[llvm] [RISCV] Add XSfmm pseudo instruction and vset* insertion support (PR #143068)

[Luke Lau via llvm-commits]

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@@ -1671,6 +1780,10 @@ void RISCVInsertVSETVLI::coalesceVSETVLIs(MachineBasicBlock &MBB) const {
   };
 
   for (MachineInstr &MI : make_early_inc_range(reverse(MBB))) {
+    // TODO: Support XSfmm.
+    if (RISCVII::hasTWidenOp(MI.getDesc().TSFlags) ||
+        RISCVInstrInfo::isXSfmmVectorConfigInstr(MI))
+      continue;
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lukel97 wrote:

Can the xsfmm config instructions modify VL or VTYPE? If so should they set `NextMI = nullptr`

https://github.com/llvm/llvm-project/pull/143068