[ovs-git] [openvswitch/ovs] 0f89f4: dpif-netdev/avx512: avoid compiling avx512 code if...

[istokes]

  Branch: refs/heads/branch-2.14
  Home:   https://github.com/openvswitch/ovs
  Commit: 0f89f4e2d192cfc68f6040e8b0dd7bcf9a9fe296
      https://github.com/openvswitch/ovs/commit/0f89f4e2d192cfc68f6040e8b0dd7bcf9a9fe296
  Author: Harry van Haaren <harry.van.haaren at intel.com>
  Date:   2020-08-05 (Wed, 05 Aug 2020)

  Changed paths:
    M lib/automake.mk

  Log Message:
  -----------
  dpif-netdev/avx512: avoid compiling avx512 code if binutils check fails

This commit avoids compiling and linking of avx512 code into the
vswitch_la library if the binutils check fails. This avoids compiling
code into OVS that will not be executed due to binutils issue.

Signed-off-by: Harry van Haaren <harry.van.haaren at intel.com>
Signed-off-by: Ian Stokes <ian.stokes at intel.com>


  Commit: 0486099b885b3b2b4f07ce47850cfc1bd4ebb35a
      https://github.com/openvswitch/ovs/commit/0486099b885b3b2b4f07ce47850cfc1bd4ebb35a
  Author: Harry van Haaren <harry.van.haaren at intel.com>
  Date:   2020-08-05 (Wed, 05 Aug 2020)

  Changed paths:
    M lib/automake.mk

  Log Message:
  -----------
  dpif-netdev/avx512: add -fPIC flag to enable shared builds

In certain scenarios with OVS built with --enable-shared and
DPDK enabled as shared build too, Position Independant Code
is required to link the avx512.a file into the relocatable .so
that it must be linked into.

Signed-off-by: Harry van Haaren <harry.van.haaren at intel.com>
Signed-off-by: Ian Stokes <ian.stokes at intel.com>


  Commit: d73e041859bf5f2770aca3c26b15ce2898b0639b
      https://github.com/openvswitch/ovs/commit/d73e041859bf5f2770aca3c26b15ce2898b0639b
  Author: Harry van Haaren <harry.van.haaren at intel.com>
  Date:   2020-08-05 (Wed, 05 Aug 2020)

  Changed paths:
    M m4/openvswitch.m4

  Log Message:
  -----------
  configure: explicitly disable avx512 if bintuils check fails

This commit explicitly disables avx512f if the binutils assembler
check fails to correctly assemble its input.

Without this fix, there is a possibility that users can see undefined
behaviour when compiling with -march=native on a CPU which supports
avx512 and with a buggy binutils version (v2.30 and 2.31), without a
backported fix, if the compiler's vectorizing optimizations convert
scalar code to avx512 instructions.

Signed-off-by: Harry van Haaren <harry.van.haaren at intel.com>
Signed-off-by: Ian Stokes <ian.stokes at intel.com>


Compare: https://github.com/openvswitch/ovs/compare/c1d7120c61ec...d73e041859bf