[llvm] [X86] Early exit MIR AMX passes when AMX is unused (PR #94989)

[Phoebe Wang via llvm-commits]

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@@ -237,11 +237,15 @@ void X86PreTileConfig::collectShapeInfo(MachineInstr &MI) {
 }
 
 bool X86PreTileConfig::runOnMachineFunction(MachineFunction &MF) {
+  X86MachineFunctionInfo *X86FI = MF.getInfo<X86MachineFunctionInfo>();
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phoebewang wrote:

Just found we have `set/hasHasVirtualTileReg` interfaces. We can remove it and replace with `X86FI->getAMXProgModel() == AMXProgModelEnum::ManagedRA` too.

https://github.com/llvm/llvm-project/pull/94989