Commit Graph

29 Commits

Author SHA1 Message Date
David Goodwin
557bbe6b5d Remove some old experimental code that is no longer needed. Remove additional, speculative scheduling pass as its cost did not translate into significant performance improvement. Minor tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89471 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-20 19:32:48 +00:00
David Goodwin
12dd99dc30 Rename registers to break output dependencies in addition to anti-dependencies.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@87015 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-12 19:08:21 +00:00
David Goodwin
4de099d8ca Do a scheduling pass ignoring anti-dependencies to identify candidate registers that should be renamed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85939 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-03 20:57:50 +00:00
Reid Kleckner
c277ab08a2 Fix integer overflow in instruction scheduling. This can happen if we have
basic blocks that are so long that their size overflows a short.

Also assert that overflow does not happen in the future, as requested by Evan.

This fixes PR4401.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83159 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-30 20:15:38 +00:00
Bill Wendling
960bb85b21 Convert DOUT to DEBUG(errs()...).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79760 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-22 20:41:06 +00:00
David Goodwin
c93d8373c9 Add some debug output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78687 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-11 17:35:23 +00:00
Daniel Dunbar
3f0e83067d Move to raw_ostream.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76963 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-24 09:53:24 +00:00
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
5cffa6fe27 Use iterators to iterate through the Preds array instead of
an index. This code is on the hot-path because the current
way SDep edges are uniqued has quadratic complexity.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64262 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-11 00:12:28 +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
f7119393a9 Instead of adding dependence edges between terminator instructions
and every other instruction in their blocks to keep the terminator
instructions at the end, teach the post-RA scheduler how to operate
on ranges of instructions, and exclude terminators from the range
of instructions that get scheduled.

Also, exclude mid-block labels, such as EH_LABEL instructions, and
schedule code before them separately from code after them. This
fixes problems with the post-RA scheduler moving code past
EH_LABELs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62366 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-16 22:10:20 +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
a1f50e2c2c Avoid referring to edge D after the Succs or Preds arrays have
been modified, to avoid trouble in the (unlikely) scenario that
D is a reference to an element in one of those arrays.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62173 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-13 19:08:45 +00:00
Dan Gohman
a80c859df3 Don't call setDepthDirty/setHeightDirty when adding an edge
with latency 0, since it doesn't affect the depth or height.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61762 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-05 22:40:26 +00:00
Dan Gohman
1578f8486d Minor code simplifications.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61371 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-23 17:22:32 +00:00
Dan Gohman
8044e9b3af Optimize setDepthDirty and setHeightDirty a little, as they showed
up on a profile.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61344 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-22 21:11:33 +00:00
Dan Gohman
e19c6362d2 Use SmallVector's pop_back_val.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61277 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-20 16:42:33 +00:00
Dan Gohman
f89e6e6577 Use the correct Preds and Succs lists in setHeightDirty()
and setDepthDirty(), respectively. This fixes PR3241.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61276 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-20 16:34:57 +00:00
Dan Gohman
fccf6dd377 Use getDepth() and getHeight() instead of accessing the
Depth and Height members directly, as they may not be
current.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61121 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-17 04:25:52 +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
c6b680eee5 Move addPred and removePred out-of-line.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61067 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 01:05:52 +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
e3a49cd944 Whitespace cleanups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60769 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-09 16:37:48 +00:00
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
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
40362067de Add #include <climits> to get the definition of INT_MAX.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59692 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-20 01:41:34 +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