[llvm] [AMDGPU][MISched] Allow memory ops of different base pointers to be clustered (PR #140674)

[Matt Arsenault via llvm-commits]

================
@@ -585,10 +585,24 @@ bool SIInstrInfo::shouldClusterMemOps(ArrayRef<const MachineOperand *> BaseOps1,
     const MachineInstr &FirstLdSt = *BaseOps1.front()->getParent();
     const MachineInstr &SecondLdSt = *BaseOps2.front()->getParent();
 
-    if (!DisableDiffBasePtrMemClustering) {
+    if (EnableDiffBasePtrMemClustering) {
       // Only consider memory ops from same addrspace for clustering
       if (!memOpsHaveSameAddrspace(FirstLdSt, BaseOps1, SecondLdSt, BaseOps2))
         return false;
+
+      // Don't cluster scalar and vecter memory ops
----------------
arsenm wrote:

```suggestion
      // Don't cluster scalar and vector memory ops
```

https://github.com/llvm/llvm-project/pull/140674