softplus vulkan shader

[futz12]

No description provided.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.29%. Comparing base (9bd6551) to head (91bc706).
⚠️ Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6478      +/-   ##
==========================================
+ Coverage   93.23%   93.29%   +0.05%     
==========================================
  Files         852      855       +3     
  Lines      267286   266929     -357     
==========================================
- Hits       249195   249021     -174     
+ Misses      18091    17908     -183     

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[tencent-adm]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
1 out of 2 committers have signed the CLA.

✅ futz12
❌ nihui
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[Copilot]

Pull request overview

This PR adds Vulkan GPU shader support for the Softplus activation layer. The Softplus function computes log(exp(x) + 1), which is a smooth approximation of the ReLU activation function. The implementation follows the established pattern for simple activation layers in NCNN, with a header file defining the Vulkan-specific layer class, a C++ implementation file handling pipeline creation/destruction and dispatching, and a GLSL compute shader implementing the actual Softplus computation.

Changes:

• Added Vulkan layer implementation for Softplus activation (header and source)
• Added GLSL compute shader implementing the Softplus formula log(exp(v) + 1)
• Follows the established pattern for simple inplace activation layers

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
src/layer/vulkan/softplus_vulkan.h	Header file defining the Softplus_vulkan class with pipeline management and forward_inplace methods
src/layer/vulkan/softplus_vulkan.cpp	Implementation of pipeline creation, destruction, and compute dispatch logic
src/layer/vulkan/shader/softplus.comp	GLSL compute shader implementing the Softplus activation function

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[nihui]

Thanks for your contribution !