[PATCH][middle-end][i386][Version 4] Add -fzero-call-used-regs=[skip|used-gpr-arg|used-arg|all-arg|used-gpr|all-gpr|used|all]

[Qing Zhao]

Okay, I will change it to namespace.

Qing

> On Oct 28, 2020, at 9:19 AM, Richard Sandiford <richard.sandiford@arm.com> wrote:
> 
> Qing Zhao <QING.ZHAO@ORACLE.COM <mailto:QING.ZHAO@ORACLE.COM>> writes:
>> Hi, Richard,
>> 
>> In order to be consistent with other flags in flag-types.h, for example, “sanitize_code”,
>> I didn’t use namespace, instead making the name more specific as following:
>> 
>> /* Different settings for zeroing subset of registers.  */
>> enum  zero_regs_flags {
>>  ZERO_REGS_UNSET = 0,
>>  ZERO_REGS_SKIP = 1UL << 0,
>>  ZERO_REGS_ONLY_USED = 1UL << 1,
>>  ZERO_REGS_ONLY_GPR = 1UL << 2,
>>  ZERO_REGS_ONLY_ARG = 1UL << 3,
>>  ZERO_REGS_ENABLED = 1UL << 4,
>>  ZERO_REGS_USED_GPR_ARG = ZERO_REGS_ENABLED | ZERO_REGS_ONLY_USED
>>                           | ZERO_REGS_ONLY_GPR | ZERO_REGS_ONLY_ARG,
>>  ZERO_REGS_USED_GPR = ZERO_REGS_ENABLED | ZERO_REGS_ONLY_USED
>>                       | ZERO_REGS_ONLY_GPR,
>>  ZERO_REGS_USED_ARG = ZERO_REGS_ENABLED | ZERO_REGS_ONLY_USED
>>                       | ZERO_REGS_ONLY_ARG,
>>  ZERO_REGS_USED = ZERO_REGS_ENABLED | ZERO_REGS_ONLY_USED,
>>  ZERO_REGS_ALL_GPR_ARG = ZERO_REGS_ENABLED | ZERO_REGS_ONLY_GPR
>>                          | ZERO_REGS_ONLY_ARG,
>>  ZERO_REGS_ALL_GPR = ZERO_REGS_ENABLED | ZERO_REGS_ONLY_GPR,
>>  ZERO_REGS_ALL_ARG = ZERO_REGS_ENABLED | ZERO_REGS_ONLY_ARG,
>>  ZERO_REGS_ALL = ZERO_REGS_ENABLED
>> };
>> 
>> Is this good?
>> 
>> Or you still prefer namespace?
> 
> I prefer the namespace.  I realise namespaces aren't used that much
> in GCC yet, but they *are* used.
> 
> The advantage they have is that it's possible to do:
> 
>  using namespace ...;
> 
> in contexts where there's no ambiguity.  They also make lines like
> the | ones above easier to read.
> 
> Thanks,
> Richard