[LLVMdev] Simplifying a front-end project

[Bagel]

Vikram, I have implemented a front-end for a new language that generates LLVM 
assembly language.  I used that approach for three reasons:

1. The API learning curve looked steep.
2. It is easy to read the LLVM assembly source to see if things are correct.
3. But mainly, I wanted to implement my front-end in my new language, so
    the C/C++ bindings might not be applicable or easy to use.

Each node of my AST is typed.  As I generate for it, I give it a
unique sequence number.  Then I use a printf-like format to describe the 
output.  Here's what generating for an ADD AST looks like:

   GenSub(node at .child[0]);
   GenSub(node at .child[1]);
   Tseqno += 1;  node at .seqno = Tseqno;
   Print("\t%N = add %T %0N, %1N\n", node);

This recursively generates the left and right side of the node, gives the node 
a sequence number and then prints the LLVM assembly.  In the format:
%N - prints node name
%T - prints node type
%0N - prints node name of child 0
%1N - prints node name of child 1

Obviously, there's more to it than that; but that's the general approach.