On 22 February 2012 23:52, Ian Lance Taylor <iant@xxxxxxxxxx> wrote: > Ayonam Ray <ayonam@xxxxxxxxx> writes: > >> I'm wondering whether the compiler upon seeing an enum and an >> immediate value as the arguments to the builtin is assuming that the >> builtin does not have or create any dependence on the rest of the >> code. > > That by itself should not do it unless you mark the builtin function as > pure or const, which you did not do. > > I suspect that what is happening is something related but slightly > different. The problem is not the arguments you are passing to the > builtin function, it's the fact that your other code does not depend on > memory, and gcc knows that a function call can only affect memory, > nothing else. So gcc thinks that your other operations are independent > of your builtin function. > > I think you are going to have to expand your builtin function into an > asm very early on, and that asm is going to have to clobber all > registers. There may be some other way to implement this, but offhand I > don't know of one. > > Ian Ian, I will give it a try. Is there a way to mark all registers as clobbered in an RTL (like we can do for memory using (clobber (mem:BLK (const_int 0))) )? Regards Ayonam
