[llvm] [AMDGPU][NFC][SIInsertWaitcnts] Remove redundant checks for invalidate instructions (PR #166139)

[Stephen Thomas via llvm-commits]

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@@ -530,16 +544,6 @@ class SIInsertWaitcnts {
   // Return the appropriate VMEM_*_ACCESS type for Inst, which must be a VMEM
   // instruction.
   WaitEventType getVmemWaitEventType(const MachineInstr &Inst) const {
-    switch (Inst.getOpcode()) {
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stepthomas wrote:

It's also the case that as far as I can tell, mayAccessVMEMThroughFlat() and mayAccessLDSThroughFlat() will by return true for these instructions, because both functions conservatively return that if there are no memory operands.

https://github.com/llvm/llvm-project/pull/166139