[llvm] [X86][MC] Support Enc/Dec for EGPR for promoted AMX-TILE instruction (PR #76210)

[via llvm-commits]

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+# RUN: llvm-mc --disassemble %s -triple=x86_64 | FileCheck %s --check-prefixes=ATT
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XinWang10 wrote:

Agree, I think the impl would be cleaner, will do. @KanRobert, these promoted instrs usually only have 1 form for each instrs, it may be doable, and for those has nf or ndd version, we add them one test for each instr, what do you think?

https://github.com/llvm/llvm-project/pull/76210