Post Ax44C4asrQBojHOee0 by jbqueru@floss.social
 (DIR) More posts by jbqueru@floss.social
 (DIR) Post #Ax2kVbsp7i17EdrmOe by jbqueru@floss.social
       2025-08-10T18:49:34Z
       
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       Me, looking at the 8008/8080/Z80 instruction sets: "bah, why do you need conditional calls and conditional returns when the conditional jumps are already more than enough?"Me, coding in 68000: "I really wish I had conditional calls and conditional returns, relying on conditional jumps makes the code harder to read than necessary."I am never happy.#RetroComputing #Assembly
       
 (DIR) Post #Ax2kVd5GevZ6xWhEQq by tomjennings@tldr.nettime.org
       2025-08-11T00:27:15Z
       
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       @jbqueru Alan Turings original ACE design has intentionally zero conditional instructions. He calculated branches. It was not popular. The ACEs that got built had conditional branches. But the jerks took out all the amazing logical and bit manipulation stuff he'd put in there, hard learned lessons from code breaking. But pedants didn't see the value and he could not properly justify them, due to secrecy.
       
 (DIR) Post #Ax362lPcoV5XNmrKd6 by jbqueru@floss.social
       2025-08-11T04:28:31Z
       
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       @tomjennings That's definitely an interesting approach, though one that might be hurting branch prediction on modern processors.8008 didn't have it, 8080 has PCHL, named JP (HL) in Z80... and RISC-V has JALR, as if it needed to be made more confusing (and on RISC-V that's the only way to do jumps longer than 1MB if I'm reading correctly).
       
 (DIR) Post #Ax44C4asrQBojHOee0 by jbqueru@floss.social
       2025-08-11T04:32:03Z
       
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       @tomjennings And 8008 is more microcontroller than microprocessor, its stack doesn't store arbitrary data, so you can't just push the jump address and RET to it.
       
 (DIR) Post #Ax44C6BmvhItg1fdo0 by tomjennings@tldr.nettime.org
       2025-08-11T15:42:30Z
       
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       @jbqueru Oh yeah it's a terrible chip! Lol.... But I saw an 8008 boot and run Linux.  At the Tear Down event at Crowd Supply this past June. This guy made some minimal hardware (finding family chips quite the hunt), wrote a minimal I think risc-5 emulator, got Linux to run on that. It takes most of a day to boot but I saw it running.