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