new SSA IL

[Henry Cejtin]

But  in  the function call case, I understand that it is a different binding.
In the SSA case, I can't do that, since all the  variables  look  global  but
initially  un-initialized.   Even  that  sounds pretty imperative.  I guess I
don't see how to think of continuation calling.  In straight  SSA,  there  is
just a phi-function assignment to the args.  In your SSA I see an assignment.
I seem to have to think of it more imperatively  because  of  the  fact  that
there are `other' assignments at other call sites.  (Of course these are part
of the call-ee, not call-er, so they really are the same site.)

I see, the point is that when  you  transform  the  code  in  some  way,  the
dominator tree doesn't change much, but maintaining the block structure would
require more surgery, correct?

As to the guide, the main thing that I need (I think) is an overview  of  the
compiler.  When ever I try to look at it I find myself lost.  Part of this is
your highly structure-ized style.  I'm not arguing against it,  just  that  I
don't understand how to navigate in it.  I keep seeing big .cm files and have
no idea how to find a definition given a use.  Any commentary would be great,
including any summary of your style of functor/structure/signature stuff.