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A comment on An introduction to reverse-engineering x86 microcode and writing it. Parent comment

Re:An introduction to reverse-engineering x86 microcode and ... by userbinator on Friday December 29, 2017 @12:06PM (#16030438)
It's a combination of microcode and hardwired logic that's common now --- hardwired simple instructions, microcoded complex ones.
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Re:An introduction to reverse-engineering x86 microcode and ... by bogomipz on Friday December 29, 2017 @03:45PM (#16031861)
In the slide during the presentation at the 10:23 minute mark he shows the short decoders under the instruction register and I believe even those simple instructions are all made up of micro-ops that need to be looked up in ROM as well.
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Re:An introduction to reverse-engineering x86 microcode and ... by monocasa on Sunday December 31, 2017 @01:55PM (#16042034)
The CPU only executes micro ops, but the "vector decoder" is the only one that uses microcode to sequence the ops.
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