Generate tree/rtx for address-of exp?

[Jim Wilson]

MajorZ wrote:
> 1. Is there a universal field in tree/rtx for
> address-of exp? No matter what exp could be.

No.

> 2. Is there some function A that could help to
> calculate the offset no matter it is structure, array
> or mix?

Create an ADDR_EXPR tree, and pass it to expand_expr.  That will return 
RTL corresponding to the address.  If you want the address of a struture 
member, then you need a ADDR_EXPR of a COMPONENT_REF tree.  Etc.

> 3. Can some nice guy could should me the simple
> pseudocode for the function A if I have to write it
> myself? Or what are the situations I need to think of,
> like for array, for strcuture, for arrays of strutures
> etc.

Write a simple C testcase, run gdb on cc1, put a breakpoint in 
expand_expr in the ADDR_EXPR case, and then print out the tree with the 
pt gdb macro (or use debug_tree directly).
-- 
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com