[feat](benchmark): replace load_param with load_param_mem

[0130w]

Previous implementation required benchncnn to be run from the directory containing the model files. This often caused failures and inconvenience when executed from an arbitrary working directory.​​

​This change embeds the model files directly into the executable by compiling them as C arrays. Consequently, benchncnn now becomes fully self-contained and can be run from any location without dependency on external model files.​

[github-actions]

The binary size change of libncnn.so (bytes)

architecture	base size	pr size	difference
x86_64	15046688	15046688	0 😘
armhf	6081956	6081956	0 😘
aarch64	9387400	9387400	0 😘

[tencent-adm]

All committers have signed the CLA.

[0130w]

run

cd build
cmake -DCMAKE_BUILD_TYPE=Debug -DNCNN_VULKAN=ON -DNCNN_BUILD_EXAMPLES=ON -DCMAKE_EXPORT_COMPILE_COMMANDS=ON ..
make -j$(nproc)
cd benchmark
./benchncnn 4 8 0 -1 1

result before

./benchncnn 4 8 0 -1 1
loop_count = 4
num_threads = 8
powersave = 0
gpu_device = -1
cooling_down = 1
fopen squeezenet.param failed
network graph not ready
          squeezenet  min =    0.00  max =    0.00  avg =    0.00
fopen squeezenet_int8.param failed
...

after

loop_count = 4
num_threads = 8
powersave = 0
gpu_device = -1
cooling_down = 1
          squeezenet  min =   12.68  max =   13.12  avg =   12.94
     squeezenet_int8  min =    8.39  max =    9.11  avg =    8.88
           mobilenet  min =   16.69  max =   17.01  avg =   16.83
      mobilenet_int8  min =   15.41  max =   16.59  avg =   15.86
        mobilenet_v2  min =   16.33  max =   17.03  avg =   16.67
        mobilenet_v3  min =   13.08  max =   15.00  avg =   14.34
          shufflenet  min =   10.04  max =   12.69  avg =   10.88
       shufflenet_v2  min =   10.14  max =   13.40  avg =   11.20
             mnasnet  min =   12.67  max =   16.30  avg =   14.48
     proxylessnasnet  min =   14.56  max =   16.55  avg =   15.68
     efficientnet_b0  min =   23.54  max =   25.99  avg =   24.56
   efficientnetv2_b0  min =   25.69  max =   28.93  avg =   27.90
...

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.85%. Comparing base (aad2e0c) to head (41745c8).
⚠️ Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6286      +/-   ##
==========================================
+ Coverage   95.84%   95.85%   +0.01%     
==========================================
  Files         837      837              
  Lines      264899   264848      -51     
==========================================
- Hits       253889   253877      -12     
+ Misses      11010    10971      -39     

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[Copilot]

Pull Request Overview

This PR replaces file-based model loading with memory-based loading in the benchncnn tool by embedding model parameter files directly into the executable as C arrays. This eliminates the dependency on external .param files and allows the benchmark to run from any directory.

• Introduces a CMake macro to convert .param files into C header files containing hex data arrays
• Updates benchncnn.cpp to use load_param_mem() instead of load_param() with embedded data
• Normalizes model names by replacing hyphens with underscores to ensure valid C identifiers

Reviewed Changes

Copilot reviewed 6 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
cmake/ncnn_generate_model_data_header.cmake	Adds CMake macro to convert .param files to C arrays with validation
benchmark/model_param_spv_data.h.in	Template for including generated model parameter headers
benchmark/model_param_registry.h.in	Template for model parameter registry data
benchmark/benchncnn.cpp	Updates to use embedded model data with registry lookup function
benchmark/README.md	Updates documentation to reflect new param usage without .param suffix
benchmark/CMakeLists.txt	Integrates model data generation into build process

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[Copilot]

The logic in both branches of the if-else statement is identical. Consider removing the conditional check since both fixed_path true and false cases now perform the same operations.

[Copilot]

The error message references 'model dir' which is no longer accurate since models are now embedded in memory. Consider updating to 'can't find %s model in embedded data' or similar.

Suggested change

	fprintf(stderr, "can't find %s.param in model dir\n", comment);
	fprintf(stderr, "can't find %s.param in embedded data\n", comment);