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<div class="content">

<h3 style="margin-top: 20px; margin-bottom: 10px;">
Hannes Siebenhandl pushed to branch wip/fendor/iface-sharing 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/03084bcc97666b45c94b4aedc8bbddb136152390">03084bcc</a></strong>
<div>
<span> by Matthew Pickering </span> <i> at 2024-04-15T11:52:42+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`.

We also add IfaceType deduplication table to .hie serialisation and
refactor .hie file serialisation to use the same infrastrucutre as
`putWithTables`.

Bump haddock submodule for `IfLclName` newtype changes.
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/d64cfe21eebb64db08da04d5d2bd613cc737f5e8">d64cfe21</a></strong>
<div>
<span> by Matthew Pickering </span> <i> at 2024-04-15T11:54:14+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 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/5610aa869959f8d7980329dddc8ba3fd5698191c">5610aa86</a></strong>
<div>
<span> by Matthew Pickering </span> <i> at 2024-04-15T11:54:14+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/2a19c5c55a5dceea9dbcef696c2b638ad788a716">2a19c5c5</a></strong>
<div>
<span> by Fendor </span> <i> at 2024-04-15T11:54:15+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/292f6f81ee65f0972b9bc1687b0e2fcd68e39025">292f6f81</a></strong>
<div>
<span> by Matthew Pickering </span> <i> at 2024-04-15T11:54:15+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;'>Only share IfaceTyConApp
</pre>
</li>
<li>
<strong style="font-weight: bold;"><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/c5077818d5893f5ab5e58bd06306faa59b54c1c5">c5077818</a></strong>
<div>
<span> by Fendor </span> <i> at 2024-04-15T11:56:54+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;'>Share duplicated values in ModIface after generation

This helps keeping down the peak memory usage while compiling in
`--make` mode.
</pre>
</li>
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The diff was not included because it is too large.
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