[llvm] [AMDGPU] Fix lack of LDS DMA check in the AA handling (PR #75249)

[Jay Foad via llvm-commits]

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@@ -3656,8 +3656,8 @@ bool SIInstrInfo::areMemAccessesTriviallyDisjoint(const MachineInstr &MIa,
   // underlying address space, even if it was lowered to a different one,
   // e.g. private accesses lowered to use MUBUF instructions on a scratch
   // buffer.
-  if (isDS(MIa)) {
-    if (isDS(MIb))
+  if (isDS(MIa) || isLDSDMA(MIa)) {
+    if (isDS(MIb) || isLDSDMA(MIb))
       return checkInstOffsetsDoNotOverlap(MIa, MIb);
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jayfoad wrote:

Does ` checkInstOffsetsDoNotOverlap` handle LDSDMA correctly?  I think not. At best, it will just check that the BUF/FLAT addresses do not overlap, and ignore the LDS part.

https://github.com/llvm/llvm-project/pull/75249