frontpage.
newsnewestaskshowjobs

Made with ♥ by @iamnishanth

Open Source @Github

fp.

Open in hackernews

NetBSD 10.x Kernel Math_emulation

https://mezzantrop.wordpress.com/2025/02/04/netbsd-10-x-kernel-math_emulation/
57•jaypatelani•11mo ago

Comments

__s•11mo ago
This sort of platform support is cool, but it's a sign when existing hardware is failing & the platform support is shown with emulation

If uou run ancient hardware, use ancient software. Preservation efforts in keeping an image of that ancient software available makes sense (which becomes harder as modern build systems pull from network to build)

boricj•11mo ago
Sometimes it's useful to be able to run modern software on ancient hardware.

I once made an image of a hard disk so old it wouldn't work on anything newer than a Pentium. I plugged in a USB PCI card+USB stick and booted a modern-ish at the time Debian Live CD.

It took over 5 minutes to decompress just the kernel and a hour to copy the HDD to the USB stick, but it did work. The time delta between the oldest and newest component on that system was well over 20 years, sometimes this is what you have to do with what you have on hand.

jmclnx•11mo ago
I saw this a few days ago, nice, especially since Linux is dropping support for older hardware. Even OpenBSD is slowly limiting i386 (32bit) support:

https://www.openbsd.org/i386.html

NetBSD so far has no plans to drop 32bit x86 support, and it is always nice to be able to run a modern UN*X on older hardware. IIRC, porting NetBSD to a new platform is quite easy when compared to other systems. This is due to how their HAL (hardware abstraction layer) is designed.

Today I saw in the OpenBSD @misc mailing list one of the issues they are having with i386 is rust is too large for them to compile on a i386 system. That means software packages that need rust are being removed from their packages.

This does not affect NetBSD because they allow cross-compiling of everything on their systems.

anthk•11mo ago
OpenBSD runs perfectly fine under i386, atom user there.

I don't care about Rust and it's killer app Firefox, there are tons of alternatives for i686. From Luakit to Vimb.

johnklos•11mo ago
Compiling rust on a 32 bit system is a several year old issue. Enough of us made a fuss about it that the rust build system was fixed enough that this became possible again.

If rust doesn't compile on an i386 system with 4 gigs of memory, then that's very odd. I don't know much about rust, but I was still able to get it to compile for earmv6hf on a Raspberry Pi 3 with 1 gig of RAM. Perhaps the OpenBSD people need to try some of the things we've already figured out.

https://mail-index.netbsd.org/tech-pkg/2025/05/09/msg031137....

makz•11mo ago
Cannot find the mail in @misc you are talking about
jmclnx•11mo ago
Here it is

https://marc.info/?l=openbsd-misc&m=174696055709421&w=2

anthk•11mo ago
On math FP emulation, by looking up the code it seems pretty close to the code from Robert F. Illyes for Forth 83.

Forth implementation in Eforth it's like this:

    ( FORTH-83 FLOATING POINT.
      ----------------------------------
      COPYRIGHT 1985 BY ROBERT F. ILLYES
            PO BOX 2516, STA. A
            CHAMPAIGN, IL 61820
            PHONE: 217/826-2734  )     HEX
    : ZERO  OVER 0= IF DROP 0 THEN ;
    : FNEGATE 8000 XOR ZERO ;
    : FABS  7FFF AND ;
    : NORM  >R 2DUP OR
            IF BEGIN DUP 0< NOT
               WHILE D2* R> 1- >R
               REPEAT SWAP 0< - ?DUP
               IF R> ELSE 8000 R> 1+ THEN
            ELSE R> DROP THEN ;
    : F2*   1+ ZERO ;
    : F*    ROT + 4000 - >R UM* R> NORM ;
    : FSQ   2DUP F* ;
    : F2/   1- ZERO ;
    : UM/   DUP >R UM/MOD SWAP R>
            OVER 2* 1+ U< SWAP 0< OR - ;
    : F/    ROT SWAP - 4000 + >R
            0 ROT ROT 2DUP U<
            IF   UM/ R> ZERO
            ELSE >R D2/ FABS R> UM/ R> 1+
            THEN ;
    : ALIGN 20 MIN 0 DO D2/ LOOP ;
    : RALIGN 1- ?DUP IF ALIGN THEN
            1 0 D+ D2/ ;
    : FSIGN FABS OVER 0< IF >R DNEGATE R>
            8000 OR THEN ;
    : F+    ROT 2DUP >R >R FABS SWAP FABS -
            DUP IF DUP 0<
                    IF   ROT SWAP  NEGATE
                         R> R> SWAP >R >R
                    THEN 0 SWAP RALIGN
            THEN SWAP 0 R> R@ XOR 0<
            IF   R@ 0< IF 2SWAP THEN D-
                 R> FSIGN ROT SWAP NORM
            ELSE D+ IF 1+ 2/ 8000 OR R> 1+
                    ELSE R> THEN THEN ;
    : F-    FNEGATE F+ ;
    : F<    F- 0< SWAP DROP ;
    ( FLOATING POINT INPUT/OUTPUT ) DECIMAL
    CREATE PL 3 , HERE  ,001 , ,   ,010 , ,
              ,100 , ,            1,000 , ,
            10,000 , ,          100,000 , ,
         1,000,000 , ,       10,000,000 , ,
       100,000,000 , ,    1,000,000,000 , ,
    : TENS  2* 2* LITERAL + 2@ ;     HEX
    : PLACES PL ! ;
    : SHIFTS FABS 4010 - DUP 0< NOT
            ABORT" TOO BIG" NEGATE ;
    : F#    >R PL @ TENS DROP UM* R> SHIFTS
            RALIGN PL @ ?DUP IF 0 DO # LOOP
            ". HOLD THEN #S ROT SIGN ;
    : TUCK  SWAP OVER ;
    : F.    TUCK <# F# #> TYPE SPACE ;
    : DFLOAT 4020 FSIGN NORM ;
    : F     DFLOAT POINT TENS DFLOAT F/ ;
    : FCONSTANT F 2CONSTANT ;
    : FLOAT DUP 0< DFLOAT ;
    : -+    DROP SWAP 0< IF NEGATE THEN ;
    : FIX   TUCK 0 SWAP SHIFTS RALIGN -+ ;
    : INT   TUCK 0 SWAP SHIFTS  ALIGN -+ ;
    1.      FCONSTANT ONE DECIMAL
    34.6680 FCONSTANT X1
    -57828. FCONSTANT X2
    2001.18 FCONSTANT X3
    1.4427  FCONSTANT X4
    : EXP   2DUP INT DUP >R FLOAT F-
            F2* X2 2OVER FSQ X3 F+ F/
            2OVER F2/ F-     X1 F+ F/
            ONE F+ FSQ R> + ;
    : FEXP  X4 F* EXP ;
    : GET   BL WORD DUP 1+ C@ "- = TUCK -
            0 0 ROT CONVERT DROP -+ ;
    : E     F GET >R R@ ABS 13301 4004 */MOD
            >R FLOAT 4004 FLOAT F/ EXP R> +
            R> 0< IF F/ ELSE F* THEN ;
    : E.    TUCK FABS 16384 TUCK -
            4004 13301 */MOD >R
            FLOAT 4004 FLOAT F/ EXP F*
            2DUP ONE F<
            IF 10 FLOAT F* R> 1- >R THEN
            <# R@ ABS 0 #S R> SIGN 2DROP
            "E HOLD F# #>     TYPE SPACE ;
the float abs function it's literally the same, operating over the same bits.

On the lack of floating point on some arch, Forth itself (even ANS Forth) encourages you to follow a fixed point philosophy unless it's absolutely neccesary, because you can always scale up the magnitudes on big 32 bit machines.

And Pi can be prise enough by using scaling with 'double' (for 16 bit machines) numbers:

100.000 355 113 m*/ d. 314159 ok

SudoSuccubus•11mo ago
This is the most worthless thing in the world. Why would anybody give a rat's fucking ass about a third? Not even a third rate like a 10th rate. Fucking operating system having math support. Oh wow! Congratulations! Now you can go ahead and support computers from 1985 now
2000UltraDeluxe•11mo ago
It's a hobbyist project. It doesn't need any "worth" apart from the joy the author got from it.

Kudos to the author for doing this _and_ sharing it with the world.

anthk•11mo ago
This is about software emulated FP. OFC NetBSD used the FP module in CPU's since long ago.

Also, FP is not math, it's just a kind of math. And even Forth users will use a fixed point before going into float. With 32 bits, they will just scale the point and call it a day.

And seasoned Forth users will just use quotient arithmetic and output fractional parts as two items in the stack.

Async Rust never left the MVP state

https://tweedegolf.nl/en/blog/237/async-rust-never-left-the-mvp-state
180•pjmlp•3h ago•86 comments

Should I Run Plain Docker Compose in Production in 2026?

https://distr.sh/blog/running-docker-in-production/
56•pmig•4d ago•35 comments

Bun is being ported from Zig to Rust

https://github.com/oven-sh/bun/commit/46d3bc29f270fa881dd5730ef1549e88407701a5
549•SergeAx•10h ago•382 comments

Empty Screenings – Finds AMC movie screenings with few or no tickets sold

https://walzr.com/empty-screenings
167•MrBuddyCasino•6h ago•131 comments

Lessons for Agentic Coding: What should we do when code is cheap?

https://www.dbreunig.com/2026/05/04/10-lessons-for-agentic-coding.html
79•ingve•4h ago•61 comments

When everyone has AI and the company still learns nothing

https://www.robert-glaser.de/when-everyone-has-ai-and-the-company-still-learns-nothing/
18•youngbrioche•1h ago•3 comments

Hand Drawn QR Codes

https://sethmlarson.dev/hand-drawn-qr-codes
122•jollyjerry•7h ago•22 comments

Google Chrome silently installs a 4 GB AI model on your device without consent

https://www.thatprivacyguy.com/blog/chrome-silent-nano-install/
297•john-doe•3h ago•302 comments

How OpenAI delivers low-latency voice AI at scale

https://openai.com/index/delivering-low-latency-voice-ai-at-scale/
413•Sean-Der•15h ago•129 comments

CVE-2026-31431: Copy Fail vs. rootless containers

https://www.dragonsreach.it/2026/05/04/cve-2026-31431-copy-fail-rootless-containers/
116•averi•7h ago•50 comments

Farewell to a Giant of Botany

https://nautil.us/farewell-to-a-giant-of-botany-1280409
35•Brajeshwar•2d ago•0 comments

Train Your Own LLM from Scratch

https://github.com/angelos-p/llm-from-scratch
272•kristianpaul•7h ago•29 comments

Agent Skills

https://addyosmani.com/blog/agent-skills/
267•BOOSTERHIDROGEN•13h ago•127 comments

Why I Created phpc.tv

https://afilina.com/why-phpc-tv
25•luu•1d ago•3 comments

Mouse Pointer as a Mere Mortal

https://unsung.aresluna.org/mouse-pointer-as-a-mere-mortal/
31•zdw•2d ago•9 comments

The Frog for Whom the Bell Tolls

https://sethmlarson.dev/the-frog-for-whom-the-bell-tolls
16•anujbans•3h ago•5 comments

Does Employment Slow Cognitive Decline? Evidence from Labor Market Shocks

https://www.nber.org/papers/w35117
303•littlexsparkee•19h ago•282 comments

Securing a DoD contractor: Finding a multi-tenant authorization vulnerability

https://www.strix.ai/blog/how-strix-found-zero-auth-vulnerability-dod-backed-startup
200•bearsyankees•17h ago•82 comments

pgxbackup: Continuity Support for pgBackRest

https://thebuild.com/blog/2026/05/01/pgxbackup-continuity-support-for-pgbackrest/
56•Wingy•2d ago•9 comments

Redis array: short story of a long development process

https://antirez.com/news/164
287•antirez•20h ago•102 comments

When networking doesn't work

https://www.os2museum.com/wp/when-networking-doesnt-work/
69•kencausey•14h ago•11 comments

Gap between national food production and food-based dietary guidance (2025)

https://www.nature.com/articles/s43016-025-01173-4
65•simonebrunozzi•22h ago•47 comments

Talking to strangers at the gym

https://thienantran.com/talking-to-35-strangers-at-the-gym/
1375•thitran•23h ago•655 comments

Formatting a 25M-line codebase overnight

https://stripe.dev/blog/formatting-an-entire-25-million-line-codebase-overnight-the-rubyfmt-story
171•r00k•15h ago•88 comments

Kids bypass age verification with fake moustaches

https://www.theregister.com/2026/05/04/uk_online_safety_act_age_checks_subvert/
113•dreadsword•6h ago•78 comments

Biscuit

https://github.com/yattsu/biscuit
54•unixfg•8h ago•3 comments

2-D Mathematical Curves

https://www.2dcurves.com/
37•the-mitr•6h ago•2 comments

1966 Ford Mustang Converted into a Tesla with Working 'Full Self-Driving'

https://electrek.co/2026/05/02/tesla-1966-mustang-ev-conversion-full-self-driving/
173•Brajeshwar•19h ago•131 comments

Setting up server monitoring for a Rails app on Hatchbox

https://blog.appsignal.com/2026/04/30/setting-up-server-monitoring-for-a-rails-app-on-hatchbox.html
4•andreigaspar•1d ago•1 comments

Testing Mac OS on the Apple Network Server 2.0 ROMs

http://oldvcr.blogspot.com/2026/05/testing-macos-on-apple-network-server.html
87•zdw•1d ago•17 comments