[llvm] [RISCV] Consolidate some DecoderNamespaces for standard extensions. (PR #128954)

[Sam Elliott via llvm-commits]

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@@ -721,6 +711,11 @@ DecodeStatus RISCVDisassembler::getInstruction32(MCInst &MI, uint64_t &Size,
   TRY_TO_DECODE_FEATURE_ANY(XRivosFeatureGroup, DecoderTableXRivos32, "Rivos");
 
   TRY_TO_DECODE(true, DecoderTable32, "RISCV32");
+  TRY_TO_DECODE(true, DecoderTableRV32GPRPair32,
+                "RV32GPRPair (rv32 and GPR pairs)");
+  TRY_TO_DECODE(true, DecoderTableZfinx32, "Zfinx (Float in Integer)");
+  TRY_TO_DECODE(true, DecoderTableZdinxRV32GPRPair32,
+                "ZdinxRV32GPRPair (rv32 and Double in Integer)");
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lenary wrote:

I'm less concerned for speed, more for "we should prioritise decoding the standard extensions", which feels like a good principle. It sounds like doing so might require changing how we implemented Xqcisim, so I can do the reordering as a follow-up.

https://github.com/llvm/llvm-project/pull/128954