On Wed, May 26, 2010 at 08:09:57PM +0200, Ulrich Weigand wrote: > Mike Meissner wrote: > > On Wed, May 26, 2010 at 10:16:22AM -0700, Mark Mitchell wrote: > > > Ulrich Weigand wrote: > > > > > > >> So the question is: The goal is to have hooks, not macros, right? If > > > >> so, can reviewers please take care to reject patches that introduce > > > >> new macros? > > > > > > > > I don't know to which extent this is a formal goal these days, but I > > > > personally agree that it would be nice to eliminate macros. > > > > > > Yes, the (informally agreed) policy is to have hooks, not macros. There > > > may be situations where that is technically impossible, but I'd expect > > > those to be very rare. > > > > For the target address space stuff, it is to the __ea keyword. You don't > > want > > a target hook that is called on every identifier, but instead you want a > > target > > hook that is called in c_parse_init (in c-parser.c) and init_reswords (in > > cp/lex.c) to set up the keywords. The target hook would have to duplicate > > the > > functionality of all of the setup that c_parse_init and init_reswords do, > > particularly if they have different semantics. > > It looks like this may be simpler than I thought. The following patch > introduces a "c_register_addr_space" routine that the back-end may call > to register a named address space qualifier keyword. (This could be done > either statically at start-up, or even dynamically e.g. in respose to a > target-specific #pragma.) > > In the current patch, the SPU back-end uses somewhat of a hack to actually > perform that call: it is included in the REGISTER_TARGET_PRAGMAS macro. > Note that this macro is already being used by the SPU and several other > back-end for similar hacks. It seems that it might be a good idea to > replace this by something like a "register_target_extensions" callback > in targetcm, but that can probably be done in a separate patch.
Note, many of the things done by REGISTER_TARGET_PRAGMAS deal with the preprocessor and keywords, which are used by the C-like front ends, but not used for Ada, Fortran, etc. Those front ends don't link in libcpp. So, you need something in <machine>-c.c that sets the hook, rather than moving it to <machine>.c. -- Michael Meissner, IBM Until June 14: 4 Technology Place Drive, MS 2203A, Westford, MA, 01886, USA After June 14: 5 Technology Place Drive, MS 2757, Westford, MA 01886, USA meiss...@linux.vnet.ibm.com
