Some of the new tileop templates are added in the main branch, like pto.tci、pto.tconcat、pto.tdequant.... Should rebase the main branch and migrate those templates too.

Review: defects and risks

First, an important correction to the premise: this PR does not actually delete tilelang-dsl/. The diff contains zero changes under tilelang-dsl/ — the full directory (including the complete Python package tilelang-dsl/python/tilelang_dsl/, the daemon, tests, and examples, 64 files) still exists unchanged at the PR head. What the PR actually does:

• Deletes the 105 legacy TileLang template files (lib/TileOps/*_template.py, etc.);
• Moves the PTODSL templates from ptodsl/ptodsl/tilelib/templates/a5/ to lib/TileOps/a5/, and rewrites lib/TileOps/__init__.py as a lazy loader (all 113 module references cross-checked — none missing);
• Unwires tilelang-dsl from CMake / wheel assembly / dist-collection scripts / CI;
• Reduces the ptoas --tile-lib-backend enum to only ptodsl.

The rewiring itself is high quality: CMake, wheel assembly, dist collection, ptoas_env.sh, CI workflows, and the ptodsl tilelib import redirection are all consistently updated. I found no configure/build/package-time blockers, and the edited tests pass conceptually. However, there are the following defects and risks:

Major issues

1. Legacy backend left half-removed (risk) — lib/PTO/Transforms/ExpandTileOp.cpp:1185 still shells out to python -m tilelang_dsl.expand_helper when tile-lib-backend=tilelang, and include/PTO/Transforms/Passes.td:566-580 still defines the tilelang-path/tilelang-pkg-path options. But tools/ptoas/ptoas.cpp no longer exposes those CLI flags, and :497-498 unconditionally clears both paths. Net effect: this path is only reachable via pass-pipeline options through pto-test-opt, and it fails at runtime — unless the orphaned tilelang-dsl/python happens to be on PYTHONPATH (it only works today because that directory was not deleted). Either finish the removal in ExpandTileOp/Passes.td, or explicitly document that the legacy path is intentionally kept; the current title oversells the change.

2. tilelang-dsl/ becomes live code with no CI coverage (risk) — .github/workflows/ci_sim.yml:61 dropped tilelang-dsl/** from the path filter, yet the directory is still shell-invoked by the legacy ExpandTileOp path. Any future edit to it will trigger no CI — a silent-regression zone.

3. Stale docs now give commands that error out (minor) — ptodsl/docs/developer_guide/tilelib-debugging-playbook.md:137 still tells users to run ptoas --tile-lib-backend=tilelang, which now fails at option-parse time. Similarly, .claude/skill/pto_debug_skill.md (lines 55/590/664) and 3 skills under .codex/skills/ still teach TileLangDSL template and parity workflows, pointing at the deleted *_template.py files.

Minor issues

• Lost CI artifacts — the TileLib ST log-upload step in ci_sim.yml dropped the ${TILELIB_ST_WORKSPACE}/tilelib-st-a5/** artifact directory, yet the step still sets TILELIB_ST_OUTPUT_ROOT to write into it; per-case outputs will no longer be available when a sim fails.
• Dangling test — test/python/test_docker_runtime_packaging.py:16,38-39 still reads docker/copy_ptoas_deps.sh, which this PR deletes; running it raises FileNotFoundError. No workflow executes it today, but it should be updated/deleted in this PR.
• Stale comments — ~26 lit tests test/lit/vpto/expand_tile_op_*tilelang*.pto still comment that they expand "via the default TileLang Python DSL template lib/TileOps/tadd_template.py", a file that no longer exists.
• Dead variable PTOAS_TILEOPS_DIR — only set in ptodsl/ptoas/_runtime_entry.py:117 and asserted in its test; nothing consumes it.
• Top-level lib/ on PYTHONPATH (low risk) — _ptoas_build_backend.py:308 and scripts/ptoas_env.sh:123 add the repo's lib/ to sys.path; today only TileOps has an __init__.py, but any future lib/<dir>/__init__.py would silently become an importable top-level package.
• Naming debt (acceptable): the test/tilelang_st directory name, PTO_TILELANG_ST_* CMake variables, and the pto.tilelang.instance attribute name remain — the latter is a contract name shared by multiple C++/Python sites, so keeping it is reasonable.

Suggestions

Before merging, at minimum: delete tilelang-dsl/ and clean up the tilelang branch in ExpandTileOp/Passes.td accordingly (or retitle the PR, e.g. "Switch TileLib backend to PTODSL / unwire TilelangDSL"), fix the debugging-playbook doc, restore the tilelib-st artifact upload, and handle test_docker_runtime_packaging.py. Skills and lit comments can be follow-up cleanup.