Commit Graph

80 Commits

Author SHA1 Message Date
Javed Absar
895d00e6b0 Fix incorrect comment in machine-scheduler
The example code incorrectly invokes ScheduleDAGMI wherein from context
it is clear it intends to invoke ScheduleDAGMILive actually.

Reviewed by: Andrew Trick
Differential Revision: https://reviews.llvm.org/D34675

llvm-svn: 306424
2017-06-27 16:49:45 +00:00
Sam Clegg
b5685bbe56 Mark dump() methods as const. NFC
Add const qualifier to any dump() method where adding one
was trivial.

Differential Revision: https://reviews.llvm.org/D34481

llvm-svn: 305963
2017-06-21 22:19:17 +00:00
Eugene Zelenko
8839504c59 [CodeGen] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 304495
2017-06-01 23:25:02 +00:00
Eugene Zelenko
8c806a2ad0 [CodeGen] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 295893
2017-02-22 22:32:51 +00:00
Evandro Menezes
f3c547dbf4 [CodeGen] Move MacroFusion to the target
This patch moves the class for scheduling adjacent instructions,
MacroFusion, to the target.

In AArch64, it also expands the fusion to all instructions pairs in a
scheduling block, beyond just among the predecessors of the branch at the
end.

Differential revision: https://reviews.llvm.org/D28489

llvm-svn: 293737
2017-02-01 02:54:34 +00:00
Matthias Braun
ce011a4aed MachineScheduler: Export function to construct "default" scheduler.
This makes the createGenericSchedLive() function that constructs the
default scheduler available for the public API. This should help when
you want to get a scheduler and the default list of DAG mutations.

This also shrinks the list of default DAG mutations:
{Load|Store}ClusterDAGMutation and MacroFusionDAGMutation are no longer
added by default. Targets can easily add them if they need them. It also
makes it easier for targets to add alternative/custom macrofusion or
clustering mutations while staying with the default
createGenericSchedLive(). It also saves the callback back and forth in
TargetInstrInfo::enableClusterLoads()/enableClusterStores().

Differential Revision: https://reviews.llvm.org/D26986

llvm-svn: 288057
2016-11-28 20:11:54 +00:00
Matthias Braun
de89474ce3 ScheduleDAGInstrs: Move VRegUses to ScheduleDAGMILive; NFCI
Push VRegUses/collectVRegUses() down the class hierarchy towards its
only user ScheduleDAGMILive.

NFCI: The initialization of the map happens at a later point but that
should not matter.

This is in preparation to allow DAG mutators to merge nodes, which
relies on this map getting computed later.

llvm-svn: 286654
2016-11-11 22:37:31 +00:00
Matthias Braun
4741c1e622 ScheduleDAGInstrs: Add condjump deps to addSchedBarrierDeps()
addSchedBarrierDeps() is supposed to add use operands to the ExitSU
node. The current implementation adds uses for calls/barrier instruction
and the MBB live-outs in all other cases. The use
operands of conditional jump instructions were missed.

Also added code to macrofusion to set the latencies between nodes to
zero to avoid problems with the fusing nodes lingering around in the
pending list now.

Differential Revision: https://reviews.llvm.org/D25140

llvm-svn: 286544
2016-11-11 01:34:21 +00:00
Eugene Zelenko
7aa413a524 Fix some Clang-tidy modernize-use-default and readability-redundant-member-init and Include What You Use warnings; other minor fixes.
Differential revision: https://reviews.llvm.org/D26087

llvm-svn: 286484
2016-11-10 18:02:34 +00:00
Matthias Braun
650e8168dc MachineScheduler: Slightly simplify release node
llvm-svn: 282201
2016-09-22 21:39:56 +00:00
Matthias Braun
b1e06b237f MachineScheduler: Remove ineffective heuristic; NFC
Currently all nodes get added to the NextSU list when they are released,
so any candidate must be in that list, making the heuristic ineffective.
Remove it for now, we can add it back later in a working fashion if
necessary.

llvm-svn: 282200
2016-09-22 21:39:52 +00:00
Tom Stellard
7a22aa0ce1 MachineScheduler: Add constructor functions for the DAGMutations
Summary: This way they can be re-used by target-specific schedulers.

Reviewers: atrick, MatzeB, kparzysz

Subscribers: kparzysz, llvm-commits, MatzeB

Differential Revision: https://reviews.llvm.org/D23678

llvm-svn: 279305
2016-08-19 19:59:18 +00:00
Tom Stellard
09f3e73485 MachineScheduler: Make some GenericScheduler member variables protected
Summary: We will need these in AMDGPU's new SchedStrategy implmentation.

Reviewers: MatzeB, atrick

Subscribers: llvm-commits, MatzeB

Differential Revision: https://reviews.llvm.org/D23679

llvm-svn: 279270
2016-08-19 16:44:32 +00:00
David Majnemer
85242fb9f9 Use the range variant of find instead of unpacking begin/end
If the result of the find is only used to compare against end(), just
use is_contained instead.

No functionality change is intended.

llvm-svn: 278433
2016-08-11 22:21:41 +00:00
Duncan P. N. Exon Smith
c2d816d704 Target: Remove unused arguments from overrideSchedPolicy, NFC
TargetSubtargetInfo::overrideSchedPolicy takes two MachineInstr*
arguments (begin and end) that invite implicit conversions from
MachineInstrBundleIterator.  One option would be to change their type to
an iterator, but since they don't seem to have been used since the API
was added in 2010, I'm deleting the dead code.

llvm-svn: 274304
2016-07-01 00:23:27 +00:00
Matthias Braun
97ee40fb74 MachineScheduler: Remember top/bottom choice in bidirectional scheduling
Remember the last choice for the top/bottom scheduling boundary in
bidirectional scheduling mode. The top choice should not change if we
schedule at the bottom and vice versa.

This allows us to improve compiletime: We only recalculate the best pick
for one border and re-use the cached top-pick from the other border.

Differential Revision: http://reviews.llvm.org/D19350

llvm-svn: 273766
2016-06-25 02:03:36 +00:00
Matthias Braun
73106790a8 MachineScheduler: Fully compare top/bottom candidates
In bidirectional scheduling this gives more stable results than just
comparing the "reason" fields of the top/bottom node because the reason
field may be higher depending on what other nodes are in the queue.

Differential Revision: http://reviews.llvm.org/D19401

llvm-svn: 273755
2016-06-25 00:23:00 +00:00
Matthias Braun
96f0c83689 MachineScheduler: Introduce ONLY1 reason to improve debug output
llvm-svn: 271058
2016-05-27 22:14:26 +00:00
Krzysztof Parzyszek
f555db9453 Reset the TopRPTracker's position in ScheduleDAGMILive::initQueues
ScheduleDAGMI::initQueues changes the RegionBegin to the first non-debug
instruction. Since it does not track register pressure, it does not affect
any RP trackers. ScheduleDAGMILive inherits initQueues from ScheduleDAGMI,
and it does reset the TopTPTracker in its schedule method. Any derived,
target-specific scheduler will need to do it as well, but the TopRPTracker
is only exposed as a "const" object to derived classes. Without the ability
to modify the tracker directly, this leaves a derived scheduler with a
potential of having the TopRPTracker out-of-sync with the CurrentTop.

The symptom of the problem:
  void llvm::ScheduleDAGMILive::scheduleMI(llvm::SUnit *, bool):
  Assertion `TopRPTracker.getPos() == CurrentTop && "out of sync"' failed.

Differential Revision: http://reviews.llvm.org/D19438

llvm-svn: 267918
2016-04-28 19:17:44 +00:00
Matthias Braun
0f77e38f18 MachineScheduler: Move code to initialize a Candidate out of tryCandidate(); NFC
llvm-svn: 267191
2016-04-22 19:10:15 +00:00
Krzysztof Parzyszek
c3a6777f22 Add DAG mutation interface to the post-RA scheduler
Differential Revision: http://reviews.llvm.org/D17868

llvm-svn: 262774
2016-03-05 15:45:23 +00:00
Matthias Braun
3f5b3cdbf1 MachineScheduler: Allow independent scheduling of sub register defs
Note that this is disabled by default and still requires a patch to
handleMove() which is not upstreamed yet.

If the TrackLaneMasks policy/strategy is enabled the MachineScheduler
will build a schedule graph where definitions of independent
subregisters are no longer serialised.

Implementation comments:
- Without lane mask tracking a sub register def also counts as a use
  (except for the first one with the read-undef flag set), with lane
  mask tracking enabled this is no longer the case.
- Pressure Diffs where previously maintained per definition of a
  vreg with the help of the SSA information contained in the
  LiveIntervals.  With lanemask tracking enabled we cannot do this
  anymore and instead change the pressure diffs for all uses of the vreg
  as it becomes live/dead.  For this changed style to work correctly we
  ignore uses of instructions that define the same register again: They
  won't affect register pressure.
- With lanemask tracking we remove all read-undef flags from
  sub register defs when building the graph and re-add them later when
  all vreg lanes have become dead.

Differential Revision: http://reviews.llvm.org/D14969

llvm-svn: 258259
2016-01-20 00:23:32 +00:00
Matthias Braun
895450b36f RegisterPressure: Make liveness tracking subregister aware
Differential Revision: http://reviews.llvm.org/D14968

llvm-svn: 258258
2016-01-20 00:23:26 +00:00
Matthias Braun
54aeb74db9 ScheduleDAGInstrs: Move LiveIntervals field to ScheduleDAGMI
Now that ScheduleDAGInstrs doesn't need it anymore we can move the field
down the class hierarcy to ScheduleDAGMI.

llvm-svn: 254759
2015-12-04 19:54:24 +00:00
Matthias Braun
a75cf73a70 ScheduleDAGInstrs: Remove IsPostRA flag; NFC
ScheduleDAGInstrs doesn't behave differently before or after register
allocation. It was only used in a method of MachineSchedulerBase which
behaved differently in MachineScheduler/PostMachineScheduler. Change
this to let MachineScheduler/PostMachineScheduler just pass in a
parameter to that function.

The order of the LiveIntervals* and bool RemoveKillFlags paramters have
been switched to make out-of-tree code fail instead of unintentionally
passing a value intended for the IsPostRA flag to the (previously
following and default initialized) RemoveKillFlags.

Differential Revision: http://reviews.llvm.org/D14245

llvm-svn: 251883
2015-11-03 01:53:29 +00:00
Matthias Braun
75235b7d5c Revert "ScheduleDAGInstrs: Remove IsPostRA flag"
It broke 3 arm testcases.

This reverts commit r251608.

llvm-svn: 251615
2015-10-29 05:06:41 +00:00
Matthias Braun
2ae11dd8a3 ScheduleDAGInstrs: Remove IsPostRA flag
This was a layering violation in ScheduleDAGInstrs (and
MachineSchedulerBase) they both shouldn't know directly whether they are
used by the PostMachineScheduler or the MachineScheduler.

llvm-svn: 251608
2015-10-29 03:57:24 +00:00
Matthias Braun
b42deafbca MachineScheduler: Add a way to disable the 'ReduceLatency' heuristic
llvm-svn: 251037
2015-10-22 18:07:31 +00:00
James Y Knight
6a6ee2cd7f Make MachineScheduler debug output less confusing.
At least...a little bit.

llvm-svn: 248020
2015-09-18 18:52:20 +00:00
Chandler Carruth
d7003090ac [PM/AA] Rebuild LLVM's alias analysis infrastructure in a way compatible
with the new pass manager, and no longer relying on analysis groups.

This builds essentially a ground-up new AA infrastructure stack for
LLVM. The core ideas are the same that are used throughout the new pass
manager: type erased polymorphism and direct composition. The design is
as follows:

- FunctionAAResults is a type-erasing alias analysis results aggregation
  interface to walk a single query across a range of results from
  different alias analyses. Currently this is function-specific as we
  always assume that aliasing queries are *within* a function.

- AAResultBase is a CRTP utility providing stub implementations of
  various parts of the alias analysis result concept, notably in several
  cases in terms of other more general parts of the interface. This can
  be used to implement only a narrow part of the interface rather than
  the entire interface. This isn't really ideal, this logic should be
  hoisted into FunctionAAResults as currently it will cause
  a significant amount of redundant work, but it faithfully models the
  behavior of the prior infrastructure.

- All the alias analysis passes are ported to be wrapper passes for the
  legacy PM and new-style analysis passes for the new PM with a shared
  result object. In some cases (most notably CFL), this is an extremely
  naive approach that we should revisit when we can specialize for the
  new pass manager.

- BasicAA has been restructured to reflect that it is much more
  fundamentally a function analysis because it uses dominator trees and
  loop info that need to be constructed for each function.

All of the references to getting alias analysis results have been
updated to use the new aggregation interface. All the preservation and
other pass management code has been updated accordingly.

The way the FunctionAAResultsWrapperPass works is to detect the
available alias analyses when run, and add them to the results object.
This means that we should be able to continue to respect when various
passes are added to the pipeline, for example adding CFL or adding TBAA
passes should just cause their results to be available and to get folded
into this. The exception to this rule is BasicAA which really needs to
be a function pass due to using dominator trees and loop info. As
a consequence, the FunctionAAResultsWrapperPass directly depends on
BasicAA and always includes it in the aggregation.

This has significant implications for preserving analyses. Generally,
most passes shouldn't bother preserving FunctionAAResultsWrapperPass
because rebuilding the results just updates the set of known AA passes.
The exception to this rule are LoopPass instances which need to preserve
all the function analyses that the loop pass manager will end up
needing. This means preserving both BasicAAWrapperPass and the
aggregating FunctionAAResultsWrapperPass.

Now, when preserving an alias analysis, you do so by directly preserving
that analysis. This is only necessary for non-immutable-pass-provided
alias analyses though, and there are only three of interest: BasicAA,
GlobalsAA (formerly GlobalsModRef), and SCEVAA. Usually BasicAA is
preserved when needed because it (like DominatorTree and LoopInfo) is
marked as a CFG-only pass. I've expanded GlobalsAA into the preserved
set everywhere we previously were preserving all of AliasAnalysis, and
I've added SCEVAA in the intersection of that with where we preserve
SCEV itself.

One significant challenge to all of this is that the CGSCC passes were
actually using the alias analysis implementations by taking advantage of
a pretty amazing set of loop holes in the old pass manager's analysis
management code which allowed analysis groups to slide through in many
cases. Moving away from analysis groups makes this problem much more
obvious. To fix it, I've leveraged the flexibility the design of the new
PM components provides to just directly construct the relevant alias
analyses for the relevant functions in the IPO passes that need them.
This is a bit hacky, but should go away with the new pass manager, and
is already in many ways cleaner than the prior state.

Another significant challenge is that various facilities of the old
alias analysis infrastructure just don't fit any more. The most
significant of these is the alias analysis 'counter' pass. That pass
relied on the ability to snoop on AA queries at different points in the
analysis group chain. Instead, I'm planning to build printing
functionality directly into the aggregation layer. I've not included
that in this patch merely to keep it smaller.

Note that all of this needs a nearly complete rewrite of the AA
documentation. I'm planning to do that, but I'd like to make sure the
new design settles, and to flesh out a bit more of what it looks like in
the new pass manager first.

Differential Revision: http://reviews.llvm.org/D12080

llvm-svn: 247167
2015-09-09 17:55:00 +00:00
Hans Wennborg
34fee45808 Fix -Wextra-semi warnings.
Patch by Eugene Zelenko!

Differential Revision: http://reviews.llvm.org/D11400

llvm-svn: 242930
2015-07-22 20:46:11 +00:00
Alexander Kornienko
71412ece39 Use 'override/final' instead of 'virtual' for overridden methods
The patch is generated using clang-tidy misc-use-override check.

This command was used:

  tools/clang/tools/extra/clang-tidy/tool/run-clang-tidy.py \
    -checks='-*,misc-use-override' -header-filter='llvm|clang' \
    -j=32 -fix -format

http://reviews.llvm.org/D8925

llvm-svn: 234679
2015-04-11 02:11:45 +00:00
Chandler Carruth
0b619fcc8e [cleanup] Re-sort all the #include lines in LLVM using
utils/sort_includes.py.

I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.

llvm-svn: 225974
2015-01-14 11:23:27 +00:00
Alexey Samsonov
08af4466dd Cleanup: Delete seemingly unused reference to MachineDominatorTree from ScheduleDAGInstrs.
llvm-svn: 216124
2014-08-20 20:57:26 +00:00
Alexey Samsonov
d47abf2d7c Fix null reference creation in ScheduleDAGInstrs constructor call.
Both MachineLoopInfo and MachineDominatorTree may be null in ScheduleDAGMI
constructor call. It is undefined behavior to take references to these values.

This bug is reported by UBSan.

llvm-svn: 216118
2014-08-20 19:36:05 +00:00
Alp Toker
62b822cb61 Move remaining LLVM_ENABLE_DUMP conditionals out of the headers
This macro is sometimes defined manually but isn't (and doesn't need to be) in
llvm-config.h so shouldn't appear in the headers, likewise NDEBUG.

Instead switch them over to LLVM_DUMP_METHOD on the definitions.

llvm-svn: 212130
2014-07-01 21:19:13 +00:00
Andrew Trick
bdb0601a15 Fix the MachineScheduler's logic for updating ready times for in-order.
Now the scheduler updates a node's ready time as soon as it is
scheduled, before releasing dependent nodes. There was a reason I
didn't do this initially but it no longer applies.

A53 is in-order and was running into an issue where nodes where added
to the readyQ too early. That's now fixed.

This also makes it easier for custom scheduling strategies to build
heuristics based on the actual cycles that the node was scheduled at.

The only impact on OOO (sandybridge/cyclone) is that ready times will
be slightly more accurate. I didn't measure any significant regressions.

llvm-svn: 210390
2014-06-07 01:48:43 +00:00
Andrew Trick
ba65eed5cb Move GenericScheduler and PostGenericScheduler into a header.
These were not exposed previously because I didn't want out-of-tree
targets to be too dependent on their internals. They can be reused for
a very wide variety of processors with casual scheduling needs without
exposing the classes by instead using hooks defined in
MachineSchedPolicy (we can add more if needed). When targets are more
aggressively tuned or want to provide custom heuristics, they can
define their own MachineSchedStrategy. I tend to think this is better
once you start customizing heuristics because you can copy over only
what you need. I don't think that layering heuristics generally works
well.

However, Arch64 targets now want to reuse the Generic scheduling logic
but also provide extensions. I don't see much harm in exposing the
Generic scheduling classes with a major caveat: these scheduling
strategies may change in the future without validating performance on
less mainstream processors. If you want to be immune from changes,
just define your own MachineSchedStrategy.

llvm-svn: 210166
2014-06-04 07:06:18 +00:00
David Blaikie
3fde01a358 Use unique_ptr to manage objects owned by the ScheduleDAGMI.
llvm-svn: 206784
2014-04-21 20:32:32 +00:00
Craig Topper
30281a67fb [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr.
llvm-svn: 206142
2014-04-14 00:51:57 +00:00
Craig Topper
b3cfc7916b [C++11] Add 'override' keyword to virtual methods that override their base class.
llvm-svn: 203220
2014-03-07 09:26:03 +00:00
Craig Topper
b0056a4ca7 Switch all uses of LLVM_OVERRIDE to just use 'override' directly.
llvm-svn: 202621
2014-03-02 09:09:27 +00:00
Andrew Trick
cbd3ee31c7 Move the PostRA scheduler's fixupKills function for reuse.
llvm-svn: 198121
2013-12-28 21:56:55 +00:00
Andrew Trick
c4eb826f6c Factor MI-Sched in preparation for post-ra scheduling support.
Factor the MachineFunctionPass into MachineSchedulerBase.

Split the DAG class into ScheduleDAGMI and SchedulerDAGMILive.

llvm-svn: 198119
2013-12-28 21:56:47 +00:00
Andrew Trick
2ac3f8f326 Factor out the SchedRemainder/SchedBoundary from GenericScheduler strategy.
These helper classes take care of the book-keeping the drives the
GenericScheduler heuristics. It is likely that developers writing
target-specific schedulers that work similarly to GenericScheduler
will want to use these helpers too. The immediate goal is to develop a
GenericPostScheduler that can run in place of the old PostRAScheduler,
but will use the new machine model.

No functionality change intended.

llvm-svn: 196643
2013-12-07 05:59:44 +00:00
Juergen Ributzka
5357a6d64b [weak vtables] Remove a bunch of weak vtables
This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file. The memory leaks in this version have been fixed. Thanks
Alexey for pointing them out.

Differential Revision: http://llvm-reviews.chandlerc.com/D2068

Reviewed by Andy

llvm-svn: 195064
2013-11-19 00:57:56 +00:00
Alexey Samsonov
3bfef6bdb6 Revert r194865 and r194874.
This change is incorrect. If you delete virtual destructor of both a base class
and a subclass, then the following code:
  Base *foo = new Child();
  delete foo;
will not cause the destructor for members of Child class. As a result, I observe
plently of memory leaks. Notable examples I investigated are:
ObjectBuffer and ObjectBufferStream, AttributeImpl and StringSAttributeImpl.

llvm-svn: 194997
2013-11-18 09:31:53 +00:00
Juergen Ributzka
ee3af15269 [weak vtables] Remove a bunch of weak vtables
This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file.

Differential Revision: http://llvm-reviews.chandlerc.com/D2068

Reviewed by Andy

llvm-svn: 194865
2013-11-15 22:34:48 +00:00
Andrew Trick
439918c874 Allow subtarget selection of the default MachineScheduler and document the interface.
The global registry is used to allow command line override of the
scheduler selection, but does not work well as the normal selection
API. For example, the same LLVM process should be able to target
multiple targets or subtargets.

llvm-svn: 191071
2013-09-20 05:14:41 +00:00
Andrew Trick
0d8da69006 mi-sched: cleanup register pressure update, remove a FIXME.
llvm-svn: 190181
2013-09-06 17:32:47 +00:00