From 3974200ffd9dafa7874221910611d07fb341435e Mon Sep 17 00:00:00 2001 From: dj Date: Fri, 5 Sep 2003 02:12:29 +0000 Subject: * targhooks.c: Add comment explaining the migration process. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@71103 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/targhooks.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'gcc/targhooks.c') diff --git a/gcc/targhooks.c b/gcc/targhooks.c index 7654e230b83..97d0642540b 100644 --- a/gcc/targhooks.c +++ b/gcc/targhooks.c @@ -18,6 +18,35 @@ along with GCC; see the file COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ +/* The migration of target macros to target hooks works as follows: + + 1. Create a target hook that uses the existing target macros to + implement the same functionality. + + 2. Convert all the MI files to use the hook instead of the macro. + + 3. Repeat for a majority of the remaining target macros. This will + take some time. + + 4. Tell target maintainers to start migrating. + + 5. Eventually convert the backends to override the hook instead of + defining the macros. This will take some time too. + + 6. TBD when, poison the macros. Unmigrated targets will break at + this point. + + Note that we expect steps 1-3 to be done by the people that + understand what the MI does with each macro, and step 5 to be done + by the target maintainers for their respective targets. + + Note that steps 1 and 2 don't have to be done together, but no + target can override the new hook until step 2 is complete for it. + + Once the macros are poisoned, we will revert to the old migration + rules - migrate the macro, callers, and targets all at once. This + comment can thus be removed at that point. */ + #include "config.h" #include "system.h" #include "coretypes.h" -- cgit v1.2.1