Rather than checking the binutils version number, which can lead to unnecessary disabling of AVX512 if fixes have been backported to distro versions, we can instead check the output of "as" from binutils to see if it is correct.
The check in the script uses the minimal assembly reproduction code posted to the public bug tracker for gcc/binutils for those issues [1]. If the binutils bug is present, the instruction parameters - specifically the displacement parameter - will be different in the disassembled output compared to the input. Therefore the check involves assembling a single instruction and disassembling it again, checking that the two match. [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90028 Signed-off-by: Bruce Richardson <bruce.richard...@intel.com> Tested-by: Harry van Haaren <harry.van.haa...@intel.com> --- V3: - Use mktemp to create a temporary file rather than place object file in build folder. Use trap to ensure temp file deletion on exit. V2: - Renamed "as_ok" variable to "binutils_ok" for readability - Removed one test case from the script because even though two DPDK bugs were filed, the one binutils bug is the root cause, and a single commit fixes them both - Changed message() to warning() in the printout --- buildtools/binutils-avx512-check.sh | 16 ++++++++++++++++ buildtools/meson.build | 3 +-- config/x86/meson.build | 10 +++------- meson.build | 5 ++++- 4 files changed, 24 insertions(+), 10 deletions(-) create mode 100755 buildtools/binutils-avx512-check.sh diff --git a/buildtools/binutils-avx512-check.sh b/buildtools/binutils-avx512-check.sh new file mode 100755 index 000000000..a7e068140 --- /dev/null +++ b/buildtools/binutils-avx512-check.sh @@ -0,0 +1,16 @@ +#! /bin/sh +# SPDX-License-Identifier: BSD-3-Clause +# Copyright(c) 2020 Intel Corporation + +AS=${AS:-as} +OBJFILE=$(mktemp -t dpdk.binutils-check.XXXXXX.o) +trap 'rm -f "$OBJFILE"' EXIT +# from https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90028 +GATHER_PARAMS='0x8(,%ymm1,1),%ymm0{%k2}' + +# assemble vpgather to file and similarly check +echo "vpgatherqq $GATHER_PARAMS" | $AS --64 -o $OBJFILE - +objdump -d --no-show-raw-insn $OBJFILE | grep -q $GATHER_PARAMS || { + echo "vpgatherqq displacement error with as" + exit 1 +} diff --git a/buildtools/meson.build b/buildtools/meson.build index f9d2fdf74..cf0048f3c 100644 --- a/buildtools/meson.build +++ b/buildtools/meson.build @@ -1,13 +1,12 @@ # SPDX-License-Identifier: BSD-3-Clause # Copyright(c) 2017-2019 Intel Corporation -subdir('pmdinfogen') - pkgconf = find_program('pkg-config', 'pkgconf', required: false) pmdinfo = find_program('gen-pmdinfo-cfile.sh') list_dir_globs = find_program('list-dir-globs.py') check_symbols = find_program('check-symbols.sh') ldflags_ibverbs_static = find_program('options-ibverbs-static.sh') +binutils_avx512_check = find_program('binutils-avx512-check.sh') # set up map-to-win script using python, either built-in or external python3 = import('python').find_installation(required: false) diff --git a/config/x86/meson.build b/config/x86/meson.build index adc857ba2..6ec020ef6 100644 --- a/config/x86/meson.build +++ b/config/x86/meson.build @@ -3,14 +3,10 @@ # get binutils version for the workaround of Bug 97 if not is_windows - ldver = run_command('ld', '-v').stdout().strip() - if ldver.contains('2.30') and cc.has_argument('-mno-avx512f') + binutils_ok = run_command(binutils_avx512_check) + if binutils_ok.returncode() != 0 and cc.has_argument('-mno-avx512f') machine_args += '-mno-avx512f' - message('Binutils 2.30 detected, disabling AVX512 support as workaround for bug #97') - endif - if ldver.contains('2.31') and cc.has_argument('-mno-avx512f') - machine_args += '-mno-avx512f' - message('Binutils 2.31 detected, disabling AVX512 support as workaround for bug #249') + warning('Binutils error with AVX512 assembly, disabling AVX512 support') endif endif diff --git a/meson.build b/meson.build index d21adfd30..7c336df6d 100644 --- a/meson.build +++ b/meson.build @@ -40,10 +40,13 @@ global_inc = include_directories('.', 'config', 'lib/librte_eal/@0@/include'.format(host_machine.system()), 'lib/librte_eal/@0@/include'.format(arch_subdir), ) + +# do configuration and get tool paths +subdir('buildtools') subdir('config') # build libs and drivers -subdir('buildtools') +subdir('buildtools/pmdinfogen') subdir('lib') subdir('drivers') -- 2.25.1
