Commit Graph

291 Commits

Author SHA1 Message Date
Matthias Braun 5f8492e2ce MachineScheduler: Slightly simplify release node
llvm-svn: 282201
2016-09-22 21:39:56 +00:00
Matthias Braun 46533e614b 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 68726a5359 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
Duncan P. N. Exon Smith dcbce9c391 CodeGen: Avoid dereferencing end() when unconstifying iterators
Rather than doing a funny dance that relies on dereferencing end() not
crashing, add some API to MachineInstrBundleIterator to get a non-const
version of the iterator.

llvm-svn: 278870
2016-08-16 23:34:07 +00:00
Duncan P. N. Exon Smith 38eea4a76f CodeGen: Avoid dereferencing end() in MachineScheduler
Check MachineInstr::isDebugValue for the same instruction as we're
calling isSchedBoundary, avoiding the possibility of dereferencing
end().

This is a functionality change even when I!=end().  Matthias had a look
and agrees this is the right resolution (as opposed to checking for
end()).

This is triggered by a huge number of tests, but they happen to
magically pass right now.  I found this because WIP patches for PR26753
convert them into crashes.

llvm-svn: 278394
2016-08-11 20:03:09 +00:00
Duncan P. N. Exon Smith 632987296f 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
Duncan P. N. Exon Smith 9cfc75c214 CodeGen: Use MachineInstr& in TargetInstrInfo, NFC
This is mostly a mechanical change to make TargetInstrInfo API take
MachineInstr& (instead of MachineInstr* or MachineBasicBlock::iterator)
when the argument is expected to be a valid MachineInstr.  This is a
general API improvement.

Although it would be possible to do this one function at a time, that
would demand a quadratic amount of churn since many of these functions
call each other.  Instead I've done everything as a block and just
updated what was necessary.

This is mostly mechanical fixes: adding and removing `*` and `&`
operators.  The only non-mechanical change is to split
ARMBaseInstrInfo::getOperandLatencyImpl out from
ARMBaseInstrInfo::getOperandLatency.  Previously, the latter took a
`MachineInstr*` which it updated to the instruction bundle leader; now,
the latter calls the former either with the same `MachineInstr&` or the
bundle leader.

As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.

Note: I updated WebAssembly, Lanai, and AVR (despite being
off-by-default) since it turned out to be easy.  I couldn't run tests
for AVR since llc doesn't link with it turned on.

llvm-svn: 274189
2016-06-30 00:01:54 +00:00
Matthias Braun cc676c47a3 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 6ad3d05b68 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 4d624ae0cb MachineScheduler: Followup to debug message changes
Do not dump intermediate state of the pending queue anymore now that we
always dump the final state before picking.

llvm-svn: 273618
2016-06-23 21:43:28 +00:00
Matthias Braun d29d31e30e MachineScheduler: Improve debug messages
Consistenly display available and pending queues immediately before the
scheduling choice is done.

llvm-svn: 273615
2016-06-23 21:27:38 +00:00
Matthias Braun f9acacaa92 CodeGen: Refactor renameDisconnectedComponents() as a pass
Refactor LiveIntervals::renameDisconnectedComponents() to be a pass.
Also change the name to "RenameIndependentSubregs":

- renameDisconnectedComponents() worked on a MachineFunction at a time
  so it is a natural candidate for a machine function pass.

- The algorithm is testable with a .mir test now.

- This also fixes a problem where the lazy renaming as part of the
  MachineScheduler introduced IMPLICIT_DEF instructions after the number
  of a nodes in a region were counted leading to a mismatch.

Differential Revision: http://reviews.llvm.org/D20507

llvm-svn: 271345
2016-05-31 22:38:06 +00:00
Matthias Braun 49cb6e909d MachineScheduler: Introduce ONLY1 reason to improve debug output
llvm-svn: 271058
2016-05-27 22:14:26 +00:00
Matthias Braun 858d1df246 LiveIntervalAnalysis: Fix missing defs in renameDisconnectedComponents().
Fix renameDisconnectedComponents() creating vreg uses that can be
reached from function begin withouthaving a definition (or explicit
live-in). Fix this by inserting IMPLICIT_DEF instruction before
control-flow joins as necessary.

Removes an assert from MachineScheduler because we may now get
additional IMPLICIT_DEF when preparing the scheduling policy.

This fixes the underlying problem of http://llvm.org/PR27705

llvm-svn: 270259
2016-05-20 19:46:13 +00:00
Matthias Braun 31d19d43c7 CodeGen: Move TargetPassConfig from Passes.h to an own header; NFC
Many files include Passes.h but only a fraction needs to know about the
TargetPassConfig class. Move it into an own header. Also rename
Passes.cpp to TargetPassConfig.cpp while we are at it.

llvm-svn: 269011
2016-05-10 03:21:59 +00:00
Krzysztof Parzyszek 7ea9a529aa 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
Andrew Kaylor aa641a5171 Re-commit optimization bisect support (r267022) without new pass manager support.
The original commit was reverted because of a buildbot problem with LazyCallGraph::SCC handling (not related to the OptBisect handling).

Differential Revision: http://reviews.llvm.org/D19172

llvm-svn: 267231
2016-04-22 22:06:11 +00:00
Matthias Braun 4f57377c68 MachineScheduler: Move code to initialize a Candidate out of tryCandidate(); NFC
llvm-svn: 267191
2016-04-22 19:10:15 +00:00
Matthias Braun 6493bc2b97 MachineScheduler: Limit the size of the ready list.
Avoid quadratic complexity in unusually large basic blocks by limiting
the size of the ready lists.

Differential Revision: http://reviews.llvm.org/D19349

llvm-svn: 267189
2016-04-22 19:09:17 +00:00
Vedant Kumar 6013f45f92 Revert "Initial implementation of optimization bisect support."
This reverts commit r267022, due to an ASan failure:

  http://lab.llvm.org:8080/green/job/clang-stage2-cmake-RgSan_check/1549

llvm-svn: 267115
2016-04-22 06:51:37 +00:00
Andrew Kaylor f0f279291c Initial implementation of optimization bisect support.
This patch implements a optimization bisect feature, which will allow optimizations to be selectively disabled at compile time in order to track down test failures that are caused by incorrect optimizations.

The bisection is enabled using a new command line option (-opt-bisect-limit).  Individual passes that may be skipped call the OptBisect object (via an LLVMContext) to see if they should be skipped based on the bisect limit.  A finer level of control (disabling individual transformations) can be managed through an addition OptBisect method, but this is not yet used.

The skip checking in this implementation is based on (and replaces) the skipOptnoneFunction check.  Where that check was being called, a new call has been inserted in its place which checks the bisect limit and the optnone attribute.  A new function call has been added for module and SCC passes that behaves in a similar way.

Differential Revision: http://reviews.llvm.org/D19172

llvm-svn: 267022
2016-04-21 17:58:54 +00:00
Matthias Braun b550b765bd MachineSched: Cleanup; NFC
llvm-svn: 266946
2016-04-21 01:54:13 +00:00
Mehdi Amini b550cb1750 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
Jun Bum Lim 4c5bd58ebe [MachineScheduler]Add support for store clustering
Perform store clustering just like load clustering. This change add
StoreClusterMutation in machine-scheduler. To control StoreClusterMutation,
added enableClusterStores() in TargetInstrInfo.h. This is enabled only on
AArch64 for now.

This change also add support for unscaled stores which were not handled in
getMemOpBaseRegImmOfs().

llvm-svn: 266437
2016-04-15 14:58:38 +00:00
Matthias Braun 7511abd5c1 MachineScheduler: Ignore COPYs with undef/dead op in CopyConstrain mutation.
There is no problem with the code today, but the fix will avoid a crash
in test/CodeGen/AMDGPU/subreg-coalescer-undef-use.ll once the
DetectDeadLanes pass is added.

llvm-svn: 265351
2016-04-04 21:23:46 +00:00
Chad Rosier ac216fd9d5 [misched] Fix a truncation issue from r263021.
The truncation was causing the sorting algorithm to behave oddly when comparing
positive and negative offsets.  Fortunately, this doesn't currently happen in
practice and was exposed by a WIP.  Thus, I can't test this change now, but the
follow on patch will.

llvm-svn: 263255
2016-03-11 16:54:07 +00:00
Chad Rosier c27a18f39f [TII] Allow getMemOpBaseRegImmOfs() to accept negative offsets. NFC.
http://reviews.llvm.org/D17967

llvm-svn: 263021
2016-03-09 16:00:35 +00:00
Krzysztof Parzyszek 5c61d11a6d 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
Duncan P. N. Exon Smith be8f8c4478 CodeGen: Update LiveIntervalAnalysis API to use MachineInstr&, NFC
These parameters aren't expected to be null, so take them by reference.

llvm-svn: 262151
2016-02-27 20:14:29 +00:00
Duncan P. N. Exon Smith 3ac9cc6156 CodeGen: Take MachineInstr& in SlotIndexes and LiveIntervals, NFC
Take MachineInstr by reference instead of by pointer in SlotIndexes and
the SlotIndex wrappers in LiveIntervals.  The MachineInstrs here are
never null, so this cleans up the API a bit.  It also incidentally
removes a few implicit conversions from MachineInstrBundleIterator to
MachineInstr* (see PR26753).

At a couple of call sites it was convenient to convert to a range-based
for loop over MachineBasicBlock::instr_begin/instr_end, so I added
MachineBasicBlock::instrs.

llvm-svn: 262115
2016-02-27 06:40:41 +00:00
Chad Rosier 816a1ab9d9 MachineScheduler: Add a command line option to disable post scheduler.
llvm-svn: 258364
2016-01-20 23:08:32 +00:00
Chad Rosier 6338d7c390 MachineScheduler: Honor optnone functions in the pre-ra scheduler.
llvm-svn: 258363
2016-01-20 22:38:25 +00:00
Matthias Braun d4f6409dff 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 5d458617aa RegisterPressure: Make liveness tracking subregister aware
Differential Revision: http://reviews.llvm.org/D14968

llvm-svn: 258258
2016-01-20 00:23:26 +00:00
Tom Stellard 5ce530608f MachineScheduler: Add a target hook for deciding which RegPressure sets to
increase

Summary:
This patch adds a function called getRegPressureSetScore() to
TargetRegisterInfo.  The MachineScheduler uses this when comparing
instruction that increase the register pressure of different sets
to determine which set is safer to increase.

This hook is useful for GPU targets where the number of registers in the
class is not the best metric for determing which presser set is safer to
increase.

Future work may include adding more parameters to this function, like
for example, the current pressure level of the set or the amount that
the pressure will be increased/decreased.

Reviewers: qcolombet, escha, arsenm, atrick, MatzeB

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D14806

llvm-svn: 255795
2015-12-16 18:31:01 +00:00
Matthias Braun e6edd48d69 MachineScheduler: Print initial pressure in debug dump
llvm-svn: 253097
2015-11-13 22:30:31 +00:00
Matthias Braun 3b099db61d MachineScheduler: Improve debug output for "only one node in readyset"
When there is only 1 node left in the ready queue and it is picked call
the reason "ONLY1" instead of "NOCAND".

llvm-svn: 253096
2015-11-13 22:30:29 +00:00
Matthias Braun 9198c671e8 MachineScheduler: Add regpressure information to debug dump
llvm-svn: 252340
2015-11-06 20:59:02 +00:00
Matthias Braun 93563e7032 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 f2f194455f 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 dc7580aa88 MachineScheduler: Fix typo in debug message
Maybe I just missed the humor there ;-)

llvm-svn: 251609
2015-10-29 03:57:28 +00:00
Matthias Braun 7ffadd0087 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 b0c437bc76 MachineScheduler: Use ranged for and slightly simplify the code
llvm-svn: 251607
2015-10-29 03:57:17 +00:00
James Y Knight 14eedd189b Make the SelectionDAG graph printer use SDNode::PersistentId labels.
r248010 changed the -debug output to use short ids, but did not
similarly modify the graph printer. Change to be consistent, for ease of
cross-reference.

llvm-svn: 251465
2015-10-27 23:09:03 +00:00
Matthias Braun 61f4d6439c MachineScheduler: Add a way to disable the 'ReduceLatency' heuristic
llvm-svn: 251037
2015-10-22 18:07:31 +00:00
Duncan P. N. Exon Smith 5ec1568c9c CodeGen: Continue removing ilist iterator implicit conversions
llvm-svn: 249884
2015-10-09 19:40:45 +00:00
James Y Knight e72b0dbf97 Make MachineScheduler debug output less confusing.
At least...a little bit.

llvm-svn: 248020
2015-09-18 18:52:20 +00:00
Matthias Braun 3e86de1acb Revert "(HEAD -> master, origin/master, origin/HEAD) RegisterPressure: Move LiveInRegs/LiveOutRegs from RegisterPressure to PressureTracker"
This reverts commit r247943.

Accidental commit, code review was not finished yet.

llvm-svn: 247945
2015-09-17 21:12:24 +00:00
Matthias Braun 70eff2571f RegisterPressure: Move LiveInRegs/LiveOutRegs from RegisterPressure to PressureTracker
Differential Revision: http://reviews.llvm.org/D12814

llvm-svn: 247943
2015-09-17 21:10:06 +00:00
Matthias Braun d78ee54a54 MachineScheduler: Provide an option for node hiding cutoff and disable it by default
llvm-svn: 247942
2015-09-17 21:09:59 +00:00