Validate serialized prepacked buffers (#33499)
This pull request introduces a mechanism to verify the equivalence of
pre-packed weights in ONNX Runtime, ensuring that pre-packed weights
loaded from disk or shared across sessions exactly match those generated
by the current kernel. This helps prevent subtle bugs caused by
mismatched buffer contents or layouts. The main changes include
implementing an `IsEquivalentTo` method for `PrePackedWeights`, adding
validation logic to session state handling, and providing comprehensive
unit tests.
**PrePackedWeights Equivalence and Validation:**
* Added a new method `IsEquivalentTo` to the `PrePackedWeights` class to
compare buffer contents, sizes, and ownership flags for equivalence.
(`onnxruntime/core/framework/prepacked_weights.h`,
`onnxruntime/core/framework/prepacked_weights.cc`)
[[1]](diffhunk://#diff-d88f6d6584c1873f2a7596d8194b2dac02cb6ac609243f6c2ad850116c81bc75R30-R31)
[[2]](diffhunk://#diff-72fe9886d7a2247e53ed822e181677c8dbcbd0cb2765adc9ff145ae5d6987f6dR34-R56)
* Introduced a helper function `ValidatePrePackedWeights` in
`session_state.cc` that uses `IsEquivalentTo` to ensure loaded or shared
pre-packed weights match expected values, returning an error if not.
(`onnxruntime/core/framework/session_state.cc`)
**Session State Integration:**
* Integrated `ValidatePrePackedWeights` into the prepacking flow in
`SessionState::PrepackConstantInitializedTensors` to validate pre-packed
weights at all relevant points: when using shared, disk-loaded, or
cached weights. (`onnxruntime/core/framework/session_state.cc`)
[[1]](diffhunk://#diff-2126cbcd226e0e59f46b87efcb45eca3d118901a764fba01d62049b1ad0bad14R637-R638)
[[2]](diffhunk://#diff-2126cbcd226e0e59f46b87efcb45eca3d118901a764fba01d62049b1ad0bad14R669-R670)
[[3]](diffhunk://#diff-2126cbcd226e0e59f46b87efcb45eca3d118901a764fba01d62049b1ad0bad14R743-R745)
**Testing:**
* Added a comprehensive unit test
`PrePackedWeightsTest.EquivalenceRequiresMatchingLayoutAndContents` to
verify the correctness of the new equivalence logic under various
scenarios, including different buffer contents, sizes, missing buffers,
and ownership flags.
(`onnxruntime/test/framework/session_state_test.cc`)
**Build/Include Cleanups:**
* Included `<cstring>` where necessary to support buffer comparison
using `std::memcmp`. (`onnxruntime/core/framework/prepacked_weights.cc`,
`onnxruntime/test/framework/session_state_test.cc`)
[[1]](diffhunk://#diff-72fe9886d7a2247e53ed822e181677c8dbcbd0cb2765adc9ff145ae5d6987f6dR5-R7)
[[2]](diffhunk://#diff-2e498c0ec894ae05b0ddfb15f7bc4b927df6626c0497c47de85a5e808317d3f1R7)
