[llvm] [VPlan] Handle some VPInstructions in mayReadFromMemory (PR #120058)

[Luke Lau via llvm-commits]

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@@ -117,11 +117,11 @@ define void @test_iv_cost(ptr %ptr.start, i8 %a, i64 %b) {
 ; CHECK-NEXT:    br i1 [[CMP_N11]], label %[[EXIT_LOOPEXIT]], label %[[VEC_EPILOG_SCALAR_PH]]
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lukel97 wrote:

I've added a hint to force vectorization on this loop so it should always calculate the cost now (which is what I think this was originally trying to test)

https://github.com/llvm/llvm-project/pull/120058