[llvm] [SelectionDAG] Preserve cache hint metadata during legalization (PR #225273)

[Antonio Frighetto via llvm-commits]

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@@ -86,16 +86,11 @@ define i32 @test_load_l2_normal(ptr addrspace(1) %p) {
   ret i32 %v
 }
 
-;-----------------------------------------------------------------------------
-; TODO: Preserve cache hints across DAGCombiner-created memory rewrites.
-; This documents the current store-of-concat-trunc behavior: copied MMOs for
-; the split stores do not retain !mem.cache_hint metadata yet.
-;-----------------------------------------------------------------------------
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antoniofrighetto wrote:

Nit: should we keep a TODO here? (AFAICT there are still places in DAGCombiner where we don't the preserve the hint...)

https://github.com/llvm/llvm-project/pull/225273