[llvm] [LV] Move check if any vector insts will be generated to VPlan. (PR #96622)

[via llvm-commits]

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@@ -1,7 +1,7 @@
 ; RUN: opt -S -passes=loop-vectorize -mtriple=s390x-linux-gnu -vectorizer-min-trip-count=8 < %s | FileCheck %s
 
 define i32 @main(i32 %arg, ptr nocapture readnone %arg1) #0 {
-;CHECK: vector.body:
+; CHECK-NOT: vector.body:
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ayalz wrote:

A more accurate observation if any instruction was vectorized causes LV to avoid (pretending to) vectorizing this loop?

https://github.com/llvm/llvm-project/pull/96622