mips msa optimization for cast fp16 (#3927)

src/layer/mips/cast_mips.cpp

@@ -0,0 +1,209 @@
+// Tencent is pleased to support the open source community by making ncnn available.
+//
+// Copyright (C) 2022 THL A29 Limited, a Tencent company. All rights reserved.
+//
+// Licensed under the BSD 3-Clause License (the "License"); you may not use this file except
+// in compliance with the License. You may obtain a copy of the License at
+//
+// https://opensource.org/licenses/BSD-3-Clause
+//
+// Unless required by applicable law or agreed to in writing, software distributed
+// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+// CONDITIONS OF ANY KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations under the License.
+
+#include "cast_mips.h"
+
+#if __mips_msa
+#include <msa.h>
+#endif // __mips_msa
+
+namespace ncnn {
+
+Cast_mips::Cast_mips()
+{
+    support_packing = true;
+}
+
+int Cast_mips::forward(const Mat& bottom_blob, Mat& top_blob, const Option& opt) const
+{
+    if (type_from == type_to)
+    {
+        top_blob = bottom_blob;
+        return 0;
+    }
+
+    int w = bottom_blob.w;
+    int h = bottom_blob.h;
+    int d = bottom_blob.d;
+    int channels = bottom_blob.c;
+    int dims = bottom_blob.dims;
+    size_t elemsize = bottom_blob.elemsize;
+    int elempack = bottom_blob.elempack;
+
+    size_t out_elemsize = elemsize;
+    if (type_to == 1)
+    {
+        if (type_from == 3)
+        {
+            Cast::forward(bottom_blob, top_blob, opt);
+        }
+
+        // float32
+        out_elemsize = 4 * elempack;
+    }
+    else if (type_to == 2)
+    {
+        // float16
+        out_elemsize = 2 * elempack;
+    }
+    else if (type_to == 3)
+    {
+        // int8
+        out_elemsize = elempack;
+    }
+    else if (type_to == 4)
+    {
+        // bfloat16
+        out_elemsize = 2 * elempack;
+    }
+
+    if (dims == 1)
+    {
+        top_blob.create(w, out_elemsize, elempack, opt.blob_allocator);
+    }
+    else if (dims == 2)
+    {
+        top_blob.create(w, h, out_elemsize, elempack, opt.blob_allocator);
+    }
+    else if (dims == 3)
+    {
+        top_blob.create(w, h, channels, out_elemsize, elempack, opt.blob_allocator);
+    }
+    else if (dims == 4)
+    {
+        top_blob.create(w, h, d, channels, out_elemsize, elempack, opt.blob_allocator);
+    }
+    if (top_blob.empty())
+        return -100;
+
+    int size = w * h * d * elempack;
+
+    if (type_from == 1 && type_to == 2)
+    {
+        #pragma omp parallel for num_threads(opt.num_threads)
+        for (int q = 0; q < channels; q++)
+        {
+            const float* ptr = bottom_blob.channel(q);
+            unsigned short* outptr = top_blob.channel(q);
+
+            int i = 0;
+#if __mips_msa
+            for (; i + 7 < size; i += 8)
+            {
+                __builtin_prefetch(ptr + 16);
+                v4f32 _p0 = (v4f32)__msa_ld_w(ptr, 0);
+                v4f32 _p1 = (v4f32)__msa_ld_w(ptr + 4, 0);
+                v8i16 _p = __msa_fexdo_h(_p1, _p0);
+                __msa_st_h(_p, outptr, 0);
+
+                ptr += 8;
+                outptr += 8;
+            }
+#endif // __mips_msa
+            for (; i < size; i++)
+            {
+                *outptr = float32_to_float16(*ptr);
+                outptr++;
+                ptr++;
+            }
+        }
+    }
+
+    if (type_from == 2 && type_to == 1)
+    {
+        #pragma omp parallel for num_threads(opt.num_threads)
+        for (int q = 0; q < channels; q++)
+        {
+            const unsigned short* ptr = bottom_blob.channel(q);
+            float* outptr = top_blob.channel(q);
+
+            int i = 0;
+#if __mips_msa
+            for (; i + 7 < size; i += 8)
+            {
+                __builtin_prefetch(ptr + 16);
+                v8i16 _p = __msa_ld_h(ptr, 0);
+                v4f32 _p0 = __msa_fexupr_w(_p);
+                v4f32 _p1 = __msa_fexupl_w(_p);
+                __msa_st_w((v4i32)_p0, outptr, 0);
+                __msa_st_w((v4i32)_p1, outptr + 4, 0);
+
+                ptr += 8;
+                outptr += 8;
+            }
+#endif // __mips_msa
+            for (; i < size; i++)
+            {
+                *outptr = float16_to_float32(*ptr);
+                outptr++;
+                ptr++;
+            }
+        }
+    }
+
+    if (type_from == 3 && type_to == 1)
+    {
+        #pragma omp parallel for num_threads(opt.num_threads)
+        for (int q = 0; q < channels; q++)
+        {
+            const signed char* ptr = bottom_blob.channel(q);
+            float* outptr = top_blob.channel(q);
+
+            for (int i = 0; i < size; i++)
+            {
+                outptr[i] = (float)ptr[i];
+            }
+        }
+    }
+
+    if (type_from == 4 && type_to == 1)
+    {
+        #pragma omp parallel for num_threads(opt.num_threads)
+        for (int q = 0; q < channels; q++)
+        {
+            const unsigned short* ptr = bottom_blob.channel(q);
+            float* outptr = top_blob.channel(q);
+
+            int i = 0;
+            for (; i < size; i++)
+            {
+                *outptr = bfloat16_to_float32(*ptr);
+                outptr++;
+                ptr++;
+            }
+        }
+    }
+
+    if (type_from == 1 && type_to == 4)
+    {
+        #pragma omp parallel for num_threads(opt.num_threads)
+        for (int q = 0; q < channels; q++)
+        {
+            const float* ptr = bottom_blob.channel(q);
+            unsigned short* outptr = top_blob.channel(q);
+
+            int i = 0;
+            for (; i < size; i++)
+            {
+                *outptr = float32_to_bfloat16(*ptr);
+                outptr++;
+                ptr++;
+            }
+        }
+    }
+
+    return 0;
+}
+
+} // namespace ncnn

src/layer/mips/cast_mips.h

@@ -0,0 +1,32 @@
+// Tencent is pleased to support the open source community by making ncnn available.
+//
+// Copyright (C) 2022 THL A29 Limited, a Tencent company. All rights reserved.
+//
+// Licensed under the BSD 3-Clause License (the "License"); you may not use this file except
+// in compliance with the License. You may obtain a copy of the License at
+//
+// https://opensource.org/licenses/BSD-3-Clause
+//
+// Unless required by applicable law or agreed to in writing, software distributed
+// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+// CONDITIONS OF ANY KIND, either express or implied. See the License for the
+// specific language governing permissions and limitations under the License.
+
+#ifndef LAYER_CAST_MIPS_H
+#define LAYER_CAST_MIPS_H
+
+#include "cast.h"
+
+namespace ncnn {
+
+class Cast_mips : virtual public Cast
+{
+public:
+    Cast_mips();
+
+    virtual int forward(const Mat& bottom_blob, Mat& top_blob, const Option& opt) const;
+};
+
+} // namespace ncnn
+
+#endif // LAYER_CAST_MIPS_H