exti.c: Optimize multiplexed IRQ handlers.

Rewrite existing IRQ handlers in terms of new functions
dispatch_single_exti() and dispatch_extis().  dispatch_single_exti()
handles EXTIs which have a dedicated IRQ line, and thus doesn't have
to check EXTI_PR; it is mostly equivalent to the (now removed)
handle_exti().  dispatch_extis() handles multiple EXTIs sharing an IRQ
line.  Using dispatch_extis() instead of calling handle_exti()
multiple times avoids unnecessary I/O to the (volatile) EXTI_BASE->PR
register.

These changes are in the flavor of the timer IRQ optimizations
performed in f5016b15bef56bbdfd187f9b623177ef6dde7ace.

0 files changed, 0 insertions, 0 deletions