[llvm] [RISCV] Reduce the VL of both operands in VMERGE_VVM (PR #144759)

[Min-Yih Hsu via llvm-commits]

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@@ -3063,9 +3063,9 @@ define <vscale x 4 x i32> @vmv_v_x(<vscale x 4 x i32> %a, i32 %x, iXLen %vl) {
 define <vscale x 1 x i8> @vmv_v_v(<vscale x 1 x i8> %a, <vscale x 1 x i8> %b, <vscale x 1 x i8> %c, <vscale x 1 x i1> %m, iXLen %vl) {
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mshockwave wrote:

Interestingly, with this patch, the NOVLOPT produces the same result as VLOPT. So I think we offload some of the optimizations from VL optimizer.

https://github.com/llvm/llvm-project/pull/144759