llvm / llvm/circt

Late pipeline passes should not be doing type coercion.

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bug
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C++
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Description

Please do not do this. The goal is to remove this logic entirely and stop duplicating it in every pass. We should never get to this point in the pass with the register reset value being the wrong type for the register. That should be fixed in parsing.

_Originally posted by @darthscsi in https://github.com/llvm/circt/pull/4788#pullrequestreview-1338110528_

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Research direction

Start by locating the late pipeline passes that perform register reset-value type coercion and the parsing path that supplies those values. Remove the duplicated late-pass coercion and verify that parsing guarantees the reset value has the register's type before any pass runs.

Written by the indexing model from the issue text.

Assessment

Tech stack
cpp
Domain
compilers
Issue type
Refactor
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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