summaryrefslogtreecommitdiffstats
path: root/llvm/lib/CodeGen/SplitKit.cpp
Commit message (Collapse)AuthorAgeFilesLines
* [WinEH] Update SplitAnalysis::computeLastSplitPoint to cope with multiple EH ↵David Majnemer2016-04-251-4/+12
| | | | | | | | | | | | | | | | | | | successors We didn't have logic to correctly handle CFGs where there was more than one EH-pad successor (these are novel with WinEH). There were situations where a register was live in one exceptional successor but not another but the code as written would only consider the first exceptional successor it found. This resulted in split points which were insufficiently early if an invoke was present. This fixes PR27501. N.B. This removes getLandingPadSuccessor. llvm-svn: 267412
* Recommit r265547, and r265610,r265639,r265657 on top of it, plusWei Mi2016-04-131-10/+102
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | two fixes with one about error verify-regalloc reported, and another about live range update of phi after rematerialization. r265547: Replace analyzeSiblingValues with new algorithm to fix its compile time issue. The patch is to solve PR17409 and its duplicates. analyzeSiblingValues is a N x N complexity algorithm where N is the number of siblings generated by reg splitting. Although it causes siginificant compile time issue when N is large, it is also important for performance since it removes redundent spills and enables rematerialization. To solve the compile time issue, the patch removes analyzeSiblingValues and replaces it with lower cost alternatives containing two parts. The first part creates a new spill hoisting method in postOptimization of register allocation. It does spill hoisting at once after all the spills are generated instead of inside every instance of selectOrSplit. The second part queries the define expr of the original register for rematerializaiton and keep it always available during register allocation even if it is already dead. It deletes those dead instructions only in postOptimization. With the two parts in the patch, it can remove analyzeSiblingValues without sacrificing performance. Patches on top of r265547: r265610 "Fix the compare-clang diff error introduced by r265547." r265639 "Fix the sanitizer bootstrap error in r265547." r265657 "InlineSpiller.cpp: Escap \@ in r265547. [-Wdocumentation]" Differential Revision: http://reviews.llvm.org/D15302 Differential Revision: http://reviews.llvm.org/D18934 Differential Revision: http://reviews.llvm.org/D18935 Differential Revision: http://reviews.llvm.org/D18936 llvm-svn: 266162
* Revert r265547 "Recommit r265309 after fixed an invalid memory reference bug ↵Hans Wennborg2016-04-081-87/+6
| | | | | | | | | | | | | happened" It caused PR27275: "ARM: Bad machine code: Using an undefined physical register" Also reverting the following commits that were landed on top: r265610 "Fix the compare-clang diff error introduced by r265547." r265639 "Fix the sanitizer bootstrap error in r265547." r265657 "InlineSpiller.cpp: Escap \@ in r265547. [-Wdocumentation]" llvm-svn: 265790
* Recommit r265309 after fixed an invalid memory reference bug happenedWei Mi2016-04-061-6/+87
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | when DenseMap growed and moved memory. I verified it fixed the bootstrap problem on x86_64-linux-gnu but I cannot verify whether it fixes the bootstrap error on clang-ppc64be-linux. I will watch the build-bot result closely. Replace analyzeSiblingValues with new algorithm to fix its compile time issue. The patch is to solve PR17409 and its duplicates. analyzeSiblingValues is a N x N complexity algorithm where N is the number of siblings generated by reg splitting. Although it causes siginificant compile time issue when N is large, it is also important for performance since it removes redundent spills and enables rematerialization. To solve the compile time issue, the patch removes analyzeSiblingValues and replaces it with lower cost alternatives containing two parts. The first part creates a new spill hoisting method in postOptimization of register allocation. It does spill hoisting at once after all the spills are generated instead of inside every instance of selectOrSplit. The second part queries the define expr of the original register for rematerializaiton and keep it always available during register allocation even if it is already dead. It deletes those dead instructions only in postOptimization. With the two parts in the patch, it can remove analyzeSiblingValues without sacrificing performance. Differential Revision: http://reviews.llvm.org/D15302 llvm-svn: 265547
* Revert r265309 and r265312 because they caused some errors I need to ↵Wei Mi2016-04-041-87/+6
| | | | | | investigate. llvm-svn: 265317
* Replace analyzeSiblingValues with new algorithm to fix its compileWei Mi2016-04-041-6/+87
| | | | | | | | | | | | | | | | | | | | | | | | | time issue. The patch is to solve PR17409 and its duplicates. analyzeSiblingValues is a N x N complexity algorithm where N is the number of siblings generated by reg splitting. Although it causes siginificant compile time issue when N is large, it is also important for performance since it removes redundent spills and enables rematerialization. To solve the compile time issue, the patch removes analyzeSiblingValues and replaces it with lower cost alternatives containing two parts. The first part creates a new spill hoisting method in postOptimization of register allocation. It does spill hoisting at once after all the spills are generated instead of inside every instance of selectOrSplit. The second part queries the define expr of the original register for rematerializaiton and keep it always available during register allocation even if it is already dead. It deletes those dead instructions only in postOptimization. With the two parts in the patch, it can remove analyzeSiblingValues without sacrificing performance. Differential Revision: http://reviews.llvm.org/D15302 llvm-svn: 265309
* CodeGen: Take MachineInstr& in SlotIndexes and LiveIntervals, NFCDuncan P. N. Exon Smith2016-02-271-8/+9
| | | | | | | | | | | | | | Take MachineInstr by reference instead of by pointer in SlotIndexes and the SlotIndex wrappers in LiveIntervals. The MachineInstrs here are never null, so this cleans up the API a bit. It also incidentally removes a few implicit conversions from MachineInstrBundleIterator to MachineInstr* (see PR26753). At a couple of call sites it was convenient to convert to a range-based for loop over MachineBasicBlock::instr_begin/instr_end, so I added MachineBasicBlock::instrs. llvm-svn: 262115
* Annotate dump() methods with LLVM_DUMP_METHOD, addressing Richard Smith ↵Yaron Keren2016-01-291-1/+1
| | | | | | | | r259192 post commit comment. clang part in r259232, this is the LLVM part of the patch. llvm-svn: 259240
* CodeGen: Remove implicit ilist iterator conversions, NFCDuncan P. N. Exon Smith2015-10-091-14/+16
| | | | | | | Finish removing implicit ilist iterator conversions from LLVMCodeGen. I'm sure there are lots more of these in lib/CodeGen/*/. llvm-svn: 249915
* LiveIntervalAnalysis: Factor common code into splitSeparateComponents; NFCMatthias Braun2015-09-221-10/+8
| | | | llvm-svn: 248241
* [WinEH] Add and use hasEHPadSuccessor instead of getLandingPadSuccessorReid Kleckner2015-09-171-0/+1
| | | | | | | | | | | | getLandingPadSuccessor assumes that each invoke can have at most one EH pad successor, but WinEH invokes can have more than one. Two out of three callers of getLandingPadSuccessor don't use the returned landingpad, so we can make them use this simple predicate instead. Eventually we'll have to circle back and fix SplitKit.cpp so that register allocation works. Baby steps. llvm-svn: 247904
* LiveIntervalAnalysis: Factor out code to update liveness on vreg def removalMatthias Braun2015-01-211-6/+4
| | | | | | | | | | | This cleans up code and is more in line with the general philosophy of modifying LiveIntervals through LiveIntervalAnalysis instead of changing them directly. This also fixes a case where SplitEditor::removeBackCopies() would miss the subregister ranges. llvm-svn: 226690
* LiveInterval: Use more range based for loops for value numbers and segments.Matthias Braun2014-12-101-27/+16
| | | | llvm-svn: 223978
* Grab the subtarget and subtarget dependent variables off ofEric Christopher2014-10-141-8/+2
| | | | | | MachineFunction rather than TargetMachine. llvm-svn: 219671
* Have MachineFunction cache a pointer to the subtarget to make lookupsEric Christopher2014-08-051-1/+1
| | | | | | | | | | | shorter/easier and have the DAG use that to do the same lookup. This can be used in the future for TargetMachine based caching lookups from the MachineFunction easily. Update the MIPS subtarget switching machinery to update this pointer at the same time it runs. llvm-svn: 214838
* Remove the TargetMachine forwards for TargetSubtargetInfo basedEric Christopher2014-08-041-23/+16
| | | | | | information and update all callers. No functional change. llvm-svn: 214781
* [Modules] Remove potential ODR violations by sinking the DEBUG_TYPEChandler Carruth2014-04-221-1/+2
| | | | | | | | | | | | define below all header includes in the lib/CodeGen/... tree. While the current modules implementation doesn't check for this kind of ODR violation yet, it is likely to grow support for it in the future. It also removes one layer of macro pollution across all the included headers. Other sub-trees will follow. llvm-svn: 206837
* [C++11] More 'nullptr' conversion. In some cases just using a boolean check ↵Craig Topper2014-04-141-7/+7
| | | | | | instead of comparing to nullptr. llvm-svn: 206142
* Switch a number of loops in lib/CodeGen over to range-based for-loops, now thatOwen Anderson2014-03-171-5/+3
| | | | | | the MachineRegisterInfo iterators are compatible with it. llvm-svn: 204075
* Phase 2 of the great MachineRegisterInfo cleanup. This time, we're changingOwen Anderson2014-03-131-3/+3
| | | | | | | | | | operator* on the by-operand iterators to return a MachineOperand& rather than a MachineInstr&. At this point they almost behave like normal iterators! Again, this requires making some existing loops more verbose, but should pave the way for the big range-based for-loop cleanups in the future. llvm-svn: 203865
* [C++11] Replace llvm::tie with std::tie.Benjamin Kramer2014-03-021-5/+5
| | | | | | The old implementation is no longer needed in C++11. llvm-svn: 202644
* [C++11] Replace llvm::next and llvm::prior with std::next and std::prev.Benjamin Kramer2014-03-021-2/+2
| | | | | | Remove the old functions. llvm-svn: 202636
* Work on LiveRange instead of LiveInterval where possibleMatthias Braun2013-10-101-9/+9
| | | | | | | Also change some pointer arguments to references at some places where 0-pointers are not allowed. llvm-svn: 192396
* Rename LiveRange to LiveInterval::SegmentMatthias Braun2013-10-101-7/+7
| | | | | | | | The Segment struct contains a single interval; multiple instances of this struct are used to construct a live range, but the struct is not a live range by itself. llvm-svn: 192392
* Auto-compute live intervals on demand.Mark Lacey2013-08-141-3/+3
| | | | | | | | | | | | | | | When new virtual registers are created during splitting/spilling, defer creation of the live interval until we need to use the live interval. Along with the recent commits to notify LiveRangeEdit when new virtual registers are created, this makes it possible for functions like TargetInstrInfo::loadRegFromStackSlot() and TargetInstrInfo::storeRegToStackSlot() to create multiple virtual registers as part of the process of generating loads/stores for different register classes, and then have the live intervals for those new registers computed when they are needed. llvm-svn: 188437
* Track new virtual registers by register number.Mark Lacey2013-08-141-12/+15
| | | | | | | | | | Track new virtual registers by register number, rather than by the live interval created for them. This is the first step in separating the creation of new virtual registers and new live intervals. Eventually live intervals will be created and populated on demand after the virtual registers have been created and used in instructions. llvm-svn: 188434
* Remove unnecessary parameter to RenumberValues.Jakob Stoklund Olesen2013-08-141-1/+1
| | | | | | Patch by Matthias Braun! llvm-svn: 188393
* Switch spill weights from a basic loop depth estimation to BlockFrequencyInfo.Benjamin Kramer2013-06-171-2/+4
| | | | | | | | | | | | | | | | | | The main advantages here are way better heuristics, taking into account not just loop depth but also __builtin_expect and other static heuristics and will eventually learn how to use profile info. Most of the work in this patch is pushing the MachineBlockFrequencyInfo analysis into the right places. This is good for a 5% speedup on zlib's deflate (x86_64), there were some very unfortunate spilling decisions in its hottest loop in longest_match(). Other benchmarks I tried were mostly neutral. This changes register allocation in subtle ways, update the tests for it. 2012-02-20-MachineCPBug.ll was deleted as it's very fragile and the instruction it looked for was gone already (but the FileCheck pattern picked up unrelated stuff). llvm-svn: 184105
* Make the LiveRegMatrix analysis available to targets.Jakob Stoklund Olesen2012-11-281-1/+1
| | | | | | | | | | | No functional change, just moved header files. Targets can inject custom passes between register allocation and rewriting. This makes it possible to tweak the register allocation before rewriting, using the full global interference checking available from LiveRegMatrix. llvm-svn: 168806
* Release build: guard dump functions withManman Ren2012-09-111-1/+1
| | | | | | | | "#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)" No functional change. Update r163339. llvm-svn: 163653
* Release build: guard dump functions with "ifndef NDEBUG"Manman Ren2012-09-061-0/+2
| | | | | | No functional change. llvm-svn: 163339
* Fix a couple of loops that were processing unused value numbers.Jakob Stoklund Olesen2012-08-031-1/+5
| | | | | | | Unused VNInfos should be left alone. Their def SlotIndex doesn't point to anything. llvm-svn: 161257
* Eliminate the IS_PHI_DEF flag and VNInfo::setIsPHIDef().Jakob Stoklund Olesen2012-07-271-2/+1
| | | | | | | | A value number is a PHI def if and only if it begins at a block boundary. This can be derived from the def slot, a separate flag is not necessary. llvm-svn: 160893
* Pass context pointers to LiveRangeCalc::reset().Jakob Stoklund Olesen2012-06-041-10/+8
| | | | | | | Remove the same pointers from all the other LiveRangeCalc functions, simplifying the interface. llvm-svn: 157941
* Moved LiveRangeEdit.h so that it can be called from other parts of the ↵Pete Cooper2012-04-021-1/+1
| | | | | | backend, not just libCodeGen llvm-svn: 153906
* Refactored the LiveRangeEdit interface so that MachineFunction, ↵Pete Cooper2012-04-021-8/+8
| | | | | | TargetInstrInfo, MachineRegisterInfo, LiveIntervals, and VirtRegMap are all passed into the constructor and stored as members instead of passed in to each method. llvm-svn: 153903
* Don't store COPY pointers in VNInfo.Jakob Stoklund Olesen2012-02-041-5/+2
| | | | | | | | | | If a value is defined by a COPY, that instuction can easily and cheaply be found by getInstructionFromIndex(VNI->def). This reduces the size of VNInfo from 24 to 16 bytes, and improves llc compile time by 3%. llvm-svn: 149763
* More dead code removal (using -Wunreachable-code)David Blaikie2012-01-201-1/+0
| | | | llvm-svn: 148578
* Detect when a value is undefined on an edge to a landing pad.Jakob Stoklund Olesen2012-01-111-4/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Consider this code: int h() { int x; try { x = f(); g(); } catch (...) { return x+1; } return x; } The variable x is undefined on the first edge to the landing pad, but it has the f() return value on the second edge to the landing pad. SplitAnalysis::getLastSplitPoint() would assume that the return value from f() was live into the landing pad when f() throws, which is of course impossible. Detect these cases, and treat them as if the landing pad wasn't there. This allows spill code to be inserted after the function call to f(). <rdar://problem/10664933> llvm-svn: 147912
* Exclusively use SplitAnalysis::getLastSplitPoint().Jakob Stoklund Olesen2012-01-111-2/+10
| | | | | | | | | Delete the alternative implementation in LiveIntervalAnalysis. These functions computed the same thing, but SplitAnalysis caches the result. llvm-svn: 147911
* Add bundle aware API for querying instruction properties and switch the codeEvan Cheng2011-12-071-1/+1
| | | | | | | | | | | | | | generator to it. For non-bundle instructions, these behave exactly the same as the MC layer API. For properties like mayLoad / mayStore, look into the bundle and if any of the bundled instructions has the property it would return true. For properties like isPredicable, only return true if *all* of the bundled instructions have the property. For properties like canFoldAsLoad, isCompare, conservatively return false for bundles. llvm-svn: 146026
* Use getVNInfoBefore() when it makes sense.Jakob Stoklund Olesen2011-11-141-1/+1
| | | | llvm-svn: 144517
* Terminate all dead defs at the dead slot instead of the 'next' slot.Jakob Stoklund Olesen2011-11-131-5/+5
| | | | | | | | | | | | | | | | | | | This makes no difference for normal defs, but early clobber dead defs now look like: [Slot_EarlyClobber; Slot_Dead) instead of: [Slot_EarlyClobber; Slot_Register). Live ranges for normal dead defs look like: [Slot_Register; Slot_Dead) as before. llvm-svn: 144512
* Rename SlotIndexes to match how they are used.Jakob Stoklund Olesen2011-11-131-5/+5
| | | | | | | | | | | | | | | | | | | | The old naming scheme (load/use/def/store) can be traced back to an old linear scan article, but the names don't match how slots are actually used. The load and store slots are not needed after the deferred spill code insertion framework was deleted. The use and def slots don't make any sense because we are using half-open intervals as is customary in C code, but the names suggest closed intervals. In reality, these slots were used to distinguish early-clobber defs from normal defs. The new naming scheme also has 4 slots, but the names match how the slots are really used. This is a purely mechanical renaming, but some of the code makes a lot more sense now. llvm-svn: 144503
* Spill mode: Hoist back-copies locally.Jakob Stoklund Olesen2011-09-161-6/+17
| | | | | | | | | | | | | | | | | The leaveIntvAfter() function normally inserts a back-copy after the requested instruction, making the back-copy kill the live range. In spill mode, try to insert the back-copy before the last use instead. That means the last use becomes the kill instead of the back-copy. This lowers the register pressure because the last use can now redefine the same register it was reading. This will also improve compile time: The back-copy isn't a kill, so hoisting it in hoistCopiesForSize() won't force a recomputation of the source live range. Similarly, if the back-copy isn't hoisted by the splitter, the spiller will not attempt hoisting it locally. llvm-svn: 139883
* Hoist back-copies to the least busy dominator.Jakob Stoklund Olesen2011-09-141-2/+61
| | | | | | | | | | | | | | | | When a back-copy is hoisted to the nearest common dominator, keep looking up the dominator tree for a less loopy dominator, and place the back-copy there instead. Don't do this when a single existing back-copy dominates all the others. Assume the client knows what he is doing, and keep the dominating back-copy. This prevents us from hoisting back-copies into loops in most cases. If a value is defined in a loop with multiple exits, we may still hoist back-copies into that loop. That is the speed/size tradeoff. llvm-svn: 139698
* Distinguish complex mapped values from forced recomputation.Jakob Stoklund Olesen2011-09-131-31/+26
| | | | | | | | | | | | | | | | | | When a ParentVNI maps to multiple defs in a new interval, its live range may still be derived directly from RegAssign by transferValues(). On the other hand, when instructions have been rematerialized or hoisted, it may be necessary to completely recompute live ranges using LiveRangeCalc::extend() to all uses. Use a bit in the value map to indicate that a live range must be recomputed. Rename markComplexMapped() to forceRecompute(). This fixes some live range verification errors when -split-spill-mode=size hoists back-copies by recomputing source ranges when RegAssign kills can't be moved. llvm-svn: 139660
* Implement -split-spill-mode=size.Jakob Stoklund Olesen2011-09-131-0/+156
| | | | | | | | | | Whenever the complement interval is defined by multiple copies of the same value, hoist those back-copies to the nearest common dominator. This ensures that at most one copy is inserted per value in the complement inteval, and no phi-defs are needed. llvm-svn: 139651
* Add SplitEditor::markOverlappedComplement().Jakob Stoklund Olesen2011-09-131-2/+13
| | | | | | | | This function is used to flag values where the complement interval may overlap other intervals. Call it from overlapIntv, and use the flag to fully recompute those live ranges in transferValues(). llvm-svn: 139612
* Eliminate the extendRange() wrapper.Jakob Stoklund Olesen2011-09-131-16/+15
| | | | llvm-svn: 139608
OpenPOWER on IntegriCloud