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Subject[patch 00/12] Immediate Values
Hi Ingo,

Here is an updated version of the immediate values, applying to current tip.

[impact: data-cache optimization]

The main benefit of this infrastructure is to encode read-often variables into
the instruction stream. It can benefit to tracepoints by replacing the memory
load by an immediate value instruction. There is still room for improvement
through: an effort to provide static jump patching is ongoing, involving the
kernel and gcc communities.

Even then, the immediate values have their niche: when a value (rather than a
branch selection) is read often on fast-paths, the immediate value
infrastructure can encode these in the instruction stream without any d-cache
cost.

Two sample users are provided: prof_on from the scheduler code and tracepoints.
Feel free to merge/drop any of these.

Thanks,

Mathieu

--
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68


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