* [Backend] Refactor Pipeline to support different backends
Introduce Pipeline abstraction in backend/pipeline.py with per-backend
registration. Each backend (cuda, hip, c, llvm) now registers its own
compilation pass pipeline. engine/lower.py resolves the pipeline from
the target instead of hardcoding phase imports.
* enhance the structure
* fuse two stage
* fix after rebase
* update template pass pipeline
* pipeline
* fix test
* fix test
* fix cuda pipeline prologue
* [Bugfix] Fix issue 2123 access_ptr lowering
Add the issue 2123 regression test and keep the access_ptr base BufferLoad intact through safe-memory legalization and lowering.
Closes#2123
* Deduplicate access_ptr base load handling
Move shared tl.access_ptr BufferLoad base visitation into a common transform helper so LowerAccessPtr and safe-memory legalization stay aligned.
Extend the issue 2123 regression with a direct LowerAccessPtr pass check while keeping the LowerAndLegalize pipeline coverage.
* Format access_ptr helper header
* Narrow access_ptr helper scope
* Share access_ptr base helper
* Address access_ptr helper review comments
* [Transform] Preserve access_ptr buffer loads in safe memory legalization
* Refactor AccessPtrInfo return structure in legalize_safe_memory_access.cc
Updated the return structure of AccessPtrInfo to improve readability and maintainability. The logic for handling the tvm_access_ptr operation has been streamlined, ensuring clearer checks and consistent formatting of returned values.
* fix
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Co-authored-by: LeiWang1999 <leiwang1999@outlook.com>