Add "dumpmachine"/"dumpmachinefull" arguments to get the target machine triplet ("dumpmachinefull" for the full MSVC version).

[falhumai96]

Add two new command-line arguments to get the target machine's triplet, by parsing the command-line output of cl:

• dumpmachine, which is to get the base machine triplet in the format {arch}-pc-windows-msvc, where {arch} is the target archetecture. If the target architecture is ARM or X86, {arch} will be set to armv7 or i386, respectfully (since there are many ARM or X86 archetectures). dumpmachine is similer to that of gcc/clang's command of the same name.
• dumpmachinefull, which has the same output as dumpmachine, except it is post-fixed by the full MSVC version being used. In other words, the command-line argument has the following format {arch}-pc-windows-msvc{msvcver}, where {arch} is the target archetecture and {msvcver} is the MSVC version.

These arguments precede any other arguments passed to cccl, and if dumpmachine/dumpmachinefull is processed, it will print the target triplet and exit succefully (the first of dumpmachine or dumpmachinefull will be processed).

[wsfulton]

This patch needs documenting with the added options like all the other options are documented. Can you point me to some cc compiler that implements -dumpmachinefull?

[falhumai96]

This patch needs documenting with the added options like all the other options are documented. Can you point me to some cc compiler that implements -dumpmachinefull?

I don't think there is a cc-like compiler frontend that has dumpmachinefull. I just added it to have more info on the MSVC version.

But, you are right. I need to add documentation to the code.