Commit Graph

79 Commits

Author SHA1 Message Date
Evan Cheng 289ba4f335 Avoid commuting a def MI in order to coalesce a copy instruction away if any use of the same val# is a copy instruction that has already been coalesced.
llvm-svn: 48833
2008-03-26 19:03:01 +00:00
Evan Cheng 7d564c3b4a lastRegisterUse() should ignore identity copies. Those will be erased.
llvm-svn: 48759
2008-03-25 02:02:19 +00:00
Evan Cheng 69a3f9c417 If the coalescer commuted a def MI to allow coalescing, it can changed a previously coalesced copy into an non-identity copy.
llvm-svn: 48752
2008-03-24 23:31:21 +00:00
Evan Cheng 8c19af1b7e A couple of kill marker maintainence bug.
llvm-svn: 48653
2008-03-21 19:09:30 +00:00
Evan Cheng 56e9e57d28 Fixed a coalescer bug caused by a typo.
llvm-svn: 48526
2008-03-19 02:26:36 +00:00
Evan Cheng d096ec0a86 Rewrite code that propagate isDead information after a dead copy is coalesced. This remove some ugly spaghetti code and fixed a number of subtle bugs.
llvm-svn: 48490
2008-03-18 08:26:47 +00:00
Evan Cheng 4f610c0de1 Remove unused options.
llvm-svn: 48319
2008-03-13 02:41:34 +00:00
Evan Cheng 4a3c5eab34 - Fix a subtle bug in RemoveCopyByCommutingDef. ALR is the live range where the source is defined; BLR is the live range which is defined by the copy.
If ALR and BLR overlaps and end of BLR extends beyond end of ALR, e.g.                                                                                                 
 A = or A, B                                                                                                                                                            
 ...                                                                                                                                                                    
 B = A                                                                                                                                                                  
 ...                                                                                                                                                                    
 C = A<kill>                                                                                                                                                            
 ...                                                                                                                                                                    
   = B                                                                                                                                                                  
                                                                                                                                                                        
then do not add kills of A to the newly created B interval.
- Also fix some kill info update bug.

llvm-svn: 48141
2008-03-10 08:11:32 +00:00
Evan Cheng 29b502e0e0 Fix a coalescer bug wrt how dead copy interval is shortened.
llvm-svn: 47966
2008-03-05 22:09:42 +00:00
Evan Cheng 6325446666 Refactor code. Remove duplicated functions that basically do the same thing as
findRegisterUseOperandIdx, findRegisterDefOperandIndx. Fix some naming inconsistencies.

llvm-svn: 47927
2008-03-05 00:59:57 +00:00
Evan Cheng ca7c61e79a No need for coalescer to update kills. Only copies are coalesced and those instructions will be deleted. Doh.
llvm-svn: 47749
2008-02-29 02:50:03 +00:00
Bill Wendling d7a258d325 Rename PrintableName to Name.
llvm-svn: 47629
2008-02-26 21:47:57 +00:00
Bill Wendling c24ea4fb41 Change "Name" to "AsmName" in the target register info. Gee, a refactoring tool
would have been a Godsend here!

llvm-svn: 47625
2008-02-26 21:11:01 +00:00
Evan Cheng fa6b366892 Enable -coalescer-commute-instrs by default.
llvm-svn: 47623
2008-02-26 20:40:22 +00:00
Evan Cheng 2ff0b0e681 This is possible:
vr1 = extract_subreg vr2, 3
...
vr3 = extract_subreg vr1, 2
The end result is vr3 is equal to vr2 with subidx 2.

llvm-svn: 47592
2008-02-26 08:03:41 +00:00
Evan Cheng 271aef2b03 Fix compiler warning.
llvm-svn: 47468
2008-02-22 01:48:00 +00:00
Evan Cheng 31160f5b98 Help testing.
llvm-svn: 47448
2008-02-21 19:20:21 +00:00
Evan Cheng b2e4b7adde - Remove the previous check which broke coalescer-commute3.ll
- For now, conservatively ignore copy MI whose source is a physical register. Commuting its def MI can cause a physical register live interval to be live through a loop (since we know it's live coming into the def MI).

llvm-svn: 47281
2008-02-18 18:56:31 +00:00
Evan Cheng 8f90724a53 For now, avoid commuting def MI for copy MI's whose source is not killed. That simply trade a live interval for another and because only the non-two-address operands can be folded into loads, may end up pessimising code.
llvm-svn: 47262
2008-02-18 08:40:53 +00:00
Evan Cheng 652e4618e2 Refactor some code; check if commuteInstruction is able to commute the instruction.
llvm-svn: 47208
2008-02-16 02:32:17 +00:00
Evan Cheng 803bb6d699 The copy instruction being coalesced will be removed, it is not a kill.
llvm-svn: 47179
2008-02-15 21:36:51 +00:00
Evan Cheng 2ff2da89ab - Removing the infamous r2rMap_ and rep() method. Now the coalescer will update
register defs and uses after each successful coalescing.
- Also removed a number of hacks and fixed some subtle kill information bugs.

llvm-svn: 47167
2008-02-15 18:24:29 +00:00
Evan Cheng 587c66ed96 Some code clean up.
llvm-svn: 47060
2008-02-13 09:56:03 +00:00
Evan Cheng 8cc58728a8 * Cannot safely commute an instruction there are other defs which can reach its uses.
* Ignore copy instructions which have already been coalesced.

llvm-svn: 47056
2008-02-13 08:41:08 +00:00
Evan Cheng 1446726f3e Initial support for copy elimination by commuting its definition MI.
PR1877.
A3 = op A2 B0<kill>                                                                                                                                                                            
...                                                                                                                                                                                     
B1 = A3      <- this copy                                                                                                                                                                      
...                                                                                                                                                                                          
   = op A3   <- more uses                                                                                                                                                                      
                                                                                                                                                                                                 
==>                                                                                                                                                                                             
                                                                                                                                                                                            
B2 = op B0 A2<kill>                                                                                                                                                                            
...                                                                                                                                                                                          
B1 = B2      <- now an identify copy                                                                                                                                                           
...                                                                                                                                                                                          
   = op B2   <- more uses

This speeds up FreeBench/neural by 29%, Olden/bh by 12%, oopack_v1p8 by 53%.

llvm-svn: 47046
2008-02-13 03:01:43 +00:00
Dan Gohman 3a4be0fdef Rename MRegisterInfo to TargetRegisterInfo.
llvm-svn: 46930
2008-02-10 18:45:23 +00:00
Evan Cheng 6aabf837fe Remove unused hidden option.
llvm-svn: 46903
2008-02-09 08:36:28 +00:00
Bill Wendling 0c209430b4 Don't recalculate the loop info and loop dominators analyses if they're
preserved.

llvm-svn: 45596
2008-01-04 20:54:55 +00:00
Bill Wendling 118ae4cd61 80-column violations.
llvm-svn: 45574
2008-01-04 08:59:18 +00:00
Chris Lattner 21ec2b4769 update a couple of references to SSARegMap.
llvm-svn: 45468
2007-12-31 04:16:08 +00:00
Chris Lattner a10fff51d9 Rename SSARegMap -> MachineRegisterInfo in keeping with the idea
that "machine" classes are used to represent the current state of
the code being compiled.  Given this expanded name, we can start 
moving other stuff into it.  For now, move the UsedPhysRegs and
LiveIn/LoveOuts vectors from MachineFunction into it.

Update all the clients to match.

This also reduces some needless #includes, such as MachineModuleInfo
from MachineFunction.

llvm-svn: 45467
2007-12-31 04:13:23 +00:00
Chris Lattner 6005589faf More cleanups for MachineOperand:
- Eliminate the static "print" method for operands, moving it
    into MachineOperand::print.
  - Change various set* methods for register flags to take a bool
    for the value to set it to.  Remove unset* methods.
  - Group methods more logically by operand flavor in MachineOperand.h

llvm-svn: 45461
2007-12-30 21:56:09 +00:00
Chris Lattner f3ebc3f3d2 Remove attribution from file headers, per discussion on llvmdev.
llvm-svn: 45418
2007-12-29 20:36:04 +00:00
Evan Cheng a509537e25 The physical register + virtual register joining requirement was much too strict.
llvm-svn: 45253
2007-12-20 02:23:25 +00:00
Evan Cheng 303417d242 Switch over to MachineLoopInfo.
llvm-svn: 44838
2007-12-11 02:09:15 +00:00
Evan Cheng 85cdba29b0 Add an option to control this heuristic tweak so I can test it.
llvm-svn: 44671
2007-12-07 00:28:32 +00:00
Evan Cheng 7fc1d98353 Fix for PR1831: if all defs of an interval are re-materializable, then it's a preferred spill candiate.
llvm-svn: 44644
2007-12-06 00:01:56 +00:00
Evan Cheng f85c063ec0 Replace the odd kill# hack with something less fragile.
llvm-svn: 44434
2007-11-29 09:49:23 +00:00
Evan Cheng 8e22379303 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.

llvm-svn: 44198
2007-11-17 00:40:40 +00:00
Evan Cheng 7f02cfa599 Clean up sub-register implementation by moving subReg information back to
MachineOperand auxInfo. Previous clunky implementation uses an external map
to track sub-register uses. That works because register allocator uses
a new virtual register for each spilled use. With interval splitting (coming
soon), we may have multiple uses of the same register some of which are
of using different sub-registers from others. It's too fragile to constantly
update the information.

llvm-svn: 44104
2007-11-14 07:59:08 +00:00
Evan Cheng be51f28e2b Refactor some code.
llvm-svn: 44010
2007-11-12 06:35:08 +00:00
Evan Cheng d5d59ad634 First step towards moving the coalescer to priority_queue based machinery.
llvm-svn: 43764
2007-11-06 08:52:21 +00:00
Evan Cheng 8bb30184a8 Move SimpleRegisterCoalescing.h to lib/CodeGen since there is now a common
register coalescer interface: RegisterCoalescing.

llvm-svn: 43714
2007-11-05 17:41:38 +00:00
Evan Cheng 17b0e3e1ae Skip over deleted val#'s.
llvm-svn: 43700
2007-11-05 06:46:45 +00:00
Evan Cheng fe1ac52836 - Coalesce extract_subreg when both intervals are relatively small.
- Some code clean up.

llvm-svn: 43606
2007-11-01 06:22:48 +00:00
Evan Cheng e6a41c066a Really fix PR1734. Carefully track which register uses are sub-register uses by
traversing inverse register coalescing map.

llvm-svn: 43118
2007-10-18 07:49:59 +00:00
Evan Cheng c8b5397000 One more extract_subreg coalescing bug fix.
llvm-svn: 43065
2007-10-17 05:29:37 +00:00
Evan Cheng fab7ca89d5 Fix PR1734.
llvm-svn: 43035
2007-10-16 19:29:47 +00:00
Evan Cheng ecf62cb763 Code clean up.
llvm-svn: 43026
2007-10-16 08:04:24 +00:00
Evan Cheng a5abba65b6 Fix PR1729: watch out for val# with no def.
llvm-svn: 42996
2007-10-15 18:33:50 +00:00