[LLVMdev] Top Level Stuff

[Chris Lattner]

On Sun, 1 Jul 2007, Tanya M. Lattner wrote:
> I don't think we should have a docs module. Its much better to allow a
> person to check out only llvm and get the appropriate documentation. Same
> for hlvm, and whatever project. Its very inconvenient to check out
> multiple things just to get llvm and docs.

To put it another way, I think the docs for the subproject should follow 
the subproject.

>> 4. /utils/ (or perhaps /tools/)
>> I think there's an opportunity for us to put some common tools that are
>> used by several modules into a top level module named /utils/. Initially
>> this could be a merge of the hlvm and llvm module /utils/ directory
>> (excluding things like tblgen which is llvm specific).
>
> What tools are common? This is another thing someone has to check out.

I think that there is common stuff, but we should keep it as minimal as 
possible.  I think that llvm-config should be common, but can't think of 
anything else that should be.

In particular, with a unified llvm-project world, I think checking out 
llvm-project should give you something like this:

mydir/llvm-project/
                    llvm-config/*
                    README.txt
                    Makefile

And probably nothing else.

Importantly, the README.txt would talk about how to use the makefile, 
suggesting common things, like:

make checkout PROJECT=llvm-gcc

which checks out llvm-gcc and all dependencies.


The makefile itself would have no project-specific details in it, it would 
require all the projects to be self describing about their dependencies. 
llvm-gcc depends on llvm which depends on llvm-support or something. 
'make checkout' would check out the requested project, then recursively 
check out its dependencies.

This would give you a tree like this:

mydir/llvm-project/
                    llvm-config/*
                    llvm/* {lib/utils/tools/include/...}
                    llvm-gcc/* {gcc/fastjar/intl/zlib/...}
                    support/*  {lib/include}
                    README.txt
                    Makefile

The ability for the makefile to drive an arbitrary build system is pretty 
important.  We already have llvm and llvm-gcc which have totally different 
build systems.  By having the top-level independent of any individual 
build system, we can independently move things to scons or whatever with 
little pain (just have a text file in the top-level of each project that 
says "run this command to build me" "run this command to test me" etc).

-Chris

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