Commit Graph

276 Commits

Author SHA1 Message Date
Evan Cheng
1015ba7018 - Change MachineInstr::findRegisterDefOperandIdx so it can also look for defs
that are aliases of the specified register.
- Rename modifiesRegister to definesRegister since it's looking a def of the
specific register or one of its super-registers. It's not looking for def of a
sub-register or alias that could change the specified register.
- Added modifiesRegister to look for defs of aliases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104377 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-21 20:53:24 +00:00
Bob Wilson
417d1705bb Fix a crash when debugging the coalescer. DebugValue instructions are not
in the coalescer's instruction map.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104086 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 23:19:42 +00:00
Evan Cheng
31b9c44cc1 It's not safe eliminate copies where src and dst have different sub-register indices.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103450 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-11 00:20:03 +00:00
Evan Cheng
62bb2f63f9 Fixes a coalescer bug that caused llc to crash on 2009-11-30-LiveVariablesBug.ll
with the fix in 103157.

%reg1039:1<def> = VMOVS %S1<kill>, pred:14, pred:%reg0
is not coalescable since none of the super-registers of S1 are in reg1039's
register class: DPR_VFP2. But it is still a legal copy instruction so it should
not assert.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103170 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-06 06:23:31 +00:00
Jakob Stoklund Olesen
b98c549d13 Check that subregisters don't have independent values in RemoveCopyByCommutingDef().
This fixes PR6941.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102970 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-03 22:40:32 +00:00
Jakob Stoklund Olesen
132dace4aa Don't use floating point in SimpleRegisterCoalescing.
Rounding differences causes tests to fail on Linux.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102729 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-30 18:28:11 +00:00
Jakob Stoklund Olesen
f07fc974d3 Reject really weird coalescer case when trying to merge identical subregisters
of different register classes. e.g.

  %reg1048:3<def> = EXTRACT_SUBREG %RAX<kill>, 3

Where %reg1048 is a GR32 register. This is not impossible to handle, but it is
pretty hard and very rare.

This should unbreak the dragonegg builder.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102672 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-29 23:47:46 +00:00
Dan Gohman
a555ac9d15 Fix typos in assertion strings.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102666 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-29 23:25:34 +00:00
Jakob Stoklund Olesen
02104df05f Slightly verboser debug spew from coalescer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102663 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-29 22:21:48 +00:00
Jakob Stoklund Olesen
0fd109963a Recompute kill flags from live intervals after coalescing instead of trying to
update them. Computing kill flags is notoriously difficult, and the coalescer
would get it wrong sometimes, and it would completely skip physical registers.

Now we simply remove kill flags based on the live intervals after coalescing.
This is a few percent slower, but now we get correct kill flags for physical
registers after coalescing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102510 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-28 18:28:39 +00:00
Evan Cheng
e3dd8550c6 Do not try to optimize a copy that has already been marked for deletion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102027 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-21 20:57:54 +00:00
Evan Cheng
30fdb5c2ac - Clean up some crappy code which deals with coalescing of copies which look at
extract_subreg / insert_subreg, etc.
- Add support for more aggressive insert_subreg coalescing.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101971 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-21 00:44:22 +00:00
Evan Cheng
a57fabe815 Coalescer should not delete copy instructions whose defs are partially dead. e.g.
%RDI<def,dead> = MOV64rr %RAX<kill>, %EDI<imp-def>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100804 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-08 20:02:37 +00:00
Evan Cheng
9f68948609 Try trivial remat before the coalescer gives up on a vr / physreg coalescing for fear of tying up a physical register.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99575 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-26 00:07:25 +00:00
Evan Cheng
460e479b19 Code clean up.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99544 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-25 19:46:11 +00:00
Evan Cheng
fd59f4cd3d Remove an unused option.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99537 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-25 18:37:23 +00:00
Evan Cheng
48f2cb926e Avoid being influenced by dbg_value instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99465 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-25 01:01:37 +00:00
Jeffrey Yasskin
6b4c12db13 Free SavedLI even if SimpleRegisterCoalescing::JoinCopy() returns early.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@99113 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-21 01:47:49 +00:00
Jakob Stoklund Olesen
ec1176a206 Revert "Change coalescer complexity from N^2 to N logN by changing one letter."
This reverts commit 98776. It broke the llvm-gcc boot strap.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98784 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-18 00:23:47 +00:00
Jakob Stoklund Olesen
0427b2ac45 Change coalescer complexity from N^2 to N logN by changing one letter.
Remove ugly hack that aborted the coalescer before using N^2 time.

This affects functions with very complicated live intervals for physical
registers, i.e. functions with thousands of function calls.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98776 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-17 23:21:58 +00:00
Evan Cheng
826cbac2a0 The check for coalescing a virtual register to a physical register, e.g.
cl = EXTRACT_SUBREG reg1024, 1, is overly conservative. It should check
for overlaps of vr's live interval with the super registers of the
physical register (ECX in this case) and let JoinIntervals() handle checking
the coalescing feasibility against the physical register (cl in this case).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98251 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-11 08:20:21 +00:00
Jakob Stoklund Olesen
35071a0847 Disable physical register coalescing when the number of live ranges for the
physreg becomes ridiculously high.

std::upper_bound may be log(N), but for sufficiently large live intervals, it
becomes log(N)*cachemiss = a long long time.

This patch improves coalescer time by 4500x for a function with 20000
function calls. The generated code is different, but not significantly worse -
the allocator hints are almost as good as physreg coalescing anyway.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98023 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-09 00:59:48 +00:00
Evan Cheng
ac1abde05b Swap parameters of isSafeToMove and isSafeToReMat for consistency.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97578 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-02 19:03:01 +00:00
Jakob Stoklund Olesen
450986db96 Remember to handle sub-registers when moving imp-defs to a rematted instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96995 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-23 22:44:02 +00:00
Jakob Stoklund Olesen
b1ce7b1324 Enable assertion to detect cyclic valno references.
This changes the stack overflow in PR6363 to an assertion failure.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96744 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-21 18:51:48 +00:00
Jakob Stoklund Olesen
d135f14f61 Fix PR6283.
When coalescing with a physreg, remember to add imp-def and imp-kill when
dealing with sub-registers.

Also fix a related bug in VirtRegRewriter where substitutePhysReg may
reallocate the operand list on an instruction and invalidate the reg_iterator.
This can happen when a register is mentioned twice on the same instruction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96072 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-13 02:06:10 +00:00
Jakob Stoklund Olesen
4a540f0593 Reapply coalescer fix for better cross-class coalescing.
This time with fixed test cases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95938 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-11 23:55:29 +00:00
Jakob Stoklund Olesen
9637dd50f4 Revert functional change. This broke a bunch of tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95921 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-11 21:19:44 +00:00
Jakob Stoklund Olesen
a875fd0fdb It is always good to do a cross-class join when the large register has a tiny interval.
Also avoid division by zero.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95917 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-11 20:58:45 +00:00
Dale Johannesen
99efcf299f Ignore debug info one more place during coalescing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95819 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-10 23:04:09 +00:00
Dan Gohman
f451cb870e Fix "the the" and similar typos.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95781 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-10 16:03:48 +00:00
Dale Johannesen
bd63520161 Skip DBG_VALUE many places in live intervals and
register coalescing.  This fixes many crashes and
places where debug info affects codegen (when
dbg.value is lowered to machine instructions, which
it isn't yet in TOT).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95739 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-10 00:55:42 +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
Jakob Stoklund Olesen
00350dbd71 Remember to update live-in lists when coalescing physregs.
Patch by M Wahab!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95668 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-09 17:20:11 +00:00
David Greene
32edbd7454 Change errs() to dbgs().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92592 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 01:25:58 +00:00
Jakob Stoklund Olesen
4b6677f1c6 Add coalescer asserts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91945 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-22 23:54:54 +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
Evan Cheng
ac94863a1c Coalesce insert_subreg undef, x first to avoid phase ordering issue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91103 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-11 06:01:00 +00:00
Evan Cheng
6fd78ec8a2 It's not safe to coalesce a move where src and dst registers have different subregister indices. e.g.:
%reg16404:1<def> = MOV8rr %reg16412:2<kill>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91061 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-10 20:59:45 +00:00
Chris Lattner
7896c9f436 improve portability to avoid conflicting with std::next in c++'0x.
Patch by Howard Hinnant!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90365 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-03 00:50:42 +00:00
Evan Cheng
9836a26da3 Fix PR5391: support early clobber physical register def tied with a use (ewwww)
- A valno should be set HasRedefByEC if there is an early clobber def in the middle of its live ranges. It should not be set if the def of the valno is defined by an early clobber.
- If a physical register def is tied to an use and it's an early clobber, it just means the HasRedefByEC is set since it's still one continuous live range.
- Add a couple of missing checks for HasRedefByEC in the coalescer. In general, it should not coalesce a vr with a physical register if the physical register has a early clobber def somewhere. This is overly conservative but that's the price for using such a nasty inline asm "feature".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90269 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-01 22:25:00 +00:00
Jakob Stoklund Olesen
579d6d9fe3 Use CFG connectedness as a secondary sort key when deciding the order of copy coalescing.
This means that well connected blocks are copy coalesced before the less connected blocks. Connected blocks are more difficult to
coalesce because intervals are more complicated, so handling them first gives a greater chance of success.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90194 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-01 03:03:00 +00:00
Jakob Stoklund Olesen
324da7647c Add MachineBasicBlock::getName, and use it in place of getBasicBlock()->getName.
Fix debug code that assumes getBasicBlock never returns NULL.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89428 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-20 01:17:03 +00:00
Evan Cheng
d57cdd5683 - Change TargetInstrInfo::reMaterialize to pass in TargetRegisterInfo.
- If destination is a physical register and it has a subreg index, use the
  sub-register instead.
This fixes PR5423.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88745 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-14 02:55:43 +00:00
Evan Cheng
50608bac2f RangeIsDefinedByCopyFromReg() should check for subreg_to_reg, insert_subreg,
and extract_subreg as a "copy" that defines a valno.
Also fixes a typo. These two issues prevent a simple subreg coalescing from
happening before.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86022 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-04 08:33:14 +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
788fa17af8 Stop the iterator in ValueLiveAt from potentially running off the end of the interval.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85599 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-30 18:12:09 +00:00
Bill Wendling
a33ac6a4c1 Reapply r85338.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85514 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-29 17:39:46 +00:00
Bill Wendling
f58898fd41 Reverting r85338 for now. It's causing a bootstrap failure on PPC darwin9.
--- Reverse-merging r85338 into '.':
U    lib/CodeGen/SimpleRegisterCoalescing.cpp
U    lib/CodeGen/SimpleRegisterCoalescing.h



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85454 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-29 00:22:16 +00:00