Writing Passes for the MQSS¶

Adding your pass¶

Two types of passes can be added : Dialect-Agnostic and Dialect-specific
The dialect agnostic passes should be added within lib/common/Passes, whereas, dialect-specific passes should be added within lib/mqss-catalyst/lib/MQSSCatalystPasses (for catalyst-quantum) and lib/mqss-cudaq/lib/MQSSQuakePasses (for quake).
A key step in adding your pass is pass registration. This ensures that the passes can be found by the targets mqss-cudaq-opt and ``````mqss-catalyst-opt```.
1. To register a pass we need to make additions to 2 files Transforms.h and Transforms.td. These files can be found within lib/mqss-catalyst/include/MQSSCatalystPasses and lib/mqss-cudaq/include/MQSSQuakePasses.
2. Here is an example of pass registration within lib/mqss-cudaq/include/MQSSQuakePasses/Transforms.td:
```
  def CommonNormalizeArgAnglePass : Pass<"CommonNormalizeArgAnglePass", "mlir::ModuleOp"> {
    let summary = "Normalize Arg angle of RX, RY, RZ gates. ";

    let description = [{
      Normalize Arg angle of RX, RY, RZ gates.
    }];

    let constructor = "mqss_cudaq::opt::CommonNormalizeArgAnglePass()";
  }
```
The pass is registered for the mqss-cudaq-opt target. Since the pass is dialect agnostic, the same pass can be registered for the mqss-catalyst-opt target by changing the namespace mqss_cudaq::opt to mqss_catalyst::opt within the constructor. 3. In Transforms.h within the mqss_cudaq::opt and mqss_catalyst::opt namespaces, the following should be added:
```
   std::unique_ptr<mlir::Pass> CommonNormalizeArgAnglePass();
```

Writing Passes for the MQSS¶

Adding your pass¶

Pass Structure¶

Adding a Dialect¶