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<div class="content">
<h3 style="margin-top: 20px; margin-bottom: 10px;">
Matthew Pickering pushed to branch wip/iface-sharing-tyconapp at <a href="https://gitlab.haskell.org/ghc/ghc">Glasgow Haskell Compiler / GHC</a>
</h3>
<h4 style="margin-top: 10px; margin-bottom: 10px;">
Commits:
</h4>
<ul>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/68d406f8e1a96ec7fb92fa0b9acfa1692f181871">68d406f8</a></strong>
<div>
<span> by Fendor </span> <i> at 2024-04-10T10:11:27+02:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: var(--default-mono-font, "GitLab Mono"),"JetBrains Mono","Menlo","DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Refactor the Binary serialisation interface
The end goal is to dynamically add deduplication tables for `ModIface`
interface serialisation.
We identify two main points of interest that make this difficult:
1. UserData hardcodes what `Binary` instances can have deduplication
tables. Moreover, it heavily uses partial functions.
2. GHC.Iface.Binary hardcodes the deduplication tables for 'Name' and
'FastString', making it difficult to add more deduplication.
Instead of having a single `UserData` record with fields for all the
types that can have deduplication tables, we allow to provide custom
serialisers for any `Typeable`.
These are wrapped in existentials and stored in a `Map` indexed by their
respective `TypeRep`.
The `Binary` instance of the type to deduplicate still needs to
explicitly look up the decoder via `findUserDataReader` and
`findUserDataWriter`, which is no worse than the status-quo.
`Map` was chosen as microbenchmarks indicate it is the fastest for a
small number of keys (< 10).
To generalise the deduplication table serialisation mechanism, we
introduce the types `ReaderTable` and `WriterTable` which provide a
simple interface that is sufficient to implement a general purpose
deduplication mechanism for `writeBinIface` and `readBinIface`.
This allows us to provide a list of deduplication tables for
serialisation that can be extended more easily, for example for
`IfaceTyCon`, see the issue https://gitlab.haskell.org/ghc/ghc/-/issues/24540
for more motivation.
In addition to ths refactoring, we split `UserData` into `ReaderUserData`
and `WriterUserData`, to avoid partial functions.
Bump haddock submodule to accomodate for `UserData` split.
-------------------------
Metric Increase:
T21839c
-------------------------
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/026372f78d3a762a46e7135d869092062e7c3b20">026372f7</a></strong>
<div>
<span> by Fendor </span> <i> at 2024-04-10T10:11:27+02:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: var(--default-mono-font, "GitLab Mono"),"JetBrains Mono","Menlo","DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Split `BinHandle` into `ReadBinHandle` and `WriteBinHandle`
A `BinHandle` contains too much information for reading data.
For example, it needs to keep a `FastMutInt` and a `IORef BinData`,
when the non-mutable variants would suffice.
Additionally, this change has the benefit that anyone can immediately
tell whether the `BinHandle` is used for reading or writing.
Bump haddock submodule BinHandle split.
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/12a3a5d5f492a980eb9a76e2282905e282dc2222">12a3a5d5</a></strong>
<div>
<span> by Matthew Pickering </span> <i> at 2024-04-10T10:44:28+02:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: var(--default-mono-font, "GitLab Mono"),"JetBrains Mono","Menlo","DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Add deduplication table for `IfaceType`
The type `IfaceType` is a highly redundant, tree-like data structure.
While benchmarking, we realised that the high redundancy of `IfaceType`
causes high memory consumption in GHCi sessions.
We fix this by adding a deduplication table to the serialisation of
`ModIface`, similar to how we deduplicate `Name`s and `FastString`s.
When reading the interface file back, the table allows us to automatically
share identical values of `IfaceType`.
This deduplication has the beneficial side effect to additionally reduce
the size of the on-disk interface files tremendously. On the agda code
base, we reduce the size from 28 MB to 16 MB. When `-fwrite-simplified-core`
is enabled, we reduce the size from 112 MB to 22 MB.
We have to add an `Ord` instance to `IfaceType` in order to store it
efficiently for look up operations. This is mostly straightforward, we
change occurrences of `FastString` with `LexicalFastString` and add a
newtype definition for `IfLclName = LexicalFastString`.
Bump haddock submodule for `IfLclName` newtype changes.
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/4ed1ed633046150c772ffd0ccd2f7fd5fbba91c3">4ed1ed63</a></strong>
<div>
<span> by Fendor </span> <i> at 2024-04-10T10:44:30+02:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: var(--default-mono-font, "GitLab Mono"),"JetBrains Mono","Menlo","DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Add IfaceType deduplication table to .hie serialisation
Refactor .hie file serialisation to use the same infrastrucutre as
`putWithTables`.
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/c4a518b41ab6e205b113792c162a54c63ff8b633">c4a518b4</a></strong>
<div>
<span> by Matthew Pickering </span> <i> at 2024-04-10T10:44:30+02:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: var(--default-mono-font, "GitLab Mono"),"JetBrains Mono","Menlo","DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>WIP: TrieMap for IfaceType
Bump haddock submodule
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/829f88c9c22a96d48e121b4769924c7a6ef63e28">829f88c9</a></strong>
<div>
<span> by Fendor </span> <i> at 2024-04-10T11:58:08+02:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: var(--default-mono-font, "GitLab Mono"),"JetBrains Mono","Menlo","DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>WIP: CI results for Data.Map deduplication
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/21c669026729c847a25cded73398ecaee4951d84">21c66902</a></strong>
<div>
<span> by Matthew Pickering </span> <i> at 2024-04-10T11:12:09+01:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: var(--default-mono-font, "GitLab Mono"),"JetBrains Mono","Menlo","DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Add some tests to check for size of interface files when serialising
various types
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/aa5cd6305545e33fc255a8f669aad72907cdec41">aa5cd630</a></strong>
<div>
<span> by Matthew Pickering </span> <i> at 2024-04-10T11:12:09+01:00 </i>
</div>
<pre class="commit-message" style='white-space: pre-wrap; display: block; font-size: 14px; color: #333238; position: relative; font-family: var(--default-mono-font, "GitLab Mono"),"JetBrains Mono","Menlo","DejaVu Sans Mono","Liberation Mono","Consolas","Ubuntu Mono","Courier New","andale mono","lucida console",monospace; word-break: break-all; word-wrap: break-word; background-color: #fbfafd; border-radius: 2px; margin: 0; padding: 8px 12px; border: 1px solid #dcdcde;'>Only share IfaceTyConApp
</pre>
</li>
</ul>
<h4 style="margin-top: 10px; margin-bottom: 10px;">
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<a href="#640612f2fdc707ac7ee74f4165a7b86f38aa6249">
compiler/GHC/Core/Map/Expr.hs
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<a href="#578c7c3857d66d963736ff6742f3433a0e8d01b7">
compiler/GHC/Core/TyCo/Rep.hs
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compiler/GHC/CoreToIface.hs
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compiler/GHC/Data/FastString.hs
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compiler/GHC/Data/TrieMap.hs
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compiler/GHC/Iface/Binary.hs
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compiler/GHC/Iface/Decl.hs
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compiler/GHC/Iface/Env.hs
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compiler/GHC/Iface/Ext/Binary.hs
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compiler/GHC/Iface/Ext/Fields.hs
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compiler/GHC/Iface/Ext/Utils.hs
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compiler/GHC/Iface/Recomp.hs
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compiler/GHC/Iface/Recomp/Binary.hs
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compiler/GHC/Iface/Recomp/Flags.hs
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compiler/GHC/Iface/Syntax.hs
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compiler/GHC/Iface/Type.hs
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compiler/GHC/IfaceToCore.hs
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compiler/GHC/Stg/CSE.hs
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compiler/GHC/StgToJS/Object.hs
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compiler/GHC/Types/Basic.hs
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compiler/GHC/Types/FieldLabel.hs
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compiler/GHC/Types/Name.hs
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compiler/GHC/Types/Var.hs
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compiler/GHC/Utils/Binary.hs
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compiler/GHC/Utils/Binary/Typeable.hs
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compiler/Language/Haskell/Syntax/Type.hs
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compiler/Language/Haskell/Syntax/Type.hs-boot
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compiler/ghc.cabal.in
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testsuite/tests/iface/IfaceSharingFastString.hs
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The diff was not included because it is too large.
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