config/arm: use native machine build arguments

Letting the compiler decide is going to yield the best results for
native builds, so use native machine args usable for both GCC and Clang.

Signed-off-by: Juraj Linkeš <juraj.linkes@pantheon.tech>
Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
Acked-by: Jerin Jacob <jerinj@marvell.com>
Tested-by: Jerin Jacob <jerinj@marvell.com>
Tested-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
Tested-by: Vimal Chungath <vcchunga@amazon.com>
Tested-by: Dharmik Thakkar <dharmik.thakkar@arm.com>

diff --git a/config/arm/meson.build b/config/arm/meson.build
index be92630..9c33490 100644 (file)
--- a/config/arm/meson.build
+++ b/config/arm/meson.build
@@ -2,8 +2,6 @@
 # Copyright(c) 2017 Intel Corporation.
 # Copyright(c) 2017 Cavium, Inc
 
-arm_force_native_march = false
-
 # common flags to all aarch64 builds, with lowest priority
 flags_common = [
        # Accelerate rte_memcpy. Be sure to run unit test (memcpy_perf_autotest)
@@ -26,6 +24,7 @@ flags_common = [
        ['RTE_ARCH_ARM64', true],
        ['RTE_CACHE_LINE_SIZE', 128]
 ]
+native_machine_args = ['-mcpu=native']
 
 ## Part numbers are specific to Arm implementers
 # implementer specific aarch64 flags have middle priority
@@ -46,7 +45,6 @@ implementer_generic = {
 }
 
 part_number_config_arm = {
-       'native': {'machine_args':  ['-march=native']},
        '0xd03': {'machine_args':  ['-mcpu=cortex-a53']},
        '0xd04': {'machine_args':  ['-mcpu=cortex-a35']},
        '0xd07': {'machine_args':  ['-mcpu=cortex-a57']},
@@ -101,7 +99,6 @@ implementer_cavium = {
                ['RTE_MAX_NUMA_NODES', 2]
        ],
        'part_number_config': {
-               'native': {'machine_args': ['-march=native']},
                '0xa1': {
                        'machine_args': ['-mcpu=thunderxt88'],
                        'flags': flags_part_number_thunderx
@@ -151,8 +148,7 @@ implementer_ampere = {
        ],
        'part_number_config': {
                '0x0': {'machine_args':  ['-march=armv8-a+crc+crypto',
-                                         '-mtune=emag']},
-               'native': {'machine_args':  ['-march=native']}
+                                         '-mtune=emag']}
        }
 }
 
@@ -201,26 +197,27 @@ if dpdk_conf.get('RTE_ARCH_32')
        machine_args += '-mfpu=neon'
 else
        # aarch64 build
-       if machine == 'default' and not meson.is_cross_build()
-               # default build
-               implementer_id = 'generic'
-               part_number = 'generic'
-       elif not meson.is_cross_build()
-               # native build
-               # The script returns ['Implementer', 'Variant', 'Architecture',
-               # 'Primary Part number', 'Revision']
-               detect_vendor = find_program(join_paths(
-                               meson.current_source_dir(), 'armv8_machine.py'))
-               cmd = run_command(detect_vendor.path())
-               if cmd.returncode() == 0
-                       cmd_output = cmd.stdout().to_lower().strip().split(' ')
-                       implementer_id = cmd_output[0]
-                       part_number = cmd_output[3]
+       use_native_machine_args = false
+       if not meson.is_cross_build()
+               if machine == 'default'
+                       # default build
+                       implementer_id = 'generic'
+                       part_number = 'generic'
                else
-                       error('Error when getting Arm Implementer ID and part number.')
-               endif
-               if arm_force_native_march == true
-                       part_number = 'native'
+                       # native build
+                       # The script returns ['Implementer', 'Variant', 'Architecture',
+                       # 'Primary Part number', 'Revision']
+                       detect_vendor = find_program(join_paths(
+                                       meson.current_source_dir(), 'armv8_machine.py'))
+                       cmd = run_command(detect_vendor.path())
+                       if cmd.returncode() == 0
+                               cmd_output = cmd.stdout().to_lower().strip().split(' ')
+                               implementer_id = cmd_output[0]
+                               part_number = cmd_output[3]
+                       else
+                               error('Error when getting Arm Implementer ID and part number.')
+                       endif
+                       use_native_machine_args = true
                endif
        else
                # cross build
@@ -256,7 +253,12 @@ else
 
        # apply supported machine args
        machine_args = [] # Clear previous machine args
-       foreach flag: part_number_config['machine_args']
+       if use_native_machine_args
+               candidate_machine_args = native_machine_args
+       else
+               candidate_machine_args = part_number_config['machine_args']
+       endif
+       foreach flag: candidate_machine_args
                if cc.has_argument(flag)
                        machine_args += flag
                endif