[llvm] [LoopVectorize] Check for vector-to-scalar casts in legalizer (PR #106244)

[Ramkumar Ramachandra via llvm-commits]

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@@ -0,0 +1,32 @@
+; RUN: opt --force-widen-divrem-via-safe-divisor=false -passes=loop-vectorize -S --debug-only=loop-vectorize < %s 2>&1 | FileCheck %s
+
+; CHECK: LV: Not vectorizing: Found unvectorizable type   %s2 = bitcast <2 x i16> %vec1 to i32
+; CHECK-NOT: Assertion
+
+; Function Attrs: willreturn
+define void @__start() #0 {
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artagnon wrote:

Suggest renaming `__start` to `vector_to_scalar_cast`?

https://github.com/llvm/llvm-project/pull/106244