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path: root/lib/CodeGen/SimpleRegisterCoalescing.cpp
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2009-10-27Fixed a bug in the coalescer where intervals were occasionally merged ↵Lang Hames
despite a real interference. This fixes rdar://problem/7157961. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85338 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-26- Revert some changes from 85044, 85045, and 85047 that broke x86_64 tests andEvan Cheng
bootstrapping. It's not safe to leave identity subreg_to_reg and insert_subreg around. - Relax register scavenging to allow use of partially "not-live" registers. It's common for targets to operate on registers where the top bits are undef. e.g. s0 = d0 = insert_subreg d0<undef>, s0, 1 ... = d0 When the insert_subreg is eliminated by the coalescer, the scavenger used to complain. The previous fix was to keep to insert_subreg around. But that's brittle and it's overly conservative when we want to use the scavenger to allocate registers. It's actually legal and desirable for other instructions to use the "undef" part of d0. e.g. s0 = d0 = insert_subreg d0<undef>, s0, 1 ... s1 = = s1 = d0 We probably need add a "partial-undef" marker on machine operand so the machine verifier would not complain. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85091 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-25Do not delete identity insert_subreg even if dest is virtual. Let later ↵Evan Cheng
passes delete them. This avoids register scavenger complain. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85045 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-24Rename isLoopExit to isLoopExiting, for consistency with the wordingDan Gohman
used elsewhere - an exit block is a block outside the loop branched to from within the loop. An exiting block is a block inside the loop that branches out. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85019 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-23Identity copies should not contribute to spill weight.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84978 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-09Factor out LiveIntervalAnalysis' code to determine whether an instructionDan Gohman
is trivially rematerializable and integrate it into TargetInstrInfo::isTriviallyReMaterializable. This way, all places that need to know whether an instruction is rematerializable will get the same answer. This enables the useful parts of the aggressive-remat option by default -- using AliasAnalysis to determine whether a memory location is invariant, and removes the questionable parts -- rematting operations with virtual register inputs that may not be live everywhere. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83687 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-09isTriviallyReMaterializable checks theDan Gohman
TargetInstrDesc::isRematerializable flag, so it isn't necessary to do this check in its callers. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83671 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-03Oops. Renamed remaining MachineInstrIndex references.Lang Hames
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83255 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-03Renamed MachineInstrIndex to LiveIndex.Lang Hames
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83254 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-28Coalescer should not delete extract_subreg, insert_subreg, and subreg_to_reg ofEvan Cheng
physical registers. This is especially critical for the later two since they start the live interval of a super-register. e.g. %DO<def> = INSERT_SUBREG %D0<undef>, %S0<kill>, 1 If this instruction is eliminated, the register scavenger will not be happy as D0 is not defined previously. This fixes PR5055. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82968 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-24Clean up LiveVariables and change how it deals with partial updates and ↵Evan Cheng
kills. This also eliminate the horrible check which scan forward to the end of the basic block. It should be faster and more accurate. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82676 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-23Fix a obvious logic error.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82610 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-22Fix a pasto. Also simplify for Bill's benefit.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82505 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-21Clean up spill weight computation. Also some changes to give loop inductionEvan Cheng
variable increment / decrement slighter high priority. This has major impact on some micro-benchmarks. On MultiSource/Applications and spec tests, it's a minor win. It also reduce 256.bzip instruction count by 8%, 55 on 164.gzip on i386 / Darwin. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82485 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-21Fix this assertion string to mention subreg_to_reg.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82455 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-20Tabs -> spaces, and remove trailing whitespace.Daniel Dunbar
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82355 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-17Fix PR4910: Broken logic in coalescer means when a physical register ↵Evan Cheng
liveness is being shortened, the sub-registers were not. The symptom is the register allocator could not find a free register for this particular test. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82108 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-12Remove -new-coalescer-heuristic. It's not useful.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81600 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-08When remat'ing and destination virtual register has a sub-register index. ↵Evan Cheng
Make sure the sub-register class matches the register class of the remat'ed instruction definition register class. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81204 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-04Replaces uses of unsigned for indexes in LiveInterval and VNInfo withLang Hames
a new class, MachineInstrIndex, which hides arithmetic details from most clients. This is a step towards allowing the register allocator to update/insert code during allocation. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81040 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23remove some uses of llvm/Support/Streams.hChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79842 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-23Change Pass::print to take a raw ostream instead of std::ostream,Chris Lattner
update all code that this affects. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79830 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-22Convert DOUT to DEBUG(errs()...).Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79765 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-10Modified VNInfo. The "copy" member is now a union which holds the copy for a ↵Lang Hames
register interval, or the defining register for a stack interval. Access is via getCopy/setCopy and getReg/setReg. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78620 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-07Another coalescer bug. When a dead copy is eliminated, transfer the kill to ↵Evan Cheng
a def of the exact register rather than a super-register. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78376 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-05Rename a variable to make MSVC happy.Benjamin Kramer
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78202 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-05Another nasty coalescer bug (is there another kind):Evan Cheng
After coalescing reg1027's def and kill are both at the same point: %reg1027,0.000000e+00 = [56,814:0) 0@70-(814) bb5: 60 %reg1027<def> = t2MOVr %reg1027, 14, %reg0, %reg0 68 %reg1027<def> = t2LDRi12 %reg1027<kill>, 8, 14, %reg0 76 t2CMPzri %reg1038<kill,undef>, 0, 14, %reg0, %CPSR<imp-def> 84 %reg1027<def> = t2MOVr %reg1027, 14, %reg0, %reg0 96 t2Bcc mbb<bb5,0x2030910>, 1, %CPSR<kill> Do not remove the kill marker on t2LDRi12. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78178 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-03Fix a coaelescer bug. If a copy val# is extended to eliminate a ↵Evan Cheng
non-trivially coalesced copy, and the copy kills its source register. Trim the source register's live range to the last use if possible. This fixes up kill marker to make the scavenger happy. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77967 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-31Use setPreservesAll and setPreservesCFG in CodeGen passes.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77754 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-29inline the global 'getInstrOperandRegClass' function into its callersChris Lattner
now that TargetOperandInfo does the heavy lifting. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77508 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-27Avoid build warnings.Mike Stump
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77271 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-25More migration to raw_ostream, the water has dried up around the iostream hole.Daniel Dunbar
- Some clients which used DOUT have moved to DEBUG. We are deprecating the "magic" DOUT behavior which avoided calling printing functions when the statement was disabled. In addition to being unnecessary magic, it had the downside of leaving code in -Asserts builds, and of hiding potentially unnecessary computations. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77019 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-22Make some changes suggested by Bill and Evan.David Greene
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76775 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-21Add some support for iterative coalescers to calculate a joined liveDavid Greene
range's weight properly. This is turned off right now in the sense that you'll get an assert if you get into a situation that can only be caused by an iterative coalescer. All other code paths operate exactly as before so there is no functional change with this patch. The asserts should be disabled if/when an iterative coalescer gets added to trunk. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76680 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-21Cross RC coalescing is now on by default.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76519 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-20Fix some sub-reg coalescing bugs where the coalescer wasn't updating the ↵Evan Cheng
resulting interval's register class. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76458 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-18Catch more coalescing opportunities.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76282 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-18Enable cross register class coalescing.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76281 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-17Simplify some more.Evan Cheng
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76239 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-17Simplify the coalescer (finally!) by making ↵Evan Cheng
LiveIntervals::processImplicitDefs a little more aggressive and teaching liveintervals to make use of isUndef marker on MachineOperands. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76223 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-16Let callers decide the sub-register index on the def operand of ↵Evan Cheng
rematerialized instructions. Avoid remat'ing instructions whose def have sub-register indices for now. It's just really really hard to get all the cases right. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75900 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-15ShortenDeadCopySrcLiveRange needs to be more conservative in multi-kill ↵Evan Cheng
situations. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75838 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-14llvm_unreachable->llvm_unreachable(0), LLVM_UNREACHABLE->llvm_unreachable.Torok Edwin
This adds location info for all llvm_unreachable calls (which is a macro now) in !NDEBUG builds. In NDEBUG builds location info and the message is off (it only prints "UREACHABLE executed"). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75640 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-14Fix pr4544. When remating, make sure the destination register fits the ↵Evan Cheng
instruction definition. It may be mismatched due to sub-register coalescing. No test case yet because the code doesn't trigger until 75408 is re-applied. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75572 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-11assert(0) -> LLVM_UNREACHABLE.Torok Edwin
Make llvm_unreachable take an optional string, thus moving the cerr<< out of line. LLVM_UNREACHABLE is now a simple wrapper that makes the message go away for NDEBUG builds. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75379 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-10Remove TargetInstrInfo::CommuteChangesDestination and added ↵Evan Cheng
findCommutedOpIndices which returns the operand indices which are swapped (when applicable). This allows for some code clean up and future enhancements. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75264 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-09Improved tracking of value number kills. VN kills are now representedLang Hames
as an (index,bool) pair. The bool flag records whether the kill is a PHI kill or not. This code will be used to enable splitting of live intervals containing PHI-kills. A slight change to live interval weights introduced an extra spill into lsr-code-insertion (outside the critical sections). The test condition has been updated to reflect this. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75097 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-01Remove special handling of implicit_def. Fix a couple more bugs in ↵Evan Cheng
liveintervalanalysis and coalescer handling of implicit_def. Note, isUndef marker must be placed even on implicit_def def operand or else the scavenger will not ignore it. This is necessary because -O0 path does not use liveintervalanalysis, it treats implicit_def just like any other def. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74601 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-22Fix another register coalescer crash: forgot to check if the instruction ↵Evan Cheng
being updated has already been coalesced. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73898 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-18- Update register allocation hint after coalescing. This is done by the ↵Evan Cheng
target since the hint is target dependent. This is important for ARM register pair hints. - Register allocator should resolve the second part of the hint (register number) before passing it to the target since it knows virtual register to physical register mapping. - More fixes to get ARM load / store double word working. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73671 91177308-0d34-0410-b5e6-96231b3b80d8