{ "root_post_id": "2076893128515112995", "posts": [ { "post_id": "2076888631508107561", "author": "NOTimothyLottes", "handle": "NOTimothyLottes", "text": "Another round of getting optimized error checking. Disassembly [after syscall] shows that it works. \n(1.) Volatile store __LINE__\n(2.) Volatile store \"error code\"\n(3.) TEST if error\n(4.) Conditional forward branch on error [static prediction untaken]\nAS_MINIMAL_AS_ONE_CAN_GET", "timestamp": "2026-07-14 04:36:51", "media_urls": [ "https://pbs.twimg.com/media/HNKWJZqXwAADMnN?format=png&name=orig" ], "reply_to_id": null, "quote_of_id": null, "metrics": { "reply_count": 2, "repost_count": 0, "like_count": 8, "view_count": 1903 } }, { "post_id": "2076890340057878586", "author": "NOTimothyLottes", "handle": "NOTimothyLottes", "text": "A macro cheat sheet to try to explain how it works ...", "timestamp": "2026-07-14 04:43:38", "media_urls": [ "https://pbs.twimg.com/media/HNKX5DhXIAE1BG6?format=png&name=orig" ], "reply_to_id": "2076888631508107561", "quote_of_id": null, "metrics": { "reply_count": 2, "repost_count": 0, "like_count": 7, "view_count": 567 } }, { "post_id": "2076891161898143906", "author": "NOTimothyLottes", "handle": "NOTimothyLottes", "text": "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.", "timestamp": "2026-07-14 04:46:54", "media_urls": [ "https://pbs.twimg.com/media/HNKY8qFXQAAF9Db?format=png&name=orig" ], "reply_to_id": "2076890340057878586", "quote_of_id": null, "metrics": { "reply_count": 1, "repost_count": 0, "like_count": 5, "view_count": 350 } }, { "post_id": "2076892038314741815", "author": "NOTimothyLottes", "handle": "NOTimothyLottes", "text": "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.", "timestamp": "2026-07-14 04:50:23", "media_urls": [ "https://pbs.twimg.com/media/HNKZyFTXYAAETnU?format=png&name=orig" ], "reply_to_id": "2076891161898143906", "quote_of_id": null, "metrics": { "reply_count": 1, "repost_count": 0, "like_count": 2, "view_count": 143 } }, { "post_id": "2076892591216341089", "author": "NOTimothyLottes", "handle": "NOTimothyLottes", "text": "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().", "timestamp": "2026-07-14 04:52:35", "media_urls": [], "reply_to_id": "2076892038314741815", "quote_of_id": null, "metrics": { "reply_count": 1, "repost_count": 0, "like_count": 2, "view_count": 449 } }, { "post_id": "2076893128515112995", "author": "NOTimothyLottes", "handle": "NOTimothyLottes", "text": "So I can liter error checks around stuff with little actual cost,\n(1.) Two stores\n(2.) A CMP or TEST\n(3.) An ignored on no-error branch on the first execution! [this code almost never runs 2 times].", "timestamp": "2026-07-14 04:54:43", "media_urls": [], "reply_to_id": "2076892591216341089", "quote_of_id": null, "metrics": { "reply_count": 0, "repost_count": 0, "like_count": 3, "view_count": 419 } } ], "source_url": "https://x.com/NOTimothyLottes/status/2076893128515112995" }