Commit Graph

34 Commits

Author SHA1 Message Date
Benjamin Kramer
4eed756153 Switch spill weights from a basic loop depth estimation to BlockFrequencyInfo.
The main advantages here are way better heuristics, taking into account not
just loop depth but also __builtin_expect and other static heuristics and will
eventually learn how to use profile info. Most of the work in this patch is
pushing the MachineBlockFrequencyInfo analysis into the right places.

This is good for a 5% speedup on zlib's deflate (x86_64), there were some very
unfortunate spilling decisions in its hottest loop in longest_match(). Other
benchmarks I tried were mostly neutral.

This changes register allocation in subtle ways, update the tests for it.
2012-02-20-MachineCPBug.ll was deleted as it's very fragile and the instruction
it looked for was gone already (but the FileCheck pattern picked up unrelated
stuff).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184105 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-17 19:00:36 +00:00
Nadav Rotem
6e01dcbb73 typo
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178949 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-06 04:24:12 +00:00
Jakob Stoklund Olesen
790047620a Remove LIS::isAllocatable() and isReserved() helpers.
All callers can simply use the corresponding MRI functions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165985 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-15 22:14:34 +00:00
David Blaikie
986d76d7b3 Tidy up a few more uses of MF.getFunction()->getName().
Based on CR feedback from r162301 and Craig Topper's refactoring in r162347
here are a few other places that could use the same API (& in one instance drop
a Function.h dependency).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162367 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-22 17:18:53 +00:00
Craig Topper
96601ca332 Add a getName function to MachineFunction. Use it in places that previously did getFunction()->getName(). Remove includes of Function.h that are no longer needed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162347 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-22 06:07:19 +00:00
Jakob Stoklund Olesen
d67582e276 Avoid iterating with LiveIntervals::iterator.
That is a DenseMap iterator keyed by pointers, so the iteration order is
nondeterministic.

I would like to replace the DenseMap with an IndexedMap which doesn't
allow iteration.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158856 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-20 21:25:05 +00:00
Jakob Stoklund Olesen
3dfd59bdc3 Stop using LiveIntervals::isReMaterializable().
It is an old function that does a lot more than required by
CalcSpillWeights, which was the only remaining caller.

The isRematerializable() function never actually sets the isLoad
argument, so don't try to compute that.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157973 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-05 01:06:12 +00:00
Jakob Stoklund Olesen
6d1fd0b979 Move CalculateRegClass to MRI::recomputeRegClass.
This function doesn't have anything to do with spill weights, and MRI
already has functions for manipulating the register class of a virtual
register.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137123 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-09 16:46:27 +00:00
Jakob Stoklund Olesen
5e9ae090d8 Don't inflate register classes used by inline asm.
The constraints are represented by the register class of the original
virtual register created for the inline asm. If the register class were
included in the operand descriptor, we might be able to do this.

For now, just give up on regclass inflation when inline asm is involved.

No test case, this bug hasn't happened yet.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134226 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-01 01:24:25 +00:00
Evan Cheng
15993f83a4 More refactoring. Move getRegClass from TargetOperandInfo to TargetInstrInfo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133944 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-27 21:26:13 +00:00
Jakob Stoklund Olesen
f5497fb1b4 Teach LiveInterval::isZeroLength about null SlotIndexes.
When instructions are deleted, they leave tombstone SlotIndex entries.
The isZeroLength method should ignore these null indexes.

This causes RABasic to sometimes spill a callee-saved register in the
abi-isel.ll test, so don't run that test with -regalloc=basic.  Prioritizing
register allocation according to spill weight can cause more registers to be
used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131436 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-16 23:50:05 +00:00
Jakob Stoklund Olesen
1394e6d925 Use the new TRI->getLargestLegalSuperClass hook to constrain register class inflation.
This has two effects: 1. We never inflate to a larger register class than what
the sub-target can handle. 2. Completely unconstrained virtual registers get the
largest possible register class.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130229 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-26 18:52:36 +00:00
Jakob Stoklund Olesen
6094bd87d8 Recompute register class and hint for registers created during spilling.
The spill weight is not recomputed for an unspillable register - it stays infinite.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128490 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-29 21:20:19 +00:00
Jakob Stoklund Olesen
38f6bd0fc8 Make SpillIs an optional pointer. Avoid creating a bunch of temporary SmallVectors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127388 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-10 01:21:58 +00:00
Jakob Stoklund Olesen
eb9f040f0d Move more fragments of spill weight calculation into CalcSpillWeights.h
Simplify the spill weight calculation a bit by bypassing
getApproximateInstructionCount() and using LiveInterval::getSize() directly.
This changes the computed spill weights, but only by a constant factor in each
function. It should not affect how spill weights compare against each other, and
so it shouldn't affect code generation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125530 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-14 23:15:38 +00:00
Jakob Stoklund Olesen
4314268128 Replace TargetRegisterInfo::printReg with a PrintReg class that also works without a TRI instance.
Print virtual registers numbered from 0 instead of the arbitrary
FirstVirtualRegister. The first virtual register is printed as %vreg0.
TRI::NoRegister is printed as %noreg.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123107 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-09 03:05:53 +00:00
Owen Anderson
2ab36d3502 Begin adding static dependence information to passes, which will allow us to
perform initialization without static constructors AND without explicit initialization
by the client.  For the moment, passes are required to initialize both their
(potential) dependencies and any passes they preserve.  I hope to be able to relax
the latter requirement in the future.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116334 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-12 19:48:12 +00:00
Owen Anderson
ce665bd2e2 Now with fewer extraneous semicolons!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115996 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-07 22:25:06 +00:00
Jakob Stoklund Olesen
e1f543fbb3 Clean up debug output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110940 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-12 18:50:55 +00:00
Jakob Stoklund Olesen
a516e94cf1 Give up on register class recalculation when the register is used with subreg
operands. We don't currently have a hook to provide "the largest super class of
A where all registers' getSubReg(subidx) is valid and in B".

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110730 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-10 21:16:16 +00:00
Jakob Stoklund Olesen
9db3ea46cb Implement register class inflation.
When splitting a live range, the new registers have fewer uses and the
permissible register class may be less constrained. Recompute the register class
constraint from the uses of new registers created for a split. This may let them
be allocated from a larger set, possibly avoiding a spill.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110703 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-10 18:37:40 +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
Owen Anderson
d13db2c59c Fix batch of converting RegisterPass<> to INTIALIZE_PASS().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109045 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-21 22:09:45 +00:00
Jakob Stoklund Olesen
af462c4b4f Remove remaining calls to TII::isMoveInstr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108556 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-16 21:03:55 +00:00
Eric Christopher
00e840f469 Fix typo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107556 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-03 01:09:18 +00:00
Jakob Stoklund Olesen
352d352c02 Always normalize spill weights, also for intervals created by spilling.
Moderate the weight given to very small intervals.

The spill weight given to new intervals created when spilling was not
normalized in the same way as the original spill weights calculated by
CalcSpillWeights. That meant that restored registers would tend to hang around
because they had a much higher spill weight that unspilled registers.

This improves the runtime of a few tests by up to 10%, and there are no
significant regressions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96613 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-18 21:33:05 +00:00
Evan Cheng
1e5cc222e8 Remove duplicated #include.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95747 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-10 01:22:57 +00:00
Evan Cheng
8112b5322e Emit an error for illegal inline asm constraint (which uses illegal type) rather than asserting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95746 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-10 01:21:02 +00:00
Chris Lattner
3143e90ca8 fix missing #includes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95745 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-10 01:17:36 +00:00
Chris Lattner
518bb53485 move target-independent opcodes out of TargetInstrInfo
into TargetOpcodes.h.  #include the new TargetOpcodes.h
into MachineInstr.  Add new inline accessors (like isPHI())
to MachineInstr, and start using them throughout the 
codebase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95687 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-09 19:54:29 +00:00
Dale Johannesen
d94998f525 Skip DEBUG_VALUE in some places where it was affecting codegen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95647 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-09 02:01:46 +00:00
David Greene
7ed6dd61ac Change errs() to dbgs().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92099 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-24 00:39:02 +00:00
Lang Hames
74ab5eeffb Changed slot index ranges for MachineBasicBlocks to be exclusive of endpoint.
This fixes an in-place update bug where code inserted at the end of basic blocks may not be covered by existing intervals which were live across the entire block. It is also consistent with the way ranges are specified for live intervals.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91859 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-22 00:11:50 +00:00
Lang Hames
a937f220e1 Moved spill weight calculation out of SimpleRegisterCoalescing and into its own pass: CalculateSpillWeights.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91273 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-14 06:49:42 +00:00