[llvm] [RISCV] AddEdge between first mask producer and user of V0 (PR #146855)

[Pengcheng Wang via llvm-commits]

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@@ -68,11 +68,33 @@ class RISCVVectorMaskDAGMutation : public ScheduleDAGMutation {
 
   void apply(ScheduleDAGInstrs *DAG) override {
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wangpc-pp wrote:

Update comments at the file header?

https://github.com/llvm/llvm-project/pull/146855