Commit Graph

135 Commits

Author SHA1 Message Date
Dan Gohman
21d9003087 Initial support for anti-dependence breaking. Currently this code does not
introduce any new spilling; it just uses unused registers.

Refactor the SUnit topological sort code out of the RRList scheduler and
make use of it to help with the post-pass scheduler.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59999 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-25 00:52:40 +00:00
Dan Gohman
942b8c8533 Check in the rest of this change. The isAntiDep flag needs to be passed
to removePred because an SUnit can both data-depend and anti-depend
on the same SUnit.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59969 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-24 17:33:52 +00:00
Dan Gohman
cddd428459 Add a flag to SDep for tracking which edges are anti-dependence edges.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59785 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-21 02:27:52 +00:00
Dan Gohman
98adea1149 Rename SDep's isSpecial to isArtificial, to make this field a little
less mysterious.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59782 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-21 02:18:56 +00:00
Dan Gohman
f209c2cc30 Remove the CycleBound computation code from the ScheduleDAGRRList
schedulers. This doesn't have much immediate impact because
targets that use these schedulers by default don't yet provide
pipeline information.

This code also didn't have the benefit of register pressure
information. Also, removing it will avoid problems with list-burr
suddenly starting to do latency-oriented scheduling on x86 when we
start providing pipeline data, which would increase spilling.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59775 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-21 01:30:54 +00:00
Dan Gohman
47d1a214a7 Change these schedulers to not emit no-ops. It turns out that
the RR scheduler actually does look at latency values, but it
doesn't use a hazard recognizer so it has no way to know when
a no-op is needed, as opposed to just stalling and incrementing
the cycle count.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59759 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-21 00:10:42 +00:00
Dan Gohman
57bebbbd12 Remove a remnant of list-burr's fast mode.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59702 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-20 03:32:45 +00:00
Dan Gohman
117f3e9ee4 Factor out the SethiUllman numbering logic from the list-burr and
list-tdrr schedulers into a common base class.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59701 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-20 03:30:37 +00:00
Dan Gohman
9e76fea3ab Remove the "fast" form of the list-burr scheduler, and use the
dedicated "fast" scheduler in -fast mode instead, which is
faster. This speeds up llc -fast by a few percent on some
testcases -- the speedup only happens for code not handled by
fast-isel.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59700 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-20 03:11:19 +00:00
Dan Gohman
6be2ee431f Facter AddPseudoTwoAddrDeps and associated infrasructure out of
the list-burr scheduler so that it can be used by the list-tdrr
scheduler too.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59698 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-20 02:45:51 +00:00
Dan Gohman
a1e6d363e5 Factor out the code for verifying the work of the scheduler,
extend it a bit, and make use of it in all schedulers, to
ensure consistent checking.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59689 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-20 01:26:25 +00:00
Dan Gohman
343f0c0467 Experimental post-pass scheduling support. Post-pass scheduling
is currently off by default, and can be enabled with
-disable-post-RA-scheduler=false.

This doesn't have a significant impact on most code yet because it doesn't
yet do anything to address anti-dependencies and it doesn't attempt to
disambiguate memory references. Also, several popular targets
don't have pipeline descriptions yet.

The majority of the changes here are splitting the SelectionDAG-specific
code out of ScheduleDAG, so that ScheduleDAG can be moved to
libLLVMCodeGen.a. The interface between ScheduleDAG-using code and
the rest of the scheduling code is somewhat rough and will evolve.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59676 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-19 23:18:57 +00:00
Dan Gohman
c2f9062ea4 Rearrange code to reduce the nesting level. No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59580 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-19 02:00:32 +00:00
Dan Gohman
1256f5fe76 Tidy up ScheduleNodeBottomUp methods, and make them more
consistent with ScheduleNodeTopDown methods.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59550 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-18 21:22:20 +00:00
Dan Gohman
3cc6243ddf Change SUnit's dump method to take a ScheduleDAG* instead of
a SelectionDAG*.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59488 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-18 02:06:40 +00:00
Dan Gohman
2d093f3560 Avoid using a loop in ReleasePred and ReleaseSucc methods to compute the
new CycleBound value. Instead, just update CycleBound on each call.
Also, make ReleasePred and ReleaseSucc methods more consistent accross
the various schedulers.

This also happens to make ScheduleDAGRRList's CycleBound computation
somewhat more interesting, though it still doesn't have any noticeable
effect, because no current targets that use the register-pressure
reduction scheduler provide pipeline models.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59475 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-18 00:38:59 +00:00
Dan Gohman
8123419f2b Eliminate some trivial differences between the ScheduleNodeTopDown
functions in these two schedulers.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59465 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-17 21:31:02 +00:00
Dan Gohman
d23e0f81bc Remove the FlaggedNodes member from SUnit. Instead of requiring each SUnit
to carry a SmallVector of flagged nodes, just calculate the flagged nodes
dynamically when they are needed.

The local-liveness change is due to a trivial scheduling change where
the scheduler arbitrary decision differently.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59273 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-13 23:24:17 +00:00
Dan Gohman
550f5afb68 Make the Node member of SUnit private, and add accessors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59264 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-13 21:36:12 +00:00
Dan Gohman
a23b3b803e Change ScheduleDAG's DAG member from a reference to a pointer, to prepare
for the possibility of scheduling without a SelectionDAG being present.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59263 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-13 21:21:28 +00:00
Dan Gohman
b13af2f2ec In ScheduleDAGRRList::CopyAndMoveSuccessors, create the SUnit for the load
before creating the SUnit for the operation that it was unfolded from. This
allows each SUnit to have all of its predecessor SUnits available at the time
it is created. I don't know yet if this will be absolutely required, but it
is a little tidier to do it this way.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59083 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-11 21:34:44 +00:00
Dan Gohman
9b75b37375 Change the scheduler accessor methods to accept an explicit TargetMachine
argument instead of taking the SelectionDAG's TargetMachine. This is
needed for some upcoming scheduler changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59055 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-11 17:50:47 +00:00
Dan Gohman
87e82f00ad Remove some unused virtual function bodies.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@58524 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-31 19:06:33 +00:00
Dan Gohman
b8cab9227a Fix command-line option printing to print two spaces where needed,
instead of requiring all "short description" strings to begin with
two spaces. This makes these strings less mysterious, and it fixes
some cases where short description strings mistakenly did not
begin with two spaces.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57521 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-14 20:25:08 +00:00
Dan Gohman
086ec9976f Replace the LiveRegs SmallSet with a simple counter that keeps
track of the number of live registers, which is all the set was
being used for.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56498 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-23 18:50:48 +00:00
Dan Gohman
59932584a8 Don't worry about clobbering physical register defs that aren't used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56281 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-17 15:25:49 +00:00
Gabor Greif
ba36cb5242 erect abstraction boundaries for accessing SDValue members, rename Val -> Node to reflect semantics
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55504 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-28 21:40:38 +00:00
Dan Gohman
e5a8dc5cc4 Optimize ScheduleDAGRRList's topological sort to use one pass instead
of two, and to not need a scratch std::vector. Also, compute the ordering
immediately in the result array, instead of in another scratch std::vector
that is copied to the result array.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55421 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-27 16:29:48 +00:00
Gabor Greif
99a6cb92d1 disallow direct access to SDValue::ResNo, provide a getter instead
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@55394 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-26 22:36:50 +00:00
Dan Gohman
04f4f4f447 Correct the filename in the top-of-file comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54688 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-12 17:42:33 +00:00
Dan Gohman
430b8a22e2 Fix several const-correctness issues, resolving some -Wcast-qual warnings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54349 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-05 14:45:15 +00:00
Dan Gohman
475871a144 Rename SDOperand to SDValue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54128 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-27 21:46:04 +00:00
Dan Gohman
e8be6c6391 Add a new function, ReplaceAllUsesOfValuesWith, which handles bulk
replacement of multiple values. This is slightly more efficient
than doing multiple ReplaceAllUsesOfValueWith calls, and theoretically
could be optimized even further. However, an important property of this
new function is that it handles the case where the source value set and
destination value set overlap. This makes it feasible for isel to use
SelectNodeTo in many very common cases, which is advantageous because
SelectNodeTo avoids a temporary node and it doesn't require CSEMap
updates for users of values that don't change position.

Revamp MorphNodeTo, which is what does all the work of SelectNodeTo, to
handle operand lists more efficiently, and to correctly handle a number
of corner cases to which its new wider use exposes it.

This commit also includes a change to the encoding of post-isel opcodes
in SDNodes; now instead of being sandwiched between the target-independent
pre-isel opcodes and the target-dependent pre-isel opcodes, post-isel
opcodes are now represented as negative values. This makes it possible
to test if an opcode is pre-isel or post-isel without having to know
the size of the current target's post-isel instruction set.

These changes speed up llc overall by 3% and reduce memory usage by 10%
on the InstructionCombining.cpp testcase with -fast and -regalloc=local.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53728 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-17 19:10:17 +00:00
Dan Gohman
5e84368b26 Reapply 53476 and 53480, with a fix so that it properly updates
the BB member to the current basic block after emitting
instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53567 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-14 18:19:29 +00:00
Evan Cheng
b5eec33dcd Back out 53476 and 53480 for now. Somehow they cause llc to miscompile 179.art.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53502 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-12 01:38:51 +00:00
Dan Gohman
0f4012f475 Factor out debugging code into the common base class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53480 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-11 22:36:22 +00:00
Dan Gohman
dbe2a5a269 Add support for putting NamedRegionTimers in TimerGroups, and
use a timer group for the timers in SelectionDAGISel. Also,
Split scheduling out from emitting, to give each their own
timer.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53476 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-11 21:54:34 +00:00
Evan Cheng
c6be777208 - Use a faster priority comparison function if -fast.
- Code clean up.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53010 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-02 09:23:51 +00:00
Evan Cheng
4576f6d7a9 Do not use computationally expensive scheduling heuristics with -fast.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52971 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-01 18:05:03 +00:00
Dan Gohman
8cb8245cf1 Move a DenseMap's declaration outside of a loop, and just call
clear() on each iteration. This avoids allocating and deallocating
all of DenseMap's memory on each iteration.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52642 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-23 21:15:00 +00:00
Dan Gohman
2f1d3108e4 canClobberPhysRegDefs shouldn't called without checking hasPhysRegDefs;
check this with an assert.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52603 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-21 22:05:24 +00:00
Dan Gohman
94d7a5f815 Remove ScheduleDAG's SUnitMap altogether. Instead, use SDNode's NodeId
field, which is otherwise unused after instruction selection, as an index
into the SUnit array.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52583 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-21 19:18:17 +00:00
Dan Gohman
3627e34486 Add a priority queue class, which is a wrapper around std::priority_queue
and provides fairly efficient removal of arbitrary elements. Switch
ScheduleDAGRRList from std::set to this new priority queue.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52582 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-21 18:35:25 +00:00
Dan Gohman
4c8c83022b Change ScheduleDAG's SUnitMap from DenseMap<SDNode*, vector<SUnit*> >
to DenseMap<SDNode*, SUnit*>, and adjust the way cloned SUnit nodes are
handled so that only the original node needs to be in the map.
This speeds up llc on 447.dealII.llvm.bc by about 2%.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52576 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-21 15:52:51 +00:00
Dan Gohman
16c6859651 Simplify some template parameterization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52571 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-21 01:08:22 +00:00
Duncan Sands
83ec4b6711 Wrap MVT::ValueType in a struct to get type safety
and better control the abstraction.  Rename the type
to MVT.  To update out-of-tree patches, the main
thing to do is to rename MVT::ValueType to MVT, and
rewrite expressions like MVT::getSizeInBits(VT) in
the form VT.getSizeInBits().  Use VT.getSimpleVT()
to extract a MVT::SimpleValueType for use in switch
statements (you will get an assert failure if VT is
an extended value type - these shouldn't exist after
type legalization).
This results in a small speedup of codegen and no
new testsuite failures (x86-64 linux).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52044 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-06 12:08:01 +00:00
Duncan Sands
419cafb9fb Silence the compiler warning differently. The
original method caused gcc-4.2 to complain.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51186 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-16 09:19:16 +00:00
Evan Cheng
5087124721 Silence some compiler warnings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51115 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-14 20:07:51 +00:00
Roman Levenstein
a0201d5204 Use std::set instead of std::priority_queue for the RegReductionPriorityQueue.
This removes the existing bottleneck related to the removal of elements from 
the middle of the queue.

Also fixes a subtle bug in ScheduleDAGRRList::CapturePred:
It was updating the state of the SUnit before removing it. As a result, the
comparison operators were working incorrectly and this SUnit could not be removed 
from the queue properly.

Reviewed by Evan and Dan. Approved by Dan.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50412 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-29 09:07:59 +00:00
Dan Gohman
5a2d335c4c Fix the new scheduler assertion checks to work when
the scheduler has inserted no-ops. This fixes
the 2006-07-03-schedulers.ll regression on ppc32.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49747 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-15 22:40:14 +00:00