This is an archive of the discontinued LLVM Phabricator instance.

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	.. code-block:: shell			.. code-block:: shell

	$ opt -passes='function(require<my-function-analysis>),my-module-pass' /tmp/a.ll -S			$ opt -passes='function(require<my-function-analysis>),my-module-pass' /tmp/a.ll -S

	Status of the New and Legacy Pass Managers			Status of the New and Legacy Pass Managers
	==========================================			==========================================

	LLVM currently contains two pass managers, the legacy PM and the new PM. The			LLVM currently contains two pass managers, the legacy PM and the new PM. The
	optimization pipeline (aka the middle-end) works with both the legacy PM and			optimization pipeline (aka the middle-end) uses the new PM, whereas the backend
	the new PM, whereas the backend target-dependent code generation only works			target-dependent code generation uses the legacy PM.
	with the legacy PM.
				The legacy PM somewhat works with the optimization pipeline, but this is
	For the optimization pipeline, the new PM is the default PM. Using the legacy PM			deprecated and there are ongoing efforts to remove its usage.
	for the optimization pipeline is deprecated and there are ongoing efforts to
	remove its usage.

	Some IR passes are considered part of the backend codegen pipeline even if			Some IR passes are considered part of the backend codegen pipeline even if
	they are LLVM IR passes (whereas all MIR passes are codegen passes). This			they are LLVM IR passes (whereas all MIR passes are codegen passes). This
	includes anything added via ``TargetPassConfig`` hooks, e.g.			includes anything added via ``TargetPassConfig`` hooks, e.g.
	``TargetPassConfig::addCodeGenPrepare()``.			``TargetPassConfig::addCodeGenPrepare()``.

	The ``TargetMachine::adjustPassManager()`` function that was used to extend a			The ``TargetMachine::adjustPassManager()`` function that was used to extend a
	legacy PM with passes on a per target basis has been removed. It was mainly			legacy PM with passes on a per target basis has been removed. It was mainly
	used from opt, but since support for using the default pipelines has been			used from opt, but since support for using the default pipelines has been
	removed in opt the function isn't needed any longer. In the new PM such			removed in opt the function isn't needed any longer. In the new PM such
	adjustments are done by using ``TargetMachine::registerPassBuilderCallbacks()``.			adjustments are done by using ``TargetMachine::registerPassBuilderCallbacks()``.

	Currently there are efforts to make the codegen pipeline work with the new			Currently there are efforts to make the codegen pipeline work with the new
	PM.			PM.

This is an archive of the discontinued LLVM Phabricator instance.

[docs][NewPM] Clarify more status of legacy PM + optimization pipelineClosedPublic

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llvm/docs/NewPassManager.rst

[docs][NewPM] Clarify more status of legacy PM + optimization pipeline
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