[Mlir-commits] [mlir] [mlir][EmitC]Add a Reflection Map to a Class (PR #150572)

[Paul Kirth]

================
@@ -0,0 +1,156 @@
+//===- AddReflectionMap.cpp - Add a reflection map to a class -------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#include "mlir/Dialect/EmitC/IR/EmitC.h"
+#include "mlir/Dialect/EmitC/Transforms/Passes.h"
+#include "mlir/Dialect/EmitC/Transforms/Transforms.h"
+#include "mlir/IR/Attributes.h"
+#include "mlir/IR/Builders.h"
+#include "mlir/IR/BuiltinAttributes.h"
+#include "mlir/IR/PatternMatch.h"
+#include "mlir/Transforms/WalkPatternRewriteDriver.h"
+
+using namespace mlir;
+using namespace emitc;
+
+namespace mlir {
+namespace emitc {
+#define GEN_PASS_DEF_ADDREFLECTIONMAPPASS
+#include "mlir/Dialect/EmitC/Transforms/Passes.h.inc"
+
+namespace {
+constexpr const char *mapLibraryHeader = "map";
+constexpr const char *stringLibraryHeader = "string";
+
+IncludeOp addHeader(OpBuilder &builder, ModuleOp module, StringRef headerName) {
+  StringAttr includeAttr = builder.getStringAttr(headerName);
+  return builder.create<emitc::IncludeOp>(
+      module.getLoc(), includeAttr,
+      /*is_standard_include=*/builder.getUnitAttr());
+}
+
+class AddReflectionMapPass
+    : public impl::AddReflectionMapPassBase<AddReflectionMapPass> {
+  using AddReflectionMapPassBase::AddReflectionMapPassBase;
+  void runOnOperation() override {
+    mlir::ModuleOp module = getOperation();
+
+    RewritePatternSet patterns(&getContext());
+    populateAddReflectionMapPatterns(patterns, namedAttribute);
+
+    walkAndApplyPatterns(module, std::move(patterns));
+    bool hasMapHdr = false;
+    bool hasStringHdr = false;
+    for (auto &op : *module.getBody()) {
+      emitc::IncludeOp includeOp = llvm::dyn_cast<mlir::emitc::IncludeOp>(op);
+      if (!includeOp)
+        continue;
+      if (includeOp.getIsStandardInclude()) {
+        if (includeOp.getInclude() == mapLibraryHeader)
+          hasMapHdr = true;
+        if (includeOp.getInclude() == stringLibraryHeader)
+          hasStringHdr = true;
+      }
+      if (hasMapHdr && hasStringHdr)
+        return;
+    }
+
+    mlir::OpBuilder builder(module.getBody(), module.getBody()->begin());
+    if (!hasMapHdr) {
+      addHeader(builder, module, mapLibraryHeader);
+    }
+    if (!hasStringHdr) {
+      addHeader(builder, module, stringLibraryHeader);
+    }
+  }
+};
+
+} // namespace
+} // namespace emitc
+} // namespace mlir
+
+class AddReflectionMapClass : public OpRewritePattern<emitc::ClassOp> {
+public:
+  AddReflectionMapClass(MLIRContext *context, StringRef attrName)
+      : OpRewritePattern<emitc::ClassOp>(context), attributeName(attrName) {}
+
+  LogicalResult matchAndRewrite(mlir::emitc::ClassOp classOp,
+                                PatternRewriter &rewriter) const override {
+    MLIRContext *context = rewriter.getContext();
+
+    // Define the opaque types
+    emitc::OpaqueType mapType = mlir::emitc::OpaqueType::get(
+        context, "const std::map<std::string, char*>");
+
+    // Collect all field names
+    std::vector<std::pair<std::string, std::string>> fieldNames;
+    classOp.walk([&](mlir::emitc::FieldOp fieldOp) {
+      if (DictionaryAttr innerDictAttr = dyn_cast<mlir::DictionaryAttr>(
+              fieldOp->getAttrDictionary().get("attrs"))) {
+        ArrayAttr arrayAttr = cast<mlir::ArrayAttr>(
+            innerDictAttr.getNamed(attributeName)->getValue());
+        StringAttr stringAttr = cast<mlir::StringAttr>(arrayAttr[0]);
+        fieldNames.emplace_back(stringAttr.getValue().str(),
+                                fieldOp.getName().str());
+
+      } else {
+        fieldOp.emitError()
+            << "FieldOp must have a dictionary attribute named '"
+            << attributeName << "'"
+            << "with an array containing a string attribute";
+      }
+    });
+
+    std::stringstream ss;
+    ss << "{ ";
+    for (size_t i = 0; i < fieldNames.size(); ++i) {
+      ss << " { \"" << fieldNames[i].first << "\", reinterpret_cast<char*>(&"
+         << fieldNames[i].second << ") }";
----------------
ilovepi wrote:

Do you think this would be more readable as a `formatv()`. IMO, structures like this are harder to read when constructed via stream (e.g. its easier to misread them or miss a detail). WDYT?

https://github.com/llvm/llvm-project/pull/150572