Commit Graph

8887 Commits

Author SHA1 Message Date
Vedant Kumar 494814d52a [SelectionDAG] Consolidate (t|T)ransferDbgValues methods, NFC.
TransferDbgValues (capital 'T') is wired into ReplaceAllUsesWith, and
transferDbgValues (lowercase 't') is used elsewhere (e.g in Legalize).

Both functions should be doing the exact same thing. This patch
consolidates the logic into one place.

Differential Revision: https://reviews.llvm.org/D40104

llvm-svn: 318448
2017-11-16 19:50:24 +00:00
Yaxun Liu 0844ff2aa7 Fix pointer EVT in SelectionDAGBuilder::visitAlloca
SelectionDAGBuilder::visitAlloca assumes alloca address space is 0, which is
incorrect for triple amdgcn---amdgiz and causes isel failure.

This patch fixes that.

Differential Revision: https://reviews.llvm.org/D40095

llvm-svn: 318392
2017-11-16 12:22:19 +00:00
Sam Parker 43fa5911a1 [DAGCombine] Enable more srl -> load combines
Change the calculation for the desired ValueType for non-sign
extending loads, as in those cases we don't care about the
higher bits. This creates a smaller ExtVT and allows for such
combinations as:
(srl (zextload i16, [addr]), 8) -> (zextload i8, [addr + 1])

Differential Revision: https://reviews.llvm.org/D40034

llvm-svn: 318390
2017-11-16 11:28:26 +00:00
Craig Topper 36e8d66e1a [SelectionDAG] Use report_fatal_error instead of llvm_unreachable in some code that can be reached if targets don't configure things correctly.
For example, this is currently reachable by X86 if you use a masked store intrinsic with a v1iX type.

Using a fatal error seems like a better user experience if someone were to encounter this on a release build. There are several other similar places that have been converted from unreachable to fatal error previously.

llvm-svn: 318379
2017-11-16 06:02:03 +00:00
Yaxun Liu 4d9a4d7ac8 Fix APInt bit size in processDbgDeclares
processDbgDeclares assumes pointer size is the same for different addr spaces.
It uses pointer size for addr space 0 for all pointers, which causes assertion
in stripAndAccumulateInBoundsConstantOffsets for amdgcn---amdgiz since
pointer in addr space 5 has different size than in addr space 0.

This patch fixes that.

Differential Revision: https://reviews.llvm.org/D40085

llvm-svn: 318370
2017-11-16 02:54:49 +00:00
Rong Xu e4572c6b73 [CodeGen] Fix the branch probability assertion in r318202
Due to integer precision, we might have numerator greater than denominator in
the branch probability scaling. Add a check to prevent this from happening.

llvm-svn: 318353
2017-11-16 00:14:05 +00:00
Rong Xu 3573d8da36 [CodeGen] Peel off the dominant case in switch statement in lowering
This patch peels off the top case in switch statement into a branch if the
probability exceeds a threshold. This will help the branch prediction and
avoids the extra compares when lowering into chain of branches.

Differential Revision: http://reviews.llvm.org/D39262

llvm-svn: 318202
2017-11-14 21:44:09 +00:00
Yaxun Liu 0b2f73fd84 CodeGen: Fix TargetLowering::LowerCallTo for sret value type
TargetLowering::LowerCallTo assumes that sret value type corresponds to a
pointer in default address space, which is incorrect, since sret value type
should correspond to a pointer in alloca address space, which may not
be the default address space. This causes assertion for amdgcn target
in amdgiz environment.

This patch fixes that.

Differential Revision: https://reviews.llvm.org/D39996

llvm-svn: 318167
2017-11-14 18:46:52 +00:00
Adrian Prantl 73d0e94e82 Fix an assertion in SelectionDAG::transferDbgValues()
when transferring debug info describing the lower bits of an extended SDNode.

rdar://problem/35504722

llvm-svn: 318086
2017-11-13 21:24:54 +00:00
Craig Topper bdb8db4589 [SelectionDAG] Make getUniformBase in SelectionDAGBuilder fail if any of the middle GEP indices are non-constant.
This is a fix for a bug in r317947. We were supposed to check that all the indices are are constant 0, but instead we're only make sure that indices that are constant are 0. Non-constant indices are being ignored.

llvm-svn: 317950
2017-11-10 23:36:56 +00:00
Craig Topper ffd48e3c27 [SelectionDAG] Teach SelectionDAGBuilder's getUniformBase for gather/scatter handling to accept GEPs with more than 2 operands if the middle operands are all 0s
Currently we can only get a uniform base from a simple GEP with 2 operands. This causes us to miss address folding opportunities for simple global array accesses as the test case shows.

This patch adds support for larger GEPs if the other indices are 0 since those don't require any additional computations to be inserted.

We may also want to handle constant splats of zero here, but I'm leaving that for future work when I have a real world example.

Differential Revision: https://reviews.llvm.org/D39911

llvm-svn: 317947
2017-11-10 22:50:50 +00:00
Amaury Sechet 3f0f650f49 [DAGcombine] Do not replace truncate node by itself when doing constant folding, this trigger needless extra rounds of combine for nothing. NFC
llvm-svn: 317926
2017-11-10 20:59:53 +00:00
Jatin Bhateja aaa5944ad4 [WebAssembly] Fix stack offsets of return values from call lowering.
Summary: Fixes PR35220

Reviewers: vadimcn, alexcrichton

Reviewed By: alexcrichton

Subscribers: pepyakin, alexcrichton, jfb, dschuff, sbc100, jgravelle-google, llvm-commits, aheejin

Differential Revision: https://reviews.llvm.org/D39866

llvm-svn: 317895
2017-11-10 16:26:04 +00:00
Adrian Prantl 1c8c544946 Preserve debug info when DAG-combinging (zext (truncate x)) -> (and x, mask).
rdar://problem/27139077

llvm-svn: 317825
2017-11-09 19:50:20 +00:00
Dan Gohman 2c74fe977d Add an @llvm.sideeffect intrinsic
This patch implements Chandler's idea [0] for supporting languages that
require support for infinite loops with side effects, such as Rust, providing
part of a solution to bug 965 [1].

Specifically, it adds an `llvm.sideeffect()` intrinsic, which has no actual
effect, but which appears to optimization passes to have obscure side effects,
such that they don't optimize away loops containing it. It also teaches
several optimization passes to ignore this intrinsic, so that it doesn't
significantly impact optimization in most cases.

As discussed on llvm-dev [2], this patch is the first of two major parts.
The second part, to change LLVM's semantics to have defined behavior
on infinite loops by default, with a function attribute for opting into
potential-undefined-behavior, will be implemented and posted for review in
a separate patch.

[0] http://lists.llvm.org/pipermail/llvm-dev/2015-July/088103.html
[1] https://bugs.llvm.org/show_bug.cgi?id=965
[2] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118632.html

Differential Revision: https://reviews.llvm.org/D38336

llvm-svn: 317729
2017-11-08 21:59:51 +00:00
Adrian Prantl 93faeecd8f Handle inlined variables in SelectionDAGBuilder::EmitFuncArgumentDbgValue().
In 2010 a commit with no testcase and no further explanation
explicitly disabled the handling of inlined variables in
EmitFuncArgumentDbgValue(). I don't think there is a good reason for
this any more and re-enabling this adds debug locations for variables
associated with an LLVM function argument in functions that are
inlined into the first basic block. The only downside of doing this is
that we may insert a DBG_VALUE before the inlined scope, but (1) this
could be filtered out later, and (2) LiveDebugValues will not
propagate it into subsequent basic blocks if they don't dominate the
variable's lexical scope, so this seems like a small price to pay.

rdar://problem/26228128

llvm-svn: 317702
2017-11-08 18:27:13 +00:00
Matt Arsenault f6ee94c1c6 DAG: Add computeKnownBitsForFrameIndex
Some of the AMDGPU stack addressing modes require knowing the sign
bit is zero. We used to accomplish this by custom lowering
frame indexes, and then putting an AssertZext around a
TargetFrameIndex. This required specifically looking for
the AssextZext + frame index pattern which was moderately
disgusting. The same could probably be accomplished
with a target specific node, but would still
require special handling of frame indexes.

llvm-svn: 317671
2017-11-08 08:52:31 +00:00
David Blaikie 3f833edc7c Target/TargetInstrInfo.h -> CodeGen/TargetInstrInfo.h to match layering
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.

llvm-svn: 317647
2017-11-08 01:01:31 +00:00
Craig Topper 41bf240726 [SelectionDAG] Fix typo in comment. NFC
llvm-svn: 317588
2017-11-07 16:32:31 +00:00
Adrian Prantl 25a09dd408 Make DIExpression::createFragmentExpression() return an Optional.
We can't safely split arithmetic into multiple fragments because we
can't express carry-over between fragments.

llvm-svn: 317534
2017-11-07 00:45:34 +00:00
Sanjay Patel 629c411538 [IR] redefine 'UnsafeAlgebra' / 'reassoc' fast-math-flags and add 'trans' fast-math-flag
As discussed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-November/107104.html
and again more recently:
http://lists.llvm.org/pipermail/llvm-dev/2017-October/118118.html

...this is a step in cleaning up our fast-math-flags implementation in IR to better match
the capabilities of both clang's user-visible flags and the backend's flags for SDNode.

As proposed in the above threads, we're replacing the 'UnsafeAlgebra' bit (which had the 
'umbrella' meaning that all flags are set) with a new bit that only applies to algebraic 
reassociation - 'AllowReassoc'.

We're also adding a bit to allow approximations for library functions called 'ApproxFunc' 
(this was initially proposed as 'libm' or similar).

...and we're out of bits. 7 bits ought to be enough for anyone, right? :) FWIW, I did 
look at getting this out of SubclassOptionalData via SubclassData (spacious 16-bits), 
but that's apparently already used for other purposes. Also, I don't think we can just 
add a field to FPMathOperator because Operator is not intended to be instantiated. 
We'll defer movement of FMF to another day.

We keep the 'fast' keyword. I thought about removing that, but seeing IR like this:
%f.fast = fadd reassoc nnan ninf nsz arcp contract afn float %op1, %op2
...made me think we want to keep the shortcut synonym.

Finally, this change is binary incompatible with existing IR as seen in the 
compatibility tests. This statement:
"Newer releases can ignore features from older releases, but they cannot miscompile 
them. For example, if nsw is ever replaced with something else, dropping it would be 
a valid way to upgrade the IR." 
( http://llvm.org/docs/DeveloperPolicy.html#ir-backwards-compatibility )
...provides the flexibility we want to make this change without requiring a new IR 
version. Ie, we're not loosening the FP strictness of existing IR. At worst, we will 
fail to optimize some previously 'fast' code because it's no longer recognized as 
'fast'. This should get fixed as we audit/squash all of the uses of 'isFast()'.

Note: an inter-dependent clang commit to use the new API name should closely follow 
commit.

Differential Revision: https://reviews.llvm.org/D39304

llvm-svn: 317488
2017-11-06 16:27:15 +00:00
David Blaikie 1be62f0327 Move TargetFrameLowering.h to CodeGen where it's implemented
This header already includes a CodeGen header and is implemented in
lib/CodeGen, so move the header there to match.

This fixes a link error with modular codegeneration builds - where a
header and its implementation are circularly dependent and so need to be
in the same library, not split between two like this.

llvm-svn: 317379
2017-11-03 22:32:11 +00:00
Ayman Musa a37d1130d7 [X86] Fix bug in legalize vector types - Split large loads
When splitting a large load to smaller legally-typed loads, the last load should be padded to reach the size of the previous one so a CONCAT_VECTORS node could reunite them again.
The code currently pads the last load to reach the size of the first load (instead of the previous).

Differential Revision: https://reviews.llvm.org/D38495

Change-Id: Ib60b55ed26ce901fabf68108daf52683fbd5013f
llvm-svn: 317206
2017-11-02 13:07:06 +00:00
Simon Pilgrim 687982c181 [SelectionDAG] computeKnownBits - use ashrInPlace on known bits of ISD::SRA input. NFCI.
llvm-svn: 317087
2017-11-01 13:16:48 +00:00
Craig Topper c51aac675d [DAGCombiner] Fix typos in comments. NFC
llvm-svn: 317072
2017-11-01 03:30:52 +00:00
Simon Pilgrim 9cd7abbcff Fix unused variable warnings. NFCI.
llvm-svn: 316964
2017-10-30 22:38:07 +00:00
Simon Pilgrim 80b371361c [SelectionDAG] Tidyup computeKnownBits extension/truncation cases. NFCI.
We don't need to extend/truncate the Known structure before calling computeKnownBits - it will reset at the start of the function.

llvm-svn: 316962
2017-10-30 22:23:57 +00:00
Daniel Neilson f9c7d29c77 Create instruction classes for identifying any atomicity of memory intrinsic. (NFC)
Summary:
For reference, see: http://lists.llvm.org/pipermail/llvm-dev/2017-August/116589.html

This patch fleshes out the instruction class hierarchy with respect to atomic and
non-atomic memory intrinsics. With this change, the relevant part of the class
hierarchy becomes:

IntrinsicInst
  -> MemIntrinsicBase (methods-only class)
    -> MemIntrinsic (non-atomic intrinsics)
      -> MemSetInst
      -> MemTransferInst
        -> MemCpyInst
        -> MemMoveInst
    -> AtomicMemIntrinsic (atomic intrinsics)
      -> AtomicMemSetInst
      -> AtomicMemTransferInst
        -> AtomicMemCpyInst
        -> AtomicMemMoveInst
    -> AnyMemIntrinsic (both atomicities)
      -> AnyMemSetInst
      -> AnyMemTransferInst
        -> AnyMemCpyInst
        -> AnyMemMoveInst

This involves some class renaming:
    ElementUnorderedAtomicMemCpyInst -> AtomicMemCpyInst
    ElementUnorderedAtomicMemMoveInst -> AtomicMemMoveInst
    ElementUnorderedAtomicMemSetInst -> AtomicMemSetInst
A script for doing this renaming in downstream trees is included below.

An example of where the Any* classes should be used in LLVM is when reasoning
about the effects of an instruction (ex: aliasing).

---
Script for renaming AtomicMem* classes:
PREFIXES="[<,([:space:]]"
CLASSES="MemIntrinsic|MemTransferInst|MemSetInst|MemMoveInst|MemCpyInst"
SUFFIXES="[;)>,[:space:]]"

REGEX="(${PREFIXES})ElementUnorderedAtomic(${CLASSES})(${SUFFIXES})"
REGEX2="visitElementUnorderedAtomic(${CLASSES})"

FILES=$( grep -E "(${REGEX}|${REGEX2})" -r . | tr ':' ' ' | awk '{print $1}' | sort | uniq )

SED_SCRIPT="s~${REGEX}~\1Atomic\2\3~g"
SED_SCRIPT2="s~${REGEX2}~visitAtomic\1~g"

for f in $FILES; do
    echo "Processing: $f"
    sed  -i ".bak" -E "${SED_SCRIPT};${SED_SCRIPT2};${EA_SED_SCRIPT};${EA_SED_SCRIPT2}" $f
done

Reviewers: sanjoy, deadalnix, apilipenko, anna, skatkov, mkazantsev

Reviewed By: sanjoy

Subscribers: hfinkel, jholewinski, arsenm, sdardis, nhaehnle, JDevlieghere, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D38419

llvm-svn: 316950
2017-10-30 19:51:48 +00:00
Simon Pilgrim 017f896adb [SelectionDAG] Add VSELECT demanded elts support to computeKnownBits
llvm-svn: 316947
2017-10-30 19:31:08 +00:00
Simon Pilgrim 96a0b9ef54 [SelectionDAG] Add VSELECT support to computeKnownBits
llvm-svn: 316944
2017-10-30 19:08:21 +00:00
Simon Pilgrim 5da11dfd24 [SelectionDAG] Add SELECT demanded elts support to ComputeNumSignBits
llvm-svn: 316933
2017-10-30 17:53:51 +00:00
Simon Pilgrim 601ae238b7 [SelectionDAG] Add SEXT/AND/XOR/Or demanded elts support to ComputeNumSignBits
llvm-svn: 316875
2017-10-29 22:03:37 +00:00
Simon Pilgrim 7613a7b564 [SelectionDAG] Add SRA/SHL demanded elts support to ComputeNumSignBits
Introduce a isConstOrDemandedConstSplat helper function that can recognise a constant splat build vector for at least the demanded elts we care about.

llvm-svn: 316866
2017-10-29 18:19:37 +00:00
Simon Pilgrim b37a24e82f [SelectionDAG] Add support for INSERT_SUBVECTOR to computeKnownBits
llvm-svn: 316847
2017-10-28 22:10:40 +00:00
Simon Pilgrim d09c1ac20f [SelectionDAG] Support 'bit preserving' floating points bitcasts on computeKnownBits/ComputeNumSignBits
For cases where we know the floating point representations match the bitcasted integer equivalent, allow bitcasting to these types.

This is especially useful for the X86 floating point compare results which return all/zero bits but as a floating point type.

Differential Revision: https://reviews.llvm.org/D39289

llvm-svn: 316831
2017-10-28 14:27:53 +00:00
Guozhi Wei 7c67009fe5 [DAGCombine] Don't combine sext with extload if sextload is not supported and extload has multi users
In function DAGCombiner::visitSIGN_EXTEND_INREG, sext can be combined with extload even if sextload is not supported by target, then

  if sext is the only user of extload, there is no big difference, no harm no benefit.
  if extload has more than one user, the combined sextload may block extload from combining with other zext, causes extra zext instructions generated. As demonstrated by the attached test case.

This patch add the constraint that when sextload is not supported by target, sext can only be combined with extload if it is the only user of extload.

Differential Revision: https://reviews.llvm.org/D39108

llvm-svn: 316802
2017-10-27 21:54:24 +00:00
Matt Arsenault 878827d93a DAG: Fold fma (fneg x), K, y -> fma x, -K, y
llvm-svn: 316753
2017-10-27 09:06:07 +00:00
Sean Fertile 57d46b8436 Add subclass data to the FoldingSetNode for MemIntrinsicSDNodes.
Not having the subclass data on an MemIntrinsicSDNodes means it was possible
to try to fold 2 nodes with the same operands but differing MMO flags. This
would trip an assertion when trying to refine the alignment between the 2
MachineMemOperands.

Differential Revision: https://reviews.llvm.org/D38898

llvm-svn: 316737
2017-10-27 04:02:51 +00:00
Matt Arsenault 8a752b77a2 DAG: Fix creating select with wrong condition type
This code added in r297930 assumed that it could create
a select with a condition type that is just an integer
bitcast of the selected type. For AMDGPU any vselect is
going to be scalarized (although the vector types are legal),
and all select conditions must be i1 (the same as getSetCCResultType).

This logic doesn't really make sense to me, but there's
never really been a consistent policy in what the select
condition mask type is supposed to be. Try to extend
the logic for skipping the transform for condition types
that aren't setccs. It doesn't seem quite right to me though,
but checking conditions that seem more sensible (like whether the
vselect is going to be expanded) doesn't work since this
seems to depend on that also.

llvm-svn: 316554
2017-10-25 07:14:07 +00:00
Adrian Prantl 2eb7cbf987 Implement salavageDebugInfo functionality for SelectionDAG.
Similar to how llvm::salvagDebugInfo hooks into InstCombine, this adds
a hook that can be invoked before an SDNode that is associated with an
SDDbgValue is erased to capture the effect of the deleted node in a
DIExpression.

The motivating example is an SDDebugValue attached to an ADD operation
that gets folded into a LOAD+OFFSET operation.

rdar://problem/32121503

llvm-svn: 316525
2017-10-24 22:55:12 +00:00
Adrian Prantl 4569cedf16 Use range-based for loop. NFC
llvm-svn: 316496
2017-10-24 20:38:00 +00:00
Adrian Prantl 1a043aefc4 Use range-based-for. NFC
llvm-svn: 316485
2017-10-24 19:32:59 +00:00
Adrian Prantl 93a3777b7d Doxygenify comments.
llvm-svn: 316466
2017-10-24 17:23:40 +00:00
Simon Pilgrim 1bc62f03a5 [SelectionDAG] Add VSELECT support to ComputeNumSignBits
llvm-svn: 316457
2017-10-24 16:38:38 +00:00
George Burgess IV 7887238c7c Fix buildbot breakage
SP is only used in an assert. Caused by r316374.

llvm-svn: 316377
2017-10-23 21:08:02 +00:00
George Burgess IV 8a0e4bc972 Don't crash when we see unallocatable registers in clobbers
This fixes a bug where we'd crash given code like the test-case from
https://bugs.llvm.org/show_bug.cgi?id=30792 . Instead, we let the
offending clobber silently slide through.

This doesn't fully fix said bug, since the assembler will still complain
the moment it sees a crypto/fp/vector op, and we still don't diagnose
calls that require vector regs.

Differential Revision: https://reviews.llvm.org/D39030

llvm-svn: 316374
2017-10-23 20:46:36 +00:00
Simon Pilgrim 32da2f9245 [DAGCombine] Permit combining of shuffles of equivalent splat BUILD_VECTORs
combineShuffleOfScalars is very conservative about shuffled BUILD_VECTORs that can be combined together.

This patch adds one additional case - if both BUILD_VECTORs represent splats of the same scalar value but with different UNDEF elements, then we should create a single splat BUILD_VECTOR, sharing only the UNDEF elements defined by the shuffle mask.

Differential Revision: https://reviews.llvm.org/D38696

llvm-svn: 316331
2017-10-23 15:48:08 +00:00
Florian Hahn b0a263cf94 [SelectionDAG] Use dyn_cast without cast.
llvm-svn: 316258
2017-10-21 05:37:10 +00:00
Florian Hahn 3d81254b7c [SelectionDAG] Use isa to silence unused variable warning (NFC).
llvm-svn: 316257
2017-10-21 04:57:03 +00:00
Craig Topper 554151160f [SelectionDAG] Don't subject ConstantSDNodes to the depth limit in computeKnownBits and ComputeNumSignBits.
We don't need to do any additional recursion, we just need to analyze the APInt stored in the node. This matches what the ValueTracking versions do for IR.

llvm-svn: 316256
2017-10-21 03:22:13 +00:00
Craig Topper 195dad4264 [SelectionDAG] Don't subject ISD:Constant to the depth limit in TargetLowering::SimplifyDemandedBits.
Summary:
We shouldn't recurse any further but it doesn't mean we shouldn't be able to give the known bits for a constant. The caller would probably like that we always return the right answer for a constant RHS. This matches what InstCombine does in this case.

I don't have a test case because this showed up while trying to revive D31724.

Reviewers: RKSimon, spatel

Reviewed By: RKSimon

Subscribers: arsenm, llvm-commits

Differential Revision: https://reviews.llvm.org/D38967

llvm-svn: 316255
2017-10-21 02:27:19 +00:00
Craig Topper ff69ffbf9a [SelectionDAG] Add a check to getVectorShuffle to ensure that the only negative index we allow is -1.
llvm-svn: 316183
2017-10-19 20:59:41 +00:00
NAKAMURA Takumi 6f43bd4bde Untabify.
llvm-svn: 316079
2017-10-18 13:31:28 +00:00
Simon Pilgrim 654bbb3b05 [DAGCombine] Add SCALAR_TO_VECTOR undef handling to simplifyShuffleMask.
This allows us to simplify later visitVECTOR_SHUFFLE optimizations such as combineShuffleOfScalars.

Noticed whilst working on D38696

llvm-svn: 316017
2017-10-17 18:14:48 +00:00
Mark Searles 4e3d6160db Use the return value of UpdateNodeOperands(); in some cases, UpdateNodeOperands() modifies the node in-place and using the return value isn’t strictly necessary. However, it does not necessarily modify the node, but may return a resultant node if it already exists in the DAG. See comments in UpdateNodeOperands(). In that case, the return value must be used to avoid such scenarios as an infinite loop (node is assumed to have been updated, so added back to the worklist, and re-processed; however, node hasn’t changed so it is once again passed to UpdateNodeOperands(), assumed modified, added back to worklist; cycle infinitely repeats).
Differential Revision: https://reviews.llvm.org/D38466

llvm-svn: 315957
2017-10-16 23:38:53 +00:00
Krzysztof Parzyszek 72518eaa6f Add iterator range MachineRegisterInfo::liveins(), adopt users, NFC
llvm-svn: 315927
2017-10-16 19:08:41 +00:00
Sjoerd Meijer 7508fbd581 ISel type legalizer: debug messages. NFC.
Minor addition and follow up of r314773 and r311533: this adds more
debug messages to the type legalizer. For each node, it dumps
legalization info for results and operands nodes, rather than just the
final legalized node.

Differential Revision: https://reviews.llvm.org/D38726

llvm-svn: 315904
2017-10-16 14:07:30 +00:00
Aaron Ballman 615eb47035 Reverting r315590; it did not include changes for llvm-tblgen, which is causing link errors for several people.
Error LNK2019 unresolved external symbol "public: void __cdecl `anonymous namespace'::MatchableInfo::dump(void)const " (?dump@MatchableInfo@?A0xf4f1c304@@QEBAXXZ) referenced in function "public: void __cdecl `anonymous namespace'::AsmMatcherEmitter::run(class llvm::raw_ostream &)" (?run@AsmMatcherEmitter@?A0xf4f1c304@@QEAAXAEAVraw_ostream@llvm@@@Z) llvm-tblgen D:\llvm\2017\utils\TableGen\AsmMatcherEmitter.obj 1

llvm-svn: 315854
2017-10-15 14:32:27 +00:00
Matt Arsenault f2db97d8fa DAG: Add opcode and source type to isFPExtFree
This is only currently used for mad/fma transforms.
This is the only case where it should be used for AMDGPU,
so add an opcode to be sure.

llvm-svn: 315740
2017-10-13 19:55:45 +00:00
Matt Arsenault 846dd6b2fa DAG: Add flags to dumps
llvm-svn: 315690
2017-10-13 15:41:40 +00:00
Craig Topper 6794eb8ba1 [SelectionDAG] Cleanup the SIGN_EXTEND_INREG handling in computeKnownBits. NFCI
Use less temporary APInts. Use bit counting more. Don't call getScalarSizeInBits so many places, just capture it once.

llvm-svn: 315671
2017-10-13 05:35:35 +00:00
Craig Topper bde7abe9c9 [SelectionDAG] Fix typo in comment. NFC
llvm-svn: 315670
2017-10-13 05:35:34 +00:00
Craig Topper d6630b9889 [SelectionDAG] Correct the early out in SelectionDAG::getZeroExtendInReg to work properly for vector types.
I don't know if we ever hit this case or not. Turning it into an assert only fired on expanding some atomic operation in a SystemZ lit test.

llvm-svn: 315648
2017-10-13 00:18:58 +00:00
Craig Topper 0e8211ea57 [SelectionDAG] Const-correct the DemandedMask argument to one of the overloads of SimplifyDemandedBits. NFC
llvm-svn: 315641
2017-10-12 23:46:05 +00:00
Craig Topper d52cf99f53 [SelectionDAG] Simplify the ISD::SIGN_EXTEND/ZERO_EXTEND handling to use less temporary APInts by counting bits instead. NFCI
llvm-svn: 315628
2017-10-12 21:58:25 +00:00
Wei Ding 5676acad9e Implement custom lowering for ISD::CTTZ_ZERO_UNDEF and ISD::CTTZ.
Differential Revision: http://reviews.llvm.org/D37348

llvm-svn: 315610
2017-10-12 19:37:14 +00:00
Don Hinton 3e0199f7eb [dump] Remove NDEBUG from test to enable dump methods [NFC]
Summary:
Add LLVM_FORCE_ENABLE_DUMP cmake option, and use it along with
LLVM_ENABLE_ASSERTIONS to set LLVM_ENABLE_DUMP.

Remove NDEBUG and only use LLVM_ENABLE_DUMP to enable dump methods.

Move definition of LLVM_ENABLE_DUMP from config.h to llvm-config.h so
it'll be picked up by public headers.

Differential Revision: https://reviews.llvm.org/D38406

llvm-svn: 315590
2017-10-12 16:16:06 +00:00
Wei Mi 1736efd16a Revert r307036 because of PR34919.
llvm-svn: 315540
2017-10-12 00:24:52 +00:00
Sanjay Patel 34fd5eaaf0 [DAGCombiner] convert insertelement of bitcasted vector into shuffle
Eg:
insert v4i32 V, (v2i16 X), 2 --> shuffle v8i16 V', X', {0,1,2,3,8,9,6,7}

This is a generalization of the IR fold in D38316 to handle insertion into a non-undef vector. 
We may want to abandon that one if we can't find value in squashing the more specific pattern sooner.

We're using the existing legal shuffle target hook to avoid AVX512 horror with vXi1 shuffles.

There may be room for improvement in the shuffle lowering here, but that would be follow-up work.

Differential Revision: https://reviews.llvm.org/D38388

llvm-svn: 315460
2017-10-11 14:12:16 +00:00
Alex Bradbury 4d275f0dfe [TargetLowering] Correctly track NumFixedArgs field of CallLoweringInfo
The NumFixedArgs field of CallLoweringInfo is used by
TargetLowering::LowerCallTo to determine whether a given argument is passed
using the vararg calling convention or not (specifically, to set IsFixed for
each ISD::OutputArg).

Firstly, CallLoweringInfo::setLibCallee and CallLoweringInfo::setCallee both
incorrectly set NumFixedArgs based on the _previous_ args list. Secondly,
TargetLowering::LowerCallTo failed to increment NumFixedArgs when modifying
the argument list so a pointer is passed for the return value.

If your backend uses the IsFixed property or directly accesses NumFixedArgs, 
it is _possible_ this change could result in codegen changes (although the 
previous behaviour would have been incorrect). No such cases have been
identified during code review for any in-tree architecture.

Differential Revision: https://reviews.llvm.org/D37898

llvm-svn: 315457
2017-10-11 13:48:45 +00:00
Eugene Zelenko 149178d92b [CodeGen] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 315380
2017-10-10 22:33:29 +00:00
David Stuttard 51c1b22806 [DAGCombine] Fix for shuffle to vector extend for non power 2 vectors
Summary:
See https://llvm.org/PR33743 for more details

It seems that for non-power of 2 vector sizes, the algorithm can produce
non-matching sizes for input and result causing an assert.

This usually isn't a problem as the isAnyExtend check will weed these out, but
in some cases (most often with lots of undefined values for the mask indices) it
can pass this check for non power of 2 vectors.

Adding in an extra check that ensures that bit size will match for the result
and input (as required)

Subscribers: nhaehnle

Differential Revision: https://reviews.llvm.org/D35241

llvm-svn: 315307
2017-10-10 12:45:45 +00:00
Adam Nemet 0965da2055 Rename OptimizationDiagnosticInfo.* to OptimizationRemarkEmitter.*
Sync it up with the name of the class actually defined here.  This has been
bothering me for a while...

llvm-svn: 315249
2017-10-09 23:19:02 +00:00
Sanjay Patel 2a61a821a0 [DAG] combine assertsexts around a trunc
This was a suggested follow-up to:
D37017 / https://reviews.llvm.org/rL313577

llvm-svn: 315206
2017-10-09 15:22:20 +00:00
Benjamin Kramer 16610028ea Remove unused variables. No functionality change.
llvm-svn: 315185
2017-10-08 19:11:02 +00:00
Craig Topper 90b76211d3 [SelectionDAG} Use KnownBits::isUnknown and hasConflict. NFC
llvm-svn: 315154
2017-10-07 17:07:48 +00:00
Mikael Holmen 0ec1d25d33 Minor refactoring regarding Cast::isNoopCast(), NFC
Summary:
FastISel::hasTrivialKill() was the only user of the "IntPtrTy" version of
Cast::isNoopCast(). According to review comments in D37894 we could instead
use the "DataLayout" version of the method, and thus get rid of the
"IntPtrTy" versions of isNoopCast() completely.

With the above done, the remaining isNoopCast() could then be simplified
a bit more.

Reviewers: arsenm

Reviewed By: arsenm

Subscribers: wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D38497

llvm-svn: 314969
2017-10-05 07:07:09 +00:00
Hans Wennborg 2a6c9adb2f Revert r314886 "[X86] Improvement in CodeGen instruction selection for LEAs (re-applying post required revision changes.)"
It broke the Chromium / SQLite build; see PR34830.

> Summary:
>    1/  Operand folding during complex pattern matching for LEAs has been
>        extended, such that it promotes Scale to accommodate similar operand
>        appearing in the DAG.
>        e.g.
>          T1 = A + B
>          T2 = T1 + 10
>          T3 = T2 + A
>        For above DAG rooted at T3, X86AddressMode will no look like
>          Base = B , Index = A , Scale = 2 , Disp = 10
>
>    2/  During OptimizeLEAPass down the pipeline factorization is now performed over LEAs
>        so that if there is an opportunity then complex LEAs (having 3 operands)
>        could be factored out.
>        e.g.
>          leal 1(%rax,%rcx,1), %rdx
>          leal 1(%rax,%rcx,2), %rcx
>        will be factored as following
>          leal 1(%rax,%rcx,1), %rdx
>          leal (%rdx,%rcx)   , %edx
>
>    3/ Aggressive operand folding for AM based selection for LEAs is sensitive to loops,
>       thus avoiding creation of any complex LEAs within a loop.
>
> Reviewers: lsaba, RKSimon, craig.topper, qcolombet, jmolloy
>
> Reviewed By: lsaba
>
> Subscribers: jmolloy, spatel, igorb, llvm-commits
>
>     Differential Revision: https://reviews.llvm.org/D35014

llvm-svn: 314919
2017-10-04 17:54:06 +00:00
Jatin Bhateja 3c29bacd43 [X86] Improvement in CodeGen instruction selection for LEAs (re-applying post required revision changes.)
Summary:
   1/  Operand folding during complex pattern matching for LEAs has been
       extended, such that it promotes Scale to accommodate similar operand
       appearing in the DAG.
       e.g.
         T1 = A + B
         T2 = T1 + 10
         T3 = T2 + A
       For above DAG rooted at T3, X86AddressMode will no look like
         Base = B , Index = A , Scale = 2 , Disp = 10

   2/  During OptimizeLEAPass down the pipeline factorization is now performed over LEAs
       so that if there is an opportunity then complex LEAs (having 3 operands)
       could be factored out.
       e.g.
         leal 1(%rax,%rcx,1), %rdx
         leal 1(%rax,%rcx,2), %rcx
       will be factored as following
         leal 1(%rax,%rcx,1), %rdx
         leal (%rdx,%rcx)   , %edx

   3/ Aggressive operand folding for AM based selection for LEAs is sensitive to loops,
      thus avoiding creation of any complex LEAs within a loop.

Reviewers: lsaba, RKSimon, craig.topper, qcolombet, jmolloy

Reviewed By: lsaba

Subscribers: jmolloy, spatel, igorb, llvm-commits

    Differential Revision: https://reviews.llvm.org/D35014

llvm-svn: 314886
2017-10-04 09:02:10 +00:00
Bjorn Pettersson 90cc1b53d0 [DebugInfo] Handle endianness when moving debug info for split integer values (reapplied)
Summary:
Take the target's endianness into account when splitting the
debug information in DAGTypeLegalizer::SetExpandedInteger.

This patch fixes so that, for big-endian targets, the fragment
expression corresponding to the high part of a split integer
value is placed at offset 0, in order to correctly represent
the memory address order.

I have attached a PPC32 reproducer where the resulting DWARF
pieces for a 64-bit integer were incorrectly reversed.

Original patch was reverted due to using -stop-after=isel in
the test case (but that is only working when AMDGPU target
is included in the llc build). The test case has now been
updated to use -stop-before=expand-isel-pseudos instead.

Patch by: dstenb

Reviewers: JDevlieghere, aprantl, dblaikie

Reviewed By: JDevlieghere, aprantl, dblaikie

Subscribers: nemanjai

Differential Revision: https://reviews.llvm.org/D38172

llvm-svn: 314781
2017-10-03 11:03:02 +00:00
Sjoerd Meijer 7a22a4948f ISel type legalization: add debug messages. NFCI.
This adds some more debug messages to the type legalizer and functions
like PromoteNode, ExpandNode, ExpandLibCall in an attempt to make
the debug messages a little bit more informative and useful.

Differential Revision: https://reviews.llvm.org/D38450

llvm-svn: 314773
2017-10-03 08:54:15 +00:00
Tim Shen 59465d29f8 [PowerPC] Revert r314666.
See https://reviews.llvm.org/D38172.

I tried to XFAIL it, but sometimes XPASS triggers the bot. Simply
revert it.

llvm-svn: 314739
2017-10-02 23:20:06 +00:00
Michael Liao 70356574bb Remove trailing whitespace to trigger re-cmaking
llvm-svn: 314728
2017-10-02 21:54:38 +00:00
Stanislav Mekhanoshin 6deb212522 Eliminate ftrunc if source is know to be rounded
Differential Revision: https://reviews.llvm.org/D38421

llvm-svn: 314688
2017-10-02 16:57:07 +00:00
Bjorn Pettersson 839775a277 [Debug info] Handle endianness when moving debug info for split integer values
Summary:
Take the target's endianness into account when splitting the
debug information in DAGTypeLegalizer::SetExpandedInteger.

This patch fixes so that, for big-endian targets, the fragment
expression corresponding to the high part of a split integer
value is placed at offset 0, in order to correctly represent
the memory address order.

I have attached a PPC32 reproducer where the resulting DWARF
pieces for a 64-bit integer were incorrectly reversed.

Patch by: dstenb

Reviewers: JDevlieghere, aprantl, dblaikie

Reviewed By: JDevlieghere, aprantl, dblaikie

Subscribers: nemanjai

Differential Revision: https://reviews.llvm.org/D38172

llvm-svn: 314666
2017-10-02 12:46:32 +00:00
Yaxun Liu b33607e5a1 CodeGen: Fix pointer info in expandUnalignedLoad/Store
Currently expandUnalignedLoad/Store uses place holder pointer info for temporary memory operand
in stack, which does not have correct address space. This causes unaligned private double16 load/store to be
lowered to flat_load instead of buffer_load for amdgcn target.

This fixes failures of OpenCL conformance test basic/vload_private/vstore_private on target amdgcn---amdgizcl.

Differential Revision: https://reviews.llvm.org/D35361

llvm-svn: 314566
2017-09-29 23:31:14 +00:00
George Burgess IV f8e11b803d [DAGCombiner] Fix an off-by-one error in vector logic
Without this, we could end up trying to get the Nth (0-indexed) element
from a subvector of size N.

Differential Revision: https://reviews.llvm.org/D37880

llvm-svn: 314380
2017-09-28 06:17:19 +00:00
Eugene Zelenko fa57bd0ced [CodeGen] Fix some Clang-tidy modernize-use-default-member-init and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 314363
2017-09-27 23:26:01 +00:00
Craig Topper 1c781338ee [SelectionDAG] Make NewSDValueDbgMsg print target specific nodes correctly by passing in the SelectionDAG.
llvm-svn: 314271
2017-09-27 05:17:14 +00:00
Craig Topper 5bc10ede53 [SelectionDAG] Teach simplifyDemandedBits to handle shifts by constant splat vectors
This teach simplifyDemandedBits to handle constant splat vector shifts.

This required changing some uses of getZExtValue to getLimitedValue since we can't rely on legalization using getShiftAmountTy for the shift amount.

I believe there may have been a bug in the ((X << C1) >>u ShAmt) handling where we didn't check if the inner shift was too large. I've fixed that here.

I had to add new patterns to ARM because the zext/sext the patterns were trying to look for got turned into an any_extend with this patch. Happy to split that out too, but not sure how to test without this change.

Differential Revision: https://reviews.llvm.org/D37665

llvm-svn: 314139
2017-09-25 19:26:08 +00:00
Reid Kleckner 8898cd8dcf [DebugInfo] Sort the SDDbgValue list before assuming it is in IR order
Summary:
This code iterates the 'Orders' vector in parallel with the DbgValue
list, emitting all DBG_VALUEs that occurred between the last IR order
insertion point and the next insertion point. This assumes the
SDDbgValue list is sorted in IR order, which it usually is. However, it
is not sorted when a node with a debug value is replaced with another
one. When this happens, TransferDbgValues is called, and the new value
is added to the end of the list.

The problem can be solved by stably sorting the list by IR order.

Reviewers: aprantl, Ka-Ka

Reviewed By: aprantl

Subscribers: MatzeB, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D38197

llvm-svn: 314114
2017-09-25 16:14:53 +00:00
Reid Kleckner 09e75c9399 Use {} instead of make_pair and an iterator for the insertion point, NFC
llvm-svn: 314113
2017-09-25 16:14:39 +00:00
Eugene Zelenko fb7f792f55 [CodeGen] Fix some Clang-tidy modernize-use-bool-literals and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 313941
2017-09-21 23:20:16 +00:00
Craig Topper de4379251e [DAGCombiner] Slightly simplify some code by using APInt::isMask() and countTrailingOnes instead of getting active bits and checking if all the bits below that make a mask.
At least for the 64-bit and less case, we should be able to determine if we even have a mask without counting any bits. This also removes the need to explicitly check for 0 active bits, isMask will return false for 0.

llvm-svn: 313908
2017-09-21 20:12:19 +00:00
Reid Kleckner 0fe506bc5e Re-land r313825: "[IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declare"
The fix is to avoid invalidating our insertion point in
replaceDbgDeclare:
     Builder.insertDeclare(NewAddress, DIVar, DIExpr, Loc, InsertBefore);
+    if (DII == InsertBefore)
+      InsertBefore = &*std::next(InsertBefore->getIterator());
     DII->eraseFromParent();

I had to write a unit tests for this instead of a lit test because the
use list order matters in order to trigger the bug.

The reduced C test case for this was:
  void useit(int*);
  static inline void inlineme() {
    int x[2];
    useit(x);
  }
  void f() {
    inlineme();
    inlineme();
  }

llvm-svn: 313905
2017-09-21 19:52:03 +00:00
Bjorn Pettersson 0dde08c3cb [SelectionDAG] Pick correct frame index in LowerArguments
Summary:
SelectionDAGISel::LowerArguments is associating arguments
with frame indices (FuncInfo->setArgumentFrameIndex). That
information is later on used by EmitFuncArgumentDbgValue to
create DBG_VALUE instructions that denotes that a variable
can be found on the stack.

I discovered that for our (big endian) out-of-tree target
the association created by SelectionDAGISel::LowerArguments
sometimes is wrong. I've seen this happen when a 64-bit value
is passed on the stack. The argument will occupy two stack
slots (frame index X, and frame index X+1). The fault is
that a call to setArgumentFrameIndex is associating the
64-bit argument with frame index X+1. The effect is that the
debug information (DBG_VALUE) will point at the least significant
part of the arguement on the stack. When printing the
argument in a debugger I will get the wrong value.

I managed to create a test case for PowerPC that seems to
show the same kind of problem.

The bugfix will look at the datalayout, taking endianness into
account when examining a BUILD_PAIR node, assuming that the
least significant part is in the first operand of the BUILD_PAIR.
For big endian targets we should use the frame index from
the second operand, as the most significant part will be stored
at the lower address (using the highest frame index).

Reviewers: bogner, rnk, hfinkel, sdardis, aprantl

Reviewed By: aprantl

Subscribers: nemanjai, aprantl, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37740

llvm-svn: 313901
2017-09-21 18:52:08 +00:00
Craig Topper 280f133773 [DAGCombiner] Remove duplicate code from visitZERO_EXTEND
This exact block of code exists right below.

Differential Revision: https://reviews.llvm.org/D38122

llvm-svn: 313891
2017-09-21 17:30:02 +00:00
Daniel Jasper 7d2f38d600 Revert r313825: "[IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declare"
.. as well as the two subsequent changes r313826 and r313875.

This leads to segfaults in combination with ASAN. Will forward repro
instructions to the original author (rnk).

llvm-svn: 313876
2017-09-21 12:07:33 +00:00
Craig Topper f0ba300332 [SelectionDAG] Replace a flag that can never be true with an assert.
llvm-svn: 313847
2017-09-21 00:18:46 +00:00
Craig Topper eb0f71f232 [SelectionDAG] Use APInt::getActivebits instead of Bitwidth - leading zeros.
llvm-svn: 313839
2017-09-20 23:48:56 +00:00
Reid Kleckner 3f547e87b2 [IR] Add llvm.dbg.addr, a control-dependent version of llvm.dbg.declare
Summary:
This implements the design discussed on llvm-dev for better tracking of
variables that live in memory through optimizations:
  http://lists.llvm.org/pipermail/llvm-dev/2017-September/117222.html

This is tracked as PR34136

llvm.dbg.addr is intended to be produced and used in almost precisely
the same way as llvm.dbg.declare is today, with the exception that it is
control-dependent. That means that dbg.addr should always have a
position in the instruction stream, and it will allow passes that
optimize memory operations on local variables to insert llvm.dbg.value
calls to reflect deleted stores. See SourceLevelDebugging.rst for more
details.

The main drawback to generating DBG_VALUE machine instrs is that they
usually cause LLVM to emit a location list for DW_AT_location. The next
step will be to teach DwarfDebug.cpp how to recognize more DBG_VALUE
ranges as not needing a location list, and possibly start setting
DW_AT_start_offset for variables whose lifetimes begin mid-scope.

Reviewers: aprantl, dblaikie, probinson

Subscribers: eraman, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D37768

llvm-svn: 313825
2017-09-20 21:52:33 +00:00
Saleem Abdulrasool 432b88e5f4 CodeGen: support SwiftError SwiftCC on Windows x64
Add support for passing SwiftError through a register on the Windows x64
calling convention.  This allows the use of swifterror attributes on
parameters which is used by the swift front end for the `Error`
parameter.  This partially enables building the swift standard library
for Windows x86_64.

llvm-svn: 313791
2017-09-20 18:40:59 +00:00
Saleem Abdulrasool 399a4e9b0b CodeGen: use range based for loops (NFC)
Simplify the RPOT traversal by using a range based for loop for the
iterator dereference.

llvm-svn: 313687
2017-09-19 22:10:20 +00:00
Sanjay Patel f31b1a00ea [DAGCombiner] fold assertzexts separated by trunc
If we have an AssertZext of a truncated value that has already been AssertZext'ed, 
we can assert on the wider source op to improve the zext-y knowledge:
 assert (trunc (assert X, i8) to iN), i1 --> trunc (assert X, i1) to iN

This moves a fold from being Mips-specific to general combining, and x86 shows
improvements.

Differential Revision: https://reviews.llvm.org/D37017

llvm-svn: 313577
2017-09-18 22:05:35 +00:00
Sanjay Patel 7765c93be2 [DAG, x86] allow store merging before and after legalization (PR34217)
rL310710 allowed store merging to occur after legalization to catch stores that are created late,
but this exposes a logic hole seen in PR34217:
https://bugs.llvm.org/show_bug.cgi?id=34217

We will miss merging stores if the target lowers vector extracts into target-specific operations.
This patch allows store merging to occur both before and after legalization if the target chooses
to get maximum merging.

I don't think the potential regressions in the other tests are relevant. The tests are for
correctness of weird IR constructs rather than perf tests, and I think those are still correct.

Differential Revision: https://reviews.llvm.org/D37987

llvm-svn: 313564
2017-09-18 20:54:26 +00:00
Simon Pilgrim 0b21ef1fa3 [SelectionDAG] Add BITCAST handling to ComputeNumSignBits for splatted sign bits.
For cases where we are BITCASTing to vectors of smaller elements, then if the entire source was a splatted sign (src's NumSignBits == SrcBitWidth) we can say that the dst's NumSignBit == DstBitWidth, as we're just splitting those sign bits across multiple elements.

We could generalize this but at the moment the only use case I have is to peek through bitcasts to vector comparison results.

Differential Revision: https://reviews.llvm.org/D37849

llvm-svn: 313543
2017-09-18 16:45:05 +00:00
Hans Wennborg 534bfbd3ba Revert r313343 "[X86] PR32755 : Improvement in CodeGen instruction selection for LEAs."
This caused PR34629: asserts firing when building Chromium. It also broke some
buildbots building test-suite as reported on the commit thread.

> Summary:
>    1/  Operand folding during complex pattern matching for LEAs has been
>        extended, such that it promotes Scale to accommodate similar operand
>        appearing in the DAG.
>        e.g.
>           T1 = A + B
>           T2 = T1 + 10
>           T3 = T2 + A
>        For above DAG rooted at T3, X86AddressMode will no look like
>           Base = B , Index = A , Scale = 2 , Disp = 10
>
>    2/  During OptimizeLEAPass down the pipeline factorization is now performed over LEAs
>        so that if there is an opportunity then complex LEAs (having 3 operands)
>        could be factored out.
>        e.g.
>           leal 1(%rax,%rcx,1), %rdx
>           leal 1(%rax,%rcx,2), %rcx
>        will be factored as following
>           leal 1(%rax,%rcx,1), %rdx
>           leal (%rdx,%rcx)   , %edx
>
>    3/ Aggressive operand folding for AM based selection for LEAs is sensitive to loops,
>       thus avoiding creation of any complex LEAs within a loop.
>
> Reviewers: lsaba, RKSimon, craig.topper, qcolombet
>
> Reviewed By: lsaba
>
> Subscribers: spatel, igorb, llvm-commits
>
> Differential Revision: https://reviews.llvm.org/D35014

llvm-svn: 313376
2017-09-15 18:40:26 +00:00
Jatin Bhateja 908c8b37c2 [X86] PR32755 : Improvement in CodeGen instruction selection for LEAs.
Summary:
   1/  Operand folding during complex pattern matching for LEAs has been
       extended, such that it promotes Scale to accommodate similar operand
       appearing in the DAG.
       e.g.
          T1 = A + B
          T2 = T1 + 10
          T3 = T2 + A
       For above DAG rooted at T3, X86AddressMode will no look like
          Base = B , Index = A , Scale = 2 , Disp = 10

   2/  During OptimizeLEAPass down the pipeline factorization is now performed over LEAs
       so that if there is an opportunity then complex LEAs (having 3 operands)
       could be factored out.
       e.g.
          leal 1(%rax,%rcx,1), %rdx
          leal 1(%rax,%rcx,2), %rcx
       will be factored as following
          leal 1(%rax,%rcx,1), %rdx
          leal (%rdx,%rcx)   , %edx

   3/ Aggressive operand folding for AM based selection for LEAs is sensitive to loops,
      thus avoiding creation of any complex LEAs within a loop.

Reviewers: lsaba, RKSimon, craig.topper, qcolombet

Reviewed By: lsaba

Subscribers: spatel, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D35014

llvm-svn: 313343
2017-09-15 05:29:51 +00:00
Benjamin Kramer 591aac7cdf Remove usages of deprecated std::unary_function and std::binary_function.
These are removed in C++17. We still have some users of
unary_function::argument_type, so just spell that typedef out. No
functionality change intended.

Note that many of the argument types are actually wrong :)

llvm-svn: 313287
2017-09-14 18:33:25 +00:00
Simon Pilgrim 8bd2d8780a [DAGCombine] (shl (or x, c1), c2) -> (or (shl x, c2), c1 << c2)
We already have a combine for this pattern when the input to shl is add, so we just need to enable the transformation when the input is or.

Original patch by @tstellar

Differential Revision: https://reviews.llvm.org/D19325

llvm-svn: 313251
2017-09-14 10:38:30 +00:00
Simon Pilgrim 523483e0bd [SelectionDAG] ComputeNumSignBits - cleanup ROTL/ROTR wrapping to match DAGCombine etc.
Use RotAmt.urem(VTBits) instead of AND(RotAmt, VTBits - 1)

TBH I don't expect non-power-of-2 types to be created, but it makes the logic clearer and matches what we do in other rotation combines.

llvm-svn: 313245
2017-09-14 10:28:01 +00:00
Eugene Zelenko 618c555bbe [CodeGen] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 313194
2017-09-13 21:15:20 +00:00
Craig Topper 8dff57a0ed [SelectionDAG] Remove a check for type being a vector type after calling getShiftAmountTy. NFCI
getShiftAmountTy already returns the vector type when called for vectors.

llvm-svn: 312924
2017-09-11 16:15:39 +00:00
Elena Demikhovsky cc477bbcea Fixed a bug in splitting Scatter operation in the Type Legalizer.
After the split of the Scatter operation, the order of the new instructions is well defined - Lo goes before Hi. Otherwise the semantic of Scatter (from LSB to MSB) is broken.
I'm chaining 2 nodes to prevent reordering.

Differential Revision https://reviews.llvm.org/D37670

llvm-svn: 312894
2017-09-11 06:18:15 +00:00
Adrian Prantl 99ba97726a Fix a crash when emitting debug info for multi-reg function arguments
by reusing more of the existing machinery

This is a follow-up to r312169.
Thanks to Björn Pettersson for the testcase!

llvm-svn: 312773
2017-09-08 02:31:37 +00:00
Matt Arsenault 61ec738b60 DAG: Allow creating extract_vector_elt post-legalize
Fixes some combine issues for AMDGPU where we weren't
getting the many extract_vector_elt combines expected
in a future patch.

This should really be checking isOperationLegalOrCustom on
the extract. That improves a number of x86 lit tests, but
a few get stuck in an infinite loop from one place
where a similar looking extract is created. I have a
different workaround in the backend for that which
keeps many of those improvements, but also adds a few
regressions.

llvm-svn: 312730
2017-09-07 17:24:43 +00:00
Craig Topper 761bb1b53d [DAGCombiner] When combining EXTRACT_SUBVECTOR of a BUILD_VECTOR, make sure we don't create a BUILD_VECTOR with an illegal type after type legalization.
llvm-svn: 312621
2017-09-06 06:50:03 +00:00
Reid Kleckner e33c94f1b0 Add llvm.codeview.annotation to implement MSVC __annotation
Summary:
This intrinsic represents a label with a list of associated metadata
strings. It is modelled as reading and writing inaccessible memory so
that it won't be removed as dead code. I think the intention is that the
annotation strings should appear at most once in the debug info, so I
marked it noduplicate. We are allowed to inline code with annotations as
long as we strip the annotation, but that can be done later.

Reviewers: majnemer

Subscribers: eraman, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D36904

llvm-svn: 312569
2017-09-05 20:14:58 +00:00
Ayman Musa 44cde94935 [X86] Fix crash on assert of non-simple type after type-legalization
The function combineShuffleToVectorExtend in DAGCombine might generate an illegal typed node after "legalize types" phase, causing assertion on non-simple type to fail afterwards.

Adding a type check in case the combine is running after the type legalize pass.

Differential Revision: https://reviews.llvm.org/D37330

llvm-svn: 312438
2017-09-03 09:09:16 +00:00
Craig Topper 7081f029f3 [DAGCombiner] Do a better job of ensuring we don't split elements when combining an extract_subvector of a bitcasted build_vector.
llvm-svn: 312253
2017-08-31 17:02:22 +00:00
Adrian Prantl 608df027fd SelectionDAG: Emit correct debug info for multi-register function arguments.
Previously we would just describe the first register and then call it
quits. This patch emits fragment expressions for each register.

<rdar://problem/34075307>

llvm-svn: 312169
2017-08-30 20:51:20 +00:00
Adrian Prantl b192b545c1 Refactor DIBuilder::createFragmentExpression into a static DIExpression member
NFC

llvm-svn: 312165
2017-08-30 20:04:17 +00:00
Hans Wennborg e7becd7e85 [DAG] Bound loop dependence check in merge optimization.
The loop dependence check looks for dependencies between store merge
candidates not captured by the chain sub-DAG doing a check of
predecessors which may be very large. Conservatively bound number of
nodes checked for compilation time. (Resolves PR34326).

Landing on behalf of Nirav Dave to unblock the 5.0.0 release.

Differential Revision: https://reviews.llvm.org/D37220

llvm-svn: 312022
2017-08-29 18:41:00 +00:00
Craig Topper 029a21dfdc [DAGCombiner] Teach visitEXTRACT_SUBVECTOR to turn extracts of BUILD_VECTOR into smaller BUILD_VECTORs
Only do this before operations are legalized of BUILD_VECTOR is Legal for the target.

Differential Revision: https://reviews.llvm.org/D37186

llvm-svn: 311892
2017-08-28 15:28:33 +00:00
Sanjay Patel a7a61d9768 [DAGCombiner] allow undef shuffle operands when eliminating bitcasts (PR34111)
As noted in the FIXME, this could be improved more, but this is the smallest fix
that helps:
https://bugs.llvm.org/show_bug.cgi?id=34111

llvm-svn: 311853
2017-08-27 17:29:30 +00:00
Jatin Bhateja e4ca95d6aa [DAGCombiner] Extending pattern detection for vector shuffle.
Summary:
If all the operands of a BUILD_VECTOR extract elements from same vector then split the
vector efficiently based on the maximum vector access index.

This will also fix PR 33784

Reviewers: zvi, delena, RKSimon, thakis

Reviewed By: RKSimon

Subscribers: chandlerc, eladcohen, llvm-commits

Differential Revision: https://reviews.llvm.org/D35788

llvm-svn: 311833
2017-08-26 19:02:36 +00:00
Jatin Bhateja b60cfbefac Revert rL311247 : To rectify commit message.
Summary: This reverts commit rL311247.

Differential Revision: https://reviews.llvm.org/D36927

llvm-svn: 311832
2017-08-26 19:02:17 +00:00
Sanjay Patel e404cbff66 [DAG] convert vector select-of-constants to logic/math
This goes back to a discussion about IR canonicalization. We'd like to preserve and convert
more IR to 'select' than we currently do because that's likely the best choice in IR:
http://lists.llvm.org/pipermail/llvm-dev/2016-September/105335.html
...but that's often not true for codegen, so we need to account for this pattern coming in
to the backend and transform it to better DAG ops.

Steps in this patch:

  1. Add an EVT param to the existing convertSelectOfConstantsToMath() TLI hook to more finely
     enable this transform. Other targets will probably want that anyway to distinguish scalars
     from vectors. We're using that here to exclude AVX512 targets, but it may not be necessary.

  2. Convert a vselect to ext+add. This eliminates a constant load/materialization, and the
     vector ext is often free.

Implementing a more general fold using xor+and can be a follow-up for targets that don't have
a legal vselect. It's also possible that we can remove the TLI hook for the special case fold
implemented here because we're eliminating a constant, but it needs to be tested on other
targets.

Differential Revision: https://reviews.llvm.org/D36840

llvm-svn: 311731
2017-08-24 23:24:43 +00:00
Victor Leschuk 6aedf785c5 Remove duplicate code
llvm-svn: 311675
2017-08-24 17:02:38 +00:00
Victor Leschuk 471579b52e Add missing break in switch
llvm-svn: 311673
2017-08-24 16:57:10 +00:00
Wei Ding a131d3fb29 Add ‘llvm.experimental.constrained.fma‘ Intrinsic.
Differential Revision: http://reviews.llvm.org/D36335

llvm-svn: 311629
2017-08-24 04:18:24 +00:00
Hans Wennborg c39ec95d88 [DAG] Fix Node Replacement in PromoteIntBinOp
When one operand is a user of another in a promoted binary operation
we may replace and delete the returned value before returning
triggering an assertion. Reorder node replacements to prevent this.

Fixes PR34137.

Landing on behalf of Nirav.

Differential Revision: https://reviews.llvm.org/D36581

llvm-svn: 311623
2017-08-24 01:08:27 +00:00
Adrian Prantl 7db6b5e2b3 Retire the llvm.dbg.mir hack after r311594.
llvm-svn: 311610
2017-08-23 22:02:36 +00:00
Craig Topper 35189d5221 [SelectionDAG] Make ISD::isConstantSplatVector always return an element sized APInt.
This partially reverts r311429 in favor of making ISD::isConstantSplatVector do something not confusing. Turns out the only other user of it was also having to deal with the weird property of it returning a smaller size.

So rather than continue to deal with this quirk everywhere, just make the interface do something sane.

Differential Revision: https://reviews.llvm.org/D37039

llvm-svn: 311510
2017-08-22 23:54:13 +00:00
Jonas Devlieghere a680a8f5f8 [Debug info] Add new DbgValues after looping over DAG
I was contacted by Jesper Antonsson from Ericsson who ran into problems
with r311181 in their test suites with for an out-of-tree target.
Because of the latter I don't have a reproducer, but we definitely don't
want to modify the data structure on which we are iterating inside the
loop.

llvm-svn: 311466
2017-08-22 16:28:07 +00:00
Renato Golin c070c73d5e [ARM] Avoid creating duplicate ANDs in SelectionDAG
When expanding a BRCOND into a BR_CC, do not create an AND 1
if one already exists.

Review: D36705

Patch by Joel Galenson <jgalenson@google.com>

llvm-svn: 311447
2017-08-22 11:02:45 +00:00
Sjoerd Meijer e0c933f5d6 [SelectionDAG] Add getNode debug messages
This adds debug messages to various functions that create new SDValue nodes.
This is e.g. useful to have during legalization, as otherwise it can prints
legalization info of nodes that did not appear in the dumps before.

Differential Revision: https://reviews.llvm.org/D36984

llvm-svn: 311444
2017-08-22 10:43:51 +00:00
Craig Topper b49f0893b2 [X86] Prevent several calls to ISD::isConstantSplatVector from returning a narrower APInt than the original scalar type
ISD::isConstantSplatVector can shrink to the smallest splat width. But we don't check the size of the resulting APInt at all. This can cause us to misinterpret the results.

This patch just adds a flag to prevent the APInt from changing width.

Fixes PR34271.

Differential Revision: https://reviews.llvm.org/D36996

llvm-svn: 311429
2017-08-22 05:40:17 +00:00
Benjamin Kramer 49a49fe816 Move helper classes into anonymous namespaces.
No functionality change intended.

llvm-svn: 311288
2017-08-20 13:03:48 +00:00
Jatin Bhateja 6b4c205685 [DAGCombiner] Extending pattern detection for vector shuffle.
Summary:
    If all the operands of a BUILD_VECTOR extract elements from same vector then split the
    vector efficiently based on the maximum vector access index.

    Reviewers: zvi, delena, RKSimon, thakis

    Reviewed By: RKSimon

    Subscribers: chandlerc, eladcohen, llvm-commits

    Differential Revision: https://reviews.llvm.org/D35788

llvm-svn: 311255
2017-08-19 18:08:59 +00:00
Jatin Bhateja 66f7958e91 Revert rL311247 : To rectify commit message.
Summary: This reverts commit rL311247.

Differential Revision: https://reviews.llvm.org/D36927

llvm-svn: 311252
2017-08-19 17:59:58 +00:00
Jatin Bhateja 6f0d0d23b0 Merge branch 'arcpatch-D35788'
llvm-svn: 311247
2017-08-19 17:00:04 +00:00
Jatin Bhateja 1c56863739 Revert rL311242 "Extension of shuffle vector pattern detection, updating post rebase."
Summary:

This reverts commit rL311242.

Differential Revision: https://reviews.llvm.org/D36924

llvm-svn: 311246
2017-08-19 16:40:06 +00:00
Jatin Bhateja 313f97dd84 Extension of shuffle vector pattern detection, updating post rebase.
llvm-svn: 311242
2017-08-19 15:58:36 +00:00
Jonas Devlieghere e101b07a1d [Debug info] Transfer DI to fragment expressions for split integer values.
This patch teaches the SDag type legalizer how to split up debug info for
integer values that are split into a hi and lo part.

(re-commit)

Differential Revision: https://reviews.llvm.org/D36805

llvm-svn: 311181
2017-08-18 18:07:00 +00:00
Craig Topper e3edd9c9be [DAGCombiner] Fix bad comment that had immediate values swapped from the code and what they need to be to make sense. NFC
llvm-svn: 311144
2017-08-18 04:52:46 +00:00
Jonas Devlieghere 30756da212 Revert "[Debug info] Transfer DI to fragment expressions for split integer values."
This reverts commit r311102.

llvm-svn: 311111
2017-08-17 17:58:33 +00:00
Jonas Devlieghere 622fedc001 [Debug info] Transfer DI to fragment expressions for split integer values.
This patch teaches the SDag type legalizer how to split up debug info for
integer values that are split into a hi and lo part.

Differential Revision: https://reviews.llvm.org/D36805

llvm-svn: 311102
2017-08-17 17:06:48 +00:00
Adrian Prantl 6a57daad81 Improve line debug info when translating a CaseBlock to SDNodes.
The SelectionDAGBuilder translates various conditional branches into
CaseBlocks which are then translated into SDNodes. If a conditional
branch results in multiple CaseBlocks only the first CaseBlock is
translated into SDNodes immediately, the rest of the CaseBlocks are
put in a queue and processed when all LLVM IR instructions in the
basic block have been processed.

When a CaseBlock is transformed into SDNodes the SelectionDAGBuilder
is queried for the current LLVM IR instruction and the resulting
SDNodes are annotated with the debug info of the current
instruction (if it exists and has debug metadata).

When the deferred CaseBlocks are processed, the SelectionDAGBuilder
does not have a current LLVM IR instruction, and the resulting SDNodes
will not have any debuginfo. As DwarfDebug::beginInstruction() outputs
a .loc directive for the first instruction in a labeled
block (typically the case for something coming from a CaseBlock) this
tends to produce a line-0 directive.

This patch changes the handling of CaseBlocks to store the current
instruction's debug info into the CaseBlock when it is created (and the
SelectionDAGBuilder knows the current instruction) and to always use
the stored debug info when translating a CaseBlock to SDNodes.

Patch by Frej Drejhammar!

Differential Revision: https://reviews.llvm.org/D36671

llvm-svn: 311097
2017-08-17 16:57:13 +00:00
Simon Pilgrim 8be9f4af4f [DAGCombiner] Add support for non-uniform constant vectors to (mul x, (1 << c)) -> x << c
llvm-svn: 311083
2017-08-17 13:03:34 +00:00
Elad Cohen 124d32829c [SelectionDAG] Teach the vector-types operand scalarizer about SETCC
When v1i1 is legal (e.g. AVX512) the legalizer can reach
a case where a v1i1 SETCC with an illgeal vector type operand
wasn't scalarized (since v1i1 is legal) but its operands does
have to be scalarized. This used to assert because SETCC was
missing from the vector operand scalarizer.

This patch attemps to teach the legalizer to handle these cases
by scalazring the operands, converting the node into a scalar
SETCC node.

Differential revision: https://reviews.llvm.org/D36651

llvm-svn: 311071
2017-08-17 08:06:36 +00:00
Andrew Kaylor 53a5fbb45f Add strictfp attribute to prevent unwanted optimizations of libm calls
Differential Revision: https://reviews.llvm.org/D34163

llvm-svn: 310885
2017-08-14 21:15:13 +00:00
Amaury Sechet 9c529b6be3 [DAGCombine] Do not try to deduplicate commutative operations if both operand are the same.
Summary: It is creating useless work as the commuted nodes is the same as the node we are working on in that case.

Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33840

llvm-svn: 310832
2017-08-14 11:44:03 +00:00
Elad Cohen 6a9edda356 [SelectionDAG] combine vextract (v1iX extract_subvector(vNiX, Idx))
into vextract(vNiX,Idx) when creating vextract with getNode().
This case appeared in AVX512 after fixing pr33349 in r310552.

Differential revision: https://reviews.llvm.org/D36571

llvm-svn: 310828
2017-08-14 10:49:45 +00:00
Elad Cohen 3a90a0c10d Revert "[DAGCombiner] Extending pattern detection for vector shuffle (REAPPLIED)"
This reverts commit r310782.

llvm-svn: 310822
2017-08-14 09:06:00 +00:00
Craig Topper 2251ef95a3 [X86][ARM][TargetLowering] Add SrcVT to isExtractSubvectorCheap
Summary:
Without the SrcVT its hard to know what is really being asked for. For example if your target has 128, 256, and 512 bit vectors. Maybe extracting 128 from 256 is cheap, but maybe extracting 128 from 512 is not.

For x86 we do support extracting a quarter of a 512-bit register. But for i1 vectors we don't have isel patterns for extracting arbitrary pieces. So we need this to have a correct implementation of isExtractSubvectorCheap for mask vectors.

Reviewers: RKSimon, zvi, efriedma

Reviewed By: RKSimon

Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D36649

llvm-svn: 310793
2017-08-13 17:29:07 +00:00
Simon Pilgrim 5a86f0e717 [DAGCombiner] Extending pattern detection for vector shuffle (REAPPLIED)
If all the operands of a BUILD_VECTOR extract elements from same vector then split the vector efficiently based on the maximum vector access index.

Reapplied with fix to only work with simple value types.

Committed on behalf of @jbhateja (Jatin Bhateja)

Differential Revision: https://reviews.llvm.org/D35788

llvm-svn: 310782
2017-08-12 17:43:25 +00:00
Sanjay Patel 169dae70a6 [x86] use more shift or LEA for select-of-constants (2nd try)
The previous rev (r310208) failed to account for overflow when subtracting the
constants to see if they're suitable for shift/lea. This version add a check
for that and more test were added in r310490.

We can convert any select-of-constants to math ops:
http://rise4fun.com/Alive/d7d

For this patch, I'm enhancing an existing x86 transform that uses fake multiplies
(they always become shl/lea) to avoid cmov or branching. The current code misses
cases where we have a negative constant and a positive constant, so this is just
trying to plug that hole.

The DAGCombiner diff prevents us from hitting a terrible inefficiency: we can start
with a select in IR, create a select DAG node, convert it into a sext, convert it
back into a select, and then lower it to sext machine code.

Some notes about the test diffs:

1. 2010-08-04-MaskedSignedCompare.ll - We were creating control flow that didn't exist in the IR.
2. memcmp.ll - Choose -1 or 1 is the case that got me looking at this again. We could avoid the 
   push/pop in some cases if we used 'movzbl %al' instead of an xor on a different reg? That's a 
   post-DAG problem though.
3. mul-constant-result.ll - The trade-off between sbb+not vs. setne+neg could be addressed if
   that's a regression, but those would always be nearly equivalent.
4. pr22338.ll and sext-i1.ll - These tests have undef operands, so we don't actually care about these diffs.
5. sbb.ll - This shows a win for what is likely a common case: choose -1 or 0.
6. select.ll - There's another borderline case here: cmp+sbb+or vs. test+set+lea? Also, sbb+not vs. setae+neg shows up again.
7. select_const.ll - These are motivating cases for the enhancement; replace cmov with cheaper ops.

Assembly differences between movzbl and xor to avoid a partial reg stall are caused later by the X86 Fixup SetCC pass.

Differential Revision: https://reviews.llvm.org/D35340

llvm-svn: 310717
2017-08-11 15:44:14 +00:00
Nirav Dave 0a48e5d506 Improve handling of insert_subvector of bitcast values
Fix insert_subvector / extract_subvector merges of bitcast values.

Reviewers: efriedma, craig.topper, RKSimon

Subscribers: RKSimon, llvm-commits

Differential Revision: https://reviews.llvm.org/D34571

llvm-svn: 310711
2017-08-11 13:21:41 +00:00
Nirav Dave d1b3f09faa [X86][DAG] Switch X86 Target to post-legalized store merge
Move store merge to happen after intrinsic lowering to allow lowered
stores to be merged.

Some regressions due in MergeConsecutiveStores to missing
insert_subvector that are addressed in follow up patch.

Reviewers: craig.topper, efriedma, RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34559

llvm-svn: 310710
2017-08-11 13:21:35 +00:00
Simon Pilgrim 83cf3a29b5 [DAGCombiner] Remove shuffle support from simplifyShuffleMask
rL310372 enabled simplifyShuffleMask to support undef shuffle mask inputs, but its causing hangs.

Removing support until I can triage the problem

llvm-svn: 310699
2017-08-11 08:37:00 +00:00
Nirav Dave f8556ad48f Revert "[DAG] Cleanup unused nodes after store merge. NFCI."
This reverts commit r310648 which causes an unexpected assertion failure

llvm-svn: 310659
2017-08-10 21:03:36 +00:00
Nirav Dave 4d28c0ff4f [DAG] Relax type restriction for store merge
Summary: Allow stores of bitcastable types to be merged by peeking through BITCAST nodes and recasting stored values constant and vector extract nodes as necessary.

Reviewers: jyknight, hfinkel, efriedma, RKSimon, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34569

llvm-svn: 310655
2017-08-10 19:52:45 +00:00
Nirav Dave 99d9d24553 [DAG] Cleanup unused nodes after store merge. NFCI.
llvm-svn: 310648
2017-08-10 18:53:14 +00:00
Nirav Dave 06242a99ce [DAG] Rewrite expression. NFC.
llvm-svn: 310608
2017-08-10 15:29:33 +00:00
Nirav Dave 926e2d39bf [X86] Keep dependencies when constructing loads in combineStore
Summary:
Preserve chain dependecies between old and new loads constructed to
prevent loads from reordering below later stores.

Fixes PR34088.

Reviewers: craig.topper, spatel, RKSimon, efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36528

llvm-svn: 310604
2017-08-10 15:12:32 +00:00
Guy Blank 136b543745 [SelectionDAG] Allow constant folding for implicitly truncating BUILD_VECTOR nodes.
In FoldConstantArithmetic, handle BUILD_VECTOR nodes that do implicit truncation on the elements.

This is similar to what is done in FoldConstantVectorArithmetic.

Differential Revision:
https://reviews.llvm.org/D36506

llvm-svn: 310593
2017-08-10 14:09:50 +00:00
Elad Cohen 22ba97a0a6 [SelectionDAG] When scalarizing vselect, don't assert on
a legal cond operand.

When scalarizing the result of a vselect, the legalizer currently expects
to already have scalarized the operands. While this is true for the true/false
operands (which have the same type as the result), it is not case for the
condition operand. On X86 AVX512, v1i1 is legal - this leads to operations such
as '< N x type> vselect < N x i1> < N x type> < N x type>' where < N x type > is
illegal to hit an assertion during the scalarization.

The handling is similar to r205625.
This also exposes the fact that (v1i1 extract_subvector) should be legal
and selectable on AVX512 - We do this by custom lowering to vector_extract_elt.
This still leaves us in some cases with redundant dag nodes which will be
combined in a separate soon to come patch.

This fixes pr33349.

Differential revision: https://reviews.llvm.org/D36511

llvm-svn: 310552
2017-08-10 07:44:23 +00:00
David Blaikie 76fb649b0d Reduce variable scope by moving declaration into if clause
llvm-svn: 310506
2017-08-09 18:34:18 +00:00
Nirav Dave 6110d3ad00 [DAG] Explicitly cleanup merged load values during store merge. NFCI.
llvm-svn: 310474
2017-08-09 13:37:07 +00:00
Nirav Dave 8a813cf646 [DAG] Introduce peekThroughBitcast function. NFCI.
llvm-svn: 310405
2017-08-08 20:01:18 +00:00
Nirav Dave 515116d7c2 [DAG] Update comments. NFC.
llvm-svn: 310404
2017-08-08 19:52:19 +00:00
Simon Pilgrim 91b7b991d4 [DAGCombiner] simplifyShuffleMask - handle UNDEF inputs from shuffles as well as BUILD_VECTOR
Minor extension to D36393

llvm-svn: 310372
2017-08-08 16:10:33 +00:00
Simon Pilgrim ef44228acb [DAGCombiner] Simplify shuffle mask index if the referenced input element is UNDEF
Fixes one of the cases in PR34041.

Differential Revision: https://reviews.llvm.org/D36393

llvm-svn: 310344
2017-08-08 11:03:30 +00:00
Sanjay Patel 807f92b8ff [x86] revert r310208 to investigate test-suite failures (PR34105 / PR34097)
llvm-svn: 310264
2017-08-07 15:47:48 +00:00
Nirav Dave 3d3bde7682 [DAG] Extend visitSCALAR_TO_VECTOR optimization to truncated vector.
Relanding after case to insert explicit truncation as necessary.

Allow SCALAR_TO_VECTOR of EXTRACT_VECTOR_ELT to reduce to
EXTRACT_SUBVECTOR of vector shuffle when output is smaller. Marginally
improves vector shuffle computations.

Reviewers: efriedma, RKSimon, spatel

Subscribers: javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D35566

llvm-svn: 310256
2017-08-07 14:07:49 +00:00
Guy Blank 5ca01695f7 [SelectionDAG] reset NewNodesMustHaveLegalTypes flag between basic blocks
The NewNodesMustHaveLegalTypes flag is set to false at the beginning of CodeGenAndEmitDAG, and set to true after legalizing types.
But before calling CodeGenAndEmitDAG we build the DAG for the basic block.
So for the first basic block NewNodesMustHaveLegalTypes would be 'false' during the SDAG building, and for all other basic blocks it would be 'true'.

This patch sets the flag to false before SDAG building each basic block.

Differential Revision:
https://reviews.llvm.org/D33435

llvm-svn: 310239
2017-08-07 05:51:14 +00:00
Sanjay Patel a923c2ee95 [x86] use more shift or LEA for select-of-constants
We can convert any select-of-constants to math ops:
http://rise4fun.com/Alive/d7d

For this patch, I'm enhancing an existing x86 transform that uses fake multiplies 
(they always become shl/lea) to avoid cmov or branching. The current code misses 
cases where we have a negative constant and a positive constant, so this is just 
trying to plug that hole.

The DAGCombiner diff prevents us from hitting a terrible inefficiency: we can start 
with a select in IR, create a select DAG node, convert it into a sext, convert it 
back into a select, and then lower it to sext machine code.

Some notes about the test diffs:

1. 2010-08-04-MaskedSignedCompare.ll - We were creating control flow that didn't exist in the IR.
2. memcmp.ll - Choose -1 or 1 is the case that got me looking at this again. I 
   think we could avoid the push/pop in some cases if we used 'movzbl %al' instead of an xor on 
   a different reg? That's a post-DAG problem though.
3. mul-constant-result.ll - The trade-off between sbb+not vs. setne+neg could be addressed if 
   that's a regression, but I think those would always be nearly equivalent.
4. pr22338.ll and sext-i1.ll - These tests have undef operands, so I don't think we actually care about these diffs.
5. sbb.ll - This shows a win for what I think is a common case: choose -1 or 0.
6. select.ll - There's another borderline case here: cmp+sbb+or vs. test+set+lea? Also, sbb+not vs. setae+neg shows up again.
7. select_const.ll - These are motivating cases for the enhancement; replace cmov with cheaper ops.

Assembly differences between movzbl and xor to avoid a partial reg stall are caused later by the X86 Fixup SetCC pass.

Differential Revision: https://reviews.llvm.org/D35340

llvm-svn: 310208
2017-08-06 16:27:07 +00:00
Nico Weber b24df62bb6 Revert r310058, it caused PR34073.
llvm-svn: 310118
2017-08-04 20:24:13 +00:00
Simon Pilgrim 5c63586489 [DAGCombiner] Extending pattern detection for vector shuffle.
If all the operands of a BUILD_VECTOR extract elements from same vector then split the vector efficiently based on the maximum vector access index.

Committed on behalf of @jbhateja (Jatin Bhateja)

Differential Revision: https://reviews.llvm.org/D35788

llvm-svn: 310058
2017-08-04 12:46:35 +00:00
Matt Arsenault a52391f2db DAG: Provide access to Pass instance from SelectionDAG
This allows accessing an analysis pass during lowering.

llvm-svn: 309991
2017-08-03 21:54:00 +00:00
Nirav Dave 3fc1c2365c [DAG] Allow merging of stores of vector loads
Remove restriction disallowing merging of stores vector loads into
larger store of larger vector load.

Reviewers: RKSimon, efriedma, spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36158

llvm-svn: 309951
2017-08-03 15:51:20 +00:00
Nirav Dave e44032f7e7 [DAG] Improve candidate pruning in store merge failure case. NFCI
During store merge we construct a sorted list of consecutive store
candidates and consider subsequences for merging into a single
store. For each subsequence we check if the stored value type is legal
the merged store would have valid and fast and if the constructed
value to be stored is valid. The only properties that affect this
check between subsequences is the size of the subsequence, the
alignment of the first store, the alignment of the stored load value
(when merging stores-of-loads), and whether the merged value is a
constant zero.

If we do not find a viable mergeable subsequence starting from the
first store of length N, we know that a subsequence starting at a
later store of length N will also fail unless the new store's
alignment, the new load's alignment (if we're merging store-of-loads),
or we've dropped stores of nonzero value and could construct a merged
stores of zero (for merging constants).

As a result if we fail to find a valid subsequence starting from the
first store we can safely skip considering subsequences that start
with subsequent stores unless one of the above properties is
true. This significantly (2x) improves compile time in some
pathological cases.

Reviewers: RKSimon, efriedma, zvi, spatel, waltl

Subscribers: grandinj, llvm-commits

Differential Revision: https://reviews.llvm.org/D35901

llvm-svn: 309830
2017-08-02 16:35:58 +00:00
Nirav Dave 15894f8dec [DAG] Refactor store merge subexpressions. NFC.
Distribute various expressions across ifs.

llvm-svn: 309777
2017-08-02 01:08:38 +00:00
Matt Arsenault acc5e82b0e DAG: Undo and->or combine with FrameIndexes
This pattern shows up when lowering byval copies on AMDGPU.

The byval object access is split into 4-byte chunks, adding a
constant offset to the FixedStack base. When some of the offsets
turn into ors, this prevents combining the constant offsets.

This makes it not apparent that the object is there when matching
addressing modes, so it ends up using a scratch wave offset
relative access and the lengthy frame index expansion for that.

llvm-svn: 309775
2017-08-02 00:43:42 +00:00
Adrian Prantl aac78ce47e Use helper function instead of manually constructing DBG_VALUEs (NFC)
rdar://problem/33580047

llvm-svn: 309757
2017-08-01 22:37:35 +00:00
Nirav Dave dcc5afaad9 [DAG] Factor out common expressions. NFC.
llvm-svn: 309740
2017-08-01 20:30:52 +00:00
Reid Kleckner 29c675247d [DebugInfo] Don't turn dbg.declare into DBG_VALUE for static allocas
Summary:
We already have information about static alloca stack locations in our
side table. Emitting instructions for them is inefficient, and it only
happens when the address of the alloca has been materialized within the
current block, which isn't often.

Reviewers: aprantl, probinson, dblaikie

Subscribers: jfb, dschuff, sbc100, jgravelle-google, hiraditya, llvm-commits, aheejin

Differential Revision: https://reviews.llvm.org/D36117

llvm-svn: 309729
2017-08-01 19:45:09 +00:00
Nirav Dave 35dd1ac29c Pull out VectorNumElements value. NFC.
llvm-svn: 309719
2017-08-01 18:19:56 +00:00
Nirav Dave 27a6605bdc Revert "[DAG] Extend visitSCALAR_TO_VECTOR optimization to truncated vector."
This reverts commit r309680 which appears to be raising an assertion
in the test-suite.

llvm-svn: 309717
2017-08-01 18:09:25 +00:00
Nirav Dave f54c8370e5 [DAG] Convert extload check to equivalent type check. NFC.
Replace check with check that consuming store has the same type.

llvm-svn: 309708
2017-08-01 17:19:41 +00:00
Nirav Dave b5a0af6b6e [DAG] Move extload check in store merge. NFC.
Move candidate check from later check to initial candidate check.

llvm-svn: 309698
2017-08-01 16:00:47 +00:00
Nirav Dave b5cb48c6ae [DAG] Extend visitSCALAR_TO_VECTOR optimization to truncated vector.
Summary:
Allow SCALAR_TO_VECTOR of EXTRACT_VECTOR_ELT to reduce to
EXTRACT_SUBVECTOR of vector shuffle when output is smaller. Marginally
improves vector shuffle computations.

Reviewers: efriedma, RKSimon, spatel

Subscribers: javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D35566

llvm-svn: 309680
2017-08-01 13:45:35 +00:00
Eli Friedman 37f41d1e7c [ScheduleDAG] Don't schedule node with physical register interference
https://reviews.llvm.org/D31536 didn't really solve the problem it was
trying to solve; it got rid of the assertion failure, but we were still
scheduling the DAG incorrectly (mixing together instructions from
different calls), leading to a MachineVerifier failure.

In order to schedule the DAG correctly, we have to make sure we don't
schedule a node which should be blocked by an interference. Fix
ScheduleDAGRRList::PickNodeToScheduleBottomUp so it doesn't pick a node
like that.

The added call to FindAvailableNode() is the key change here; this makes
sure we don't try to schedule a call while we're in the middle of
scheduling a different call. I'm not sure this is the right approach; in
particular, I'm not sure how to prove we don't end up with an infinite
loop of repeatedly backtracking.

This also reverts the code change from D31536. It doesn't do anything
useful: we should never schedule an ADJCALLSTACKDOWN unless we've
already scheduled the corresponding ADJCALLSTACKUP.

Differential Revision: https://reviews.llvm.org/D33818

llvm-svn: 309642
2017-08-01 00:28:40 +00:00
Simon Dardis 8930b4a049 [SelectionDAG][mips] Fix PR33883
PR33883 shows that calls to intrinsic functions should not have their vector
arguments or returns subject to ABI changes required by the target.

This resolves PR33883.

Thanks to Alex Crichton for reporting the issue!

Reviewers: zoran.jovanovic, atanasyan

Differential Revision: https://reviews.llvm.org/D35765

llvm-svn: 309561
2017-07-31 14:06:58 +00:00
Simon Pilgrim 718cb0ea62 [SelectionDAG][X86] CombineBT - more aggressively determine demanded bits
This patch is in 2 parts:

1 - replace combineBT's use of SimplifyDemandedBits (hasOneUse only) with SelectionDAG::GetDemandedBits to more aggressively determine the lower bits used by BT.

2 - update SelectionDAG::GetDemandedBits to support ANY_EXTEND - if the demanded bits are only in the non-extended portion, then peek through and demand from the source value and then ANY_EXTEND that if we found a match.

Differential Revision: https://reviews.llvm.org/D35896

llvm-svn: 309486
2017-07-29 14:50:25 +00:00
Adrian Prantl 8b9bb534a1 Remove the unused offset from DBG_VALUE (NFC)
Followup to r309426.
rdar://problem/33580047

llvm-svn: 309450
2017-07-28 23:00:45 +00:00
Adrian Prantl a617576bb1 Remove the unused dbg.value offset from SelectionDAG (NFC)
Followup to r309426.
rdar://problem/33580047

llvm-svn: 309436
2017-07-28 21:27:35 +00:00
Adrian Prantl abe04759a6 Remove the obsolete offset parameter from @llvm.dbg.value
There is no situation where this rarely-used argument cannot be
substituted with a DIExpression and removing it allows us to simplify
the DWARF backend. Note that this patch does not yet remove any of
the newly dead code.

rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D35951

llvm-svn: 309426
2017-07-28 20:21:02 +00:00
Simon Pilgrim ac84850ea6 [SelectionDAG] Improve DAGTypeLegalizer::convertMask assertion (PR33960)
Improve DAGTypeLegalizer::convertMask's isSETCCorConvertedSETCC assertion to properly check for any mixture of SETCC or BUILD_VECTOR of constants, or a logical mask op of them.

llvm-svn: 309302
2017-07-27 18:15:54 +00:00
Simon Pilgrim 64a795c5f5 [SelectionDAG] Avoid repeated calls to getNumOperands in for loop. NFCI.
llvm-svn: 309283
2017-07-27 15:42:21 +00:00
Simon Pilgrim 0d543b5921 [SelectionDAG] Tidyup mask creation. NFCI.
Assign all concat elements to UNDEF and then just replace the first element, instead of copying everything individually.

llvm-svn: 309277
2017-07-27 15:08:53 +00:00
Peter Collingbourne 081ffe2ff2 Change CallLoweringInfo::CS to be an ImmutableCallSite instead of a pointer. NFCI.
This was a use-after-free waiting to happen.

llvm-svn: 309159
2017-07-26 19:15:29 +00:00
Zvi Rackover 092f199188 DAGCombiner: Extend reduceBuildVecToTrunc to handle non-zero offset
Summary:
Adding support for combining power2-strided build_vector's where the
first build_vectori's operand is extracted from a non-zero index.

Example:

 v4i32 build_vector((extract_elt V, 1),
                    (extract_elt V, 3),
                    (extract_elt V, 5),
                    (extract_elt V, 7))
 -->
 v4i32 truncate (bitcast (shuffle<1,u,3,u,5,u,7,u> V, u) to v4i64)

Reviewers: delena, RKSimon, guyblank

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D35700

llvm-svn: 309108
2017-07-26 12:57:03 +00:00
Simon Pilgrim 6d59933175 [DAG] Move DAGCombiner::GetDemandedBits to SelectionDAG
This patch moves the DAGCombiner::GetDemandedBits function to SelectionDAG::GetDemandedBits as a first step towards making it easier for targets to get to the source of any demanded bits without the limitations of SimplifyDemandedBits.

Differential Revision: https://reviews.llvm.org/D35841

llvm-svn: 308983
2017-07-25 16:36:44 +00:00
Francois Pichet 82bf3de606 Fix endianness bug in DAGCombiner::visitTRUNCATE and visitEXTRACT_VECTOR_ELT
Summary:
Do not assume little endian architecture in DAGCombiner::visitTRUNCATE and DAGCombiner::visitEXTRACT_VECTOR_ELT.
PR33682

Reviewers: hfinkel, sdardis, RKSimon

Reviewed By: sdardis, RKSimon

Subscribers: uabelho, RKSimon, sdardis, llvm-commits

Differential Revision: https://reviews.llvm.org/D34990

llvm-svn: 308960
2017-07-25 09:40:35 +00:00
Nirav Dave 4e6dcf73f9 [DAG] Fix typo preventing some stores merges to truncated stores.
Check the actual memory type stored and not the extended value size
when considering if truncated store merge is worthwhile.

Reviewers: efriedma, RKSimon, spatel, jyknight

Reviewed By: efriedma

Subscribers: llvm-commits, nhaehnle

Differential Revision: https://reviews.llvm.org/D35623

llvm-svn: 308833
2017-07-23 02:06:28 +00:00
Xin Tong 495a3022da [DAGCombiner] Update comment. NFC
llvm-svn: 308772
2017-07-21 19:10:19 +00:00
Nirav Dave 4aa51c3af1 [DAG] Commit missed nit cleanup from r308617. NFC.
llvm-svn: 308645
2017-07-20 18:07:57 +00:00
Nirav Dave df86d2d008 [DAG] Handle missing transform in fold of value extension case.
Summary:
When pushing an extension of a constant bitwise operator on a load
into the load, change other uses of the load value if they exist to
prevent the old load from persisting.

Reviewers: spatel, RKSimon, efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D35030

llvm-svn: 308618
2017-07-20 13:57:32 +00:00
Nirav Dave 77cc6f23b9 [DAG] Optimize away degenerate INSERT_VECTOR_ELT nodes.
Summary:
Add missing vector write of vector read reduction, i.e.:

(insert_vector_elt x (extract_vector_elt x idx) idx) to x

Reviewers: spatel, RKSimon, efriedma

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D35563

llvm-svn: 308617
2017-07-20 13:48:17 +00:00
Simon Pilgrim 2911296f10 [DAGCombiner] Match ISD::SRL non-uniform constant vectors patterns using predicates.
Use predicate matchers introduced in D35492 to match more ISD::SRL constant folds

llvm-svn: 308602
2017-07-20 11:03:30 +00:00
Simon Pilgrim b9ff25df59 Remove trailing whitespace. NFCI.
llvm-svn: 308601
2017-07-20 10:43:52 +00:00
Simon Pilgrim 7ff0e49d8c [DAGCombiner] Match ISD::SRA non-uniform constant vectors patterns using predicates.
Use predicate matchers introduced in D35492 to match more ISD::SRA constant folds

llvm-svn: 308600
2017-07-20 10:43:05 +00:00
Simon Pilgrim 9d7863b935 [DAGCombiner] Match non-uniform constant vectors using predicates.
Most combines currently recognise scalar and splat-vector constants, but not non-uniform vector constants.

This patch introduces a matching mechanism that uses predicates to check against BUILD_VECTOR of ConstantSDNode, as well as scalar ConstantSDNode cases.

I've changed a couple of predicates to demonstrate - the combine-shl changes add currently unsupported cases, while the MatchRotate replaces an existing mechanism.

Differential Revision: https://reviews.llvm.org/D35492

llvm-svn: 308598
2017-07-20 10:13:40 +00:00
Simon Pilgrim c77e262260 {DAGCombine] Convert (Val & Mask) == Mask to Mask.isSubsetof(Val). NFCI.
llvm-svn: 308460
2017-07-19 13:39:58 +00:00
Nirav Dave d839749ae8 [DAG] Improve Aliasing of operations to static alloca
Re-recommiting after landing DAG extension-crash fix.

Recommiting after adding check to avoid miscomputing alias information
on addresses of the same base but different subindices.

Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.

Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.

Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.

The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.

Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand

Reviewed By: rnk

Subscribers: sdardis, nemanjai, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33345

llvm-svn: 308350
2017-07-18 20:06:24 +00:00
Nirav Dave 041b87758a [DAG] Reverse node replacement in extension operation. NFCI.
Reorder replacements to be user first in preparation for multi-level
folding to premptively avoid inadvertantly deleting later nodes from
sharing found from replacement.

llvm-svn: 308348
2017-07-18 19:49:20 +00:00
Nirav Dave 07871007aa [DAG] Avoid deleting nodes before combining them.
When replacing a node and it's operand, replacing the operand node may
cause the deletion of the original node leading to an assertion
failure. Case around these replacements to avoid this without relying
on inspecting the DELETED_NODE opcode in various extend
dagcombiner cases.

Fixes PR32515.

Reviewers: dbabokin, RKSimon, davide, chandlerc

Subscribers: chandlerc, llvm-commits

Differential Revision: https://reviews.llvm.org/D34095

llvm-svn: 308330
2017-07-18 17:39:15 +00:00
Nirav Dave f87c8e82f6 [DAG] Allow base element type of store merge type to also be a vector.
Correctly calculate merged vector size if MemVT is already a vector.

llvm-svn: 308312
2017-07-18 14:39:09 +00:00
Simon Pilgrim 4793a11df9 [DAGCombine] Fix issue with out of bound constant rotation (PR33828)
Take the modulo of rotations by a constant greater than or equal to the bit-width

llvm-svn: 308302
2017-07-18 12:31:46 +00:00
Chandler Carruth a15e080b05 Revert r308025 due to uncovering a crash in SelectionDAG. This is filed
with a minimal test case in http://llvm.org/PR33833.

Original commit message:
  Improve Aliasing of operations to static alloca

llvm-svn: 308271
2017-07-18 07:53:47 +00:00
Andrew Zhogin 67a64041b9 [DAGCombiner] Recognise vector rotations with non-splat constants
Fixes PR33691.

Differential revision: https://reviews.llvm.org/D35381

llvm-svn: 308150
2017-07-16 23:11:45 +00:00
Simon Pilgrim e7a2e6bdf1 Strip trailing whitespace. NFCI
llvm-svn: 308108
2017-07-15 19:29:19 +00:00
Nirav Dave a8f63af9d1 Improve Aliasing of operations to static alloca
Recommiting after adding check to avoid miscomputing alias information
on addresses of the same base but different subindices.

Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.

Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.

Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.

The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.

Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand

Reviewed By: rnk

Subscribers: sdardis, nemanjai, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33345

llvm-svn: 308025
2017-07-14 13:56:21 +00:00
Simon Dardis 250256f9c9 Reland "[mips] Fix multiprecision arithmetic."
For multiprecision arithmetic on MIPS, rather than using ISD::ADDE / ISD::ADDC,
get SelectionDAG to break down the operation into ISD::ADDs and ISD::SETCCs.

For MIPS, only the DSP ASE has a carry flag, so in the general case it is not
useful to directly support ISD::{ADDE, ADDC, SUBE, SUBC} nodes.

Also improve the generation code in such cases for targets with
TargetLoweringBase::ZeroOrOneBooleanContent by directly using the result of the
comparison node rather than using it in selects. Similarly for ISD::SUBE /
ISD::SUBC.

Address optimization breakage by moving the generation of MIPS specific integer
multiply-accumulate nodes to before legalization.

This revolves PR32713 and PR33424.

Thanks to Simonas Kazlauskas and Pirama Arumuga Nainar for reporting the issue!

Reviewers: slthakur

Differential Revision: https://reviews.llvm.org/D33494

The previous version of this patch was too aggressive in producing fused
integer multiple-addition instructions.

llvm-svn: 307906
2017-07-13 11:28:05 +00:00
Simon Pilgrim bb85cb16e3 [DAGCombiner] Fix issue with rotate combines asserting if the constant value types differ from the result type.
llvm-svn: 307900
2017-07-13 10:41:49 +00:00
Simon Pilgrim 2dc42b7202 Use isNullConstantOrNullSplatConstant helper. NFCI.
llvm-svn: 307895
2017-07-13 09:39:00 +00:00
Geoff Berry bea2e188e9 [TargetLowering] Add hook for adding target MMO flags when doing ISel.
Summary: Add TargetLowering hook getMMOFlags() to add target specific
MMO flags to load/store instructions created by ISel.

Reviewers: bogner, hfinkel, qcolombet, MatzeB

Subscribers: mcrosier, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D34962

llvm-svn: 307879
2017-07-13 03:49:42 +00:00
Daniel Neilson 965613ef1b Add element atomic memset intrinsic
Summary: Continuing the work from https://reviews.llvm.org/D33240, this change introduces an element unordered-atomic memset intrinsic. This intrinsic is essentially memset with the implementation requirement that all stores used for the assignment are done with unordered-atomic stores of a given element size.

Reviewers: eli.friedman, reames, mkazantsev, skatkov

Reviewed By: reames

Subscribers: jfb, dschuff, sbc100, jgravelle-google, aheejin, efriedma, llvm-commits

Differential Revision: https://reviews.llvm.org/D34885

llvm-svn: 307854
2017-07-12 21:57:23 +00:00
Daniel Neilson 57226ef33c Add element atomic memmove intrinsic
Summary: Continuing the work from https://reviews.llvm.org/D33240, this change introduces an element unordered-atomic memmove intrinsic. This intrinsic is essentially memmove with the implementation requirement that all loads/stores used for the copy are done with unordered-atomic loads/stores of a given element size.

Reviewers: eli.friedman, reames, mkazantsev, skatkov

Reviewed By: reames

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34884

llvm-svn: 307796
2017-07-12 15:25:26 +00:00
Konstantin Zhuravlyov bb80d3e1d3 Enhance synchscope representation
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
  global and local memory. These scopes restrict how synchronization is
  achieved, which can result in improved performance.

  This change extends existing notion of synchronization scopes in LLVM to
  support arbitrary scopes expressed as target-specific strings, in addition to
  the already defined scopes (single thread, system).

  The LLVM IR and MIR syntax for expressing synchronization scopes has changed
  to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
  replaces *singlethread* keyword), or a target-specific name. As before, if
  the scope is not specified, it defaults to CrossThread/System scope.

  Implementation details:
    - Mapping from synchronization scope name/string to synchronization scope id
      is stored in LLVM context;
    - CrossThread/System and SingleThread scopes are pre-defined to efficiently
      check for known scopes without comparing strings;
    - Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
      the bitcode.

Differential Revision: https://reviews.llvm.org/D21723

llvm-svn: 307722
2017-07-11 22:23:00 +00:00
Matthias Braun b38736706e Revert "[DAG] Improve Aliasing of operations to static alloca"
Reverting as it breaks tramp3d-v4 in the llvm test-suite. I added some
comments to https://reviews.llvm.org/D33345 about it.

This reverts commit r307546.

llvm-svn: 307589
2017-07-10 20:51:30 +00:00
Nirav Dave 4dcad5dc6b Add DAG argument to canMergeStoresTo NFC.
llvm-svn: 307583
2017-07-10 20:25:54 +00:00
Nirav Dave 163e1ad9dc [DAG] Improve Aliasing of operations to static alloca
Memory accesses offset from frame indices may alias, e.g., we
may merge write from function arguments passed on the stack when they
are contiguous. As a result, when checking aliasing, we consider the
underlying frame index's offset from the stack pointer.

Static allocs are realized as stack objects in SelectionDAG, but its
offset is not set until post-DAG causing DAGCombiner's alias check to
consider access to static allocas to frequently alias. Modify isAlias
to consider access between static allocas and access from other frame
objects to be considered aliasing.

Many test changes are included here. Most are fixes for tests which
indirectly relied on our aliasing ability and needed to be modified to
preserve their original intent.

The remaining tests have minor improvements due to relaxed
ordering. The exception is CodeGen/X86/2011-10-19-widen_vselect.ll
which has a minor degradation dispite though the pre-legalized DAG is
improved.

Reviewers: rnk, mkuper, jonpa, hfinkel, uweigand

Reviewed By: rnk

Subscribers: sdardis, nemanjai, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33345

llvm-svn: 307546
2017-07-10 15:39:41 +00:00
Hiroshi Inoue a86c920b1e fix typos in comments and error messages; NFC
llvm-svn: 307533
2017-07-10 12:44:25 +00:00
Davide Italiano c4b0ccd049 [X86] Relax an assertion when legalizing vector types.
WidenVSELECTAndMask can fold (and it folds in this case) so we
get a BUILD_VECTOR of constants as mask. convertMask() seems to
work fine when the input is a vector of constants, and we still
need to call it to extend/add elements at the end. but the current
code just asserts on anything but a SETCC or AND/OR/XOR of 2xSETCC.
This change was discussed briefly with Simon Pilgrim, who also
suggests we might consider dropping this assertion in the future.

Fixes PR33715.

llvm-svn: 307508
2017-07-09 19:22:48 +00:00
Simon Pilgrim 55a4b6700f Handle ConstantExpr correctly in SelectionDAGBuilder
This change fixes a bug in SelectionDAGBuilder::visitInsertValue and SelectionDAGBuilder::visitExtractValue where constant expressions (InsertValueConstantExpr and ExtractValueConstantExpr) would be treated as non-constant instructions (InsertValueInst and ExtractValueInst). This bug resulted in an incorrect memory access, which manifested as an assertion failure in SDValue::SDValue.

Fixes PR#33094.

Submitted on behalf of @Praetonus (Benoit Vey)

Differential Revision: https://reviews.llvm.org/D34538

llvm-svn: 307502
2017-07-09 16:01:04 +00:00
Igor Breger b80b44b7b9 [FastISel] fix a fallback diagnostic.
Summary: FastISel was marked as failed in case instruction selection succeeded.

Reviewers: qcolombet, zvi, rovka, ab

Reviewed By: zvi

Subscribers: javed.absar, ab, qcolombet, bogner, llvm-commits

Differential Revision: https://reviews.llvm.org/D34438

llvm-svn: 307489
2017-07-09 05:55:20 +00:00
Sanjay Patel 4cea2ec254 [DAGCombiner] use local variable to shorten code; NFCI
llvm-svn: 307429
2017-07-07 19:34:42 +00:00
Vadim Chugunov e6f76558c7 Fix libcall expansion creating DAG nodes with invalid type post type legalization.
If we are lowering a libcall after legalization, we'll split the return type into a pair of legal values.

Patch by Jatin Bhateja and Eli Friedman.

Differential Revision: https://reviews.llvm.org/D34240

llvm-svn: 307207
2017-07-05 22:01:49 +00:00
Simon Pilgrim ac78daf517 {DAGCombiner] Fold (rot x, 0) -> x
llvm-svn: 307184
2017-07-05 18:27:11 +00:00
Andrew Zhogin 45d192823e [DAGCombiner] visitRotate patch to optimize pair of ROTR/ROTL instructions into one with combined shift operand.
For two ROTR operations with shifts C1, C2; combined shift operand will be (C1 + C2) % bitsize.

Differential revision: https://reviews.llvm.org/D12833

llvm-svn: 307179
2017-07-05 17:55:42 +00:00
Nirav Dave b320ef9fab Rewrite areNonVolatileConsecutiveLoads to use BaseIndexOffset
Relanding after rewriting undef.ll test to avoid host-dependant
endianness.

As discussed in D34087, rewrite areNonVolatileConsecutiveLoads using
generic checks. Also, propagate missing local handling from there to
BaseIndexOffset checks.

Tests of note:

  * test/CodeGen/X86/build-vector* - Improved.
  * test/CodeGen/BPF/undef.ll - Improved store alignment allows an
    additional store merge

  * test/CodeGen/X86/clear_upper_vector_element_bits.ll - This is a
    case we already do not handle well. Here, the DAG is improved, but
    scheduling causes a code size degradation.

Reviewers: RKSimon, craig.topper, spatel, andreadb, filcab

Subscribers: nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D34472

llvm-svn: 307114
2017-07-05 01:21:23 +00:00
Hiroshi Inoue 79f8933f23 fix trivial typos in comments; NFC
llvm-svn: 307094
2017-07-04 16:35:26 +00:00
Andrew Zhogin de5d250a0b [DAGCombiner] Intermediate variables in visitRotate promoted to the function's begin. NFC precommit for D12833.
llvm-svn: 307091
2017-07-04 15:57:39 +00:00
Anna Thomas a66a98cc74 [FastISel][SelectionDAG]Teach fastISel about GC intrinsics
Summary:
We are crashing in LLC at O0 when gc intrinsics are present in the block.
The reason being FastISel performs basic block ISel by modifying GC.relocates
to be the first instruction in the block. This can cause us to visit the GC
relocate before it's corresponding GC.statepoint is visited, which is incorrect.
When we lower the statepoint, we record the base and derived pointers, along
with the gc.relocates. After this we can visit the gc.relocate.

This patch avoids fastISel from incorrectly creating the block with gc.relocate
as the first instruction.

Reviewers: qcolombet, skatkov, qikon, reames

Reviewed by: skatkov

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34421

llvm-svn: 307084
2017-07-04 15:09:09 +00:00
Nirav Dave a2810e677b [DAG] Fixed predicate for determining when two frame indices
addresses are comparable. NFCI.

llvm-svn: 307055
2017-07-04 02:20:17 +00:00
Anton Yartsev 66d32c5e06 [legalize-types] Clean up softening machinery.
The patch makes SoftenFloatResult/Operand logic just the same as all other legalization routines have: SoftenFloatResult() now fills the SoftenFloats map and SoftenFloatOperand() perform all needed replacements. This prevents softening mashinery from leaving stale entries in SoftenFloats map (that resulted in errors during the legalize type checking) and clarifies softening. The patch replaces https://reviews.llvm.org/D29265.

Differential Revision: https://reviews.llvm.org/D31946

llvm-svn: 307053
2017-07-04 01:08:55 +00:00
Zvi Rackover d7a1c334ce DAGCombine: Combine BUILD_VECTOR to TRUNCATE
Summary:
Add a combine for creating a truncate to replace a build_vector composed of extracts with
indices that form a stride-2^N series.

Example:
v8i32 V = ...

v4i32 build_vector((extract_elt V, 0), (extract_elt V, 2), (extract_elt V, 4), (extract_elt V, 6))
-->
v4i32 truncate (bitcast V to v4i64)

Related discussion in llvm-dev about canonicalizing shuffles to
truncates in LLVM IR:
http://lists.llvm.org/pipermail/llvm-dev/2017-January/108936.html.

Reviewers: spatel, RKSimon, efriedma, igorb, craig.topper, wolfgangp, delena

Reviewed By: delena

Subscribers: guyblank, delena, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D34077

llvm-svn: 307036
2017-07-03 15:47:40 +00:00
Craig Topper 92a8fe34e5 [SelectionDAGBuilder] Use EVT::getVectorVT instead of MVT::getVectorVT to prevent a crash if the type isn't a simple VT.
llvm-svn: 306950
2017-07-01 06:46:09 +00:00
Nirav Dave a35938d827 Revert "[DAG] Rewrite areNonVolatileConsecutiveLoads to use BaseIndexOffset"
This reverts commit r306819 which appears be exposing underlying
issues in a stage1 ppc64be build

llvm-svn: 306820
2017-06-30 12:56:02 +00:00
Nirav Dave c5a48c1ee8 [DAG] Rewrite areNonVolatileConsecutiveLoads to use BaseIndexOffset
As discussed in D34087, rewrite areNonVolatileConsecutiveLoads using
generic checks. Also, propagate missing local handling from there to
BaseIndexOffset checks.

Tests of note:

  * test/CodeGen/X86/build-vector* - Improved.
  * test/CodeGen/BPF/undef.ll - Improved store alignment allows an
    additional store merge

  * test/CodeGen/X86/clear_upper_vector_element_bits.ll - This is a
    case we already do not handle well. Here, the DAG is improved, but
    scheduling causes a code size degradation.

Reviewers: RKSimon, craig.topper, spatel, andreadb, filcab

Subscribers: nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D34472

llvm-svn: 306819
2017-06-30 12:23:41 +00:00
Simon Dardis dede76f428 Revert "[mips] Fix multiprecision arithmetic."
This reverts commit r305389. This broke chromium builds, so reverting
while I investigate further.

llvm-svn: 306741
2017-06-29 20:59:47 +00:00
Nirav Dave 168c5a6a40 [DAG] Fold FrameIndex offset into BaseIndexOffset analysis. NFCI.
Relanding after restricting equalBaseIndex to not erroneuosly consider
a FrameIndices stemming from alloca from being comparable as its
offset is set post-selectionDAG.

Pull FrameIndex comparision reasoning from DAGCombiner::isAlias to
general BaseIndexOffset.

llvm-svn: 306688
2017-06-29 15:48:11 +00:00
Stanislav Mekhanoshin a45584bebe Fold fneg and fabs like multiplications
Given no NaNs and no signed zeroes it folds:

(fmul X, (select (fcmp X > 0.0), -1.0, 1.0)) -> (fneg (fabs X))
(fmul X, (select (fcmp X > 0.0), 1.0, -1.0)) -> (fabs X)

Differential Revision: https://reviews.llvm.org/D34579

llvm-svn: 306592
2017-06-28 20:25:50 +00:00
Nirav Dave c4ce2293b0 Revert "[DAG] Fold FrameIndex offset into BaseIndexOffset analysis. NFCI."
This reverts commit r306498 which appears to cause a compilrt-rt test failures

llvm-svn: 306501
2017-06-28 03:20:04 +00:00
Stanislav Mekhanoshin eb40733bf0 Allow to truncate left shift with non-constant shift amount
That is pretty common for clang to produce code like
(shl %x, (and %amt, 31)). In this situation we can still perform
trunc (shl) into shl (trunc) conversion given the known value
range of shift amount.

Differential Revision: https://reviews.llvm.org/D34723

llvm-svn: 306499
2017-06-28 02:37:11 +00:00
Nirav Dave 8ef03802f1 [DAG] Fold FrameIndex offset into BaseIndexOffset analysis. NFCI.
Pull FrameIndex comparision reasoning from DAGCombiner::isAlias to
general BaseIndexOffset.

llvm-svn: 306498
2017-06-28 02:09:50 +00:00
Hiroshi Inoue 84aafee4fb [SelectionDAG] set dereferenceable flag in MergeConsecutiveStores to fix assetion failure
When SelectionDAG merges consecutive stores and loads in MergeConsecutiveStores, it does not set dereferenceable flag for a created load instruction. This results in an assertion failure if SelectionDAG commonizes this load instruction with other load instructions, as well as it may miss optimization opportunities.

This patch sat dereferenceable flag for the newly created load instruction if all the load instructions to be merged are dereferenceable.

Differential Revision: https://reviews.llvm.org/D34679

llvm-svn: 306404
2017-06-27 12:43:08 +00:00
Wolfgang Pieb 9f65858235 DAGCombine: Make sure we only eliminate trunc/extend when the scales of truncation and extension match.
This fixes PR33368.

Reviewer: rksimon

Differential Revision:  https://reviews.llvm.org/D34069

llvm-svn: 306345
2017-06-26 23:05:51 +00:00
Elena Demikhovsky 72f991cded AVX-512: Fixed a crash during legalization of <3 x i8> type
The compiler fails with assertion during legalization of SETCC for <3 x i8> operands.
The result is extended to <4 x i8> and then truncated <4 x i1>. It does not happen on AVX2, because the final result of SETCC is <4 x i32>.

Differential Revision: https://reviews.llvm.org/D34503

llvm-svn: 306242
2017-06-25 13:36:20 +00:00
Hiroshi Inoue 95f24dca98 [SelectionDAG] set dereferenceable flag when expanding memcpy/memmove
When SelectionDAG expands memcpy (or memmove) call into a sequence of load and store instructions, it disregards dereferenceable flag even the source pointer is known to be dereferenceable.
This results in an assertion failure if SelectionDAG commonizes a load instruction generated for memcpy with another load instruction for the source pointer.
This patch makes SelectionDAG to set the dereferenceable flag for the load instructions properly to avoid the assertion failure.

Differential Revision: https://reviews.llvm.org/D34467

llvm-svn: 306209
2017-06-24 15:17:38 +00:00
Nirav Dave f2c349ccec [DAG] Add Target Store Merge pass ordering function
Allow targets to specify if they should merge stores before or after
legalization.

llvm-svn: 306006
2017-06-22 15:07:49 +00:00
Nirav Dave c1b6aa77bb [DAG] Move BaseIndexOffset into separate Libarary. NFC.
Move BaseIndexOffset analysis out of DAGCombiner for use in other
files.

llvm-svn: 305921
2017-06-21 15:40:43 +00:00
Nirav Dave 9a69d444a3 [DAG] Remove Node csonstruction from BaseIndexOffset match. NFCI.
Move GlobalAddress Offset decomposition from initial match into
comparision check and removing the possibility of constructing a new
offseted global address when examining addresses.

llvm-svn: 305917
2017-06-21 15:07:30 +00:00
Guy Blank 52d73fce85 [DAGCombiner] Add another combine from build vector to shuffle
Add support for combining a build vector to a shuffle.
When the build vector is of extracted elements from 2 vectors (vec1, vec2) where vec2 is 2 times smaller than vec1.

llvm-svn: 305883
2017-06-21 07:38:41 +00:00
Tim Northover 208ddc5bdc DAG: correctly legalize UMULO.
We were incorrectly sign extending into the high word (as you would for
SMULO) when legalizing UMULO in terms of a wider full multiplication.

Patch by James Duley.

llvm-svn: 305800
2017-06-20 15:01:38 +00:00
Haojian Wu 6bd5cc6239 [SelectionDAG] Fix an use-after-free issue introduced in r305775.
vector.back() will be invalidated when memory reallocation happens.

llvm-svn: 305785
2017-06-20 09:29:43 +00:00
Max Kazantsev b5c3362873 [SelectionDAG] Get rid of recursion in CalcNodeSethiUllmanNumber
The recursive implementation of CalcNodeSethiUllmanNumber may
overflow stack on extremely long pred chains. This patch replaces it
with an equivalent iterative implementation.

Differential Revision: https://reviews.llvm.org/D33769

llvm-svn: 305775
2017-06-20 07:07:09 +00:00
Nirav Dave 47a78a2502 [DAG] Simplify BaseIndexOffset. NFCI.
Remove tail calls and cleanup codeflow.

llvm-svn: 305768
2017-06-20 02:48:39 +00:00
Nirav Dave 8dcd008d18 Allow truncated and extend memory operations in Store Merge. NFCI.
As all store merges checks are based on the memory operation
performed, allow use of truncated stores and extended loads as valid
input candidates for merging.

Relanding after fixing selection between truncated and normal store.

llvm-svn: 305701
2017-06-19 15:32:28 +00:00
Davide Italiano 9382c5560b [SelectionDAG] Update Loop info after splitting critical edges.
The analysis is expected to be preserved by SelectionDAG.

llvm-svn: 305621
2017-06-17 00:56:27 +00:00
Craig Topper 288b3c9e69 [SelectionDAG] Use APInt::isSubsetOf. NFC
llvm-svn: 305606
2017-06-16 23:19:14 +00:00
Craig Topper ea5b8bc9ef [SelectionDAG] Use APInt::isNullValue/isOneValue. NFC
llvm-svn: 305605
2017-06-16 23:19:12 +00:00
Craig Topper b681907c50 [TargetLowering] Use ConstantSDNode::isOne and getSExtValue instead of getting the underlying APInt first. NFC
llvm-svn: 305604
2017-06-16 23:19:10 +00:00
Daniel Neilson 3faabbbe85 [Atomics] Rename and change prototype for atomic memcpy intrinsic
Summary:

Background: http://lists.llvm.org/pipermail/llvm-dev/2017-May/112779.html

This change is to alter the prototype for the atomic memcpy intrinsic. The prototype itself is being changed to more closely resemble the semantics and parameters of the llvm.memcpy intrinsic -- to ease later combination of the llvm.memcpy and atomic memcpy intrinsics. Furthermore, the name of the atomic memcpy intrinsic is being changed to make it clear that it is not a generic atomic memcpy, but specifically a memcpy is unordered atomic.

Reviewers: reames, sanjoy, efriedma

Reviewed By: reames

Subscribers: mzolotukhin, anna, llvm-commits, skatkov

Differential Revision: https://reviews.llvm.org/D33240

llvm-svn: 305558
2017-06-16 14:43:59 +00:00
Ahmed Bougacha d41a9c4e66 Revert "[DAG] Allow truncated and extend memory operations in Store Merge. NFCI."
This reverts commit r305468, as it caused PR33475.

llvm-svn: 305527
2017-06-15 23:29:47 +00:00
Benjamin Kramer 00a970a84b Fold variable into assert.
Silences an unused variable warning in Release builds.

llvm-svn: 305488
2017-06-15 17:58:24 +00:00
Arnold Schwaighofer ae9312c487 ISel: Fix FastISel of swifterror values
The code assumed that we process instructions in basic block order.  FastISel
processes instructions in reverse basic block order. We need to pre-assign
virtual registers before selecting otherwise we get def-use relationships wrong.

This only affects code with swifterror registers.

rdar://32659327

llvm-svn: 305484
2017-06-15 17:34:42 +00:00
Nirav Dave 9d79cade42 [DAG] As StoreMerge now generates only legal nodes remove unecessary guard when run post-legalization NFCI.
llvm-svn: 305477
2017-06-15 16:27:49 +00:00
Nirav Dave be2674a598 [DAG] Defer Pre/Post IndexStore merge to after mergestore. NFCI.
In preparation for doing storemerge post-legalization, reorder
visitSTORE passes to move pre/post-index combining after store
merge. Reordered passes other than store merge are unaffected.

llvm-svn: 305473
2017-06-15 15:05:48 +00:00
Nirav Dave 9464c72850 [DAG] Allow truncated and extend memory operations in Store Merge. NFCI.
As all store merges checks are based on the memory operation
performed, allow use of truncated stores and extended loads as valid
input candidates for merging.

llvm-svn: 305468
2017-06-15 14:04:07 +00:00
Nirav Dave 6a41822ba7 [DAG] Make MergeStores generate legalized stores. NFCI.
Realized merged stores as truncstores if store will be realized as
such by legalization.

llvm-svn: 305467
2017-06-15 13:34:54 +00:00
Nirav Dave 9a4998980d [DAG] Use correct size for truncated store merge of load. NFCI.
Avoid non-legal memory ops by checking correct size when merging
stores of loads into a extload-truncstore pair.

llvm-svn: 305466
2017-06-15 13:28:06 +00:00
Simon Dardis 9790e39f45 [mips] Fix multiprecision arithmetic.
For multiprecision arithmetic on MIPS, rather than using ISD::ADDE / ISD::ADDC,
get SelectionDAG to break down the operation into ISD::ADDs and ISD::SETCCs.

For MIPS, only the DSP ASE has a carry flag, so in the general case it is not
useful to directly support ISD::{ADDE, ADDC, SUBE, SUBC} nodes.

Also improve the generation code in such cases for targets with
TargetLoweringBase::ZeroOrOneBooleanContent by directly using the result of the
comparison node rather than using it in selects. Similarly for ISD::SUBE /
ISD::SUBC.

Address optimization breakage by moving the generation of MIPS specific integer
multiply-accumulate nodes to before legalization.

This revolves PR32713 and PR33424.

Thanks to Simonas Kazlauskas and Pirama Arumuga Nainar for reporting the issue!

Reviewers: slthakur

Differential Revision: https://reviews.llvm.org/D33494

llvm-svn: 305389
2017-06-14 14:46:30 +00:00
Geoff Berry 06c9dc3d9c [SelectionDAG] Allow sin/cos -> sincos optimization on GNU triples w/ just -fno-math-errno
Summary:
This change enables the sin(x) cos(x) -> sincos(x) optimization on GNU
target triples.  This optimization was being inhibited when -ffast-math
wasn't set because sincos in GLibC does not set errno, while sin and cos
do.  However, this optimization will only run if the attributes on the
sin/cos calls include readnone, which is how clang represents the fact
that it doesn't care about the errno values set by these functions (via
the -fno-math-errno flag).

Reviewers: hfinkel, bogner

Subscribers: mcrosier, javed.absar, llvm-commits, paul.redmond

Differential Revision: https://reviews.llvm.org/D32921

llvm-svn: 305204
2017-06-12 17:15:41 +00:00
Sanjay Patel d4765a38b4 [DAG] add helper to bind memop chains; NFCI
This step is just intended to reduce code duplication rather than change any functionality.

A follow-up would be to replace PPCTargetLowering::spliceIntoChain() usage with this new helper.

Differential Revision: https://reviews.llvm.org/D33649

llvm-svn: 305192
2017-06-12 14:41:48 +00:00
Amaury Sechet 2127452ff7 [DAGCombine] Make sure we check the ResNo from UADDO before combining
Summary: UADDO has 2 result, and one must check the result no before doing any kind of combine. Without it, the transform is invalid.

Reviewers: joerg

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D34088

llvm-svn: 305162
2017-06-11 11:36:38 +00:00
Zvi Rackover 3a2c4b48bb SelectionDAG: Remove deleted nodes from legalized set to avoid clash with newly created nodes
Summary:
During DAG legalization loop in SelectionDAG::Legalize(),
bookkeeping of the SDNodes that were already legalized is implemented
with SmallPtrSet (LegalizedNodes). This kind of set stores only pointers
to objects, not the objects themselves. Unfortunately, if SDNode is
deleted during legalization for some reason, LegalizedNodes set is not
informed about this fact. This wouldn’t be so bad, if SelectionDAG wouldn’t reuse
space deallocated after deletion of unused nodes, for creation of new
ones. Because of this, new nodes, created during legalization often can
have pointers identical to ones that have been previously legalized,
added to the LegalizedNodes set, and deleted afterwards. This in turn
causes, that newly created nodes, sharing the same pointer as deleted
old ones, are present in LegalizedNodes *already at the moment of
creation*, so we never call Legalize on them.
The fix facilitates the fact, that DAG notifies listeners about each
modification. I have registered DAGNodeDeletedListener inside
SelectionDAG::Legalize, with a callback function that removes any
pointer of any deleted SDNode from the LegalizedNodes set. With this
modification, LegalizeNodes set does not contain pointers to nodes that
were deleted, so newly created nodes can always be inserted to it, even
if they share pointers with old deleted nodes.

Patch by pawel.szczerbuk@intel.com

The issue this patch addresses causes failures in an out-of-tree target,
and i was not able to create a reproducer for an in-tree target, hence
there is no test-case.

Reviewers: delena, spatel, RKSimon, hfinkel, davide, qcolombet

Reviewed By: delena

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33891

llvm-svn: 305084
2017-06-09 14:53:45 +00:00
Simon Dardis 212cccb2f4 Reland "[SelectionDAG] Enable target specific vector scalarization of calls and returns"
By target hookifying getRegisterType, getNumRegisters, getVectorBreakdown,
backends can request that LLVM to scalarize vector types for calls
and returns.

The MIPS vector ABI requires that vector arguments and returns are passed in
integer registers. With SelectionDAG's new hooks, the MIPS backend can now
handle LLVM-IR with vector types in calls and returns. E.g.
'call @foo(<4 x i32> %4)'.

Previously these cases would be scalarized for the MIPS O32/N32/N64 ABI for
calls and returns if vector types were not legal. If vector types were legal,
a single 128bit vector argument would be assigned to a single 32 bit / 64 bit
integer register.

By teaching the MIPS backend to inspect the original types, it can now
implement the MIPS vector ABI which requires a particular method of
scalarizing vectors.

Previously, the MIPS backend relied on clang to scalarize types such as "call
@foo(<4 x float> %a) into "call @foo(i32 inreg %1, i32 inreg %2, i32 inreg %3,
i32 inreg %4)".

This patch enables the MIPS backend to take either form for vector types.

The previous version of this patch had a "conditional move or jump depends on
uninitialized value".

Reviewers: zoran.jovanovic, jaydeep, vkalintiris, slthakur

Differential Revision: https://reviews.llvm.org/D27845

llvm-svn: 305083
2017-06-09 14:37:08 +00:00
Nirav Dave 43a4d8122f Prevent RemoveDeadNodes from deleted already deleted node.
This prevents against assertion errors like PR32659 which occur from a
replacement deleting a node after it's been added to the list argument
of RemoveDeadNodes. The specific failure from PR32659 does not
currently happen, but it is still potentially possible. The underlying
cause is that the callers of the change dfunction builds up a list of
nodes to delete after having moved their uses and it possible that a
move of a later node will cause a previously deleted nodes to be
deleted.

Reviewers: bkramer, spatel, davide

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33731

llvm-svn: 305070
2017-06-09 12:57:35 +00:00
Eugene Zelenko 6ac7a34816 [CodeGen] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 304954
2017-06-07 23:53:32 +00:00
Nirav Dave 772ea3ae1a [DAG] Improve Store Merge candidate pruning. NFC.
When considering merging stores values are the results of loads only
consider stores whose values come from loads from the same base.

This fixes much of the longer compile times in PR33330.

llvm-svn: 304934
2017-06-07 18:51:56 +00:00
Simon Pilgrim be8866f691 [DAG] Move SelectionDAG::isCommutativeBinOp to TargetLowering.
This will allow commutation of target-specific DAG nodes in future patches

Differential Revision: https://reviews.llvm.org/D33882

llvm-svn: 304911
2017-06-07 14:05:04 +00:00
Sanjay Patel 2726ea2ac0 [DAG] remove duplicated code for isOnlyUsedInZeroEqualityComparison(); NFCI
llvm-svn: 304822
2017-06-06 19:40:09 +00:00
Chandler Carruth 6bda14b313 Sort the remaining #include lines in include/... and lib/....
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.

I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.

This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.

Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).

llvm-svn: 304787
2017-06-06 11:49:48 +00:00
Mandeep Singh Grang 5e1697ef28 [llvm] Remove double semicolons
Reviewers: craig.topper, arsenm, mehdi_amini

Reviewed By: mehdi_amini

Subscribers: mehdi_amini, wdng, nhaehnle, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33924

llvm-svn: 304767
2017-06-06 05:08:36 +00:00
Davide Italiano fb4d5c095b [SelectionDAG] Update the dominator after splitting critical edges.
Running `llc -verify-dom-info` on the attached testcase results in a
crash in the verifier, due to a stale dominator tree.

i.e.

  DominatorTree is not up to date!
  Computed:
  =============================--------------------------------
  Inorder Dominator Tree:
    [1] %safe_mod_func_uint8_t_u_u.exit.i.i.i {0,7}
      [2] %lor.lhs.false.i61.i.i.i {1,2}
      [2] %safe_mod_func_int8_t_s_s.exit.i.i.i {3,6}
        [3] %safe_div_func_int64_t_s_s.exit66.i.i.i {4,5}

  Actual:
  =============================--------------------------------
  Inorder Dominator Tree:
    [1] %safe_mod_func_uint8_t_u_u.exit.i.i.i {0,9}
      [2] %lor.lhs.false.i61.i.i.i {1,2}
      [2] %safe_mod_func_int8_t_s_s.exit.i.i.i {3,8}
        [3] %safe_div_func_int64_t_s_s.exit66.i.i.i {4,5}
        [3] %safe_mod_func_int8_t_s_s.exit.i.i.i.lor.lhs.false.i61.i.i.i_crit_edge {6,7}

This is because in `SelectionDAGIsel` we split critical edges without
updating the corresponding dominator for the function (and we claim
in `MachineFunctionPass::getAnalysisUsage()` that the domtree is preserved).

We could either stop preserving the domtree in `getAnalysisUsage`
or tell `splitCriticalEdge()` to update it.
As the second option is easy to implement, that's the one I chose.

Differential Revision:  https://reviews.llvm.org/D33800

llvm-svn: 304742
2017-06-05 22:16:41 +00:00
Sanjay Patel 6350de76fa [DAGCombine] Fix unchecked calls to DAGCombiner::*ExtPromoteOperand
Other calls to DAGCombiner::*PromoteOperand check the result, but here it could cause an assertion in getNode. 
Falling back to any extend in this case instead of failing outright seems correct to me.

No test case because:
The failure was triggered by an out of tree backend. In order to trigger it, a backend would need to overload 
TargetLowering::IsDesirableToPromoteOp to return true for a type for which ISD::SIGN_EXTEND_INREG is marked 
illegal. In tree, only X86 overloads and sometimes returns true for MVT::i16 yet it marks 
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16  , Legal);.

Patch by Jacob Young!

Differential Revision: https://reviews.llvm.org/D33633

llvm-svn: 304723
2017-06-05 17:01:10 +00:00
Galina Kistanova bd79f73f02 Added LLVM_FALLTHROUGH to address warning: this statement may fall through. NFC.
llvm-svn: 304635
2017-06-03 05:11:14 +00:00
Eugene Zelenko c85638b29d [CodeGen] Fix Windows builds which treat warnings as errors, broken in r304621.
llvm-svn: 304627
2017-06-03 01:04:06 +00:00
Eugene Zelenko 167595ab51 [CodeGen] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 304621
2017-06-03 00:22:41 +00:00
Philip Reames b70cecd60a [Statepoint] Be consistent about using deopt naming [NFCI]
We'd called this "vm state" in the early days, but have long since standardized on calling it "deopt" in line with the operand bundle tag.  Fix a few cases we'd missed.

llvm-svn: 304607
2017-06-02 23:03:26 +00:00
Sanjay Patel cdb5dad4cc [TargetLowering] fix formatting; NFC
llvm-svn: 304569
2017-06-02 17:35:02 +00:00
Amaury Sechet 437f7060fe nits in TargetLowering.cpp . NFC
llvm-svn: 304532
2017-06-02 09:18:18 +00:00
Max Kazantsev 4d8748a987 [SelectionDAG] Get rid of recursion in findNonImmUse
The recursive implementation of findNonImmUse may overflow stack
on extremely long use chains. This patch replaces it with an equivalent
iterative implementation.

Reviewed By: bogner

Differential Revision: https://reviews.llvm.org/D33775

llvm-svn: 304522
2017-06-02 07:11:00 +00:00
Nirav Dave 4952871630 [SDAG] Fix CombineTo ordering in visitZERO_EXTEND and visitSIGN_EXTEND
Reorder CombineTo Calls to prevent references to stale/deleted SDNodes which caused undue assertions.

Reviewers: dbabokin

Subscribers: aemerson, rengolin, llvm-commits

Differential Revision: https://reviews.llvm.org/D31625

llvm-svn: 304460
2017-06-01 19:33:50 +00:00
Matt Arsenault b083570532 DAG: Remove pointless type check
These are only integer operations.

llvm-svn: 304417
2017-06-01 14:49:46 +00:00
Amaury Sechet c84cc230b3 Only generate addcarry node when it is legal.
Summary:
This is a problem uncovered by stage2 testing. ADDCARRY end up being generated on target that do not support it.

The patch that introduced the problem has other patches layed on top of it, so we want to fix the issue rather than revert it to avoid creating a lor of churn.

A regression test will be added shortly, but this is committed as this in order to get the build back to green promptly.

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33770

llvm-svn: 304409
2017-06-01 12:03:16 +00:00
Amaury Sechet 251ea8a4f8 Do not legalize large setcc with setcce, introduce setcccarry and do it with usubo/setcccarry.
Summary:
This is a continuation of the work started in D29872 . Passing the carry down as a value rather than as a glue allows for further optimizations. Introducing setcccarry makes the use of addc/subc unecessary and we can start the removal process.

This patch only introduce the optimization strictly required to get the same level of optimization as was available before nothing more.

Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33374

llvm-svn: 304404
2017-06-01 11:14:17 +00:00
Amaury Sechet 9c5d1e966b [DAGCombine] Refactor common addcarry pattern.
Summary: This pattern is no very useful per se, but it exposes optimization for toehr patterns that wouldn't kick in otherwize. It's very common and worth optimizing for.

Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32756

llvm-svn: 304402
2017-06-01 10:48:04 +00:00
Amaury Sechet 2e43cb6d03 [DAGCombine] (add/uaddo X, Carry) -> (addcarry X, 0, Carry)
Summary:
This enables further transforms.

Depends on D32916

Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32925

llvm-svn: 304401
2017-06-01 10:42:39 +00:00
Nirav Dave 3424373f30 [ScheduleDAG] Deal with already scheduled loads in ScheduleDAG.
Summary:
If we attempt to unfold an SUnit in ScheduleDAG that results in
finding an already scheduled load, we must should abort the
unfold as it will not improve scheduling.

This fixes PR32610.

Reviewers: jmolloy, sunfish, bogner, spatel

Subscribers: llvm-commits, MatzeB

Differential Revision: https://reviews.llvm.org/D32911

llvm-svn: 304321
2017-05-31 18:43:17 +00:00
Nirav Dave 7c70fddba6 [DAG] Avoid use of stale store.
Correct references to alignment of store which may be deleted in a
previous iteration of merge. Instead use first store that would be
merged.

Corrects pr33172's use-after-poison caught by ASan.

Reviewers: spatel, hfinkel, RKSimon

Reviewed By: RKSimon

Subscribers: thegameg, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33686

llvm-svn: 304299
2017-05-31 13:36:17 +00:00
Craig Topper 5fd588be34 [SelectionDAG] Remove special case for ISD::FPOWI from the strict FP intrinsic handling.
This code was compensating for FPOWI defaulting to Legal and many targets not changing it to Expand. This was fixed in r304215 to default to Expand so this special handling should no longer be necessary.

llvm-svn: 304221
2017-05-30 17:12:18 +00:00
Craig Topper f6d4dc5b4a [SelectionDAG] Set ISD::FPOWI to Expand by default
Summary:
Currently FPOWI defaults to Legal and LegalizeDAG.cpp turns Legal into Expand for this opcode because Legal is a "lie".

This patch changes the default for this opcode to Expand and removes the hack from LegalizeDAG.cpp. It also removes all the code in the targets that set this opcode to Expand themselves since they can just rely on the default.

Reviewers: spatel, RKSimon, efriedma

Reviewed By: RKSimon

Subscribers: jfb, dschuff, sbc100, jgravelle-google, nemanjai, javed.absar, andrew.w.kaylor, llvm-commits

Differential Revision: https://reviews.llvm.org/D33530

llvm-svn: 304215
2017-05-30 15:27:55 +00:00
Sanjay Patel 51152a3727 [DAGCombiner] fix load narrowing transform to exclude loads with extension
The extending load possibility was missed in:
https://reviews.llvm.org/rL304072

We might want to handle this cases as a follow-up, but bailing out for now
to avoid miscompiling.

llvm-svn: 304153
2017-05-29 13:24:58 +00:00
Sanjay Patel 33f4a97287 [DAGCombiner] use narrow load to avoid vector extract
If we have (extract_subvector(load wide vector)) with no other users, 
that can just be (load narrow vector). This is intentionally conservative.
Follow-ups may loosen the one-use constraint to account for the extract cost
or just remove the one-use check.

The memop chain updating is based on code that already exists multiple times
in x86 lowering, so that should be pulled into a helper function as a follow-up.

Background: this is a potential improvement noticed via regressions caused by
making x86's peekThroughBitcasts() not loop on consecutive bitcasts (see 
comments in D33137).

Differential Revision: https://reviews.llvm.org/D33578

llvm-svn: 304072
2017-05-27 14:07:03 +00:00
Benjamin Kramer debb3c35e0 Make helper functions static. NFC.
llvm-svn: 304029
2017-05-26 20:09:00 +00:00
Sanjay Patel ec13ebf2c8 [DAGCombiner] use narrow vector ops to eliminate concat/extract (PR32790)
In the best case:
extract (binop (concat X1, X2), (concat Y1, Y2)), N --> binop XN, YN
...we kill all of the extract/concat and just have narrow binops remaining.

If only one of the binop operands is amenable, this transform is still
worthwhile because we kill some of the extract/concat.

Optional bitcasting makes the code more complicated, but there doesn't
seem to be a way to avoid that.

The TODO about extending to more than bitwise logic is there because we really
will regress several x86 tests including madd, psad, and even a plain
integer-multiply-by-2 or shift-left-by-1. I don't think there's anything
fundamentally wrong with this patch that would cause those regressions; those
folds are just missing or brittle.

If we extend to more binops, I found that this patch will fire on at least one
non-x86 regression test. There's an ARM NEON test in
test/CodeGen/ARM/coalesce-subregs.ll with a pattern like:

            t5: v2f32 = vector_shuffle<0,3> t2, t4
          t6: v1i64 = bitcast t5
          t8: v1i64 = BUILD_VECTOR Constant:i64<0>
        t9: v2i64 = concat_vectors t6, t8
      t10: v4f32 = bitcast t9
    t12: v4f32 = fmul t11, t10
  t13: v2i64 = bitcast t12
t16: v1i64 = extract_subvector t13, Constant:i32<0>

There was no functional change in the codegen from this transform from what I
could see though.

For the x86 test changes:

1. PR32790() is the closest call. We don't reduce the AVX1 instruction count in that case,
   but we improve throughput. Also, on a core like Jaguar that double-pumps 256-bit ops,
   there's an unseen win because two 128-bit ops have the same cost as the wider 256-bit op.
   SSE/AVX2/AXV512 are not affected which is expected because only AVX1 has the extract/concat
   ops to match the pattern.
2. do_not_use_256bit_op() is the best case. Everyone wins by avoiding the concat/extract.
   Related bug for IR filed as: https://bugs.llvm.org/show_bug.cgi?id=33026
3. The SSE diffs in vector-trunc-math.ll are just scheduling/RA, so nothing real AFAICT.
4. The AVX1 diffs in vector-tzcnt-256.ll are all the same pattern: we reduced the instruction
   count by one in each case by eliminating two insert/extract while adding one narrower logic op.

https://bugs.llvm.org/show_bug.cgi?id=32790

Differential Revision: https://reviews.llvm.org/D33137

llvm-svn: 303997
2017-05-26 15:33:18 +00:00
Nirav Dave 689709c928 [DAG] Move legal type checks in store merge to be checked only
on non-legal cases. NFC.

llvm-svn: 303994
2017-05-26 14:37:27 +00:00
John Brawn 9009d2905d [ARM] Fix lowering of misaligned memcpy/memset
Currently getOptimalMemOpType returns i32 for large enough sizes without
checking for alignment, leading to poor code generation when misaligned accesses
aren't permitted as we generate a word store then later split it up into byte
stores. This means we inadvertantly go over the MaxStoresPerMemcpy limit and for
memset we splat the memset value into a word then immediately split it up
again.

Fix this by leaving it up to FindOptimalMemOpLowering to figure out which type
to use, but also fix a bug there where it wasn't correctly checking if
misaligned memory accesses are allowed.

Differential Revision: https://reviews.llvm.org/D33442

llvm-svn: 303990
2017-05-26 13:59:12 +00:00
Andrew Kaylor f466001eef Add constrained intrinsics for some libm-equivalent operations
Differential revision: https://reviews.llvm.org/D32319

llvm-svn: 303922
2017-05-25 21:31:00 +00:00
Adrian Prantl f062192632 Fix SelectionDAGBuilder::getDbgValue to not expect DW_OP_deref on FI vars
This fixes an oversight in r300522, which changed alloca
dbg.values to no longer emit a DW_OP_deref.

The array.ll testcase was regenerated from source.

Fixes PR33166:
https://bugs.llvm.org/show_bug.cgi?id=33166

llvm-svn: 303897
2017-05-25 18:54:10 +00:00
Nirav Dave 7a8717d216 [DAG] Prevent crashes when merging constant stores with high-bit set. NFC.
llvm-svn: 303802
2017-05-24 19:56:39 +00:00
Tim Northover 8c605c0eda Revert LLVM changes for "Sema: allow imaginary constants via GNU extension if UDL overloads not present."
The changes accidentally crept into a Clang commit I was making.

llvm-svn: 303697
2017-05-23 21:53:11 +00:00
Tim Northover 6b5eceac2e Sema: allow imaginary constants via GNU extension if UDL overloads not present.
C++14 added user-defined literal support for complex numbers so that you can
write something like "complex<double> val = 2i". However, there is an existing
GNU extension supporting this syntax and interpreting the result as a _Complex
type.

This changes parsing so that such literals are interpreted in terms of C++14's
operators if an overload is present but otherwise falls back to the original
GNU extension.

llvm-svn: 303694
2017-05-23 21:41:49 +00:00
Nirav Dave 6c910c0dd8 [DAG] Add AddressSpace parameter to canMergeStoresTo. NFC.
llvm-svn: 303673
2017-05-23 18:53:02 +00:00
Nirav Dave 3b4f7cc0b3 [DAG] Add canMergeStoresTo predicate checks. NFCI.
Propagate canMergeStoresTo checks to missing cases in StoreMerge.

llvm-svn: 303668
2017-05-23 18:33:09 +00:00
Craig Topper 7e0aeeb884 [KnownBits] Use !hasConflict() in asserts in place of Zero & One == 0 or similar. NFC
llvm-svn: 303614
2017-05-23 07:18:37 +00:00
Nirav Dave e00da22ef3 [DAG] Rework store merge to loop on load candidates. NFCI.
Continue to consider remaining candidate merges until all possible
merges have been considered.

llvm-svn: 303560
2017-05-22 15:33:47 +00:00
Matthias Braun 50ec0b5dce SimplifyLibCalls: Optimize wcslen
Refactor the strlen optimization code to work for both strlen and wcslen.

This especially helps with programs in the wild where people pass
L"string"s to const std::wstring& function parameters and the wstring
constructor gets inlined.

This also fixes a lingerind API problem/bug in getConstantStringInfo()
where zeroinitializers would always give you an empty string (without a
length) back regardless of the actual length of the initializer which
did not work well in the TrimAtNul==false causing the PR mentioned
below.

Note that the fixed getConstantStringInfo() needed fixes to SelectionDAG
memcpy lowering and may lead to some cases for out-of-bounds
zeroinitializer accesses not getting optimized anymore. So some code
with UB may produce out of bound memory reads now instead of just
producing zeros.

The refactoring "accidentally" fixes http://llvm.org/PR32124

Differential Revision: https://reviews.llvm.org/D32839

llvm-svn: 303461
2017-05-19 22:37:09 +00:00
Amaury Sechet 77cfb4a85f [DAGCombine] (addcarry 0, 0, X) -> (ext/trunc X)
Summary:
While this makes some case better and some case worse - so it's unclear if it is a worthy combine just by itself - this is a useful canonicalisation.

As per discussion in D32756 .

Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32916

llvm-svn: 303441
2017-05-19 18:20:44 +00:00
Craig Topper 8a950275f7 [Statistics] Add a method to atomically update a statistic that contains a maximum
Summary:
There are several places in the codebase that try to calculate a maximum value in a Statistic object. We currently do this in one of two ways:

  MaxNumFoo = std::max(MaxNumFoo, NumFoo);

or

  MaxNumFoo = (MaxNumFoo > NumFoo) ? MaxNumFoo : NumFoo;

The first version reads from MaxNumFoo one time and uncontionally rwrites to it. The second version possibly reads it twice depending on the result of the first compare.  But we have no way of knowing if the value was changed by another thread between the reads and the writes.

This patch adds a method to the Statistic object that can ensure that we only store if our value is the max and the previous max didn't change after we read it. If it changed we'll recheck if our value should still be the max or not and try again.

This spawned from an audit I'm trying to do of all places we uses the implicit conversion to unsigned on the Statistics objects. See my previous thread on llvm-dev https://groups.google.com/forum/#!topic/llvm-dev/yfvxiorKrDQ

Reviewers: dberlin, chandlerc, hfinkel, dblaikie

Reviewed By: chandlerc

Subscribers: llvm-commits, sanjoy

Differential Revision: https://reviews.llvm.org/D33301

llvm-svn: 303318
2017-05-18 00:51:39 +00:00
Nirav Dave da8f221273 Elide stores which are overwritten without being observed.
Summary:
In SelectionDAG, when a store is immediately chained to another store
to the same address, elide the first store as it has no observable
effects. This is causes small improvements dealing with intrinsics
lowered to stores.

Test notes:

* Many testcases overwrite store addresses multiple times and needed
  minor changes, mainly making stores volatile to prevent the
  optimization from optimizing the test away.

* Many X86 test cases optimized out instructions associated with
  associated with va_start.

* Note that test_splat in CodeGen/AArch64/misched-stp.ll no longer has
  dependencies to check and can probably be removed and potentially
  replaced with another test.

Reviewers: rnk, john.brawn

Subscribers: aemerson, rengolin, qcolombet, jyknight, nemanjai, nhaehnle, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D33206

llvm-svn: 303198
2017-05-16 19:43:56 +00:00
Nirav Dave cfd357a61a [DAG] Prune deleted nodes in TokenFactor
Fix visitTokenFactor to correctly remove deleted nodes. NFC.

llvm-svn: 303181
2017-05-16 15:49:02 +00:00
Peter Collingbourne 6f0ecca3b5 IR: Give function GlobalValue::getRealLinkageName() a less misleading name: dropLLVMManglingEscape().
This function gives the wrong answer on some non-ELF platforms in some
cases. The function that does the right thing lives in Mangler.h. To try to
discourage people from using this function, give it a different name.

Differential Revision: https://reviews.llvm.org/D33162

llvm-svn: 303134
2017-05-16 00:39:01 +00:00
Simon Pilgrim 754c1618ec [SelectionDAG] Added support for EXTRACT_SUBVECTOR/CONCAT_VECTORS demandedelts in ComputeNumSignBits
llvm-svn: 302997
2017-05-13 22:10:58 +00:00
Simon Pilgrim 7666afd042 [SelectionDAG] Add VECTOR_SHUFFLE support to ComputeNumSignBits
llvm-svn: 302993
2017-05-13 19:57:10 +00:00
Craig Topper 9fe357971c [ValueTracking] Remove const_casts on several calls to computeKnownBits and ComputeSignBit. NFC
llvm-svn: 302991
2017-05-13 17:22:16 +00:00
Tim Shen 10c64e6aea [PPC] Move the combine "a << (b % (sizeof(a) * 8)) -> (PPCshl a, b)" to the backend. NFC.
Summary:
Eli pointed out that it's unsafe to combine the shifts to ISD::SHL etc.,
because those are not defined for b > sizeof(a) * 8, even after some of
the combiners run.

However, PPCISD::SHL defines that behavior (as the instructions themselves).
Move the combination to the backend.

The tests in shift_mask.ll still pass.

Reviewers: echristo, hfinkel, efriedma, iteratee

Subscribers: nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D33076

llvm-svn: 302937
2017-05-12 19:25:37 +00:00
Craig Topper 8df66c602a [KnownBits] Add bit counting methods to KnownBits struct and use them where possible
This patch adds min/max population count, leading/trailing zero/one bit counting methods.

The min methods return answers based on bits that are known without considering unknown bits. The max methods give answers taking into account the largest count that unknown bits could give.

Differential Revision: https://reviews.llvm.org/D32931

llvm-svn: 302925
2017-05-12 17:20:30 +00:00
Simon Pilgrim eabf6fc4b5 [DAGCombine] Use SelectionDAG::getAnyExtOrTrunc helper. NFCI.
llvm-svn: 302907
2017-05-12 15:26:50 +00:00
Simon Pilgrim f01c301f72 [DAGCombine] Use SelectionDAG::getZExtOrTrunc helper. NFCI.
llvm-svn: 302897
2017-05-12 13:22:12 +00:00
Simon Pilgrim a6ed1b2f12 Use SDValue::getOperand() helper. NFCI.
llvm-svn: 302896
2017-05-12 13:20:24 +00:00
Vadzim Dambrouski 38e30197c3 [MSP430] Generate EABI-compliant libcalls
Updates the MSP430 target to generate EABI-compatible libcall names.
As a byproduct, adjusts the hardware multiplier options available in
the MSP430 target, adds support for promotion of the ISD::MUL operation
for 8-bit integers, and correctly marks R11 as used by call instructions.

Patch by Andrew Wygle.

Differential Revision: https://reviews.llvm.org/D32676

llvm-svn: 302820
2017-05-11 19:56:14 +00:00
Simon Pilgrim 6faddcbd07 [DAGCombine] Use SelectionDAG::getAnyExtOrTrunc helper. NFCI.
llvm-svn: 302808
2017-05-11 16:40:44 +00:00
Simon Pilgrim a4a13a0da0 Strip trailing whitespace. NFCI.
llvm-svn: 302784
2017-05-11 10:03:05 +00:00
David L. Jones bbd97d273b Revert "[SDAG] Relax conditions under stores of loaded values can be merged"
This reverts r302712.

The change fails with ASAN enabled:

ERROR: AddressSanitizer: use-after-poison on address ... at ...
READ of size 2 at ... thread T0
  #0 ... in llvm::SDNode::getNumValues() const <snip>/include/llvm/CodeGen/SelectionDAGNodes.h:855:42
  #1 ... in llvm::SDNode::hasAnyUseOfValue(unsigned int) const <snip>/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:7270:3
  #2 ... in llvm::SDValue::use_empty() const <snip> include/llvm/CodeGen/SelectionDAGNodes.h:1042:17
  #3 ... in (anonymous namespace)::DAGCombiner::MergeConsecutiveStores(llvm::StoreSDNode*) <snip>/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:12944:7

Reviewers: niravd

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D33081

llvm-svn: 302746
2017-05-10 23:56:21 +00:00