A long debate is in issue #8742, but the main motivation is that this
allows for applying a patch to reuse the function scavenge_small_bitmap
without changing the .o-file output.

Similarly, I changed the types in rts/sm/Compact.c, so I can create
a STATIC_INLINE function for the redundant code block:

        while (size > 0) {
            if ((bitmap & 1) == 0) {
                thread((StgClosure **)p);
            }
            p++;
            bitmap = bitmap >> 1;
            size--;
        }

Issue discovered by Coverity Scan, CID 43168.
Signed-off-by: Austin Seipp <austin@well-typed.com>

Issue discovered by Coverity Scan, CID 43171.
Signed-off-by: Austin Seipp <austin@well-typed.com>

Signed-off-by: Austin Seipp <austin@well-typed.com>

This commit also makes better names for several of these functions,
and removes one that went unused.

This reverts commit 4539400a.

Signed-off-by: Austin Seipp <austin@well-typed.com>

The new stg_gc_prim_p_ll stack frame was missing an info table.  This
is a regression since 7.6, because this stuff was part of a cleanup
that happened in 7.7.

This is the result of an email conversation (off list) with
Conal Elliott, who needed a stronger unSubCo_maybe. This
commit adds cases to upgrade the role of a coercion when
recursion is necessary to do say (for example, for a use of
TransCo). As a side effect, more coercion optimizations are
now possible.

This was not done previously because unSubCo_maybe was used
only during coercion optimization, and the recursive cases
looked to be unlikely. However, adding them can cause no harm.

unSubCo_maybe is now also exported from Coercion, for use
cases like Conal's.

We now display the foralls of a type if any of the type variables
is polykinded.  This put kind polymorphism "in your face" a bit more
often, but eliminates a lot of head scratching.

The user manual reflects the new behaviour.

The provided tests test both annotation generation and reification
from Template Haskell.  Both --make and compilation via separate
units (ghc -c) are tested.
Signed-off-by: Austin Seipp <austin@well-typed.com>

The reifyAnnotation method of the Q monad correctly gathered annotations
from TCG and EPS.  Unfortunately it didn't look into the Home Package
Table.  This resulted in annotations not being found if they are in the
same package as the splice that is reifying and ghc --make is used for
compilation management.  Fix this by using the already existing
prepareAnnotations method from HscTypes.lhs that correctly searches
in HPT and EPS both.
Signed-off-by: Austin Seipp <austin@well-typed.com>

Signed-off-by: Austin Seipp <austin@well-typed.com>

Many of these have never been initialised, I think.  They
were simply guesses from the 64-bit version.

The argument in Trac #9033 is very compelling: we should not report 20
errors, fix one, and have the other 19 disappear.  They were spurious
in the first place.

The fix was easy; do type-class defaulting uncondionally, rather than
only if there are no insoluble constraints.

See Note [When to do type-class defaulting] in TcSimplify.

Error messages generally improve, especially tc211 which actually
had an example of precisely this phenomenon.

The Commentary is now on the wiki and far more complete. This copy will
of course live on in the annals of history, but there's no reason to
keep it around still.
Signed-off-by: Austin Seipp <austin@well-typed.com>

`make clean` did already ignore a missing mk/config.mk,
but `make distclean` and `make maintainer-clean` didn't.
This commit rectifies this oversight.
Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>

Issue discovered by Coverity scan, CID 43167.
Signed-off-by: Austin Seipp <austin@well-typed.com>

Issue discovered by Coverity scan, CID 43163. This should fix CID 43172 as a
side-effect as well.
Signed-off-by: Austin Seipp <austin@well-typed.com>

Issue discovered by Coverity scan, CID 43165.
Signed-off-by: Austin Seipp <austin@well-typed.com>

Issue discovered by Coverity scan, CID 43142.
Signed-off-by: Austin Seipp <austin@well-typed.com>

CID 43178
Signed-off-by: Austin Seipp <austin@well-typed.com>

n_capabilities is declared as unsigned int (32bit), and so multiplication
is 32-bit before being stored in a 64bit integer (StgWord).

Instead, cast n_capabilities to StgWord before multiplying.

Discovered by Coverity. CID 43164.
Signed-off-by: Austin Seipp <austin@well-typed.com>

Discovered by Coverity. CID 43166.
Signed-off-by: Austin Seipp <austin@well-typed.com>

This is an attempt to address

  https://github.com/haskell/cabal/issues/1811

by replicating the less than 100 lines of code actually used from the
containers package into an internal non-exposed `template-haskell` module.

Moreover, `template-haskell` does not expose the `Map` type, so this change
should have no visible effect on the public API.

It may turn out that `Data.Map` is not necessary and that even a simple
list-based associative list (`Prelude.lookup`) may suffice. However, in
order to avoid any regressions, this commit takes the safe route and just
clones `Data.Map` for now.
Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>

See Note [Do not eta-expand PAPs] in SimplUtils.  This has a tremendously
good effect on compile times for some simple benchmarks.

The test is now where it belongs, in perf/compiler/T9020 (instead of simpl015).

I did a nofib run and got essentially zero change except for cacheprof which
gets 4% more allocation.  I investigated.  Turns out that we have

    instance PP Reg where
       pp ppm ST_0 = "%st"
       pp ppm ST_1 = "%st(1)"
       pp ppm ST_2 = "%st(2)"
       pp ppm ST_3 = "%st(3)"
       pp ppm ST_4 = "%st(4)"
       pp ppm ST_5 = "%st(5)"
       pp ppm ST_6 = "%st(6)"
       pp ppm ST_7 = "%st(7)"
       pp ppm r    = "%" ++ map toLower (show r)

That (map toLower (show r) does a lot of map/toLowers.  But if we inline show
we get something like

       pp ppm ST_0 = "%st"
       pp ppm ST_1 = "%st(1)"
       pp ppm ST_2 = "%st(2)"
       pp ppm ST_3 = "%st(3)"
       pp ppm ST_4 = "%st(4)"
       pp ppm ST_5 = "%st(5)"
       pp ppm ST_6 = "%st(6)"
       pp ppm ST_7 = "%st(7)"
       pp ppm EAX  = map toLower (show EAX)
       pp ppm EBX  = map toLower (show EBX)
       ...etc...

and all those map/toLower calls can now be floated to top level.
This gives a 4% decrease in allocation.  But it depends on inlining
a pretty big 'show' function.

With this new patch we get slightly better eta-expansion, which makes
a function look slightly bigger, which just stops it being inlined.
The previous behaviour was luck, so I'm not going to worry about
losing it.

I've added some notes to nofib/Simon-nofib-notes

Previously we always printed qualified names, but that makes a lot of debug or
warning output very verbose. So now we only print qualified names with -dppr-debug.

Civilised output (from pukka error messages, with the environment available) is
unaffected

This is just to make sure that there is no redundant boxing.
For safeIndex, for example, the error path doesn't evaluate the
index, so it may be passed boxed unless safeIndex is inlined bodily,
which I don't want to rely on.

The code before did actually unpack the size, I think, but it
wasn't very clear, and it's better to do it explicitly

This quiets down the utils/testremove/checkremove step

Basically the idea is to have 'make clean' remove everything that was
generated by `make`, while `make distclean` ought to remove everything
created by `./configure`.
Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>

This adapts the foreachLibrary rule to match the new situation of
base.git, ghc-prim.git, integer-gmp.git, integer-simple.git, and
template-haskell.git being folded into ghc.git (re #9016), and thus
not being mentioned anymore in the `packages` file.

One visible effect of this oversight was that the `clean_libraries`
make target would fail to clean those packages.
Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>

Note: the .gitignore pattern rules are not that obvious
Signed-off-by: Herbert Valerio Riedel <hvr@gnu.org>