[mlir][IR] Hash result types in OperationFingerPrint

[springerm]

Summary

Result types were not considered in OperationFingerPrint. This can lead to missing IR dumps when running with shouldPrintAfterOnlyOnChange and false positives in D144552.

[mehdi_amini]

Nice finding!

[rriddle]

LGTM

mlir/lib/IR/OperationSupport.cpp

topOp->walk([&](Operation *op) {
     //   - Location
     addDataToHash(hasher, op->getLoc().getAsOpaquePointer());
     //   - Operands
     for (Value operand : op->getOperands())
       addDataToHash(hasher, operand);
     //   - Successors
     for (unsigned i = 0, e = op->getNumSuccessors(); i != e; ++i)
       addDataToHash(hasher, op->getSuccessor(i));
+    //   - Result types
+    for (Type t : op->getResultTypes())
+      addDataToHash(hasher, t);
   });
   hash = hasher.result();
 }