Initial commit of NonZero op (#2766)

Author: afalkenberg1

lib/Conversion/TorchOnnxToTorch/DefaultDomainGtoP.cpp

@@ -100,8 +100,7 @@ void mlir::torch::onnx_c::populateDefaultDomainGtoP(
                   rewriter.replaceOpWithNewOp<Torch::AtenLtTensorOp>(
                       binder.op, resultType, lhs, rhs);
                   return success();
-                });
-  
+                }); 
   patterns.onOp("LessOrEqual", 1,
                 [](OpBinder binder, ConversionPatternRewriter &rewriter) {
                   Torch::ValueTensorType resultType;
@@ -149,6 +148,18 @@ void mlir::torch::onnx_c::populateDefaultDomainGtoP(
 		    binder.op, resultType, lhs, rhs);
 		  return success();
 		});
+  patterns.onOp("NonZero", 13,
+    [](OpBinder binder, ConversionPatternRewriter &rewriter) {
+      Torch::ValueTensorType resultType;
+                  Value operand;
+                  if (binder.tensorOperand(operand) ||
+                      binder.tensorResultType(resultType)) {
+                    return failure();
+                  }
+                  rewriter.replaceOpWithNewOp<Torch::AtenNonzeroOp>(
+                      binder.op, resultType, operand);
+                  return success();
+                });
   patterns.onOp(
       "MaxPool", 12, [](OpBinder binder, ConversionPatternRewriter &rewriter) {
         std::string autoPad;

test/Conversion/TorchOnnxToTorch/simple_ops_g_to_p.mlir

@@ -450,6 +450,15 @@ func.func @test_not_2d(%arg0: !torch.vtensor<[3,4],i1>) -> !torch.vtensor<[3,4],
 
 // -----
 
+// CHECK-LABEL: func.func @test_nonzero
+  func.func @test_nonzero(%arg0: !torch.vtensor<[3,4,5],f32>) -> !torch.vtensor<[3,4,5],si64> attributes {torch.onnx_meta.ir_version = 7 : si64, torch.onnx_meta.opset_version = 13 : si64, torch.onnx_meta.producer_name = "backend-test", torch.onnx_meta.producer_version = ""} {
+    // CHECK: torch.aten.nonzero %arg0 : !torch.vtensor<[3,4,5],f32> -> !torch.vtensor<[3,4,5],si64>
+    %0 = torch.operator "onnx.NonZero"(%arg0) : (!torch.vtensor<[3,4,5],f32>) -> !torch.vtensor<[3,4,5],si64>
+    return %0 : !torch.vtensor<[3,4,5],si64>
+  }
+
+// -----
+
 // CHECK-LABEL: func.func @test_or2d
   func.func @test_or2d(%arg0: !torch.vtensor<[3,4],i1>, %arg1: !torch.vtensor<[3,4],i1>) -> !torch.vtensor<[3,4],i1> attributes {torch.onnx_meta.ir_version = 3 : si64, torch.onnx_meta.opset_version = 7 : si64, torch.onnx_meta.producer_name = "backend-test", torch.onnx_meta.producer_version = ""} {
     // CHECK: torch.aten.bitwise_or.Tensor %arg0, %arg1 : !torch.vtensor<[3,4],i1>, !torch.vtensor<[3,4],i1> -> !torch.vtensor<[3,4],i1>