[llvm] [AMDGPU] Add target hook to isGlobalMemoryObject (PR #112781)

[Austin Kerbow via llvm-commits]

================
@@ -549,7 +549,7 @@ void ScheduleDAGInstrs::addVRegUseDeps(SUnit *SU, unsigned OperIdx) {
 
 /// Returns true if MI is an instruction we are unable to reason about
 /// (like a call or something with unmodeled side effects).
-static inline bool isGlobalMemoryObject(MachineInstr *MI) {
----------------
kerbowa wrote:

I don't know if an existing instruction property would work, isPosition makes an instruction a scheduling boundary and would split the block as far as the scheduler is concerned.

https://github.com/llvm/llvm-project/pull/112781