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

[Austin Kerbow via llvm-commits]

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@@ -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) {
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kerbowa wrote:

> What's the difference between this and TII::isSchedulingBoundary?
isSchedulingBoundary creates divisions between scheduling regions, it separates and defines independent ScheduleDAGs. isGlobalMemoryObject controls dependency edges within a ScheduleDAG.

> Also wondering if we could treat these like isPosition
In what way? You mean treat these as debug info instead of instructions?


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