Commit Graph

24 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen
806562cc59 Remember to set flag.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129579 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-15 17:24:46 +00:00
Jakob Stoklund Olesen
1edc3cf65d Don't shrink live ranges after dead code elimination unless it is going to help.
In particular, don't repeatedly recompute the PIC base live range after rematerialization.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129275 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-11 15:00:39 +00:00
Jakob Stoklund Olesen
3520019931 When dead code elimination removes all but one use, try to fold the single def into the remaining use.
Rematerialization can leave single-use loads behind that we might as well fold whenever possible.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128918 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-05 20:20:26 +00:00
Jakob Stoklund Olesen
f22ca3fe5f Treat clones the same as their origin.
When DCE clones a live range because it separates into connected components,
make sure that the clones enter the same register allocator stage as the
register they were cloned from.

For instance, clones may be split even when they where created during spilling.
Other registers created during spilling are not candidates for splitting or even
(re-)spilling.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128524 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-30 02:52:39 +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
cf610d07de Remember to use the correct register when rematerializing for snippets.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128469 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-29 17:47:02 +00:00
Jakob Stoklund Olesen
2ef661b0e8 Properly enable rematerialization when spilling after live range splitting.
The instruction to be rematerialized may not be the one defining the register
that is being spilled. The traceSiblingValue() function sees through sibling
copies to find the remat candidate.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128449 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-29 03:12:02 +00:00
Jakob Stoklund Olesen
1e6c65dba7 Notify the delegate before removing dead values from a live interval.
The register allocator needs to know when the range shrinks.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128145 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-23 04:43:16 +00:00
Jakob Stoklund Olesen
6a3dbd3b25 Dead code elimination may separate the live interval into multiple connected components.
I have convinced myself that it can only happen when a phi value dies. When it
happens, allocate new virtual registers for the components.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127827 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-17 20:37:07 +00:00
Jakob Stoklund Olesen
1d5b845081 Add a LiveRangeEdit delegate callback before shrinking a live range.
The register allocator needs to adjust its live interval unions when that happens.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127774 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-16 22:56:16 +00:00
Jakob Stoklund Olesen
cc5c4296fd Erase virtual registers that are unused after DCE.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127773 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-16 22:56:13 +00:00
Jakob Stoklund Olesen
c46570dc05 Clarify debugging output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127771 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-16 22:56:08 +00:00
Jakob Stoklund Olesen
7792e980c4 Tell the register allocator about new unused virtual registers.
This allows the allocator to free any resources used by the virtual register,
including physical register assignments.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127560 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-13 01:23:11 +00:00
Jakob Stoklund Olesen
92a55f4bdd Add a LiveRangeEdit::Delegate protocol.
This will we used for keeping register allocator data structures up to date
while LiveRangeEdit is trimming live intervals.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127300 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-09 00:57:29 +00:00
Jakob Stoklund Olesen
5881799d0c Delete dead code after rematerializing.
LiveRangeEdit::eliminateDeadDefs() will eventually be used by coalescing,
splitting, and spilling for dead code elimination. It can delete chains of dead
instructions as long as there are no dependency loops.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127287 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-08 22:46:11 +00:00
Jakob Stoklund Olesen
1973b3e254 Make the UselessRegs argument optional in the LiveRangeEdit constructor.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127181 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-07 22:42:16 +00:00
Jakob Stoklund Olesen
fd38917d4d This method belonged in VirtRegMap.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126002 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-19 00:38:43 +00:00
Jakob Stoklund Olesen
e324f6e05f Use VirtRegMap's Virt2SplitMap to keep track of the original live range before splitting.
All new virtual registers created for spilling or splitting point back to their original.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@125980 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-18 22:35:20 +00:00
Jakob Stoklund Olesen
b80e973c95 Simplify the LiveRangeEdit::canRematerializeAt() interface a bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118661 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-10 01:05:12 +00:00
Jakob Stoklund Olesen
a37d5cf342 Don't assign new registers created during a split to the same stack slot, but
give them individual stack slots once the are actually spilled.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117945 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-01 19:49:57 +00:00
Jakob Stoklund Olesen
f1583ae84a Remember to keep track of rematted values.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116962 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-20 22:50:42 +00:00
Jakob Stoklund Olesen
080c316ff8 Move some of the InlineSpiller rematerialization code into LiveRangeEdit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116951 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-20 22:00:51 +00:00
Jakob Stoklund Olesen
2a0180fbff Move stack slot assignments into LiveRangeEdit.
All registers created during splitting or spilling are assigned to the same
stack slot as the parent register.

When splitting or rematting, we may not spill at all. In that case the stack
slot is still assigned, but it will be dead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116546 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-15 00:16:55 +00:00
Jakob Stoklund Olesen
a17768f582 Create a new LiveRangeEdit class to keep track of the new registers created when
splitting or spillling, and to help with rematerialization.

Use LiveRangeEdit in InlineSpiller and SplitKit. This will eventually make it
possible to share remat code between InlineSpiller and SplitKit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116543 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-14 23:49:52 +00:00