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

[Paul Walker 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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paulwalker-arm wrote:

That works for me.  As you say, SME is not in great shape in this regard so the FP8 instructions are not making anything worse.

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