[PATCH] D119921: [RISCV] Teach VSETVLInsert to optimize vsetvli for ScalarMoveInstr

[Chenbing.Zheng via Phabricator via llvm-commits]

Chenbing.Zheng added inline comments.


================
Comment at: llvm/lib/Target/RISCV/RISCVInsertVSETVLI.cpp:1092
           }
-          if (NeedInsertVSETVLI)
+          if (ScalarMoveVSETVLI) {
+            if (NewInfo.hasAVLImm() &&
----------------
jacquesguan wrote:
> As the former comment, the scalar move instruction may share a VSETVLI with one or some other instructions, so in this situation, we could not only think about the scalar move instruction, other instructions may care about the LMUL.
Yer, if scalar move instruction share a VSETVLI with others, we do not optimize this case. Because as you said, that would cause the error. ScalarMoveVSETVLI will be nullptr in this case.


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https://reviews.llvm.org/D119921