Commit Graph

247 Commits

Author SHA1 Message Date
Matthias Braun a04d7ad851 RegisterCoalescer: Simplify subrange splitting code; NFC
- Use slightly better variable names / compute in a more direct way.

llvm-svn: 296905
2017-03-03 19:05:34 +00:00
Matthias Braun 8c209aa877 Cleanup dump() functions.
We had various variants of defining dump() functions in LLVM. Normalize
them (this should just consistently implement the things discussed in
http://lists.llvm.org/pipermail/cfe-dev/2014-January/034323.html

For reference:
- Public headers should just declare the dump() method but not use
  LLVM_DUMP_METHOD or #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
- The definition of a dump method should look like this:
  #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
  LLVM_DUMP_METHOD void MyClass::dump() {
    // print stuff to dbgs()...
  }
  #endif

llvm-svn: 293359
2017-01-28 02:02:38 +00:00
Krzysztof Parzyszek ea9f8ce03c Implement LaneBitmask::any(), use it to replace !none(), NFCI
llvm-svn: 289974
2016-12-16 19:11:56 +00:00
Krzysztof Parzyszek 91b5cf8412 Extract LaneBitmask into a separate type
Specifically avoid implicit conversions from/to integral types to
avoid potential errors when changing the underlying type. For example,
a typical initialization of a "full" mask was "LaneMask = ~0u", which
would result in a value of 0x00000000FFFFFFFF if the type was extended
to uint64_t.

Differential Revision: https://reviews.llvm.org/D27454

llvm-svn: 289820
2016-12-15 14:36:06 +00:00
Krzysztof Parzyszek a7ed090bba Create subranges for new intervals resulting from live interval splitting
The register allocator can split a live interval of a register into a set
of smaller intervals. After the allocation of registers is complete, the
rewriter will modify the IR to replace virtual registers with the corres-
ponding physical registers. At this stage, if a register corresponding
to a subregister of a virtual register is used, the rewriter will check
if that subregister is undefined, and if so, it will add the <undef> flag
to the machine operand. The function verifying liveness of the subregis-
ter would assume that it is undefined, unless any of the subranges of the
live interval proves otherwise.
The problem is that the live intervals created during splitting do not
have any subranges, even if the original parent interval did. This could
result in the <undef> flag placed on a register that is actually defined.

Differential Revision: http://reviews.llvm.org/D21189

llvm-svn: 279625
2016-08-24 13:37:55 +00:00
David Majnemer c700490f48 Use the range variant of remove_if instead of unpacking begin/end
No functionality change is intended.

llvm-svn: 278475
2016-08-12 04:32:37 +00:00
Krzysztof Parzyszek f5b9bb61f7 Add print/dump routines to LiveInterval::SubRange
llvm-svn: 275194
2016-07-12 17:37:44 +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 71f9564e7f LiveIntervalAnalysis: Rework constructMainRangeFromSubranges()
We now use LiveRangeCalc::extendToUses() instead of a specially designed
algorithm in constructMainRangeFromSubranges():
- The original motivation for constructMainRangeFromSubranges() were
  differences between the main liverange and subranges because of hidden
  dead definitions. This case however cannot happen anymore with the
  DetectDeadLaneMasks pass in place.
- It simplifies the code.
- This fixes a longstanding bug where we did not properly create new SSA
  values on merging control flow (the MachineVerifier missed most of
  these cases).
- Move constructMainRangeFromSubranges() to LiveIntervalAnalysis and
  LiveRangeCalc to better match the implementation/available helper
  functions.

This re-applies r269016. The fixes from r270290 and r270259 should avoid
the machine verifier problems this time.

llvm-svn: 270291
2016-05-20 23:14:56 +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
Tom Stellard 740af6f3b0 Revert "LiveIntervalAnalysis: Rework constructMainRangeFromSubranges()"
This reverts commit r269016 and also the follow-up commit r269020.

This patch caused PR27705.

llvm-svn: 269344
2016-05-12 20:27:40 +00:00
Matthias Braun 8d6e57b216 LiveIntervalAnalysis: Rework constructMainRangeFromSubranges()
We now use LiveRangeCalc::extendToUses() instead of a specially designed
algorithm in constructMainRangeFromSubranges():
- The original motivation for constructMainRangeFromSubranges() were
  differences between the main liverange and subranges because of hidden
  dead definitions. This case however cannot happen anymore with the
  DetectDeadLaneMasks pass in place.
- It simplifies the code.
- This fixes a longstanding bug where we did not properly create new SSA
  values on merging control flow (the MachineVerifier missed most of
  these cases).
- Move constructMainRangeFromSubranges() to LiveIntervalAnalysis and
  LiveRangeCalc to better match the implementation/available helper
  functions.

llvm-svn: 269016
2016-05-10 04:51:14 +00:00
Matthias Braun 9c7e4dea1f LiveInterval: Avoid unnecessary auto, add const; NFC
llvm-svn: 269015
2016-05-10 04:51:09 +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
Matthias Braun ae81c29352 LiveInterval: Fix Distribute() failing on liveranges with unused VNInfos
This fixes http://llvm.org/PR26991

llvm-svn: 264345
2016-03-24 21:41:38 +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
Richard Trieu 7a08381403 Remove uses of builtin comma operator.
Cleanup for upcoming Clang warning -Wcomma.  No functionality change intended.

llvm-svn: 261270
2016-02-18 22:09:30 +00:00
Andrew Kaylor 1224488e0c [regalloc][WinEH] Do not mark intervals as not spillable if they contain a regmask
Differential Revision: http://reviews.llvm.org/D16831

llvm-svn: 260164
2016-02-08 22:52:51 +00:00
Yaron Keren eb2a25467e Annotate dump() methods with LLVM_DUMP_METHOD, addressing Richard Smith r259192 post commit comment.
clang part in r259232, this is the LLVM part of the patch.

llvm-svn: 259240
2016-01-29 20:50:44 +00:00
Matthias Braun 3907fded1b LiveInterval: Add utility class to rename independent subregister usage
This renaming is necessary to avoid a subregister aware scheduler
accidentally creating liveness "holes" which are rejected by the
MachineVerifier.

Explanation as found in this patch:

Helper class that can divide MachineOperands of a virtual register into
equivalence classes of connected components.
MachineOperands belong to the same equivalence class when they are part of
the same SubRange segment or adjacent segments (adjacent in control
flow); Different subranges affected by the same MachineOperand belong to
the same equivalence class.

Example:
  vreg0:sub0 = ...
  vreg0:sub1 = ...
  vreg0:sub2 = ...
  ...
  xxx        = op vreg0:sub1
  vreg0:sub1 = ...
  store vreg0:sub0_sub1

The example contains 3 different equivalence classes:
  - One for the (dead) vreg0:sub2 definition
  - One containing the first vreg0:sub1 definition and its use,
    but not the second definition!
  - The remaining class contains all other operands involving vreg0.

We provide a utility function here to rename disjunct classes to different
virtual registers.

Differential Revision: http://reviews.llvm.org/D16126

llvm-svn: 258257
2016-01-20 00:23:21 +00:00
Matthias Braun bf47f63b74 LiveInterval: A LiveRange is enough for ConnectedVNInfoEqClasses::Classify()
llvm-svn: 257129
2016-01-08 01:16:35 +00:00
Matthias Braun c804cdb912 TargetRegisterInfo: Introduce PrintLaneMask.
This makes it more convenient to print lane masks and lead to more
uniform printing.

llvm-svn: 248624
2015-09-25 21:51:24 +00:00
Matthias Braun e6a2485e1a TargetRegisterInfo: Add typedef unsigned LaneBitmask and use it where apropriate; NFC
llvm-svn: 248623
2015-09-25 21:51:14 +00:00
Matt Arsenault 50f0a42b66 Fix typo
llvm-svn: 248549
2015-09-24 22:36:49 +00:00
Matthias Braun 5efe871971 LiveInterval: Distribute subregister liveranges to new intervals in ConnectedVNInfoEqClasses::Distribute()
This improves ConnectedVNInfoEqClasses::Distribute() to distribute the
segments and value numbers in the subranges instead of conservatively
clearing all subregister info.

No separate test here, just clearing the subrange instead of properly
distributing them would however break my upcoming fix regarding dead super
register definitions.

Differential Revision: http://reviews.llvm.org/D13075

llvm-svn: 248334
2015-09-22 22:37:42 +00:00
Matthias Braun d3dd1354a4 LiveIntervalAnalysis: Factor common code into splitSeparateComponents; NFC
llvm-svn: 248241
2015-09-22 03:44:41 +00:00
Matthias Braun 0d4cebd434 LiveInterval: Document and enforce rules about empty subranges.
Empty subranges are not allowed in a LiveInterval and must be removed
instead: Check this in the verifiers, put a reminder for this in the
comment of the shrinkToUses variant for a single lane and make it
automatic for the shrinkToUses variant for a LiveInterval.

llvm-svn: 242431
2015-07-16 18:55:35 +00:00
Matthias Braun 9b9210264f Oops, didn't mean to commit my debug fprintfs
llvm-svn: 234385
2015-04-08 02:10:01 +00:00
Matthias Braun 1e61bbf022 LiveInterval: Fix computeFromMainRange() producing adjacent segments with same valno
If two livesegments from different subranges happened to have the same
definition they could possibly end up as two adjacent segments in the
main liverange with the same value number which is not allowed. Detect
such cases and fix them in the 2nd pass of computeFromMainRange() if
necessary.

No testcase as there is only an out-of-tree target where I can sensibly
come up with one.

llvm-svn: 234382
2015-04-08 01:41:10 +00:00
Benjamin Kramer 51f6096cf8 Move private classes into anonymous namespaces
NFC.

llvm-svn: 232944
2015-03-23 12:30:58 +00:00
David Blaikie ed40025f37 Recommit r231168: unique_ptrify LiveRange::segmentSet
GCC 4.7's libstdc++ doesn't have std::map::emplace, but it does have
std::unordered_map::emplace, and the use case here doesn't appear to
need ordering. The container has been changed in a separate/precursor
patch, and now this patch should hopefully build cleanly even with
GCC 4.7.

& then I realized the order of the container did matter, so extra
handling of ordering was added in r231189.

Original commit message:
This makes LiveRange non-copyable, and LiveInterval is already
non-movable (due to the explicit dtor), so now it's non-copyable and
non-movable.

Fix the one case where we were relying on the (deprecated in C++11)
implicit copy ctor of LiveInterval (which happened to work because the
ctor created an object with a null segmentSet, so double-deleting the
null pointer was fine).

llvm-svn: 231192
2015-03-04 01:20:33 +00:00
David Blaikie 90c59ccae6 Revert "unique_ptrify LiveRange::segmentSet"
Apparently something does care about ordering of LiveIntervals... so
revert all that stuff (r231175, r231176, r231177) & take some time to
re-evaluate.

llvm-svn: 231184
2015-03-04 00:15:02 +00:00
David Blaikie 19660f03be Recommit r231168: unique_ptrify LiveRange::segmentSet
GCC 4.7's libstdc++ doesn't have std::map::emplace, but it does have
std::unordered_map::emplace, and the use case here doesn't appear to
need ordering. The container has been changed in a separate/precursor
patch, and now this patch should hopefully build cleanly even with
GCC 4.7.

Original commit message:
This makes LiveRange non-copyable, and LiveInterval is already
non-movable (due to the explicit dtor), so now it's non-copyable and
non-movable.

Fix the one case where we were relying on the (deprecated in C++11)
implicit copy ctor of LiveInterval (which happened to work because the
ctor created an object with a null segmentSet, so double-deleting the
null pointer was fine).

llvm-svn: 231176
2015-03-03 23:53:03 +00:00
David Blaikie 923a25e957 Revert "unique_ptrify LiveRange::segmentSet"
GCC 4.7 *shakes fist* (doesn't have std::map::emplace... )

This reverts commit r231168.

llvm-svn: 231173
2015-03-03 23:44:07 +00:00
David Blaikie 5a0206a3ff unique_ptrify LiveRange::segmentSet
This makes LiveRange non-copyable, and LiveInterval is already
non-movable (due to the explicit dtor), so now it's non-copyable and
non-movable.

Fix the one case where we were relying on the (deprecated in C++11)
implicit copy ctor of LiveInterval (which happened to work because the
ctor created an object with a null segmentSet, so double-deleting the
null pointer was fine).

llvm-svn: 231168
2015-03-03 23:30:40 +00:00
David Blaikie 7f1e0565b3 Revert "Remove the explicit SDNodeIterator::operator= in favor of the implicit default"
Accidentally committed a few more of these cleanup changes than
intended. Still breaking these out & tidying them up.

This reverts commit r231135.

llvm-svn: 231136
2015-03-03 21:18:16 +00:00
David Blaikie bb8da4c08f Remove the explicit SDNodeIterator::operator= in favor of the implicit default
There doesn't seem to be any need to assert that iterator assignment is
between iterators over the same node - if you want to reuse an iterator
variable to iterate another node, that's perfectly acceptable. Just
don't mix comparisons between iterators into disjoint sequences, as
usual.

llvm-svn: 231135
2015-03-03 21:17:08 +00:00
Benjamin Kramer 4c5dcb0a83 LiveRange: Replace a creative vector erase loop with std::remove_if.
I didn't see this so far because it scans backwards, but that doesn't
make it any less quadratic. NFC.

llvm-svn: 230863
2015-02-28 20:14:27 +00:00
Matthias Braun 11042c8523 LiveRangeCalc: Rename some parameters from kill to use, NFC.
Those parameters did not necessarily describe kill points but just uses.

llvm-svn: 229601
2015-02-18 01:50:52 +00:00
Quentin Colombet a8cb36ea43 [LiveIntervalAnalysis] Speed up creation of live ranges for physical registers
by using a segment set.

The patch addresses a compile-time performance regression in the LiveIntervals
analysis pass (see http://llvm.org/bugs/show_bug.cgi?id=18580). This regression
is especially critical when compiling long functions. Our analysis had shown
that the most of time is taken for generation of live intervals for physical
registers. Insertions in the middle of the array of live ranges cause quadratic
algorithmic complexity, which is apparently the main reason for the slow-down. 

Overview of changes:
- The patch introduces an additional std::set<Segment>* member in LiveRange for
  storing segments in the phase of initial creation. The set is used if this
  member is not NULL, otherwise everything works the old way. 
- The set of operations on LiveRange used during initial creation (i.e. used by
  createDeadDefs and extendToUses) have been reimplemented to use the segment
  set if it is available.
- After a live range is created the contents of the set are flushed to the
  segment vector, because the set is not as efficient as the vector for the
  later uses of the live range. After the flushing, the set is deleted and
  cannot be used again.
- The set is only for live ranges computed in
  LiveIntervalAnalysis::computeLiveInRegUnits() and getRegUnit() but not in
  computeVirtRegs(), because I did not bring any performance benefits to
  computeVirtRegs() and for some examples even brought a slow down.

Patch by Vaidas Gasiunas <vaidas.gasiunas@sap.com>

Differential Revision: http://reviews.llvm.org/D6013

llvm-svn: 228421
2015-02-06 18:42:41 +00:00
Matthias Braun 7dc96dea0a LiveInterval: Fix SubRange memory leak.
llvm-svn: 228405
2015-02-06 17:28:47 +00:00
Matthias Braun 4fe686af00 LiveInterval: Implement feedback by Quentin Colombet.
llvm-svn: 225413
2015-01-07 23:35:11 +00:00
Matthias Braun 51ca510094 LiveInterval: Remove accidentally committed debug code.
llvm-svn: 224807
2014-12-24 02:35:07 +00:00
Matthias Braun dbcca0dbb4 LiveInterval: Introduce createMainRangeFromSubranges().
This function constructs the main liverange by merging all subranges if
subregister liveness tracking is available. This should be slightly
faster to compute instead of performing the liveness calculation again
for the main range. More importantly it avoids cases where the main
liverange would cover positions where no subrange was live. These cases
happened for partial definitions where the actual defined part was dead
and only the undefined parts used later.

The register coalescing requires that every part covered by the main
live range has at least one subrange live.

I also expect this function to become usefull later for places where the
subranges are modified in a way that it is hard to correctly fix the
main liverange in the machine scheduler, we can simply reconstruct it
from subranges then.

llvm-svn: 224806
2014-12-24 02:11:51 +00:00
Matthias Braun 09afa1ea74 LiveInterval: Use range based for loops for subregister ranges.
llvm-svn: 223991
2014-12-11 00:59:06 +00:00
Matthias Braun 96761959d4 LiveInterval: Use more range based for loops for value numbers and segments.
llvm-svn: 223978
2014-12-10 23:07:54 +00:00
Matthias Braun 2079aa9140 LiveInterval: Add removeEmptySubRanges().
llvm-svn: 223887
2014-12-10 01:12:40 +00:00
Matthias Braun 3f1d8fdd33 LiveInterval: Add support to track liveness of subregisters.
This code adds the required data structures. Algorithms to compute it follow.

llvm-svn: 223877
2014-12-10 01:12:10 +00:00
Matthias Braun e62c207092 LiveInterval: Add a 'covers' operation to LiveRange.
llvm-svn: 223876
2014-12-10 01:12:06 +00:00
David Blaikie 70573dcd9f Update SetVector to rely on the underlying set's insert to return a pair<iterator, bool>
This is to be consistent with StringSet and ultimately with the standard
library's associative container insert function.

This lead to updating SmallSet::insert to return pair<iterator, bool>,
and then to update SmallPtrSet::insert to return pair<iterator, bool>,
and then to update all the existing users of those functions...

llvm-svn: 222334
2014-11-19 07:49:26 +00:00