the stack is the actual address rather than the address-1.>>
References:
[WayBack] 6502.org: Tutorials and Aids – RTI
RTI retrieves the Processor Status Word (flags) and the Program Counter from the stack in that order (interrupts push the PC first and then the PSW).
Note that unlike RTS, the return address on the stack is the actual address rather than the address-1.
[WayBack] 6502.org: Tutorials and Aids – RTS
RTS pulls the top two bytes off the stack (low byte first) and transfers program control to that address+1. It is used, as expected, to exit a subroutine invoked via JSR which pushed the address-1.
RTS is frequently used to implement a jump table where addresses-1 are pushed onto the stack and accessed via RTS eg. to access the second of four routines.
–jeroen
Posted in 6502, 6502 Assembly, Assembly Language, Development, History, Software Development, The Old New Thing, Windows Development, x64, x86 | Leave a Comment »
Posted by jpluimers on 2018/08/17
It seems there are a few, but only loading the binary is the sure method to know what the process will be using: [WayBack] How to check if a binary is 32 or 64 bit on Windows? – Super User and [WayBack] How do I determine if a .NET application is 32 or 64 bit? – Stack Overflow.
Details in the answers of these questions, here are a few highlights:
dumpbin.exe with the /headers option.sigcheck.exe from SysInternals.file utility (e.g. from cygwin, which comes with msysgit) will distinguish between 32- and 64-bit executables.7z.exe on the PE file (Exe or DLL) in question which gives you a CPU line.File detail is a way to find out if a binary is 32 bit or 64 bit.CORFLAGS utility can be used to determine how a .NET application will run.–jeroen
Search terms: win64, win32, x64, x86_64, x86
Posted in Assembly Language, Development, Power User, Windows, x64, x86 | Leave a Comment »
Posted by jpluimers on 2018/06/12
Interesting: [WayBack] Grammar Zoo – Browsable Borland Delphi Assembler Grammar.
It is very complete, including constructs like the [WayBack] special directives VMTOFFSET and DMTINDEX for Delphi virtual and dynamic methods.
You can contribute to it using https://github.com/slebok/zoo/tree/master/zoo/assembly/delphi
–jeroen
Posted in Assembly Language, Delphi, Development, Software Development, x86 | Leave a Comment »
Posted by jpluimers on 2018/02/07
Via [WayBack] Hi all,I’m a bit stuck here with a “simple” task.Looks like Outlook 2016 doesn’t supports “MAPISendMail”, at least, if i trigger this, Thunderbird… – Attila Kovacs – Google+:
Basically only MAPISendMail works cross architecture and only if you fill all fields.
This edited [WayBack] email – MAPI Windows 7 64 bit – Stack Overflow answer by [WayBack] epotter is very insightful (thanks [WayBack] Rik van Kekem – Google+):
Calls to MAPISendMail should work without a problem.
For all other MAPI method and function calls to work in a MAPI application, the bitness (32 or 64) of the MAPI application must be the same as the bitness of the MAPI subsystem on the computer that the application is targeted to run on.
In general, a 32-bit MAPI application must not run on a 64-bit platform (64-bit Outlook on 64-bit Windows) without first being rebuilt as a 64-bit application.
For a more detailed explanation, see the MSDN page on Building MAPI Applications on 32-Bit and 64-Bit Platforms
–jeroen
Posted in Delphi, Delphi x64, Development, Office, Outlook, Power User, Software Development, x86 | Leave a Comment »
Posted by jpluimers on 2017/11/02
Quoted in full because even 2.5 years later, it’s just too funny:
- Python: What if everything was a dict?
- Java: What if everything was an object?
- JavaScript: What if everything was a dict *and* an object?
- C: What if everything was a pointer?
- APL: What if everything was an array?
- Tcl: What if everything was a string?
- Prolog: What if everything was a term?
- LISP: What if everything was a pair?
- Scheme: What if everything was a function?
- Haskell: What if everything was a monad?
- Assembly: What if everything was a register?
- Coq: What if everything was a type/proposition?
- COBOL: WHAT IF EVERYTHING WAS UPPERCASE?
- C#: What if everything was like Java, but different?
- Ruby: What if everything was monkey patched?
- Pascal: BEGIN What if everything was structured? END
- C++: What if we added everything to the language?
- C++11: What if we forgot to stop adding stuff?
- Rust: What if garbage collection didn’t exist?
- Go: What if we tried designing C a second time?
- Perl: What if shell, sed, and awk were one language?
- Perl6: What if we took the joke too far?
- PHP: What if we wanted to make SQL injection easier?
- VB: What if we wanted to allow anyone to program?
- VB.NET: What if we wanted to stop them again?
- Forth: What if everything was a stack?
- ColorForth: What if the stack was green?
- PostScript: What if everything was printed at 600dpi?
- XSLT: What if everything was an XML element?
- Make: What if everything was a dependency?
- m4: What if everything was incomprehensibly quoted?
- Scala: What if Haskell ran on the JVM?
- Clojure: What if LISP ran on the JVM?
- Lua: What if game developers got tired of C++?
- Mathematica: What if Stephen Wolfram invented everything?
- Malbolge: What if there is no god?
–jeroen
Posted in .NET, APL, Assembly Language, BASIC, C, C#, C++, COBOL, Development, EPS/PostScript, Fun, Go (golang), Java, Java Platform, JavaScript/ECMAScript, LISP, Makefile, Pascal, Perl, PHP, Python, Quotes, Ruby, Rust, Scala, Scripting, Smalltalk, Software Development, T-Shirt quotes, TCL, Turbo Prolog, VB.NET, Visual BASIC, XML/XSD, XSLT | Leave a Comment »
Posted by jpluimers on 2017/06/26
–jeroen
Posted in Assembly Language, CP/M, Development, History, Software Development, Z80 | Leave a Comment »
The Wiert Corner - irregular stream of stuff 