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<h3>
Andreas Klebinger pushed to branch wip/andreask/refactor_cmm_weights
at <a href="https://gitlab.haskell.org/ghc/ghc">Glasgow Haskell Compiler / GHC</a>
</h3>
<h4>
Commits:
</h4>
<ul>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/40a85563a46c682eaab5fdf970f7c46afca78cb3">40a85563</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-04-03T18:26:19+03:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Revert accidental change in 9462452
[ci skip]
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/bd75e5da0f1f05f107325733b570bf28b379d2f2">bd75e5da</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-04T07:07:58-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Enable ImpredicativeTypes internally when typechecking selector bindings
This is necessary for certain record selectors with higher-rank
types, such as the examples in #18005. See
`Note [Impredicative record selectors]` in `TcTyDecls`.
Fixes #18005.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/dcfe29c8520244764146c7a5f336be1f9700db6c">dcfe29c8</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-04-06T13:16:08-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Don't override proc CafInfos in ticky builds
Fixes #17947
When we have a ticky label for a proc, IdLabels for the ticky counter
and proc entry share the same Name. This caused overriding proc CafInfos
with the ticky CafInfos (i.e. NoCafRefs) during SRT analysis.
We now ignore the ticky labels when building SRTMaps. This makes sense
because:
- When building the current module they don't need to be in SRTMaps as
they're initialized as non-CAFFY (see mkRednCountsLabel), so they
don't take part in the dependency analysis and they're never added to
SRTs.
(Reminder: a "dependency" in the SRT analysis is a CAFFY dependency,
non-CAFFY uses are not considered as dependencies for the algorithm)
- They don't appear in the interfaces as they're not exported, so it
doesn't matter for cross-module concerns whether they're in the SRTMap
or not.
See also the new Note [Ticky labels in SRT analysis].
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/cec2c71fe91c88649628c6e83416533b816b86a5">cec2c71f</a></strong>
<div>
<span>by Simon Peyton Jones</span>
<i>at 2020-04-06T13:16:44-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix an tricky specialiser loop
Issue #17151 was a very tricky example of a bug in which the
specialiser accidentally constructs a recurive dictionary,
so that everything turns into bottom.
I have fixed variants of this bug at least twice before:
see Note [Avoiding loops]. It was a bit of a struggle
to isolate the problem, greatly aided by the work that
Alexey Kuleshevich did in distilling a test case.
Once I'd understood the problem, it was not difficult to fix,
though it did lead me a bit of refactoring in specImports.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/e850d14ffbeea39ad386b1e888cd97375758d6d6">e850d14f</a></strong>
<div>
<span>by Simon Peyton Jones</span>
<i>at 2020-04-06T13:16:44-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Refactoring only
This refactors DictBinds into a data type rather than a pair.
No change in behaviour, just better code
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/f38e8d61f066c3064c600c352eebcd87f28d989a">f38e8d61</a></strong>
<div>
<span>by Daniel Gröber</span>
<i>at 2020-04-07T02:00:05-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: ProfHeap: Fix memory leak when not compiled with profiling
If we're doing heap profiling on an unprofiled executable we keep
allocating new space in initEra via nextEra on each profiler run but we
don't have a corresponding freeEra call.
We do free the last era in endHeapProfiling but previous eras will have
been overwritten by initEra and will never get free()ed.
Metric Decrease:
space_leak_001
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/bcd668593e1c9e00c5d9c72960b4833dd526cb9a">bcd66859</a></strong>
<div>
<span>by Sebastian Graf</span>
<i>at 2020-04-07T02:00:41-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Re-export GHC.Magic.noinline from base
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/3d2991f8b4c1b686323b2c9452ce845a60b8d94c">3d2991f8</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-07T18:36:09-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">simplifier: Kill off ufKeenessFactor
We used to have another factor, ufKeenessFactor, which would scale the
discounts before they were subtracted from the size. This was justified
with the following comment:
-- We multiple the raw discounts (args_discount and result_discount)
-- ty opt_UnfoldingKeenessFactor because the former have to do with
-- *size* whereas the discounts imply that there's some extra
-- *efficiency* to be gained (e.g. beta reductions, case reductions)
-- by inlining.
However, this is highly suspect since it means that we subtract a
*scaled* size from an absolute size, resulting in crazy (e.g. negative)
scores in some cases (#15304). We consequently killed off
ufKeenessFactor and bumped up the ufUseThreshold to compensate.
Adjustment of unfolding use threshold
=====================================
Since this removes a discount from our inlining heuristic, I revisited our
default choice of -funfolding-use-threshold to minimize the change in
overall inlining behavior. Specifically, I measured runtime allocations
and executable size of nofib and the testsuite performance tests built
using compilers (and core libraries) built with several values of
-funfolding-use-threshold.
This comes as a result of a quantitative comparison of testsuite
performance and code size as a function of ufUseThreshold, comparing
GHC trees using values of 50, 60, 70, 80, 90, and 100. The test set
consisted of nofib and the testsuite performance tests.
A full summary of these measurements are found in the description of
!2608
Comparing executable sizes (relative to the base commit) across all
nofib tests, we see that sizes are similar to the baseline:
gmean min max median
thresh
50 -6.36% -7.04% -4.82% -6.46%
60 -5.04% -5.97% -3.83% -5.11%
70 -2.90% -3.84% -2.31% -2.92%
80 -0.75% -2.16% -0.42% -0.73%
90 +0.24% -0.41% +0.55% +0.26%
100 +1.36% +0.80% +1.64% +1.37%
baseline +0.00% +0.00% +0.00% +0.00%
Likewise, looking at runtime allocations we see that 80 gives slightly
better optimisation than the baseline:
gmean min max median
thresh
50 +0.16% -0.16% +4.43% +0.00%
60 +0.09% -0.00% +3.10% +0.00%
70 +0.04% -0.09% +2.29% +0.00%
80 +0.02% -1.17% +2.29% +0.00%
90 -0.02% -2.59% +1.86% +0.00%
100 +0.00% -2.59% +7.51% -0.00%
baseline +0.00% +0.00% +0.00% +0.00%
Finally, I had to add a NOINLINE in T4306 to ensure that `upd` is
worker-wrappered as the test expects. This makes me wonder whether the
inlining heuristic is now too liberal as `upd` is quite a large
function. The same measure was taken in T12600.
Wall clock time compiling Cabal with -O0
thresh 50 60 70 80 90 100 baseline
build-Cabal 93.88 89.58 92.59 90.09 100.26 94.81 89.13
Also, this change happens to avoid the spurious test output in
`plugin-recomp-change` and `plugin-recomp-change-prof` (see #17308).
Metric Decrease:
hie002
T12234
T13035
T13719
T14683
T4801
T5631
T5642
T9020
T9872d
T9961
Metric Increase:
T12150
T12425
T13701
T14697
T15426
T1969
T3064
T5837
T6048
T9203
T9872a
T9872b
T9872c
T9872d
haddock.Cabal
haddock.base
haddock.compiler
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/255418da5d264fb2758bc70925adb2094f34adc3">255418da</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-07T18:36:49-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Modules: type-checker (#13009)
Update Haddock submodule
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/04b6cf947ea065a210a216cc91f918cc1660d430">04b6cf94</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-07T19:43:20-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Make NoExtCon fields strict
This changes every unused TTG extension constructor to be strict in
its field so that the pattern-match coverage checker is smart enough
any such constructors are unreachable in pattern matches. This lets
us remove nearly every use of `noExtCon` in the GHC API. The only
ones we cannot remove are ones underneath uses of `ghcPass`, but that
is only because GHC 8.8's and 8.10's coverage checkers weren't smart
enough to perform this kind of reasoning. GHC HEAD's coverage
checker, on the other hand, _is_ smart enough, so we guard these uses
of `noExtCon` with CPP for now.
Bumps the `haddock` submodule.
Fixes #17992.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/7802fa17a9a1a0f02fbf95170c13d7a9711a681e">7802fa17</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-08T16:43:44-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Handle promoted data constructors in typeToLHsType correctly
Instead of using `nlHsTyVar`, which hardcodes `NotPromoted`, have
`typeToLHsType` pick between `Promoted` and `NotPromoted` by checking
if a type constructor is promoted using `isPromotedDataCon`.
Fixes #18020.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/ce481361fc95405cfadcd8f930629381e80e7f84">ce481361</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-09T16:17:21-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">hadrian: Use --export-dynamic when linking iserv
As noticed in #17962, the make build system currently does this (see
3ce0e0ba) but the change was never ported to Hadrian.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/fa66f143a61f2285618c611a27c23815ca588299">fa66f143</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-09T16:17:21-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">iserv: Don't pass --export-dynamic on FreeBSD
This is definitely a hack but it's probably the best we can do for now.
Hadrian does the right thing here by passing --export-dynamic only to
the linker.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/390751768104cd3d2cb57e2037062916476ebd10">39075176</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-04-09T16:18:00-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix CNF handling in compacting GC
Fixes #17937
Previously compacting GC simply ignored CNFs. This is mostly fine as
most (see "What about small compacts?" below) CNF objects don't have
outgoing pointers, and are "large" (allocated in large blocks) and large
objects are not moved or compacted.
However if we do GC *during* sharing-preserving compaction then the CNF
will have a hash table mapping objects that have been moved to the CNF
to their location in the CNF, to be able to preserve sharing.
This case is handled in the copying collector, in `scavenge_compact`,
where we evacuate hash table entries and then rehash the table.
Compacting GC ignored this case.
We now visit CNFs in all generations when threading pointers to the
compacted heap and thread hash table keys. A visited CNF is added to the
list `nfdata_chain`. After compaction is done, we re-visit the CNFs in
that list and rehash the tables.
The overhead is minimal: the list is static in `Compact.c`, and link
field is added to `StgCompactNFData` closure. Programs that don't use
CNFs should not be affected.
To test this CNF tests are now also run in a new way 'compacting_gc',
which just passes `-c` to the RTS, enabling compacting GC for the oldest
generation. Before this patch the result would be:
Unexpected failures:
compact_gc.run compact_gc [bad exit code (139)] (compacting_gc)
compact_huge_array.run compact_huge_array [bad exit code (1)] (compacting_gc)
With this patch all tests pass. I can also pass `-c -DS` without any
failures.
What about small compacts? Small CNFs are still not handled by the
compacting GC. However so far I'm unable to write a test that triggers a
runtime panic ("update_fwd: unknown/strange object") by allocating a
small CNF in a compated heap. It's possible that I'm missing something
and it's not possible to have a small CNF.
NoFib Results:
--------------------------------------------------------------------------------
Program Size Allocs Instrs Reads Writes
--------------------------------------------------------------------------------
CS +0.1% 0.0% 0.0% +0.0% +0.0%
CSD +0.1% 0.0% 0.0% 0.0% 0.0%
FS +0.1% 0.0% 0.0% 0.0% 0.0%
S +0.1% 0.0% 0.0% 0.0% 0.0%
VS +0.1% 0.0% 0.0% 0.0% 0.0%
VSD +0.1% 0.0% +0.0% +0.0% -0.0%
VSM +0.1% 0.0% +0.0% -0.0% 0.0%
anna +0.0% 0.0% -0.0% -0.0% -0.0%
ansi +0.1% 0.0% +0.0% +0.0% +0.0%
atom +0.1% 0.0% +0.0% +0.0% +0.0%
awards +0.1% 0.0% +0.0% +0.0% +0.0%
banner +0.1% 0.0% +0.0% +0.0% +0.0%
bernouilli +0.1% 0.0% 0.0% -0.0% +0.0%
binary-trees +0.1% 0.0% -0.0% -0.0% 0.0%
boyer +0.1% 0.0% +0.0% +0.0% +0.0%
boyer2 +0.1% 0.0% +0.0% +0.0% +0.0%
bspt +0.1% 0.0% -0.0% -0.0% -0.0%
cacheprof +0.1% 0.0% -0.0% -0.0% -0.0%
calendar +0.1% 0.0% +0.0% +0.0% +0.0%
cichelli +0.1% 0.0% +0.0% +0.0% +0.0%
circsim +0.1% 0.0% +0.0% +0.0% +0.0%
clausify +0.1% 0.0% -0.0% +0.0% +0.0%
comp_lab_zift +0.1% 0.0% +0.0% +0.0% +0.0%
compress +0.1% 0.0% +0.0% +0.0% 0.0%
compress2 +0.1% 0.0% -0.0% 0.0% 0.0%
constraints +0.1% 0.0% +0.0% +0.0% +0.0%
cryptarithm1 +0.1% 0.0% +0.0% +0.0% +0.0%
cryptarithm2 +0.1% 0.0% +0.0% +0.0% +0.0%
cse +0.1% 0.0% +0.0% +0.0% +0.0%
digits-of-e1 +0.1% 0.0% +0.0% -0.0% -0.0%
digits-of-e2 +0.1% 0.0% -0.0% -0.0% -0.0%
dom-lt +0.1% 0.0% +0.0% +0.0% +0.0%
eliza +0.1% 0.0% +0.0% +0.0% +0.0%
event +0.1% 0.0% +0.0% +0.0% +0.0%
exact-reals +0.1% 0.0% +0.0% +0.0% +0.0%
exp3_8 +0.1% 0.0% +0.0% -0.0% 0.0%
expert +0.1% 0.0% +0.0% +0.0% +0.0%
fannkuch-redux +0.1% 0.0% -0.0% 0.0% 0.0%
fasta +0.1% 0.0% -0.0% +0.0% +0.0%
fem +0.1% 0.0% -0.0% +0.0% 0.0%
fft +0.1% 0.0% -0.0% +0.0% +0.0%
fft2 +0.1% 0.0% +0.0% +0.0% +0.0%
fibheaps +0.1% 0.0% +0.0% +0.0% +0.0%
fish +0.1% 0.0% +0.0% +0.0% +0.0%
fluid +0.0% 0.0% +0.0% +0.0% +0.0%
fulsom +0.1% 0.0% -0.0% +0.0% 0.0%
gamteb +0.1% 0.0% +0.0% +0.0% 0.0%
gcd +0.1% 0.0% +0.0% +0.0% +0.0%
gen_regexps +0.1% 0.0% -0.0% +0.0% 0.0%
genfft +0.1% 0.0% +0.0% +0.0% +0.0%
gg +0.1% 0.0% 0.0% +0.0% +0.0%
grep +0.1% 0.0% -0.0% +0.0% +0.0%
hidden +0.1% 0.0% +0.0% -0.0% 0.0%
hpg +0.1% 0.0% -0.0% -0.0% -0.0%
ida +0.1% 0.0% +0.0% +0.0% +0.0%
infer +0.1% 0.0% +0.0% 0.0% -0.0%
integer +0.1% 0.0% +0.0% +0.0% +0.0%
integrate +0.1% 0.0% -0.0% -0.0% -0.0%
k-nucleotide +0.1% 0.0% +0.0% +0.0% 0.0%
kahan +0.1% 0.0% +0.0% +0.0% +0.0%
knights +0.1% 0.0% -0.0% -0.0% -0.0%
lambda +0.1% 0.0% +0.0% +0.0% -0.0%
last-piece +0.1% 0.0% +0.0% 0.0% 0.0%
lcss +0.1% 0.0% +0.0% +0.0% 0.0%
life +0.1% 0.0% -0.0% +0.0% +0.0%
lift +0.1% 0.0% +0.0% +0.0% +0.0%
linear +0.1% 0.0% -0.0% +0.0% 0.0%
listcompr +0.1% 0.0% +0.0% +0.0% +0.0%
listcopy +0.1% 0.0% +0.0% +0.0% +0.0%
maillist +0.1% 0.0% +0.0% -0.0% -0.0%
mandel +0.1% 0.0% +0.0% +0.0% 0.0%
mandel2 +0.1% 0.0% +0.0% +0.0% +0.0%
mate +0.1% 0.0% +0.0% 0.0% +0.0%
minimax +0.1% 0.0% -0.0% 0.0% -0.0%
mkhprog +0.1% 0.0% +0.0% +0.0% +0.0%
multiplier +0.1% 0.0% +0.0% 0.0% 0.0%
n-body +0.1% 0.0% +0.0% +0.0% +0.0%
nucleic2 +0.1% 0.0% +0.0% +0.0% +0.0%
para +0.1% 0.0% 0.0% +0.0% +0.0%
paraffins +0.1% 0.0% +0.0% -0.0% 0.0%
parser +0.1% 0.0% -0.0% -0.0% -0.0%
parstof +0.1% 0.0% +0.0% +0.0% +0.0%
pic +0.1% 0.0% -0.0% -0.0% 0.0%
pidigits +0.1% 0.0% +0.0% -0.0% -0.0%
power +0.1% 0.0% +0.0% +0.0% +0.0%
pretty +0.1% 0.0% -0.0% -0.0% -0.1%
primes +0.1% 0.0% -0.0% -0.0% -0.0%
primetest +0.1% 0.0% -0.0% -0.0% -0.0%
prolog +0.1% 0.0% -0.0% -0.0% -0.0%
puzzle +0.1% 0.0% -0.0% -0.0% -0.0%
queens +0.1% 0.0% +0.0% +0.0% +0.0%
reptile +0.1% 0.0% -0.0% -0.0% +0.0%
reverse-complem +0.1% 0.0% +0.0% 0.0% -0.0%
rewrite +0.1% 0.0% -0.0% -0.0% -0.0%
rfib +0.1% 0.0% +0.0% +0.0% +0.0%
rsa +0.1% 0.0% -0.0% +0.0% -0.0%
scc +0.1% 0.0% -0.0% -0.0% -0.1%
sched +0.1% 0.0% +0.0% +0.0% +0.0%
scs +0.1% 0.0% +0.0% +0.0% +0.0%
simple +0.1% 0.0% -0.0% -0.0% -0.0%
solid +0.1% 0.0% +0.0% +0.0% +0.0%
sorting +0.1% 0.0% -0.0% -0.0% -0.0%
spectral-norm +0.1% 0.0% +0.0% +0.0% +0.0%
sphere +0.1% 0.0% -0.0% -0.0% -0.0%
symalg +0.1% 0.0% -0.0% -0.0% -0.0%
tak +0.1% 0.0% +0.0% +0.0% +0.0%
transform +0.1% 0.0% +0.0% +0.0% +0.0%
treejoin +0.1% 0.0% +0.0% -0.0% -0.0%
typecheck +0.1% 0.0% +0.0% +0.0% +0.0%
veritas +0.0% 0.0% +0.0% +0.0% +0.0%
wang +0.1% 0.0% 0.0% +0.0% +0.0%
wave4main +0.1% 0.0% +0.0% +0.0% +0.0%
wheel-sieve1 +0.1% 0.0% +0.0% +0.0% +0.0%
wheel-sieve2 +0.1% 0.0% +0.0% +0.0% +0.0%
x2n1 +0.1% 0.0% +0.0% +0.0% +0.0%
--------------------------------------------------------------------------------
Min +0.0% 0.0% -0.0% -0.0% -0.1%
Max +0.1% 0.0% +0.0% +0.0% +0.0%
Geometric Mean +0.1% -0.0% -0.0% -0.0% -0.0%
Bumping numbers of nonsensical perf tests:
Metric Increase:
T12150
T12234
T12425
T13035
T5837
T6048
It's simply not possible for this patch to increase allocations, and
I've wasted enough time on these test in the past (see #17686). I think
these tests should not be perf tests, but for now I'll bump the numbers.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/dce50062e35d3246b63fba9357dea6313c23c780">dce50062</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-09T16:18:44-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Rts: show errno on failure (#18033)
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/045139f40089f288866c1c59c7379be82ecdaf34">045139f4</a></strong>
<div>
<span>by Hécate</span>
<i>at 2020-04-09T23:10:44-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add an example to liftIO and explain its purpose
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/101fab6ee6cee72b9ffce40e45ebf39466d1c01a">101fab6e</a></strong>
<div>
<span>by Sebastian Graf</span>
<i>at 2020-04-09T23:11:21-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Special case `isConstraintKindCon` on `AlgTyCon`
Previously, the `tyConUnique` record selector would unfold into a huge
case expression that would be inlined in all call sites, such as the
`INLINE`-annotated `coreView`, see #18026. `constraintKindTyConKey` only
occurs as the `Unique` of an `AlgTyCon` anyway, so we can make the code
a lot more compact, but have to move it to GHC.Core.TyCon.
Metric Decrease:
T12150
T12234
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/f5212dfc10414212e42247c2f2dcc45252f7e1d2">f5212dfc</a></strong>
<div>
<span>by Sebastian Graf</span>
<i>at 2020-04-09T23:11:57-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">DmdAnal: No need to attach a StrictSig to DataCon workers
In GHC.Types.Id.Make we were giving a strictness signature to every data
constructor wrapper Id that we weren't looking at in demand analysis
anyway. We used to use its CPR info, but that has its own CPR signature
now.
`Note [Data-con worker strictness]` then felt very out of place, so I
moved it to GHC.Core.DataCon.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/75a185dc2a648ab1f592d401daa5efcacb451c83">75a185dc</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-09T23:12:37-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Hadrian: fix --summary
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/723062edf6191084a99787d3f235183cf6b7d051">723062ed</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-04-10T09:18:14+03:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">testsuite: Move no_lint to the top level, tweak hie002
- We don't want to benchmark linting so disable lints in hie002 perf
test
- Move no_lint to the top-level to be able to use it in tests other than
those in `testsuite/tests/perf/compiler`.
- Filter out -dstg-lint in no_lint.
- hie002 allocation numbers on 32-bit are unstable, so skip it on 32-bit
Metric Decrease:
hie002
ManyConstructors
T12150
T12234
T13035
T1969
T4801
T9233
T9961
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/bcafaa82a0223afd5d103e052ab9a097a676e5ea">bcafaa82</a></strong>
<div>
<span>by Peter Trommler</span>
<i>at 2020-04-10T19:29:33-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Testsuite: mark T11531 fragile
The test depends on a link editor allowing undefined symbols in an ELF
shared object. This is the standard but it seems some distributions
patch their link editor. See the report by @hsyl20 in #11531.
Fixes #11531
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/0889f5eecfea8af6a9d74d48d9d86ff3aea331d6">0889f5ee</a></strong>
<div>
<span>by Takenobu Tani</span>
<i>at 2020-04-12T11:44:52+09:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">testsuite: Fix comment for a language extension
[skip ci]
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/cd4f92b5f4251f1a37d1e08ee97d99f2ccb41f26">cd4f92b5</a></strong>
<div>
<span>by Simon Peyton Jones</span>
<i>at 2020-04-12T11:20:58-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Significant refactor of Lint
This refactoring of Lint was triggered by #17923, which is
fixed by this patch.
The main change is this. Instead of
lintType :: Type -> LintM LintedKind
we now have
lintType :: Type -> LintM LintedType
Previously, all of typeKind was effectively duplicate in lintType.
Moreover, since we have an ambient substitution, we still had to
apply the substition here and there, sometimes more than once. It
was all very tricky, in the end, and made my head hurt.
Now, lintType returns a fully linted type, with all substitutions
performed on it. This is much simpler.
The same thing is needed for Coercions. Instead of
lintCoercion :: OutCoercion
-> LintM (LintedKind, LintedKind,
LintedType, LintedType, Role)
we now have
lintCoercion :: Coercion -> LintM LintedCoercion
Much simpler! The code is shorter and less bug-prone.
There are a lot of knock on effects. But life is now better.
Metric Decrease:
T1969
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/0efaf301fec9ed9ea827392cbe03de3335e995c7">0efaf301</a></strong>
<div>
<span>by Josh Meredith</span>
<i>at 2020-04-12T11:21:34-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Implement extensible interface files
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/54ca66a7d30d7f7cfbf3753ebe547f5a20d76b96">54ca66a7</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-12T11:22:10-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Use conLikeUserTyVarBinders to quantify field selector types
This patch:
1. Writes up a specification for how the types of top-level field
selectors should be determined in a new section of the GHC User's
Guide, and
2. Makes GHC actually implement that specification by using
`conLikeUserTyVarBinders` in `mkOneRecordSelector` to preserve the
order and specificity of type variables written by the user.
Fixes #18023.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/35799dda07813e4c510237290a631d4d11fb92d2">35799dda</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-12T11:22:50-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">hadrian: Don't --export-dynamic on Darwin
When fixing #17962 I neglected to consider that --export-dynamic is only
supported on ELF platforms.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/e8029816fda7602a8163c4d2703ff02982a3e48c">e8029816</a></strong>
<div>
<span>by Alexis King</span>
<i>at 2020-04-12T11:23:27-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add an INLINE pragma to Control.Category.>>>
This fixes #18013 by adding INLINE pragmas to both Control.Category.>>>
and GHC.Desugar.>>>. The functional change in this patch is tiny (just
two lines of pragmas!), but an accompanying Note explains in gory
detail what’s going on.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/0da186c1b5a47e08e91c1c674d46c040c83932fc">0da186c1</a></strong>
<div>
<span>by Krzysztof Gogolewski</span>
<i>at 2020-04-14T07:55:20-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Change zipWith to zipWithEqual in a few places
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/074c1ccd3f8c3fcab117e336316173e8e869230a">074c1ccd</a></strong>
<div>
<span>by Andreas Klebinger</span>
<i>at 2020-04-14T07:55:55-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Small change to the windows ticker.
We already have a function to go from time to ms so use it.
Also expand on the state of timer resolution.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/b69cc8842aa7e2df52b92a9c9ad3b9d8dcf624ab">b69cc884</a></strong>
<div>
<span>by Alp Mestanogullari</span>
<i>at 2020-04-14T07:56:38-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">hadrian: get rid of unnecessary levels of nesting in source-dist
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/d0c3b0696f1ca809ebd83b5fc2c0b911cde38e77">d0c3b069</a></strong>
<div>
<span>by Julien Debon</span>
<i>at 2020-04-14T07:57:16-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">doc (Foldable): Add examples to Data.Foldable
See #17929
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/5b08e0c06e038448a63aa9bd7f163b23d824ba4b">5b08e0c0</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-14T23:28:20-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">StgCRun: Enable unwinding only on Linux
It's broken on macOS due and SmartOS due to assembler differences
(#15207) so let's be conservative in enabling it. Also, refactor things
to make the intent clearer.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/27cc2e7b1c1268e59c9d16b4530f27c0d40e9464">27cc2e7b</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-14T23:28:57-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: Don't mark evacuate_large as inline
This function has two callsites and is quite large. GCC consequently
decides not to inline and warns instead. Given the situation, I can't
blame it. Let's just remove the inline specifier.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/9853fc5e3556e733b56976b0a2fce9e82130a9ef">9853fc5e</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-14T23:29:48-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">base: Enable large file support for OFD locking impl.
Not only is this a good idea in general but this should also avoid
issue #17950 by ensuring that off_t is 64-bits.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/7b41f21bbfa9e266ba6654b08c3f9fec549c8bca">7b41f21b</a></strong>
<div>
<span>by Matthew Pickering</span>
<i>at 2020-04-14T23:30:24-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Hadrian: Make -i paths absolute
The primary reason for this change is that ghcide does not work with
relative paths. It also matches what cabal and stack do, they always
pass absolute paths.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/41230e2601703df0233860be3f7d53f3a01bdbe5">41230e26</a></strong>
<div>
<span>by Daniel Gröber</span>
<i>at 2020-04-14T23:31:01-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Zero out pinned block alignment slop when profiling
The heap profiler currently cannot traverse pinned blocks because of
alignment slop. This used to just be a minor annoyance as the whole block
is accounted into a special cost center rather than the respective object's
CCS, cf. #7275. However for the new root profiler we would like to be able
to visit _every_ closure on the heap. We need to do this so we can get rid
of the current 'flip' bit hack in the heap traversal code.
Since info pointers are always non-zero we can in principle skip all the
slop in the profiler if we can rely on it being zeroed. This assumption
caused problems in the past though, commit a586b33f8e ("rts: Correct
handling of LARGE ARR_WORDS in LDV profiler"), part of !1118, tried to use
the same trick for BF_LARGE objects but neglected to take into account that
shrink*Array# functions don't ensure that slop is zeroed when not
compiling with profiling.
Later, commit 0c114c6599 ("Handle large ARR_WORDS in heap census (fix
as we will only be assuming slop is zeroed when profiling is on.
This commit also reduces the ammount of slop we introduce in the first
place by calculating the needed alignment before doing the allocation for
small objects where we know the next available address. For large objects
we don't know how much alignment we'll have to do yet since those details
are hidden behind the allocateMightFail function so there we continue to
allocate the maximum additional words we'll need to do the alignment.
So we don't have to duplicate all this logic in the cmm code we pull it
into the RTS allocatePinned function instead.
Metric Decrease:
T7257
haddock.Cabal
haddock.base
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/15fa9bd6dd2d0b8d1fcd7135c85ea0d60853340d">15fa9bd6</a></strong>
<div>
<span>by Daniel Gröber</span>
<i>at 2020-04-14T23:31:01-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: Expand and add more notes regarding slop
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/caf3f444bcc29f75145834207da00d938c08c2d3">caf3f444</a></strong>
<div>
<span>by Daniel Gröber</span>
<i>at 2020-04-14T23:31:01-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: allocatePinned: Fix confusion about word/byte units
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/c3c0f662df06500a11970fd391d0a88e081a5296">c3c0f662</a></strong>
<div>
<span>by Daniel Gröber</span>
<i>at 2020-04-14T23:31:01-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: Underline some Notes as is conventional
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/e149dea9bb89b77d34f50075946d6b4751a974f0">e149dea9</a></strong>
<div>
<span>by Daniel Gröber</span>
<i>at 2020-04-14T23:31:38-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: Fix nomenclature in OVERWRITING_CLOSURE macros
The additional commentary introduced by commit 8916e64e5437 ("Implement
shrinkSmallMutableArray# and resizeSmallMutableArray#.") unfortunately got
this wrong. We set 'prim' to true in overwritingClosureOfs because we
_don't_ want to call LDV_recordDead().
The reason is because of this "inherently used" distinction made in the LDV
profiler so I rename the variable to be more appropriate.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/1dd3d18c2afd9e6009cd53295d26f8b31ca58fec">1dd3d18c</a></strong>
<div>
<span>by Daniel Gröber</span>
<i>at 2020-04-14T23:31:38-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove call to LDV_RECORD_CREATE for array resizing
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/19de2fb090a25ab0d640d0cd5aef09f35e7455a0">19de2fb0</a></strong>
<div>
<span>by Daniel Gröber</span>
<i>at 2020-04-14T23:31:38-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: Assert LDV_recordDead is not called for inherently used closures
The comments make it clear LDV_recordDead should not be called for
inhererently used closures, so add an assertion to codify this fact.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/0b934e30417a767063625494ecf135c9d6006f71">0b934e30</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-14T23:32:14-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Bump template-haskell version to 2.17.0.0
This requires bumping the `exceptions` and `text` submodules to bring
in commits that bump their respective upper version bounds on
`template-haskell`.
Fixes #17645. Fixes #17696.
Note that the new `text` commit includes a fair number of additions
to the Haddocks in that library. As a result, Haddock has to do more
work during the `haddock.Cabal` test case, increasing the number of
allocations it requires. Therefore,
-------------------------
Metric Increase:
haddock.Cabal
-------------------------
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/22cc8e513fcfa89a4391f075534d903596a05895">22cc8e51</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-15T17:48:47-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix #18052 by using pprPrefixOcc in more places
This fixes several small oversights in the choice of pretty-printing
function to use. Fixes #18052.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/ec77b2f16a78b13f54794c954953d8878dea9db2">ec77b2f1</a></strong>
<div>
<span>by Daniel Gröber</span>
<i>at 2020-04-15T17:49:24-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: ProfHeap: Fix wrong time in last heap profile sample
We've had this longstanding issue in the heap profiler, where the time of
the last sample in the profile is sometimes way off causing the rendered
graph to be quite useless for long runs.
It seems to me the problem is that we use mut_user_time() for the last
sample as opposed to getRTSStats(), which we use when calling heapProfile()
in GC.c.
The former is equivalent to getProcessCPUTime() but the latter does
some additional stuff:
getProcessCPUTime() - end_init_cpu - stats.gc_cpu_ns -
stats.nonmoving_gc_cpu_ns
So to fix this just use getRTSStats() in both places.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/85fc32f03a6df92ec8d4ec9accca3c11b31a1596">85fc32f0</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-17T12:45:25-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Hadrian: fix dyn_o/dyn_hi rule (#17534)
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/bfde3b76ac7f5a72eca012fe34ac1340a5ce2011">bfde3b76</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-17T12:46:02-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix #18065 by fixing an InstCo oversight in Core Lint
There was a small thinko in Core Lint's treatment of `InstCo`
coercions that ultimately led to #18065. The fix: add an apostrophe.
That's it!
Fixes #18065.
Co-authored-by: Simon Peyton Jones <simonpj@microsoft.com>
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/a05348ebaa11d563ab2e33325055317ff3cb8afc">a05348eb</a></strong>
<div>
<span>by Cale Gibbard</span>
<i>at 2020-04-17T13:08:47-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Change the fail operator argument of BindStmt to be a Maybe
Don't use noSyntaxExpr for it. There is no good way to defensively case
on that, nor is it clear one ought to do so.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/79e27144db7011f6d01a2f5ed15fd110d579bb8e">79e27144</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-04-17T13:08:47-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Use trees that grow for rebindable operators for `<-` binds
Also add more documentation.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/18bc16ed78dfa1fe9498c5ac1ca38e9f84267872">18bc16ed</a></strong>
<div>
<span>by Cale Gibbard</span>
<i>at 2020-04-17T13:08:47-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Use FailOperator in more places, define a couple datatypes (XBindStmtRn and XBindStmtTc) to help clarify the meaning of XBindStmt in the renamer and typechecker
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/84cc8394d075cea236faa0bcd9ef0a84de89ee8c">84cc8394</a></strong>
<div>
<span>by Simon Peyton Jones</span>
<i>at 2020-04-18T13:20:29-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add a missing zonk in tcHsPartialType
I omitted a vital zonk when refactoring tcHsPartialType in
commit 48fb3482f8cbc8a4b37161021e846105f980eed4
Author: Simon Peyton Jones <simonpj@microsoft.com>
Date: Wed Jun 5 08:55:17 2019 +0100
Fix typechecking of partial type signatures
This patch fixes it and adds commentary to explain why.
Fixes #18008
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/2ee96ac1aa2cbff4e70bc45988930d64599029f2">2ee96ac1</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-18T13:21:05-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">gitlab-ci: Bump FreeBSD bootstrap compiler to 8.10.1
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/434312e5fdde91d6ad7b6d199bbb560a72ab6b89">434312e5</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-18T13:21:05-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">gitlab-ci: Enable FreeBSD job for so-labelled MRs
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/ddffb2278a22b7c0e3a9fce11ada67a471243409">ddffb227</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-18T13:21:05-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">gitlab-ci: Use rules syntax for conditional jobs
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/e2586828a30202a28dcacac9ab7fc83c43da9e02">e2586828</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-18T13:21:05-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Bump hsc2hs submodule
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/15ab6cd548f284732a7f89d78c2b89b1bfc4ea1d">15ab6cd5</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-04-18T13:21:44-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Improve prepForeignCall error reporting
Show parameters and description of the error code when ffi_prep_cif
fails.
This may be helpful for debugging #17018.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/3ca52151881451ce5b3a7740d003e811b586140d">3ca52151</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-18T20:04:14+02:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">GHC.Core.Opt renaming
* GHC.Core.Op => GHC.Core.Opt
* GHC.Core.Opt.Simplify.Driver => GHC.Core.Opt.Driver
* GHC.Core.Opt.Tidy => GHC.Core.Tidy
* GHC.Core.Opt.WorkWrap.Lib => GHC.Core.Opt.WorkWrap.Utils
As discussed in:
* https://mail.haskell.org/pipermail/ghc-devs/2020-April/018758.html
* https://gitlab.haskell.org/ghc/ghc/issues/13009#note_264650
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/15312bbb53f247c9ed2c5cf75100a9f44c1c7227">15312bbb</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-18T20:04:46+02:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Modules (#13009)
* SysTools
* Parser
* GHC.Builtin
* GHC.Iface.Recomp
* Settings
Update Haddock submodule
Metric Decrease:
Naperian
parsing001
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/eaed0a3289e4c24ff1a70c6fc4b7f8bae6cd2dd3">eaed0a32</a></strong>
<div>
<span>by Alexis King</span>
<i>at 2020-04-19T03:16:44-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add missing addInScope call for letrec binders in OccurAnal
This fixes #18044, where a shadowed variable was incorrectly substituted
by the binder swap on the RHS of a floated-in letrec. This can only
happen when the uniques line up *just* right, so writing a regression
test would be very difficult, but at least the fix is small and
straightforward.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/36882493fcaa9dd2eefa7184929765189ac339ad">36882493</a></strong>
<div>
<span>by Shayne Fletcher</span>
<i>at 2020-04-20T04:36:43-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Derive Ord instance for Extension
Metric Increase:
T12150
T12234
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/b43365ad62d73afd5c58467ab9a4f9523ab09c18">b43365ad</a></strong>
<div>
<span>by Simon Peyton Jones</span>
<i>at 2020-04-20T04:37:20-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix a buglet in redundant-constraint warnings
Ticket #18036 pointed out that we were reporting a redundant
constraint when it really really wasn't.
Turned out to be a buglet in the SkolemInfo for the
relevant implication constraint. Easily fixed!
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/d5fae7da02cff1c7ec7b8e472f85d23aef098968">d5fae7da</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-04-20T14:39:28-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Mark T12010 fragile on 32-bit
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/bca02fca0119354a6201fd5d019a553015ba2dd8">bca02fca</a></strong>
<div>
<span>by Adam Sandberg Ericsson</span>
<i>at 2020-04-21T06:38:45-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">docs: drop note about not supporting shared libraries on unix systems
[skip ci]
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/6655f93324b7f1d30a6baaedfecae455d5e08e39">6655f933</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-21T06:39:32-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Use ParserFlags in GHC.Runtime.Eval (#17957)
Instead of passing `DynFlags` to functions such as `isStmt` and
`hasImport` in `GHC.Runtime.Eval` we pass `ParserFlags`. It's a much
simpler structure that can be created purely with `mkParserFlags'`.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/70be0fbcefa07ff164437476bf2809ea7c3ff495">70be0fbc</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-21T06:39:32-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">GHC.Runtime: avoid DynFlags (#17957)
* add `getPlatform :: TcM Platform` helper
* remove unused `DynFlags` parameter from `emptyPLS`
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/35e43d48a9a3ab22da90c4c2ea2c805fe762b9c5">35e43d48</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-21T06:39:32-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Avoid DynFlags in Ppr code (#17957)
* replace `DynFlags` parameters with `SDocContext` parameters for a few
Ppr related functions: `bufLeftRenderSDoc`, `printSDoc`,
`printSDocLn`, `showSDocOneLine`.
* remove the use of `pprCols :: DynFlags -> Int` in Outputable. We
already have the information via `sdocLineLength :: SDocContext ->
Int`
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/ce5c2999d2e356d034fbf1045a2383c0ac24f15f">ce5c2999</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-21T06:39:32-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Avoid using sdocWithDynFlags (#17957)
Remove one use of `sdocWithDynFlags` from `GHC.CmmToLlvm.llvmCodeGen'`
and from `GHC.Driver.CodeOutput.profilingInitCode`
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/f2a98996e7792f572ab685f29742e3476be81166">f2a98996</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-21T06:39:32-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Avoid `sdocWithDynFlags` in `pprCLbl` (#17957)
* add a `DynFlags` parameter to `pprCLbl`
* put `maybe_underscore` and `pprAsmCLbl` in a `where` clause to avoid
`DynFlags` parameters
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/747093b7c23a1cf92b564eb3d9efe2adc15330df">747093b7</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-21T06:39:32-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">CmmToAsm DynFlags refactoring (#17957)
* Remove `DynFlags` parameter from `isDynLinkName`: `isDynLinkName` used
to test the global `ExternalDynamicRefs` flag. Now we test it outside of
`isDynLinkName`
* Add new fields into `NCGConfig`: current unit id, sse/bmi versions,
externalDynamicRefs, etc.
* Replace many uses of `DynFlags` by `NCGConfig`
* Moved `BMI/SSE` datatypes into `GHC.Platform`
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/ffd7eef22f197ba44f0ced97ebc988f2d7d643a4">ffd7eef2</a></strong>
<div>
<span>by Takenobu Tani</span>
<i>at 2020-04-22T23:09:50-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">stg-spec: Modify file paths according to new module hierarchy
This patch updates file paths according to new module hierarchy [1]:
* GHC/Stg/Syntax.hs <= stgSyn/StgSyn.hs
* GHC/Types/Literal.hs <= basicTypes/Literal.hs
* GHC/Types/CostCentre.hs <= profiling/CostCentre.hs
This patch also updates old file path [2]:
* utils/genapply/Main.hs <= utils/genapply/GenApply.hs
[1]: https://gitlab.haskell.org/ghc/ghc/-/wikis/Make-GHC-codebase-more-modular
[2]: commit 0cc4aad36f
[skip ci]
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/e8a5d81b9358466f8889f679bfea9f796d85f7f3">e8a5d81b</a></strong>
<div>
<span>by Jonathan DK Gibbons</span>
<i>at 2020-04-22T23:10:28-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Refactor the `MatchResult` type in the desugarer
This way, it does a better job of proving whether or not the fail operator is used.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/dcb7fe5aa2bc331fa71b537b042ec08a7c79b1ac">dcb7fe5a</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-04-22T23:10:28-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove panic in dsHandleMonadicFailure
Rework dsHandleMonadicFailure to be correct by construction instead of
using an unreachable panic.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/cde23cd47170cc33845b6859a47dd06ee85094d8">cde23cd4</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-04-22T23:10:28-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Inline `adjustMatchResult`
It is just `fmap`
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/72cb6bcc23d2540274aac7d1b80682ef092f1615">72cb6bcc</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-04-22T23:10:28-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Generalize type of `matchCanFail`
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/401f7bb312aa6c570287d313f8b587aaebca72b2">401f7bb3</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-04-22T23:10:28-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">`MatchResult'` -> `MatchResult`
Inline `MatchResult` alias accordingly.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/6c9fae2342f19ab3e6ac688825a3817b23bf1fcc">6c9fae23</a></strong>
<div>
<span>by Alexis King</span>
<i>at 2020-04-22T23:11:12-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Mark DataCon wrappers CONLIKE
Now that DataCon wrappers don’t inline until phase 0 (see commit
b78cc64e923716ac0512c299f42d4d0012306c05), it’s important that
case-of-known-constructor and RULE matching be able to see saturated
applications of DataCon wrappers in unfoldings. Making them conlike is a
natural way to do it, since they are, in fact, precisely the sort of
thing the CONLIKE pragma exists to solve.
Fixes #18012.
This also bumps the version of the parsec submodule to incorporate a
patch that avoids a metric increase on the haddock perf tests. The
increase was not really a flaw in this patch, as parsec was implicitly
relying on inlining heuristics. The patch to parsec just adds some
INLINABLE pragmas, and we get a nice performance bump out of it (well
beyond the performance we lost from this patch).
Metric Decrease:
T12234
WWRec
haddock.Cabal
haddock.base
haddock.compiler
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/48b8951e819e5d7d06ad7e168323de320d87bbd6">48b8951e</a></strong>
<div>
<span>by Roland Senn</span>
<i>at 2020-04-22T23:11:51-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix tab-completion for :break (#17989)
In tab-completion for the `:break` command, only those
identifiers should be shown, that are accepted in the
`:break` command. Hence these identifiers must be
- defined in an interpreted module
- top-level
- currently in scope
- listed in a `ModBreaks` value as a possible breakpoint.
The identifiers my be qualified or unqualified.
To get all possible top-level breakpoints for tab-completeion
with the correct qualification do:
1. Build the list called `pifsBreaks` of all pairs of
(Identifier, module-filename) from the `ModBreaks` values.
Here all identifiers are unqualified.
2. Build the list called `pifInscope` of all pairs of
(Identifiers, module-filename) with identifiers from
the `GlobalRdrEnv`. Take only those identifiers that are
in scope and have the correct prefix.
Here the identifiers may be qualified.
3. From the `pifInscope` list seclect all pairs that can be
found in the `pifsBreaks` list, by comparing only the
unqualified part of the identifier.
The remaining identifiers can be used for tab-completion.
This ensures, that we show only identifiers, that can be used
in a `:break` command.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/34a45ee600d5346f5d1728047fa185698ed7ee84">34a45ee6</a></strong>
<div>
<span>by Peter Trommler</span>
<i>at 2020-04-22T23:12:27-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">PPC NCG: Add DWARF constants and debug labels
Fixes #11261
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/ffde234854f49dba9ec4735aad74b30fd2deee29">ffde2348</a></strong>
<div>
<span>by Simon Peyton Jones</span>
<i>at 2020-04-22T23:13:06-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Do eager instantation in terms
This patch implements eager instantiation, a small but critical change
to the type inference engine, #17173. The main change is this:
When inferring types, always return an instantiated type
(for now, deeply instantiated; in future shallowly instantiated)
There is more discussion in
https://www.tweag.io/posts/2020-04-02-lazy-eager-instantiation.html
There is quite a bit of refactoring in this patch:
* The ir_inst field of GHC.Tc.Utils.TcType.InferResultk
has entirely gone. So tcInferInst and tcInferNoInst have collapsed
into tcInfer.
* Type inference of applications, via tcInferApp and
tcInferAppHead, are substantially refactored, preparing
the way for Quick Look impredicativity.
* New pure function GHC.Tc.Gen.Expr.collectHsArgs and applyHsArgs
are beatifully dual. We can see the zipper!
* GHC.Tc.Gen.Expr.tcArgs is now much nicer; no longer needs to return
a wrapper
* In HsExpr, HsTypeApp now contains the the actual type argument,
and is used in desugaring, rather than putting it in a mysterious
wrapper.
* I struggled a bit with good error reporting in
Unify.matchActualFunTysPart. It's a little bit simpler than before,
but still not great.
Some smaller things
* Rename tcPolyExpr --> tcCheckExpr
tcMonoExpr --> tcLExpr
* tcPatSig moves from GHC.Tc.Gen.HsType to GHC.Tc.Gen.Pat
Metric Decrease:
T9961
Reduction of 1.6% in comiler allocation on T9961, I think.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/6f84aca31290afc11acde0f86969a535e519e1d5">6f84aca3</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-22T23:13:43-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: Ensure that sigaction structs are initialized
I noticed these may have uninitialized fields when looking into #18037.
The reporter says that zeroing them doesn't fix the MSAN failures they
observe but zeroing them is the right thing to do regardless.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/c29f0fa6ee831ec8a223561312d7176ef87a7ece">c29f0fa6</a></strong>
<div>
<span>by Andreas Klebinger</span>
<i>at 2020-04-22T23:14:21-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add "ddump-cmm-opt" as alias for "ddump-opt-cmm".
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/4b4a8b60a5b403e02117ab0a30a386664845586b">4b4a8b60</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-22T23:14:57-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">llvmGen: Remove -fast-llvm flag
Issue #18076 drew my attention to the undocumented `-fast-llvm` flag for
the LLVM code generator introduced in
22733532171330136d87533d523f565f2a4f102f. Speaking to Moritz about this,
the motivation for this flag was to avoid potential incompatibilities
between LLVM and the assembler/linker toolchain by making LLVM
responsible for machine-code generation.
Unfortunately, this cannot possibly work: the LLVM backend's mangler
performs a number of transforms on the assembler generated by LLVM that
are necessary for correctness. These are currently:
* mangling Haskell functions' symbol types to be `object` instead of
`function` on ELF platforms (necessary for tables-next-to-code)
* mangling AVX instructions to ensure that we don't assume alignment
(which LLVM otherwise does)
* mangling Darwin's subsections-via-symbols directives
Given that these are all necessary I don't believe that we can support
`-fast-llvm`. Let's rather remove it.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/831b66425aa3a24e769ace8d4649299ade021717">831b6642</a></strong>
<div>
<span>by Moritz Angermann</span>
<i>at 2020-04-22T23:15:33-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix build warning; add more informative information to the linker; fix linker for empty sections
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/c409961aea59d2fe2ae71036a1ae6d94c4ee05c8">c409961a</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-22T23:16:12-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Update commentary and slightly refactor GHC.Tc.Deriv.Infer
There was some out-of-date commentary in `GHC.Tc.Deriv.Infer` that
has been modernized. Along the way, I removed the `bad` constraints
in `simplifyDeriv`, which did not serve any useful purpose (besides
being printed in debugging output).
Fixes #18073.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/125aa2b8b8bb402d7819c3a35255b65c15b8bf9a">125aa2b8</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-04-22T23:16:51-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove leftover comment in tcRnModule', redundant bind
The code for the comment was moved in dc8c03b2a5c but the comment was
forgotten.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/8ea37b01b6ab16937f7b528b6bbae9fade9f1361">8ea37b01</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-22T23:17:34-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">RTS: workaround a Linux kernel bug in timerfd
Reading a timerfd may return 0: https://lkml.org/lkml/2019/8/16/335.
This is currently undocumented behavior and documentation "won't happen
anytime soon" (https://lkml.org/lkml/2020/2/13/295).
With this patch, we just ignore the result instead of crashing. It may
fix #18033 but we can't be sure because we don't have enough
information.
See also this discussion about the kernel bug:
https://github.com/Azure/sonic-swss-common/pull/302/files/1f070e7920c2e5d63316c0105bf4481e73d72dc9
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/cd8409c26d4370bf2cdcd76801974e99a9adf7b0">cd8409c2</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-23T11:39:24-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Create di_scoped_tvs for associated data family instances properly
See `Note [Associated data family instances and di_scoped_tvs]` in
`GHC.Tc.TyCl.Instance`, which explains all of the moving parts.
Fixes #18055.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/339e8ece1c844af5c9165efbc3a928890c2f75c7">339e8ece</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-23T11:40:02-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">hadrian/ghci: Allow arguments to be passed to GHCi
Previously the arguments passed to hadrian/ghci were passed both to
`hadrian` and GHCi. This is rather odd given that there are essentially
not arguments in the intersection of the two. Let's just pass them to
GHCi; this allows `hadrian/ghci -Werror`.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/5946c85abcf66555cdbcd3eed02cb8f512b6110c">5946c85a</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-23T11:40:38-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">testsuite: Don't attempt to read .std{err,out} files if they don't exist
Simon reports that he was previously seeing framework failures due to
an attempt to read the non-existing T13456.stderr. While I don't know
exactly what this is due to, it does seem like a non-existing
.std{out,err} file should be equivalent to an empty file. Teach the
testsuite driver to treat it as such.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/c42754d5fdd3c2db554d9541bab22d1b3def4be7">c42754d5</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-04-23T18:32:43-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Trees That Grow refactor for `ConPat` and `CoPat`
- `ConPat{In,Out}` -> `ConPat`
- `CoPat` -> `XPat (CoPat ..)`
Note that `GHC.HS.*` still uses `HsWrap`, but only when `p ~ GhcTc`.
After this change, moving the type family instances out of `GHC.HS.*` is
sufficient to break the cycle.
Add XCollectPat class to decide how binders are collected from XXPat based on the pass.
Previously we did this with IsPass, but that doesn't work for Haddock's
DocNameI, and the constraint doesn't express what actual distinction is being
made. Perhaps a class for collecting binders more generally is in order, but we
haven't attempted this yet.
Pure refactor of code around ConPat
- InPat/OutPat synonyms removed
- rename several identifiers
- redundant constraints removed
- move extension field in ConPat to be first
- make ConPat use record syntax more consistently
Fix T6145 (ConPatIn became ConPat)
Add comments from SPJ.
Add comment about haddock's use of CollectPass.
Updates haddock submodule.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/72da0c29cd7c336cdce3b36d1dd9e8b65a53afbd">72da0c29</a></strong>
<div>
<span>by mniip</span>
<i>at 2020-04-23T18:33:21-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add :doc to GHC.Prim
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/2c23e2e37d6c937a425c53da643aec90bda01ef6">2c23e2e3</a></strong>
<div>
<span>by mniip</span>
<i>at 2020-04-23T18:33:21-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Include docs for non-primop entries in primops.txt as well
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/0ac29c885fba7ed69de83a597cdbd03696c9ed13">0ac29c88</a></strong>
<div>
<span>by mniip</span>
<i>at 2020-04-23T18:33:21-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">GHC.Prim docs: note and test
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/b0fbfc7582fb81314dc28a056536737fb5eeaa6e">b0fbfc75</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-04-24T12:07:14-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Switch order on `GhcMake.IsBoot`
In !1798 we were requested to replace many `Bool`s with this data type.
But those bools had `False` meaning `NotBoot`, so the `Ord` instance
would be flipped if we use this data-type as-is.
Since the planned formally-`Bool` occurrences vastly outnumber the
current occurrences, we figured it would be better to conform the `Ord`
instance to how the `Bool` is used now, fixing any issues, rather than
fix them currently with the bigger refactor later in !1798. That way,
!1798 can be a "pure" refactor with no behavioral changes.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/af332442123878c1b61d236dce46418efcbe8750">af332442</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-26T13:55:14-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Modules: Utils and Data (#13009)
Update Haddock submodule
Metric Increase:
haddock.compiler
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/cd4434c8e77213bf3e6f83227fd8802c9f2a6fe2">cd4434c8</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-26T13:55:16-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix misleading Ptr phantom type in SerializedCompact (#15653)
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/22bf5c738e0339fa12940414d6448896c6733808">22bf5c73</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-04-26T13:55:22-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Tweak includes in non-moving GC headers
We don't use hash tables in non-moving GC so remove the includes.
This breaks Compact.c as existing includes no longer include Hash.h, so
include Hash.h explicitly in Compact.c.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/99823ed24b22447b14202ca57f75550773c44dbe">99823ed2</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-27T20:24:46-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">TH: fix Show/Eq/Ord instances for Bytes (#16457)
We shouldn't compare pointer values but the actual bytes.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/c62271a21b1ba1d207aaebf370c87dd884fa6ae1">c62271a2</a></strong>
<div>
<span>by Alp Mestanogullari</span>
<i>at 2020-04-27T20:25:33-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">hadrian: always capture both stdout and stderr when running a builder fails
The idea being that when a builder('s command) fails, we quite likely want to
have all the information available to figure out why. Depending on the builder
_and_ the particular problem, the useful bits of information can be printed
on stdout or stderr.
We accomplish this by defining a simple wrapper for Shake's `cmd` function,
that just _always_ captures both streams in case the command returns a non-zero
exit code, and by using this wrapper everywhere in `hadrian/src/Builder.hs`.
Fixes #18089.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/4b9764db7c190de377c06dfc71bfe6e4b37c7eb0">4b9764db</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-28T15:40:04-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Define a Quote IO instance
Fixes #18103.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/518a63d4d7e31e49a81ad66d5e5ccb1f790f6de9">518a63d4</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-04-28T15:40:42-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Make boxed 1-tuples have known keys
Unlike other tuples, which use special syntax and are "known" by way
of a special `isBuiltInOcc_maybe` code path, boxed 1-tuples do not
use special syntax. Therefore, in order to make sure that the
internals of GHC are aware of the `data Unit a = Unit a` definition
in `GHC.Tuple`, we give `Unit` known keys. For the full details, see
`Note [One-tuples] (Wrinkle: Make boxed one-tuple names have known keys)`
in `GHC.Builtin.Types`.
Fixes #18097.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/2cfc4ab9710c873a55e9a44aac9dacb06ecce36f">2cfc4ab9</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-30T01:56:56-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Document backpack fields in DynFlags
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/10a2ba90aa6a788677104cc43318c66f46e2e2b0">10a2ba90</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-30T01:56:56-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Refactor UnitInfo
* Rename InstalledPackageInfo into GenericUnitInfo
The name InstalledPackageInfo is only kept for alleged backward
compatibility reason in Cabal. ghc-boot has its own stripped down copy
of this datatype but it doesn't need to keep the name. Internally we
already use type aliases (UnitInfo in GHC, PackageCacheFormat in
ghc-pkg).
* Rename UnitInfo fields: add "unit" prefix and fix misleading names
* Add comments on every UnitInfo field
* Rename SourcePackageId into PackageId
"Package" already indicates that it's a "source package". Installed
package components are called units.
Update Haddock submodule
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/69562e34fb5d9571e9efc1cb90c879e50129a510">69562e34</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-30T01:56:56-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove unused `emptyGenericUnitInfo`
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/9e2c8e0e37a2709d5790d6c9a877a1463d6e88b5">9e2c8e0e</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-30T01:56:56-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Refactor UnitInfo load/store from databases
Converting between UnitInfo stored in package databases and UnitInfo as
they are used in ghc-pkg and ghc was done in a very convoluted way (via
BinaryStringRep and DbUnitModuleRep type classes using fun deps, etc.).
It was difficult to understand and even more to modify (I wanted to
try to use a GADT for UnitId but fun deps got in the way).
The new code uses much more straightforward functions to convert between
the different representations. Much simpler.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/ea717aa4248b2122e1f7550f30239b50ab560e4f">ea717aa4</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-30T01:56:56-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Factorize mungePackagePaths code
This patch factorizes the duplicated code used in ghc-pkg and in GHC to
munge package paths/urls.
It also fixes haddock-html munging in GHC (allowed to be either a file
or a url) to mimic ghc-pkg behavior.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/10d15f1ec4bab4dd6152d87fc66e61658a705eb3">10d15f1e</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-30T01:56:56-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Refactoring unit management code
Over the years the unit management code has been modified a lot to keep
up with changes in Cabal (e.g. support for several library components in
the same package), to integrate BackPack, etc. I found it very hard to
understand as the terminology wasn't consistent, was referring to past
concepts, etc.
The terminology is now explained as clearly as I could in the Note
"About Units" and the code is refactored to reflect it.
-------------------
Many names were misleading: UnitId is not an Id but could be a virtual
unit (an indefinite one instantiated on the fly), IndefUnitId
constructor may contain a definite instantiated unit, etc.
* Rename IndefUnitId into InstantiatedUnit
* Rename IndefModule into InstantiatedModule
* Rename UnitId type into Unit
* Rename IndefiniteUnitId constructor into VirtUnit
* Rename DefiniteUnitId constructor into RealUnit
* Rename packageConfigId into mkUnit
* Rename getPackageDetails into unsafeGetUnitInfo
* Rename InstalledUnitId into UnitId
Remove references to misleading ComponentId: a ComponentId is just an
indefinite unit-id to be instantiated.
* Rename ComponentId into IndefUnitId
* Rename ComponentDetails into UnitPprInfo
* Fix display of UnitPprInfo with empty version: this is now used for
units dynamically generated by BackPack
Generalize several types (Module, Unit, etc.) so that they can be used
with different unit identifier types: UnitKey, UnitId, Unit, etc.
* GenModule: Module, InstantiatedModule and InstalledModule are now
instances of this type
* Generalize DefUnitId, IndefUnitId, Unit, InstantiatedUnit,
PackageDatabase
Replace BackPack fake "hole" UnitId by a proper HoleUnit constructor.
Add basic support for UnitKey. They should be used more in the future to
avoid mixing them up with UnitId as we do now.
Add many comments.
Update Haddock submodule
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/8bfb0219587b969d5c8f723c46d433e9493958b4">8bfb0219</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-04-30T01:56:56-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Unit: split and rename modules
Introduce GHC.Unit.* hierarchy for everything concerning units, packages
and modules.
Update Haddock submodule
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/71484b09fa3c676e99785b3d68f69d4cfb14266e">71484b09</a></strong>
<div>
<span>by Alexis King</span>
<i>at 2020-04-30T01:57:35-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Allow block arguments in arrow control operators
Arrow control operators have their own entries in the grammar, so they
did not cooperate with BlockArguments. This was just a minor oversight,
so this patch adjusts the grammar to add the desired behavior.
fixes #18050
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/a48cd2a045695c5f34ed7b00184a8d91c4fcac0e">a48cd2a0</a></strong>
<div>
<span>by Alexis King</span>
<i>at 2020-04-30T01:57:35-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Allow LambdaCase to be used as a command in proc notation
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/f4d3773c7f4209cd3a0495ab9a29b978da48e2ff">f4d3773c</a></strong>
<div>
<span>by Alexis King</span>
<i>at 2020-04-30T01:57:35-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Document BlockArguments/LambdaCase support in arrow notation
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/5bdfdd139e5aff57631e9f1c6654dc7b8590c63f">5bdfdd13</a></strong>
<div>
<span>by Simon Peyton Jones</span>
<i>at 2020-04-30T01:58:15-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add tests for #17873
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/19b701c216246596710f0eba112ed5ee7b6bf870">19b701c2</a></strong>
<div>
<span>by Simon Peyton Jones</span>
<i>at 2020-04-30T07:30:13-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Mark rule args as non-tail-called
This was just an omission...b I'd failed to call markAllNonTailCall on
rule args. I think this bug has been here a long time, but it's quite
hard to trigger.
Fixes #18098
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/014ef4a3d9ee30b8add9118950f1f5007143bd1c">014ef4a3</a></strong>
<div>
<span>by Matthew Pickering</span>
<i>at 2020-04-30T07:30:50-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Hadrian: Improve tool-args command to support more components
There is a new command to hadrian, tool:path/to/file.hs, which returns
the options needed to compile that file in GHCi.
This is now used in the ghci script with argument `ghc/Main.hs` but its
main purpose is to support the new multi-component branch of ghcide.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/2aa676114bca40d6124ba90d13242c7c102369e0">2aa67611</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-30T21:34:44-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">nonmoving: Clear bitmap after initializing block size
Previously nonmovingInitSegment would clear the bitmap before
initializing the segment's block size. This is broken since
nonmovingClearBitmap looks at the segment's block size to determine how
much bitmap to clear.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/54dad3cf1e04f16ea00fb6a41b378e948c8ebf0f">54dad3cf</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-30T21:34:44-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">nonmoving: Explicitly memoize block count
A profile cast doubt on whether the compiler hoisted the bound out the
loop as I would have expected here. It turns out it did but nevertheless
it seems clearer to just do this manually.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/99ff8145044288a8a58c8028516903937ba3935c">99ff8145</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-04-30T21:34:44-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">nonmoving: Eagerly flush all capabilities' update remembered sets
(cherry picked from commit 2fa79119570b358a4db61446396889b8260d7957)
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/05b0a9fd136869f71245e12fdae64d42dc2ee1df">05b0a9fd</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-04-30T21:35:24-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove OneShotInfo field of LFReEntrant, document OneShotInfo
The field is only used in withNewTickyCounterFun and it's easier to
directly pass a parameter for one-shot info to withNewTickyCounterFun
instead of passing it via LFReEntrant. This also makes !2842 simpler.
Other changes:
- New Note (by SPJ) [OneShotInfo overview] added.
- Arity argument of thunkCode removed as it's always 0.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/a43620c621563deed76ba6b417e3a7a707c15d23">a43620c6</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-04-30T21:35:24-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">GHC.StgToCmm.Ticky: remove a few unused stuff
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/780de9e11014a88a4f676eb296c30fec2b07b5c2">780de9e1</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-05-01T10:37:39-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Use platform in Iface Binary
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/f8386c7b6a9d26bc5fd2c1d74d944c8df6337690">f8386c7b</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-05-01T10:37:39-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Refactor PprDebug handling
If `-dppr-debug` is set, then PprUser and PprDump styles are silently
replaced with PprDebug style. This was done in `mkUserStyle` and
`mkDumpStyle` smart constructors. As a consequence they needed a
DynFlags parameter.
Now we keep the original PprUser and PprDump styles until they are used
to create an `SDocContext`. I.e. the substitution is only performed in
`initSDocContext`.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/b3df9e780fb2f5658412c644849cd0f1e6f50331">b3df9e78</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-05-01T10:37:39-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove PprStyle param of logging actions
Use `withPprStyle` instead to apply a specific style to a SDoc.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/de9fc995c2170bc34600ee3fc80393c67cfecad1">de9fc995</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-05-01T10:37:39-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fully remove PprDebug
PprDebug was a pain to deal with consistently as it is implied by
`-dppr-debug` but it isn't really a PprStyle. We remove it completely
and query the appropriate SDoc flag instead (`sdocPprDebug`) via
helpers (`getPprDebug` and its friends).
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/8b51fcbd67ca17a6dcc2f9e5a29176f836bf11d2">8b51fcbd</a></strong>
<div>
<span>by Sebastian Graf</span>
<i>at 2020-05-01T10:38:16-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">PmCheck: Only call checkSingle if we would report warnings
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/fd7ea0fee92a60f9658254cc4fe3abdb4ff299b1">fd7ea0fe</a></strong>
<div>
<span>by Sebastian Graf</span>
<i>at 2020-05-01T10:38:16-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">PmCheck: Pick up `EvVar`s bound in `HsWrapper`s for long-distance info
`HsWrapper`s introduce evidence bindings through `WpEvLam` which the
pattern-match coverage checker should be made aware of.
Failing to do so caused #18049, where the resulting impreciseness of
imcompleteness warnings seemingly contradicted with
`-Winaccessible-code`.
The solution is simple: Collect all the evidence binders of an
`HsWrapper` and add it to the ambient `Deltas` before desugaring
the wrapped expression.
But that means we pick up many more evidence bindings, even when they
wrap around code without a single pattern match to check! That regressed
`T3064` by over 300%, so now we are adding long-distance info lazily
through judicious use of `unsafeInterleaveIO`.
Fixes #18049.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/7bfe9ac514e18c0b0e24ff55230fe98ec9db894c">7bfe9ac5</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-05-03T04:41:33-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: Enable tracing of nonmoving heap census with -ln
Previously this was not easily available to the user. Fix this.
Non-moving collection lifecycle events are now reported with -lg.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/c560dd07f506810eaabae2f582491138aa224819">c560dd07</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-05-03T04:41:33-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">users guide: Move eventlog documentation users guide
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/02543d5ef9bd7a910fc9fece895780583ab9635a">02543d5e</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-05-03T04:41:33-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">users guide: Add documentation for non-moving GC events
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/b465dd4500beffe919e8b8dcd075008399fbf446">b465dd45</a></strong>
<div>
<span>by Alexis King</span>
<i>at 2020-05-03T04:42:12-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Flatten nested casts in the simple optimizer
Normally, we aren’t supposed to generated any nested casts, since mkCast
takes care to flatten them, but the simple optimizer didn’t use mkCast,
so they could show up after inlining. This isn’t really a problem, since
the simplifier will clean them up immediately anyway, but it can clutter
the -ddump-ds output, and it’s an extremely easy fix.
closes #18112
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/8bdc03d61cb7a2f96887c86bd0b253f7c108fcde">8bdc03d6</a></strong>
<div>
<span>by Simon Peyton Jones</span>
<i>at 2020-05-04T01:56:59-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Don't return a panic in tcNestedSplice
In GHC.Tc.Gen.Splice.tcNestedSplice we were returning a
typechecked expression of "panic". That is usually OK, because
the result is discarded. But it happens that tcApp now looks at
the typechecked expression, trivially, to ask if it is tagToEnum.
So being bottom is bad.
Moreover a debug-trace might print it out.
So better to return a civilised expression, even though it is
usually discarded.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/0bf640b19d7a7ad0800152752a71c1dd4e6c696d">0bf640b1</a></strong>
<div>
<span>by Baldur Blöndal</span>
<i>at 2020-05-04T01:57:36-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Don't require parentheses around via type (`-XDerivingVia'). Fixes #18130".
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/30272412fa437ab8e7a8035db94a278e10513413">30272412</a></strong>
<div>
<span>by Artem Pelenitsyn</span>
<i>at 2020-05-04T13:19:59-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove custom ExceptionMonad class (#18075) (updating haddock submodule accordingly)
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/b9f7c08ff5aa71b7673c8136b897e6f29de01330">b9f7c08f</a></strong>
<div>
<span>by jneira</span>
<i>at 2020-05-04T13:20:37-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove unused hs-boot file
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/1d8f80cd64edd1ea6a5d4c4aa2e09ad0d077ae1b">1d8f80cd</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-05-05T03:22:46-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove references to -package-key
* remove references to `-package-key` which has been removed in 2016
(240ddd7c39536776e955e881d709bbb039b48513)
* remove support for `-this-package-key` which has been deprecated at the
same time
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/7bc3a65b467c4286377b9bded277d5a2f69160b3">7bc3a65b</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-05-05T03:23:31-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove SpecConstrAnnotation (#13681)
This has been deprecated since 2013. Use GHC.Types.SPEC instead.
Make GHC.Exts "not-home" for haddock
Metric Decrease:
haddock.base
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/3c862f635394b02c121f917a4d9ea7802033eebb">3c862f63</a></strong>
<div>
<span>by DenisFrezzato</span>
<i>at 2020-05-05T03:24:15-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix Haskell98 short description in documentation
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/2420c555e6cb681f4ef7c4ae3192a850ab431759">2420c555</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-05-05T03:24:53-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add regression tests for #16244, #16245, #16758
Commit e3c374cc5bd7eb49649b9f507f9f7740697e3f70 ended up
fixing quite a few bugs:
* This commit fixes #16244 completely. A regression test has been
added.
* This commit fixes one program from #16245. (The program in
https://gitlab.haskell.org/ghc/ghc/issues/16245#note_211369 still
panics, and the program in
https://gitlab.haskell.org/ghc/ghc/issues/16245#note_211400 still
loops infinitely.) A regression test has been added for this
program.
* This commit fixes #16758. Accordingly, this patch removes the
`expect_broken` label from the `T16758` test case, moves it from
`should_compile` to `should_fail` (as it should produce an error
message), and checks in the expected stderr.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/40c71c2cf38b4e134d81b7184a4d5e02949ae70c">40c71c2c</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-05-05T03:25:31-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix colorized error messages (#18128)
In b3df9e780fb2f5658412c644849cd0f1e6f50331 I broke colorized messages
by using "dump" style instead of "user" style. This commits fixes it.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/7ab6ab093c86227b6d33a5185ebbd11928ac9754">7ab6ab09</a></strong>
<div>
<span>by Richard Eisenberg</span>
<i>at 2020-05-06T04:39:32-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Refactor hole constraints.
Previously, holes (both expression holes / out of scope variables and
partial-type-signature wildcards) were emitted as *constraints* via
the CHoleCan constructor. While this worked fine for error reporting,
there was a fair amount of faff in keeping these constraints in line.
In particular, and unlike other constraints, we could never change
a CHoleCan to become CNonCanonical. In addition:
* the "predicate" of a CHoleCan constraint was really the type
of the hole, which is not a predicate at all
* type-level holes (partial type signature wildcards) carried
evidence, which was never used
* tcNormalise (used in the pattern-match checker) had to create
a hole constraint just to extract it again; it was quite messy
The new approach is to record holes directly in WantedConstraints.
It flows much more nicely now.
Along the way, I did some cleaning up of commentary in
GHC.Tc.Errors.Hole, which I had a hard time understanding.
This was instigated by a future patch that will refactor
the way predicates are handled. The fact that CHoleCan's
"predicate" wasn't really a predicate is incompatible with
that future patch.
No test case, because this is meant to be purely internal.
It turns out that this change improves the performance of
the pattern-match checker, likely because fewer constraints
are sloshing about in tcNormalise. I have not investigated
deeply, but an improvement is not a surprise here:
-------------------------
Metric Decrease:
PmSeriesG
-------------------------
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/420b957df9d831632a3edab682778b11734255f1">420b957d</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-05-06T04:40:08-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: Zero block flags with -DZ
Block flags are very useful for determining the state of a block.
However, some block allocator users don't touch them, leading to
misleading values. Ensure that we zero then when zero-on-gc is set. This
is safe and makes the flags more useful during debugging.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/740b3b8df76dabd88bdb3474aad2b287b0960f07">740b3b8d</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-05-06T04:40:08-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">nonmoving: Fix incorrect failed_to_evac value during deadlock gc
Previously we would incorrectly set the failed_to_evac flag if we
evacuated a value due to a deadlock GC. This would cause us to mark more
things as dirty than strictly necessary. It also turned up a nasty but
which I will fix next.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/b2d72c758233830446230800d0045badc01b42ca">b2d72c75</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-05-06T04:40:08-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">nonmoving: Fix handling of dirty objects
Previously we (incorrectly) relied on failed_to_evac to be "precise".
That is, we expected it to only be true if *all* of an object's fields
lived outside of the non-moving heap. However, does not match the
behavior of failed_to_evac, which is true if *any* of the object's
fields weren't promoted (meaning that some others *may* live in the
non-moving heap).
This is problematic as we skip the non-moving write barrier for dirty
objects (which we can only safely do if *all* fields point outside of
the non-moving heap).
Clearly this arises due to a fundamental difference in the behavior
expected of failed_to_evac in the moving and non-moving collector.
e.g., in the moving collector it is always safe to conservatively say
failed_to_evac=true whereas in the non-moving collector the safe value
is false.
This issue went unnoticed as I never wrote down the dirtiness
invariant enforced by the non-moving collector. We now define this
invariant as
An object being marked as dirty implies that all of its fields are
on the mark queue (or, equivalently, update remembered set).
To maintain this invariant we teach nonmovingScavengeOne to push the
fields of objects which we fail to evacuate to the update remembered
set. This is a simple and reasonably cheap solution and avoids the
complexity and fragility that other, more strict alternative invariants
would require.
All of this is described in a new Note, Note [Dirty flags in the
non-moving collector] in NonMoving.c.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/9f3e6884e338015f2953c4c0844e04d467f53dd5">9f3e6884</a></strong>
<div>
<span>by Zubin Duggal</span>
<i>at 2020-05-06T04:41:08-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Allow atomic update of NameCache in readHieFile
The situation arises in ghcide where multiple different threads may need to
update the name cache, therefore with the older interface it could happen
that you start reading a hie file with name cache A and produce name cache
A + B, but another thread in the meantime updated the namecache to A +
C. Therefore if you write the new namecache you will lose the A' updates
from the second thread.
Updates haddock submodule
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/edec6a6c205378caf15d1d874d7e901ba76dd293">edec6a6c</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-05-06T04:41:57-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Make isTauTy detect higher-rank contexts
Previously, `isTauTy` would only detect higher-rank `forall`s, not
higher-rank contexts, which led to some minor bugs observed
in #18127. Easily fixed by adding a case for
`(FunTy InvisArg _ _)`.
Fixes #18127.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/a95e7fe02efd2fdeec91ba46de64bc78c81381eb">a95e7fe0</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-05-06T04:42:39-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">ELF linker: increment curSymbol after filling in fields of current entry
The bug was introduced in a8b7cef4d45 which added a field to the
`symbols` array elements and then updated this code incorrectly:
- oc->symbols[curSymbol++] = nm;
+ oc->symbols[curSymbol++].name = nm;
+ oc->symbols[curSymbol].addr = symbol->addr;
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/cab1871ab93feeacf2bf9a1c65b1c919ca9c5399">cab1871a</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-05-06T04:43:21-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Move LeadingUnderscore into Platform (#17957)
Avoid direct use of DynFlags to know if symbols must be prefixed by an
underscore.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/94e7c563ab24fe452a16900a6777349970df1945">94e7c563</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-05-06T04:43:21-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Don't use DynFlags in showLinkerState (#17957)
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/9afd92512b41cf6c6de3a17b474d8d4bb01158c3">9afd9251</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-05-06T04:43:58-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Refactoring: Use bindSigTyVarsFV in rnMethodBinds
`rnMethodBinds` was explicitly using `xoptM` to determine if
`ScopedTypeVariables` is enabled before bringing type variables
bound by the class/instance header into scope. However, this `xoptM`
logic is already performed by the `bindSigTyVarsFV` function. This
patch uses `bindSigTyVarsFV` in `rnMethodBinds` to reduce the number
of places where we need to consult if `ScopedTypeVariables` is on.
This is purely refactoring, and there should be no user-visible
change in behavior.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/6f6d72b2c382860a5f7a08779b2405da8473814c">6f6d72b2</a></strong>
<div>
<span>by Brian Foley</span>
<i>at 2020-05-08T15:29:25-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove further dead code found by a simple Python script.
Avoid removing some functions that are part of an API even
though they're not used in-tree at the moment.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/78bf8bf967551f8667b766328504cfbd24df9bfb">78bf8bf9</a></strong>
<div>
<span>by Julien Debon</span>
<i>at 2020-05-08T15:29:28-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add doc examples for Bifoldable
See #17929
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/66f0a847255f15ec656a37d639556b7918f6aac2">66f0a847</a></strong>
<div>
<span>by Julien Debon</span>
<i>at 2020-05-08T15:29:29-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">doc (Bitraversable): Add examples to Bitraversable
* Add examples to Data.Bitraversable
* Fix formatting for (,) in Bitraversable and Bifoldable
* Fix mistake on bimapAccumR documentation
See #17929
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/9749fe1223d182b1f8e7e4f7378df661c509f396">9749fe12</a></strong>
<div>
<span>by Baldur Blöndal</span>
<i>at 2020-05-08T15:29:32-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Specify kind variables for inferred kinds in base.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/4e9aef9ea732e8157ee0b7fbb85b2cdfbf49de5f">4e9aef9e</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-05-08T15:29:36-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">HsSigWcTypeScoping: Pull in documentation from stray location
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/f4d5c6df56a28be5448acf43e4f45b1695ae9eb5">f4d5c6df</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-05-08T15:29:36-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Rename local `real_fvs` to `implicit_vs`
It doesn't make sense to call the "free" variables we are about to
implicitly bind the real ones.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/20570b4b5e741912d1dc3f1826ee1f78e33f3b90">20570b4b</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-05-08T15:29:36-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">A few tiny style nits with renaming
- Use case rather than guards that repeatedly scrutenize same thing.
- No need for view pattern when `L` is fine.
- Use type synnonym to convey the intent like elsewhere.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/09ac8de5777d5ca953279a6c0ee42a6fba0fcba6">09ac8de5</a></strong>
<div>
<span>by John Ericson</span>
<i>at 2020-05-08T15:29:36-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add `forAllOrNothing` function with note
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/bb35c0e573b0bc8fe6a28c00734fa124da02a755">bb35c0e5</a></strong>
<div>
<span>by Joseph C. Sible</span>
<i>at 2020-05-08T15:29:40-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Document lawlessness of Ap's Num instance</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/cdd229fff24ab19a41dd2af218108dd8c514fff7">cdd229ff</a></strong>
<div>
<span>by Joseph C. Sible</span>
<i>at 2020-05-08T15:29:40-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Apply suggestion to libraries/base/Data/Monoid.hs</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/926d2aab83dc6068cba76f71a19b040eddc6dee9">926d2aab</a></strong>
<div>
<span>by Joseph C. Sible</span>
<i>at 2020-05-08T15:29:40-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Apply more suggestions from Simon Jakobi</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/7a763cff78d2d4b23d05554e68138678cb4ba627">7a763cff</a></strong>
<div>
<span>by Adam Gundry</span>
<i>at 2020-05-08T15:29:41-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Reject all duplicate declarations involving DuplicateRecordFields (fixes #17965)
This fixes a bug that resulted in some programs being accepted that used the same
identifier as a field label and another declaration, depending on the order they
appeared in the source code.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/88e3c8150d2b2d96c3ebc0b2942c9af44071c511">88e3c815</a></strong>
<div>
<span>by Simon Peyton Jones</span>
<i>at 2020-05-08T15:29:41-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix specialisation for DFuns
When specialising a DFun we must take care to saturate the
unfolding. See Note [Specialising DFuns] in Specialise.
Fixes #18120
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/86c77b36628dcce7bc9b066fc24c8c521fecc3ee">86c77b36</a></strong>
<div>
<span>by Greg Steuck</span>
<i>at 2020-05-08T15:29:45-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Remove unused SEGMENT_PROT_RWX
It's been unused for a year and is problematic on any OS which
requires W^X for security.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/9d97f4b5ddcfdf32b52734188f595d9a11fd4879">9d97f4b5</a></strong>
<div>
<span>by nineonine</span>
<i>at 2020-05-08T15:30:03-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Add test for #16167
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/aa318338b753ab6e9db44cf2c2d285827eb35a03">aa318338</a></strong>
<div>
<span>by Ryan Scott</span>
<i>at 2020-05-08T15:30:04-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Bump exceptions submodule so that dist-boot is .gitignore'd
`exceptions` is a stage-0 boot library as of commit
30272412fa437ab8e7a8035db94a278e10513413, which means that building
`exceptions` in a GHC tree will generate a `dist-boot` directory.
However, this directory was not specified in `exceptions`'
`.gitignore` file, which causes it to dirty up the current `git`
working directory.
Accordingly, this bumps the `exceptions` submodule to commit
ghc/packages/exceptions@23c0b8a50d7592af37ca09beeec16b93080df98f,
which adds `dist-boot` to the `.gitignore` file.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/ea86360f21e8c9812acba8dc1bc2a54fef700ece">ea86360f</a></strong>
<div>
<span>by Ömer Sinan Ağacan</span>
<i>at 2020-05-08T15:30:30-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Linker.c: initialize n_symbols of ObjectCode with other fields
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/951c1fb03d80094c8b0d9bcc463d86fa71695b3a">951c1fb0</a></strong>
<div>
<span>by Sylvain Henry</span>
<i>at 2020-05-09T21:46:38-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Fix unboxed-sums GC ptr-slot rubbish value (#17791)
This patch allows boot libraries to use unboxed sums without implicitly
depending on `base` package because of `absentSumFieldError`.
See updated Note [aBSENT_SUM_FIELD_ERROR_ID] in GHC.Core.Make
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/b352d63cbbfbee69358c198edd876fe7ef9d63ef">b352d63c</a></strong>
<div>
<span>by Ben Gamari</span>
<i>at 2020-05-09T21:47:14-04:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">rts: Make non-existent linker search path merely a warning
As noted in #18105, previously this resulted in a rather intrusive error
message. This is in contrast to the general expectation that search
paths are merely places to look, not places that must exist.
Fixes #18105.
</pre>
</li>
<li>
<strong><a href="https://gitlab.haskell.org/ghc/ghc/-/commit/5e3fee26e3791807ff7b99a4feecfe2da41ee316">5e3fee26</a></strong>
<div>
<span>by Andreas Klebinger</span>
<i>at 2020-05-11T15:01:34+02:00</i>
</div>
<pre class="commit-message" style="white-space: pre-wrap; margin: 0;">Refactor linear reg alloc to remember past assignments.
When assigning registers we now first try registers we
assigned to in the past, instead of picking the "first"
one.
This is in extremely helpful when dealing with loops for
which variables are dead for part of the loop.
This is important for patterns like this:
foo = arg1
loop:
use(foo)
...
foo = getVal()
goto loop;
There we:
* assign foo to the register of arg1.
* use foo, it's dead after this use as it's overwritten after.
* do other things.
* look for a register to put foo in.
If we pick an arbitrary one it might differ from the register the
start of the loop expect's foo to be in.
To fix this we simply look for past register assignments for
the given variable. If we find one and the register is free we
use that register.
This reduces the need for fixup blocks which match the register
assignment between blocks. In the example above between the end
and the head of the loop.
This patch also moves branch weight estimation ahead of register
allocation and adds a flag to control it (cmm-static-pred).
* It means the linear allocator is more likely to assign the hotter
code paths first.
* If it assign these first we are:
+ Less likely to spill on the hot path.
+ Less likely to introduce fixup blocks on the hot path.
These two measure combined are surprisingly effective. Based on nofib
we get in the mean:
* -0.9% instructions executed
* -0.1% reads/writes
* -0.2% code size.
* -0.1% compiler allocations.
* -0.9% compile time.
* -0.8% runtime.
Most of the benefits are simply a result of removing redundant moves
and spills.
Reduced compiler allocations likely are the result of less code being
generated. (The added lookup is mostly non-allocating).
</pre>
</li>
</ul>
<h4>30 changed files:</h4>
<ul>
<li class="file-stats">
<a href="#587d266bb27a4dc3022bbed44dfa19849df3044c">
.gitlab-ci.yml
</a>
</li>
<li class="file-stats">
<a href="#157f7634c25bc6366cb7c9c9edb48e819dce38db">
.gitlab/ci.sh
</a>
</li>
<li class="file-stats">
<a href="#abe895765c4ce08c5dfbc95e5e3c5db67ff92ded">
CODEOWNERS
</a>
</li>
<li class="file-stats">
<a href="#d0d96a6d03668aeab20ebe05e2c4ccb798c7e64c">
compiler/GHC.hs
</a>
</li>
<li class="file-stats">
<a href="#0887cf39c5cdf9cf8d6758f410d7dab3023c0d77">
compiler/prelude/PrelNames.hs
→
compiler/GHC/Builtin/Names.hs
</a>
</li>
<li class="file-stats">
<a href="#57f535740df5928fb0193abc3b28ca771369d8fd">
compiler/prelude/PrelNames.hs-boot
→
compiler/GHC/Builtin/Names.hs-boot
</a>
</li>
<li class="file-stats">
<a href="#06764eb0158306b83ab1998d18316392a51838c2">
compiler/prelude/THNames.hs
→
compiler/GHC/Builtin/Names/TH.hs
</a>
</li>
<li class="file-stats">
<a href="#a1519b7fe8a0d4b42e4aaa927fb6ab5b5da0fcdd">
compiler/prelude/PrimOp.hs
→
compiler/GHC/Builtin/PrimOps.hs
</a>
</li>
<li class="file-stats">
<a href="#dc9d549002b8cd260ee6d1d2fb35877c74412f91">
<span class="new-file">
+
compiler/GHC/Builtin/PrimOps.hs-boot
</span>
</a>
</li>
<li class="file-stats">
<a href="#377cfd14c1f92357465df995ec6537b074051322">
compiler/prelude/TysWiredIn.hs
→
compiler/GHC/Builtin/Types.hs
</a>
</li>
<li class="file-stats">
<a href="#be7a5c9dc04ecfe7bedb2a2afcc2a51be6719577">
compiler/prelude/TysWiredIn.hs-boot
→
compiler/GHC/Builtin/Types.hs-boot
</a>
</li>
<li class="file-stats">
<a href="#02362b473a022fb921814e97a6beba08107d38b1">
compiler/typecheck/TcTypeNats.hs
→
compiler/GHC/Builtin/Types/Literals.hs
</a>
</li>
<li class="file-stats">
<a href="#8a5cd068459120cddf3814e7b9e02003b87647ba">
compiler/prelude/TysPrim.hs
→
compiler/GHC/Builtin/Types/Prim.hs
</a>
</li>
<li class="file-stats">
<a href="#8dc7109003a77f8a82e987dc1de31466aa956174">
compiler/prelude/KnownUniques.hs
→
compiler/GHC/Builtin/Uniques.hs
</a>
</li>
<li class="file-stats">
<a href="#6bcb866fdb5388db4ecc395e443a3af4888d9dd5">
compiler/prelude/KnownUniques.hs-boot
→
compiler/GHC/Builtin/Uniques.hs-boot
</a>
</li>
<li class="file-stats">
<a href="#d95fdf6575459444666f72b2281534e0558a4ba0">
compiler/prelude/PrelInfo.hs
→
compiler/GHC/Builtin/Utils.hs
</a>
</li>
<li class="file-stats">
<a href="#451725cc4e5d443a3b7c2adcdf224840f953b7e2">
compiler/prelude/primops.txt.pp
→
compiler/GHC/Builtin/primops.txt.pp
</a>
</li>
<li class="file-stats">
<a href="#2f6f8d6d05acc04b08fff94df4b3996c65b87892">
compiler/GHC/ByteCode/Asm.hs
</a>
</li>
<li class="file-stats">
<a href="#16db773e94d0938489b415eb3231cadb2565b84d">
compiler/GHC/ByteCode/InfoTable.hs
</a>
</li>
<li class="file-stats">
<a href="#073b107caa98ea426694eacd6c08b492801a51a0">
compiler/GHC/ByteCode/Instr.hs
</a>
</li>
<li class="file-stats">
<a href="#11e6f6a348be9920cecad0893a25350137524b4f">
compiler/GHC/ByteCode/Linker.hs
</a>
</li>
<li class="file-stats">
<a href="#5c66928780aaad0eb5888511dc4b0b08492c69fa">
compiler/GHC/ByteCode/Types.hs
</a>
</li>
<li class="file-stats">
<a href="#f73a4fa90a8eb153bccdcfcc9f63c15edcd66785">
compiler/GHC/Cmm.hs
</a>
</li>
<li class="file-stats">
<a href="#2635960270885615c76f7437d2eb6c5bd6082895">
compiler/GHC/Cmm/BlockId.hs
</a>
</li>
<li class="file-stats">
<a href="#db697f6aea9f93f1583f1d5c62d25570a1e07f73">
compiler/GHC/Cmm/CLabel.hs
</a>
</li>
<li class="file-stats">
<a href="#d088ba20f051734394bf7ca283f33ed8127bc8ab">
compiler/GHC/Cmm/CallConv.hs
</a>
</li>
<li class="file-stats">
<a href="#806448db91cc2906ebcc088107220a663d3d43eb">
compiler/GHC/Cmm/CommonBlockElim.hs
</a>
</li>
<li class="file-stats">
<a href="#359dccbd5e329f4f4f3c88b6d43f0ad5dd435fe3">
compiler/GHC/Cmm/ContFlowOpt.hs
</a>
</li>
<li class="file-stats">
<a href="#ae3febe6c6eb7c487d9f1021b113402ae6148bae">
compiler/GHC/Cmm/Dataflow.hs
</a>
</li>
<li class="file-stats">
<a href="#eae45922f6e633780395508f44c14a5ed7959e7a">
compiler/GHC/Cmm/Dataflow/Block.hs
</a>
</li>
</ul>
<h5>The diff was not included because it is too large.</h5>
</div>
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