> On a system which has the bug, it should print two large numbers and two small... | Hacker News

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ls65536 on Feb 6, 2023 | parent | context | favorite | on: Curious Undisclosed Skylake Bug

> On a system which has the bug, it should print two large numbers and two small numbers; on a system which does not have the bug, it should print one large number and three small numbers.

I built and ran the provided code on an AMD Zen 4 CPU, and it printed "two large numbers and two small numbers", so could this bug also be present in other microarchitectures implementing AVX-512 other than Skylake(-X)?

moonchild on Feb 6, 2023 [–]

Interesting; certainly sounds plausible. What happens if you replace '#define COMP "vcompressps"' with '#define COMP "vexpandps"'?

ls65536 on Feb 6, 2023 | [–]

With that change, no meaningful difference in the results from what I can tell: the program still prints two large integers (around 420M) and two smaller ones (around 85M).

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