Taichi

Highlights:
- **Documentation**
- Improve Taichi kernels and functions definition (1576) (by **彭于斌**)
- **Examples**
- Add mpm3d.py for dimension-independent MPM method (1639) (by **彭于斌**)
- **IPython and other shells**
- Use 'sourceinspect' to support Blender scripting module and IDLE shell (1664) (by **彭于斌**)

Full changelog:
- [Example] Add mpm3d.py for dimension-independent MPM method (1639) (by **彭于斌**)
- [misc] Prevent 'supported_archs()' invocation in 'adaptive_arch_select()' for better compatibility (1666) (by **彭于斌**)
- [test] Replace ti.var by ti.field in tests starting with h-q (1683) (by **Xudong Feng**)
- [test] Replace ti.var by ti.field in tests starting with a-g (1681) (by **Xudong Feng**)
- Turn on the CC backend in the Dockerfile (1680) (by **samuela**)
- [llvm] Obsolete LLVM 8 support (1685) (by **Yuanming Hu**)
- [Doc] [refactor] Improve Taichi kernels and functions definition (1576) (by **彭于斌**)
- [cli] Add 'ti diagnose' command for providing system informations (1671) (by **彭于斌**)
- [cc] Add ti.cfg.cc_compile_cmd and ti.cfg.cc_link_cmd (1645) (by **彭于斌**)
- [IPython] Use 'sourceinspect' to support Blender scripting module and IDLE shell (1664) (by **彭于斌**)
- [misc] Add links to the mirror repo in Gitee (1665) (by **彭于斌**)
- [misc] Update doc version (1672) (by **Yuanming Hu**)
- [misc] [refactor] Add fully_deprecated mark for future use (1656) (by **彭于斌**)
- [doc] Fix uncovered while deprecated term 'tensor' occurance (1653) (by **彭于斌**)

Highlights:
- **Bug fixes**
- Fix random side-effect causing SSA violation in ti.Vector (1631) (by **彭于斌**)
- **Documentation**
- Replace fields of xxx by xxx field (1599) (by **Xudong Feng**)
- Replace "tensor" by "field" in documentation (1633) (by **Xudong Feng**)
- Improve type.rst readability (1618) (by **彭于斌**)
- **Examples**
- Add cg_possion.py, a Poisson solver based on conjugate gradients (1595) (by **彭于斌**)
- Enhance stable_fluid.py with BFECC, RK2, RK3 and Taichi's new syntax (1617) (by **彭于斌**)
- **GUI**
- Support gui.fps_limit and reduce idle power consumption (1611) (by **彭于斌**)
- Support images with 2 channels (RG) in GUI.set_image (1624) (by **彭于斌**)
- Support gui.arrow() and gui.arrows() (1625) (by **彭于斌**)
- **Language and syntax**
- Support float and int as aliases for default-precision data types (1585) (by **彭于斌**)
- **Miscellaneous**
- Catch RuntimeError when detecting backends for better compatibility (1647) (by **彭于斌**)
- **IR optimization passes**
- Improve aliasing analysis for SNodes with trailing bits (1657) (by **xumingkuan**)
- Improve the binary ops simplify pass (1646) (by **xumingkuan**)
- **Refactor**
- "x.snode()" is deprecated, use "x.snode" instead (1654) (by **彭于斌**)

Full changelog:
- [bug] [sparse] Fix struct-fors on pointer SNodes (1662) (by **Yuanming Hu**)
- [misc] [linux] Further improve misc/linker.map to prevent Blender segementation fault (1661) (by **彭于斌**)
- [doc] Re-update documentation on autodiff (1623) (by **彭于斌**)
- [Opt] Improve aliasing analysis for SNodes with trailing bits (1657) (by **xumingkuan**)
- `bgcolor` -> `background_color` in GUI docs (1660) (by **samuela**)
- [Misc] [bug] Catch RuntimeError when detecting backends for better compatibility (1647) (by **彭于斌**)
- [workflow] Add Mac OS X to Github CI (1649) (by **彭于斌**)
- [Example] Add cg_possion.py, a Poisson solver based on conjugate gradients (1595) (by **彭于斌**)
- [Refactor] "x.snode()" is deprecated, use "x.snode" instead (1654) (by **彭于斌**)
- [GUI] Support gui.fps_limit and reduce idle power consumption (1611) (by **彭于斌**)
- [GUI] Support images with 2 channels (RG) in GUI.set_image (1624) (by **彭于斌**)
- [Opt] Improve the binary ops simplify pass (1646) (by **xumingkuan**)
- [benchmark] Fix test_test.py benchmark including '<lambda>' in filename (1650) (by **彭于斌**)
- [cc] [workflow] Add C backend to Github CI (1643) (by **彭于斌**)
- [Doc] Replace fields of xxx by xxx field (1599) (by **Xudong Feng**)
- [cc] Compose ActionRecorder outputs into a single C file for Emscripten (1629) (by **彭于斌**)
- [error] Better error messages when using wrong type annotations (1612) (by **彭于斌**)
- [doc] Update instructions for using Stop Motion OBJ with PLY sequences (1638) (by **Justin**)
- [Doc] Replace "tensor" by "field" in documentation (1633) (by **Xudong Feng**)
- [doc] Fix typo in faq.rst (1636) (by **Danni**)
- Fix hyperlink in faq.rst (1637) (by **Danni**)
- [Example] Enhance stable_fluid.py with BFECC, RK2, RK3 and Taichi's new syntax (1617) (by **彭于斌**)
- [GUI] Support gui.arrow() and gui.arrows() (1625) (by **彭于斌**)
- [Lang] Support float and int as aliases for default-precision data types (1585) (by **彭于斌**)
- [Bug] Fix random side-effect causing SSA violation in ti.Vector (1631) (by **彭于斌**)
- [infra] Support GCC as compiler for Taichi developers (experimental) (1598) (by **彭于斌**)
- [Doc] Improve type.rst readability (1618) (by **彭于斌**)
- [gui] [bug] Fix hex_to_rgb (1630) (by **Yuanming Hu**)
- [async] Clone offloaded tasks lazily by maintaining a cached template task (1619) (by **Ye Kuang**)

Highlights:
- **Bug fixes**
- Fix compiler error when flattening if(0) and if(1) (1613) (by **xumingkuan**)
- **Documentation**
- Update documentations on autodiff (1550) (by **彭于斌**)
- **Error messages**
- Improve error message when using non-global variables in global operations (1606) (by **彭于斌**)
- **Examples**
- Add comet.py and fix to_numpy() on sparse matrix fields (1583) (by **彭于斌**)
- **GUI**
- Support gui.lines for batched line drawing (1603) (by **彭于斌**)
- **Infrastructure**
- Add "ti.profiler" (PythonProfiler) for intuitive Python-scope profiling (1493) (by **彭于斌**)
- **IPython and other shells**
- 'ti.sync()' is no longer needed for 'print()' in OpenGL and Metal backend (1546) (by **彭于斌**)

Full changelog:
- [misc] Revert 1493 (1622) (by **Taichi Gardener**)
- [misc] Revert 1550 (1621) (by **Taichi Gardener**)
- [Doc] [autodiff] Update documentations on autodiff (1550) (by **彭于斌**)
- [Example] Add comet.py and fix to_numpy() on sparse matrix fields (1583) (by **彭于斌**)
- [misc] [refactor] 'ti.vec' and 'ti.veci' is deprecated, directly use a tuple in GUI system instead (1605) (by **彭于斌**)
- [doc] Workflow for writing a Python test for 1462 (1475) (by **彭于斌**)
- [Infra] Add "ti.profiler" (PythonProfiler) for intuitive Python-scope profiling (1493) (by **彭于斌**)
- [test] [refactor] Add ti.test decorators to unify testing infrastructure (1462) (by **彭于斌**)
- [async] Compute offloaded IR hash once and cache it (1608) (by **Ye Kuang**)
- [Bug] [opt] Fix compiler error when flattening if(0) and if(1) (1613) (by **xumingkuan**)
- [IPython] 'ti.sync()' is no longer needed for 'print()' in OpenGL and Metal backend (1546) (by **彭于斌**)
- [Error] Improve error message when using non-global variables in global operations (1606) (by **彭于斌**)
- [GUI] Support gui.lines for batched line drawing (1603) (by **彭于斌**)

Highlights:
- **OpenGL backend**
- Support ti.block_dim as block size hint (1602) (by **彭于斌**)
- Support TLS to improve reduction performance (1574) (by **彭于斌**)

Full changelog:
- [OpenGL] [perf] Support ti.block_dim as block size hint (1602) (by **彭于斌**)
- [opengl] [refactor] Fix TLS not working and refactor ParallelSize for grid-stride-loop (1600) (by **彭于斌**)
- [async] Demote struct-fors in async compilation (1593) (by **Ye Kuang**)
- [ir] Make sure "StmtFieldManager" to be correct if we modify some fields after the ctor (1587) (by **Xuanda Yang**)
- [ipython] [refactor] Misc tweaks to make 1308 easier to review (1584) (by **彭于斌**)
- [OpenGL] [perf] Support TLS to improve reduction performance (1574) (by **彭于斌**)

Highlights:
- **Language and syntax**
- Support SNode trailing bits (1558) (by **Yuanming Hu**)
- **OpenGL backend**
- Support 'ti.asm' to insert embed GLSL codes (experimental) (1573) (by **彭于斌**)
- **Performance improvements**
- Improve CUDA runtime performance with warp-level primitives (1571) (by **Yuanming Hu**)

Full changelog:
- [cuda] [bug] Fix a CUDA codegen bug (1592) (by **Yuanming Hu**)
- [test] Fix issues in "bls_particle_grid" tests caused by float-point errors (1590) (by **Yuanming Hu**)
- [llvm] Fix LLVM runtime sparse computation issues (1582) (by **Yuanming Hu**)
- [OpenGL] Support 'ti.asm' to insert embed GLSL codes (experimental) (1573) (by **彭于斌**)
- [example] Upgrade mpm88 to new syntax (1581) (by **彭于斌**)
- [gui] [error] [linux] Better error message when X display not available (1575) (by **彭于斌**)
- [test] Skip mpm88 async on Appveyor (1566) (by **Ye Kuang**)
- [Perf] Improve CUDA runtime performance with warp-level primitives (1571) (by **Yuanming Hu**)
- [async] Fuse tasks only if they are either from the same kernel or arg-less (1530) (by **Ye Kuang**)
- [cc] Support ActionRecorder in C backend (1559) (by **彭于斌**)
- [metal] Plug in the SNodeRep structs into codegen (1480) (by **Ye Kuang**)
- [Lang] Support SNode trailing bits (1558) (by **Yuanming Hu**)

Highlights:
- **CUDA backend**
- Upgrade to PTX 6.3 and add a few CUDA intrinsics (1548) (by **Yuanming Hu**)
- **Performance improvements**
- Improve dynamic listgen and access performance (1547) (by **Yuanming Hu**)
- **Refactor**
- 'ti.Matrix(n, m, dt, shape)' is deprecated, use 'ti.Matrix.var(n, m, dt, shape)' instead (1531) (by **彭于斌**)

Full changelog:
- [cc] The C backend is now capable of running mpm128 (1553) (by **彭于斌**)
- [bug] Update mpm_lagrangian_force and fix Matrix constructor (1545) (by **Ye Kuang**)
- [opengl] [refactor] KernelParallelAttribs -> ParallelSize + virtual methods to make a way for grid-stride-loop (1540) (by **彭于斌**)
- [opengl] Fix reversed nested for loops error on OpenGL (1554) (by **彭于斌**)
- [Perf] Improve dynamic listgen and access performance (1547) (by **Yuanming Hu**)
- [cuda] [llvm] Module broken is TI_WARN instead of TI_ERROR (1557) (by **彭于斌**)
- [linux] Fix LLVM symbol leakage in release mode by using RTLD_GLOBAL (1544) (by **彭于斌**)
- [CUDA] Upgrade to PTX 6.3 and add a few CUDA intrinsics (1548) (by **Yuanming Hu**)
- [ir] Move struct-for demotion pass after offload pass (1541) (by **Ye Kuang**)
- [cc] Support "range for" and "while" statement on C backend (1536) (by **彭于斌**)
- [refactor] Better import order by using \_\_all\_\_ (1510) (by **彭于斌**)
- [misc] Add is_path_all_dense to SNode (1538) (by **Ye Kuang**)
- [Refactor] 'ti.Matrix(n, m, dt, shape)' is deprecated, use 'ti.Matrix.var(n, m, dt, shape)' instead (1531) (by **彭于斌**)
- [lang] [refactor] Setup a multipass AST transformer (1467) (by **彭于斌**)