llvm-project/llvm/lib/CodeGen
Eli Friedman 23ae13d51f [ScheduleDAG] When a node is cloned, add an edge between the nodes.
InstrEmitter's virtual register handling assumes that clones are emitted
after the cloned node.  Make sure this assumption actually holds.

Fixes a "Node emitted out of order - early" assertion on the testcase.

This is probably a very rare case to actually hit in practice; even
without the explicit edge, the scheduler will usually end up scheduling
the nodes in the expected order due to other constraints.

Differential Revision: https://reviews.llvm.org/D68068

llvm-svn: 373782
2019-10-04 19:51:40 +00:00
..
AsmPrinter DebugInfo: Generalize rnglist emission as a precursor to reusing it for loclist emission 2019-10-03 20:56:23 +00:00
GlobalISel Revert "GlobalISel: Handle llvm.read_register" 2019-10-01 08:24:01 +00:00
MIRParser [Alignment][NFC] Remove unneeded llvm:: scoping on Align types 2019-09-27 12:54:21 +00:00
SelectionDAG [ScheduleDAG] When a node is cloned, add an edge between the nodes. 2019-10-04 19:51:40 +00:00
AggressiveAntiDepBreaker.cpp AggressiveAntiDepBreaker - silence static analyzer null dereference warning. NFCI. 2019-09-24 13:57:51 +00:00
AggressiveAntiDepBreaker.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
AllocationOrder.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
AllocationOrder.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
Analysis.cpp IR. Change strip* family of functions to not look through aliases. 2019-08-22 19:56:14 +00:00
AntiDepBreaker.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
AtomicExpandPass.cpp [Alignment][NFC] Remove StoreInst::setAlignment(unsigned) 2019-10-03 13:17:21 +00:00
BasicTargetTransformInfo.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
BranchFolding.cpp [NewPM] Port MachineModuleInfo to the new pass manager. 2019-09-30 17:54:50 +00:00
BranchFolding.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
BranchRelaxation.cpp [Alignment][NFC] Remove unneeded llvm:: scoping on Align types 2019-09-27 12:54:21 +00:00
BreakFalseDeps.cpp [BreakFalseDeps] ignore function with minsize attribute 2019-09-23 17:01:01 +00:00
BuiltinGCs.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
CFIInstrInserter.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
CMakeLists.txt [ModuloSchedule] Peel out prologs and epilogs, generate actual code 2019-10-02 12:46:44 +00:00
CalcSpillWeights.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
CallingConvLower.cpp [Alignment][NFC] Remove unneeded llvm:: scoping on Align types 2019-09-27 12:54:21 +00:00
CodeGen.cpp [NewPM] Port MachineModuleInfo to the new pass manager. 2019-09-30 17:54:50 +00:00
CodeGenPrepare.cpp [Alignment][NFC] Remove AllocaInst::setAlignment(unsigned) 2019-09-30 13:34:44 +00:00
CriticalAntiDepBreaker.cpp CriticalAntiDepBreaker - Assert that we've found the bottom of the critical path. NFCI. 2019-09-23 10:42:47 +00:00
CriticalAntiDepBreaker.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
DFAPacketizer.cpp [DFAPacketizer] Reapply: Track resources for packetized instructions 2019-09-09 13:17:55 +00:00
DeadMachineInstructionElim.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
DetectDeadLanes.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
DwarfEHPrepare.cpp Add an optional list of blocks to avoid when looking for a path in isPotentiallyReachable. 2019-04-02 01:05:48 +00:00
EarlyIfConversion.cpp [CodeGen] Add a pass to do block predication on SSA machine IR. 2019-08-20 15:54:59 +00:00
EdgeBundles.cpp Fix parameter name comments using clang-tidy. NFC. 2019-07-16 04:46:31 +00:00
ExecutionDomainFix.cpp Cleanup: llvm::bsearch -> llvm::partition_point after r364719 2019-06-30 11:19:56 +00:00
ExpandMemCmp.cpp Revert "Reland "r364412 [ExpandMemCmp][MergeICmps] Move passes out of CodeGen into opt pipeline."" 2019-09-10 10:39:09 +00:00
ExpandPostRAPseudos.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
ExpandReductions.cpp Change semantics of fadd/fmul vector reductions. 2019-06-11 08:22:10 +00:00
FEntryInserter.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
FaultMaps.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
FinalizeISel.cpp Rename ExpandISelPseudo->FinalizeISel, delay register reservation 2019-06-19 00:25:39 +00:00
FuncletLayout.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
GCMetadata.cpp [llvm] Migrate llvm::make_unique to std::make_unique 2019-08-15 15:54:37 +00:00
GCMetadataPrinter.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
GCRootLowering.cpp [NewPM] Port MachineModuleInfo to the new pass manager. 2019-09-30 17:54:50 +00:00
GCStrategy.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
GlobalMerge.cpp Use llvm::stable_sort 2019-04-23 14:51:27 +00:00
HardwareLoops.cpp Change TargetLibraryInfo analysis passes to always require Function 2019-09-07 03:09:36 +00:00
IfConversion.cpp [NewPM] Port MachineModuleInfo to the new pass manager. 2019-09-30 17:54:50 +00:00
ImplicitNullChecks.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
IndirectBrExpandPass.cpp Implementation of asm-goto support in LLVM 2019-02-08 20:48:56 +00:00
InlineSpiller.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
InterferenceCache.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
InterferenceCache.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
InterleavedAccessPass.cpp [InterleavedAccessPass] Don't increase the number of bytes loaded. 2019-03-28 20:44:50 +00:00
InterleavedLoadCombinePass.cpp InterleavedLoadCombine - merge isa<> and dyn_cast<> duplicates. NFCI. 2019-09-15 16:20:12 +00:00
IntrinsicLowering.cpp [opaque pointer types] Pass function types to CallInst creation. 2019-02-01 20:43:25 +00:00
LLVMBuild.txt Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
LLVMTargetMachine.cpp [NewPM] Port MachineModuleInfo to the new pass manager. 2019-09-30 17:54:50 +00:00
LatencyPriorityQueue.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
LazyMachineBlockFrequencyInfo.cpp [llvm] Migrate llvm::make_unique to std::make_unique 2019-08-15 15:54:37 +00:00
LexicalScopes.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
LiveDebugValues.cpp Fix MSVC "not all control paths return a value" warning. NFCI. 2019-10-04 12:45:27 +00:00
LiveDebugVariables.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
LiveDebugVariables.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
LiveInterval.cpp LiveIntervals: Remove assertion 2019-09-12 23:46:51 +00:00
LiveIntervalUnion.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
LiveIntervals.cpp Temporarily revert r371640 "LiveIntervals: Split live intervals on multiple dead defs". 2019-09-13 01:34:25 +00:00
LivePhysRegs.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
LiveRangeCalc.cpp Finish moving TargetRegisterInfo::isVirtualRegister() and friends to llvm::Register as started by r367614. NFC 2019-08-01 23:27:28 +00:00
LiveRangeCalc.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
LiveRangeEdit.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
LiveRangeShrink.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
LiveRangeUtils.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
LiveRegMatrix.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
LiveRegUnits.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
LiveStacks.cpp Finish moving TargetRegisterInfo::isVirtualRegister() and friends to llvm::Register as started by r367614. NFC 2019-08-01 23:27:28 +00:00
LiveVariables.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
LocalStackSlotAllocation.cpp [LLVM][Alignment] Introduce Alignment In MachineFrameInfo 2019-08-21 14:29:30 +00:00
LoopTraversal.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
LowLevelType.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
LowerEmuTLS.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
MIRCanonicalizerPass.cpp [mir-canon][NFC] Move MIR vreg renaming code to separate file for better reuse. 2019-09-04 21:29:10 +00:00
MIRNamerPass.cpp [MIR] MIRNamer pass for improving MIR test authoring experience. 2019-09-05 20:44:33 +00:00
MIRPrinter.cpp [Alignment][NFC] Remove unneeded llvm:: scoping on Align types 2019-09-27 12:54:21 +00:00
MIRPrintingPass.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
MIRVRegNamerUtils.cpp [mir-canon][NFC] Move MIR vreg renaming code to separate file for better reuse. 2019-09-04 21:29:10 +00:00
MIRVRegNamerUtils.h Hide implementation details in namespaces. 2019-09-17 12:56:29 +00:00
MachineBasicBlock.cpp [Alignment][NFC] Remove unneeded llvm:: scoping on Align types 2019-09-27 12:54:21 +00:00
MachineBlockFrequencyInfo.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
MachineBlockPlacement.cpp [NewPM] Port MachineModuleInfo to the new pass manager. 2019-09-30 17:54:50 +00:00
MachineBranchProbabilityInfo.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
MachineCSE.cpp [DebugInfo] LiveDebugValues: correctly discriminate kinds of variable locations 2019-09-02 12:28:36 +00:00
MachineCombiner.cpp Finish moving TargetRegisterInfo::isVirtualRegister() and friends to llvm::Register as started by r367614. NFC 2019-08-01 23:27:28 +00:00
MachineCopyPropagation.cpp Revert "[MachineCopyPropagation] Remove redundant copies after TailDup via machine-cp" 2019-09-09 16:46:45 +00:00
MachineDominanceFrontier.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
MachineDominators.cpp Reapply [Dominators][CodeGen] Clean up MachineDominators 2019-10-01 18:27:14 +00:00
MachineFrameInfo.cpp [Alignment][NFC] Remove unneeded llvm:: scoping on Align types 2019-09-27 12:54:21 +00:00
MachineFunction.cpp [Alignment][NFC] Remove unneeded llvm:: scoping on Align types 2019-09-27 12:54:21 +00:00
MachineFunctionPass.cpp [NewPM] Port MachineModuleInfo to the new pass manager. 2019-09-30 17:54:50 +00:00
MachineFunctionPrinterPass.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
MachineInstr.cpp Remove the AliasAnalysis argument in function areMemAccessesTriviallyDisjoint 2019-09-26 22:53:44 +00:00
MachineInstrBundle.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
MachineLICM.cpp [Dominators][CodeGen] Don't mark MachineDominatorTree as preserved in MachineLICM 2019-10-01 18:27:44 +00:00
MachineLoopInfo.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
MachineLoopUtils.cpp [ModuloSchedule] Peel out prologs and epilogs, generate actual code 2019-10-02 12:46:44 +00:00
MachineModuleInfo.cpp [NewPM] Port MachineModuleInfo to the new pass manager. 2019-09-30 17:54:50 +00:00
MachineModuleInfoImpls.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
MachineOperand.cpp [CodeGen] Remove unused MachineMemOperand::print wrappers (PR41772) 2019-10-02 16:20:28 +00:00
MachineOptimizationRemarkEmitter.cpp [llvm] Migrate llvm::make_unique to std::make_unique 2019-08-15 15:54:37 +00:00
MachineOutliner.cpp [NewPM] Port MachineModuleInfo to the new pass manager. 2019-09-30 17:54:50 +00:00
MachinePipeliner.cpp [ModuloSchedule] Peel out prologs and epilogs, generate actual code 2019-10-02 12:46:44 +00:00
MachinePostDominators.cpp [Dominators][CodeGen] Add MachinePostDominatorTree verification 2019-10-01 15:23:27 +00:00
MachineRegionInfo.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
MachineRegisterInfo.cpp Finish moving TargetRegisterInfo::isVirtualRegister() and friends to llvm::Register as started by r367614. NFC 2019-08-01 23:27:28 +00:00
MachineSSAUpdater.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
MachineScheduler.cpp [Dominators][CodeGen] Fix MachineDominatorTree preservation in PHIElimination 2019-10-01 18:27:17 +00:00
MachineSink.cpp [Dominators][CodeGen] Add MachinePostDominatorTree verification 2019-10-01 15:23:27 +00:00
MachineTraceMetrics.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
MachineVerifier.cpp Add an operand to memory intrinsics to denote the "tail" marker. 2019-09-28 05:33:21 +00:00
MacroFusion.cpp [llvm] Migrate llvm::make_unique to std::make_unique 2019-08-15 15:54:37 +00:00
ModuloSchedule.cpp [ModuloSchedule] Do not remap terminators 2019-10-04 17:15:25 +00:00
OptimizePHIs.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
PHIElimination.cpp [Dominators][CodeGen] Fix MachineDominatorTree preservation in PHIElimination 2019-10-01 18:27:17 +00:00
PHIEliminationUtils.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
PHIEliminationUtils.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
ParallelCG.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
PatchableFunction.cpp [Alignment][NFC] Remove unneeded llvm:: scoping on Align types 2019-09-27 12:54:21 +00:00
PeepholeOptimizer.cpp [AMDGPU] Prevent VGPR copies from moving across the EXEC mask definitions 2019-08-21 15:15:04 +00:00
PostRAHazardRecognizer.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
PostRASchedulerList.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
PreISelIntrinsicLowering.cpp lowerObjCCall - silence static analyzer dyn_cast<CallInst> null dereference warnings. NFCI. 2019-09-24 10:46:30 +00:00
ProcessImplicitDefs.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
PrologEpilogInserter.cpp [LLVM][Alignment] Introduce Alignment In MachineFrameInfo 2019-08-21 14:29:30 +00:00
PseudoSourceValue.cpp [llvm] Migrate llvm::make_unique to std::make_unique 2019-08-15 15:54:37 +00:00
README.txt Test commit: Removed trailing space in .txt file. 2018-12-06 13:20:27 +00:00
ReachingDefAnalysis.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
RegAllocBase.cpp Finish moving TargetRegisterInfo::isVirtualRegister() and friends to llvm::Register as started by r367614. NFC 2019-08-01 23:27:28 +00:00
RegAllocBase.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
RegAllocBasic.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
RegAllocFast.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
RegAllocGreedy.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
RegAllocPBQP.cpp [llvm] Migrate llvm::make_unique to std::make_unique 2019-08-15 15:54:37 +00:00
RegUsageInfoCollector.cpp Revert "[AArch64][DebugInfo] Do not recompute CalleeSavedStackSize" 2019-09-18 14:42:09 +00:00
RegUsageInfoPropagate.cpp [IPRA] Don't rely on non-exact function definitions 2019-07-19 09:59:26 +00:00
RegisterClassInfo.cpp [ARM] Thumb2: favor R4-R7 over R12/LR in allocation order when opt for minsize 2019-07-03 09:58:52 +00:00
RegisterCoalescer.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
RegisterCoalescer.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
RegisterPressure.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
RegisterScavenging.cpp RegScavenger: Use Register 2019-08-23 18:25:34 +00:00
RegisterUsageInfo.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
RenameIndependentSubregs.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
ResetMachineFunctionPass.cpp [ResetMachineFunctionPass] Add visited functions statistics info 2019-03-14 01:13:15 +00:00
SafeStack.cpp Change TargetLibraryInfo analysis passes to always require Function 2019-09-07 03:09:36 +00:00
SafeStackColoring.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
SafeStackColoring.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
SafeStackLayout.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
SafeStackLayout.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
ScalarizeMaskedMemIntrin.cpp [ScalarizeMaskedMemIntrin] Bitcast the mask to the scalar domain and use scalar bit tests for the branches for expandload/compressstore. 2019-08-02 23:43:53 +00:00
ScheduleDAG.cpp [ScheduleDAGRRList] Recompute topological ordering on demand. 2019-04-17 15:05:29 +00:00
ScheduleDAGInstrs.cpp MachineScheduler: Fix missing dependency with multiple subreg defs 2019-09-20 00:09:15 +00:00
ScheduleDAGPrinter.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
ScoreboardHazardRecognizer.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
ShadowStackGCLowering.cpp [opaque pointer types] Pass value type to LoadInst creation. 2019-02-01 20:44:24 +00:00
ShrinkWrap.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
SjLjEHPrepare.cpp Added address-space mangling for stack related intrinsics 2019-07-22 12:42:48 +00:00
SlotIndexes.cpp SlotIndexes: delete unused functions 2019-06-23 16:05:29 +00:00
SpillPlacement.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
SpillPlacement.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
Spiller.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
SplitKit.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
SplitKit.h Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
StackColoring.cpp Use llvm::stable_sort 2019-04-23 14:51:27 +00:00
StackMapLivenessAnalysis.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
StackMaps.cpp MCRegisterInfo: Merge getLLVMRegNum and getLLVMRegNumFromEH 2019-09-24 09:31:02 +00:00
StackProtector.cpp [SSP] [3/3] cmpxchg and addrspacecast instructions can now 2019-09-30 15:11:23 +00:00
StackSlotColoring.cpp Finish moving TargetRegisterInfo::isVirtualRegister() and friends to llvm::Register as started by r367614. NFC 2019-08-01 23:27:28 +00:00
SwiftErrorValueTracking.cpp GlobalISel: Remove unsigned variant of SrcOp 2019-06-24 16:16:12 +00:00
SwitchLoweringUtils.cpp Revert r372893 "[CodeGen] Replace -max-jump-table-size with -max-jump-table-targets" 2019-09-27 09:54:26 +00:00
TailDuplication.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
TailDuplicator.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
TargetFrameLoweringImpl.cpp Revert "[AArch64][DebugInfo] Do not recompute CalleeSavedStackSize" 2019-09-18 14:42:09 +00:00
TargetInstrInfo.cpp [DebugInfo] Exclude memory location values as parameter entry values 2019-09-27 13:52:43 +00:00
TargetLoweringBase.cpp Revert r372893 "[CodeGen] Replace -max-jump-table-size with -max-jump-table-targets" 2019-09-27 09:54:26 +00:00
TargetLoweringObjectFileImpl.cpp [Alignment][NFC] DataLayout migration to llvm::Align 2019-09-23 12:41:36 +00:00
TargetOptionsImpl.cpp Update the file headers across all of the LLVM projects in the monorepo 2019-01-19 08:50:56 +00:00
TargetPassConfig.cpp Revert "Reland "r364412 [ExpandMemCmp][MergeICmps] Move passes out of CodeGen into opt pipeline."" 2019-09-10 10:39:09 +00:00
TargetRegisterInfo.cpp [TargetRegisterInfo] Remove SVT argument from getCommonSubClass. 2019-09-13 05:24:37 +00:00
TargetSchedule.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
TargetSubtargetInfo.cpp [Subtarget] Merge ProcSched and ProcDesc arrays in MCSubtargetInfo into a single array. 2019-03-05 18:54:38 +00:00
TwoAddressInstructionPass.cpp Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM 2019-08-15 19:22:08 +00:00
UnreachableBlockElim.cpp [NewPM] Port MachineModuleInfo to the new pass manager. 2019-09-30 17:54:50 +00:00
ValueTypes.cpp [MVT] Add v256i1 to MachineValueType 2019-09-20 15:19:20 +00:00
VirtRegMap.cpp Eliminate implicit Register->unsigned conversions in VirtRegMap. NFC 2019-08-13 00:55:24 +00:00
WasmEHPrepare.cpp [WebAssembly] Make rethrow take an except_ref type argument 2019-03-16 05:38:57 +00:00
WinEHPrepare.cpp Fix parameter name comments using clang-tidy. NFC. 2019-07-16 04:46:31 +00:00
XRayInstrumentation.cpp [Backend] Keep call site info valid through the backend 2019-06-27 13:10:29 +00:00

README.txt

//===---------------------------------------------------------------------===//

Common register allocation / spilling problem:

        mul lr, r4, lr
        str lr, [sp, #+52]
        ldr lr, [r1, #+32]
        sxth r3, r3
        ldr r4, [sp, #+52]
        mla r4, r3, lr, r4

can be:

        mul lr, r4, lr
        mov r4, lr
        str lr, [sp, #+52]
        ldr lr, [r1, #+32]
        sxth r3, r3
        mla r4, r3, lr, r4

and then "merge" mul and mov:

        mul r4, r4, lr
        str r4, [sp, #+52]
        ldr lr, [r1, #+32]
        sxth r3, r3
        mla r4, r3, lr, r4

It also increase the likelihood the store may become dead.

//===---------------------------------------------------------------------===//

bb27 ...
        ...
        %reg1037 = ADDri %reg1039, 1
        %reg1038 = ADDrs %reg1032, %reg1039, %noreg, 10
    Successors according to CFG: 0x8b03bf0 (#5)

bb76 (0x8b03bf0, LLVM BB @0x8b032d0, ID#5):
    Predecessors according to CFG: 0x8b0c5f0 (#3) 0x8b0a7c0 (#4)
        %reg1039 = PHI %reg1070, mbb<bb76.outer,0x8b0c5f0>, %reg1037, mbb<bb27,0x8b0a7c0>

Note ADDri is not a two-address instruction. However, its result %reg1037 is an
operand of the PHI node in bb76 and its operand %reg1039 is the result of the
PHI node. We should treat it as a two-address code and make sure the ADDri is
scheduled after any node that reads %reg1039.

//===---------------------------------------------------------------------===//

Use local info (i.e. register scavenger) to assign it a free register to allow
reuse:
        ldr r3, [sp, #+4]
        add r3, r3, #3
        ldr r2, [sp, #+8]
        add r2, r2, #2
        ldr r1, [sp, #+4]  <==
        add r1, r1, #1
        ldr r0, [sp, #+4]
        add r0, r0, #2

//===---------------------------------------------------------------------===//

LLVM aggressively lift CSE out of loop. Sometimes this can be negative side-
effects:

R1 = X + 4
R2 = X + 7
R3 = X + 15

loop:
load [i + R1]
...
load [i + R2]
...
load [i + R3]

Suppose there is high register pressure, R1, R2, R3, can be spilled. We need
to implement proper re-materialization to handle this:

R1 = X + 4
R2 = X + 7
R3 = X + 15

loop:
R1 = X + 4  @ re-materialized
load [i + R1]
...
R2 = X + 7 @ re-materialized
load [i + R2]
...
R3 = X + 15 @ re-materialized
load [i + R3]

Furthermore, with re-association, we can enable sharing:

R1 = X + 4
R2 = X + 7
R3 = X + 15

loop:
T = i + X
load [T + 4]
...
load [T + 7]
...
load [T + 15]
//===---------------------------------------------------------------------===//

It's not always a good idea to choose rematerialization over spilling. If all
the load / store instructions would be folded then spilling is cheaper because
it won't require new live intervals / registers. See 2003-05-31-LongShifts for
an example.

//===---------------------------------------------------------------------===//

With a copying garbage collector, derived pointers must not be retained across
collector safe points; the collector could move the objects and invalidate the
derived pointer. This is bad enough in the first place, but safe points can
crop up unpredictably. Consider:

        %array = load { i32, [0 x %obj] }** %array_addr
        %nth_el = getelementptr { i32, [0 x %obj] }* %array, i32 0, i32 %n
        %old = load %obj** %nth_el
        %z = div i64 %x, %y
        store %obj* %new, %obj** %nth_el

If the i64 division is lowered to a libcall, then a safe point will (must)
appear for the call site. If a collection occurs, %array and %nth_el no longer
point into the correct object.

The fix for this is to copy address calculations so that dependent pointers
are never live across safe point boundaries. But the loads cannot be copied
like this if there was an intervening store, so may be hard to get right.

Only a concurrent mutator can trigger a collection at the libcall safe point.
So single-threaded programs do not have this requirement, even with a copying
collector. Still, LLVM optimizations would probably undo a front-end's careful
work.

//===---------------------------------------------------------------------===//

The ocaml frametable structure supports liveness information. It would be good
to support it.

//===---------------------------------------------------------------------===//

The FIXME in ComputeCommonTailLength in BranchFolding.cpp needs to be
revisited. The check is there to work around a misuse of directives in inline
assembly.

//===---------------------------------------------------------------------===//

It would be good to detect collector/target compatibility instead of silently
doing the wrong thing.

//===---------------------------------------------------------------------===//

It would be really nice to be able to write patterns in .td files for copies,
which would eliminate a bunch of explicit predicates on them (e.g. no side
effects).  Once this is in place, it would be even better to have tblgen
synthesize the various copy insertion/inspection methods in TargetInstrInfo.

//===---------------------------------------------------------------------===//

Stack coloring improvements:

1. Do proper LiveStacks analysis on all stack objects including those which are
   not spill slots.
2. Reorder objects to fill in gaps between objects.
   e.g. 4, 1, <gap>, 4, 1, 1, 1, <gap>, 4 => 4, 1, 1, 1, 1, 4, 4

//===---------------------------------------------------------------------===//

The scheduler should be able to sort nearby instructions by their address. For
example, in an expanded memset sequence it's not uncommon to see code like this:

  movl $0, 4(%rdi)
  movl $0, 8(%rdi)
  movl $0, 12(%rdi)
  movl $0, 0(%rdi)

Each of the stores is independent, and the scheduler is currently making an
arbitrary decision about the order.

//===---------------------------------------------------------------------===//

Another opportunitiy in this code is that the $0 could be moved to a register:

  movl $0, 4(%rdi)
  movl $0, 8(%rdi)
  movl $0, 12(%rdi)
  movl $0, 0(%rdi)

This would save substantial code size, especially for longer sequences like
this. It would be easy to have a rule telling isel to avoid matching MOV32mi
if the immediate has more than some fixed number of uses. It's more involved
to teach the register allocator how to do late folding to recover from
excessive register pressure.