[llvm] [LV] Return Invalid from getLegacyCost when instruction cost forced. (PR #154543)

[Florian Hahn via llvm-commits]

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@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
-; RUN: opt -p loop-vectorize -force-target-instruction-cost=1 -S %s | FileCheck %s
+; RUN: opt -p loop-vectorize -force-target-instruction-cost=100 -S %s | FileCheck %s
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fhahn wrote:

I know I originally suggested 100, but if a smaller value also works that would probably be good

https://github.com/llvm/llvm-project/pull/154543