[llvm] [RISCV] Add late optimization pass for riscv (PR #133256)

[Michael Maitland via llvm-commits]

================
@@ -319,6 +328,10 @@ class RISCVInstrInfo : public RISCVGenInstrInfo {
                                const MachineInstr &MI2) const;
   bool hasReassociableVectorSibling(const MachineInstr &Inst,
                                     bool &Commuted) const;
+
+  /// Return true if the instruction is a load immediate instruction (i.e.
+  /// ADDI x0, imm).
+  static bool isLoadImm(const MachineInstr *MI, int64_t &Imm);
----------------
michaelmaitland wrote:

Good idea in making it static. Need to declare it in header or can we keep it all in the cpp file and not a part of RISCVInstrInfo class?

https://github.com/llvm/llvm-project/pull/133256