Re: [dpdk-dev] [PATCH v3] build: fix SVE compile error with gcc8.3

[fengchengwen <fengchengwen@huawei.com>]

Hi, Thomas

This patch already reviewed by ARM guys.

Please review it, thanks


On 2021/6/12 15:07, fengchengwen wrote:
> Friendly ping
> 
> 
> On 2021/5/27 15:12, Fengchengwen wrote:
>> Hi, Thomas
>>
>>     Could you review this patch? Thanks
>>
>>
>> From:Ruifeng Wang <Ruifeng.Wang@arm.com>
>> To:Fengchengwen <fengchengwen@huawei.com>;Thomas Monjalon <thomas@monjalon.net>;ferruh.yigit <ferruh.yigit@intel.com>
>> Cc:dev <dev@dpdk.org>;Richardson, Bruce <bruce.richardson@intel.com>;vladimir.medvedkin <vladimir.medvedkin@intel.com>;viktorin <viktorin@rehivetech.com>;Jerin Jacob <jerinj@marvell.com>;nd <nd@arm.com>
>> Date:2021-05-25 14:02:20
>> Subject:RE: [PATCH v3] build: fix SVE compile error with gcc8.3
>>
>>> -----Original Message-----
>>> From: Chengwen Feng < fengchengwen@huawei.com<mailto:fengchengwen@huawei.com>>
>>> Sent: Friday, May 21, 2021 9:53 AM
>>> To: thomas@monjalon.net<mailto:thomas@monjalon.net>; ferruh.yigit@intel.com<mailto:ferruh.yigit@intel.com>; Ruifeng Wang
>>> < Ruifeng.Wang@arm.com<mailto:Ruifeng.Wang@arm.com>>
>>> Cc: dev@dpdk.org<mailto:dev@dpdk.org>; bruce.richardson@intel.com<mailto:bruce.richardson@intel.com>;
>>> vladimir.medvedkin@intel.com<mailto:vladimir.medvedkin@intel.com>; viktorin@rehivetech.com<mailto:viktorin@rehivetech.com>;
>>> jerinj@marvell.com<mailto:jerinj@marvell.com>
>>> Subject: [PATCH v3] build: fix SVE compile error with gcc8.3
>>>
>>> If the target machine has SVE feature (e.g. "-march=armv8.2-a+sve'), and the
>>> compiler are gcc8.3, it will compile error:
>>>        In file included from ../dpdk-next-net/lib/eal/common/
>>>        eal_common_options.c:38:
>>>        ../dpdk-next-net/lib/eal/arm/include/rte_vect.h:13:10: fatal
>>>        error: arm_sve.h: No such file or directory
>>>        #include <arm_sve.h>
>>>               ^~~~~~~~~~~
>>>        compilation terminated.
>>>
>>> The root cause is that gcc8.3 supports SVE (the macro __ARM_FEATURE_SVE
>>> was 1), but it doesn't support SVE ACLE [1].
>>>
>>> The solution:
>>> a) Detect compiler whether support SVE ACLE, if support then define
>>> CC_SVE_ACLE_SUPPORT macro.
>>> b) Use the CC_SVE_ACLE_SUPPORT macro to include SVE header file.
>>>
>>> [1] ACLE: Arm C Language Extensions, the SVE ACLE header file is
>>> <arm_sve.h>, user should include it when writing ACLE SVE code.
>>>
>>> Fixes: 67b68824a82d ("lpm/arm: support SVE")
>>>
>>> Signed-off-by: Chengwen Feng < fengchengwen@huawei.com<mailto:fengchengwen@huawei.com>>
>>> ---
>>> v3:
>>> * double-indent 'cc.check_header('arm_sve.h')' line
>>> * move set 'CC_SVE_ACLE_SUPPORT' logic to the back (not in the middle
>>>   of compile_time_cpuflags setting)
>>> * fix minor syntax error in commit log
>>> v2:
>>> * modify title start with 'build'
>>>
>>> ---
>>> config/arm/meson.build         | 5 +++++
>>> lib/eal/arm/include/rte_vect.h | 2 +-
>>> lib/lpm/rte_lpm.h              | 2 +-
>>> 3 files changed, 7 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/config/arm/meson.build b/config/arm/meson.build index
>>> e83a56e..08299b0 100644
>>> --- a/config/arm/meson.build
>>> +++ b/config/arm/meson.build
>>> @@ -488,3 +488,8 @@ if cc.get_define('__ARM_FEATURE_CRYPTO', args:
>>> machine_args) != ''
>>>      compile_time_cpuflags += ['RTE_CPUFLAG_AES', 'RTE_CPUFLAG_PMULL',
>>>      'RTE_CPUFLAG_SHA1', 'RTE_CPUFLAG_SHA2'] endif
>>> +
>>> +if (cc.get_define('__ARM_FEATURE_SVE', args: machine_args) != '' and
>>> +        cc.check_header('arm_sve.h'))
>>> +    dpdk_conf.set('CC_SVE_ACLE_SUPPORT', 1) endif
>>> diff --git a/lib/eal/arm/include/rte_vect.h b/lib/eal/arm/include/rte_vect.h
>>> index 093e912..277b656 100644
>>> --- a/lib/eal/arm/include/rte_vect.h
>>> +++ b/lib/eal/arm/include/rte_vect.h
>>> @@ -9,7 +9,7 @@
>>> #include "generic/rte_vect.h"
>>> #include "rte_debug.h"
>>> #include "arm_neon.h"
>>> -#ifdef __ARM_FEATURE_SVE
>>> +#ifdef CC_SVE_ACLE_SUPPORT
>>> #include <arm_sve.h>
>>> #endif
>>>
>>> diff --git a/lib/lpm/rte_lpm.h b/lib/lpm/rte_lpm.h index 28b5768..9262814
>>> 100644
>>> --- a/lib/lpm/rte_lpm.h
>>> +++ b/lib/lpm/rte_lpm.h
>>> @@ -402,7 +402,7 @@ rte_lpm_lookupx4(const struct rte_lpm *lpm, xmm_t
>>> ip, uint32_t hop[4],
>>>        uint32_t defv);
>>>
>>> #if defined(RTE_ARCH_ARM)
>>> -#ifdef __ARM_FEATURE_SVE
>>> +#ifdef CC_SVE_ACLE_SUPPORT
>>> #include "rte_lpm_sve.h"
>>> #else
>>> #include "rte_lpm_neon.h"
>>> --
>>> 2.8.1
>>
>> Acked-by: Ruifeng Wang < ruifeng.wang@arm.com<mailto:ruifeng.wang@arm.com>>
>>