✨ Add QIRSetAttributesAndMetadata Pass (#1787)

Author: MatthiasReumann

CHANGELOG.md

@@ -42,7 +42,7 @@ with the exception that minor releases may include breaking changes.
   [#1569], [#1570], [#1572], [#1573], [#1580], [#1602], [#1620], [#1623],
   [#1624], [#1626], [#1627], [#1635], [#1638], [#1673], [#1675], [#1700],
   [#1710], [#1717], [#1728], [#1730], [#1749], [#1751], [#1762], [#1765],
-  [#1774], [#1781], [#1782])
+  [#1774], [#1781], [#1782], [#1787])
   ([**@burgholzer**], [**@denialhaag**], [**@taminob**], [**@DRovara**],
   [**@li-mingbao**], [**@Ectras**], [**@MatthiasReumann**],
   [**@simon1hofmann**])
@@ -598,6 +598,7 @@ changelogs._
 
 <!-- PR links -->
 
+[#1787]: https://github.com/munich-quantum-toolkit/core/pull/1787
 [#1782]: https://github.com/munich-quantum-toolkit/core/pull/1782
 [#1781]: https://github.com/munich-quantum-toolkit/core/pull/1781
 [#1776]: https://github.com/munich-quantum-toolkit/core/pull/1776

mlir/include/mlir/Conversion/QCToQIR/QIRCommon/QIRCommon.h

@@ -10,8 +10,6 @@
 
 #pragma once
 
-#include "mlir/Dialect/QIR/Utils/QIRMetadata.h"
-
 #include <llvm/ADT/StringMap.h>
 #include <llvm/Support/Allocator.h>
 #include <llvm/Support/StringSaver.h>
@@ -26,7 +24,6 @@
 #include <utility>
 
 namespace mlir {
-using namespace qir;
 
 /** @brief Qubit allocation mode */
 enum class AllocationMode : std::uint8_t {
@@ -38,7 +35,7 @@ enum class AllocationMode : std::uint8_t {
 /**
  * @brief State object for tracking lowering information during QIR conversion
  */
-struct LoweringState : QIRMetadata {
+struct LoweringState {
   /// Cache static qubit pointers for reuse
   DenseMap<int64_t, Value> staticQubits;
 

mlir/include/mlir/Dialect/QIR/Builder/QIRProgramBuilder.h

@@ -10,8 +10,6 @@
 
 #pragma once
 
-#include "mlir/Dialect/QIR/Utils/QIRMetadata.h"
-
 #include <llvm/ADT/StringMap.h>
 #include <llvm/Support/Allocator.h>
 #include <llvm/Support/StringSaver.h>
@@ -1086,15 +1084,18 @@ class QIRProgramBuilder final : public ImplicitLocOpBuilder {
   /// Map from register to their loaded indices
   DenseMap<Value, DenseSet<Value>> loadedQubits;
 
-  /// Track qubit and result counts for QIR metadata
-  QIRMetadata metadata_;
-
   /// Helper variable for storing the LLVM pointer type
   Type ptrType;
 
   /// Helper variable for storing the LLVM void type
   Type voidType;
 
+  /// The number of used qubits.
+  size_t numQubits{0};
+
+  /// The number of result values.
+  size_t numResults{0};
+
   /**
    * @brief Helper to create a LLVM CallOp
    *

mlir/include/mlir/Dialect/QIR/Transforms/Passes.td

@@ -11,6 +11,15 @@
 
 include "mlir/Pass/PassBase.td"
 
+def QIRSetAttributesAndMetadata
+    : Pass<"set-qir-attributes-and-metadata", "mlir::ModuleOp"> {
+  let dependentDialects = ["mlir::LLVM::LLVMDialect"];
+  let summary = "Sets the required attributes to the entry point function and "
+                "adds the required module flags, compliant with QIR 2.1";
+  let options = [Option<"useAdaptive", "use-adaptive", "bool",
+                        /*default= */ "true", "Specifies the profile.">];
+}
+
 def QIRCleanupPass : Pass<"qir-cleanup", "mlir::ModuleOp"> {
   let dependentDialects = ["mlir::LLVM::LLVMDialect"];
   let summary = "Remove redundant QIR runtime bookkeeping.";

mlir/include/mlir/Dialect/QIR/Utils/QIRMetadata.h

@@ -10,8 +10,6 @@
 
 #pragma once
 
-#include "mlir/Dialect/QIR/Utils/QIRMetadata.h"
-
 #include <llvm/Support/ErrorHandling.h>
 #include <mlir/IR/Location.h>
 #include <mlir/IR/Types.h>
@@ -169,29 +167,6 @@ DEFINE_GETTER(XXMINUSYY)
  */
 LLVM::LLVMFuncOp getMainFunction(Operation* op);
 
-/**
- * @brief Set QIR base profile metadata attributes on the main function
- *
- * @details
- * Adds the required metadata attributes for QIR base profile compliance:
- * - `entry_point`: Marks the main entry point function
- * - `output_labeling_schema`: labeled
- * - `qir_profiles`: base_profile
- * - `required_num_qubits`: Number of qubits used
- * - `required_num_results`: Number of measurement results
- * - `qir_major_version`: 2
- * - `qir_minor_version`: 1
- * - `dynamic_qubit_management`: true/false
- * - `dynamic_result_management`: true/false
- *
- * These attributes are required by the QIR specification and inform QIR
- * consumers about the module's resource requirements and capabilities.
- *
- * @param main The main LLVM function to annotate
- * @param metadata The QIR metadata containing qubit/result counts
- */
-void setQIRAttributes(LLVM::LLVMFuncOp& main, const QIRMetadata& metadata);
-
 /**
  * @brief Get or create a QIR function declaration
  *

mlir/include/mlir/Dialect/QIR/Utils/QIRUtils.h

@@ -17,6 +17,14 @@ class ModuleOp;
 class PassManager;
 } // namespace mlir
 
+/**
+ * @brief Populate the pass manager and run it on the module.
+ */
+mlir::LogicalResult
+runWithPassManager(mlir::ModuleOp module,
+                   mlir::function_ref<void(mlir::PassManager&)> populatePasses,
+                   mlir::StringRef errorMessage);
+
 /**
  * @brief Populate a QC-oriented cleanup pipeline on the given pass manager.
  * @details Adds generic cleanup and QC qubit-register shrinking.
@@ -31,9 +39,10 @@ void populateQCOCleanupPipeline(mlir::PassManager& pm);
 
 /**
  * @brief Populate a QIR-oriented cleanup pipeline on the given pass manager.
- * @details Adds generic cleanup and QIR-specific simplifications.
+ * @details Adds generic cleanup and QIR-specific simplifications. Updates the
+ * meta data accordingly.
  */
-void populateQIRCleanupPipeline(mlir::PassManager& pm);
+void populateQIRCleanupPipeline(mlir::PassManager& pm, bool useAdaptive);
 
 /**
  * @brief Run the QC-oriented cleanup pipeline on a module.
@@ -48,4 +57,5 @@ void populateQIRCleanupPipeline(mlir::PassManager& pm);
 /**
  * @brief Run the QIR-oriented cleanup pipeline on a module.
  */
-[[nodiscard]] mlir::LogicalResult runQIRCleanupPipeline(mlir::ModuleOp module);
+[[nodiscard]] mlir::LogicalResult runQIRCleanupPipeline(mlir::ModuleOp module,
+                                                        bool useAdaptive);

mlir/include/mlir/Support/Passes.h

@@ -19,8 +19,8 @@ add_mlir_library(
   MLIRTransformUtils
   MLIRQCToQCO
   MLIRQCOToQC
-  MLIRQCToQIRAdaptive
   MLIRQCToQIRBase
+  MLIRQCToQIRAdaptive
   MLIRQCOTransforms
   MQT::MLIRSupport)
 

mlir/lib/Compiler/CMakeLists.txt

@@ -199,18 +199,15 @@ QuantumCompilerPipeline::runPipeline(ModuleOp module,
   }
   // Stage 9: QC-to-QIR conversion (optional)
   if (convertToQIR) {
-    auto addConversionPass = [&](PassManager& pm) {
-      if (config_.convertToQIRBase) {
-        pm.addPass(createQCToQIRBase());
-      } else {
-        pm.addPass(createQCToQIRAdaptive());
-      }
-    };
-
-    if (failed(runStage(addConversionPass))) {
+    if (failed(runStage([&](PassManager& pm) {
+          if (config_.convertToQIRAdaptive) {
+            pm.addPass(createQCToQIRAdaptive());
+          } else {
+            pm.addPass(createQCToQIRBase());
+          }
+        }))) {
       return failure();
     }
-
     if (record != nullptr && config_.recordIntermediates) {
       record->afterQIRConversion = captureIR(module);
       if (config_.printIRAfterAllStages) {
@@ -219,8 +216,9 @@ QuantumCompilerPipeline::runPipeline(ModuleOp module,
       }
     }
     // Stage 10: QIR cleanup (optional)
-    if (failed(runStage(
-            [&](PassManager& pm) { populateQIRCleanupPipeline(pm); }))) {
+    if (failed(runStage([&](PassManager& pm) {
+          populateQIRCleanupPipeline(pm, config_.convertToQIRAdaptive);
+        }))) {
       return failure();
     }
     if (record != nullptr && config_.recordIntermediates) {

mlir/lib/Compiler/CompilerPipeline.cpp

@@ -35,7 +35,6 @@
 #include <mlir/IR/Region.h>
 #include <mlir/Pass/PassManager.h>
 #include <mlir/Support/LogicalResult.h>
-#include <mlir/Support/WalkResult.h>
 #include <mlir/Transforms/DialectConversion.h>
 
 #include <cassert>
@@ -84,9 +83,6 @@ struct ConvertMemRefAllocOp final
     }
 
     auto& state = getState();
-    state.useDynamicQubit = true;
-    state.useArrays = true;
-
     auto* ctx = getContext();
     auto ptrType = LLVM::LLVMPointerType::get(ctx);
 
@@ -235,7 +231,6 @@ struct ConvertQCAllocOp final : StatefulOpConversionPattern<AllocOp> {
                                           op.getOperation()))) {
       return failure();
     }
-    state.useDynamicQubit = true;
 
     auto* ctx = getContext();
     auto ptrType = LLVM::LLVMPointerType::get(ctx);
@@ -363,8 +358,6 @@ struct ConvertQCMeasureOp final : StatefulOpConversionPattern<MeasureOp> {
   matchAndRewrite(MeasureOp op, OpAdaptor adaptor,
                   ConversionPatternRewriter& rewriter) const override {
     auto& state = getState();
-    state.useDynamicResult = true;
-
     auto& resultArrays = state.resultArrays;
     auto& loadedResults = state.loadedResults;
     auto& resultPtrs = state.resultPtrs;
@@ -381,7 +374,6 @@ struct ConvertQCMeasureOp final : StatefulOpConversionPattern<MeasureOp> {
     // Get result pointer
     Value result;
     if (op.getRegisterName() && op.getRegisterSize() && op.getRegisterIndex()) {
-      state.useArrays = true;
       const auto registerName = op.getRegisterName().value();
       const auto registerSize =
           static_cast<int64_t>(op.getRegisterSize().value());
@@ -425,7 +417,6 @@ struct ConvertQCMeasureOp final : StatefulOpConversionPattern<MeasureOp> {
       rewriter.setInsertionPoint(state.entryBlock->getTerminator());
       result = createPointerFromIndex(rewriter, op.getLoc(), resultPtrs.size());
       resultPtrs.try_emplace(resultPtrs.size(), result);
-      state.numResults++;
     }
 
     rewriter.restoreInsertionPoint(savedInsertionPoint);
@@ -573,22 +564,6 @@ struct QCToQIRAdaptive final : impl::QCToQIRAdaptiveBase<QCToQIRAdaptive> {
     }
   }
 
-  /**
-   * @brief Iterates through the module to find any scf.while or scf.for
-   * operation to set the backward branching flag before they are converted to
-   * cf operations.
-   */
-  static void setSCFFlags(Operation* op, LoweringState* state) {
-    op->walk([&](scf::ForOp) {
-      state->backwardsBranching += 1;
-      return WalkResult::interrupt();
-    });
-    op->walk([&](scf::WhileOp) {
-      state->backwardsBranching += 2;
-      return WalkResult::interrupt();
-    });
-  }
-
 protected:
   /**
    * @brief Executes the QC to QIR conversion pass
@@ -614,15 +589,11 @@ struct QCToQIRAdaptive final : impl::QCToQIRAdaptiveBase<QCToQIRAdaptive> {
    * Convert QC dialect operations and memref operations to QIR calls and add
    * output recording to the output block.
    *
-   * **Stage 6: QIR Attributes**
-   * Add QIR Profile metadata to the main function, including qubit/result
-   * counts and version information.
-   *
-   * **Stage 7: Standard dialects to LLVM**
+   * **Stage 6: Standard dialects to LLVM**
    * Convert arith and control flow dialects to LLVM (for index arithmetic and
    * function control flow).
    *
-   * **Stage 8: Reconcile casts**
+   * **Stage 7: Reconcile casts**
    * Clean up any unrealized cast operations introduced during type
    * conversion.
    */
@@ -632,15 +603,11 @@ struct QCToQIRAdaptive final : impl::QCToQIRAdaptiveBase<QCToQIRAdaptive> {
     ConversionTarget target(*ctx);
     QCToQIRTypeConverter typeConverter(ctx);
     LoweringState state;
-    state.useAdaptive = true;
 
     target.addLegalDialect<LLVM::LLVMDialect>();
 
     // Stage 1: Convert scf dialect to cf
     {
-      // Find the required flags before the scf operations are converted
-      setSCFFlags(moduleOp, &state);
-
       RewritePatternSet scfPatterns(ctx);
       target.addIllegalDialect<scf::SCFDialect>();
       target.addLegalDialect<cf::ControlFlowDialect>();
@@ -696,10 +663,7 @@ struct QCToQIRAdaptive final : impl::QCToQIRAdaptiveBase<QCToQIRAdaptive> {
       releaseResults(main, ctx, &state);
     }
 
-    // Stage 6: Set QIR metadata attributes
-    setQIRAttributes(main, state);
-
-    // Stage 7: Convert standard dialects to LLVM
+    // Stage 6: Convert standard dialects to LLVM
     {
       RewritePatternSet stdPatterns(ctx);
       target.addIllegalDialect<arith::ArithDialect>();
@@ -716,7 +680,7 @@ struct QCToQIRAdaptive final : impl::QCToQIRAdaptiveBase<QCToQIRAdaptive> {
       }
     }
 
-    // Stage 8: Reconcile unrealized casts
+    // Stage 7: Reconcile unrealized casts
     PassManager passManager(ctx);
     passManager.addPass(createReconcileUnrealizedCastsPass());
     if (passManager.run(moduleOp).failed()) {