On Fri, Apr 26, 2024 at 10:11 AM Dave Thaler <dthaler1968@xxxxxxxxxxxxxx> wrote: > > This patch elaborates on the use of PC by expanding the PC acronym, > explaining the units, and the relative position to which the offset > applies. > > Signed-off-by: Dave Thaler <dthaler1968@xxxxxxxxxxxxxx> > --- > Documentation/bpf/standardization/instruction-set.rst | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/Documentation/bpf/standardization/instruction-set.rst b/Documentation/bpf/standardization/instruction-set.rst > index b44bdacd0..5592620cf 100644 > --- a/Documentation/bpf/standardization/instruction-set.rst > +++ b/Documentation/bpf/standardization/instruction-set.rst > @@ -469,6 +469,11 @@ JSLT 0xc any PC += offset if dst < src signed > JSLE 0xd any PC += offset if dst <= src signed > ======== ===== ======= ================================= =================================================== > > +where 'PC' denotes the program counter, and the offset to increment by > +is in units of 64-bit instructions relative to the instruction following > +the jump instruction. Thus 'PC += 1' results in the next instruction > +to execute being two 64-bit instructions later. The last part is confusing. "two 64-bit instructions later" I'm struggling to understand that. Maybe say that 'PC += 1' skips execution of the next insn?
