Some clarifications regarding GIMPLE and LTO

2006-11-26 Thread nkavv 
Hi there

i'm looking for a way to emit (dump) complete global and local symbol table
entries for any given (C) program. For now, it would be satisfactory if this
was properly handled for single-source-file programs. But what i would like to
do basically is to store the entire information that would be needed in order
to interpret a GIMPLE dump.

A HLL (high-level language) program would probably map into something like this
by any compiler:

record Program is
  record GlobalSymbolTable is
// global symbol entries
  end record;
  list FunctionList is
// a linked list of Function records as defined below
  end list;
end record;

record Function is
  record LocalSymbolTable is
  // local symbol entries
  end record;
  record StatementList is
  // list of low-GIMPLE-level statements
  end record;
end record;

What I can see now is that GlobalSymbolTable is not dumped at all and
LocalSymbolTable entries are not dumped to full extent (e.g. no
initializations). For example, struct cgraph_varpool_node does not carry all
the required information, for global variables and maybe it wasn't designed for
that either.

Does the LTO branch try to achieve that the complete information for a Program
can be sufficiently stored (in a file)? If this is already there, could anyone
provide some pointers to the API?

Thank you in advance.

Kind regards
Nikolaos Kavvadias

Re: Some clarifications regarding GIMPLE and LTO

2006-11-26 Thread Mark Mitchell 
[EMAIL PROTECTED] wrote:

 Does the LTO branch try to achieve that the complete information for a 
 Program
 can be sufficiently stored (in a file)? If this is already there, could anyone
 provide some pointers to the API?

Yes, on the LTO branch, we are working to store the entire translation
unit in a form that can then be read back into the compiler.  The global
symbol table is stored using DWARF3, so you can read it back with a
standard DWARF reader.  See lto/lto.c on the LTO branch for the code
that does this.

At present, there are a few things that are not yet written out to the
DWARF information (like GCC machine modes), but most things (types,
functions, variables) are present.

-- 
Mark Mitchell
CodeSourcery
[EMAIL PROTECTED]
(650) 331-3385 x713