Re: [PATCH v4 2/2] xen: debug: gcov: add condition coverage support

[Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>]

Hi Jan,

Jan Beulich <jbeulich@suse.com> writes:

> On 07.04.2025 18:46, Volodymyr Babchuk wrote:
>> --- a/xen/Rules.mk
>> +++ b/xen/Rules.mk
>> @@ -31,6 +31,7 @@ CFLAGS-y :=
>>  AFLAGS-y :=
>>  nocov-y :=
>>  noubsan-y :=
>> +cov-flags-y :=
>
> Personally I would have put this slightly higher up, at least ahead of the two
> no*-y. Thinking of it only now (sorry), also maybe cov-cflags-y might be
> slightly better a name?

Okay, I'll do this in the next version.

>
>> @@ -133,19 +134,18 @@ $(filter %.init.o,$(obj-y) $(obj-bin-y) $(extra-y)): CFLAGS-y += -DINIT_SECTIONS
>>  
>>  non-init-objects = $(filter-out %.init.o, $(obj-y) $(obj-bin-y) $(extra-y))
>>  
>> -ifeq ($(CONFIG_COVERAGE),y)
>>  ifeq ($(CONFIG_CC_IS_CLANG),y)
>> -    COV_FLAGS := -fprofile-instr-generate -fcoverage-mapping
>> +    cov-flags-$(CONFIG_COVERAGE) := -fprofile-instr-generate -fcoverage-mapping
>>  else
>> -    COV_FLAGS := -fprofile-arcs -ftest-coverage
>> +    cov-flags-$(CONFIG_COVERAGE) := -fprofile-arcs -ftest-coverage
>> +    cov-flags-$(CONFIG_CONDITION_COVERAGE) += -fcondition-coverage
>
> Why's this inside the remaining ifeq(,)? Surely there's at least a chance for
> Clang to also support the option at some point?

Yes, but Clang uses different option: -fcoverage-mcdc. I see no sense in
adding it right now, as Xen does not support version 10 of llvm
profiling format, in which they added MC/DC support.

-- 
WBR, Volodymyr