[StrTable] Mechanically convert Hexagon builtins to use TableGen (#123460)

This switches them to use the common builtin TableGen emission.

The fancy feature string preprocessor tricks are replaced with a fairly
direct translation into TableGen.

All of the actual definitions were created using a quite hack-y Python
script that was never intended to be productionized. It preserves the
order, spacing, and even comments from the original files. For
posterity, the script used is here:

https://gist.github.com/chandlerc/f53c7d735e33eecf388529bd9a6010df

The original `.def` file appears to be generated by some out-of-tree
`iset.py` script, which because it is out of tree I couldn't update. It
should be very straightforward though to update it to generate a similar
structure as was used to produce the `.td` file.

In addition to helping move towards TableGen for all of the builtins,
these builtins in particular can be *much* more efficiently handled
using TableGen when we start emitting string tables for them because it
allows de-duplicating all of the feature strings.

The commit sha parent at the time the PR was made is
7253c6fde498c4c9470b681df47d46e6930d6a02 and at that commit, the
resulting TableGen file produces a `.inc` file that only differs in
whitespace and the order of the builtins defined.

GitOrigin-RevId: 7e22180c20fa3b4e0add41ad620d2eaac2b47fcc
7 files changed
tree: bed1a297ceddab45623f5c0978f557cd945bca78
  1. bindings/
  2. cmake/
  3. docs/
  4. examples/
  5. include/
  6. lib/
  7. runtime/
  8. test/
  9. tools/
  10. unittests/
  11. utils/
  12. www/
  13. .clang-format
  14. .clang-tidy
  15. .gitignore
  16. CMakeLists.txt
  17. INSTALL.txt
  18. LICENSE.TXT
  19. Maintainers.rst
  20. NOTES.txt
  21. README.md
README.md

C language Family Front-end

Welcome to Clang.

This is a compiler front-end for the C family of languages (C, C++ and Objective-C) which is built as part of the LLVM compiler infrastructure project.

Unlike many other compiler frontends, Clang is useful for a number of things beyond just compiling code: we intend for Clang to be host to a number of different source-level tools. One example of this is the Clang Static Analyzer.

If you're interested in more (including how to build Clang) it is best to read the relevant websites. Here are some pointers: