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A comment on Nvidia to Acquire Arm for $40B. Parent comment

Re:Nvidia to Acquire Arm for $40B by rrss on Monday September 14, 2020 @12:30PM (#24472065)
WMMX was exposed via the ARM coprocessor mechanism (so it was permitted by the architecture). The coprocessor stuff was removed in ARMv8.
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Re:Nvidia to Acquire Arm for $40B by my123 on Monday September 14, 2020 @12:33PM (#24472095)
Now custom instructions are directly on the regular instruction space...

(+ there's the can of worms of target-specific MSRs being writable from user-space, Apple does this as part of APRR to flip the JIT region from RW- to R-X and vice-versa without going through a trip to the kernel. That also has the advantage that the state is modifiable per-thread)

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Re:Nvidia to Acquire Arm for $40B by Followerer on Monday September 14, 2020 @02:44PM (#24473594)
In ARMv8 you have a much cleaner mechanism through system registers(MSR/MRS).
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Re:Nvidia to Acquire Arm for $40B by saagarjha on Monday September 14, 2020 @03:56PM (#24474403)
Apple has been using system registers for years already. AMX is interesting because it's actual instruction encodings that are unused by the spec.
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