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Hello to those working on RISCV,</div>
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As formerly discussed in <a href="https://github.com/riscv/riscv-crypto/issues/81" title="https://github.com/riscv/riscv-crypto/issues/81">
riscv/riscv-crypto#81</a>, we are currently implementing MC Layer of K extension for LLVM. While setting predicates property for instructions, we encountered the problem that the
<code>Zkg</code> and <code>Zkb</code> feature sets are reusing part but not all instructions from
<code>Zbp</code> and <code>Zbc</code> extensions, as shown in the image in the issue (the same image in attachment; asterisk "means the extensions are expected to be unchanged in the official version"). </div>
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By acknowledging that we cannot simply reuse the whole set of <code>Zbp</code> and
<code>Zbc</code> instructions, this might require us to further group the instructions by modifying the definition file (`.td` TableGen file) of B extension. This seems a bit invasive since it requires to rename things like `HasStdExtZbbOrZbp` into `<b><span style="font-weight:400;background-color:rgb(255, 255, 255);display:inline !important">HasStdExtZbbOrZbpOrZkb</span></b>`,
take instruction <code>ror</code> for example. </div>
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This problem seems applies to both GCC and LLVM in a similar way and I am wondering whether this modification is acceptable, or are there any other ideas?</div>
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Best Regards,</div>
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Qixing Xue (@ksyx)</div>
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