Commit Graph

124 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen
fff2c4726b Also recompute HasPHIKill flags in LiveInterval::RenumberValues.
If a phi-def value were removed from the interval, the phi-kill flags are no
longer valid.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110949 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-12 20:38:03 +00:00
Jakob Stoklund Olesen
1b2932024f Remove trailing whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110944 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-12 20:01:23 +00:00
Jakob Stoklund Olesen
df30cf9e61 Transpose the calculation of spill weights such that we are calculating one
register at a time. This turns out to be slightly faster than iterating over
instructions, but more importantly, it allows us to compute spill weights for
new registers created after the spill weight pass has run.

Also compute the allocation hint at the same time as the spill weight. This
allows us to use the spill weight as a cost metric for copies, and choose the
most profitable hint if there is more than one possibility.

The new hints provide a very small (< 0.1%) but universal code size improvement.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110631 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-10 00:02:26 +00:00
Jakob Stoklund Olesen
23436597a8 Add LiveInterval::RenumberValues - Garbage collection for VNInfos.
After heavy editing of a live interval, it is much easier to simply renumber the
live values instead of trying to keep track of the unused ones.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110463 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-06 18:46:59 +00:00
Oscar Fuentes
ee56c42168 Prefix next' iterator operation with llvm::'.
Fixes potential ambiguity problems on VS 2010.

Patch by nobled!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110029 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-02 06:00:15 +00:00
Lang Hames
6f4e4df100 Factored out a bit of common code to mark VNInfos for deletion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109388 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-26 01:49:41 +00:00
Jakob Stoklund Olesen
d9f6ec977a Print VNInfo flags.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108277 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-13 21:19:05 +00:00
Jakob Stoklund Olesen
6382d2cadd Add an assertion to make PR7542 fail consistently.
LiveInterval::overlapsFrom dereferences end() if it is called on an empty
interval.

It would be reasonable to just return false - an empty interval doesn't overlap
anything, but I want to know who is doing it first.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108264 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-13 19:56:28 +00:00
Jakob Stoklund Olesen
186eb73845 Fix LiveInterval::overlaps so it doesn't claim touching intervals overlap.
Also, one binary search is enough.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108261 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-13 19:42:20 +00:00
Duncan Sands
90c64f4aac Remove initialized but otherwise unused variables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107127 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-29 11:22:26 +00:00
Jakob Stoklund Olesen
15a571436d Don't track kills in VNInfo. Use interval ends instead.
The VNInfo.kills vector was almost unused except for all the code keeping it
updated. The few places using it were easily rewritten to check for interval
ends instead.

The two new methods LiveInterval::killedAt and killedInRange are replacements.

This brings us down to 3 independent data structures tracking kills.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106905 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-25 22:53:05 +00:00
Jakob Stoklund Olesen
fa1e73c447 Make sure all eliminated kills are removed from VNInfo lists.
This fixes PR7479 and PR7485. The test cases from those PRs are big, so not
included. However, PR7485 comes from self hosting on FreeBSD, so we will surely
hear about any regression.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106811 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24 23:57:35 +00:00
Jakob Stoklund Olesen
014b8631c0 Add a few VNInfo data structure checks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106627 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-23 15:34:36 +00:00
Benjamin Kramer
991de14dd6 Introduce SpecificBumpPtrAllocator, a wrapper for BumpPtrAllocator which allows
only a single type of object to be allocated. Use it to make VNInfo destruction
typesafe.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99919 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-30 20:16:45 +00:00
Daniel Dunbar
7a8cf2822d Fix -Asserts warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99895 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-30 17:57:42 +00:00
Torok Edwin
01cb1b665d Reapply r99881 with some fixes: only call destructor in releaseMemory!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99883 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-30 11:17:48 +00:00
Bob Wilson
86af655521 Fix a comment typo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93261 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-12 22:18:56 +00:00
David Greene
5242154b55 Change errs() to dbgs().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92528 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-04 22:41:43 +00:00
Lang Hames
6194569d22 Added a new "splitting" spiller.
When a call is placed to spill an interval this spiller will first try to
break the interval up into its component values. Single value intervals and
intervals which have already been split (or are the result of previous splits)
are spilled by the default spiller.

Splitting intervals as described above may improve the performance of generated
code in some circumstances. This work is experimental however, and it still
miscompiles many benchmarks. It's not recommended for general use yet.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90951 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-09 05:39:12 +00:00
Lang Hames
233a60ec40 The Indexes Patch.
This introduces a new pass, SlotIndexes, which is responsible for numbering
instructions for register allocation (and other clients). SlotIndexes numbering
is designed to match the existing scheme, so this patch should not cause any
changes in the generated code.

For consistency, and to avoid naming confusion, LiveIndex has been renamed
SlotIndex.

The processImplicitDefs method of the LiveIntervals analysis has been moved
into its own pass so that it can be run prior to SlotIndexes. This was
necessary to match the existing numbering scheme.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85979 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-03 23:52:08 +00:00
Lang Hames
6cc91e39c0 Oops. Renamed remaining MachineInstrIndex references.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83255 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-03 04:31:31 +00:00
Lang Hames
cc3b0650f1 Renamed MachineInstrIndex to LiveIndex.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83254 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-03 04:21:37 +00:00
Lang Hames
35f291d2c5 Moved some more index operations over to LiveIntervals.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81605 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-12 03:34:03 +00:00
Lang Hames
8651125d28 Replaces uses of unsigned for indexes in LiveInterval and VNInfo with
a new class, MachineInstrIndex, which hides arithmetic details from
most clients. This is a step towards allowing the register allocator
to update/insert code during allocation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81040 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-04 20:41:11 +00:00
Chris Lattner
c02497f5ba shoot a few more std::ostream print methods in the head.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79814 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23 03:47:42 +00:00
Lang Hames
52c1afcaea Modified VNInfo. The "copy" member is now a union which holds the copy for a register interval, or the defining register for a stack interval. Access is via getCopy/setCopy and getReg/setReg.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78620 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-10 23:43:28 +00:00
Daniel Dunbar
a717b7be88 More move to raw_ostream.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76966 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-24 10:47:20 +00:00
Daniel Dunbar
1cd1d98232 Move more to raw_ostream, provide support for writing MachineBasicBlock,
LiveInterval, etc to raw_ostream.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76965 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-24 10:36:58 +00:00
David Greene
92b78bbc7f Reorder if-else branches as suggested by Bill.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76808 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-22 22:32:19 +00:00
David Greene
29ff37f39c Make some changes suggested by Bill and Evan.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76775 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-22 20:08:25 +00:00
David Greene
80607c9b2b Add some support for iterative coalescers to calculate a joined live
range's weight properly.  This is turned off right now in the sense that
you'll get an assert if you get into a situation that can only be caused
by an iterative coalescer.  All other code paths operate exactly as
before so there is no functional change with this patch.  The asserts
should be disabled if/when an iterative coalescer gets added to trunk.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76680 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-21 23:36:14 +00:00
Lang Hames
ffd1326ff8 Improved tracking of value number kills. VN kills are now represented
as an (index,bool) pair. The bool flag records whether the kill is a
PHI kill or not. This code will be used to enable splitting of live
intervals containing PHI-kills.

A slight change to live interval weights introduced an extra spill
into lsr-code-insertion (outside the critical sections). The test 
condition has been updated to reflect this.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75097 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-09 03:57:02 +00:00
Lang Hames
98d5982e00 Fixed a bug in LiveInterval scaling (failure to scale VNI defs correctly), removed old TODO comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74054 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-24 02:17:32 +00:00
Lang Hames
857c4e01f8 VNInfo cleanup.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73634 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-17 21:01:20 +00:00
Evan Cheng
358dec5180 Part 1.
- Change register allocation hint to a pair of unsigned integers. The hint type is zero (which means prefer the register specified as second part of the pair) or entirely target dependent.
- Allow targets to specify alternative register allocation orders based on allocation hint.

Part 2.
- Use the register allocation hint system to implement more aggressive load / store multiple formation.
- Aggressively form LDRD / STRD. These are formed *before* register allocation. It has to be done this way to shorten live interval of base and offset registers. e.g.
v1025 = LDR v1024, 0
v1026 = LDR v1024, 0
=>
v1025,v1026 = LDRD v1024, 0

If this transformation isn't done before allocation, v1024 will overlap v1025 which means it more difficult to allocate a register pair.

- Even with the register allocation hint, it may not be possible to get the desired allocation. In that case, the post-allocation load / store multiple pass must fix the ldrd / strd instructions. They can either become ldm / stm instructions or back to a pair of ldr / str instructions.

This is work in progress, not yet enabled.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73381 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-15 08:28:29 +00:00
Evan Cheng
90f95f88c6 Move register allocation preference (or hint) from LiveInterval to MachineRegisterInfo. This allows more passes to set them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73346 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-14 20:22:55 +00:00
Lang Hames
f41538d1b5 Update to in-place spilling framework. Includes live interval scaling and trivial rewriter.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72729 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-02 16:53:25 +00:00
Evan Cheng
30590f5023 Fix PR4034. Bug in LiveInterval::join when it's compacting new valno's.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70291 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-28 06:24:09 +00:00
Evan Cheng
27e4666c20 Also delete last unused val#.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70212 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-27 17:35:19 +00:00
Evan Cheng
a4b2bab233 Reuse unused val#'s to avoid running out of memory in extreme cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70069 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-25 20:20:15 +00:00
Evan Cheng
0adb527d16 Do not share a single unknown val# for all the live ranges merged into a physical sub-register live interval. When coalescer is merging in clobbered virtaul register live interval into a physical register live interval, give each virtual register val# a separate val# in the physical register live interval. Otherwise, the coalescer would have lost track of the definitions information it needs to make correct coalescing decisions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70026 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-25 09:25:19 +00:00
Evan Cheng
cccdb2b602 Add a new LiveInterval::overlaps(). It checks if the live interval overlaps a range specified by [Start, End).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69434 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-18 08:52:15 +00:00
Dan Gohman
97121ba2af Implement support for using modeling implicit-zero-extension on x86-64
with SUBREG_TO_REG, teach SimpleRegisterCoalescing to coalesce
SUBREG_TO_REG instructions (which are similar to INSERT_SUBREG
instructions), and teach the DAGCombiner to take advantage of this on
targets which support it. This eliminates many redundant
zero-extension operations on x86-64.

This adds a new TargetLowering hook, isZExtFree. It's similar to
isTruncateFree, except it only applies to actual definitions, and not
no-op truncates which may not zero the high bits.

Also, this adds a new optimization to SimplifyDemandedBits: transform
operations like x+y into (zext (add (trunc x), (trunc y))) on targets
where all the casts are no-ops. In contexts where the high part of the
add is explicitly masked off, this allows the mask operation to be
eliminated. Fix the DAGCombiner to avoid undoing these transformations
to eliminate casts on targets where the casts are no-ops.

Also, this adds a new two-address lowering heuristic. Since
two-address lowering runs before coalescing, it helps to be able to
look through copies when deciding whether commuting and/or
three-address conversion are profitable.

Also, fix a bug in LiveInterval::MergeInClobberRanges. It didn't handle
the case that a clobber range extended both before and beyond an
existing live range. In that case, multiple live ranges need to be
added. This was exposed by the new subreg coalescing code.

Remove 2008-05-06-SpillerBug.ll. It was bugpoint-reduced, and the
spiller behavior it was looking for no longer occurrs with the new
instruction selection.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68576 91177308-0d34-0410-b5e6-96231b3b80d8
2009-04-08 00:15:30 +00:00
Evan Cheng
a2e6435e48 Two coalescer fixes in one.
1. Use the same value# to represent unknown values being merged into sub-registers.
2. When coalescer commute an instruction and the destination is a physical register, update its sub-registers by merging in the extended ranges.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66610 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-11 00:03:21 +00:00
Owen Anderson
5b93f6fa82 MergeValueInto is too smart: it might choose to do the merge the opposite direction.
Live interval reconstruction needs to account for this, and scour its maps to
prevent dangling references.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63558 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-02 22:42:01 +00:00
Evan Cheng
5a3c6a87b0 Exit with nice warnings when register allocator run out of registers.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63267 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-29 02:20:59 +00:00
Evan Cheng
42cc6e33ec Fix comment about removeRange.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63255 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-29 00:06:09 +00:00
Dale Johannesen
86b49f8e2d Next round of earlyclobber handling. Approach the
RA problem by expanding the live interval of an
earlyclobber def back one slot.  Remove
overlap-earlyclobber throughout.  Remove 
earlyclobber bits and their handling from
live internals.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56539 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-24 01:07:17 +00:00
Dale Johannesen
fa48f94130 Remove AsmThatEarlyClobber etc. from LiveIntervalAnalysis
and redo as linked list walk.  Logic moved into RA.
Per review feedback.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56326 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-19 01:02:35 +00:00
Dan Gohman
a8c763b307 Use empty() instead of begin() == end().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54780 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-14 18:13:49 +00:00