[llvm] [DirectX] Lower `llvm.lifetime.*` intrinsics to stores when DXIL version is lower than 1.6 (PR #147432)

[Farzon Lotfi via llvm-commits]

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@@ -16,3 +16,6 @@ define void @test_legal_lifetime()  {
   call void @llvm.lifetime.end.p0(i64 4, ptr nonnull %accum.i.flat)
   ret void
 }
+
+!dx.valver = !{!0}
+!0 = !{i32 1, i32 5}
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farzonl wrote:

Can you add a comment here so its clear this is how we are specifying dxil version.

https://github.com/llvm/llvm-project/pull/147432