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42 lines
2.0 KiB
Markdown
42 lines
2.0 KiB
Markdown
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## Linker Script Generator
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Contains code that implements linker script generation, `ldgen`. For more information about the feature,
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see `docs/en/api-guides/linker-script-generation.rst`.
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### Source Files
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The following are the source files in the directory:
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- `ldgen.py` - Python executable that gets called during build.
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- `entity.py` - contains classes related to entities (library, object, symbol or combination of the above) with mappable input sections.
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- `fragments.py` - contains classes for parsing the different types of fragments in linker fragment files.
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- `generation.py` - contains bulk of the logic used to process fragments into output commands.
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- `sdkconfig.py` - used for evaluating conditionals in fragment files.
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- `linker_script.py` - augments the input linker script template with output commands from generation process to produce the output linker script.
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- `output_commands.py` - contains classes that represent the output commands in the output linker script.
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- `ldgen_common.py` - contains miscellaneous utilities/definitions that can be used in the files mentioned above.
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### Tests
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Unit tests are in the `test` directory. These tests are run as part of CI in the job `test_ldgen_on_host`.
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There is also a test app for `ldgen` in `tools/test_apps/build_system/ldgen_test`.
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### Build System
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Linker script generation is a part of the build process. The build scripts `tools/cmake/ldgen.cmake`
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and `make/ldgen.mk` contain the build-system-side implementation for CMake and Make, respectively.
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### Basic Flow
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The build system invokes `ldgen.py`, passing some information from the build.
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The linker fragment files are parsed by `fragments.py`, evaluating conditional expressions
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with `sdkconfig.py`.
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From the parsed fragments, `generation.py` generates output commands defined in `output_commands.py`,
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with some help from `entity.py`.
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`linker_script.py` writes the output linker script, replacing markers with output commands generated.
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More details about the implementation are in the respective source files.
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