Commit Graph

55 Commits

Author SHA1 Message Date
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
Mike Stump
fe095f39e7 Restore minor deletion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70892 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-04 18:40:41 +00:00
Evan Cheng
c781a243a3 In some rare cases, the register allocator can spill registers but end up not utilizing registers at all. The fundamental problem is linearscan's backtracking can end up freeing more than one allocated registers. However, reloads and restores might be folded into uses / defs and freed registers might not be used at all.
VirtRegMap keeps track of allocations so it knows what's not used. As a horrible hack, the stack coloring can color spill slots with *free* registers. That is, it replace reload and spills with copies from and to the free register. It unfold instructions that load and store the spill slot and replace them with register using variants.

Not yet enabled. This is part 1. More coming.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70787 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-03 18:32:42 +00:00
Bill Wendling
e67f5e4273 Oy! When reverting r68073, I added in experimental code. Sorry...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68099 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-31 08:41:31 +00:00
Bill Wendling
8fe00540fc Revert r68073. It's causing a failure in the Apple-style builds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@68092 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-31 08:26:26 +00:00
Owen Anderson
49c8aa0d8b Convert VirtRegMap to a MachineFunctionPass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66870 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-13 05:55:11 +00:00
Owen Anderson
1ed5b714f1 Reorganization: Move the Spiller out of VirtRegMap.cpp into its own files. No (intended) functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66720 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-11 22:31:21 +00:00
Dan Gohman
d68a07650c Tidy up #includes, deleting a bunch of unnecessary #includes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61715 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-05 17:59:02 +00:00
Evan Cheng
cb74266cdb Move #include to right place.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51932 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-04 09:16:33 +00:00
Evan Cheng
4cce6b4c78 Use of implicit_def is not part of live interval. Create empty intervals for the uses when the live interval is being spilled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49542 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-11 17:53:36 +00:00
Dan Gohman
39e33acf0a Fix typos in comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48297 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-12 20:50:04 +00:00
Evan Cheng
c1f53c7426 Transfer physical register spill info when load / store folding happens.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48246 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-11 21:34:46 +00:00
Evan Cheng
676dd7c80b When the register allocator runs out of registers, spill a physical register around the def's and use's of the interval being allocated to make it possible for the interval to target a register and spill it right away and restore a register for uses. This likely generates terrible code but is before than aborting.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48218 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-11 07:19:34 +00:00
Evan Cheng
d36531249a Spiller now remove unused spill slots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47657 91177308-0d34-0410-b5e6-96231b3b80d8
2008-02-27 03:04:06 +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
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
d120ffd26f MachineInstr can change. Store indexes instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44612 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-05 10:24:35 +00:00
Evan Cheng
adf8590690 If a split live interval is spilled again, remove the kill marker on its last use.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44611 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-05 09:51:10 +00:00
Evan Cheng
b50bb8cf19 Fix kill info for split intervals.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44609 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-05 08:16:32 +00:00
Evan Cheng
aee4af68ae Remove redundant foldMemoryOperand variants and other code clean up.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44517 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-02 08:30:39 +00:00
Evan Cheng
0cbb1164b3 Fixed various live interval splitting bugs / compile time issues.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44428 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-29 01:06:25 +00:00
Evan Cheng
cada245d06 Recover compile time regression.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44386 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-28 01:28:46 +00:00
Evan Cheng
81a0382181 Live interval splitting:
When a live interval is being spilled, rather than creating short, non-spillable
intervals for every def / use, split the interval at BB boundaries. That is, for
every BB where the live interval is defined or used, create a new interval that
covers all the defs and uses in the BB.

This is designed to eliminate one common problem: multiple reloads of the same
value in a single basic block. Note, it does *not* decrease the number of spills
since no copies are inserted so the split intervals are *connected* through
spill and reloads (or rematerialization). The newly created intervals can be
spilled again, in that case, since it does not span multiple basic blocks, it's
spilled in the usual manner. However, it can reuse the same stack slot as the
previously split interval.

This is currently controlled by -split-intervals-at-bb.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44198 91177308-0d34-0410-b5e6-96231b3b80d8
2007-11-17 00:40:40 +00:00
Evan Cheng
7f56625447 Local spiller optimization:
Turn this:
movswl  %ax, %eax
movl    %eax, -36(%ebp)
xorl    %edi, -36(%ebp)
into
movswl  %ax, %eax
xorl    %edi, %eax
movl    %eax, -36(%ebp)
by unfolding the load / store xorl into an xorl and a store when we know the
value in the spill slot is available in a register. This doesn't change the
number of instructions but reduce the number of times memory is accessed.

Also unfold some load folding instructions and reuse the value when similar
situation presents itself.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@42947 91177308-0d34-0410-b5e6-96231b3b80d8
2007-10-13 02:50:24 +00:00
Evan Cheng
549f27d307 Re-implement trivial rematerialization. This allows def MIs whose live intervals that are coalesced to be rematerialized.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41060 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-13 23:45:17 +00:00
David Greene
7e23146ab9 Add a missing forward declaration.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40896 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-07 16:34:05 +00:00
Dan Gohman
61e729e2e9 More explicit keywords.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@40757 91177308-0d34-0410-b5e6-96231b3b80d8
2007-08-02 21:21:54 +00:00
Evan Cheng
9193514e2e Re-materialize all loads from fixed stack slots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35660 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-04 07:40:01 +00:00
Evan Cheng
2638e1a6b9 First cut trivial re-materialization support.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35208 91177308-0d34-0410-b5e6-96231b3b80d8
2007-03-20 08:13:50 +00:00
Chris Lattner
94c002a190 rename DenseMap to IndexedMap.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33749 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-01 05:32:05 +00:00
Bill Wendling
5c7e326585 Added an automatic cast to "std::ostream*" etc. from OStream. We then can
rework the hacks that had us passing OStream in. We pass in std::ostream*
instead, check for null, and then dispatch to the correct print() method.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32636 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-17 05:15:13 +00:00
Bill Wendling
e81561909d Changed llvm_ostream et all to OStream. llvm_cerr, llvm_cout, llvm_null, are
now cerr, cout, and NullStream resp.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32298 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-07 01:30:32 +00:00
Bill Wendling
b2b9c20b61 More removal of std::cerr and DEBUG, replacing with DOUT instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31806 91177308-0d34-0410-b5e6-96231b3b80d8
2006-11-17 02:09:07 +00:00
Chris Lattner
2926869b4a Fix a long-standing wart in the code generator: two-address instruction lowering
actually *removes* one of the operands, instead of just assigning both operands
the same register.  This make reasoning about instructions unnecessarily complex,
because you need to know if you are before or after register allocation to match
up operand #'s with the target description file.

Changing this also gets rid of a bunch of hacky code in various places.

This patch also includes changes to fold loads into cmp/test instructions in
the X86 backend, along with a significant simplification to the X86 spill
folding code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30108 91177308-0d34-0410-b5e6-96231b3b80d8
2006-09-05 02:12:02 +00:00
Chris Lattner
229924a79f Fix a latent bug that my spiller patch last week exposed: we were leaving
instructions in the virtregfolded map that were deleted.  Because they
were deleted, newly allocated instructions could end up at the same address,
magically finding themselves in the map.  The solution is to remove entries
from the map when we delete the instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28041 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-01 22:03:24 +00:00
Chris Lattner
35f2705e3d Remove previous patch, which wasn't quite right.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28039 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-01 21:16:03 +00:00
Evan Cheng
200370fb56 Local spiller kills a store if the folded restore is turned into a copy.
But this is incorrect if the spilled value live range extends beyond the
current BB.
It is currently controlled by a temporary option -spiller-check-liveout.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28024 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-30 08:41:47 +00:00
Misha Brukman
edf128a7fa Remove trailing whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21420 91177308-0d34-0410-b5e6-96231b3b80d8
2005-04-21 22:36:52 +00:00
Chris Lattner
bec6a9ea12 When a virtual register is folded into an instruction, keep track of whether
it was a use, def, or both.  This allows us to be less pessimistic in our
analysis of them.  In practice, this doesn't make a big difference, but it
doesn't hurt either.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16632 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-01 23:15:36 +00:00
Alkis Evlogimenos
c736b3a37a Document this class a bit :-)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16626 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-01 00:35:07 +00:00
Chris Lattner
7f690e6258 Use longer and more explicit names for instance vars (particularly important
data structures).  Fix the print method to send to the right ostream, not
always cerr.  Delete typedefs that are only used once.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16606 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-30 02:15:18 +00:00
Chris Lattner
8c4d88d369 Reindent code, improve comments, move huge nested methods out of classes,
prune #includes, add print/dump methods, etc.  No functionality changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16604 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-30 01:54:45 +00:00
Reid Spencer
551ccae044 Changes For Bug 352
Move include/Config and include/Support into include/llvm/Config,
include/llvm/ADT and include/llvm/Support. From here on out, all LLVM
public header files must be under include/llvm/.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16137 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-01 22:55:40 +00:00
Alkis Evlogimenos
a39fc0efcf Add function to clear all virtual->physical mappings but not assigned
stack slots. This is in preparation for the iterative linear scan.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15032 91177308-0d34-0410-b5e6-96231b3b80d8
2004-07-20 13:28:17 +00:00
Alkis Evlogimenos
38af59a43c Add method to assign stack slot to virtual register without creating a
new one.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13895 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-29 20:38:05 +00:00
Alkis Evlogimenos
f174cc303b Add grow() member that grows the maps when the number of virtual
registers in the function has changed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@13893 91177308-0d34-0410-b5e6-96231b3b80d8
2004-05-29 19:03:29 +00:00
Alkis Evlogimenos
dd420e060a Add a spiller option to llc. A simple spiller will come soon. When we get CFG in the machine code represenation a global spiller will also be possible. Also document the linear scan register allocator but mark it as experimental for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12062 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-01 23:18:15 +00:00
Alkis Evlogimenos
5f37502bfb Add the long awaited memory operand folding support for linear scan
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12058 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-01 20:05:10 +00:00
Alkis Evlogimenos
fc54e83cea Rename member function to be consistent with the rest.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11898 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-27 06:11:15 +00:00
Alkis Evlogimenos
4d0d864be3 Add DenseMap template and actually use it for for mapping virtual regs
to objects.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11840 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-25 21:55:45 +00:00