[llvm] [AMDGPU] Introduce orderign parameter to atomic intrinsics and introduce new llvm.amdgcn.image.atomic.load intrinsic. (PR #73613)

[via llvm-commits]

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@@ -1154,6 +1154,8 @@ class TargetLoweringBase {
     MaybeAlign align = Align(1);   // alignment
 
     MachineMemOperand::Flags flags = MachineMemOperand::MONone;
+
+    AtomicOrdering ordering = AtomicOrdering::NotAtomic;
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sstipanovic wrote:

I started refactoring this to add `MachineMemOperand` field, but half way through it seemed to me that the code was more complex due to that change. It would require to construct MMO in multiple places in `getTgtMemIntrinsic` which seemed unnecessary to me. I think we now have all the necessary fields to construct MMO. What do you think?

https://github.com/llvm/llvm-project/pull/73613