Commit Graph

20655 Commits

Author SHA1 Message Date
Sanjay Patel c91351c2b7 clean up; NFCI
llvm-svn: 268564
2016-05-04 22:39:36 +00:00
Simon Pilgrim 1f5ad702f8 [SelectionDAG] BITREVERSE vector legalization of bit operations (REAPPLIED)
Some vector bit operations are promoted instead of having custom lowering. This patch changes the isOperationLegalOrCustom tests for vector AND/OR operations to use a new TLI helper isOperationLegalOrCustomOrPromote instead, allowing the SSE implementations to stay on the simd unit.

Differential Revision: http://reviews.llvm.org/D19805

llvm-svn: 268561
2016-05-04 22:08:51 +00:00
Eric Christopher 75d661a280 Spelling and grammar corrections in comments.
llvm-svn: 268560
2016-05-04 21:45:36 +00:00
Simon Pilgrim 1a14f0d25c Revert r268504
llvm-svn: 268526
2016-05-04 17:49:14 +00:00
Simon Pilgrim b97c06210b [SelectionDAG] BITREVERSE vector legalization of bit operations
Vector bit operations are typically promoted instead of having custom lowering. This patch changes the isOperationLegalOrCustom tests for vector AND/OR operations to use isOperationLegalOrPromote instead, allowing the SSE implementations to stay on the simd unit.

Differential Revision: http://reviews.llvm.org/D19805

llvm-svn: 268504
2016-05-04 15:01:13 +00:00
Andrew Kaylor 50271f787e Add opt-bisect support to additional passes that can be skipped
Differential Revision: http://reviews.llvm.org/D19882

llvm-svn: 268457
2016-05-03 22:32:30 +00:00
Quentin Colombet 26dab3a485 [ImplicitNullChecks] Account for implicit-defs as well when updating the liveness.
The replaced load may have implicit-defs and those defs may be used
in the block of the original load. Make sure to update the liveness
accordingly.

This is a generalization of r267817.

llvm-svn: 268412
2016-05-03 18:09:06 +00:00
Craig Topper 3fc0e668ff [CodeGen] Add some space optimized forms of EmitNode and MorphNodeTo that implicitly indicate the number of result VTs. This shaves about 16K off the X86 matching table taking it down to about 470K.
Overall this reduces the llc binary size with all in-tree targets by about 40K.

llvm-svn: 268365
2016-05-03 05:54:13 +00:00
Matthias Braun d1aabb2813 livePhysRegs: Pass MBB by reference in addLive{Ins|Outs}(); NFC
The block must no be nullptr for the addLiveIns()/addLiveOuts()
function.

llvm-svn: 268340
2016-05-03 00:24:32 +00:00
Matthias Braun 24f26e6d91 LivePhysRegs: Automatically determine presence of pristine regs.
Remove the AddPristinesAndCSRs parameters from
addLiveIns()/addLiveOuts().

We need to respect pristine registers after prologue epilogue insertion,
Seeing that we got this wrong in at least two commits already, we should
rather pay the small price to query MachineFrameInfo for it.

There are three cases that did not set AddPristineAndCSRs to true even
after register allocation:
- ExecutionDepsFix: live-out registers are used as a hint that the
  register is used soon. This is not true for pristine registers so
  use the new addLiveOutsNoPristines() to maintain this behaviour.
- SystemZShortenInst: Not setting AddPristineAndCSRs to true looks like
  a bug, should do the right thing automatically now.
- StackMapLivenessAnalysis: Not adding pristine registers looks like a
  bug to me. Added a FIXME comment but maintain the current behaviour
  as a change may need to get coordinated with GC runtimes.

llvm-svn: 268336
2016-05-03 00:08:46 +00:00
Reid Kleckner 97837b7b09 [MC] Create unique .pdata sections for every .text section
Summary:
This adds a unique ID to the COFF section uniquing map, similar to the
one we have for ELF.  The unique id is not currently exposed via the
assembler because we don't have a use case for it yet. Users generally
create .pdata with the .seh_* family of directives, and the assembler
internally needs to produce .pdata and .xdata sections corresponding to
the code section.

The association between .text sections and the assembler-created .xdata
and .pdata sections is maintained as an ID field of MCSectionCOFF. The
CFI-related sections are created with the given unique ID, so if more
code is added to the same text section, we can find and reuse the CFI
sections that were already created.

Reviewers: majnemer, rafael

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D19376

llvm-svn: 268331
2016-05-02 23:22:18 +00:00
Quentin Colombet 776e6de516 [MachineBlockPlacement] Let the target optimize the branches at the end.
After the layout of the basic blocks is set, the target may be able to get rid
of unconditional branches to fallthrough blocks that the generic code does not
catch. This happens any time TargetInstrInfo::AnalyzeBranch is not able to
analyze all the branches involved in the terminators sequence, while still
understanding a few of them.

In such situation, AnalyzeBranch can directly modify the branches if it has been
instructed to do so.

This patch takes advantage of that.

llvm-svn: 268328
2016-05-02 22:58:59 +00:00
Quentin Colombet 4e1d389ac5 [X86] Model FAULTING_LOAD_OP as a terminator and branch.
This operation may branch to the handler block and we do not want it
to happen anywhere within the basic block.
Moreover, by marking it "terminator and branch" the machine verifier
does not wrongly assume (because of AnalyzeBranch not knowing better)
the branch is analyzable. Indeed, the target was seeing only the
unconditional branch and not the faulting load op and thought it was
a simple unconditional block.
The machine verifier was complaining because of that and moreover,
other optimizations could have done wrong transformation!

In the process, simplify the representation of the handler block in
the faulting load op. Now, we directly reference the handler block
instead of using a label. This has the benefits of:
1. MC knows how to issue a label for a BB, so leave that to it.
2. Accessing the target BB from its label is painful, whereas it is
   direct from a MBB operand.

Note: The 2 bytes offset in implicit-null-check.ll comes from the
fact the unconditional jumps are not removed anymore, as the whole
terminator sequence is not analyzable anymore.

Will fix it in a subsequence commit.

llvm-svn: 268327
2016-05-02 22:58:54 +00:00
Wolfgang Pieb 56aa4b0629 DebugInfo: Avoid propagating incorrect debug locations in SelectionDAG via CSE.
Summary:
When SelectionDAG performs CSE it is possible that the context's source
location is different from that of the selected node. This can lead to
incorrect line number records. We update the debug location to the
one that occurs earlier in the instruction sequence.

This fixes PR21006.

Reviewers: echristo, sdmitrouk

Subscribers: jevinskie, asl, llvm-commits

Differential Revision: http://reviews.llvm.org/D12094

llvm-svn: 268323
2016-05-02 22:50:51 +00:00
NAKAMURA Takumi bc46f624cd ScheduleDAGInstrs.cpp: Don't peel the iterator when it points the end. This will fix the crash in r268143.
llvm-svn: 268257
2016-05-02 17:29:55 +00:00
Chad Rosier a306eeb252 Cleanup comments. NFC.
llvm-svn: 268233
2016-05-02 14:32:17 +00:00
Eric Christopher 94a9ee65c6 Fix grammar and correct comment - the debug information wasn't incorrect, rather suboptimal.
llvm-svn: 268211
2016-05-02 05:30:26 +00:00
Craig Topper e3c1e225d7 [CodeGen] Add OPC_MoveChild0-OPC_MoveChild7 opcodes to isel matching tables to optimize table size. Shaves about 12K off the X86 matcher table.
llvm-svn: 268209
2016-05-02 01:53:30 +00:00
Igor Breger 110af565c7 getelementptr instruction, support index vector of EVT.
Differential Revision: http://reviews.llvm.org/D19775

llvm-svn: 268195
2016-05-01 13:29:12 +00:00
Saleem Abdulrasool e0f0c0e247 CodeGen: convert to range based loops
Convert to using some range based loops, avoid unnecessary variables for
unchecked casts.  NFC.

llvm-svn: 268165
2016-04-30 18:15:34 +00:00
Amjad Aboud 72da9391f0 Reverting 268054 & 268063 as they caused PR27579.
llvm-svn: 268150
2016-04-30 01:44:07 +00:00
Haicheng Wu 4afe0425db [MBP] Use Function::optForSize() instead of checking OptimizeForSize directly.
Fix a FIXME.  Disable loop alignment if compiled with -Oz now.

llvm-svn: 268121
2016-04-29 22:01:10 +00:00
Matt Arsenault ab2232cf73 DAGCombiner: Reduce truncated shl width
llvm-svn: 268094
2016-04-29 19:53:16 +00:00
Simon Pilgrim 464f1f3bea Use SelectionDAG::getTargetConstant* helper functions. NFC.
Instead of SelectionDAG::getConstant directly to make it more obvious that we're creating target constants.

llvm-svn: 268074
2016-04-29 17:42:45 +00:00
Haicheng Wu e749ce53d4 [MBP] Split placement and alignment into two functions. NFC.
Cut and Paste.

llvm-svn: 268067
2016-04-29 17:06:44 +00:00
Amjad Aboud 293ee8bba1 Recommitted r264280 "Supporting all entities declared in lexical scope in LLVM debug info."
After fixing PR26942 in r267004.

llvm-svn: 268054
2016-04-29 16:07:55 +00:00
Filipe Cabecinhas 0da9937517 Unify XDEBUG and EXPENSIVE_CHECKS (into the latter), and add an option to the cmake build to enable them.
Summary:
Historically, we had a switch in the Makefiles for turning on "expensive
checks". This has never been ported to the cmake build, but the
(dead-ish) code is still around.

This will also make it easier to turn it on in buildbots.

Reviewers: chandlerc

Subscribers: jyknight, mzolotukhin, RKSimon, gberry, llvm-commits

Differential Revision: http://reviews.llvm.org/D19723

llvm-svn: 268050
2016-04-29 15:22:48 +00:00
Matthias Braun f3619b8212 RegisterPressure: Fix default lanemask for missing regunit intervals
In case of missing live intervals for a physical registers
getLanesWithProperty() would report 0 which was not a safe default in
all situations. Add a parameter to pass in a safe default.
No testcase because in-tree targets do not skip computing register unit
live intervals.

Also cleanup the getXXX() functions to not perform the
RequireLiveIntervals checks anymore so we do not even need to return
safe defaults.

llvm-svn: 267977
2016-04-29 02:44:54 +00:00
Matthias Braun 5e4ac856d6 RegisterPressure: Cannot produce dead (subregister) defs anymore
With the DetectDeadLanes pass in place we cannot run into situations
anymore where defs suddenly become dead.
Also add a missing check so we do not try to add an undef flag to a
physreg (found by visual inspection, no failing test).

llvm-svn: 267976
2016-04-29 02:44:48 +00:00
Matthias Braun f84547c6e0 LiveIntervalAnalysis: Remove LiveVariables requirement
This requirement was a huge hack to keep LiveVariables alive because it
was optionally used by TwoAddressInstructionPass and PHIElimination.
However we have AnalysisUsage::addUsedIfAvailable() which we can use in
those passes.

This re-applies r260806 with LiveVariables manually added to PowerPC to
hopefully not break the stage 2 bots this time.

llvm-svn: 267954
2016-04-28 23:42:51 +00:00
Marcin Koscielnicki 3a592df3e4 [CodeGen] Remove extra ';'
Squashes a -Wpedantic warning.

llvm-svn: 267944
2016-04-28 21:49:46 +00:00
Matthias Braun e9631f166e LiveIntervalAnalysis: No need to deal with dead subregister defs anymore.
The DetectDeadLaneMask already ensures that we have no dead subregister
definitions making the special handling in LiveIntervalAnalysis
unnecessary. This reverts most of r248335.

llvm-svn: 267937
2016-04-28 20:35:26 +00:00
Krzysztof Parzyszek 7ea9a529aa Reset the TopRPTracker's position in ScheduleDAGMILive::initQueues
ScheduleDAGMI::initQueues changes the RegionBegin to the first non-debug
instruction. Since it does not track register pressure, it does not affect
any RP trackers. ScheduleDAGMILive inherits initQueues from ScheduleDAGMI,
and it does reset the TopTPTracker in its schedule method. Any derived,
target-specific scheduler will need to do it as well, but the TopRPTracker
is only exposed as a "const" object to derived classes. Without the ability
to modify the tracker directly, this leaves a derived scheduler with a
potential of having the TopRPTracker out-of-sync with the CurrentTop.

The symptom of the problem:
  void llvm::ScheduleDAGMILive::scheduleMI(llvm::SUnit *, bool):
  Assertion `TopRPTracker.getPos() == CurrentTop && "out of sync"' failed.

Differential Revision: http://reviews.llvm.org/D19438

llvm-svn: 267918
2016-04-28 19:17:44 +00:00
Adrian Prantl e5447574c8 Debug Info: Restore the pre-r240853 behavior for DWARF2 bitfields.
The DWARF2 specification of DW_AT_bit_offset is ambiguous for
little-endian machines, but by restoring to the old behavior
we match what debuggers expect and what other popular compilers
generate.

llvm-svn: 267896
2016-04-28 15:37:52 +00:00
Adrian Prantl f393d313ec Debug info: Support DWARF4 bitfields via DW_AT_data_bit_offset.
The DWARF2 specification of DW_AT_bit_offset was written from the perspective of
a big-endian machine with unclear semantics for other systems.  DWARF4
deprecated DW_AT_bit_offset and introduced a new attribute DW_AT_data_bit_offset
that simply counts the number of bits from the beginning of the containing
entity regardless of endianness.

After this patch LLVM emits DW_AT_bit_offset for DWARF 2 or 3 and
DW_AT_data_bit_offset when DWARF 4 or later is requested.

llvm-svn: 267895
2016-04-28 15:37:48 +00:00
Craig Topper 33772c5375 [CodeGen] Default CTTZ_ZERO_UNDEF/CTLZ_ZERO_UNDEF to Expand in TargetLoweringBase. This is what the majority of the targets want and removes a bunch of code. Set it to Legal explicitly in the few cases where that's the desired behavior.
llvm-svn: 267853
2016-04-28 03:34:31 +00:00
Matthias Braun fbe85ae12e CodeGen: Add DetectDeadLanes pass.
The DetectDeadLanes pass performs a dataflow analysis of used/defined
subregister lanes across COPY instructions and instructions that will
get lowered to copies. It detects dead definitions and uses reading
undefined values which are obscured by COPY and subregister usage.

These dead definitions cause trouble in the register coalescer which
cannot deal with definitions suddenly becoming dead after coalescing
COPY instructions.

For now the pass only adds dead and undef flags to machine operands. It
should be possible to extend it in the future to remove the dead
instructions and redo the analysis for the affected virtual
registers.

Differential Revision: http://reviews.llvm.org/D18427

llvm-svn: 267851
2016-04-28 03:07:16 +00:00
Matthias Braun c9e759acff LiveIntervalAnalysis: Fix handleMove() using wrong value numbers
handleMove() was incorrectly swapping two value numbers. This was missed
before because the problem only occured when moving subregister definitions
and needed -verify-machineinstrs to be detected.

I cannot add a testcase as long as I cannot reapply r260905/r260806.

llvm-svn: 267840
2016-04-28 02:11:49 +00:00
Quentin Colombet 12b69919a2 [ImplicitNullChecks] Properly update the live-in of the block of the memory operation.
We basically replace:
HoistBB:
cond_br NullBB, NotNullBB

NullBB:
  ...

NotNullBB:
  <reg> = load

into
HoistBB
<reg> = load_faulting_op NullBB
uncond_br NotNullBB

NullBB:
  ...

NotNullBB: ## <reg> is now live-in of NotNullBB
  ...

This partially fixes the machine verifier error for
test/CodeGen/X86/implicit-null-check.ll, but it still fails because
of the implicit CFG structure.

llvm-svn: 267817
2016-04-27 23:26:40 +00:00
Than McIntosh a541320908 Fix build failure under NDEBUG.
llvm-svn: 267774
2016-04-27 20:07:02 +00:00
David Majnemer 0c80e2eac6 [CodeGenPrepare] Don't sink a cast past its user
The sink cast machinery is supposed to sink casts as close to their user
as possible.  However, an EH pad is the first instruction in it's basic
block.  Don't sink if the user is an EH pad.

This fixes PR27536.

llvm-svn: 267767
2016-04-27 19:36:38 +00:00
Than McIntosh 1b60168576 Refactor debugging code, NFC.
Summary:
Refactor debugging routines to reduce code duplication. Remove a couple
of #include's that were not needed. Don't require MachineDominator as a
prereq for this pass (not needed).

These changes split off from http://reviews.llvm.org/D18827.

Reviewers: wmi, gbiv, qcolombet

Subscribers: llvm-commits, davidxl, jevinskie

Differential Revision: http://reviews.llvm.org/D18992

llvm-svn: 267766
2016-04-27 19:26:25 +00:00
Gerolf Hoflehner 50426191d7 [DAGCombiner] Follow coding convention for function name (NFC)
llvm-svn: 267745
2016-04-27 17:27:16 +00:00
Nico Weber e69b9548b8 Revert r267649, it caused PR27539.
llvm-svn: 267723
2016-04-27 15:16:54 +00:00
Cong Hou 6f879d9eb1 Detects the SAD pattern on X86 so that much better code will be emitted once the pattern is matched.
Differential revision: http://reviews.llvm.org/D14840

llvm-svn: 267649
2016-04-27 01:29:18 +00:00
Quentin Colombet ddad5aa152 [MachineInstrBundle] Actually set the PartialDeadDef flag only when the register
is defined!

The users were checking the proper thing (Defined + PartialDeadDef), but the
information may have been wrong for other use cases, so fix that.

llvm-svn: 267641
2016-04-27 00:16:29 +00:00
Quentin Colombet 08e79990a0 [MachineBasicBlock] Take advantage of the partially dead information.
Thanks to that information we wouldn't lie on a register being live whereas it
is not.

llvm-svn: 267622
2016-04-26 23:14:29 +00:00
Quentin Colombet 3f19245015 [MachineInstrBundle] Improvement the recognition of dead definitions.
Now, it is possible to know that partial definitions are dead definitions and
recognize that clobbered registers are also dead.

llvm-svn: 267621
2016-04-26 23:14:24 +00:00
Ahmed Bougacha 128f8732a5 [CodeGen] Add getBuildVector and getSplatBuildVector helpers. NFCI.
Differential Revision: http://reviews.llvm.org/D17176

llvm-svn: 267606
2016-04-26 21:15:30 +00:00
Krzysztof Parzyszek 4773f647bd [Tail duplication] Handle source registers with subregisters
When a block is tail-duplicated, the PHI nodes from that block are
replaced with appropriate COPY instructions. When those PHI nodes
contained use operands with subregisters, the subregisters were
dropped from the COPY instructions, resulting in incorrect code.

Keep track of the subregister information and use this information
when remapping instructions from the duplicated block.

Differential Revision: http://reviews.llvm.org/D19337

llvm-svn: 267583
2016-04-26 18:36:34 +00:00
Sanjay Patel d66607bd8c [CodeGenPrepare] use branch weight metadata to decide if a select should be turned into a branch
This is part of solving PR27344:
https://llvm.org/bugs/show_bug.cgi?id=27344

CGP should undo the SimplifyCFG transform for the same reason that earlier patches have used this
same mechanism: it's possible that passes between SimplifyCFG and CGP may be able to optimize the
IR further with a select in place.

For the TLI hook default, >99% taken or not taken is chosen as the default threshold for a highly
predictable branch. Even the most limited HW branch predictors will be correct on this branch almost
all the time, so even a massive mispredict penalty perf loss would be overcome by the win from all
the times the branch was predicted correctly.

As a follow-up, we could make the default target hook less conservative by using the SchedMachineModel's
MispredictPenalty. Or we could just let targets override the default by implementing the hook with that
and other target-specific options. Note that trying to statically determine mispredict rates for 
close-to-balanced profile weight data is generally impossible if the HW is sufficiently advanced. Ie, 
50/50 taken/not-taken might still be 100% predictable.

Finally, note that this patch as-is will not solve PR27344 because the current __builtin_unpredictable()
branch weight default values are 4 and 64. A proposal to change that is in D19435.

Differential Revision: http://reviews.llvm.org/D19488

llvm-svn: 267572
2016-04-26 17:11:17 +00:00
Sanjay Patel a31b0c0ece [CodeGenPrepare] don't convert an unpredictable select into control flow
Suggested in the review of D19488:
http://reviews.llvm.org/D19488

llvm-svn: 267504
2016-04-26 00:47:39 +00:00
Marcin Koscielnicki 1c1af6ef77 [PR27390] [CodeGen] Reject indexed loads in CombinerDAG.
visitAND, when folding and (load) forgets to check which output of
an indexed load is involved, happily folding the updated address
output on the following testcase:

target datalayout = "e-m:e-i64:64-n32:64"
target triple = "powerpc64le-unknown-linux-gnu"

%typ = type { i32, i32 }

define signext i32 @_Z8access_pP1Tc(%typ* %p, i8 zeroext %type) {
  %b = getelementptr inbounds %typ, %typ* %p, i64 0, i32 1
  %1 = load i32, i32* %b, align 4
  %2 = ptrtoint i32* %b to i64
  %3 = and i64 %2, -35184372088833
  %4 = inttoptr i64 %3 to i32*
  %_msld = load i32, i32* %4, align 4
  %zzz = add i32 %1,  %_msld
  ret i32 %zzz
}

Fix this by checking ResNo.

I've found a few more places that currently neglect to check for
indexed load, and tightened them up as well, but I don't have test
cases for them.  In fact, they might not be triggerable at all,
at least with current targets.  Still, better safe than sorry.

Differential Revision: http://reviews.llvm.org/D19202

llvm-svn: 267420
2016-04-25 15:43:44 +00:00
David Majnemer dd21523653 [WinEH] Update SplitAnalysis::computeLastSplitPoint to cope with multiple EH 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
2016-04-25 14:31:32 +00:00
Gerolf Hoflehner 01b3a6184a [MachineCombiner] Support for floating-point FMA on ARM64 (re-commit r267098)
The original patch caused crashes because it could derefence a null pointer
for SelectionDAGTargetInfo for targets that do not define it.

Evaluates fmul+fadd -> fmadd combines and similar code sequences in the
machine combiner. It adds support for float and double similar to the existing
integer implementation. The key features are:

- DAGCombiner checks whether it should combine greedily or let the machine
combiner do the evaluation. This is only supported on ARM64.
- It gives preference to throughput over latency: the heuristic used is
to combine always in loops. The targets decides whether the machine
combiner should optimize for throughput or latency.
- Supports for fmadd, f(n)msub, fmla, fmls patterns
- On by default at O3 ffast-math

llvm-svn: 267328
2016-04-24 05:14:01 +00:00
Craig Topper 36c133159a [CodeGen] Teach DAG combine to fold select_cc seteq X, 0, sizeof(X), ctlz_zero_undef(X) -> ctlz(X). InstCombine already does this for IR and X86 pattern matches this during isel.
A follow up commit will remove the X86 patterns to allow this to be tested.

llvm-svn: 267325
2016-04-24 04:38:32 +00:00
Duncan P. N. Exon Smith a59d3e5af8 DebugInfo: Remove MDString-based type references
Eliminate DITypeIdentifierMap and make DITypeRef a thin wrapper around
DIType*.  It is no longer legal to refer to a DICompositeType by its
'identifier:', and DIBuilder no longer retains all types with an
'identifier:' automatically.

Aside from the bitcode upgrade, this is mainly removing logic to resolve
an MDString-based reference to an actualy DIType.  The commits leading
up to this have made the implicit type map in DICompileUnit's
'retainedTypes:' field superfluous.

This does not remove DITypeRef, DIScopeRef, DINodeRef, and
DITypeRefArray, or stop using them in DI-related metadata.  Although as
of this commit they aren't serving a useful purpose, there are patchces
under review to reuse them for CodeView support.

The tests in LLVM were updated with deref-typerefs.sh, which is attached
to the thread "[RFC] Lazy-loading of debug info metadata":

  http://lists.llvm.org/pipermail/llvm-dev/2016-April/098318.html

llvm-svn: 267296
2016-04-23 21:08:00 +00:00
Sanjay Patel dc88bd6e1f replace duplicated static functions for profile metadata access with BranchInst member function; NFCI
llvm-svn: 267295
2016-04-23 20:01:22 +00:00
Craig Topper 7e5fad66f3 [CodeGen] When promoting CTTZ operations to larger type, don't insert a select to detect if the input is zero to return the original size instead of the extended size. Instead just set the first bit in the zero extended part.
llvm-svn: 267280
2016-04-23 05:20:47 +00:00
Andrew Kaylor aa641a5171 Re-commit optimization bisect support (r267022) without new pass manager support.
The original commit was reverted because of a buildbot problem with LazyCallGraph::SCC handling (not related to the OptBisect handling).

Differential Revision: http://reviews.llvm.org/D19172

llvm-svn: 267231
2016-04-22 22:06:11 +00:00
Peter Collingbourne 7dd8dbf486 Introduce llvm.load.relative intrinsic.
This intrinsic takes two arguments, ``%ptr`` and ``%offset``. It loads
a 32-bit value from the address ``%ptr + %offset``, adds ``%ptr`` to that
value and returns it. The constant folder specifically recognizes the form of
this intrinsic and the constant initializers it may load from; if a loaded
constant initializer is known to have the form ``i32 trunc(x - %ptr)``,
the intrinsic call is folded to ``x``.

LLVM provides that the calculation of such a constant initializer will
not overflow at link time under the medium code model if ``x`` is an
``unnamed_addr`` function. However, it does not provide this guarantee for
a constant initializer folded into a function body. This intrinsic can be
used to avoid the possibility of overflows when loading from such a constant.

Differential Revision: http://reviews.llvm.org/D18367

llvm-svn: 267223
2016-04-22 21:18:02 +00:00
Matt Arsenault 940d19a09c TLI: Only iterate over integer vector types
Instead of iterating over all vectors and skipping integers.

llvm-svn: 267220
2016-04-22 21:16:17 +00:00
Matt Arsenault 3b748d76f6 DAGCombiner: Relax alignment restriction when changing store type
If the target allows the alignment, this should be OK.

llvm-svn: 267217
2016-04-22 21:01:41 +00:00
Peter Collingbourne 265ebd7d70 CodeGen: Use PLT relocations for relative references to unnamed_addr functions.
The relative vtable ABI (PR26723) needs PLT relocations to refer to virtual
functions defined in other DSOs. The unnamed_addr attribute means that the
function's address is not significant, so we're allowed to substitute it
with the address of a PLT entry.

Also includes a bonus feature: addends for COFF image-relative references.

Differential Revision: http://reviews.llvm.org/D17938

llvm-svn: 267211
2016-04-22 20:40:10 +00:00
Matt Arsenault 629d12de70 DAGCombiner: Relax alignment restriction when changing load type
If the target allows the alignment, this should still be OK.

llvm-svn: 267209
2016-04-22 20:21:36 +00:00
Matthias Braun 4f57377c68 MachineScheduler: Move code to initialize a Candidate out of tryCandidate(); NFC
llvm-svn: 267191
2016-04-22 19:10:15 +00:00
Matthias Braun 6493bc2b97 MachineScheduler: Limit the size of the ready list.
Avoid quadratic complexity in unusually large basic blocks by limiting
the size of the ready lists.

Differential Revision: http://reviews.llvm.org/D19349

llvm-svn: 267189
2016-04-22 19:09:17 +00:00
Tom Stellard 2339f6f5a3 PostRAHazardRecocgnizer: Fix unused-private-field warning
llvm-svn: 267160
2016-04-22 15:11:08 +00:00
Tom Stellard ee34680bb0 CodeGen: Add a stand-alone hazard recognizer pass
Summary:
This new pass allows targets to use the hazard recognizer without having
to also run one of the schedulers.  This is useful when compiling with
optimizations disabled for targets that still need noop hazards
to be handled correctly.

Reviewers: hfinkel, atrick

Subscribers: arsenm, llvm-commits

Differential Revision: http://reviews.llvm.org/D18594

llvm-svn: 267156
2016-04-22 14:43:50 +00:00
Eric Liu 6be128e43d Fix -Wunused-variable in non-asserts build.
llvm-svn: 267128
2016-04-22 09:50:31 +00:00
Daniel Sanders 591c379563 Revert r267098 - [MachineCombiner] Support for floating-point FMA on ARM64
It introduced buildbot failures on clang-cmake-mips, clang-ppc64le-linux, among others.

llvm-svn: 267127
2016-04-22 09:37:26 +00:00
Vedant Kumar 6013f45f92 Revert "Initial implementation of optimization bisect support."
This reverts commit r267022, due to an ASan failure:

  http://lab.llvm.org:8080/green/job/clang-stage2-cmake-RgSan_check/1549

llvm-svn: 267115
2016-04-22 06:51:37 +00:00
Nicolai Haehnle b0c9748709 AMDGPU/SI: add llvm.amdgcn.ps.live intrinsic
Summary:
This intrinsic returns true if the current thread belongs to a live pixel
and false if it belongs to a pixel that we are executing only for derivative
computation. It will be used by Mesa to implement gl_HelperInvocation.

Note that for pixels that are killed during the shader, this implementation
also returns true, but it doesn't matter because those pixels are always
disabled in the EXEC mask.

This unearthed a corner case in the instruction verifier, which complained
about a v_cndmask 0, 1, exec, exec<imp-use> instruction. That's stupid but
correct code, so make the verifier accept it as such.

Reviewers: arsenm, tstellarAMD

Subscribers: arsenm, llvm-commits

Differential Revision: http://reviews.llvm.org/D19191

llvm-svn: 267102
2016-04-22 04:04:08 +00:00
Gerolf Hoflehner b32f11fc62 [MachineCombiner] Support for floating-point FMA on ARM64
Evaluates fmul+fadd -> fmadd combines and similar code sequences in the
machine combiner. It adds support for float and double similar to the existing
integer implementation. The key features are:

- DAGCombiner checks whether it should combine greedily or let the machine
combiner do the evaluation. This is only supported on ARM64.
- It gives preference to throughput over latency: the heuristic used is
to combine always in loops. The targets decides whether the machine
combiner should optimize for throughput or latency.
- Supports for fmadd, f(n)msub, fmla, fmls patterns
- On by default at O3 ffast-math

llvm-svn: 267098
2016-04-22 02:15:19 +00:00
David Blaikie f0f6c29cec Fix more -Wunused-variable in non-asserts build.
llvm-svn: 267077
2016-04-21 23:24:09 +00:00
David Blaikie 3d42a86f9d Fix some -Wunused-variable warnings in non-asserts builds.
llvm-svn: 267073
2016-04-21 22:53:33 +00:00
Derek Schuff 025191d42f Improve error message reporting for MachineFunctionProperties
When printing the properties required by a pass, only print the
properties that are set, and not those that are clear (only properties
that are set are verified, clear properties are "don't-care").

llvm-svn: 267070
2016-04-21 22:19:24 +00:00
Quentin Colombet 23341a84ca [MachineBasicBlock] Make the pass argument truly mandatory when
splitting edges.

MachineBasicBlock::SplitCriticalEdges will crash if a nullptr would have
been passed for the Pass argument. Do not allow that by turning this
argument into a reference.
The alternative would have been to make the Pass a truly optional
argument, but although this is easy to do, I was afraid users using it
like this would not be aware the livness information, dominator tree and
such would silently be broken.

llvm-svn: 267052
2016-04-21 21:01:13 +00:00
Quentin Colombet 77e1878954 [MachineBasicBlock] Refactor SplitCriticalEdge to expose a query API.
Introduce canSplitCriticalEdge, so that clients can now query whether or
not a critical edge can be split without actually needing to split it.
This may be useful when gathering information for cost models for
instance.

llvm-svn: 267046
2016-04-21 20:46:27 +00:00
Quentin Colombet c320fb4eae [RegisterBankInfo] Change the API for the verify methods.
Return bool instead of void so that it is natural to put the calls into
asserts.

llvm-svn: 267033
2016-04-21 18:34:43 +00:00
Matt Arsenault 7846d885ed LegalizeDAG: Move unaligned load/store expansion to TLI
When custom lowered, this is not called if the store is custom
lowered. Move it to be a utility function so targets can
easily expand unaligned accesses when custom lowering.

llvm-svn: 267029
2016-04-21 18:19:11 +00:00
Quentin Colombet 0e5ff58567 [RegisterBankInfo] Change the representation of the partial mappings.
Instead of holding a mask, hold two value: the start index and the
length of the mapping. This is a more compact representation, although
less powerful. That being said, arbitrary masks would not have worked
for the generic so do not allow them in the first place.

llvm-svn: 267025
2016-04-21 18:09:34 +00:00
Matt Arsenault 8d1052f55c DAGCombiner: Reduce 64-bit BFE pattern to pattern on 32-bit component
If the extracted bits are restricted to the upper half or lower half,
this can be truncated.

llvm-svn: 267024
2016-04-21 18:03:06 +00:00
Andrew Kaylor f0f279291c Initial implementation of optimization bisect support.
This patch implements a optimization bisect feature, which will allow optimizations to be selectively disabled at compile time in order to track down test failures that are caused by incorrect optimizations.

The bisection is enabled using a new command line option (-opt-bisect-limit).  Individual passes that may be skipped call the OptBisect object (via an LLVMContext) to see if they should be skipped based on the bisect limit.  A finer level of control (disabling individual transformations) can be managed through an addition OptBisect method, but this is not yet used.

The skip checking in this implementation is based on (and replaces) the skipOptnoneFunction check.  Where that check was being called, a new call has been inserted in its place which checks the bisect limit and the optnone attribute.  A new function call has been added for module and SCC passes that behaves in a similar way.

Differential Revision: http://reviews.llvm.org/D19172

llvm-svn: 267022
2016-04-21 17:58:54 +00:00
Amjad Aboud a5ba99140c Fixed Dwarf debug info emission to skip DILexicalBlockFile entries.
Before this fix, DILexicalBlockFile entries were skipped only in some cases and were not in other cases.

Differential Revision: http://reviews.llvm.org/D18724

llvm-svn: 267004
2016-04-21 16:58:49 +00:00
Craig Topper 52cb5ec36f [SelectionDAG] Teach LegalizeVectorOps to directly Expand CTTZ_ZERO_UNDEF/CTLZ_ZERO_UNDEF to CTTZ/CTLZ directly if those ops are Legal/Custom instead of deferring it to LegalizeOps.
This is needed to support CTTZ/CTLZ Custom correctly since LegalizeOps would be too late to do the custom lowering.

llvm-svn: 266951
2016-04-21 04:43:57 +00:00
Matthias Braun b550b765bd MachineSched: Cleanup; NFC
llvm-svn: 266946
2016-04-21 01:54:13 +00:00
Mehdi Amini ea0b1e7c17 ScoreboardHazardRecognizer: unbreak TSAN by moving a static mutated variable to a member
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266837
2016-04-20 00:21:24 +00:00
Tim Shen a1d8bc5597 [PPC, SSP] Support PowerPC Linux stack protection.
llvm-svn: 266809
2016-04-19 20:14:52 +00:00
Tim Shen e885d5e4d3 [SSP, 2/2] Create llvm.stackguard() intrinsic and lower it to LOAD_STACK_GUARD
With this change, ideally IR pass can always generate llvm.stackguard
call to get the stack guard; but for now there are still IR form stack
guard customizations around (see getIRStackGuard()). Future SSP
customization should go through LOAD_STACK_GUARD.

There is a behavior change: stack guard values are not CSEed anymore,
since we should never reuse the value in case that it has been spilled (and
corrupted). See ssp-guard-spill.ll. This also cause the change of stack
size and codegen in X86 and AArch64 test cases.

Ideally we'd like to know if the guard created in llvm.stackprotector() gets
spilled or not. If the value is spilled, discard the value and reload
stack guard; otherwise reuse the value. This can be done by teaching
register allocator to know how to rematerialize LOAD_STACK_GUARD and
force a rematerialization (which seems hard), or check for spilling in
expandPostRAPseudo. It only makes sense when the stack guard is a global
variable, which requires more instructions to load. Anyway, this seems to go out
of the scope of the current patch.

llvm-svn: 266806
2016-04-19 19:40:37 +00:00
Sanjoy Das 4519ff73df Add a description for the PatchableFunction pass; NFC
llvm-svn: 266721
2016-04-19 06:25:02 +00:00
Sanjoy Das c0441c29df Introduce a "patchable-function" function attribute
Summary:
The `"patchable-function"` attribute can be used by an LLVM client to
influence LLVM's code generation in ways that makes the generated code
easily patchable at runtime (for instance, to redirect control).
Right now only one patchability scheme is supported,
`"prologue-short-redirect"`, but this can be expanded in the future.

Reviewers: joker.eph, rnk, echristo, dberris

Subscribers: joker.eph, echristo, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D19046

llvm-svn: 266715
2016-04-19 05:24:47 +00:00
Paul Robinson 43d1e45347 [DWARF] Force a linkage_name on an inlined subprogram's abstract origin.
When we suppress linkage names, for a non-inlined subprogram the name
can still be found in the object-file symbol table, because we have
the code address of the subprogram.  This is not necessarily the case
for an inlined subprogram, so we still want to emit the linkage name
in the DWARF.  Put this on the abstract-origin DIE because it's common
to all inlined instances.

Differential Revision: http://reviews.llvm.org/D18706

llvm-svn: 266692
2016-04-18 22:41:41 +00:00
JF Bastien bbb0aee66e NFC: unify clang / LLVM atomic ordering
This makes the C11 / C++11 *ABI* atomic ordering accessible from LLVM,
as discussed in http://reviews.llvm.org/D18200#inline-151433

This re-applies r266573 which I had reverted in r266576.

Original review: http://reviews.llvm.org/D18875

llvm-svn: 266640
2016-04-18 18:01:43 +00:00
Mehdi Amini b550cb1750 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
2016-04-18 09:17:29 +00:00
JF Bastien fb9871b495 Revert "NFC: unify clang / LLVM atomic ordering"
This reverts commit 537951f2f16d6a8542571c7722fcbae07d4e62c2.

Causes an assert in:
  test/Transforms/AtomicExpand/SPARC/libcalls.ll
  (Ordering2 != AtomicOrdering::NotAtomic && "expect atomic MO")

Bot:
  http://lab.llvm.org:8080/green/job/clang-stage1-cmake-RA-incremental_check/21724/testReport/junit/LLVM/Transforms_AtomicExpand_SPARC/libcalls_ll/

I'm not getting this assert on my local debug build, but I'll revert
just to be sure.

llvm-svn: 266576
2016-04-17 21:29:01 +00:00
JF Bastien 6ef3aa2b7e NFC: unify clang / LLVM atomic ordering
Summary: This makes the C11 / C++11 *ABI* atomic ordering accessible from LLVM, as discussed in http://reviews.llvm.org/D18200#inline-151433

Reviewers: jyknight, reames

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18875

llvm-svn: 266573
2016-04-17 21:00:57 +00:00
Davide Italiano caa1169653 [ParallelCG] SmallVector<char> -> SmallString.
llvm-svn: 266568
2016-04-17 19:38:57 +00:00
Rafael Espindola 3c1c9875b9 Keep only the splitCodegen version that takes a factory.
This makes it much easier to see that all created TargetMachines are
equivalent.

llvm-svn: 266564
2016-04-17 18:42:27 +00:00
Mehdi Amini 47b292d3fd Remove some unneeded headers and replace some headers with forward class declarations (NFC)
Differential Revision: http://reviews.llvm.org/D19154

Patch by Eugene Kosov <claprix@yandex.ru>

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266524
2016-04-16 07:51:28 +00:00
Mehdi Amini 59ae854503 Do not modify a cl::opt programmatically, global mutable state is evil.
Found by TSAN on ThinLTO.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266514
2016-04-16 04:58:30 +00:00
Richard Smith 2db6f2e508 Update and fix LLVM_ENABLE_MODULES:
1) We need to add this flag prior to adding any other, in case the user has
specified a -fmodule-cache-path= flag in their custom CXXFLAGS. Such a flag
causes -Werror builds to fail, and thus all config checks fail, until we add
the corresponding -fmodules flag. The modules selfhost bot does this, for
instance.

2) Delete module maps that were putting .cpp files into modules.

3) Enable -fmodules-local-submodule-visibility, to get proper module
visibility rules applied across submodules of the same module. Disable
-fmodules for C builds, since that flag is not available there.

llvm-svn: 266502
2016-04-16 00:48:58 +00:00
Wei Mi 963f2df4d2 Don't skip splitSeparateComponents in eliminateDeadDefs for HoistSpillHelper::hoistAllSpills.
Because HoistSpillHelper::hoistAllSpills is called in postOptimization, before the
patch we didn't want LiveRangeEdit::eliminateDeadDefs to call splitSeparateComponents
and generate unassigned new vregs. However, skipping splitSeparateComponents will make
verify-machineinstrs unhappy, so I remove the early return, and use
HoistSpillHelper::LRE_DidCloneVirtReg to assign physreg/stackslot for those new vregs.

In addition, some code reorganization to make class HoistSpillHelper privately inheriting
from LiveRangeEdit::Delegate possible. This is to be consistent with class RAGreedy and
class RegisterCoalescer.

Differential Revision: http://reviews.llvm.org/D19142

llvm-svn: 266489
2016-04-15 23:16:44 +00:00
Hans Wennborg 07f6d3a893 Switch lowering: don't add incoming PHI values from skipped bit test MBB's (PR27135)
After r245976, LLVM will skip the last bit test case if knows it will always be
true. However, we would still erroneously update PHI nodes with incoming values
from the MBB that would perform the final bit test, causing -verify-machineinstrs
to fail.

llvm-svn: 266479
2016-04-15 21:45:30 +00:00
Hans Wennborg c944c13dc1 SelectionDAGISel: rangeify a loop
llvm-svn: 266478
2016-04-15 21:45:09 +00:00
Davide Italiano 7950b12957 [ParallelCG] Add a new splitCodeGen() API which takes a TargetMachineFactory.
This is a recommit of r266390 with a fix that will allow tests to pass
(hopefully). Before we got a StringRef to M->getTargetTriple() and right
after we moved the Module so we were referencing a dangling object.

llvm-svn: 266456
2016-04-15 17:34:32 +00:00
Adrian Prantl 75819aedf6 [PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

llvm-svn: 266446
2016-04-15 15:57:41 +00:00
Jun Bum Lim 4c5bd58ebe [MachineScheduler]Add support for store clustering
Perform store clustering just like load clustering. This change add
StoreClusterMutation in machine-scheduler. To control StoreClusterMutation,
added enableClusterStores() in TargetInstrInfo.h. This is enabled only on
AArch64 for now.

This change also add support for unscaled stores which were not handled in
getMemOpBaseRegImmOfs().

llvm-svn: 266437
2016-04-15 14:58:38 +00:00
Davide Italiano 2abf2e7c8c Revert "[LTO] Add a new splitCodeGen() API which takes a TargetMachineFactory."
This reverts commits r266390 and r266396 as they broke some bots.

llvm-svn: 266408
2016-04-15 02:07:03 +00:00
Justin Lebar 7dba2e0d0c [ifcnv] Don't duplicate blocks that contain convergent instructions.
It's unsafe to duplicate blocks that contain convergent instructions
during ifcnv.  See the patch for details.

Reviewers: hfinkel

Differential Revision: http://reviews.llvm.org/D17518

llvm-svn: 266404
2016-04-15 01:38:41 +00:00
Davide Italiano 3fdd27df03 [LTO] Add a new splitCodeGen() API which takes a TargetMachineFactory.
This will be used in lld to avoid creating TargetMachine in two
different places. See D18999 for a more detailed discussion.

Differential Revision:  http://reviews.llvm.org/D19139

llvm-svn: 266390
2016-04-15 00:07:28 +00:00
Geoff Berry 6381713b37 [ScheduleDAGInstrs] Re-factor for based on review feedback. NFC.
Summary:
Re-factor some code to improve clarity and style based on review
comments from http://reviews.llvm.org/D18093.

Reviewers: MatzeB, mcrosier

Subscribers: MatzeB, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D19128

llvm-svn: 266372
2016-04-14 21:31:07 +00:00
Reid Kleckner 28865809fe Sink DI metadata usage out of MachineInstr.h and MachineInstrBuilder.h
MachineInstr.h and MachineInstrBuilder.h are very popular headers,
widely included across all LLVM backends. It turns out that there only a
handful of TUs that actually care about DI operands on MachineInstrs.

After this change, touching DebugInfoMetadata.h and rebuilding llc only
needs 112 actions instead of 542.

llvm-svn: 266351
2016-04-14 18:29:59 +00:00
Tom Stellard b72a65ff53 [GlobalISel] Coding style and whitespace fixes
Reviewers: qcolombet

Subscribers: joker.eph, llvm-commits, vkalintiris

Differential Revision: http://reviews.llvm.org/D19119

llvm-svn: 266342
2016-04-14 17:23:33 +00:00
David Majnemer 0f26b0aeb4 [CodeGen] Teach LLVM how to lower @llvm.{min,max}num to {MIN,MAX}NAN
The behavior of {MIN,MAX}NAN differs from that of {MIN,MAX}NUM when only
one of the inputs is NaN: -NUM will return the non-NaN argument while
-NAN would return NaN.

It is desirable to lower to @llvm.{min,max}num to -NAN if they don't
have a native instruction for -NUM.  Notably, ARMv7 NEON's vmin has the
-NAN semantics.

N.B.  Of course, it is only safe to do this if the intrinsic call is
marked nnan.

llvm-svn: 266279
2016-04-14 07:13:24 +00:00
Matt Arsenault 9cd90712f0 AMDGPU: Implement canonicalize
Also add generic DAG node for it.

llvm-svn: 266272
2016-04-14 01:42:16 +00:00
Matthias Braun 46b0f03e12 TargetLowering: Factor out common code for tail call eligibility checking; NFC
llvm-svn: 266270
2016-04-14 01:10:42 +00:00
Nirav Dave 2477491a92 Cleanup Store Merging in UseAA case
This patch fixes a bug (PR26827) when using anti-aliasing in store
merging. This sets the chain users of the component stores to point to
the new store instead of the component stores chain parent.

Reviewers: jyknight

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18909

llvm-svn: 266217
2016-04-13 17:27:26 +00:00
Petar Jovanovic 644b8c1a5d Calculate __builtin_object_size when pointer depends on a condition
This patch fixes calculating of builtin_object_size if it depends on a
condition. Before this patch compiler did not know how to calculate the
object size when it finds a condition that cannot be eliminated.
This patch enables calculating of builtin_object_size even in case when
condition cannot be eliminated by choosing minimum or maximum value as a
result from condition. Choosing minimum or maximum value from condition
is based on the second argument of __builtin_object_size function.

Patch by Strahinja Petrovic.

Differential Revision: http://reviews.llvm.org/D18438

llvm-svn: 266193
2016-04-13 12:25:25 +00:00
Wei Mi 9a16d655c7 Recommit r265547, and r265610,r265639,r265657 on top of it, plus
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
2016-04-13 03:08:27 +00:00
Justin Bogner 263f314ba7 CodeGen: Clear the MFI's save and restore point after PrologEpilogInserter
This state is no longer useful and not guaranteed to be valid in later
codegen passes. For example, see the added test, which would print a
savepoint of %bb.-1 without this change, and crashes with a
use-after-free error under ASan if you apply the recycling allocator
patch from llvm.org/PR26808.

llvm-svn: 266150
2016-04-12 23:21:53 +00:00
James Y Knight 7873fb9d73 Pre-fill LibcallRoutineNames with nullptr.
And rearrange InitLibcallNames slightly.

llvm-svn: 266142
2016-04-12 22:32:47 +00:00
James Y Knight 19f6cce4e3 Add __atomic_* lowering to AtomicExpandPass.
(Recommit of r266002, with r266011, r266016, and not accidentally
including an extra unused/uninitialized element in LibcallRoutineNames)

AtomicExpandPass can now lower atomic load, atomic store, atomicrmw, and
cmpxchg instructions to __atomic_* library calls, when the target
doesn't support atomics of a given size.

This is the first step towards moving all atomic lowering from clang
into llvm. When all is done, the behavior of __sync_* builtins,
__atomic_* builtins, and C11 atomics will be unified.

Previously LLVM would pass everything through to the ISelLowering
code. There, unsupported atomic instructions would turn into __sync_*
library calls. Because of that behavior, Clang currently avoids emitting
llvm IR atomic instructions when this would happen, and emits __atomic_*
library functions itself, in the frontend.

This change makes LLVM able to emit __atomic_* libcalls, and thus will
eventually allow clang to depend on LLVM to do the right thing.

It is advantageous to do the new lowering to atomic libcalls in
AtomicExpandPass, before ISel time, because it's important that all
atomic operations for a given size either lower to __atomic_*
libcalls (which may use locks), or native instructions which won't. No
mixing and matching.

At the moment, this code is enabled only for SPARC, as a
demonstration. The next commit will expand support to all of the other
targets.

Differential Revision: http://reviews.llvm.org/D18200

llvm-svn: 266115
2016-04-12 20:18:48 +00:00
Ahmed Bougacha 7ac86c47d2 [CodeGen] Remove constant-folding dead code. NFC.
This code was specific to vector operations with scalar operands:
all the opcodes in FoldValue (via FoldConstantArithmetic) can't
match those criteria.

Replace it with an assert if that ever changes: at that point,
we might need to add back a splat BUILD_VECTOR.

llvm-svn: 266100
2016-04-12 18:15:39 +00:00
Philip Reames 92d1f0cb6d Introduce an GCRelocateInst class [NFC]
Previously, we were using isGCRelocate predicates.  Using a subclass of IntrinsicInst is far more idiomatic.  The refactoring also enables a couple of minor simplifications and code sharing.

llvm-svn: 266098
2016-04-12 18:05:10 +00:00
Geoff Berry c0739d8305 [ScheduleDAGInstrs] Handle instructions with multiple MMOs
Summary:
In getUnderlyingObjectsForInstr(): Don't give up on instructions with
multiple MMOs, instead look through all the MMOs and if they all meet
the conservative criteria previously used for single MMO instructions,
then return all of the underlying objects derived from the MMOs.

The change to ScheduleDAGInstrs::buildSchedGraph() is needed to avoid
the case where multiple underlying objects are present and are related
in such a way that successive iterations of the loop end up adding a
dependency from an instruction to itself.

Reviewers: atrick, hfinkel

Subscribers: MatzeB, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D18093

llvm-svn: 266084
2016-04-12 15:50:19 +00:00
Rafael Espindola d41b54be11 This reverts commit r266002, r266011 and r266016.
They broke the msan bot.

Original message:

Add __atomic_* lowering to AtomicExpandPass.

AtomicExpandPass can now lower atomic load, atomic store, atomicrmw,and
cmpxchg instructions to __atomic_* library calls, when the target
doesn't support atomics of a given size.

This is the first step towards moving all atomic lowering from clang
into llvm. When all is done, the behavior of __sync_* builtins,
__atomic_* builtins, and C11 atomics will be unified.

Previously LLVM would pass everything through to the ISelLowering
code. There, unsupported atomic instructions would turn into __sync_*
library calls. Because of that behavior, Clang currently avoids emitting
llvm IR atomic instructions when this would happen, and emits __atomic_*
library functions itself, in the frontend.

This change makes LLVM able to emit __atomic_* libcalls, and thus will
eventually allow clang to depend on LLVM to do the right thing.

It is advantageous to do the new lowering to atomic libcalls in
AtomicExpandPass, before ISel time, because it's important that all
atomic operations for a given size either lower to __atomic_*
libcalls (which may use locks), or native instructions which won't. No
mixing and matching.

At the moment, this code is enabled only for SPARC, as a
demonstration. The next commit will expand support to all of the other
targets.

Differential Revision: http://reviews.llvm.org/D18200

llvm-svn: 266062
2016-04-12 12:30:25 +00:00
Quentin Colombet 777a7717ef [RegBankSelect] Teach the repairing code how to handle physical
registers.

llvm-svn: 266029
2016-04-12 00:38:51 +00:00
Quentin Colombet 5aacb1da00 [RegisterBankInfo] Do not provide a default mapping for non-reg of phi
operations.

llvm-svn: 266027
2016-04-12 00:30:14 +00:00
Quentin Colombet 904a2c7422 [RegBankSelect] Teach how to repair definitions.
Although repairing definitions is not mandatory for correctness (only
phis would be impacted because of the RPO traversal), not repairing
might go against the cost model. Therefore, just repair when it is
possible.

llvm-svn: 266025
2016-04-12 00:12:59 +00:00
Derek Schuff f7b2bce1f1 Replace MachineRegisterInfo::TracksLiveness with a MachineFunctionProperty
Use the MachineFunctionProperty mechanism to indicate whether the
liveness info is accurate instead of a bool flag on MRI.
Keeps the MRI accessor function for convenience. NFC

Differential Revision: http://reviews.llvm.org/D18767

llvm-svn: 266020
2016-04-11 23:32:13 +00:00
JF Bastien b3ac75f748 AtomicExpandPass: mark assert variable as used
Avoid -Wunused-variable

llvm-svn: 266016
2016-04-11 23:03:54 +00:00
James Y Knight 00db547f97 Fix compile with GCC after r266002 (Add __atomic_* lowering to AtomicExpandPass)
It doesn't like implicitly calling the ArrayRef constructor with a
returned array -- it appears to decays the returned value to a pointer,
first, before trying to make an ArrayRef out of it.

llvm-svn: 266011
2016-04-11 22:52:42 +00:00
Justin Bogner 1faf01578e CodeGen: Fix a use-after-free in TailDuplication
The call to processPHI already erased MI from its parent, so MI isn't
even valid here, making the getParent() call a use-after-free in
addition to being redundant.

Found by ASan with the ArrayRecycler changes in llvm.org/pr26808.

llvm-svn: 266008
2016-04-11 22:37:13 +00:00
Evgeniy Stepanov f17120a85f [safestack] Add canary to unsafe stack frames
Add StackProtector to SafeStack. This adds limited protection against
data corruption in the caller frame. Current implementation treats
all stack protector levels as -fstack-protector-all.

llvm-svn: 266004
2016-04-11 22:27:48 +00:00
James Y Knight b91d38c5fe Add __atomic_* lowering to AtomicExpandPass.
AtomicExpandPass can now lower atomic load, atomic store, atomicrmw, and
cmpxchg instructions to __atomic_* library calls, when the target
doesn't support atomics of a given size.

This is the first step towards moving all atomic lowering from clang
into llvm. When all is done, the behavior of __sync_* builtins,
__atomic_* builtins, and C11 atomics will be unified.

Previously LLVM would pass everything through to the ISelLowering
code. There, unsupported atomic instructions would turn into __sync_*
library calls. Because of that behavior, Clang currently avoids emitting
llvm IR atomic instructions when this would happen, and emits __atomic_*
library functions itself, in the frontend.

This change makes LLVM able to emit __atomic_* libcalls, and thus will
eventually allow clang to depend on LLVM to do the right thing.

It is advantageous to do the new lowering to atomic libcalls in
AtomicExpandPass, before ISel time, because it's important that all
atomic operations for a given size either lower to __atomic_*
libcalls (which may use locks), or native instructions which won't. No
mixing and matching.

At the moment, this code is enabled only for SPARC, as a
demonstration. The next commit will expand support to all of the other
targets.

Differential Revision: http://reviews.llvm.org/D18200

llvm-svn: 266002
2016-04-11 22:22:33 +00:00
Simon Pilgrim 82e54871d0 [DAGCombiner] Fold xor/and/or (bitcast(A), bitcast(B)) -> bitcast(op (A,B)) anytime before LegalizeVectorOprs
xor/and/or (bitcast(A), bitcast(B)) -> bitcast(op (A,B)) was only being combined at the AfterLegalizeTypes stage, this patch permits the combine to occur anytime before then as well.

The main aim with this to improve the ability to recognise bitmasks that can be converted to shuffles.

I had to modify a number of AVX512 mask tests as the basic bitcast to/from scalar pattern was being stripped out, preventing testing of the mmask bitops. By replacing the bitcasts with loads we can get almost the same result.

Differential Revision: http://reviews.llvm.org/D18944

llvm-svn: 265998
2016-04-11 21:10:33 +00:00
Hans Wennborg e9134897f4 Fix a couple of redundant conditional expressions (PR27283, PR28282)
llvm-svn: 265987
2016-04-11 20:35:01 +00:00
Sanjay Patel 892f167aa5 use range-loops; NFCI
llvm-svn: 265985
2016-04-11 20:13:44 +00:00
Reid Kleckner b6800b3052 Combine redundant stack realignment booleans in MachineFrameInfo
MachineFrameInfo does not need to be able to distinguish between the
user asking us not to realign the stack and the target telling us it
doesn't support stack realignment. Either way, fixed stack objects have
their alignment clamped.

llvm-svn: 265971
2016-04-11 17:54:03 +00:00
Tom Stellard 52686e4182 TargetRegisterInfo: Add getRegAsmName()
Summary:
The motivation for this new function is to move an invalid assumption
about the relationship between the names of register definitions in
tablegen files and their assembly names into TargetRegisterInfo, so that
we can begin working on fixing this assumption.

The current problem is that if you have a register definition in
TableGen like:

def MYReg0 : Register<"r0", 0>;

The function TargetLowering::getRegForInlineAsmConstraint() derives the
assembly name from the tablegen name: "MyReg0" rather than the given
assembly name "r0".  This is working, because on most targets the
tablegen name and the assembly names are case insensitive matches for
each other (e.g. def EAX : X86Reg<"eax", ...>

getRegAsmName() will allow targets to override this default assumption and
return the correct assembly name.

Reviewers: echristo, hfinkel

Subscribers: SamWot, echristo, hfinkel, llvm-commits

Differential Revision: http://reviews.llvm.org/D15614

llvm-svn: 265955
2016-04-11 16:21:12 +00:00
Charles Davis 2f65f35c27 [CodeGen] Don't assume that fixed stack objects are aligned in a stack-realigned function.
Summary:
After we make the adjustment, we can assume that for local allocas, but
not for stack parameters, the return address, or any other fixed stack
object (which has a negative offset and therefore lies prior to the
adjusted SP).

Fixes PR26662.

Reviewers: hfinkel, qcolombet, rnk

Subscribers: rnk, llvm-commits

Differential Revision: http://reviews.llvm.org/D18471

llvm-svn: 265886
2016-04-09 23:34:42 +00:00
Adrian Prantl 3891e9e859 Drop debug info for DISubprograms that are not referenced by anything
This patch drops the debug info for all DISubprograms that are
(a) not attached to an llvm::Function and
(b) not indirectly reachable via inline scopes from any surviving Function and
(c) not reachable from a type (i.e.: member functions).

Background: I'm currently working on a patch to reverse the pointers
between DICompileUnit and DISubprogram (for more info check Duncan's RFC
on lazy-loading of debug info metadata
http://lists.llvm.org/pipermail/llvm-dev/2016-March/097419.html).
The idea is to remove the list of subprograms from DICompileUnit and
instead point to the owning compile unit from each DISubprogram.
After doing this all DISubprograms fulfilling the above criteria will be
implicitly dropped unless we go through an extra effort to preserve them.

http://reviews.llvm.org/D18477
<rdar://problem/25256815>

llvm-svn: 265876
2016-04-09 18:10:22 +00:00
Sanjay Patel 4abae4e0fa [x86] use BMI 'andn' for logic + compare ops
With BMI, we can use 'andn' to save an instruction when the result is only used in a compare.
This is related to one of the potential sequences to check 'isfinite' in:
https://llvm.org/bugs/show_bug.cgi?id=27164

Differential Revision: http://reviews.llvm.org/D18910

llvm-svn: 265875
2016-04-09 16:02:52 +00:00
Adrian Prantl 5992a72b4d Support the Nodebug emission kind for DICompileUnits.
Sample-based profiling and optimization remarks currently remove
DICompileUnits from llvm.dbg.cu to suppress the emission of debug info
from them. This is somewhat of a hack and only borderline legal IR.

This patch uses the recently introduced NoDebug emission kind in
DICompileUnit to achieve the same result without breaking the Verifier.
A nice side-effect of this change is that it is now possible to combine
NoDebug and regular compile units under LTO.

http://reviews.llvm.org/D18808
<rdar://problem/25427165>

llvm-svn: 265861
2016-04-08 22:43:03 +00:00
Tim Shen 0012756489 [SSP] Remove llvm.stackprotectorcheck.
This is a cleanup patch for SSP support in LLVM. There is no functional change.
llvm.stackprotectorcheck is not needed, because SelectionDAG isn't
actually lowering it in SelectBasicBlock; rather, it adds check code in
FinishBasicBlock, ignoring the position where the intrinsic is inserted
(See FindSplitPointForStackProtector()).

llvm-svn: 265851
2016-04-08 21:26:31 +00:00
Kyle Butt 3232dbbf02 Codegen: Factor tail duplication into a utility class. NFC
This is in preparation for tail duplication during block placement. See D18226.
This needs to be a utility class for 2 reasons. No passes may run after block
placement, and also, tail-duplication affects subsequent layout decisions, so
it must be interleaved with placement, and can't be separated out into its own
pass. The original pass is still useful, and now runs by delegating to the
utility class.

llvm-svn: 265842
2016-04-08 20:35:01 +00:00
Nirav Dave 66f485f4e2 Fix Load Control Dependence in MemCpy Generation
In Memcpy lowering we had missed a dependence from the load of the
operation to successor operations. This causes us to potentially
construct an in initial DAG with a memory dependence not fully
represented in the chain sub-DAG but rather require looking at the
entire DAG breaking alias analysis by allowing incorrect repositioning
of memory operations.

To work around this, r200033 changed DAGCombiner::GatherAllAliases to be
conservative if any possible issues to happen. Unfortunately this check
forbade many non-problematic situations as well. For example, it's
common for incoming argument lowering to add a non-aliasing load hanging
off of EntryNode. Then, if GatherAllAliases visited EntryNode, it would
find that other (unvisited) use of the EntryNode chain, and just give up
entirely. Furthermore, the check was incomplete: it would not actually
detect all such potentially problematic DAG constructions, because
GatherAllAliases did not guarantee to visit all chain nodes going up to
the root EntryNode. This is in general fine -- giving up early will just
miss a potential optimization, not generate incorrect results. But, for
this non-chain dependency detection code, it's possible that you could
have a load attached to a higher-up chain node than any which were
visited. If that load aliases your store, but the only dependency is
through the value operand of a non-aliasing store, it would've been
missed by this code, and potentially reordered.

With the dependence added, this check can be removed and Alias Analysis
can be much more aggressive. This fixes code quality regression in the
Consecutive Store Merge cleanup (D14834).

Test Change:

ppc64-align-long-double.ll now may see multiple serializations
of its stores

Differential Revision: http://reviews.llvm.org/D18062

llvm-svn: 265836
2016-04-08 19:44:40 +00:00
Quentin Colombet ab8c21f72b [RegBankSelect] Use reverse post order traversal.
When assigning the register banks of an instruction, it is best to know
all the constraints of the input to have a good idea of how this will
impact the cost of the whole function.

llvm-svn: 265812
2016-04-08 17:19:10 +00:00
Quentin Colombet 88805c1917 [RegisterBankInfo] Change the implementation for the default mapping.
Do not give that much importance to the current register bank of an
operand. This is likely just a side effect of the current execution and
it is properly wise to prefer a register bank that can be extracted from
the information available statically (like encoding constraints and
type).

llvm-svn: 265810
2016-04-08 16:59:50 +00:00
Quentin Colombet 6d6d6af226 [RegBankSelect] Improve debug output.
Add verbose information when checking if the current and the desired
register banks match.
Detail what happens when we assign a register bank.

llvm-svn: 265804
2016-04-08 16:48:16 +00:00
Quentin Colombet 876ddf8107 [MIR] Teach the parser how to deal with register banks.
llvm-svn: 265802
2016-04-08 16:40:43 +00:00
Quentin Colombet c1c94bc2ca [MachineVerifier] Teach how to check some of the properties of generic
virtual registers.

Generic virtual registers:
- May not have a register class
- May not have a register bank
- If they do not have a register class they must have a size
- If they have a register bank, the size of the register bank must be
  greater or equal to the size of the virtual register (basically check
  that the virtual register will fit into that register class)

llvm-svn: 265798
2016-04-08 16:35:22 +00:00
Quentin Colombet fab1cfe673 [MIR] Teach the mir printer how to print the register bank.
For now, we put the register bank in the Class field since a register
may only have one of those at a given time. The downside of that
representation is that if a register class and a register bank have the
same name, we will not be able to distinguish them.

llvm-svn: 265796
2016-04-08 16:26:22 +00:00
Hans Wennborg 5a7723c7a2 Revert r265547 "Recommit r265309 after fixed an invalid memory reference bug 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
2016-04-08 15:17:43 +00:00
Chuang-Yu Cheng 98c1894755 CXX_FAST_TLS calling convention: performance improvement for PPC64
This is the same change on PPC64 as r255821 on AArch64. I have even borrowed
his commit message.

The access function has a short entry and a short exit, the initialization
block is only run the first time. To improve the performance, we want to
have a short frame at the entry and exit.

We explicitly handle most of the CSRs via copies. Only the CSRs that are not
handled via copies will be in CSR_SaveList.

Frame lowering and prologue/epilogue insertion will generate a short frame
in the entry and exit according to CSR_SaveList. The majority of the CSRs will
be handled by register allcoator. Register allocator will try to spill and
reload them in the initialization block.

We add CSRsViaCopy, it will be explicitly handled during lowering.

1> we first set FunctionLoweringInfo->SplitCSR if conditions are met (the target
   supports it for the given machine function and the function has only return
   exits). We also call TLI->initializeSplitCSR to perform initialization.
2> we call TLI->insertCopiesSplitCSR to insert copies from CSRsViaCopy to
   virtual registers at beginning of the entry block and copies from virtual
   registers to CSRsViaCopy at beginning of the exit blocks.
3> we also need to make sure the explicit copies will not be eliminated.

Author: Tom Jablin (tjablin)
Reviewers: hfinkel kbarton cycheng

http://reviews.llvm.org/D17533

llvm-svn: 265781
2016-04-08 12:04:32 +00:00
Craig Topper 00230805f2 Use std::fill to simplify some code. NFC
llvm-svn: 265771
2016-04-08 07:10:46 +00:00
Quentin Colombet e57546de40 [TargetRegisterInfo] Re-apply r265734.
Original commit message:
[TargetRegisterInfo] Refactor the code to use BitMaskClassIterator.

llvm-svn: 265764
2016-04-08 00:51:00 +00:00
Adrian Prantl 3e9c88753b DwarfDebug: Support floating point constants in location lists.
This patch closes a gap in the DWARF backend that caused LLVM to drop
debug info for floating point variables that were constant for part of
their scope. Floating point constants are emitted as one or more
DW_OP_constu joined via DW_OP_piece.

This fixes a regression caught by the LLDB testsuite that I introduced
in r262247 when we stopped blindly expanding the range of singular
DBG_VALUEs to span the entire scope and started to emit location lists
with accurate ranges instead.

Also deletes a now-impossible testcase (debug-loc-empty-entries).

<rdar://problem/25448338>

llvm-svn: 265760
2016-04-08 00:38:37 +00:00
Quentin Colombet e0a7ffa6cb Revert "[TargetRegisterInfo] Refactor the code to use BitMaskClassIterator."
This reverts commit r265734.
Looks like ASan is not happy about it.
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/11741

Looking.

llvm-svn: 265755
2016-04-08 00:03:51 +00:00
Quentin Colombet dcf5cf6a29 [RegisterBankInfo] Make the debug output more compact.
Print the mask of the partial mapping as an hexadecimal instead of a
binary value.

llvm-svn: 265754
2016-04-08 00:03:49 +00:00
Quentin Colombet e16f561d91 [RegBankSelect] Add a few debug statements.
llvm-svn: 265749
2016-04-07 23:53:55 +00:00
Quentin Colombet 9a2ae85e67 [RegisterBankInfo] Add print and dump method to the InstructionMapping
helper class.

llvm-svn: 265747
2016-04-07 23:31:58 +00:00
Quentin Colombet e087c9fc12 [RegisterBankInfo] Add print and dump method to the ValueMapping helper
class.

llvm-svn: 265746
2016-04-07 23:25:43 +00:00
Quentin Colombet 03c419628e [MachineInstr] Teach the print method about RegisterBank.
Properly print either the register class or the register bank or a
virtual register.
Get rid of a few ifdefs in the process.

llvm-svn: 265745
2016-04-07 23:18:11 +00:00
Quentin Colombet ac40034e06 [RegisterBankInfo] Strengthen getInstrMappingImpl.
Teach the target independent code how to take advantage of type
information to get the mapping of an instruction.

llvm-svn: 265739
2016-04-07 22:52:49 +00:00
Quentin Colombet e918006a87 [RegisterBankInfo] Add a way to record what register bank covers a
specific type.

This will be used to find the default mapping of the instruction.
Also, this information is recorded, instead of computed, because it is
expensive from a type to know which register bank maps it.
Indeed, we need to iterate through all the register classes of all the
register banks to find the one that maps the given type.

llvm-svn: 265736
2016-04-07 22:45:42 +00:00
Quentin Colombet c8d612f6fd [RegisterBankInfo] Introduce getRegBankFromConstraints as an helper
method.

NFC.

The refactoring intends to make the code more readable and expose
more features to potential derived classes.

llvm-svn: 265735
2016-04-07 22:35:03 +00:00
Quentin Colombet 2445dc1916 [TargetRegisterInfo] Refactor the code to use BitMaskClassIterator.
llvm-svn: 265734
2016-04-07 22:16:56 +00:00
Quentin Colombet cf477ffc58 [RegisterBankInfo] Refactor the code to use BitMaskClassIterator.
llvm-svn: 265733
2016-04-07 22:08:56 +00:00
Quentin Colombet aac71a4a0e [RegBankSelect] Reuse RegisterBankInfo logic to get to the register bank
from a register.
On top of duplicating the logic, it was buggy! It would assert on
physical registers, since MachineRegisterInfo does not have any
information regarding register classes/banks for them.

llvm-svn: 265727
2016-04-07 21:32:23 +00:00
Amaury Sechet c53ad4f3b2 Do not select EhPad BB in MachineBlockPlacement when there is regular BB to schedule
Summary:
EHPad BB are not entered the classic way and therefor do not need to be placed after their predecessors. This patch make sure EHPad BB are not chosen amongst successors to form chains, and are selected as last resort when selecting the best candidate.

EHPad are scheduled in reverse probability order in order to have them flow into each others naturally.

Reviewers: chandlerc, majnemer, rafael, MatzeB, escha, silvas

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D17625

llvm-svn: 265726
2016-04-07 21:29:39 +00:00
Quentin Colombet d4131814b3 [GlobalISel] Add RegBankSelect hooks into the pass pipeline.
Now, RegBankSelect will happen after the IRTranslation and the target
may optionally add additional passes in between.

llvm-svn: 265716
2016-04-07 20:27:33 +00:00
Quentin Colombet 40ad573d2c [RegBankSelect] Initial implementation for non-optimized output.
The pass walk through the machine function and assign the register banks
using the default mapping. In other words, there is no attempt to reduce
cross register copies.

llvm-svn: 265707
2016-04-07 18:19:27 +00:00
Quentin Colombet fe1ee4f9be [RegisterBankInfo] Provide a target independent helper function to guess
the mapping of an instruction on register bank.

For most instructions, it is possible to guess the mapping of the
instruciton by using the encoding constraints.
It remains instructions without encoding constraints.
For copy-like instructions, we try to propagate the information we get
from the other operands. Otherwise, the target has to give this
information.

llvm-svn: 265703
2016-04-07 18:01:19 +00:00
Quentin Colombet ee366eff44 [RegisterBankInfo] Change the signature of getSizeInBits to factor out
the access to MRI and TRI.

llvm-svn: 265701
2016-04-07 17:44:54 +00:00
Quentin Colombet 5b7ba5092c [RegisterBankInfo] Provide a default constructor for InstructionMapping
helper class.

The default constructor creates invalid (isValid() == false) instances
and may be used to communicate that a mapping was not found.

llvm-svn: 265699
2016-04-07 17:30:18 +00:00
Quentin Colombet c33085f2c6 [MachineRegisterInfo] Track register bank for virtual registers.
A virtual register may have either a register bank or a register class.
This is represented by a PointerUnion between the related classes.

Typically, a virtual register went through the following states
regarding register class and register bank:

1. Creation: None is set. Virtual registers are fully generic.
2. Register bank assignment: Register bank is set. Virtual registers
live into a register bank, but we do not know the constraints they need
to fulfil.
3. Instruction selection: Register class is set. Virtual registers are
bound by encoding constraints.

To map these states to GlobalISel, the IRTranslator implements #1,
RegBankSelect #2, and Select #3.

llvm-svn: 265696
2016-04-07 17:20:29 +00:00
Quentin Colombet d21115876c [RegisterBank] Rename RegisterBank::contains into RegisterBank::covers.
llvm-svn: 265695
2016-04-07 17:09:39 +00:00
Dmitry Polukhin a1feff7024 [GCC] Attribute ifunc support in llvm
This patch add support for GCC attribute((ifunc("resolver"))) for
targets that use ELF as object file format. In general ifunc is a
special kind of function alias with type @gnu_indirect_function. Patch
for Clang http://reviews.llvm.org/D15524

Differential Revision: http://reviews.llvm.org/D15525

llvm-svn: 265667
2016-04-07 12:32:19 +00:00
NAKAMURA Takumi e546211492 InlineSpiller.cpp: Escap \@ in r265547. [-Wdocumentation]
llvm-svn: 265657
2016-04-07 11:30:06 +00:00
Amaury Sechet 33c161c02f [BlockPlacement] Remove an unnecessary continue
NFC.

llvm-svn: 265643
2016-04-07 06:35:00 +00:00
Amaury Sechet 9ee4ddd710 [MBP] Remove an unused function parameter
NFC.

llvm-svn: 265642
2016-04-07 06:34:47 +00:00
Wei Mi 979e9756ec Fix the sanitizer bootstrap error in r265547.
The iterators of SmallPtrSet SpillsInSubTreeMap[Child].first may be
invalidated when SpillsInSubTreeMap grows. Rearrange the code to
ensure the grow of SpillsInSubTreeMap only happens before getting
the iterators of the SmallPtrSet.

llvm-svn: 265639
2016-04-07 05:27:17 +00:00
Amaury Sechet 41474a52e7 Revert "[BlockPlacement] Remove an unnecessary continue" and "[MBP] Remove an unused function parameter"
llvm-svn: 265638
2016-04-07 04:28:40 +00:00
Duncan P. N. Exon Smith da68cbc4ad IR: RF_IgnoreMissingValues => RF_IgnoreMissingLocals, NFC
Clarify what this RemapFlag actually means.

  - Change the flag name to match its intended behaviour.
  - Clearly document that it's not supposed to affect globals.
  - Add a host of FIXMEs to indicate how to fix the behaviour to match
    the intent of the flag.

RF_IgnoreMissingLocals should only affect the behaviour of
RemapInstruction for function-local operands; namely, for operands of
type Argument, Instruction, and BasicBlock.  Currently, it is *only*
passed into RemapInstruction calls (and the transitive MapValue calls
that it makes).

When I split Metadata from Value I didn't understand the flag, and I
used it in a bunch of places for "global" metadata.

This commit doesn't have any functionality change, but prepares to
cleanup MapMetadata and MapValue.

llvm-svn: 265628
2016-04-07 00:26:43 +00:00
Quentin Colombet 4359784c1b [RegisterBankInfo] Implement a target independent version of
getInstrMapping.

This implementation requires that the target implemented
getRegBankFromRegClass.
Indeed, the implementation uses the register classes for the encoding
constraints for the instructions to deduce the mapping of a value.

llvm-svn: 265624
2016-04-07 00:07:50 +00:00
Quentin Colombet 8c0d66bc54 [RegisterBankInfo] Add an helper function to get the size of a register.
The previous method to get the size was too simple and could fail for
physical registers.

llvm-svn: 265620
2016-04-06 23:59:53 +00:00
Wei Mi 284fa0bd71 Fix the compare-clang diff error introduced by r265547.
Use MapVector instead of DenseMap for MergeableSpillsMap so it will be
iterated in determined order.

llvm-svn: 265610
2016-04-06 22:31:17 +00:00
Quentin Colombet c916204a81 [RegisterBankInfo] Add methods to get the possible mapping of an instruction on a register bank.
This will be used by the register bank select pass to assign register banks
for generic virtual registers.

This was originally committed as r265573 but broke at least one windows bot.
The problem with the windows bot was that it was using a copy constructor for
the InstructionMappings class and could not synthesize it. Actually, the fact
that this class is not copy constructable is expected and the compiler should
use the move assignment constructor. Marking the problematic assignment
explicitly as using the move constructor has its own problems.

Indeed, with recent clang we get a warning that we may prevent the elision of
the copy by the compiler. A proper fix for both compilers would be to change the
API of getPossibleInstrMapping to take a InstructionMappings as input/output
parameter. This does not feel natural and since GISel is not used on windows
yet, I chose to workaround the problem by not compiling the problematic code on
windows.

llvm-svn: 265604
2016-04-06 21:37:22 +00:00
JF Bastien 800f87a871 NFC: make AtomicOrdering an enum class
Summary:
In the context of http://wg21.link/lwg2445 C++ uses the concept of
'stronger' ordering but doesn't define it properly. This should be fixed
in C++17 barring a small question that's still open.

The code currently plays fast and loose with the AtomicOrdering
enum. Using an enum class is one step towards tightening things. I later
also want to tighten related enums, such as clang's
AtomicOrderingKind (which should be shared with LLVM as a 'C++ ABI'
enum).

This change touches a few lines of code which can be improved later, I'd
like to keep it as NFC for now as it's already quite complex. I have
related changes for clang.

As a follow-up I'll add:
  bool operator<(AtomicOrdering, AtomicOrdering) = delete;
  bool operator>(AtomicOrdering, AtomicOrdering) = delete;
  bool operator<=(AtomicOrdering, AtomicOrdering) = delete;
  bool operator>=(AtomicOrdering, AtomicOrdering) = delete;
This is separate so that clang and LLVM changes don't need to be in sync.

Reviewers: jyknight, reames

Subscribers: jyknight, llvm-commits

Differential Revision: http://reviews.llvm.org/D18775

llvm-svn: 265602
2016-04-06 21:19:33 +00:00
Haicheng Wu 1951cf24a7 [MBP] Remove an unused function parameter
NFC.

llvm-svn: 265596
2016-04-06 20:38:20 +00:00
Quentin Colombet fb000583aa Revert "[RegisterBankInfo] Add methods to get the possible mapping of an
instruction on a register bank. This will be used by the register bank select
pass to assign register banks for generic virtual registers." and the follow-on
commits while I find out a way to fix the win7 bot:
http://lab.llvm.org:8011/builders/sanitizer-windows/builds/19882

This reverts commit r265578, r265581, r265584, and r265585.

llvm-svn: 265587
2016-04-06 19:04:58 +00:00
Evgeniy Stepanov 268826a287 [gold] Save bitcode for module partitions (save-temps + split codegen).
llvm-svn: 265583
2016-04-06 18:32:13 +00:00
Quentin Colombet df4aee09f8 [RegisterBankInfo] Provide a default constructor for InstructionMapping
helper class.

The default constructor creates invalid (isValid() == false) instances
and may be used to communicate that a mapping was not found.

llvm-svn: 265581
2016-04-06 18:24:34 +00:00
Quentin Colombet bb756dbf39 [RegisterBankInfo] Add an helper function to get the size of a register.
The previous method to get the size was too simple and could fail for
physical registers.

llvm-svn: 265578
2016-04-06 18:04:35 +00:00
Quentin Colombet 9af77135e5 [RegisterBankInfo] Add methods to get the possible mapping of an instruction on a register bank.
This will be used by the register bank select pass to assign register banks
for generic virtual registers.

llvm-svn: 265573
2016-04-06 17:45:40 +00:00
Quentin Colombet 4812c91f56 [RegisterBankInfo] Implement the verify method of the InstructionMapping helper class.
This checks that all the register operands get a proper mapping.

llvm-svn: 265563
2016-04-06 17:01:43 +00:00
Quentin Colombet 3768f7005d [RegisterBankInfo] Implement the verify method for the ValueMapping helper class.
The method checks that the value is fully defined accross the different partial
mappings and that the partial mappings are compatible between each other.

llvm-svn: 265556
2016-04-06 16:40:23 +00:00
Quentin Colombet 2423fc419c [RegisterBankInfo] Add a verify method for the PartialMapping helper class.
This verifies that the PartialMapping can be accomadated into the related
register bank.

llvm-svn: 265555
2016-04-06 16:33:26 +00:00
Quentin Colombet 89c33caee3 [RegisterBankInfo] Add a couple of helper classes for the future cost model.
llvm-svn: 265553
2016-04-06 16:27:01 +00:00
Quentin Colombet 911181882e [RegisterBankInfo] Inline the destructor to avoid link-time error when GlobalISel is not built.
llvm-svn: 265548
2016-04-06 15:47:17 +00:00
Wei Mi 18293bef4e Recommit r265309 after fixed an invalid memory reference bug happened
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
2016-04-06 15:41:07 +00:00
Matthias Braun 7dc03f060e RegisterScavenger: Take a reference as enterBasicBlock() argument.
Make it obvious that the argument cannot be nullptr.
Remove an unnecessary nullptr check in initRegState.

llvm-svn: 265511
2016-04-06 02:47:09 +00:00
Matthias Braun 3bb0fcc118 LivePhysRegs: Remove redundant check
llvm-svn: 265509
2016-04-06 02:46:04 +00:00
Sanjoy Das 65a60670e8 Lower @llvm.experimental.deoptimize as a noreturn call
While preserving the return value for @llvm.experimental.deoptimize at
the IR level is useful during mid-level optimization, doing so at the
machine instruction level requires generating some extra code and a
return that is non-ideal.  This change has LLVM lower

```
  %val = call @llvm.experimental.deoptimize
  ret %val
```

to effectively

```
  call @__llvm_deoptimize()
  unreachable
```

instead.

llvm-svn: 265502
2016-04-06 01:33:49 +00:00
Quentin Colombet 06bdd3c914 [RegisterBankInfo] Simplify the API for build a register bank.
As part of the TRI argument of addRegBankCoverage we already have access to
the TargetRegisterClass through the ID of that register class.
Therefore, there is no point in needing a TargetRegisterClass instance,
the ID is enough to get to it.

llvm-svn: 265487
2016-04-05 23:26:39 +00:00
Evgeniy Stepanov dde29e2799 Faster stack-protector for Android/AArch64.
Bionic has a defined thread-local location for the stack protector
cookie. Emit a direct load instead of going through __stack_chk_guard.

llvm-svn: 265481
2016-04-05 22:41:50 +00:00
Quentin Colombet 64bba01a63 [RegisterBank] Implement the verify method to check for the obvious mistakes.
llvm-svn: 265479
2016-04-05 22:34:01 +00:00
Quentin Colombet 0195826998 [RegisterBankInfo] Add debug print to check how the initialization is going.
llvm-svn: 265475
2016-04-05 21:47:56 +00:00
Quentin Colombet c94fbee9f6 [RegisterBank] Add printable capabilities for future debugging.
llvm-svn: 265473
2016-04-05 21:40:43 +00:00
Quentin Colombet 85689d934a [RegisterBankInfo] Make addRegBankCoverage more capable to ease
targeting jobs.
Now, addRegBankCoverage also adds the subreg-classes not just the
sub-classes of the given register class.

llvm-svn: 265469
2016-04-05 21:20:12 +00:00
Quentin Colombet d347d695c2 [RegisterBankInfo] Implement the methods to create register banks.
llvm-svn: 265464
2016-04-05 21:06:15 +00:00
Quentin Colombet c4db2ad5b8 [RegisterBank] Provide a way to check if a register bank is valid.
Change the default constructor to create invalid object.
The target will have to properly initialize the register banks before
using them.

llvm-svn: 265460
2016-04-05 20:48:32 +00:00
Quentin Colombet b235d32e74 [GlobalISel] Add the RegisterBankInfo class for the handling of register banks.
llvm-svn: 265449
2016-04-05 20:02:47 +00:00
Quentin Colombet bdc3b4d523 [GlobalISel] Add a class, RegisterBank, to represent register banks.
llvm-svn: 265445
2016-04-05 19:54:44 +00:00
Quentin Colombet 8e8e85c19f [GlobalISel] Add the skeleton of the RegBankSelect pass.
This pass is reponsible for assigning the generic virtual registers to register
banks.

llvm-svn: 265440
2016-04-05 19:06:01 +00:00
Manman Ren e221a870d3 Swift Calling Convention: swifterror target-independent change.
At IR level, the swifterror argument is an input argument with type
ErrorObject**. For targets that support swifterror, we want to optimize it
to behave as an inout value with type ErrorObject*; it will be passed in a
fixed physical register.

The main idea is to track the virtual registers for each swifterror value. We
define swifterror values as AllocaInsts with swifterror attribute or a function
argument with swifterror attribute.

In SelectionDAGISel.cpp, we set up swifterror values (SwiftErrorVals) before
handling the basic blocks.

When iterating over all basic blocks in RPO, before actually visiting the basic
block, we call mergeIncomingSwiftErrors to merge incoming swifterror values when
there are multiple predecessors or to simply propagate them. There, we create a
virtual register for each swifterror value in the entry block. For predecessors
that are not yet visited, we create virtual registers to hold the swifterror
values at the end of the predecessor. The assignments are saved in
SwiftErrorWorklist and will be materialized at the end of visiting the basic
block.

When visiting a load from a swifterror value, we copy from the current virtual
register assignment. When visiting a store to a swifterror value, we create a
virtual register to hold the swifterror value and update SwiftErrorMap to
track the current virtual register assignment.

Differential Revision: http://reviews.llvm.org/D18108

llvm-svn: 265433
2016-04-05 18:13:16 +00:00
Haicheng Wu 3618fa786f [BlockPlacement] Remove an unnecessary continue
NFC.

llvm-svn: 265407
2016-04-05 15:37:08 +00:00
Chuang-Yu Cheng d3fb38cae5 Don't delete empty preheaders in CodeGenPrepare if it would create a critical edge
Presently, CodeGenPrepare deletes all nearly empty (only phi and branch)
basic blocks. This pass can delete loop preheaders which frequently creates
critical edges. A preheader can be a convenient place to spill registers to
the stack. If the entrance to a loop body is a critical edge, then spills
may occur in the loop body rather than immediately before it. This patch
protects loop preheaders from deletion in CodeGenPrepare even if they are
nearly empty.

Since the patch alters the CFG, it affects a large number of test cases.
In most cases, the changes are merely cosmetic (basic blocks have different
names or instruction orders change slightly). I am somewhat concerned about
the test/CodeGen/Mips/brdelayslot.ll test case. If the loop preheader is not
deleted, then the MIPS backend does not take advantage of a branch delay
slot. Consequently, I would like some close review by a MIPS expert.

The patch also partially subsumes D16893 from George Burgess IV. George
correctly notes that CodeGenPrepare does not actually preserve the dominator
tree. I think the dominator tree was usually not valid when CodeGenPrepare
ran, but I am using LoopInfo to mark preheaders, so the dominator tree is
now always valid before CodeGenPrepare.

Author: Tom Jablin (tjablin)
Reviewers: hfinkel george.burgess.iv vkalintiris dsanders kbarton cycheng

http://reviews.llvm.org/D16984

llvm-svn: 265397
2016-04-05 14:06:20 +00:00
Dmitry Polukhin a3d5b0b218 [IFUNC] Use GlobalIndirectSymbol when aliases and ifuncs have something similar
Second part extracted from http://reviews.llvm.org/D15525

Use GlobalIndirectSymbol in all cases when aliases and ifuncs have
something in common.

Differential Revision: http://reviews.llvm.org/D18754

llvm-svn: 265382
2016-04-05 08:47:51 +00:00
Sanjay Patel 769b5fd546 fix typos; NFC
llvm-svn: 265356
2016-04-04 22:45:56 +00:00
Justin Bogner 35c6903f22 Revert "CodeGen: Remove dead code in TailDuplicate"
It seems this is reachable after all. It hit on 7zip-benchmark in lnt
on ppc64:

  http://lab.llvm.org:8011/builders/clang-ppc64be-linux-lnt/builds/2317

This reverts r265347.

llvm-svn: 265352
2016-04-04 21:41:54 +00:00
Matthias Braun 7511abd5c1 MachineScheduler: Ignore COPYs with undef/dead op in CopyConstrain mutation.
There is no problem with the code today, but the fix will avoid a crash
in test/CodeGen/AMDGPU/subreg-coalescer-undef-use.ll once the
DetectDeadLanes pass is added.

llvm-svn: 265351
2016-04-04 21:23:46 +00:00
Justin Bogner 9ab8131a57 CodeGen: Remove dead code in TailDuplicate
I noticed that this isn't covered by our existing tests and spent some
time trying to come up with an example it actually hits. I tried hand
rolling something based on the explanation in the comment, but couldn't
get anything that didn't abort tail duplication earlier for one reason
or another.

Then, I tried cranking tail-dup-size cranked up so this would fire
more and ran a bootstrap of clang and the nightly test suite - those
don't hit this either.

This reverts r132816 and replaces it with an assert.

llvm-svn: 265347
2016-04-04 21:11:40 +00:00
Chandler Carruth 613eec8210 Revert r263460: [SpillPlacement] Fix a quadratic behavior in spill placement.
That commit looks wonderful and awesome. Sadly, it greatly exacerbates
PR17409 and effectively regresses build time for a lot of (very large)
code when compiled with ASan or MSan.

We thought this could be fixed forward by landing D15302 which at last
fixes that PR, but some issues were discovered and it looks like that
got reverted, so reverting this as well temporarily. As soon as the fix
for PR17409 lands and sticks, we should re-land this patch as it won't
trigger more significant test cases hitting that bug.

Many thanks to Quentin and Wei here as they're doing all the awesome
hard work!!!

llvm-svn: 265331
2016-04-04 18:57:50 +00:00
Matthias Braun 870c34f0cf ARM, AArch64, X86: Check preserved registers for tail calls.
We can only perform a tail call to a callee that preserves all the
registers that the caller needs to preserve.

This situation happens with calling conventions like preserver_mostcc or
cxx_fast_tls. It was explicitely handled for fast_tls and failing for
preserve_most. This patch generalizes the check to any calling
convention.

Related to rdar://24207743

Differential Revision: http://reviews.llvm.org/D18680

llvm-svn: 265329
2016-04-04 18:56:13 +00:00
Derek Schuff 73900c6876 Replace MachineRegisterInfo::isSSA() with a MachineFunctionProperty
Use the MachineFunctionProperty mechanism to indicate whether a MachineFunction
is in SSA form instead of a custom method on MachineRegisterInfo. NFC

Differential Revision: http://reviews.llvm.org/D18574

llvm-svn: 265318
2016-04-04 18:03:29 +00:00
Wei Mi fb5252cac1 Revert r265309 and r265312 because they caused some errors I need to investigate.
llvm-svn: 265317
2016-04-04 17:45:03 +00:00
Derek Schuff 1dbf7a571f Add MachineFunctionProperty checks for AllVRegsAllocated for target passes
Summary:
This adds the same checks that were added in r264593 to all
target-specific passes that run after register allocation.

Reviewers: qcolombet

Subscribers: jyknight, dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D18525

llvm-svn: 265313
2016-04-04 17:09:25 +00:00
Wei Mi cdaf1df657 Fix unused var warning caused by r265309.
llvm-svn: 265312
2016-04-04 17:03:58 +00:00
Wei Mi ffbc9c7f3b 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: 265309
2016-04-04 16:42:40 +00:00
Peter Zotov 8efe38a1e2 [CodeGenPrepare] Fix r265264 (again).
Don't require TLI for SinkCmpExpression, like it wasn't before
r265264.

llvm-svn: 265271
2016-04-03 19:32:13 +00:00
Peter Zotov f87e550e89 [CodeGenPrepare] Fix r265264.
The case where there was no TargetLowering was not handled,
leading to null pointer dereferences.

llvm-svn: 265265
2016-04-03 17:11:53 +00:00
Peter Zotov 0b6d7bc682 [CodeGenPrepare] Avoid sinking soft-FP comparisons
Sinking comparisons in CGP can undo the job of hoisting them done
earlier by LICM, and soft-FP makes this an expensive mistake.

A common pattern that produces floating point comparisons uniform
over a loop is an explicit check for division by zero. If the divisor
is hoisted out of the loop, the comparison can also be, but hoisting
the function that unwinds is never legal, since it may cause side
effects in the loop body prior to the unwinding to not be executed.

Differential Revision: http://reviews.llvm.org/D18744

llvm-svn: 265264
2016-04-03 16:36:17 +00:00
Manman Ren 9bfd0d03e9 Swift Calling Convention: add swifterror attribute.
A ``swifterror`` attribute can be applied to a function parameter or an
AllocaInst.

This commit does not include any target-specific change. The target-specific
optimization will come as a follow-up patch.

Differential Revision: http://reviews.llvm.org/D18092

llvm-svn: 265189
2016-04-01 21:41:15 +00:00
Sanjoy Das 9d41a8f269 Don't use an i64 return type with webkit_jscc
Re-enable an assertion enabled by Justin Lebar in rL265092.  rL265092
was breaking test/CodeGen/X86/deopt-intrinsic.ll because webkit_jscc
does not like non-i64 return types.  Change the test case to not do
that.

llvm-svn: 265099
2016-04-01 02:51:21 +00:00
Chuang-Yu Cheng 35c6181982 Fix Sub-register Rewriting in Aggressive Anti-Dependence Breaker
Previously, HandleLastUse would delete RegRef information for sub-registers
if they were dead even if their corresponding super-register were still live.

If the super-register were later renamed, then the definitions of the
sub-register would not be updated appropriately. This patch alters the
behavior so that RegInfo information for sub-registers is only deleted when
the sub-register and super-register are both dead.

This resolves PR26775. This is the mirror image of Hal's r227311 commit.

Author: Tom Jablin (tjablin)
Reviewers: kbarton uweigand nemanjai hfinkel

http://reviews.llvm.org/D18448

llvm-svn: 265097
2016-04-01 02:05:29 +00:00
Justin Lebar 98981e5573 Revert "Protect some assertions with NDEBUG rather than DEBUG()."
This reverts r265092, because it breaks CodeGen/X86/deopt-intrinsic.ll.

llvm-svn: 265093
2016-04-01 01:23:23 +00:00
Justin Lebar c814e8e4ab Protect some assertions with NDEBUG rather than DEBUG().
DEBUG() only runs if you pass -debug, but these assertions are generally
useful.

llvm-svn: 265092
2016-04-01 01:09:12 +00:00
Justin Lebar acc47105f8 [ifcnv] Add brief comment explaining what ifcnv is.
llvm-svn: 265088
2016-04-01 01:09:03 +00:00
Adrian Prantl b939a25707 Move the DebugEmissionKind enum from DIBuilder into DICompileUnit.
This mostly cosmetic patch moves the DebugEmissionKind enum from DIBuilder
into DICompileUnit. DIBuilder is not the right place for this enum to live
in — a metadata consumer should not have to include DIBuilder.h.
I also added a Verifier check that checks that the emission kind of a
DICompileUnit is actually legal.

http://reviews.llvm.org/D18612
<rdar://problem/25427165>

llvm-svn: 265077
2016-03-31 23:56:58 +00:00
Tim Shen 800ed436e5 [AsmPrinter] Print aliases in topological order
Print aliases in topological order, that is, for any alias a = b,
b must be printed before a. This is because on some targets (e.g. PowerPC)
linker expects aliases in such an order to generate correct TOC information.

GCC also prints aliases in topological order.

llvm-svn: 265064
2016-03-31 22:08:19 +00:00
Chandler Carruth b472856a73 Fix PR26940 where compiles times regressed massively.
Patch by Jonas Paulsson. Original description:
Bugfix in buildSchedGraph() to make -dag-maps-huge-region work properly

I found that the reduction of the maps did in fact never happen in this
test case. This was because *all* the stores / loads were made with
addresses from arguments and they thus became "unknown" stores / loads.
Fixed by removing continue statements and making sure that the test for
reduction always takes place.

Differential Revision: http://reviews.llvm.org/D18673

llvm-svn: 265063
2016-03-31 21:55:58 +00:00
Sanjay Patel 4d71160d5d fix typo; NFC
llvm-svn: 265054
2016-03-31 21:00:48 +00:00
Hans Wennborg e1a2e90ffa Change eliminateCallFramePseudoInstr() to return an iterator
This will become necessary in a subsequent change to make this method
merge adjacent stack adjustments, i.e. it might erase the previous
and/or next instruction.

It also greatly simplifies the calls to this function from Prolog-
EpilogInserter. Previously, that had a bunch of logic to resume iteration
after the call; now it just continues with the returned iterator.

Note that this changes the behaviour of PEI a little. Previously,
it attempted to re-visit the new instruction created by
eliminateCallFramePseudoInstr(). That code was added in r36625,
but I can't see any reason for it: the new instructions will obviously
not be pseudo instructions, they will not have FrameIndex operands,
and we have already accounted for the stack adjustment.

Differential Revision: http://reviews.llvm.org/D18627

llvm-svn: 265036
2016-03-31 18:33:38 +00:00
Stephan Bergmann 480de227f6 Don't use potentially invalidated iterator
If the lhs is evaluated before the rhs, FuncletI's operator-> can trigger the

  assert(isHandleInSync() && "invalid iterator access!");

at include/llvm/ADT/DenseMap.h:1061.  (Happens e.g. when compiled with GCC 6.)

Differential Revision: http://reviews.llvm.org/D18440

llvm-svn: 265024
2016-03-31 15:42:01 +00:00
Nirav Dave 83ce54aac2 Prevent X86ISelLowering from merging volatile loads
Change isConsecutiveLoads to check that loads are non-volatile as this
is a requirement for any load merges. Propagate change to two callers.

Reviewers: RKSimon

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18546

llvm-svn: 265013
2016-03-31 13:40:55 +00:00
Matthias Braun 8d41436004 CodeGen: Factor out code for tail call result compatibility check; NFC
llvm-svn: 264959
2016-03-30 22:46:04 +00:00
Matt Arsenault 46ba31650e LegalizeDAG: Don't replace vector store with integer if not legal
For the same reason as the corresponding load change.

Note that ExpandStore is completely broken for non-byte sized element
vector stores, but preserve the current broken behavior which has tests
for it. The behavior should be the same, but now introduces a new typed
store that is incorrectly split later rather than doing it directly.

llvm-svn: 264928
2016-03-30 21:15:18 +00:00
Matt Arsenault a4b1b6ea05 LegalizeDAG: Don't replace vector load with integer unless legal
On AMDGPU we want to be able to promote i64/f64 loads to v2i32.
If the access is unaligned, this would conclude that since i64 is legal,
it would convert it back to i64 and there is an endless legalization
loop.

Extract the logic for scalarizing the load into a new TargetLowering
function, where this can also replace the custom function AMDGPU
has for this.

llvm-svn: 264927
2016-03-30 21:15:10 +00:00
Fiona Glaser 44a2f7a298 MachineSink: make shouldSink a TII target hook
Some targets may disagree on what they want sunk or not sunk,
so make this a target hook instead of hardcoded.

llvm-svn: 264799
2016-03-29 22:44:57 +00:00
Derek Schuff 07636cd5e7 Add a print method to MachineFunctionProperties for better error messages
This makes check failures much easier to understand.
Make it empty (but leave it in the class) for NDEBUG builds.

Differential Revision: http://reviews.llvm.org/D18529

llvm-svn: 264780
2016-03-29 20:28:20 +00:00
Matthias Braun 72a58c3e28 MachineVerifier: On dead-def live segments, check that corresponding machine operand has a dead flag
llvm-svn: 264769
2016-03-29 19:07:43 +00:00
Matthias Braun 1c20c8280a LiveVariables: Fix typo and shorten comment
llvm-svn: 264768
2016-03-29 19:07:40 +00:00
Nirav Dave 2aab7f4358 Add support for no-jump-tables
Add function soft attribute to the generation of Jump Tables in CodeGen
as initial step towards clang support of gcc's no-jump-table support

Reviewers: hans, echristo

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18321

llvm-svn: 264756
2016-03-29 17:46:23 +00:00
Derek Schuff 42666eeea2 Add MachineVerifier check for AllVRegsAllocated MachineFunctionProperty
Summary:
Check that any function that has the property set is free of virtual
register operands.

Also, it is actually VirtRegMap (and not the register allocators) that
acutally remove the VReg operands (except for RegAllocFast).

Reviewers: qcolombet

Subscribers: MatzeB, llvm-commits, qcolombet

Differential Revision: http://reviews.llvm.org/D18535

llvm-svn: 264755
2016-03-29 17:40:22 +00:00
Manman Ren f46262e0b7 Swift Calling Convention: add swiftself attribute.
Differential Revision: http://reviews.llvm.org/D17866

llvm-svn: 264754
2016-03-29 17:37:21 +00:00
Matthias Braun f54530ef00 RegisterPressure: Simplify liveness tracking when lanemasks are not checked.
Split RegisterOperands code that collects defs/uses into a variant with
and without lanemask tracking. This is a bit of code duplication, but
there are enough subtle differences between the two variants that this
seems cleaner (and potentially faster).

This also fixes a problem where lanes where tracked even though
TrackLaneMasks was false. This is part of the fix for
http://llvm.org/PR27106. I will commit the testcase when it is
completely fixed.

llvm-svn: 264696
2016-03-29 03:54:22 +00:00
Matthias Braun 82cff88691 LiveVariables: Do not remove dead flags from vreg operands
Also add a FIXME comment on why Mips RDDSP causes bogus dead flags to be
added which LiveVariables cleans up by accident.

llvm-svn: 264695
2016-03-29 03:08:18 +00:00
Kyle Butt 5e241b11ed [Codegen] Decrease minimum jump table density.
Minimum density for both optsize and non optsize are now options
-sparse-jump-table-density (default 10) for non optsize functions
-dense-jump-table-density (default 40) for optsize functions, which
matches the current default. This improves several benchmarks at google
at the cost of a small codesize increase. For code compiled with -Os,
the old behavior continues

llvm-svn: 264689
2016-03-29 00:23:41 +00:00
Matthias Braun b74eb41d58 MIRParser: Add %subreg.xxx syntax for subregister index operands
Differential Revision: http://reviews.llvm.org/D18279

llvm-svn: 264608
2016-03-28 18:18:46 +00:00
Derek Schuff ad154c837e Introduce MachineFunctionProperties and the AllVRegsAllocated property
MachineFunctionProperties represents a set of properties that a MachineFunction
can have at particular points in time. Existing examples of this idea are
MachineRegisterInfo::isSSA() and MachineRegisterInfo::tracksLiveness() which
will eventually be switched to use this mechanism.
This change introduces the AllVRegsAllocated property; i.e. the property that
all virtual registers have been allocated and there are no VReg operands
left.

With this mechanism, passes can declare that they require a particular property
to be set, or that they set or clear properties by implementing e.g.
MachineFunctionPass::getRequiredProperties(). The MachineFunctionPass base class
verifies that the requirements are met, and handles the setting and clearing
based on the delcarations. Passes can also directly query and update the current
properties of the MF if they want to have conditional behavior.

This change annotates the target-independent post-regalloc passes; future
changes will also annotate target-specific ones.

Reviewers: qcolombet, hfinkel

Differential Revision: http://reviews.llvm.org/D18421

llvm-svn: 264593
2016-03-28 17:05:30 +00:00
James Y Knight 01f2ca5612 NFC: skip FenceInst up-front in AtomicExpandPass.
llvm-svn: 264583
2016-03-28 15:05:30 +00:00
JF Bastien a874d1a40d Revert "NFC: static_assert instead of comment"
This reverts commit fa36fcff16c7d4f78204d6296bf96c3558a4a672.

Causes the following Windows failure:

  C:\Buildbot\Slave\llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast\llvm.src\lib\CodeGen\MachineInstr.cpp(762):
  error C2338: must be trivially copyable to memmove

llvm-svn: 264516
2016-03-26 18:20:02 +00:00
JF Bastien d4ff3360ae NFC: static_assert instead of comment
Summary: isPodLike is as close as we have for is_trivially_copyable.

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18483

llvm-svn: 264515
2016-03-26 18:14:27 +00:00
Junmo Park a26e93bcec Minor code cleanup. NFC.
llvm-svn: 264505
2016-03-26 06:04:55 +00:00
Jun Bum Lim 36c53fe147 [MachineCopyPropagation] Expose more dead copies across instructions with regmasks
When encountering instructions with regmasks, instead of cleaning up all the
elements in MaybeDeadCopies map, remove only the instructions erased. By keeping
more instruction in MaybeDeadCopies, this change will expose more dead copies
across instructions with regmasks.

llvm-svn: 264462
2016-03-25 21:15:35 +00:00
Nirav Dave fa250cad37 Prevent construction of cycle in DAG store merge
When merging stores in DAGCombiner, add check to ensure that no
dependenices exist that would cause the construction of a cycle in our
DAG.  This may happen if one store has a data dependence on another
instruction (e.g. a load) which itself has a (chain) dependence on
another store being merged. These stores cannot be merged safely and
doing so results in a cycle that is discovered in LegalizeDAG.

This test is only done in cases where Antialias analysis is used (UseAA)
as non-AA store merge candidates will be merged logically after all
loads which have been checked to not alias.

Reviewers: ahatanak, spatel, niravd, arsenm, hfinkel, tstellarAMD, jyknight

Subscribers: llvm-commits, tberghammer, danalbert, srhines

Differential Revision: http://reviews.llvm.org/D18336

llvm-svn: 264461
2016-03-25 21:06:30 +00:00
Justin Bogner ec0e7d2582 CodeGen: Don't iterate over operands after we've erased an MI
This fixes a use-after-free introduced 3 years ago, in r182872 ;)

The code more or less worked because the memory that CopyMI was
pointing to happened to still be valid, but lots of tests would crash
if you ran under ASAN with the recycling allocator changes from
llvm.org/PR26808

llvm-svn: 264455
2016-03-25 20:03:28 +00:00
Justin Bogner ec5ea36891 CodeGen: Fix a use-after-free in TII
Found by ASAN with the recycling allocator changes from PR26808.

llvm-svn: 264443
2016-03-25 18:38:48 +00:00
Reid Kleckner f6f04f8fc8 Consider regmasks when computing register-based DBG_VALUE live ranges
Now register parameters that aren't saved to the stack or CSRs are
considered dead after the first call. Previously the debugger would show
whatever was in the register.

Fixes PR26589

Reviewers: aprantl

Differential Revision: http://reviews.llvm.org/D17211

llvm-svn: 264429
2016-03-25 17:54:46 +00:00
Manman Ren 9dd8c14674 CXX TLS: collect return blocks after SelectAllBasicBlocks.
It is incorrect to get the corresponding MBB for a ReturnInst before
SelectAllBasicBlocks since SelectAllBasicBlocks can change the
correspondence between a ReturnInst and the MBB it is in.

PR27062

llvm-svn: 264358
2016-03-24 23:21:29 +00:00
Sanjoy Das fd3eaa8c5c Reduce code duplication by extracting out a helper function; NFC
llvm-svn: 264355
2016-03-24 22:51:49 +00:00
Sanjoy Das 731c67fed2 Lower varargs correctly in deopt bundle lowering
Earlier we were ignoring varargs in LowerCallSiteWithDeoptBundle because
populateCallLoweringInfo does not set CallLoweringInfo::IsVarArg.

llvm-svn: 264354
2016-03-24 22:37:52 +00:00
Matthias Braun ae81c29352 LiveInterval: Fix Distribute() failing on liveranges with unused VNInfos
This fixes http://llvm.org/PR26991

llvm-svn: 264345
2016-03-24 21:41:38 +00:00
Reid Kleckner 01bc66a8ce Revert "Recommitted r263424 "Supporting all entities declared in lexical scope in LLVM debug info." After fixing PR26942 (the fix is included in this commit)."
This reverts commit r264280.

This broke building Chromium for iOS. We'll upload a reproducer to the
PR soon.

llvm-svn: 264334
2016-03-24 20:38:49 +00:00
Sanjoy Das df9ae70f49 Add lowering support for llvm.experimental.deoptimize
Summary:
Only adds support for "naked" calls to llvm.experimental.deoptimize.
Support for round-tripping through RewriteStatepointsForGC will come
as a separate patch (should be simpler than this one).

Reviewers: reames

Subscribers: sanjoy, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D18429

llvm-svn: 264329
2016-03-24 20:23:29 +00:00
Sanjoy Das c0c59fe14e [Statepoints] Fix yet another issue around gc pointer uniqueing
Given that StatepointLowering now uniques derived pointers before
putting them in the per-statepoint spill map, we may end up with missing
entries for derived pointers when we visit a gc.relocate on a pointer
that was de-duplicated away.

Fix this by keeping two maps, one mapping gc pointers to their
de-duplicated values, and one mapping a de-duplicated value to the slot
it is spilled in.

llvm-svn: 264320
2016-03-24 18:57:39 +00:00
Sanjoy Das 42f91a9959 Minor cosmestic changes (NFC)
- Reflow comments
 - Rename function

llvm-svn: 264319
2016-03-24 18:57:31 +00:00
David Blaikie 0b214e4a2a [debuginfo] Include dwo_name in the split unit to improve dwp diagnostics
When multiple DWP files are merged together and duplicate DWO IDs are
found it's currently difficult to give an actionable error message - the
DW_AT_name of the CU could be provided, but might be identical (if the
same source file is built into two different configurations), which
doesn't help the user identify the problem.

When no intermediate DWP files are generated, the path to the two DWO
files could be provided - but is lost once the DWOs are merged into a
DWP.

So, include the name of the DWO (dwo_name) in the split file so that
collissions involving a source CU from a DWP can be better diagnosed.

(improvements to llvm-dwp using this to come shortly)

llvm-svn: 264316
2016-03-24 18:37:08 +00:00
Tim Northover 4498eff9bb CodeGen: extend RHS when splitting ATOMIC_CMP_SWAP_WITH_SUCCESS.
If the operation's type has been promoted during type legalization, we
need to account for the fact that the high bits of the comparison
operand are likely unspecified.

The LHS is usually zero-extended, but MIPS sign extends it, so we have
to be slightly careful.

Patch by Simon Dardis.

llvm-svn: 264296
2016-03-24 15:38:38 +00:00
Pirama Arumuga Nainar dc45aef2d8 Remove unsafe AssertZext after promoting result of FP_TO_FP16
Summary:
Some target lowerings of FP_TO_FP16, for instance ARM's vcvtb.f16.f32
instruction, do not guarantee that the top 16 bits are zeroed out.
Remove the unsafe AssertZext and add tests to exercise this.

Reviewers: jmolloy, sbaranga, kristof.beyls, aadg

Subscribers: llvm-commits, srhines, aemerson

Differential Revision: http://reviews.llvm.org/D18426

llvm-svn: 264285
2016-03-24 14:06:03 +00:00
Amjad Aboud 6ff7e10052 Recommitted r263424 "Supporting all entities declared in lexical scope in LLVM debug info."
After fixing PR26942 (the fix is included in this commit).

Differential Revision: http://reviews.llvm.org/D18350

llvm-svn: 264280
2016-03-24 13:30:16 +00:00
Cong Hou 94710840fb Allow X86::COND_NE_OR_P and X86::COND_NP_OR_E to be reversed.
Currently, AnalyzeBranch() fails non-equality comparison between floating points
on X86 (see https://llvm.org/bugs/show_bug.cgi?id=23875). This is because this
function can modify the branch by reversing the conditional jump and removing
unconditional jump if there is a proper fall-through. However, in the case of
non-equality comparison between floating points, this can turn the branch
"unanalyzable". Consider the following case:

jne.BB1
jp.BB1
jmp.BB2
.BB1:
...
.BB2:
...

AnalyzeBranch() will reverse "jp .BB1" to "jnp .BB2" and then "jmp .BB2" will be
removed:

jne.BB1
jnp.BB2
.BB1:
...
.BB2:
...

However, AnalyzeBranch() cannot analyze this branch anymore as there are two
conditional jumps with different targets. This may disable some optimizations
like block-placement: in this case the fall-through behavior is enforced even if
the fall-through block is very cold, which is suboptimal.

Actually this optimization is also done in block-placement pass, which means we
can remove this optimization from AnalyzeBranch(). However, currently
X86::COND_NE_OR_P and X86::COND_NP_OR_E are not reversible: there is no defined
negation conditions for them.

In order to reverse them, this patch defines two new CondCode X86::COND_E_AND_NP
and X86::COND_P_AND_NE. It also defines how to synthesize instructions for them.
Here only the second conditional jump is reversed. This is valid as we only need
them to do this "unconditional jump removal" optimization.


Differential Revision: http://reviews.llvm.org/D11393

llvm-svn: 264199
2016-03-23 21:45:37 +00:00
Justin Bogner c35c10593b SelectionDAG: Remove a tautological dyn_cast. NFC
Index is already a StoreSDNode, so this dyn_cast doesn't do anything.

llvm-svn: 264177
2016-03-23 18:15:33 +00:00
Sanjoy Das a5b2972977 Remove stale comment
llvm-svn: 264131
2016-03-23 02:28:35 +00:00
Sanjoy Das ac53dc7520 [StatepointLowering] Don't do two DenseMap lookups; nfci
llvm-svn: 264130
2016-03-23 02:24:15 +00:00
Sanjoy Das 7edbef316b [StatepointLowering] Minor NFC cleanups
- Use auto
 - Name variables in LLVM style
 - Use llvm::find instead of std::find
 - Blank lines between declarations

llvm-svn: 264129
2016-03-23 02:24:13 +00:00
Sanjoy Das 4cd746ebe0 [StatepointLowering] Minor nfc refactoring
Now that StatepointLoweringInfo represents base pointers, derived
pointers and gc relocates as SmallVectors and not ArrayRefs, we no
longer need to allocate "backing storage" on stack in LowerStatepoint.
So elide the backing storage, and inline the trivial body of
getIncomingStatepointGCValues.

llvm-svn: 264128
2016-03-23 02:24:10 +00:00
Sanjoy Das e58ca59cf4 [StatepointLowering] Schedule gc relocates before uniqueing them
Otherwise we can see an "unexpected" gc.relocate that we uniqued away.

llvm-svn: 264127
2016-03-23 02:24:07 +00:00
George Burgess IV d4febd1612 Keep CodeGenPrepare from preserving the domtree.
CGP modifies the domtree in some cases, so saying that it preserves the
domtree is a lie. We'll be able to selectively preserve it with the new
pass manager.

Differential Revision: http://reviews.llvm.org/D16893

llvm-svn: 264099
2016-03-22 21:25:08 +00:00
Simon Pilgrim c6f5fe3d69 [SelectionDAG] Ensure constant folded legalized vector element types are compatible with the BUILD_VECTOR type
Found during fuzz testing - 32-bit x86 targets were legalizing a <2 x i1> compare result to <2 x i32> when <2 x i64> was expected.

llvm-svn: 264085
2016-03-22 19:59:53 +00:00
Tim Northover b49a8a9dbb CodeGen: check return types match when emitting tail call to builtin.
We were just completely ignoring the types when determining whether we could
safely emit a libcall as a tail call. This is clearly wrong.

Theoretically, we could dig deeper looking for incidental matches (much like
the generic code in Analysis.cpp does), but it's probably not worth it for the
few libcalls that exist.

llvm-svn: 264084
2016-03-22 19:14:38 +00:00
Sanjoy Das eb5037cadc Allow lowering call sites with both funclets and deopt state
Lowering funclets is a no-op, so we can just go ahead and lower the
deopt state.

llvm-svn: 264078
2016-03-22 18:10:39 +00:00
Sanjoy Das 6b535630a1 Add a hasOperandBundlesOtherThan helper, and use it; NFC
llvm-svn: 264072
2016-03-22 17:51:25 +00:00
Simon Pilgrim 25fb4177fb [X86][SSE] Reapplied: Simplify vector LOAD + EXTEND on pre-SSE41 hardware
Improve vector extension of vectors on hardware without dedicated VSEXT/VZEXT instructions.

We already convert these to SIGN_EXTEND_VECTOR_INREG/ZERO_EXTEND_VECTOR_INREG but can further improve this by using the legalizer instead of prematurely splitting into legal vectors in the combine as this only properly helps for lowering to VSEXT/VZEXT.

Removes a lot of unnecessary any_extend + mask pattern - (Fix for PR25718).

Reapplied with a fix for PR26953 (missing vector widening legalization).

Differential Revision: http://reviews.llvm.org/D17932

llvm-svn: 264062
2016-03-22 16:22:08 +00:00
Sanjoy Das 38bfc22161 Add "first class" lowering for deopt operand bundles
Summary:
After this change, deopt operand bundles can be lowered directly by
SelectionDAG into STATEPOINT instructions (which are then lowered to a
call or sequence of nop, with an associated __llvm_stackmaps entry0.
This obviates the need to round-trip deoptimization state through
gc.statepoint via RewriteStatepointsForGC.

Reviewers: reames, atrick, majnemer, JosephTremoulet, pgavlin

Subscribers: sanjoy, mcrosier, majnemer, llvm-commits

Differential Revision: http://reviews.llvm.org/D18257

llvm-svn: 264015
2016-03-22 00:59:13 +00:00
Silviu Baranga 46030585b3 [DAGCombine] Catch the case where extract_vector_elt can cause an any_ext while processing AND SDNodes
Summary:
extract_vector_elt can cause an implicit any_ext if the types don't
match. When processing the following pattern:

  (and (extract_vector_elt (load ([non_ext|any_ext|zero_ext] V))), c)

DAGCombine was ignoring the possible extend, and sometimes removing
the AND even though it was required to maintain some of the bits
in the result to 0, resulting in a miscompile.

This change fixes the issue by limiting the transformation only to
cases where the extract_vector_elt doesn't perform the implicit
extend.

Reviewers: t.p.northover, jmolloy

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18247

llvm-svn: 263935
2016-03-21 11:43:46 +00:00
Craig Topper ea87eae4ca Suppress a -Wunused-variable warning in release builds.
llvm-svn: 263892
2016-03-20 01:17:54 +00:00