[Mesa-dev] obtain def-use chain in glsl s-expression

[Liu Xin]

Hi, Mesa community,

I am not familiar with S-expression or other forms of lisp languages. I 
am working on GLSL IR transformation.  for example, i want to change a 
variable to a array of same type.

By now , i can find the definition of a variable. How can i update all 
uses of this variable in S-expression? I think all uses of this variable 
are in the form of ir_dereference_variable. The difficulty is how to 
collect d-u chain using hierarchical visitor.  I think some optimizer 
authors  must have the same problem. Could you give me a pass which 
solved my problem?  so I can take reference.

thanks,
--lx