curating...

2026-08-24 23:12:28 -04:00
1 parent a2de38f187
commit dc635997a9
@@ -1,32 +1,65 @@
 ---
-title: "So I can liter error checks around stuff with little actual cost,"
+title: "Another round of getting optimized error checking."
 type: archive
 source: twitter
-source_url: "https://x.com/NOTimothyLottes/status/2076893128515112995"
+source_url: "https://x.com/NOTimothyLottes/status/2076888631508107561"
 author: "NOTimothyLottes"
 handle: NOTimothyLottes
-post_id: "2076893128515112995"
+post_id: "2076888631508107561"
 date: 2026-07-14
-archived: 2026-08-23
-draft: true
+archived: 2026-08-24
+draft: false
 tags:
  - archive
  - twitter
  - NOTimothyLottes
-description: "So I can liter error checks around stuff with little actual cost,"
+description: "Another round of getting optimized error checking."
 in_reply_to: ""
 ---

 ## Source

- URL: https://x.com/NOTimothyLottes/status/2076893128515112995
+- URL: https://x.com/NOTimothyLottes/status/2076888631508107561
 - Author: NOTimothyLottes (@NOTimothyLottes)
- Posted: 2026-07-14 04:54:43
+- Posted: 2026-07-14 04:36:51

 ## Thread

 **1/**

+Another round of getting optimized error checking. Disassembly [after syscall] shows that it works. 
+(1.) Volatile store __LINE__
+(2.) Volatile store "error code"
+(3.) TEST if error
+(4.) Conditional forward branch on error [static prediction untaken]
+AS_MINIMAL_AS_ONE_CAN_GET
+
+![](https://pbs.twimg.com/media/HNKWJZqXwAADMnN?format=png&name=orig)
+
+**2/**
+
+A macro cheat sheet to try to explain how it works ...
+
+![](https://pbs.twimg.com/media/HNKX5DhXIAE1BG6?format=png&name=orig)
+
+**3/**
+
+I have a collection of force inline wrappers that test returns from syscalls/functions for error and return the return. These all leverage builtin_expect so the compiler knows to make them fall through in the common case.
+
+![](https://pbs.twimg.com/media/HNKY8qFXQAAF9Db?format=png&name=orig)
+
+**4/**
+
+Those force inlines call Err() on terminal error. The Err() function ensures the {__LINE__, error} stores are visible, then triggers the console drawing code to kill the app with printed error. Then it sleeps until the termination.
+
+![](https://pbs.twimg.com/media/HNKZyFTXYAAETnU?format=png&name=orig)
+
+**5/**
+
+Compiler eventually screws up, but at least it gets the fast path correct, and the slow error path gets an extra call. Effectively it conditionally forward branches to a distant call to Err() instead of just branching to the Err().
+
+**6/**
+
 So I can liter error checks around stuff with little actual cost,
 (1.) Two stores
 (2.) A CMP or TEST
@@ -0,0 +1,35 @@
+---
+title: "@kenpex [Asimov vibes intensify]"
+type: archive
+source: twitter
+source_url: "https://x.com/abductee_org/status/1650685805776732160"
+author: "Michael Sänger (💉 3/2)"
+handle: abductee_org
+post_id: "1650685805776732160"
+date: 2023-04-25
+archived: 2026-08-24
+draft: false
+tags:
+  - archive
+  - twitter
+  - kenpex
+description: "@kenpex [Asimov vibes intensify]"
+in_reply_to: ""
+parent_post_id: "1650678968255913985"
+---
+
+## Source
+
+- URL: https://x.com/abductee_org/status/1650685805776732160
+- Author: Michael Sänger (💉 3/2) (@abductee_org)
+- Posted: 2023-04-25 02:18:59
+
+## Branch
+
+**1/**
+
+@kenpex [Asimov vibes intensify]
+
+## Related
+
+- Spine: [[archive/threads/kenpex/2023-04-25-nerds-are-crazy-https-git-sr-ht-vdupras-duskos]]
@@ -29,6 +29,8 @@ in_reply_to: ""

 Nerds are crazy https://git.sr.ht/~vdupras/duskos

+Branches: [[archive/threads/kenpex/2023-04-25-nerds-are-crazy-https-git-sr-ht-vdupras-duskos/2023-04-25-abductee_org-asimov-vibes-intensify]], [[archive/threads/kenpex/2023-04-25-nerds-are-crazy-https-git-sr-ht-vdupras-duskos/2023-04-25-streleav-indeed-any-thoughts-on-how-agi-could-help-the]], [[archive/threads/kenpex/2023-04-25-nerds-are-crazy-https-git-sr-ht-vdupras-duskos/2023-04-26-ChristerEricson-i-was-curious-about-what-it-would-take-to]], [[archive/threads/kenpex/2023-04-25-nerds-are-crazy-https-git-sr-ht-vdupras-duskos/2023-04-26-SebAaltonen-some-people-have-too-much-time-for-hobby-projects]], [[archive/threads/kenpex/2023-04-25-nerds-are-crazy-https-git-sr-ht-vdupras-duskos/2023-04-26-ErikHaliewicz-this-is-actually-a-fantastic-project-though]], [[archive/threads/kenpex/2023-04-25-nerds-are-crazy-https-git-sr-ht-vdupras-duskos/2023-04-27-JaceCear-the-what-if-were-in-an-apocalypse-part-is-very]]
+
 **2/**

@kenpex I find the context hilarious, but Forth as asm-level-yet-very-usable-mini-OS has been done, as the boot firmware for OLPC (http://laptop.org) for many years. Looks like it's currently open sourced as https://github.com/openbios/openbios.