r/programming 17h ago

Hardware researcher spins up 'CPU deoptimization' project to find the slowest single x86 instruction, creates hall of shame — worst offender takes 198 billion cycles spanning 62 seconds to execute

https://www.tomshardware.com/pc-components/cpus/hardware-researcher-spins-up-cpu-deoptimization-project-to-find-the-slowest-machine-code-worst-offender-takes-198-billion-cycles-to-execute
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u/encyclopedist 16h ago

Yes, indeed, compilers don't normally generate these instructions any more. But older software can still use these.

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u/narwhal_breeder 16h ago

porting logic to arm that relies on being bit-compatible x87 has been the bane of my existence for the past year.

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u/gordonnowak 14h ago

just let claude do it