Compiler Front End Panel Robert Geva Speaking for myself, working as a parallel programming architect Intel Compilers and Languages 2018/12/8

1. Language Support for Parallelism Data Parallelism Integration of Firetown (Ct) and RapidMind Array notation for C/C++ Semantically mandating data parallelism Task Parallelism Integration of Cilk++ and TBB A Cilk++ program is serialize- able Well defined points where execution becomes async Minimal addition to baseline language Defense against data races Safe, friendly parallel programming is achievable 12/8/2018

2. Performance Provided by System SW Firetown will use JIT compilation Adapt to HW, vector ISA Profile guided optimization – take the data into account TBB, Cilk rely on the programmer to write small units of work, units of scheduling (over decomposition) User mode work stealing scheduler provides dynamic load balancing Research project: CPU performance counters made available to a JIT compiler, allow dynamic re-optimizations Working to move performance responsibility from the programmer to system SW 12/8/2018

4. Tools Discovery tools Intel Parallel Advisor: read the source code Guide though elimination of potential data races Recommend opportunities to introduce parallelism based on program loop structure, targeting outer loops Guided Auto Parallelism: Programmer writes serial code Compiler attempts to auto parallelize, vectorize Provide guidance on how to restructure the serial code to remove semantic obstacles Biggest challenge: tools to help write a parallel program 12/8/2018

5. 3’rd party, pre compiled libraries IA SW echo system has a strong force of gravity Any solution, especially in native programming, must be compatible with existing, non recompiled SW As well as with 3’rd party tools Backward compatibility is unquestioned 12/8/2018

3. Heterogeneous Targets Target: CPU + LRB A Solution: CELO Multi core big core IA Many core IA Separate physical memories Different ISA extensions Different OSes Native, C/C++ A single source code base fed into a single compiler, generates a program that utilizes both core types TBB, Cilk++ model for parallelism MYO – system SW layer for data synchronization across the PCIe buss Minimal (<5 keywords) language extension to express what code executes on which core type Heterogeneous target is programmable with existing languages and existing methodologies. 12/8/2018