[llvm] [RISCV][VLOPT] Allow propagation even when VL isn't VLMAX (PR #112228)

[Pengcheng Wang via llvm-commits]

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@@ -31,6 +31,44 @@ using namespace llvm;
 
 namespace {
 
+struct VLInfo {
+  VLInfo(const MachineOperand &VLOp) {
+    IsImm = VLOp.isImm();
+    if (IsImm)
+      Imm = VLOp.getImm();
+    else
+      Reg = VLOp.getReg();
+  }
+
+  Register Reg;
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wangpc-pp wrote:

Is it possible to use `std::variant` here?

https://github.com/llvm/llvm-project/pull/112228