[llvm] [RISCV][VLOPT] Don't reduce the VL is the same as CommonVL (PR #123878)

[Philip Reames via llvm-commits]

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@@ -0,0 +1,20 @@
+; RUN: llc -mtriple=riscv64 -mattr=+v -riscv-enable-vl-optimizer \
+; RUN:   -verify-machineinstrs -debug-only=riscv-vl-optimizer -o - 2>&1 %s | FileCheck %s 
+
+; REQUIRES: asserts
+
+define <vscale x 4 x i32> @same_vl_imm(<vscale x 4 x i32> %passthru, <vscale x 4 x i32> %a, <vscale x 4 x i32> %b) {
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preames wrote:

Though, honestly, this seems like borderline bad practice.  I would be fine with this landing without a dedicated test since it is NFC and "only" improves compile time.  

https://github.com/llvm/llvm-project/pull/123878