| =========================================================================== | |
| Building a JIT: Extreme Laziness - Using Compile Callbacks to JIT from ASTs | |
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| .. contents:: | |
| :local: | |
| **This tutorial is under active development. It is incomplete and details may | |
| change frequently.** Nonetheless we invite you to try it out as it stands, and | |
| we welcome any feedback. | |
| Chapter 4 Introduction | |
| ====================== | |
| Welcome to Chapter 4 of the "Building an ORC-based JIT in LLVM" tutorial. This | |
| chapter introduces the Compile Callbacks and Indirect Stubs APIs and shows how | |
| they can be used to replace the CompileOnDemand layer from | |
| `Chapter 3 <BuildingAJIT3.html>`_ with a custom lazy-JITing scheme that JITs | |
| directly from Kaleidoscope ASTs. | |
| **To be done:** | |
| **(1) Describe the drawbacks of JITing from IR (have to compile to IR first, | |
| which reduces the benefits of laziness).** | |
| **(2) Describe CompileCallbackManagers and IndirectStubManagers in detail.** | |
| **(3) Run through the implementation of addFunctionAST.** | |
| Full Code Listing | |
| ================= | |
| Here is the complete code listing for our running example that JITs lazily from | |
| Kaleidoscope ASTS. To build this example, use: | |
| .. code-block:: bash | |
| # Compile | |
| clang++ -g toy.cpp `llvm-config --cxxflags --ldflags --system-libs --libs core orcjit native` -O3 -o toy | |
| # Run | |
| ./toy | |
| Here is the code: | |
| .. literalinclude:: ../../examples/Kaleidoscope/BuildingAJIT/Chapter4/KaleidoscopeJIT.h | |
| :language: c++ | |
| `Next: Remote-JITing -- Process-isolation and laziness-at-a-distance <BuildingAJIT5.html>`_ |