🐛 Rename CtrlOp region to region to avoid hiding trait method getBody() (#1430)

## Description

Unfortunately, this became a little bit more cumbersome to figure out
than expected.
The automatically generated getter for the parameter "body" was hiding
one of the trait interface methods. These methods do have a slightly
different signature (`getBody()` returns a `Block*` and
`getBodyRegion()` accepts an index parameter) which can lead to
confusion and an inconsistent API.

An alternative to this proposal could be simply the name "region"
because `getRegion()` of the `OneRegion` trait has the same signature
and thus the override would probably not be noticed. However, there
would be two identical implementations for this method and this could
make debugging harder.

The downside to the current solution is that there are now three
functions to access the region: `getRegion()` (by `OneRegion`),
`getBodyRegion()` (by `SingleBlock`) and `getCtrlBodyRegion()` (by
getter).

## Checklist:

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- [ ] The pull request only contains commits that are focused and
relevant to this change.
- [ ] I have added appropriate tests that cover the new/changed
functionality.
- [ ] I have updated the documentation to reflect these changes.
- [ ] I have added entries to the changelog for any noteworthy
additions, changes, fixes, or removals.
- [ ] I have added migration instructions to the upgrade guide (if
needed).
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- [ ] I have reviewed my own code changes.

Author: taminob

CHANGELOG.md

@@ -11,7 +11,7 @@ This project adheres to [Semantic Versioning], with the exception that minor rel
 
 ### Added
 
-- ✨ Add initial infrastructure for new QC and QCO MLIR dialects ([#1264], [#1402]) ([**@burgholzer**], [**@denialhaag**])
+- ✨ Add initial infrastructure for new QC and QCO MLIR dialects ([#1264], [#1402], [#1428], [#1430]) ([**@burgholzer**], [**@denialhaag**], [**@taminob**])
 - ✨ Return device handle from `add_dynamic_device_library` for direct backend creation ([#1381]) ([**@marcelwa**])
 - ✨ Add IQM JSON support for job submission in Qiskit-QDMI Backend ([#1375], [#1382]) ([**@marcelwa**], [**@burgholzer**])
 - ✨ Add authentication support for QDMI sessions with token, username/password, auth file, auth URL, and project ID parameters ([#1355]) ([**@marcelwa**])
@@ -294,6 +294,8 @@ _📚 Refer to the [GitHub Release Notes](https://github.com/munich-quantum-tool
 
 <!-- PR links -->
 
+[#1430]: https://github.com/munich-quantum-toolkit/core/pull/1430
+[#1428]: https://github.com/munich-quantum-toolkit/core/pull/1428
 [#1415]: https://github.com/munich-quantum-toolkit/core/pull/1415
 [#1414]: https://github.com/munich-quantum-toolkit/core/pull/1414
 [#1413]: https://github.com/munich-quantum-toolkit/core/pull/1413

mlir/include/mlir/Dialect/QC/IR/QCOps.td

@@ -948,8 +948,8 @@ def CtrlOp : QCOp<"ctrl",
     }];
 
     let arguments = (ins Arg<Variadic<QubitType>, "the control qubits", [MemRead, MemWrite]>:$controls);
-    let regions = (region SizedRegion<1>:$body);
-    let assemblyFormat = "`(` $controls `)` $body attr-dict `:` type($controls)";
+    let regions = (region SizedRegion<1>:$region);
+    let assemblyFormat = "`(` $controls `)` $region attr-dict `:` type($controls)";
 
     let extraClassDeclaration = [{
         [[nodiscard]] UnitaryOpInterface getBodyUnitary();

mlir/include/mlir/Dialect/QCO/IR/QCOOps.td

@@ -1067,10 +1067,10 @@ def CtrlOp : QCOOp<"ctrl", traits =
     let arguments = (ins Arg<Variadic<QubitType>, "the control qubits", [MemRead]>:$controls_in,
                      Arg<Variadic<QubitType>, "the target qubits", [MemRead]>:$targets_in);
     let results = (outs Variadic<QubitType>:$controls_out, Variadic<QubitType>:$targets_out);
-    let regions = (region SizedRegion<1>:$body);
+    let regions = (region SizedRegion<1>:$region);
     let assemblyFormat = [{
         `(` $controls_in `)` $targets_in
-        $body attr-dict `:`
+        $region attr-dict `:`
         `(` `{` type($controls_in) `}` ( `,` `{` type($targets_in)^ `}` )? `)`
         `->`
         `(` `{` type($controls_out) `}` ( `,` `{` type($targets_out)^ `}` )? `)`

mlir/lib/Conversion/QCOToQC/QCOToQC.cpp

@@ -777,8 +777,8 @@ struct ConvertQCOCtrlOp final : OpConversionPattern<qco::CtrlOp> {
     auto qcoOp = rewriter.create<qc::CtrlOp>(op.getLoc(), qcControls);
 
     // Clone body region from QCO to QC
-    auto& dstRegion = qcoOp.getBody();
-    rewriter.cloneRegionBefore(op.getBody(), dstRegion, dstRegion.end());
+    auto& dstRegion = qcoOp.getRegion();
+    rewriter.cloneRegionBefore(op.getRegion(), dstRegion, dstRegion.end());
 
     // Replace the output qubits with the same QC references
     rewriter.replaceOp(op, adaptor.getOperands());

mlir/lib/Conversion/QCToQCO/QCToQCO.cpp

@@ -1127,8 +1127,8 @@ struct ConvertQCCtrlOp final : StatefulOpConversionPattern<qc::CtrlOp> {
     state.targetsIn.try_emplace(state.inCtrlOp, qcoTargets);
 
     // Clone body region from QC to QCO
-    auto& dstRegion = qcoOp.getBody();
-    rewriter.cloneRegionBefore(op.getBody(), dstRegion, dstRegion.end());
+    auto& dstRegion = qcoOp.getRegion();
+    rewriter.cloneRegionBefore(op.getRegion(), dstRegion, dstRegion.end());
 
     rewriter.eraseOp(op);
     return success();

mlir/lib/Dialect/QC/IR/Modifiers/CtrlOp.cpp

@@ -109,7 +109,7 @@ struct CtrlInlineGPhase final : OpRewritePattern<CtrlOp> {
 } // namespace
 
 UnitaryOpInterface CtrlOp::getBodyUnitary() {
-  return llvm::dyn_cast<UnitaryOpInterface>(&getBody().front().front());
+  return llvm::dyn_cast<UnitaryOpInterface>(&getBody()->front());
 }
 
 size_t CtrlOp::getNumQubits() { return getNumTargets() + getNumControls(); }
@@ -173,7 +173,7 @@ void CtrlOp::build(OpBuilder& odsBuilder, OperationState& odsState,
 }
 
 LogicalResult CtrlOp::verify() {
-  auto& block = getBody().front();
+  auto& block = *getBody();
   if (block.getOperations().size() != 2) {
     return emitOpError("body region must have exactly two operations");
   }

mlir/lib/Dialect/QCO/IR/Modifiers/CtrlOp.cpp

@@ -152,7 +152,7 @@ struct CtrlInlineId final : OpRewritePattern<CtrlOp> {
 } // namespace
 
 UnitaryOpInterface CtrlOp::getBodyUnitary() {
-  return llvm::dyn_cast<UnitaryOpInterface>(&getBody().front().front());
+  return llvm::dyn_cast<UnitaryOpInterface>(&getBody()->front());
 }
 
 size_t CtrlOp::getNumQubits() { return getNumTargets() + getNumControls(); }
@@ -272,7 +272,7 @@ void CtrlOp::build(OpBuilder& odsBuilder, OperationState& odsState,
 }
 
 LogicalResult CtrlOp::verify() {
-  auto& block = getBody().front();
+  auto& block = *getBody();
   if (block.getOperations().size() != 2) {
     return emitOpError("body region must have exactly two operations");
   }