Enable dwarf expansion of @casts

This will iterate over the module and its CUs looking for the type
definition, and then work with loc2c to dereference the pointer.

* loc2c.c (c_translate_argument): Create a dummy location to start
the address computation from a function parameter.
* translate.cxx (base_query, dwarf_query): Move some members from
base_query to dwarf_query, so the former can be more generic.  Also
add a constructor using a module string instead of probe parameters.
(dwflpp::query_modules, dwflpp::iterate_over_modules): Use a generic
base_query instead of a dwarf_query.
(dwarf_cast_query): New query to scan the modules and CUs for a
matching type definition, and then produce a code fragment to deref
each component.
(dwarf_cast_expanding_visitor): Tries to replace @casts with a function
call to the result of a dwarf_cast_query.
(dwflpp::declaration_resolve): Search by name instead of by die.
(dwflpp::translate_components): Use the incoming vardie as the first
type die, so we don't assume that attr_mem has a DW_AT_type already.
(dwflpp::literal_stmt_for_pointer): Construct a C fragment that starts
with a pointer argument (THIS->pointer) and dereferences each member
component from there.
(*_derived_probe::register_patterns): Take a session parameter instead
of a match_node, so we can manipulate session-wide data.
(dwarf_derived_probe::register_patterns): Add a session code filter to
expand @casts with a dwarf_cast_expanding_visitor.

0 files changed, 0 insertions, 0 deletions