PING [Patch][Middle-end]Add -fzero-call-used-regs=[skip|used-gpr|all-gpr|used|all]

[Qing Zhao]

>> 
>>> If so, I am okay with name “call-clobbered” if this name sounds better. 
>> 
>> It's more obvious, at least to me.

In the current option list of GCC:  https://gcc.gnu.org/onlinedocs/gcc/Code-Gen-Options.html#Code-Gen-Options <https://gcc.gnu.org/onlinedocs/gcc/Code-Gen-Options.html#Code-Gen-Options>

There is one available option whose name is: -fcall-used-reg


-fcall-used-reg

Treat the register named reg as an allocable register that is clobbered by function calls. It may be allocated for temporaries or variables that do not live across a call. Functions compiled this way do not save and restore the register reg.

It is an error to use this flag with the frame pointer or stack pointer. Use of this flag for other registers that have fixed pervasive roles in the machine’s execution model produces disastrous results.

This flag does not have a negative form, because it specifies a three-way choice.

So, the name of this option adopted “call-used” instead of “call-clobbered”.  I think that for consistency, it might be still better to use “-fzero-call-used-regs” instead of “-fzero-call-clobbered-regs”?

Qing





> Okay. 
>