Commit Graph

16460 Commits

Author SHA1 Message Date
Adrian Prantl 8714aaf0a5 Re-apply r206096 after investigating the gdb buildbot failure.
Thanks to dblaikie for updating the testcase!

Debug info: (bugfix) C++ C/Dtors can be compiled to multiple functions,
therefore, their declaration cannot have one DW_AT_linkage_name.
The specific instances however can and should have that attribute.

This patch reorders the code in DwarfUnit::getOrCreateSubprogramDIE()
to emit linkage names for C/Dtors.

rdar://problem/16362674.

llvm-svn: 206210
2014-04-14 21:16:04 +00:00
Hal Finkel 56bf297e3a Don't assert in BasicTTI::getMemoryOpCost for non-simple types
BasicTTI::getMemoryOpCost must explicitly check for non-simple types; setting
AllowUnknown=true with TLI->getSimpleValueType is not sufficient because, for
example, non-power-of-two vector types return non-simple EVTs (not MVT::Other).

llvm-svn: 206150
2014-04-14 05:59:09 +00:00
Craig Topper c0196b1b40 [C++11] More 'nullptr' conversion. In some cases just using a boolean check instead of comparing to nullptr.
llvm-svn: 206142
2014-04-14 00:51:57 +00:00
Benjamin Kramer 502b9e1d7f Retire llvm::array_endof in favor of non-member std::end.
While there make array_lengthof constexpr if we have support for it.

llvm-svn: 206112
2014-04-12 16:15:53 +00:00
David Blaikie ee11f22640 PR13337: Omit DW_TAG_restrict_type when compiling for DWARF2
DWARF3 introduced DW_TAG_restrict_type, so avoid using it in prior
versions.

llvm-svn: 206105
2014-04-12 05:35:59 +00:00
Adrian Prantl d3dd11d628 Revert "Debug info: (bugfix) C++ C/Dtors can be compiled to multiple functions,"
This reverts commit 206096 while I investigate why this broke the gdb
buildbot.

llvm-svn: 206103
2014-04-12 04:25:02 +00:00
David Blaikie efc403b91b Use dwarf::Tag rather than unsigned for DIE::Tag to make debugging easier.
Nice to be able to just print out the Tag and have the debugger print
dwarf::DW_TAG_subprogram or whatever, rather than an int.

It's a bit finicky (for example DIDescriptor::getTag still returns
unsigned) because some places still handle real dwarf tags + our fake
tags (one day we'll remove the fake tags, hopefully).

llvm-svn: 206098
2014-04-12 02:24:04 +00:00
Adrian Prantl 1f2f3c3434 Debug info: (bugfix) C++ C/Dtors can be compiled to multiple functions,
therefore, their declaration cannot have one DW_AT_linkage_name.
The specific instances however can and should have that attribute.

This patch reorders the code in DwarfUnit::getOrCreateSubprogramDIE()
to emit linkage names for C/Dtors.

rdar://problem/16362674.

llvm-svn: 206096
2014-04-12 01:44:42 +00:00
Hal Finkel 3b48d08f54 Reenable use of TBAA during CodeGen
We had disabled use of TBAA during CodeGen (even when otherwise using AA)
because the ptrtoint/inttoptr used by CGP for address sinking caused BasicAA to
miss basic type punning that it should catch (and, thus, we'd fail to override
TBAA when we should).

However, when AA is in use during CodeGen, CGP now uses normal GEPs and
bitcasts, instead of ptrtoint/inttoptr, when doing address sinking. As a
result, BasicAA should be able to make us do the right thing in the face of
type-punning, and it seems safe to enable use of TBAA again. self-hosting seems
fine on PPC64/Linux on the P7, with TBAA enabled and -misched=shuffle.

Note: We still don't update TBAA when merging stack slots, although because
BasicAA should now catch all such cases, this is no longer a blocking issue.
Nevertheless, I plan to commit code to deal with this properly in the near
future.

llvm-svn: 206093
2014-04-12 01:26:00 +00:00
Hal Finkel c3998306f4 Add the ability to use GEPs for address sinking in CGP
The current memory-instruction optimization logic in CGP, which sinks parts of
the address computation that can be adsorbed by the addressing mode, does this
by explicitly converting the relevant part of the address computation into
IR-level integer operations (making use of ptrtoint and inttoptr). For most
targets this is currently not a problem, but for targets wishing to make use of
IR-level aliasing analysis during CodeGen, the use of ptrtoint/inttoptr is a
problem for two reasons:
  1. BasicAA becomes less powerful in the face of the ptrtoint/inttoptr
  2. In cases where type-punning was used, and BasicAA was used
     to override TBAA, BasicAA may no longer do so. (this had forced us to disable
     all use of TBAA in CodeGen; something which we can now enable again)

This (use of GEPs instead of ptrtoint/inttoptr) is not currently enabled by
default (except for those targets that use AA during CodeGen), and so aside
from some PowerPC subtargets and SystemZ, there should be no change in
behavior. We may be able to switch completely away from the ptrtoint/inttoptr
sinking on all targets, but further testing is required.

I've doubled-up on a number of existing tests that are sensitive to the
address sinking behavior (including some store-merging tests that are
sensitive to the order of the resulting ADD operations at the SDAG level).

llvm-svn: 206092
2014-04-12 00:59:48 +00:00
Duncan P. N. Exon Smith 689a50736e blockfreq: Rename BlockFrequencyImpl to BlockFrequencyInfoImpl
This is a shared implementation class for BlockFrequencyInfo and
MachineBlockFrequencyInfo, not for BlockFrequency, a related (but
distinct) class.

No functionality change.

<rdar://problem/14292693>

llvm-svn: 206083
2014-04-11 23:20:58 +00:00
Quentin Colombet 4344da1c71 [RegAllocGreedy][Last Chance Recoloring] Change the name of the exhaustive search option.
fexhaustive-register-search => exhaustive-register-search
'f' is a Clang thing!

This is related to PR18747.

llvm-svn: 206075
2014-04-11 21:51:09 +00:00
Quentin Colombet 567e30bc2b [RegAllocGreedy][Last Chance Recoloring] Addition of
-fexhaustive-register-search option to allow an exhaustive search during last
chance recoloring.

This is related to PR18747

Patch by MAYUR PANDEY <mayur.p@samsung.com>. 

llvm-svn: 206072
2014-04-11 21:39:44 +00:00
Quentin Colombet 13c310e3ac [Register Coalescer] Fix wrong live-range information with rematerialization.
When rematerializing an instruction that defines a super register that would be
used by a physical subregisters we use the related physical super register for
the definition.
To keep the live-range information accurate, all the defined subregisters must be
marked as dead def, otherwise the register allocation may miss some
interferences.

Working on a reduced test-case!

<rdar://problem/16582185>

llvm-svn: 206060
2014-04-11 19:45:07 +00:00
Adrian Prantl 3bdcb52dd1 Debug info: Store the DIVariable in DebugLocEntry also for constants,
so DwarfDebug::emitDebugLocEntry can emit them with the correct signedness.

rdar://problem/15928306

llvm-svn: 206042
2014-04-11 17:49:47 +00:00
Matt Arsenault 9ec3cf2c8a Move ExtractVectorElements to SelectionDAG.
This seems generally useful, and makes sense to
go along with SplitVector.

llvm-svn: 206041
2014-04-11 17:47:30 +00:00
Tom Stellard a1a5d9aa2e SelectionDAG: Use helper function to improve legalization of ISD::MUL
The TargetLowering::expandMUL() helper contains lowering code extracted
from the DAGTypeLegalizer and allows the SelectionDAGLegalizer to expand more
ISD::MUL patterns without having to use a library call.

llvm-svn: 206037
2014-04-11 16:12:01 +00:00
Tom Stellard b3a7fa2d17 SelectionDAG: Factor ISD::MUL lowering code out of DAGTypeLegalizer
This code has been moved to a new function in the TargetLowering
class called expandMUL().  The purpose of this is to be able
to share lowering code between the SelectionDAGLegalize and
DAGTypeLegalizer classes.

No functionality changed intended.

llvm-svn: 206036
2014-04-11 16:11:58 +00:00
David Blaikie ceec2bdaa5 Implement depth_first and inverse_depth_first range factory functions.
Also updated as many loops as I could find using df_begin/idf_begin -
strangely I found no uses of idf_begin. Is that just used out of tree?

Also a few places couldn't use df_begin because either they used the
member functions of the depth first iterators or had specific ordering
constraints (I added a comment in the latter case).

Based on a patch by Jim Grosbach. (Jim - you just had iterator_range<T>
where you needed iterator_range<idf_iterator<T>>)

llvm-svn: 206016
2014-04-11 01:50:01 +00:00
Jim Grosbach 5d049b9732 [c++11] Range'ify use list loops in InstrEmitter.
llvm-svn: 206015
2014-04-11 01:13:16 +00:00
Jim Grosbach e816003d3f [c++11] Range'ify use list loops in DAGCombiner.
llvm-svn: 206014
2014-04-11 01:13:13 +00:00
Reid Kleckner 9c6582129a Move the segmented stack switch to a function attribute
This removes the -segmented-stacks command line flag in favor of a
per-function "split-stack" attribute.

Patch by Luqman Aden and Alex Crichton!

llvm-svn: 205997
2014-04-10 22:58:43 +00:00
Adrian Prantl 7f48777609 Debug info: Factor the retrieving of the DIVariable from a MachineInstr
into a function.

llvm-svn: 205973
2014-04-10 17:39:48 +00:00
Jim Grosbach 83b44e1e21 Fix to support properly cleaning up failed address sinking against constants
As it turns out the source of the sunkaddr can be a constant, in which case
there is not an instruction to delete, causing the cleanup code introduced in
r204833 to crash. This patch adds a dynamic check to ensure the deleted value is
in fact an instruction and not a constant.

Patch by Louis Gerbarg <lgg@apple.com>

llvm-svn: 205941
2014-04-10 00:27:45 +00:00
Jim Grosbach cad4cd6c9e SelectionDAG: Don't constant fold target-specific nodes.
FoldConstantArithmetic() only knows how to deal with a few target independent
ISD opcodes. Bail early if it sees a target-specific ISD node. These node do
funny things with operand types which may break the assumptions of the code
that follows, and there's no actual folding that can be done anyway. For example,
non-constant 256 bit vector shifts on X86 have a shift-amount operand that's a
128-bit v4i32 vector regardless of what the first operand type is and that breaks
the assumption that the operand types must match.

rdar://16530923

llvm-svn: 205937
2014-04-09 23:28:11 +00:00
Quentin Colombet 0b1a5584d6 [DAGCombiner] DAG combine does not know how to combine indexed loads with
sign/zero/any extensions. However a few places were not checking properly the
property of the load and were turning an indexed load into a regular extended
load. Therefore the indexed value was lost during the process and this was
triggering an assertion.

<rdar://problem/16389332>

llvm-svn: 205923
2014-04-09 20:03:05 +00:00
David Majnemer a9bdb32f04 WinCOFF: Emit common symbols as specified in the COFF spec
Summary:
Local common symbols were properly inserted into the .bss section.
However, putting external common symbols in the .bss section would give
them a strong definition.

Instead, encode them as undefined, external symbols who's symbol value
is equivalent to their size.

Reviewers: Bigcheese, rafael, rnk

CC: llvm-commits

Differential Revision: http://reviews.llvm.org/D3324

llvm-svn: 205811
2014-04-08 22:33:40 +00:00
Matt Arsenault aaf9623d55 Bug 19348: Check for legal ExtLoad operation before folding
(aext (zextload x)) -> (aext (truncate (*extload x)))

Patch by Stanislav Mekhanoshin!

llvm-svn: 205805
2014-04-08 21:40:37 +00:00
Duncan P. N. Exon Smith a5df813e51 RegAlloc: Account for a variable entry block frequency
Until r197284, the entry frequency was constant -- i.e., set to 2^14.
Although current ToT still has a constant entry frequency, since r197284
that has been an implementation detail (which is soon going to change).

  - r204690 made the wrong assumption for the CSRCost metric.  Adjust
    callee-saved register cost based on entry frequency.

  - r185393 made the wrong assumption (although it was valid at the
    time).  Update SpillPlacement.cpp::Threshold to be relative to the
    entry frequency.

Since ToT still has 2^14 entry frequency, this should have no observable
functionality change.

<rdar://problem/14292693>

llvm-svn: 205789
2014-04-08 19:18:56 +00:00
Andrew Trick 8d007bb5d4 Put a limit on ScheduleDAGSDNodes::ClusterNeighboringLoads to avoid blowing up compile time.
Fixes PR16365 - Extremely slow compilation in -O1 and -O2.

The SD scheduler has a quadratic implementation of load clustering
which absolutely blows up compile time for large blocks with constant
pool loads. The MI scheduler has a better implementation of load
clustering. However, we have not done the work yet to completely
eliminate the SD scheduler. Some benchmarks still seem to benefit from
early load clustering, although maybe by chance.

As an intermediate term fix, I just put a nice limit on the number of
DAG users to search before finding a match. With this limit there are no
binary differences in the LLVM test suite, and the PR16365 test case
does not suffer any compile time impact from this routine.

llvm-svn: 205738
2014-04-07 21:29:22 +00:00
Andrew Trick 326c1f6804 Minor change to StackMapLiveness DEBUG output.
llvm-svn: 205656
2014-04-04 23:49:35 +00:00
Matt Arsenault cf6f688a40 Add DAG parameter to ComputeNumSignBitsForTargetNode
This way, you can check the number of sign bits in the
operands. The depth parameter it already has is pretty useless
without this.

llvm-svn: 205649
2014-04-04 20:13:13 +00:00
Tim Northover 0e5eaae1cb DAGLegalize: add last-ditch type-legalization for VSELECT.
When LLVM sees something like (v1iN (vselect v1i1, v1iN, v1iN)) it can
decide that the result is OK (v1i64 is legal on AArch64, for example)
but it still need scalarising because of that v1i1. There was no code
to do this though.

AArch64 and ARM64 have DAG combines to produce efficient code and
prevent that occuring in *most* such situations, but there are edge
cases that they miss. This adds a legalization to cope with that.

llvm-svn: 205626
2014-04-04 14:49:30 +00:00
Tim Northover 07a8ff4892 ARM64: handle v1i1 types arising from setcc properly.
There were several overlapping problems here, and this solution is
closely inspired by the one adopted in AArch64 in r201381.

Firstly, scalarisation of v1i1 setcc operations simply fails if the
input types are legal. This is fixed in LegalizeVectorTypes.cpp this
time, and allows AArch64 code to be simplified slightly.

Second, vselect with such a setcc feeding into it ends up in
ScalarizeVectorOperand, where it's not handled. I experimented with an
implementation, but found that whatever DAG came out was rather
horrific. I think Hao's DAG combine approach is a good one for
quality, though there are edge cases it won't catch (to be fixed
separately).

Should fix PR19335.

llvm-svn: 205625
2014-04-04 14:49:21 +00:00
Craig Topper 840beec2d0 Make consistent use of MCPhysReg instead of uint16_t throughout the tree.
llvm-svn: 205610
2014-04-04 05:16:06 +00:00
Quentin Colombet 96bd2a1490 [RegAllocGreedy][Last Chance Recoloring] Emit diagnostics when last chance
recoloring cut-offs are encountered and register allocation failed.

This is related to PR18747

Patch by MAYUR PANDEY <mayur.p@samsung.com>.

llvm-svn: 205601
2014-04-04 02:05:21 +00:00
Quentin Colombet 9c816f39ad Revert r205599, the commit was not intended to have so many changes
llvm-svn: 205600
2014-04-04 02:02:49 +00:00
Quentin Colombet 7ee4e79dec [RegAllocGreedy][Last Chance Recoloring] Emit diagnostics when last chance
recoloring cut-offs are hit.

This is related to PR18747.

Patch by MAYUR PANDEY <mayur.p@samsung.com>

llvm-svn: 205599
2014-04-04 01:58:57 +00:00
Eric Christopher bfb38badc1 Fix for PR 19261:
llc doesn't generate nodes for unconditional fall-through branches for targets
without FastISel implementation (X86 has it, but can be disabled by
"-fast-isel=false") in SelectionDAGBuilder::visitBr().

So for line 4 in the following testcase

1: void foo(int i){
2:   switch(i){
3:   default:
4:     break;
5:   }
6:   return;
7: }

there is no corresponding line in .debug_line section, and a debugger
cannot set a breakpoint at line 4.

Fix this by always emitting a branch when we're not optimizing and add a
testcase to ensure that there's code on every line we'd want to break.

Patch by Daniil Fukalov.

llvm-svn: 205529
2014-04-03 12:11:51 +00:00
David Blaikie 12e00fc649 DebugInfo: Use a 64 bit type for the subrange
While we were encoding 64 bit values (data8) in the subrange itself,
using a 32 bit type for the subrange was still confusing the gdb. Oh,
and make it unsigned too.

As the comment points out, this could be pushed into the frontend so
that it would be 32 or 64 bit as appropriate, etc.

llvm-svn: 205512
2014-04-03 06:28:20 +00:00
Lang Hames 3c0dc2a99d [CodeGen] Fix peephole optimizer bug introduced in r205481. Fixes PR19318.
I should have read that comment a little more carefully. ;)

Regression test in the works, committing in the mean time to un-break people.

llvm-svn: 205511
2014-04-03 05:03:20 +00:00
Hal Finkel 6fd19ab35e Account for scalarization costs in BasicTTI::getMemoryOpCost for extending vector loads
When a vector type legalizes to a larger vector type, and the target does not
support the associated extending load (or truncating store), then legalization
will scalarize the load (or store) resulting in an associated scalarization
cost.  BasicTTI::getMemoryOpCost needs to account for this.

Between this, and r205487, PowerPC on the P7 with VSX enabled shows:

MultiSource/Benchmarks/PAQ8p/paq8p: 43% speedup
SingleSource/Benchmarks/BenchmarkGame/puzzle: 51% speedup
SingleSource/UnitTests/Vectorizer/gcc-loops 28% speedup

(some of these are new; some of these, such as PAQ8p, just reverse regressions
that VSX support would trigger)

llvm-svn: 205495
2014-04-03 00:53:59 +00:00
Hal Finkel 55312debee Fix multi-register costs in BasicTTI::getCastInstrCost
For an cast (extension, etc.), the currently logic predicts a low cost if the
associated operation (keyed on the destination type) is legal (or promoted).
This is not true when the number of values required to legalize the type is
changing. For example, <8 x i16> being sign extended by <8 x i32> is not
generically cheap on PPC with VSX, even though sign extension to v4i32 is
legal, because two output v4i32 values are required compared to the single
v8i16 input value, and without custom logic in the target, this conversion will
scalarize.

llvm-svn: 205487
2014-04-02 23:18:54 +00:00
Lang Hames 5dc14bd54c [CodeGen] Teach the peephole optimizer to remember (and exploit) all folding
opportunities in the current basic block, rather than just the last one seen.

<rdar://problem/16478629>

llvm-svn: 205481
2014-04-02 22:59:58 +00:00
Juergen Ributzka fcd2e94ecc Add comments and test case for [DAG] Keep the opaque constant flag when performing unary constant folding operations (r204737).
llvm-svn: 205474
2014-04-02 22:21:01 +00:00
Jim Grosbach 36c4953348 Simplify resolveFrameIndex() signature.
Just pass a MachineInstr reference rather than an MBB iterator.
Creating a MachineInstr& is the first thing every implementation did
anyway.

llvm-svn: 205453
2014-04-02 19:28:18 +00:00
Oliver Stannard b14c625111 ARM: Add support for segmented stacks
Patch by Alex Crichton, ILyoan, Luqman Aden and Svetoslav.

llvm-svn: 205430
2014-04-02 16:10:33 +00:00
Adrian Prantl a731cf0018 clarify comment
llvm-svn: 205429
2014-04-02 15:49:45 +00:00
David Blaikie 326e1fa13b Adjust comments regarding non-relocated abbrev offset in debug_info.dwo
I'm not sure the comment in the implementation really adds a lot of
value (it's clear that we emit zero when no symbol is provided, but it
doesn't explain why we would do that). Happy to iterate.

llvm-svn: 205386
2014-04-02 02:04:51 +00:00
David Blaikie 94c1d7f174 Split debug_loc and debug_loc.dwo emission into two separate functions
Based on code review feedback from Eric Christopher on r204697

llvm-svn: 205385
2014-04-02 01:50:20 +00:00