Address github issue 29071 (#29158)
This pull request addresses a regression in ONNX Runtime's graph
inlining logic, specifically ensuring that initializers with in-memory
external data (OrtValues) are correctly transferred when inlining
subgraphs (such as during constant folding of If nodes). It also adds
comprehensive regression tests and supporting test data to prevent
similar issues in the future.
The most important changes are:
**Bug Fixes and Core Logic:**
* Fixed a bug in `Graph::InlineIfSubgraph` to ensure that OrtValues for
initializers with in-memory external data are extracted from the source
graph before erasing their entries, and correctly restored in the
destination graph after inlining. This maintains the invariant that an
initializer marked as "HasExternalDataInMemory" always has a
corresponding OrtValue.
[[1]](diffhunk://#diff-e231a92b40d89409cc8e82436be0a15bc87ef95c93b303b9feaeab6e50c8835cR6067-R6077)
[[2]](diffhunk://#diff-e231a92b40d89409cc8e82436be0a15bc87ef95c93b303b9feaeab6e50c8835cL6085-R6097)
**Testing and Regression Coverage:**
* Added a regression test `InlineIfSubgraphTransfersOrtValues` to
`graph_test.cc` to verify that OrtValues are properly transferred when
inlining If subgraphs with large initializers, preventing crashes during
model saving.
* Added an end-to-end regression test
`GH_Issue_29071_HasExternalDataInMemory` to ensure that loading and
initializing a model with this pattern works as expected.
* Included the necessary import for `graph_utils.h` in the test file to
support new test logic.
**Test Data:**
* Added a Python script (`gh_issue_29071_if_constant_folding.py`) to
generate the minimal ONNX model that reproduces the original bug,
supporting ongoing regression testing.
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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
