Hi all,
I'm looking at implementing target attributes for aarch64 and I have some
questions about the hooks involved.
I haven't looked at this part of the compiler before, so forgive me if some of
them seem obvious. I couldn't
figure it out from the documentation
(https://gcc.gnu.org/onlinedocs/gccint/Target-Attributes.html#Target-Attributes)
* Seems to me that TARGET_OPTION_VALID_ATTRIBUTE_P is the most important one
that parses
the string inside the __attribute__ ((target ("..."))) and sets the
target-specific
flags appropriately. Is that correct?
* What is TARGET_ATTRIBUTE_TABLE used for? It's supposed to map attributes to
handlers?
Isn't that what TARGET_OPTION_VALID_ATTRIBUTE_P is for?
* What is the use of TARGET_OPTION_SAVE and TARGET_OPTION_RESTORE? Is that used
during
something like LTO when different object files and functions are compiled with
different
flags? Are these functions just supposed to 'backup' various tuning and ISA
decisions?
* Is TARGET_COMP_TYPE_ATTRIBUTES the one that's supposed to handle incompatible
attributes
being specified? (for example incompatible endianness or architecture levels)?
Thanks for any insight,
Kyrill
