ARMv7 (with NEON) can not support on Linux but only support ARMv7 (with NEON) on Android

[candcv]

Hi, I find that XNNPACK can not support ARMv7 (with NEON) on Linux,
but only support ARMv7 (with NEON) on Android?

part error log:
/tensorflow/build_arm/xnnpack/src/qs8-qc8w-igemm/gen/qs8-qc8w-igemm-2x2c4-minmax-fp32-armsimd32.c:80:15: error: unknown type name ‘int16x2_t’ const int16x2_t va1c02 = __sxtb16(va1);

[fbarchard]

armsimd32 is ARMv6 style simd - 4 bytes. It provides optimization on cpus without NEON.

In bazel there is a section with the build options applied:

xnnpack_cc_library(
    name = "armsimd32_bench_microkernels",
    aarch32_copts = [
        "-marm",
        "-march=armv6",
        "-mfpu=vfp",
        "-munaligned-access",
    ],
    aarch32_srcs = ALL_ARMSIMD32_MICROKERNEL_SRCS,
    gcc_copts = xnnpack_gcc_std_copts() + [
        "-fno-fast-math",
        "-fno-math-errno",
    ],
    msvc_copts = xnnpack_msvc_std_copts(),
    deps = [
        ":common",
        ":math",
        ":microkernels_h",
        ":microparams",
        ":prefetch",
        ":tables",
        ":unaligned",
    ],
)

and CMakeLists.txt has similar options

  SET_PROPERTY(SOURCE ${ALL_MICROKERNEL_SRCS} APPEND_STRING PROPERTY COMPILE_FLAGS " -marm ")
  SET_PROPERTY(SOURCE ${PROD_MICROKERNEL_SRCS} APPEND_STRING PROPERTY COMPILE_FLAGS " -marm ")
  SET_PROPERTY(SOURCE ${ALL_ARMSIMD32_MICROKERNEL_SRCS} APPEND_STRING PROPERTY COMPILE_FLAGS " -march=armv6 -mfpu=vfp -munaligned-access ")
  SET_PROPERTY(SOURCE ${PROD_ARMSIMD32_MICROKERNEL_SRCS} APPEND_STRING PROPERTY COMPILE_FLAGS " -march=armv6 -mfpu=vfp -munaligned-access ")

The types come from the arm header #include <arm_acle.h>

/* 8.5.5 Packing and unpacking */
#if defined(__ARM_FEATURE_SIMD32) && __ARM_FEATURE_SIMD32
typedef int32_t int8x4_t;
typedef int32_t int16x2_t;
typedef uint32_t uint8x4_t;
typedef uint32_t uint16x2_t;

Can you confirm the build system and compiler you used and that -march=armv6 is used on qs8-qc8w-igemm-2x2c4-minmax-fp32-armsimd32.c

These kernels are meant for Cortex M series that dont have Neon
For aarch32 builds that do have Neon, such as Raspberry Pi, the linux builds should work, but no script is provided

[candcv]

@fbarchard Thank you for your help.
Why this new version not provide the script for ARMv7 (with NEON) on Linux?

[fbarchard]

There is an armv7 script for android. When I tried it with NDK 21 it had a build error against I8MM due to an old version of clang being used, so I made cmake check the clang version and disable it.

Are you using scripts/build-local.sh ?