Hackers' Pub

Syntax	Description	Examples
`"` keyword `"`	Finds the string within quotes, including spaces. Case-insensitive. (Escape quotes inside with `\"`)	`"Hackers' Pub"`
`from:` handle	Finds content written by the specified user.	`from:hongminhee` `from:hongminhee@hollo.social`
`lang:` ISO 639-1	Finds content written in the specified language.	`lang:en`
`#` tag	Finds content with the specified tag. Case-insensitive.	`#HackersPub`
condition condition	Finds content that satisfies both conditions on either side of the space (logical AND).	`"Hackers' Pub" lang:en`
condition `OR` condition	Finds content that satisfies at least one of the conditions on either side of the OR operator (logical OR).	`#HackersPub OR "Hackers' Pub" lang:en`
`(` condition `)`	Combines the operators within the parentheses first.	`(#HackersPub OR "Hackers' Pub" OR "Hackers Pub") lang:en`

David Chisnall (*Now with 50% more sarcasm!*) @david_chisnall@infosec.exchange

2/17/2026, 8:07:52 AM

Quiet public

@koakumaSun Microdevil Pte Ltd @rygorousFabian Giesen @regehrJohn Regehr

Intel has a tradition that every ten years they build an architecture that it is impossible to write a compiler for. The iAPX432, i860, and Itanium were each iterations of this. The next one was a GPU architecture with a two-dimensional register file (amazing for hand-coded assembly kernels, not great for anything that needed to merge lowering of vector permutes with register allocation). I didn’t pay attention to what they did most recently, I presume they made some AI accelerator that has amazingly high FLOPS numbers on paper and is impossible to target from MLIR.

Fabian Giesen @rygorous@mastodon.gamedev.place

2/17/2026, 8:21:08 PM

Quiet public

@david_chisnallDavid Chisnall (*Now with 50% more sarcasm!*) @koakumaSun Microdevil Pte Ltd @regehrJohn Regehr The iAPX 432 from what I can tell was not at all impossible to write compilers for, but as per Bob Colwell who wrote a bunch of papers dissecting the 432 for his PhD, the compiler team did not get along with the HW team and explicitly didn't want the effort to succeed. https://www.sigmicro.org/media/oralhistories/colwell.pdf p. 51

[..] one particular night that summer, | was with some friends, and we went up to this bar where I struck up a conversation with some random guy | didn't know sitting next to me. He asked me what | was doing at Intel for the summer. | said "I'm a grad student doing some research on the 432." "Really? What kinds of things are you finding?" | said "Well, I'm finding that there's a huge disconnect between the software and the hardware. | mean the hardware should be capable of doing a procedure call much quicker than it's actually doing, for instance, it's taking many hundreds of clock cycles. And in other places, I'm seeing all kind of wastage from the compiler just setting variables that never get used, classic stuff you just don't do." And the guy said "Really? | mean tell me more about that part."

Eventually, | said "Okay, who are you? You know way too much about this technology." He tells me "I'm the leader of the compiler team." And I said "In that case | probably just fatally offended you." He said "No, not at all because | know we generate bad code and | don't care." He said "We don't like the 432 hardware team." And | thought "Oh my God, there is no hope that this project is going to work when you have the two main casts killing each other." He said "That hardware team never listened to us compiler folks At some point we decided that we'd live up to the letter of the contract but beyond that? No."

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