[clang] [llvm] [AMDGPU] Emit a waitcnt instruction after each memory instruction (PR #79236)

[Pierre van Houtryve via cfe-commits]

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@@ -641,6 +644,9 @@ class SIMemoryLegalizer final : public MachineFunctionPass {
   bool expandAtomicCmpxchgOrRmw(const SIMemOpInfo &MOI,
                                 MachineBasicBlock::iterator &MI);
 
+  bool GFX9InsertWaitcntForPreciseMem(MachineFunction &MF);
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Pierre-vh wrote:

Agreed, this should definitely be a virtual function such as `insertWaitcntForPreciseMem` and let the CacheControl implementation do what is needed. This is just emulating what `CacheControl` already does

https://github.com/llvm/llvm-project/pull/79236