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   :blobcatflower: (methyltheobromine@netzsphaere.xyz)'s status on Sunday, 17-Nov-2024 00:13:59 JST :blobcatflower:
   why is branching so expensive on arm..
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     iced depresso (icedquinn@blob.cat)'s status on Sunday, 17-Nov-2024 00:13:58 JST iced depresso

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     @lucy its 'expensive' everywhere, isn't it?
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     snacks (snacks@netzsphaere.xyz)'s status on Sunday, 17-Nov-2024 00:15:11 JST snacks

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     @lucy prob depends on the specific cpu? Gba is ooold
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     snacks (snacks@netzsphaere.xyz)'s status on Sunday, 17-Nov-2024 00:16:21 JST snacks

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     • snacks
     @lucy modern branch prediction is prob way better everywhere
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     :blobcatflower: (methyltheobromine@netzsphaere.xyz)'s status on Sunday, 17-Nov-2024 00:17:56 JST :blobcatflower:

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     • snacks
     @snacks this thing doesn't have branch prediction afaik lol
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     snacks (snacks@netzsphaere.xyz)'s status on Sunday, 17-Nov-2024 00:18:42 JST snacks

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     @lucy if it has a pipeline and branches it has some form of branch prediction, even if it's just "always take the branch"
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     snacks (snacks@netzsphaere.xyz)'s status on Sunday, 17-Nov-2024 00:24:04 JST snacks

     in reply to
     @lucy it prob does out of order execution?
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     :blobcatflower: (methyltheobromine@netzsphaere.xyz)'s status on Sunday, 17-Nov-2024 00:24:06 JST :blobcatflower:

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     • snacks
     @snacks still it only knows where to go after the execute stage so the pipeline is resetted, wasting 2 additional cycles. or does it somehow already know where to go at fetch? doubt.
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     snacks (snacks@netzsphaere.xyz)'s status on Sunday, 17-Nov-2024 00:29:38 JST snacks

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     • snacks
     @lucy but then, it's basically avr-tier just with 32-bit registers and bus so maybe not
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     [SUYA] ひみつ :blabcatverified: (ivesen@miniwa.moe)'s status on Sunday, 17-Nov-2024 00:43:10 JST [SUYA] ひみつ :blabcatverified:

     in reply to
     @lucy easier to answer why it isn't so expensive on x86, where both branches can be taken and the correct outcome chosen later. This would certainly never lead to spectre/meltdown, because that would be a silly mistake to make
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     snacks (snacks@netzsphaere.xyz)'s status on Sunday, 17-Nov-2024 00:48:20 JST snacks

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     • snacks
     @lucy https://www.copetti.org/writings/consoles/game-boy-advance/#tab-2-2-the-pipeline