[llvm] [AMDGPU] Enable unaligned scratch accesses (PR #110219)

[Matt Arsenault via llvm-commits]

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@@ -387,8 +387,9 @@ bool GCNTTIImpl::isLegalToVectorizeMemChain(unsigned ChainSizeInBytes,
   // them later if they may access private memory. We don't have enough context
   // here, and legalization can handle it.
   if (AddrSpace == AMDGPUAS::PRIVATE_ADDRESS) {
-    return (Alignment >= 4 || ST->hasUnalignedScratchAccess()) &&
-      ChainSizeInBytes <= ST->getMaxPrivateElementSize();
+    return (Alignment >= 4 || ST->hasUnalignedScratchAccessEnabled() ||
+            ST->enableFlatScratch()) &&
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arsenm wrote:

Same here 

https://github.com/llvm/llvm-project/pull/110219