Summary:
* getNonClobberedReg instead of getSomeReg, because the reg needs to
  survive across t_code
* Use a new reg for the table offset calculation instead of clobbering
  the reg returned by expr (this was the bug affecting #12433)

Test Plan: New unit test; validate

Reviewers: rwbarton, bgamari, austin, erikd

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2529

GHC Trac Issues: #12433

Sigh.  I added some comments to the source files,
and failed to revalidate.  But the comments change the
line number in the error messages.  Doh.

I must have failed to validate properly, sorry.
These testsuite wibbles belong with

  commit 03541cba
  Author: Simon Peyton Jones <simonpj@microsoft.com>
  Date:   Fri Sep 9 17:42:42 2016 +0100

      Be less picky about reporing inaccessible code

Ben Gamari authored 8 years ago and Ben Gamari committed 8 years ago

Biographical profiling is not thread-safe as documented in #12019. Throw
an error when it is used in this way.

Test Plan: Validate

Reviewers: simonmar, austin, erikd

Reviewed By: erikd

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2516

GHC Trac Issues: #12019

As requested in #10267. However we still lack support in typed splices.
See #10945 and #10946.

Remove a leftover note in the users guide claiming that TH doesn't
support pattern synonyms.

Not sure how this snuck through but it seems to be the only one.

Triggered by the discussion on Trac #12466, this patch
makes GHC less aggressive about reporting an error when
there are insoluble Givens.

Being so agressive was making some libraries fail to
compile, and is arguably wrong in at least some cases.
See the discussion on the ticket.

Several test now pass when they failed before; see
the files-modified list for this patch.

Summary:
This is a fast, non-blocking, asynchronous, interface to tryPutMVar that
can be called from C/C++.

It's useful for callback-based C/C++ APIs: the idea is that the callback
invokes hs_try_putmvar(), and the Haskell code waits for the callback to
run by blocking in takeMVar.

The callback doesn't block - this is often a requirement of
callback-based APIs.  The callback wakes up the Haskell thread with
minimal overhead and no unnecessary context-switches.

There are a couple of benchmarks in
testsuite/tests/concurrent/should_run.  Some example results comparing
hs_try_putmvar() with using a standard foreign export:

    ./hs_try_putmvar003 1 64 16 100 +RTS -s -N4     0.49s
    ./hs_try_putmvar003 2 64 16 100 +RTS -s -N4     2.30s

hs_try_putmvar() is 4x faster for this workload (see the source for
hs_try_putmvar003.hs for details of the workload).

An alternative solution is to use the IO Manager for this.  We've tried
it, but there are problems with that approach:
* Need to create a new file descriptor for each callback
* The IO Manger thread(s) become a bottleneck
* More potential for things to go wrong, e.g. throwing an exception in
  an IO Manager callback kills the IO Manager thread.

Test Plan: validate; new unit tests

Reviewers: niteria, erikd, ezyang, bgamari, austin, hvr

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2501

A folow-up to D2521 (which addressed #12583), where the `Outputable` `ppr`
output was tweaked to display a list comprehension with only one `Stmt` as
`[Foo]` instead of `[Foo|]` (which isn't valid Haskell). I forgot to update
the corresponding code in `Language.Haskell.TH.Ppr` which pretty-prints
`CompE`, however, so this commit takes care of that.

Summary:
Standalone-derived `Ix` instances would panic on GADTs with exactly
one constructor, since the list of fields was being passed to a function that
uses `foldl1` in order to generate an implementation for `inRange`. This adds a
simple check that makes `inRange` be `True` whenever a product type has no
fields.

Fixes #12583.

Test Plan: make test TEST=12583

Reviewers: simonpj, austin, bgamari

Reviewed By: bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2521

GHC Trac Issues: #12583

You can now just use `mkMatchGroup`.

Summary:
The generated documentation for thhe Foreign.C.Types
module is generated based on the platform which ran Haddock.

This is generating incorrect types for e.g. Windows.

Add a disclaimer to the top of the page to ask people to
keep this in mind.

Test Plan: make documentation and inspect Haddock

Reviewers: erikd, austin, hvr, bgamari

Reviewed By: erikd

Subscribers: RyanGlScott, #ghc_windows_task_force, thomie

Differential Revision: https://phabricator.haskell.org/D2523

GHC Trac Issues: #12586

Summary:
D2461 seemed to (inadvertently, I think) add the
`-flocal-ghci-history` flag to the list of `defaultFlags` that are enabled
automatically. As a result, every invocation of `ghci` caused a local GHCi
history to be saved to the current directory, which probably shouldn't be the
default.

Test Plan:
Run `ghci`, observe the lack of a `.ghci_history` file in your
working directory

Reviewers: austin, thomie, bgamari

Reviewed By: bgamari

Subscribers: ak3n

Differential Revision: https://phabricator.haskell.org/D2520

GHC Trac Issues: #9089

bitonic authored 8 years ago and Tamar Christina committed 8 years ago

Summary:
We stumbled upon a case where an external library (OpenCL) does not work
if a specific address (0x200000000) is taken.

It so happens that `osReserveHeapMemory` starts trying to mmap at 0x200000000:

```
        void *hint = (void*)((W_)8 * (1 << 30) + attempt * BLOCK_SIZE);
        at = osTryReserveHeapMemory(*len, hint);
```

This makes it impossible to use Haskell programs compiled with GHC 8
with C functions that use OpenCL.

See this example ​https://github.com/chpatrick/oclwtf for a repro.

This patch allows the user to work around this kind of behavior outside
our control by letting the user override the starting address through an
RTS command line flag.

Reviewers: bgamari, Phyx, simonmar, erikd, austin

Reviewed By: Phyx, simonmar

Subscribers: rwbarton, thomie

Differential Revision: https://phabricator.haskell.org/D2513

Summary:
The external interpreter is launched by calling
'System.Process.createProcess' with a 'CreateProcess' parameter.

The current value for this has the 'std_in', 'std_out' and 'std_err'
fields use the default of 'Inherit', meaning that the remote interpreter
shares the stdio with the original ghc/ghci process.

This patch introduces a new hook to the DynFlags, which has an
opportunity to override the 'CreateProcess' fields, launch the process,
and retrieve the stdio handles actually used.

So if a ghci external interpreter session is launched from the GHC API
the stdio can be redirected if required, which is useful for tooling/IDE
integration.

Test Plan: ./validate

Reviewers: austin, hvr, simonmar, bgamari

Reviewed By: simonmar, bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2518

Fixes readdir validation error (fixes #12572).

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Test Plan: none

Reviewers: austin, niteria, bgamari

Reviewed By: niteria

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2514

GHC Trac Issues: #12485

Ben Gamari authored 8 years ago and Ben Gamari committed 8 years ago

Test Plan: Read it

Reviewers: dfeuer, austin

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2515

GHC Trac Issues: #11691

Ben Gamari authored 8 years ago and Ben Gamari committed 8 years ago

Test Plan: Validate

Reviewers: austin

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2517

GHC Trac Issues: #11433

takano-akio authored 8 years ago and Ben Gamari committed 8 years ago

This change should close #11108 by fixing the test case.

This commit fixes two issues:

* Make sure that each weak pointer we allocate has a constructor as the
  key, not a thunk. A failure to do so meant these weak pointers died
  prematurely on the 'ghci' WAY.

* Don't print anything in the finalizer, because they are not guaranteed
  to run.

Test Plan: validate

Reviewers: austin, simonmar, erikd, bgamari

Reviewed By: erikd, bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2512

GHC Trac Issues: #11108

Ben Gamari authored 8 years ago and Ben Gamari committed 8 years ago

As reported in #12555 this code was terribly broken. Sadly, Autoconf was
none-the-wiser. Thanks to @rwbarton for pointing this out.

Test Plan: Test with libdw version newer and older and 0.158

Reviewers: hvr, austin, rwbarton

Reviewed By: rwbarton

Subscribers: thomie, rwbarton, erikd

Differential Revision: https://phabricator.haskell.org/D2510

GHC Trac Issues: #12555

Summary:
For some inexplicable reason, the `Generic` instance in
`perf/compiler/T5642` is written out entirely by hand. This is not only
strange, since Trac #5642 is about derived `Generic` instances, but it also
annoying to maintain, since it requires manually changing a bunch of code
whenever the algorithm behind `deriving Generic` changes. (See D2304 for a
recent example of this.)

It seems more sensible to just derive the `Generic` instance. It shifts the
goalposts of what allocations we're measuring a bit, since we no longer have
to parse a large amount of code (and as a knock-on effect, the allocations go
down a bit). But I think this program is morally equivalent to what we were
benchmarking before, so it's not too unreasonable to change.

Test Plan: make test TEST=T5642

Reviewers: austin, thomie, bgamari

Reviewed By: bgamari

Differential Revision: https://phabricator.haskell.org/D2511

GHC Trac Issues: #5642

prokhorenkov authored 8 years ago and Ben Gamari committed 8 years ago

Reviewers: simonpj, bgamari, RyanGlScott, austin

Reviewed By: simonpj

Subscribers: nomeata, simonpj, thomie

Differential Revision: https://phabricator.haskell.org/D2502

GHC Trac Issues: #10858

Test Plan: Corrected a few tests to include the new message.

Reviewers: goldfire, austin, bgamari

Reviewed By: bgamari

Subscribers: goldfire, thomie

Differential Revision: https://phabricator.haskell.org/D2484

GHC Trac Issues: #12546

takano-akio authored 8 years ago and Ben Gamari committed 8 years ago

This implements #5615 for divInt# and modInt#.

I also included rules to do constant-folding when the both arguments
are known.

Test Plan: validate

Reviewers: austin, simonmar, bgamari

Reviewed By: bgamari

Subscribers: hvr, thomie

Differential Revision: https://phabricator.haskell.org/D2486

GHC Trac Issues: #5615

Summary:
Module finalizer could call addTopDecls, however, the declarations
added in this fashion were ignored. This patch makes sure to rename,
type check and incorporate this declarations.

Because a declaration may include a splice which calls addModFinalizer,
the list of finalizers is repeteadly checked after adding declarations
until no more finalizers remain.

Test Plan: ./validate

Reviewers: bgamari, goldfire, simonpj, austin

Reviewed By: bgamari, simonpj

Subscribers: simonmar, mboes, thomie

Differential Revision: https://phabricator.haskell.org/D2505

GHC Trac Issues: #12559

The 'return () >>' hack was added in commit
    commit ac88f113
    Date:   Tue Jul 26 12:14:03 2005 +0000

Nowadays it has no effect on generated Core on -O1/-O2
and slightly bloats Core on -O0.

Signed-off-by: Sergei Trofimovich <siarheit@google.com>

It's a complementary change to
    a48de37d
    restore -fmax-worker-args handling (Trac #11565)

I don't have a small example but I've noticed another
discrepancy when was profiling GHC for performance

    cmmExprNative :: ReferenceKind -> CmmExpr -> CmmOptM CmmExpr

was specialised by 'spec_one' down to a function with arity 159.
As a result 'perf record' pointed at it as at slowest
function in whole ghc library.

I've extended -fmax-worker-args effect to 'spec_one'
as it does the same worker/wrapper split to push
arguments to the heap.

The change decreases heap usage on a synth.bash benchmark
(Trac #9221) from 67G down to 64G (-4%). Benchmark runtime
decreased from 14.5 s down to 14.s (-7%).

Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Reviewers: ezyang, simonpj, austin, goldfire, bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2507

GHC Trac Issues: #11565

Signed-off-by: Sergei Trofimovich <siarheit@google.com>

Summary: Also comment on the need to use stgMallocBytes in StaticPtrTable.c.

Test Plan: ./validate

Reviewers: erikd, austin, bgamari, simonmar

Reviewed By: simonmar

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2506