[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:

Why do we decode all the standard stuff last, rather than before custom extensions? I'd have thought we want to decode the standard extensions with higher priority than the custom extensions, but maybe not?

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