llvm-6502/lib/CodeGen
Craig Topper dbd73669e5 Add missing semicolon from r222118.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222119 91177308-0d34-0410-b5e6-96231b3b80d8
2014-11-17 05:58:26 +00:00
..
AsmPrinter Rename EH related stuff to be more precise 2014-11-14 23:31:07 +00:00
SelectionDAG Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
AggressiveAntiDepBreaker.cpp Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
AggressiveAntiDepBreaker.h mop up: "Don’t duplicate function or class name at the beginning of the comment." 2014-09-21 14:48:16 +00:00
AllocationOrder.cpp [Modules] Remove potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:02:50 +00:00
AllocationOrder.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
Analysis.cpp Allow the use of functions as typeinfo in landingpad clauses 2014-11-14 00:35:50 +00:00
AntiDepBreaker.h mop up: "Don’t duplicate function or class name at the beginning of the comment." 2014-09-21 14:48:16 +00:00
AtomicExpandPass.cpp Lower idempotent RMWs to fence+load 2014-09-25 17:27:43 +00:00
BasicTargetTransformInfo.cpp Fix typo 2014-10-22 00:28:59 +00:00
BranchFolding.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
BranchFolding.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
CalcSpillWeights.cpp [PBQP] Tweak spill costs and coalescing benefits 2014-11-04 20:51:24 +00:00
CallingConvLower.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
CMakeLists.txt Add Forward Control-Flow Integrity. 2014-11-11 21:08:02 +00:00
CodeGen.cpp Rename AtomicExpandLoadLinked into AtomicExpand 2014-08-21 21:50:01 +00:00
CodeGenPrepare.cpp [CodeGenPrepare] Handle zero extensions in the TypePromotionHelper. 2014-11-13 01:44:51 +00:00
CriticalAntiDepBreaker.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
CriticalAntiDepBreaker.h mop up: "Don’t duplicate function or class name at the beginning of the comment." 2014-09-21 14:48:16 +00:00
DeadMachineInstructionElim.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
DFAPacketizer.cpp Remove the TargetMachine from DFAPacketizer since it was only 2014-10-14 01:03:16 +00:00
DwarfEHPrepare.cpp In DwarfEHPrepare, after all passes are run, RewindFunction may be a dangling 2014-09-14 20:36:28 +00:00
EarlyIfConversion.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
EdgeBundles.cpp Convert several loops over MachineFunction basic blocks to range-based loops 2014-04-30 18:29:51 +00:00
ErlangGC.cpp Have MachineFunction cache a pointer to the subtarget to make lookups 2014-08-05 02:39:49 +00:00
ExecutionDepsFix.cpp Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
ExpandISelPseudos.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
ExpandPostRAPseudos.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
ForwardControlFlowIntegrity.cpp Fix build break: remove unused variable in FCFI. 2014-11-11 21:26:33 +00:00
GCMetadata.cpp Use unique_ptr for the result of Registry entries. 2014-04-15 05:53:26 +00:00
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 Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
InlineSpiller.cpp Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
InterferenceCache.cpp [Modules] Remove potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:02:50 +00:00
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 Add Forward Control-Flow Integrity. 2014-11-11 21:08:02 +00:00
LatencyPriorityQueue.cpp [Modules] Remove potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:02:50 +00:00
LexicalScopes.cpp DebugInfo: Ensure that all debug location scope chains from instructions within a function, lead to the function itself. 2014-10-14 18:22:52 +00:00
LiveDebugVariables.cpp Added reset of LexicalScope in LiveDebugVariables reset function. 2014-10-24 02:46:50 +00:00
LiveDebugVariables.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
LiveInterval.cpp [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr. 2014-04-14 00:51:57 +00:00
LiveIntervalAnalysis.cpp Access the subtarget off of the MachineFunction rather than 2014-10-14 06:26:53 +00:00
LiveIntervalUnion.cpp [Modules] Remove potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:02:50 +00:00
LivePhysRegs.cpp
LiveRangeCalc.cpp [Modules] Remove potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:02:50 +00:00
LiveRangeCalc.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
LiveRangeEdit.cpp Add missing semicolon from r222118. 2014-11-17 05:58:26 +00:00
LiveRegMatrix.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
LiveStackAnalysis.cpp Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
LiveVariables.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
LLVMBuild.txt
LLVMTargetMachine.cpp Add Forward Control-Flow Integrity. 2014-11-11 21:08:02 +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 [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr. 2014-04-14 00:51:57 +00:00
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 Remove unused member variable. 2014-10-14 18:53:16 +00:00
MachineFunctionAnalysis.cpp Remove unused member variable. 2014-10-14 18:53:16 +00:00
MachineFunctionPass.cpp
MachineFunctionPrinterPass.cpp [C++11] Add 'override' keyword to virtual methods that override their base class. 2014-03-07 09:26:03 +00:00
MachineInstr.cpp Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
MachineInstrBundle.cpp Have MachineInstrBundle use the MachineFunction for subtarget 2014-10-14 06:26:55 +00:00
MachineLICM.cpp Remove the use and member variable of the TargetMachine from 2014-10-14 06:26:57 +00:00
MachineLoopInfo.cpp [C++11] Replace llvm::next and llvm::prior with std::next and std::prev. 2014-03-02 12:27:27 +00:00
MachineModuleInfo.cpp Allow the use of functions as typeinfo in landingpad clauses 2014-11-14 00:35:50 +00:00
MachineModuleInfoImpls.cpp
MachinePassRegistry.cpp [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr. 2014-04-14 00:51:57 +00:00
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 Access the subtarget off of the MachineFunction via the DAG 2014-10-14 06:56:25 +00:00
MachineSink.cpp [MachineSink] Use the real post dominator tree 2014-10-15 03:27:43 +00:00
MachineSSAUpdater.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
MachineTraceMetrics.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
MachineVerifier.cpp Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
Makefile
module.modulemap [modules] Add module maps for LLVM. These are not quite ready for prime-time 2014-05-21 02:46:14 +00:00
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 Rename EH related stuff to be more precise 2014-11-14 23:31:07 +00:00
PeepholeOptimizer.cpp Avoid caching the MachineFunction, we don't use it outside of 2014-10-15 21:06:25 +00:00
PHIElimination.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
PHIEliminationUtils.cpp Switch a number of loops in lib/CodeGen over to range-based for-loops, now that 2014-03-17 19:36:09 +00:00
PHIEliminationUtils.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
PostRASchedulerList.cpp Whitespace. 2014-10-29 15:23:11 +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 Grab the subtarget and subtarget dependent variables off of 2014-10-14 07:17:23 +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 Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
RegAllocBase.h Canonicalize header guards into a common format. 2014-08-13 16:26:38 +00:00
RegAllocBasic.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
RegAllocFast.cpp Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
RegAllocGreedy.cpp Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
RegAllocPBQP.cpp [PBQP] Callee saved regs should have a higher cost than scratch regs 2014-11-04 20:51:29 +00:00
RegisterClassInfo.cpp Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
RegisterCoalescer.cpp Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +00:00
RegisterCoalescer.h mop up: "Don’t duplicate function or class name at the beginning of the comment." 2014-09-20 22:39:16 +00:00
RegisterPressure.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
RegisterScavenging.cpp Grab the subtarget and subtarget dependent variables off of 2014-10-14 07:22:00 +00:00
ScheduleDAG.cpp Remove the TargetMachine forwards for TargetSubtargetInfo based 2014-08-04 21:25:23 +00:00
ScheduleDAGInstrs.cpp Remove an unnecessary restriction. MIsNeedChainEdge() should be checked even when scheduler AliasAnalysis is not 2014-09-12 21:17:55 +00:00
ScheduleDAGPrinter.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
ScoreboardHazardRecognizer.cpp Change MCSchedModel to be a struct of statically initialized data. 2014-09-02 17:43:54 +00:00
ShadowStackGC.cpp Use nullptr instead of NULL for variadic sentinels 2014-11-13 22:55:19 +00:00
SjLjEHPrepare.cpp Use nullptr instead of NULL for variadic sentinels 2014-11-13 22:55:19 +00:00
SlotIndexes.cpp [Modules] Remove potential ODR violations by sinking the DEBUG_TYPE 2014-04-22 02:02:50 +00:00
Spiller.h [RegAlloc] Kill off the trivial spiller - nobody is using it any more. 2014-11-06 19:12:38 +00:00
SpillPlacement.cpp Fix the threshold added in r186434 (a re-apply of r185393) and updaated 2014-10-02 22:23:14 +00:00
SpillPlacement.h Fix the threshold added in r186434 (a re-apply of r185393) and updaated 2014-10-02 22:23:14 +00:00
SplitKit.cpp Grab the subtarget and subtarget dependent variables off of 2014-10-14 07:22:00 +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 The patchpoint lowering logic would crash with live constants equal to 2014-11-04 00:59:21 +00:00
StackProtector.cpp Use nullptr instead of NULL for variadic sentinels 2014-11-13 22:55:19 +00:00
StackSlotColoring.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +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 Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
TargetInstrInfo.cpp Fix a lot of confusion around inserting nops on empty functions. 2014-09-15 18:32:58 +00:00
TargetLoweringBase.cpp Replace a couple asserts with static_asserts. 2014-11-17 00:26:50 +00:00
TargetLoweringObjectFileImpl.cpp Add three other sections when L symbols are allowed. 2014-11-06 05:01:21 +00:00
TargetOptionsImpl.cpp Add Forward Control-Flow Integrity. 2014-11-11 21:08:02 +00:00
TargetRegisterInfo.cpp Convert some EVTs to MVTs where only a SimpleValueType is needed. 2014-11-16 21:17:18 +00:00
TargetSchedule.cpp Remove unnecessary TargetMachine.h includes. 2014-10-14 07:22:08 +00:00
TwoAddressInstructionPass.cpp Improve logic that decides if its profitable to commute when some of the virtual registers involved have uses/defs chains connecting them to physical register. Fix up the tests that this change improves. 2014-11-05 06:43:02 +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 Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries. 2014-11-17 05:50:14 +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.