[llvm] [VPlan] Fall back to scalar epilogue if possible when EVL isn't legal (PR #150908)

[Luke Lau via llvm-commits]

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@@ -122,35 +122,34 @@ for.end:
 define i32 @mul(ptr %a, i64 %n, i32 %start) {
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lukel97 wrote:

These reduction tests are affected because there's no scalable lowering for multiply reductions on RISC-V, and so we can't use EVL because it doesn't supported fixed VFs. 

https://github.com/llvm/llvm-project/pull/150908