Commit Graph

16438 Commits

Author SHA1 Message Date
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
David Blaikie 0a456de5a2 DebugInfo: Introduce DebugLocList to encapsulate a list of DebugLocEntries and an MC Label to refer to them
This removes the magic-number-esque code creating/retrieving the same
label for a debug_loc entry from two places and removes the last small
piece of reusable logic from emitDebugLoc so that there will be less
duplication when refactoring it into two functions (one for debug_loc,
the other for debug_loc.dwo).

llvm-svn: 205382
2014-04-02 01:43:18 +00:00
Adrian Prantl 3c5453cb6e Add a doxygen comment to DebugLocEntry::Merge.
llvm-svn: 205374
2014-04-01 23:34:45 +00:00
David Blaikie 6fa9966ee6 DebugLocEntry: Actually merge the loc entry when returning true.
Seems we didn't have any test coverage for merging... awesome. So I
added some - but hit an llvm-objdump bug while I was there. I'm choosing
not to shave that yak right now.

Code review feedback/bug catch by Adrian Prantl in r205360.

llvm-svn: 205373
2014-04-01 23:19:23 +00:00
David Blaikie 91567b6700 Fix accidental fallthrough in DebugLocEntry::hasSameValueOrLocation
No test case (this would invoke UB by examining uninitialized members,
etc, at best - and this code is apparently untested anyway - I'm about
to fix that)

Code review feedback from Adrian Prantl on r205360.

llvm-svn: 205367
2014-04-01 22:25:09 +00:00
David Blaikie c2af77b027 Remove unused function DebugLocEntry::isEmpty
llvm-svn: 205365
2014-04-01 22:06:18 +00:00
David Blaikie d306baf572 Refactor out the comparison of the location/value in a DebugLocEntry
llvm-svn: 205364
2014-04-01 22:04:07 +00:00
David Blaikie 1275e4f026 DebugInfo: Split DebugLocEntry into its own file.
It seems big enough that it deserves its own file - but it is header
only, so there's no need for another cpp file, etc.

llvm-svn: 205360
2014-04-01 21:49:04 +00:00
Adrian Prantl 75ce62acef DwarfDebug: Prevent DebugLocEntry merging from coalescing two different
constants into only the first one.

rdar://14874886.

llvm-svn: 205357
2014-04-01 21:04:18 +00:00
Matt Arsenault e407ae9846 Make isSetCCEquivalent respect the TargetBooleanContents
llvm-svn: 205336
2014-04-01 18:13:26 +00:00
Matt Arsenault 6310c3f667 Add helpers for checking if a value is a target boolean constant.
llvm-svn: 205335
2014-04-01 18:13:22 +00:00
David Blaikie 0e84adc621 DebugInfo: Factor out common functionality for rendering debug_loc and debug_loc.dwo location list entries
In preparation for refactoring this function into two, one for
debug_loc, one for debug_loc.dwo.

llvm-svn: 205324
2014-04-01 16:17:41 +00:00
David Blaikie 7f1f8742ea Cleanup remaining use of removed variable to fix the build
llvm-svn: 205323
2014-04-01 16:13:29 +00:00
David Blaikie e12ab1276d Simplify debug_loc.dwo handling slightly.
llvm-svn: 205322
2014-04-01 16:09:49 +00:00
David Blaikie 3464161070 DebugInfo: Avoid creating unnecessary/empty line tables and remove the special case of '0' in DwarfCompileUnit::initStmtList by just always using a label difference
This moves one case of raw text checking down into the MCStreamer
interfaces in the form of a virtual function, even if we ultimately end
up consolidating on the one-or-many line tables issue one day, this is
nicer in the interim. This just generally streamlines a bunch of use
cases into a common code path.

llvm-svn: 205287
2014-04-01 08:07:52 +00:00
Adrian Prantl d09ba23faf LTO type uniquing: store the Decl field of a DIImportedEntity as a DIRef.
No other functionality changes, DIBuilder testcase is included in a paired
CFE commit.

This relaxes the assertion in isScopeRef to also accept subclasses of
DIScope.

llvm-svn: 205279
2014-04-01 03:41:04 +00:00
Juergen Ributzka e117992f00 [Stackmaps] Update the stackmap format to use 64-bit relocations for the function address and properly align all entries.
This commit updates the stackmap format to version 1 to indicate the
reorganizaion of several fields. This was done in order to align stackmap
entries to their natural alignment and to minimize padding.

Fixes <rdar://problem/16005902>

llvm-svn: 205254
2014-03-31 22:14:04 +00:00
Matt Arsenault f751d6272d Change shouldSplitVectorElementType to better match the description.
Pass the entire vector type, and not just the element.

llvm-svn: 205247
2014-03-31 20:54:58 +00:00
Hal Finkel b811b6d0d1 Add an optional ability to expand larger BUILD_VECTORs with shuffles
This adds the ability to expand large (meaning with more than two unique
defined values) BUILD_VECTOR nodes in terms of SCALAR_TO_VECTOR and (legal)
vector shuffles. There is now no limit of the size we are capable of expanding
this way, although we don't currently do this for vectors with many unique
values because of the default implementation of TLI's
shouldExpandBuildVectorWithShuffles function.

There is currently no functional change to any existing targets because the new
capabilities are not used unless some target overrides the TLI
shouldExpandBuildVectorWithShuffles function. As a result, I've not included a
test case for the new functionality in this commit, but regression tests will
(at least) be added soon when I commit support for the PPC QPX vector
instruction set.

The benefit of committing this now is that it makes the
shouldExpandBuildVectorWithShuffles callback, which had to be added for other
reasons regardless, fully functional. I suspect that other targets will
also benefit from tuning the heuristic.

llvm-svn: 205243
2014-03-31 19:42:55 +00:00
Hal Finkel 1977514287 Add a TLI hook to control when BUILD_VECTOR might be expanded using shuffles
There are two general methods for expanding a BUILD_VECTOR node:
  1. Use SCALAR_TO_VECTOR on the defined scalar values and then shuffle
     them together.
  2. Build the vector on the stack and then load it.

Currently, we use a fixed heuristic: If there are only one or two unique
defined values, then we attempt an expansion in terms of SCALAR_TO_VECTOR and
vector shuffles (provided that the required shuffle mask is legal). Otherwise,
always expand via the stack. Even when SCALAR_TO_VECTOR is not legal, this
can still be a good idea depending on what tricks the target can play when
lowering the resulting shuffle. If the target can't do anything special,
however, and if SCALAR_TO_VECTOR is expanded via the stack, this heuristic
leads to sub-optimal code (two stack loads instead of one).

Because only the target knows whether the SCALAR_TO_VECTORs and shuffles for a
build vector of a particular type are likely to be optimial, this adds a new
TLI function: shouldExpandBuildVectorWithShuffles which takes the vector type
and the count of unique defined values. If this function returns true, then
method (1) will be used, subject to the constraint that all of the necessary
shuffles are legal (as determined by isShuffleMaskLegal). If this function
returns false, then method (2) is always used.

This commit does not enhance the current code to support expanding a
build_vector with more than two unique values using shuffles, but I'll commit
an implementation of the more-general case shortly.

llvm-svn: 205230
2014-03-31 17:48:10 +00:00
Paul Robinson 7c99ec5b99 Disable each MachineFunctionPass for 'optnone' functions, unless that
pass normally runs at optimization level None, or is part of the
register allocation pipeline.

llvm-svn: 205228
2014-03-31 17:43:35 +00:00
Hal Finkel 02807595fb Look at shuffles of build_vectors in DAGCombiner::visitEXTRACT_VECTOR_ELT
When the loop vectorizer vectorizes code that uses the loop induction variable,
we often end up with IR like this:

  %b1 = insertelement <2 x i32> undef, i32 %v, i32 0
  %b2 = shufflevector <2 x i32> %b1, <2 x i32> undef, <2 x i32> zeroinitializer
  %i = add <2 x i32> %b2, <i32 2, i32 3>

If the add in this example is not legal (as is the case on PPC with VSX), it
will be scalarized, and we'll end up with a number of extract_vector_elt nodes
with the vector shuffle as the input operand, and that vector shuffle is fed by
one or more build_vector nodes. By the time that vector operations are
expanded, visitEXTRACT_VECTOR_ELT will not create new extract_vector_elt by
looking through the vector shuffle (to make sure that no illegal operations are
created), and so the extract_vector_elt -> vector shuffle -> build_vector is
never simplified to an operand of the build vector.

By looking at build_vectors through a shuffle we fix this particular situation,
preventing a vector from being built, only to be deconstructed again (for the
scalarized add) -- an expensive proposition when this all needs to be done via
the stack. We probably want a more comprehensive fix here where we look back
recursively through any shuffles to any build_vectors or scalar_to_vectors,
etc. but that can come later.

llvm-svn: 205179
2014-03-31 11:43:19 +00:00
Hal Finkel 90adf0fe06 Make use of previously generated stores in SelectionDAGLegalize::ExpandExtractFromVectorThroughStack
When expanding EXTRACT_VECTOR_ELT and EXTRACT_SUBVECTOR using
SelectionDAGLegalize::ExpandExtractFromVectorThroughStack, we store the entire
vector and then load the piece we want. This is fine in isolation, but
generating a new store (and corresponding stack slot) for each extraction ends
up producing code of poor quality. When we scalarize a vector operation (using
SelectionDAG::UnrollVectorOp for example) we generate one EXTRACT_VECTOR_ELT
for each element in the vector. This used to generate one stored copy of the
vector for each element in the vector. Now we search the uses of the vector for
a suitable store before generating a new one, which results in much more
efficient scalarization code.

llvm-svn: 205153
2014-03-30 15:10:18 +00:00