System-level compilation of parallel real-time systems

Our work is at the frontier between real-time scheduling and
compilation. Our objective is to build parallel software that
respects hard real-time requirements.

Historically, the construction of real-time systems relied on
the use of very abstract models – known as task models – of both
software and the execution platform. Building a task model involves
high abstraction overheads and is seldom, if ever, done soundly.
Once the task model is built, its relatively small size enabled
the use of “exact” constraint solving techniques.
But this solution does not scale to the size and complexity of
next-generation embedded software and hardware.

Based on previous work in the AOSTE team, our objective was to
apply a compilation-like approach to this implementation problem
using strong hypotheses on the capabilities of the execution platform
and on the form of input specifications.
We rely on low-complexity allocation and scheduling heuristics
based on list scheduling. This low complexity allows the use
of precise models of the platform and executing software, detailing
aspects such as synchronization, memory coherency, and timing.
Code synthesis covers all aspects of code generation: allocation,
scheduling, the construction of thread code, and the construction
of linker scripts.
The resulting compiler carefully integrates
multiple tools – dataflow compiler, mapping and code generation
tool, C compiler and linker, static analysis tool.

When? January 22, 2019 – 13:30
Where? IRIT, room 001