GitLab

See the new note.

Test Plan:
manual testing with patched gdb

Reviewers: bgamari, simonmar, erikd

Subscribers: rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4666

This reverts commit 5fe6aaa3.

We introduce a new Id for unused pointer values in unboxed sums that is
not CAFFY. Because the Id is not CAFFY it doesn't make non-CAFFY
definitions CAFFY, fixing #15038.

To make sure anything referenced by the new id will be retained we get a
stable pointer to in on RTS startup.

Test Plan: Passes validate

Reviewers: simonmar, simonpj, hvr, bgamari, erikd

Reviewed By: simonmar

Subscribers: rwbarton, thomie, carter

GHC Trac Issues: #15038

Differential Revision: https://phabricator.haskell.org/D4680

Summary:
Space leaks in GHCi emerge from time to time and tend to come back again
after they get fixed. This is an attempt to limit regressions by

* adding a reliable detection for some classes of space leaks in GHCi
* turning on leak checking for all GHCi tests in the test suite, so that
  we'll notice if the leak appears again.

The idea for detecting space leaks is quite simple:

* find some data that we expect to be GC'd later, make a weak pointer to it
* when we expect the data to be dead, do a `performGC` and then check
  the status of the weak pointer.

It would be nice to apply this trick to lots of things in GHC,
e.g. ensuring that HsSyn is not retained after the desugarer, or
ensuring that CoreSyn from the previous simplifier pass is not retained.

Test Plan: validate

Reviewers: bgamari, simonpj, erikd, niteria

Subscribers: thomie, carter

GHC Trac Issues: #15111

Differential Revision: https://phabricator.haskell.org/D4658

Summary:
The element type of `List` maybe a type family instacen, rather than a trivial type.
For example in Trac #14547,

```
{-# LANGUAGE TypeFamilies, OverloadedLists #-}

class Foo f where
        type It f
        foo :: [It f] -> f

data List a = Empty | a :! List a deriving Show

instance Foo (List a) where
        type It (List a) = a
        foo [] = Empty
        foo (x : xs) = x :! foo xs
```

Here the element type of `[]` is `It (List a)`, we should also normalize
it as `a`.

Test Plan: make test TEST="T14547"

Reviewers: bgamari

Reviewed By: bgamari

Subscribers: thomie, carter

GHC Trac Issues: #14547

Differential Revision: https://phabricator.haskell.org/D4624

This reverts commit 981bf471.

The element type of `List` maybe a type family instacen, rather than a
trivial type.
For example in Trac #14547,

```
{-# LANGUAGE TypeFamilies, OverloadedLists #-}

class Foo f where
        type It f
        foo :: [It f] -> f

data List a = Empty | a :! List a deriving Show

instance Foo (List a) where
        type It (List a) = a
        foo [] = Empty
        foo (x : xs) = x :! foo xs
```

Here the element type of `[]` is `It (List a)`, we should also normalize
it as `a`.

Test Plan: make test TEST="T14547"

Reviewers: bgamari

Reviewed By: bgamari

Subscribers: thomie, carter

GHC Trac Issues: #14547

Differential Revision: https://phabricator.haskell.org/D4624

This reverts commit 361d23a8.

This discussion will be useful for users; move it into the users-guide proper.
Also fixes a few typos noted by @Phyx.

Test Plan: Read it

Reviewers: Phyx

Reviewed By: Phyx

Subscribers: dfeuer, Phyx, rwbarton, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4420

This patch deletes quite a bit of code,
AND fixes Trac #15116.

This refactoring was provoked by our conversation on
Trac #14152.  No change in behaviour.

This was failing on Darwin; I believe this is due to 33de71fa.

This function was unstable, in particular for negative arguments.

https://ghc.haskell.org/trac/ghc/ticket/14927

The reason is that the formula `log (x + sqrt (1 + x*x))` is dominated
by the numerical error of the `sqrt` function when x is strongly negative
(and thus the summands in the `log` mostly cancel). However, the area
hyperbolic sine is an odd function, thus the negative side can as well
be calculated by flipping over the positive side, which avoids this instability.

Furthermore, for _very_ big arguments, the `x*x` subexpression overflows. However,
long before that happens, the square root is anyways completely dominated
by that term, so we can neglect the `1 +` and get

    sqrt (1 + x*x) ≈ sqrt (x*x) = x

and therefore

    asinh x ≈ log (x + x) = log (2*x) = log 2 + log x

which does not overflow for any normal-finite positive argument, but
perfectly matches the exact formula within the floating-point accuracy.

The area hyperbolic sine is currently broken,
see https://ghc.haskell.org/trac/ghc/ticket/14927.

These functions have inverses only on part of the real line, but
there they should be reliably inverted – that's basically the whole
point of the functions like `asin`, `atan` etc..

This is mostly for congruence with 'subWordC#' and '{add,sub}IntC#'.
I found 'plusWord2#' while implementing this, which both lacks
documentation and has a slightly different specification than
'addWordC#', which means the generic implementation is unnecessarily
complex.

While I was at it, I also added lacking meta-information on PrimOps
and refactored 'subWordC#'s generic implementation to be branchless.

Reviewers: bgamari, simonmar, jrtc27, dfeuer

Reviewed By: bgamari, dfeuer

Subscribers: dfeuer, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4592

Reviewers: bgamari

Subscribers: thomie, carter

GHC Trac Issues: #14982

Differential Revision: https://phabricator.haskell.org/D4548

Subscribers: thomie, carter, RyanGlScott

GHC Trac Issues: #15067

Differential Revision: https://phabricator.haskell.org/D4622

The element type of `List` maybe a type family instacen, rather than a
trivial type.  For example in Trac #14547,

```
{-# LANGUAGE TypeFamilies, OverloadedLists #-}

class Foo f where
        type It f
        foo :: [It f] -> f

data List a = Empty | a :! List a deriving Show

instance Foo (List a) where
        type It (List a) = a
        foo [] = Empty
        foo (x : xs) = x :! foo xs
```

Here the element type of `[]` is `It (List a)`, we should also normalize
it as `a`.

Test Plan: make test TEST="T14547"

Reviewers: bgamari

Reviewed By: bgamari

Subscribers: thomie, carter

GHC Trac Issues: #14547

Differential Revision: https://phabricator.haskell.org/D4624

Splitting TrieMap into a general and core specific part allows us to
define instances for TrieMap without creating a transitive dependency on
CoreSyn.

Test Plan: ci

Reviewers: goldfire, bgamari, simonmar, simonpj

Reviewed By: bgamari, simonpj

Subscribers: simonpj, nomeata, thomie, carter

GHC Trac Issues: #15082

Differential Revision: https://phabricator.haskell.org/D4618

See #15086.

[skip-ci]

`:'` in explanation text should be `':` to match code example.

The ‘haskell’ images are not being updated and there is no image with GHC
8.4.2, so we probably should not use them anymore. I adapted Dockerfiles
used by those images so the end result is almost the same except we get
newer GHC and cabal-install.

This patch made the simplifier inline nested function bindings less aggressively
and, while it didn't seem to affect nofib, appears to have regressed T9630
rather considerably.

This patch has virtually no effect on anything (according to a
nofib run).  But it simplifies the definition of interesting_call
by being a bit less gung-ho about inlining nested function
bindings.  See Note [Nested functions]

-----------------------------------------------------------------------
        Program           Size    Allocs   Runtime   Elapsed  TotalMem
-----------------------------------------------------------------------
           anna          +0.2%     -0.0%     0.163     0.163      0.0%
   binary-trees          +0.1%     +0.0%     -4.5%     -4.5%      0.0%
      cacheprof          -0.1%     +0.1%     -4.7%     -4.8%     +2.7%
          fasta          +0.2%      0.0%     +2.6%     +3.0%      0.0%
          fluid          -0.0%     -0.6%     0.011     0.011      0.0%
         gamteb          -0.1%     -0.0%     0.069     0.070      0.0%
            hpg          +0.1%     +0.0%     +0.7%     +0.7%      0.0%
          infer          +0.3%     +0.2%     0.097     0.098      0.0%
         lambda          -0.1%     -0.0%     +2.0%     +2.0%      0.0%
         n-body          +0.1%     -0.1%     -0.1%     -0.1%      0.0%
         simple          -0.2%     -0.2%     +0.6%     +0.6%      0.0%
  spectral-norm          +0.1%     -0.0%     -0.1%     -0.1%      0.0%
            tak          -0.0%     -0.1%     0.024     0.024      0.0%
--------------------------------------------------------------------------------
            Min          -0.4%     -0.6%     -5.3%     -5.3%      0.0%
            Max          +0.3%     +0.2%     +3.3%     +3.3%    +15.0%
 Geometric Mean          -0.0%     -0.0%     -0.3%     -0.3%     +0.2%

@osa1 reported that the output on his machine has extra newlines:
https://phabricator.haskell.org/D4606#129092. This collapses consecutive
newlines.

Test Plan: via CI

Reviewers: bgamari

Subscribers: dfeuer, thomie, carter

Differential Revision: https://phabricator.haskell.org/D4640

Test Plan: Validate, run program with `+RTS --numa` without libnuma
support compiled in

Reviewers: erikd, simonmar

Subscribers: thomie, carter

GHC Trac Issues: #14956

Differential Revision: https://phabricator.haskell.org/D4556

Test Plan: make test TEST=T15055

Reviewers: bgamari, RyanGlScott, osa1, Iceland_jack

Reviewed By: osa1

Subscribers: ulysses4ever, thomie, carter

GHC Trac Issues: #15055

Differential Revision: https://phabricator.haskell.org/D4621

GHC and the build tools use "response files" to work around the limit
on the length of command line arguments on Windows. Haddock's
implementation of parsing response files (i.e escaping/unescaping the
appropriate characters) seems complete, is well tested, and also
closely matches the GCC version. This patch moves the relevant bits
into `base` so that it's easier for other libraries to reuse it.

Test Plan: make test TEST=T13896

Reviewers: bgamari, RyanGlScott, 23Skidoo, hvr

Reviewed By: RyanGlScott

Subscribers: thomie, carter

GHC Trac Issues: #13896

Differential Revision: https://phabricator.haskell.org/D4612

In `manifestSp` the unwind info was before the relevant instruction, not
after.  I added some notes to establish semantics.  Also removes
redundant annotation in stg_catch_frame.

For `makeFixupBlocks` it looks like we were off by `wORD_SIZE dflags`.
I'm not sure why, but it lines up with `manifestSp`.  In fact it lines
up so well so that I can consolidate the Sp unwind logic in
`maybeAddUnwind`.  I detected the problems with `makeFixupBlocks` by
running T14779b after patching D4559.

Test Plan: added a new test

Reviewers: bgamari, scpmw, simonmar, erikd

Reviewed By: bgamari

Subscribers: thomie, carter

GHC Trac Issues: #14999

Differential Revision: https://phabricator.haskell.org/D4606

* osNumaNodes now returns the right number of nodes
* thread affinity is now correctly set

TODO: no noticeable performance improvement.
does windows already distribute threads in a NUMA-aware fashion?

Test Plan:
* validate
* local tests on a NUMA machine

Reviewers: bgamari, erikd, simonmar

Reviewed By: bgamari, simonmar

Subscribers: thomie, carter

Differential Revision: https://phabricator.haskell.org/D4607

Reviewers: mrkkrp, bgamari

Reviewed By: mrkkrp, bgamari

Subscribers: thomie, carter

GHC Trac Issues: #15093

Differential Revision: https://phabricator.haskell.org/D4646

Reviewers: bgamari

Reviewed By: bgamari

Subscribers: thomie, carter

GHC Trac Issues: #15093

Differential Revision: https://phabricator.haskell.org/D4645