macOS 12.3 no longer ships non-3 python.
Almost all of these scripts were launched by ninja, and the GN files
already told it to run them under python3, so this is a fairly small
change. The main effect is that if you run them manually, you now
get the same behavior.
(A small set of scripts, gn.py, gen.py, sync_source_lists_from_cmake.py,
are for manual running. For these, it is an actual change.)
Differential Revision: https://reviews.llvm.org/D122345
Also adds a boring build file for llvm/lib/BinaryFormat (needed by llvm/lib/IR).
lib/IR marks Attributes and IntrinsicsEnum as public_deps (because IR's public
headers include the generated .inc files), so projects depending on lib/IR will
implicitly depend on them being generated. As a consequence, most targets won't
have to explicitly list a dependency on these tablegen steps (contrast with
intrinsics_gen in the cmake build).
This doesn't yet have the optimization where tablegen's output is only updated
if it's changed.
Differential Revision: https://reviews.llvm.org/D55028#inline-486755
llvm-svn: 347927
Nico Weber