[llvm] Add FPMR register and update dependencies of FP8 instructions (PR #102910)

[via llvm-commits]

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@@ -922,7 +922,9 @@ defm FCVT_Z2Z_HtoB  : sme2_fp8_cvt_vg2_single<"fcvt",   0b0>;
 defm BFCVT_Z2Z_HtoB : sme2_fp8_cvt_vg2_single<"bfcvt",  0b1>;
 defm FCVT_Z4Z_StoB  : sme2_fp8_cvt_vg4_single<"fcvt",   0b0>;
 defm FCVTN_Z4Z_StoB : sme2_fp8_cvt_vg4_single<"fcvtn",  0b1>;
+} // [HasSME2, HasFP8]
 
+let Uses=[FPCR], Predicates = [HasSME2, HasFP8] in {
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Lukacma wrote:

I was questioning whether to make this change at all. It seems like all FP instructions are missing dependency on FPCR and that needs to be fixed as separate task. In this patch I focused only on FP8 instructions, that's why I updated it like this, with the hope that whoever ends up updating all the FP ones will make changes for this as appropriate. But maybe the better approach would be to leave fscale unchanged and fix it when fixing other fp instructions

https://github.com/llvm/llvm-project/pull/102910