[llvm] [RISCV] Introduce VLOptimizer pass (PR #108640)

[Pengcheng Wang via llvm-commits]

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@@ -103,6 +103,10 @@ static cl::opt<bool> EnableVSETVLIAfterRVVRegAlloc(
     cl::desc("Insert vsetvls after vector register allocation"),
     cl::init(true));
 
+static cl::opt<bool> EnableVLOptimizer("riscv-enable-vloptimizer",
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wangpc-pp wrote:

riscv-enable-vl-optimizer?

https://github.com/llvm/llvm-project/pull/108640