[llvm] [AMDGPU] Widen sub-dword constant loads with dword alignment to match SelectionDAG behavior (PR #184790)

[Arseniy Obolenskiy via llvm-commits]

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@@ -517,20 +517,14 @@ bool AMDGPULateCodeGenPrepare::visitLoadInst(LoadInst &LI) {
   if (!isDWORDAligned(Base))
     return false;
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aobolensk wrote:

Done. Switched to isDereferenceableAndAlignedPointer, added negative tests

https://github.com/llvm/llvm-project/pull/184790