Taichi

Highlights:
- **Intermediate representation**
- Support SHR operator: ti.bit_shr(x, y) (1871) (by **Xuanda Yang**)
- **Miscellaneous**
- Automatic release pipeline: read semver from CMakeList directly (1885) (by **Chengchen(Rex) Wang**)
- **Refactor**
- Move statements from ir.h to statements.h (1898) (by **xumingkuan**)

Full changelog:
- [bug] Fix stable fluid BFECC advection (1764) (by **Yadi Cao**)
- [Refactor] [ir] Move statements from ir.h to statements.h (1898) (by **xumingkuan**)
- [export] Support exporting custom config variables (1893) (by **彭于斌**)
- [gui] [ipython] Add GUI.__del__ to close on variable dereference (1869) (by **彭于斌**)
- [misc] Make check previous CI run only check for Build-and-Test jobs (1899) (by **Ye Kuang**)
- [refactor] Move IRBank to a separate file (1897) (by **xumingkuan**)
- [refactor] Remove DFS in DOT generation (1896) (by **Ye Kuang**)
- [async] Optimize StateFlowGraph::optimize_listgen (1894) (by **Yuanming Hu**)
- [misc] Expose kernel statistics to python (1891) (by **Ye Kuang**)
- [async] Cache demote_activation (1889) (by **xumingkuan**)
- [async] Make optimization passes iterative (1890) (by **Ye Kuang**)
- [async] Remove ClearListStmt from possibly fused serial tasks (1888) (by **Ye Kuang**)
- [IR] [lang] Support SHR operator: ti.bit_shr(x, y) (1871) (by **Xuanda Yang**)
- [async] Classify tasks to make fusion 10.6x faster (1887) (by **xumingkuan**)
- [Misc] Automatic release pipeline: read semver from CMakeList directly (1885) (by **Chengchen(Rex) Wang**)
- [export] [cc] Support ti.RecordGroupHint to group launched kernels (1880) (by **彭于斌**)
- [async] Add element-wise info into TaskMeta for fusion (1884) (by **xumingkuan**)

Highlights:
- **Examples**
- Add mciso.py and mciso_advanced.py for marching cube (1835) (by **彭于斌**)

Full changelog:
- [cli] Setup pylint: run 'ti lint' to obtain linting results (1846) (by **彭于斌**)
- [async] More SFG optimizations (1877) (by **Yuanming Hu**)
- [Example] Add mciso.py and mciso_advanced.py for marching cube (1835) (by **彭于斌**)

Highlights:
- **Language and syntax**
- Support num_thread limitation and serial execution on CPU (1867) (by **Yuanming Hu**)

Full changelog:
- [refactor] Create class TypePromotionMapping for refactoring function promoted_type in lang_util.cpp (1874) (by **Jiafeng Liu**)
- [async] Draw nodes as record shape, allow embedding states into the nodes. (1876) (by **Ye Kuang**)
- [Lang] Support num_thread limitation and serial excution on CPU (1867) (by **Yuanming Hu**)
- [async] Cache fusion results (1875) (by **xumingkuan**)
- [Async] Fix ClearListStmt metadata (1873) (by **Yuanming Hu**)
- [async] Improve fusion optimization and add StateFlowGraph::verify (1872) (by **xumingkuan**)
- [async] Optimizations on StateFlowGraph (1870) (by **Yuanming Hu**)
- [async] Migrate AsyncEngine::fuse() to StateFlowGraph (1859) (by **xumingkuan**)
- [ir] Add ClearListStmt instead of making clear_list a unique task type (1868) (by **Ye Kuang**)
- [error] [doc] Better error message when X11 environment failed to initialize (1856) (by **彭于斌**)
- [async] Highlight user kernels in the DOT graph, allows configuring rankdir (1866) (by **Ye Kuang**)

Highlights:
- **Examples**
- Make ODOP MGPCG class in mgpcg.py generic and reuse it in stable_fluid.py (1731) (by **彭于斌**)
- **Language and syntax**
- Support ti.zero(x) and ti.one(x) for making zero/one value for the same type with x (1857) (by **彭于斌**)
- **GitHub Actions/Workflows**
- Build and test the CUDA backend using GitHub actions (1863) (by **Yuanming Hu**)

Full changelog:
- [Workflow] Build and test the CUDA backend using GitHub actions (1863) (by **Yuanming Hu**)
- [async] Patch StateFlowGraph (1862) (by **Yuanming Hu**)
- [Example] Make ODOP MGPCG class in mgpcg.py generic and reuse it in stable_fluid.py (1731) (by **彭于斌**)
- [Lang] Support ti.zero(x) and ti.one(x) for making zero/one value for the same type with x (1857) (by **彭于斌**)

Highlights:
- **Error messages**
- Raise TaichiSyntaxError when multiple return path detected (1844) (by **彭于斌**)
- **Examples**
- Physarum simulation example (1850) (by **Alexander Mordvintsev**)
- **Language and syntax**
- Support __len__ and __iter__ on ti.Matrix (1838) (by **彭于斌**)

Full changelog:
- [async] Add TaskLaunchRecord StateFlowGraph::Node::rec (1854) (by **xumingkuan**)
- [Error] Raise TaichiSyntaxError when multiple return path detected (1844) (by **彭于斌**)
- [async] Fix missing edges and nodes in SFG (1853) (by **Yuanming Hu**)
- [pypi] Remove setuptools from hard dependencies (1845) (by **彭于斌**)
- [Example] Physarum simulation example (1850) (by **Alexander Mordvintsev**)
- [workflow] Update issue templates (1794) (by **彭于斌**)
- [async] Generate DOT graph for StateFlowGraph (1852) (by **Ye Kuang**)
- [async] Implement IRBank and IRHandle (1839) (by **xumingkuan**)
- [misc] Fix check previous run by using GITHUB_TOKEN to authenticate APIs (1849) (by **Ye Kuang**)
- [cuda] Fix CUDA driver API signature (1834) (by **Yuanming Hu**)
- [async] Improve StateFlowGraph (1843) (by **Yuanming Hu**)
- [ir] Remove the usage of kernel from type_check() pass (1848) (by **Ye Kuang**)
- [misc] Check the previous Github workflow run status if CI is skipped (1837) (by **Ye Kuang**)
- [Lang] Support __len__ and __iter__ on ti.Matrix (1838) (by **彭于斌**)

Highlights:
- **Documentation**
- Doc the workflow for exporting Taichi kernels to C99 source (1756) (by **彭于斌**)
- Add performance.rst introducing the 'ti.block_dim' API (1691) (by **彭于斌**)
- Add document for XYZW accessors of vector (1797) (by **彭于斌**)
- **GUI**
- Support saving image without GUI showing a window (1817) (by **thinking-tower**)
- **Refactor**
- Refactor Block::parent from Block* to Stmt* (1815) (by **xumingkuan**)

Full changelog:
- [refactor] Use promise/future to retrieve the function compiled asynchronously (1831) (by **Ye Kuang**)
- [GUI] Support saving image without GUI showing a window (1817) (by **thinking-tower**)
- [ir] [bug] Fix demote_operations lacking type_check (1825) (by **彭于斌**)
- [refactor] Rename KernelLaunchRecord to TaskLaunchRecord (1828) (by **Ye Kuang**)
- [Doc] [cc] Doc the workflow for exporting Taichi kernels to C99 source (1756) (by **彭于斌**)
- [Doc] Add performance.rst introducing the 'ti.block_dim' API (1691) (by **彭于斌**)
- [Doc] Add document for XYZW accessors of vector (1797) (by **彭于斌**)
- [ir] [bug] Demote all local atomic operations, not only add (1819) (by **彭于斌**)
- [doc] Document data structure organization (995) (by **Yuanming Hu**)
- [ir] [refactor] Reorder FrontAssertStatement's constructor args (1822) (by **Ye Kuang**)
- [Refactor] [ir] Refactor Block::parent from Block* to Stmt* (1815) (by **xumingkuan**)
- [refactor] Rename 'launched_kernels*' stats to 'launched_tasks*' (1821) (by **Ye Kuang**)