Hi David.
> New instructions have been added over time to the eBPF ISA, but
> previously there has been no good method to select which version to
> target in GCC.
>
> This patch adds the following options to the BPF backend:
>
> -mcpu={v1, v2, v3}
> Select which version of the eBPF ISA to target. This enables or
> disables generation of certain instructions. The default is v3.
>
> -mjmpext
> Enable extra conditional branch instructions.
> Enabled for CPU v2 and above.
>
> -mjmp32
> Enable 32-bit jump/branch instructions.
> Enabled for CPU v3 and above.
>
> -malu32
> Enable 32-bit ALU instructions.
> Enabled for CPU v3 and above.
>
> Negative versions of -mjmpext, -mjmp32, and -malu32 options are also
> supported.
The series is OK.
Thanks!
>
> David Faust (3):
> bpf: add -mcpu and related feature options
> bpf testsuite: add tests for new feature options
> doc: document BPF -mcpu and related options
>
> gcc/config/bpf/bpf-opts.h | 7 ++++
> gcc/config/bpf/bpf-protos.h | 1 +
> gcc/config/bpf/bpf.c | 41 ++++++++++++++++++++
> gcc/config/bpf/bpf.md | 44 +++++++++++----------
> gcc/config/bpf/bpf.opt | 29 ++++++++++++++
> gcc/doc/invoke.texi | 39 ++++++++++++++++++-
> gcc/testsuite/gcc.target/bpf/alu-1.c | 56 +++++++++++++++++++++++++++
> gcc/testsuite/gcc.target/bpf/jmp-1.c | 57 ++++++++++++++++++++++++++++
> 8 files changed, 253 insertions(+), 21 deletions(-)
> create mode 100644 gcc/testsuite/gcc.target/bpf/alu-1.c
> create mode 100644 gcc/testsuite/gcc.target/bpf/jmp-1.c
