llvm-6502/lib/CodeGen
Juergen Ributzka 6042034603 [FastISel] Rename public visible FastISel functions. NFC.
This commit renames the following public FastISel functions:
LowerArguments -> lowerArguments
SelectInstruction -> selectInstruction
TargetSelectInstruction -> fastSelectInstruction
FastLowerArguments -> fastLowerArguments
FastLowerCall -> fastLowerCall
FastLowerIntrinsicCall -> fastLowerIntrinsicCall
FastEmitZExtFromI1 -> fastEmitZExtFromI1
FastEmitBranch -> fastEmitBranch
UpdateValueMap -> updateValueMap
TargetMaterializeConstant -> fastMaterializeConstant
TargetMaterializeAlloca -> fastMaterializeAlloca
TargetMaterializeFloatZero -> fastMaterializeFloatZero
LowerCallTo -> lowerCallTo

Reviewed by Eric

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217074 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-03 20:56:52 +00:00
..
AsmPrinter CodeGen: indicate Windows unwind data format 2014-09-01 23:48:39 +00:00
SelectionDAG [FastISel] Rename public visible FastISel functions. NFC. 2014-09-03 20:56:52 +00:00
AggressiveAntiDepBreaker.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
AggressiveAntiDepBreaker.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
AllocationOrder.cpp
AllocationOrder.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
Analysis.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
AntiDepBreaker.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
AtomicExpandPass.cpp Rename AtomicExpandLoadLinked into AtomicExpand 2014-08-21 21:50:01 +00:00
BasicTargetTransformInfo.cpp Reinstate "Nuke the old JIT." 2014-09-02 22:28:02 +00:00
BranchFolding.cpp [Branch probability] Recompute branch weights of tail-merged basic blocks. 2014-08-07 19:30:13 +00:00
BranchFolding.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
CalcSpillWeights.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
CallingConvLower.cpp Remove the target machine from CCState. Previously it was only used 2014-08-06 18:45:26 +00:00
CMakeLists.txt Reinstate "Nuke the old JIT." 2014-09-02 22:28:02 +00:00
CodeGen.cpp Rename AtomicExpandLoadLinked into AtomicExpand 2014-08-21 21:50:01 +00:00
CodeGenPrepare.cpp Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size. 2014-08-21 05:55:13 +00:00
CriticalAntiDepBreaker.cpp critical-anti-dependency breaker: don't use reg def info from kill insts (PR20308) 2014-08-20 18:03:00 +00:00
CriticalAntiDepBreaker.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
DeadMachineInstructionElim.cpp [Cleanup] Utility function to erase instruction and mark DBG_Values 2014-08-13 21:15:23 +00:00
DFAPacketizer.cpp Cleanup: Delete seemingly unused reference to MachineDominatorTree from ScheduleDAGInstrs. 2014-08-20 20:57:26 +00:00
DwarfEHPrepare.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
EarlyIfConversion.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
EdgeBundles.cpp
ErlangGC.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
ExecutionDepsFix.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
ExpandISelPseudos.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
ExpandPostRAPseudos.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
GCMetadata.cpp
GCMetadataPrinter.cpp
GCStrategy.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
GlobalMerge.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
IfConversion.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
InlineSpiller.cpp Fix in InlineSpiller to make the rematerilization loop also consider 2014-09-01 11:04:07 +00:00
InterferenceCache.cpp
InterferenceCache.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
IntrinsicLowering.cpp [PATCH][Interpreter] Add missing FP intrinsic lowering. 2014-08-30 18:33:35 +00:00
JumpInstrTables.cpp Don't manually (and forcibly) run the verifier on the entire module from 2014-07-30 05:44:04 +00:00
LatencyPriorityQueue.cpp
LexicalScopes.cpp Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size. 2014-08-21 05:55:13 +00:00
LiveDebugVariables.cpp test commit: remove trailing whitespace. 2014-08-07 20:04:00 +00:00
LiveDebugVariables.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
LiveInterval.cpp
LiveIntervalAnalysis.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
LiveIntervalUnion.cpp
LivePhysRegs.cpp
LiveRangeCalc.cpp
LiveRangeCalc.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
LiveRangeEdit.cpp Add TargetInstrInfo interface isAsCheapAsAMove. 2014-07-29 01:55:19 +00:00
LiveRegMatrix.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
LiveStackAnalysis.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
LiveVariables.cpp CodeGen/LiveVariables: use vector::assign() 2014-08-26 02:03:25 +00:00
LLVMBuild.txt
LLVMTargetMachine.cpp Reinstate "Nuke the old JIT." 2014-09-02 22:28:02 +00:00
LocalStackSlotAllocation.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
MachineBasicBlock.cpp [MachineDominatorTree] Provide a method to inform a MachineDominatorTree that a 2014-08-13 21:00:07 +00:00
MachineBlockFrequencyInfo.cpp Revert "Introduce a string_ostream string builder facilty" 2014-06-26 22:52:05 +00:00
MachineBlockPlacement.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
MachineBranchProbabilityInfo.cpp
MachineCodeEmitter.cpp
MachineCombiner.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
MachineCopyPropagation.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
MachineCSE.cpp In Machine CSE pass, the source register of a COPY machine instruction can 2014-08-11 05:17:19 +00:00
MachineDominanceFrontier.cpp Templatify DominanceFrontier. 2014-07-12 21:59:52 +00:00
MachineDominators.cpp [MachineDominatorTree] Provide a method to inform a MachineDominatorTree that a 2014-08-13 21:00:07 +00:00
MachineFunction.cpp Make isAliased property for fixed-offset stack objects adjustable 2014-08-16 00:17:02 +00:00
MachineFunctionAnalysis.cpp
MachineFunctionPass.cpp
MachineFunctionPrinterPass.cpp
MachineInstr.cpp [Cleanup] Utility function to erase instruction and mark DBG_Values 2014-08-13 21:15:23 +00:00
MachineInstrBundle.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
MachineLICM.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
MachineLoopInfo.cpp
MachineModuleInfo.cpp Delete dead code. NFC. 2014-08-15 14:58:22 +00:00
MachineModuleInfoImpls.cpp
MachinePassRegistry.cpp
MachinePostDominators.cpp
MachineRegionInfo.cpp Header hygiene: remove using directive and #undef DEBUG_TYPE once we're done. 2014-07-30 00:25:24 +00:00
MachineRegisterInfo.cpp CodeGen: switch raw array to std::vector 2014-08-25 00:28:31 +00:00
MachineScheduler.cpp Debugging Utility - optional ability for dumping critical path length 2014-08-07 21:49:44 +00:00
MachineSink.cpp [MachineSink] Use the real post dominator tree 2014-09-01 03:47:25 +00:00
MachineSSAUpdater.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
MachineTraceMetrics.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
MachineVerifier.cpp Modernize raw_fd_ostream's constructor a bit. 2014-08-25 18:16:47 +00:00
Makefile
module.modulemap
OcamlGC.cpp
OptimizePHIs.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
Passes.cpp Add pass-manager flags to use CFL AA 2014-09-02 22:12:54 +00:00
PeepholeOptimizer.cpp [PeepholeOptimizer] Enable the advanced copy optimization by default. 2014-08-21 22:23:52 +00:00
PHIElimination.cpp Use range based for loops to avoid needing to re-mention SmallPtrSet size. 2014-08-24 23:23:06 +00:00
PHIEliminationUtils.cpp
PHIEliminationUtils.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
PostRASchedulerList.cpp Cleanup: Delete seemingly unused reference to MachineDominatorTree from ScheduleDAGInstrs. 2014-08-20 20:57:26 +00:00
ProcessImplicitDefs.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
PrologEpilogInserter.cpp Use range based for loops to avoid needing to re-mention SmallPtrSet size. 2014-08-24 23:23:06 +00:00
PrologEpilogInserter.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
PseudoSourceValue.cpp Make isAliased property for fixed-offset stack objects adjustable 2014-08-16 00:17:02 +00:00
README.txt
RegAllocBase.cpp
RegAllocBase.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
RegAllocBasic.cpp Remove uses of the redundant ".reset(nullptr)" of unique_ptr, in favor of ".reset()" 2014-07-19 01:05:11 +00:00
RegAllocFast.cpp Use range based for loops to avoid needing to re-mention SmallPtrSet size. 2014-08-24 23:23:06 +00:00
RegAllocGreedy.cpp Simplify creation of a bunch of ArrayRefs by using None, makeArrayRef or just letting them be implicitly created. 2014-08-27 05:25:25 +00:00
RegAllocPBQP.cpp unique_ptrify PBQPBuilder::build 2014-09-02 17:42:01 +00:00
RegisterClassInfo.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
RegisterCoalescer.cpp Repace SmallPtrSet with SmallPtrSetImpl in function arguments to avoid needing to mention the size. 2014-08-21 05:55:13 +00:00
RegisterCoalescer.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
RegisterPressure.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
RegisterScavenging.cpp Changed the liveness tracking in the RegisterScavenger 2014-08-04 23:07:49 +00:00
ScheduleDAG.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
ScheduleDAGInstrs.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
ScheduleDAGPrinter.cpp
ScoreboardHazardRecognizer.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
ShadowStackGC.cpp
SjLjEHPrepare.cpp Use range based for loops to avoid needing to re-mention SmallPtrSet size. 2014-08-24 23:23:06 +00:00
SlotIndexes.cpp
Spiller.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
Spiller.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
SpillPlacement.cpp
SpillPlacement.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
SplitKit.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
SplitKit.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
StackColoring.cpp Fix typos in comments, NFC 2014-08-29 21:53:01 +00:00
StackMapLivenessAnalysis.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
StackMaps.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
StackProtector.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
StackSlotColoring.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
TailDuplication.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
TargetFrameLoweringImpl.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
TargetInstrInfo.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
TargetLoweringBase.cpp Reinstate "Nuke the old JIT." 2014-09-02 22:28:02 +00:00
TargetLoweringObjectFileImpl.cpp On MachO, don't put non-private constants in mergeable sections. 2014-08-28 20:13:31 +00:00
TargetOptionsImpl.cpp
TargetRegisterInfo.cpp
TargetSchedule.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
TwoAddressInstructionPass.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
UnreachableBlockElim.cpp Use range based for loops to avoid needing to re-mention SmallPtrSet size. 2014-08-24 23:23:06 +00:00
VirtRegMap.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00

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

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 LiveStackAnalysis 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.