[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 +1,299 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc %s -o - -mtriple=riscv64 -mattr=+v -run-pass=riscv-vl-optimizer -verify-machineinstrs | FileCheck %s
+
+---
+name: test
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preames wrote:

I don't know that adding this is a good idea.  This won't show up as a test failure if this ever fails, it will only show up as a long running test.  I'm not sure that's likely to get noticed.

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