Commit Graph

117 Commits

Author SHA1 Message Date
Dan Gohman
47ac0f0c7c When scheduling a block in parts, keep track of the overall
instruction index across each part. Instruction indices are used
to make live range queries, and live ranges can extend beyond
scheduling region boundaries.

Refactor the ScheduleDAGSDNodes class some more so that it
doesn't have to worry about this additional information.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64288 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-11 04:27:20 +00:00
Dan Gohman
9e64bbb322 Factor out more code for computing register live-range informationfor
scheduling, and generalize is so that preserves state across
scheduling regions. This fixes incorrect live-range information around
terminators and labels, which are effective region boundaries.

In place of looking for terminators to anchor inter-block dependencies,
introduce special entry and exit scheduling units for this purpose.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64254 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-10 23:27:53 +00:00
Dan Gohman
84fbac5809 Move ScheduleDAGSDNodes.h to be a private header. Front-ends
that previously included this header should include
SchedulerRegistry.h instead.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63937 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-06 17:22:58 +00:00
Dan Gohman
2836c283bb Initial hazard recognizer support in post-pass scheduling. This includes
a new toy hazard recognizier heuristic which attempts to direct the
scheduler to avoid clumping large groups of loads or stores too densely.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62291 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-16 01:33:36 +00:00
Dan Gohman
fc54c55296 Generalize the HazardRecognizer interface so that it can be used
to support MachineInstr-based scheduling in addition to
SDNode-based scheduling.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62284 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-15 22:18:12 +00:00
Dan Gohman
79ce276083 Move a few containers out of ScheduleDAGInstrs::BuildSchedGraph
and into the ScheduleDAGInstrs class, so that they don't get
destructed and re-constructed for each block. This fixes a
compile-time hot spot in the post-pass scheduler.

To help facilitate this, tidy and do some minor reorganization
in the scheduler constructor functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62275 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-15 19:20:50 +00:00
Dan Gohman
bc0b56732a The list-td and list-tdrr schedulers don't yet support physreg
scheduling dependencies. Add assertion checks to help catch
this.

It appears the Mips target defaults to list-td, and it has a
regression test that uses a physreg dependence. Such code was
liable to be miscompiled, and now evokes an assertion failure.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62177 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-13 20:24:13 +00:00
Dan Gohman
c9a5b9e38b Rename BuildSchedUnits to BuildSchedGraph, and refactor the
code in ScheduleDAGSDNodes' BuildSchedGraph into separate functions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61376 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-23 18:36:58 +00:00
Dan Gohman
3f23744df4 Fix some register-alias-related bugs in the post-RA scheduler liveness
computation code. Also, avoid adding output-depenency edges when both
defs are dead, which frequently happens with EFLAGS defs.

Compute Depth and Height lazily, and always in terms of edge latency
values. For the schedulers that don't care about latency, edge latencies
are set to 1.

Eliminate Cycle and CycleBound, and LatencyPriorityQueue's Latencies array.
These are all subsumed by the Depth and Height fields.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61073 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 03:25:46 +00:00
Dan Gohman
54e4c36a73 Rewrite the SDep class, and simplify some of the related code.
The Cost field is removed. It was only being used in a very limited way,
to indicate when the scheduler should attempt to protect a live register,
and it isn't really needed to do that. If we ever want the scheduler to
start inserting copies in non-prohibitive situations, we'll have to
rethink some things anyway.

A Latency field is added. Instead of giving each node a single
fixed latency, each edge can have its own latency. This will eventually
be used to model various micro-architecture properties more accurately.

The PointerIntPair class and an internal union are now used, which
reduce the overall size.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60806 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-09 22:54:47 +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
0454e8685f Update a comment to reflect the current code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59549 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-18 21:14:44 +00:00
Dan Gohman
6c2fe2237b Fix a typo in a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59489 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-18 02:50:01 +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
2dcca9d53e Use SUnit's CycleBound field instead of duplicating it in
a side-car datastructure


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59458 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-17 19:45:19 +00:00
Dan Gohman
6560c000a1 Don't use the isPending flag to mean what the isAvailable flag means.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59445 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-17 16:37:30 +00:00
Dan Gohman
14ad6fce43 Correct a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59341 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-15 00:24:23 +00:00
Dan Gohman
ade9f18934 Move ScheduleDAGList's LatencyPriorityQueue class out to a separate file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59340 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-15 00:23:40 +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
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
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
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
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
aabdded3b4 Use the new PriorityQueue in ScheduleDAGList too, which also
needs arbitrary-element removal.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52654 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-23 23:40:09 +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
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
80792f3dde Treat EntryToken nodes as "passive" so that they aren't added to the
ScheduleDAG; they don't correspond to any actual instructions so they
don't need to be scheduled.

This fixes a bug where the EntryToken was being scheduled multiple
times in some cases, though it ended up not causing any trouble because 
EntryToken doesn't expand into anything. With this fixed the schedulers
reliably schedule the expected number of units, so we can check this
with an assertion.

This requires a tweak to test/CodeGen/X86/loop-hoist.ll because it
ends up getting scheduled differently in a trivial way, though it was
enough to fool the prcontext+grep that the test does.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49701 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-15 01:22:18 +00:00
Dan Gohman
6f0d024a53 Rename MRegisterInfo to TargetRegisterInfo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46930 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-10 18:45:23 +00:00
Dan Gohman
3035959425 Use empty() instead of comparing size() with zero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46514 91177308-0d34-0410-b5e6-96231b3b80d8
2008-01-29 13:02:09 +00:00
Chris Lattner
84bc5427d6 Rename SSARegMap -> MachineRegisterInfo in keeping with the idea
that "machine" classes are used to represent the current state of
the code being compiled.  Given this expanded name, we can start 
moving other stuff into it.  For now, move the UsedPhysRegs and
LiveIn/LoveOuts vectors from MachineFunction into it.

Update all the clients to match.

This also reduces some needless #includes, such as MachineModuleInfo
from MachineFunction.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45467 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-31 04:13:23 +00:00
Chris Lattner
4ee451de36 Remove attribution from file headers, per discussion on llvmdev.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45418 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-29 20:36:04 +00:00
Evan Cheng
4859e277f7 Make CalcLatency() non-recursive.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43017 91177308-0d34-0410-b5e6-96231b3b80d8
2007-10-15 21:33:22 +00:00
Evan Cheng
74d2fd8dd8 Trim some unneeded fields.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42442 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-28 19:24:24 +00:00
Evan Cheng
a6fb1b6743 Added major new capabilities to scheduler (only BURR for now) to support physical register dependency. The BURR scheduler can now backtrace and duplicate instructions in order to avoid "expensive / impossible to copy" values (e.g. status flag EFLAGS for x86) from being clobbered.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42284 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-25 01:54:36 +00:00
Evan Cheng
713a98dee8 Use struct SDep instead of std::pair for SUnit pred and succ lists. First step
in tracking physical register output dependencies.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42125 91177308-0d34-0410-b5e6-96231b3b80d8
2007-09-19 01:38:40 +00:00
Dale Johannesen
e7e7d0d7e3 Skeleton of post-RA scheduler; doesn't do anything yet.
Change name of -sched option and DEBUG_TYPE to
pre-RA-sched; adjust testcases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39816 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-13 17:13:54 +00:00
Chris Lattner
2ba528b3a7 switch the sched unit map over to use a DenseMap instead of std::map. This
speeds up isel as a whole time by 2.6%.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33810 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-03 01:34:13 +00:00
Chris Lattner
cd3245ac45 Eliminate static ctors from Statistics
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32698 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-19 22:41:21 +00:00
Bill Wendling
832171cb97 Removing even more <iostream> includes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32320 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-07 20:04:42 +00:00
Chris Lattner
ac0b6ae358 Detemplatize the Statistic class. The only type it is instantiated with
is 'unsigned'.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32279 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-06 17:46:33 +00:00
Evan Cheng
95f6edeff5 Changes to use operand constraints to process two-address instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31453 91177308-0d34-0410-b5e6-96231b3b80d8
2006-11-04 09:44:31 +00:00