[llvm] [RISCV] Eliminate dead li after emitting VSETVLIs (PR #65934)

[Yeting Kuo via llvm-commits]

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@@ -487,10 +487,7 @@ class VSETVLIInfo {
       if (getAVLReg() == RISCV::X0)
         return true;
       if (MachineInstr *MI = MRI.getVRegDef(getAVLReg());
-          MI && MI->getOpcode() == RISCV::ADDI &&
-          MI->getOperand(1).isReg() && MI->getOperand(2).isImm() &&
-          MI->getOperand(1).getReg() == RISCV::X0 &&
-          MI->getOperand(2).getImm() != 0)
+          MI && RISCV::isLoadSImm12(*MI, /*NonZero*/ true))
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yetingk wrote:

Is it a good idea to use `RISCVInstrInfo::isAddImmediate` after #72356 landed?

https://github.com/llvm/llvm-project/pull/65934