[llvm] [RISCV] Use LiveIntervals::extendToIndices to extend AVL in insertVSETVLI (PR #97512)

[Pengcheng Wang via llvm-commits]

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@@ -1161,10 +1161,7 @@ void RISCVInsertVSETVLI::insertVSETVLI(MachineBasicBlock &MBB,
     // isn't always the case, e.g. PseudoVMV_X_S doesn't have an AVL operand or
     // we've taken the AVL from the VL output of another vsetvli.
     LiveInterval &LI = LIS->getInterval(AVLReg);
-    // Need to get non-const VNInfo
-    VNInfo *VNI = LI.getValNumInfo(Info.getAVLVNInfo()->id);
-    LI.addSegment(LiveInterval::Segment(
-        VNI->def, LIS->getInstructionIndex(*MI).getRegSlot(), VNI));
+    LIS->extendToIndices(LI, {LIS->getInstructionIndex(*MI).getRegSlot()});
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wangpc-pp wrote:

Why do we need to call `getRegSlot` again? Does `getInstructionIndex` return the `SlotIndex`?

https://github.com/llvm/llvm-project/pull/97512