discover VK_EXT_external_memory_host, vkhostallocator and use_weights_in_host_memory option

[nihui]

No description provided.

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 6.69145% with 251 lines in your changes missing coverage. Please review.
✅ Project coverage is 92.95%. Comparing base (4ea7bfc) to head (93a5fef).

Files with missing lines	Patch %	Lines
src/allocator.cpp	0.00%	248 Missing ⚠️
src/gpu.cpp	88.23%	2 Missing ⚠️
src/net.cpp	66.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6531      +/-   ##
==========================================
- Coverage   93.04%   92.95%   -0.10%     
==========================================
  Files         809      809              
  Lines      256244   256458     +214     
==========================================
- Hits       238430   238394      -36     
- Misses      17814    18064     +250     

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[Copilot]

Pull request overview

This PR adds support for the Vulkan extension VK_EXT_external_memory_host, introduces a new VkHostAllocator class that can import host-allocated memory into Vulkan device memory, and adds a new option use_weights_in_host_memory to control whether to use this allocator for weight storage.

Changes:

• Added Vulkan extension definition for VK_EXT_external_memory_host in header fix file
• Renamed reserved option field to use_weights_in_host_memory to enable host memory usage for weights
• Implemented VkHostAllocator that uses external memory import when the extension is available

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
src/vulkan_header_fix.h	Adds structures and constants for VK_EXT_external_memory_host extension
src/option.h	Renames use_reserved_2 to use_weights_in_host_memory
src/option.cpp	Initializes use_weights_in_host_memory to false
src/net.cpp	Uses VkHostAllocator when use_weights_in_host_memory is enabled
src/gpu.h	Adds support query and function pointer for VK_EXT_external_memory_host
src/gpu.cpp	Implements extension detection and initialization for VK_EXT_external_memory_host
src/allocator.h	Declares VkHostAllocator class and allocate_import_host_memory method
src/allocator.cpp	Implements VkHostAllocator with external host memory import support and fixes Android Hardware Buffer mapped_ptr initialization

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[Copilot]

Pull request overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 4 comments.

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