Commit ee159bdb authored by Dave Thaler's avatar Dave Thaler Committed by Alexei Starovoitov
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bpf, docs: Add Clang note about BPF_ALU 



Add Clang note about BPF_ALU.

Signed-off-by: default avatarDave Thaler <dthaler@microsoft.com>
Link: https://lore.kernel.org/r/20220927185958.14995-4-dthaler1968@googlemail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 6c7aaffb

Documentation/bpf/clang-notes.rst

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@@ -14,6 +14,12 @@ Clang defined "CPU" versions, where a CPU version of 3 corresponds to the curren 


Clang can select the eBPF ISA version using ``-mcpu=v3`` for example to select version 3.



Arithmetic instructions

=======================



For CPU versions prior to 3, Clang v7.0 and later can enable ``BPF_ALU`` support with

``-Xclang -target-feature -Xclang +alu32``.  In CPU version 3, support is automatically included.



Atomic operations

=================