chore: import upstream snapshot with attribution

2026-07-13 13:33:03 +08:00
commit 5b57521aa1
8226 changed files with 3425766 additions and 0 deletions
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+//
+//  GatherGrad.cpp
+//  MNN
+//
+//  Created by MNN on 2021/02/20.
+//  Copyright © 2018, Alibaba Group Holding Limited
+//
+
+#include "OpGrad.hpp"
+using namespace std;
+namespace MNN {
+using namespace MNN::Express;
+
+class GatherGrad : public OpGrad {
+public:
+    virtual std::vector<Express::VARP> onGrad(Express::EXPRP expr,
+                                              const std::vector<Express::VARP>& backwardOutput) override {
+        auto op = expr->get();
+        const auto& inputs = expr->inputs();
+        auto param = inputs[0];
+        auto indice = inputs[1];
+        auto dims = indice->getInfo()->dim;
+        dims.emplace_back(1);
+        indice = _Reshape(indice, dims);
+        int axis = 0;
+        std::vector<VARP> res(inputs.size());
+        if (inputs.size() > 2) {
+            axis = inputs[2]->readMap<int>()[0];
+        }
+        if (axis != 0) {
+            MNN_ERROR("Current's don't support axis != 0 grad for gather\n");
+            return res;
+        }
+        auto shape = _Shape(param);
+        auto diff = _Unsqueeze(backwardOutput[0], {axis});
+        res[0] = _ScatterNd(indice, diff, shape);
+        return res;
+    }
+};
+
+static void _create() {
+    static GatherGrad _c;
+    OpGrad::insert((int)OpType_GatherV2, &_c);
+
+}
+
+REGISTER_GRAD(GatherGrad_cpp, _create);
+};
+