Faster Compile Times and Better Performance: Bringing Just-in-Time Compilation to C++

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" summary

ClangJIT implements deferred instantiation by embedding serialized AST/modules and compiler state in object files, letting the program supply non‑type template values at runtime (types currently resolved from strings) and instantiate on demand without filesystem access. Ahead‑of‑time builds that compile three specializations take ~7s versus the JIT image build ~1s; runtime compilation of small template cases is milliseconds while runtime performance matches AOT and GPU kernels see up to 100x speedups for tiny matrices. It works but pays a first‑use compilation cost and has current limits around types, error reporting and resource management; CUDA support is included.

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" chapters (35)

1. 0:00Introduction
2. 3:15Purpose
3. 4:02Use Case
4. 4:33Program Productivity
5. 6:47JustinTime Compilation
6. 7:40The Problem
7. 8:10What does this mean
8. 9:41Can you construct a JIT for C
9. 11:50Specialization and generic programming
10. 12:40JustinTime compilation and generic programming
11. 13:51Cost of compilation
12. 15:12Requirements
13. 16:45HelloWorld
14. 18:12More complicated example
15. 19:23Semantics
16. 20:43Limitations
17. 21:37What happens when you compile
18. 22:32Metadata
19. 24:00Runtime
20. 25:24Benchmarks
21. 26:51Compile Time
22. 28:56Performance Comparison
23. 32:45Using JustinTime Compilation
24. 33:13Simulation Code Example
25. 36:34Costs
26. 38:06Second example
27. 38:58Benchmark
28. 39:32How to hook CTRE
29. 41:51Compiler Performance
30. 42:55The Future
31. 45:13Challenges Design Options
32. 46:40Other Concerns
33. 48:12Committee Feedback
34. 50:26Underlying Question
35. 51:03Conclusions

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