[llvm] AMDGPU: Move attributor into optimization pipeline (PR #83131)

[Matt Arsenault via llvm-commits]

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@@ -678,6 +678,12 @@ void SIFrameLowering::emitEntryFunctionPrologue(MachineFunction &MF,
         break;
       }
     }
+
+    // FIXME: We can spill incoming arguments and restore at the end of the
+    // prolog.
+    if (!ScratchWaveOffsetReg)
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arsenm wrote:

Kind of. One test hit the assert due to the sgpr limiting attribute 

https://github.com/llvm/llvm-project/pull/83131