[llvm-objdump] Switch command-line parsing from llvm::cl to OptTable

Authored by thakis on Apr 12 2021, 7:31 PM.


[llvm-objdump] Switch command-line parsing from llvm::cl to OptTable

This is similar to D83530, but for llvm-objdump.

The motivation is the desire to add an llvm-otool symlink to
llvm-objdump that behaves like macOS's otool, using the same
technique the at llvm-objcopy uses to behave like strip (etc).

This change for the most part preserves behavior. In some cases,
it increases compatibility with GNU objdump a bit. For example,
the long options now require two dashes, and the long options
taking arguments for the most part now require a = in front
of the value. Exceptions are flags where tests passed the
value separately, for these the separate form is kept as
an alias to the = form.

The one-letter short form args are now joined or separate
and long longer accept a =, which also matches GNU objdump.

cl::opt<>s in libraries now have to be explicitly plumbed
through. This patch does that for --x86-asm-syntax=, but
there's hope that we can remove that again.

Differential Revision: https://reviews.llvm.org/D100433