add relu lowering

add relu validation
add spatial compute helper
minor refactors

src/PIM/Conversion/ONNXToSpatial/Patterns/NN/Relu.cpp

@@ -0,0 +1,33 @@
+#include "mlir/Transforms/DialectConversion.h"
+
+#include "src/Accelerators/PIM/Conversion/ONNXToSpatial/Common.hpp"
+#include "src/Accelerators/PIM/Dialect/Spatial/SpatialOps.hpp"
+#include "src/Dialect/ONNX/ONNXOps.hpp"
+
+using namespace mlir;
+
+namespace onnx_mlir {
+namespace {
+
+struct ReluToSpatialCompute : OpConversionPattern<ONNXReluOp> {
+  using OpConversionPattern::OpConversionPattern;
+
+  LogicalResult
+  matchAndRewrite(ONNXReluOp reluOp, ONNXReluOpAdaptor adaptor, ConversionPatternRewriter& rewriter) const override {
+    Location loc = reluOp.getLoc();
+    Type resultType = reluOp.getResult().getType();
+    constexpr size_t numInputs = 1;
+    auto computeOp = createSpatCompute<numInputs>(rewriter, loc, resultType, {}, adaptor.getX(), [&](Value x) {
+      auto spatReluOp = spatial::SpatReluOp::create(rewriter, loc, resultType, x);
+      spatial::SpatYieldOp::create(rewriter, loc, spatReluOp.getResult());
+    });
+    rewriter.replaceOp(reluOp, computeOp);
+    return success();
+  }
+};
+
+} // namespace
+
+void populateReluPatterns(RewritePatternSet& patterns, MLIRContext* ctx) { patterns.add<ReluToSpatialCompute>(ctx); }
+
+} // namespace onnx_mlir