[dpdk-dev] [PATCH 2/2] net/hns3: fix SVE code compile error with gcc8.3

[Chengwen Feng]

If the target machine has SVE feature (e.g. '-march=armv8.2-a+sve'),
and compiler are gcc8.3, it will compile error, the error is arm_sve.h
no such file or directory.

The solution:
a. If RTE_HAS_SVE_ACLE defined (it means the minimum instruction set
support SVE ACLE) then compiles it.
b. Else if the compiler support SVE ACLE then compiles it.
c. Otherwise don't compile it.

Fixes: 8c25b02b082a ("net/hns3: fix enabling SVE Rx/Tx")
Fixes: 952ebacce4f2 ("net/hns3: support SVE Rx")
Cc: stable at dpdk.org

Signed-off-by: Chengwen Feng <fengchengwen at huawei.com>
Acked-by: Ruifeng Wang <ruifeng.wang at arm.com>
---
 drivers/net/hns3/hns3_rxtx.c |  2 +-
 drivers/net/hns3/meson.build | 20 +++++++++++++++++++-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/drivers/net/hns3/hns3_rxtx.c b/drivers/net/hns3/hns3_rxtx.c
index cb9eccf..a86e105 100644
--- a/drivers/net/hns3/hns3_rxtx.c
+++ b/drivers/net/hns3/hns3_rxtx.c
@@ -2811,7 +2811,7 @@ hns3_get_default_vec_support(void)
 static bool
 hns3_get_sve_support(void)
 {
-#if defined(RTE_ARCH_ARM64) && defined(__ARM_FEATURE_SVE)
+#if defined(RTE_HAS_SVE_ACLE)
 	if (rte_vect_get_max_simd_bitwidth() < RTE_VECT_SIMD_256)
 		return false;
 	if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_SVE))
diff --git a/drivers/net/hns3/meson.build b/drivers/net/hns3/meson.build
index 53c7df7..a99e0db 100644
--- a/drivers/net/hns3/meson.build
+++ b/drivers/net/hns3/meson.build
@@ -35,7 +35,25 @@ deps += ['hash']
 
 if arch_subdir == 'arm' and dpdk_conf.get('RTE_ARCH_64')
     sources += files('hns3_rxtx_vec.c')
-    if cc.get_define('__ARM_FEATURE_SVE', args: machine_args) != ''
+
+    # compile SVE when:
+    # a. support SVE in minimum instruction set baseline
+    # b. it's not minimum instruction set, but compiler support
+    if dpdk_conf.has('RTE_HAS_SVE_ACLE')
         sources += files('hns3_rxtx_vec_sve.c')
+    elif cc.has_argument('-march=armv8.2-a+sve') and cc.check_header('arm_sve.h')
+        cflags += ['-DRTE_HAS_SVE_ACLE=1']
+        sve_cflags = []
+        foreach flag: cflags
+            if not (flag.startswith('-march=') or flag.startswith('-mcpu=') or flag.startswith('-mtune='))
+                sve_cflags += flag
+            endif
+        endforeach
+        hns3_sve_lib = static_library('hns3_sve_lib',
+                        'hns3_rxtx_vec_sve.c',
+                        dependencies: [static_rte_ethdev],
+                        include_directories: includes,
+                        c_args: [sve_cflags, '-march=armv8.2-a+sve'])
+        objs += hns3_sve_lib.extract_objects('hns3_rxtx_vec_sve.c')
     endif
 endif
-- 
2.8.1