Commit Graph

2148 Commits

Author SHA1 Message Date
Simon Pilgrim d857f64c31 [SelectionDAG] CreateTopologicalOrder - don't use iterator
We shouldn't use an iterator to loop across a std::vector when the same loop is adding elements to that std::vector

Found by cppcheck

llvm-svn: 359900
2019-05-03 15:50:37 +00:00
Simon Pilgrim 42d2b604b5 [SelectionDAG] Use INT_MIN as (1 << 31) is UB for signed integers. NFCI.
llvm-svn: 359873
2019-05-03 11:32:00 +00:00
Simon Pilgrim bfd00a6440 [SelectionDAG] computeKnownBits - remove some duplicate/shadow variables. NFCI.
llvm-svn: 359872
2019-05-03 11:11:03 +00:00
Craig Topper e8a1cde886 [SelectionDAG] Add asserts to verify the vectorness of input and output types of TRUNCATE/ZERO_EXTEND/ANY_EXTEND/SIGN_EXTEND agree
As a result of the underlying cause of PR41678 we created an ANY_EXTEND node with a scalar result type and v1i1 input type. Ideally we would have asserted for this instead of letting it go through to instruction selection and generate bad machine IR

Differential Revision: https://reviews.llvm.org/D61463

llvm-svn: 359836
2019-05-02 22:26:26 +00:00
Sanjay Patel 284472be6d [SelectionDAG] remove constant folding limitations based on FP exceptions
We don't have FP exception limits in the IR constant folder for the binops (apart from strict ops),
so it does not make sense to have them here in the DAG either. Nothing else in the backend tries
to preserve exceptions (again outside of strict ops), so I don't see how this could have ever
worked for real code that cares about FP exceptions.

There are still cases (examples: unary opcodes in SDAG, FMA in IR) where we are trying (at least
partially) to preserve exceptions without even asking if the target supports FP exceptions. Those
should be corrected in subsequent patches.

Real support for FP exceptions requires several changes to handle the constrained/strict FP ops.

Differential Revision: https://reviews.llvm.org/D61331

llvm-svn: 359791
2019-05-02 14:47:59 +00:00
Tim Northover ee2474df9f DAG: allow DAG pointer size different from memory representation.
In preparation for supporting ILP32 on AArch64, this modifies the SelectionDAG
builder code so that pointers are allowed to have a larger type when "live" in
the DAG compared to memory.

Pointers get zero-extended whenever they are loaded, and truncated prior to
stores.  In addition, a few not quite so obvious locations need updating:

  * A GEP that has not been marked inbounds needs to enforce the IR-documented
    2s-complement wrapping at the memory pointer size. Inbounds GEPs are
    undefined if they overflow the address space, so no additional operations
    are needed.
  * Signed comparisons would give incorrect results if performed on the
    zero-extended values.

This shouldn't affect CodeGen for now, but will become active when the AArch64
ILP32 support is committed.

llvm-svn: 359676
2019-05-01 12:37:30 +00:00
Sanjay Patel 0387bf5269 [SelectionDAG] remove div-by-zero constant folding restriction
We don't have this restriction in IR, so it should not be here
either simply out of consistency. Code that wants to handle FP
exceptions is expected to use the 'strict' variants of these
nodes.

We don't get the frem case because frem by 0.0 produces NaN (invalid),
and that's the remaining check here (so the removed check for frem
was dead code AFAIK).

This is the only place in SDAG that uses "HasFPExceptions", so I
think we should remove that entirely as a follow-up patch.

llvm-svn: 359566
2019-04-30 14:37:15 +00:00
Sjoerd Meijer 0ed4619679 [TargetLowering] findOptimalMemOpLowering. NFCI.
This was a local static funtion in SelectionDAG, which I've promoted to
TargetLowering so that I can reuse it to estimate the cost of a memory
operation in D59787.

Differential Revision: https://reviews.llvm.org/D59766

llvm-svn: 359543
2019-04-30 10:09:15 +00:00
Sjoerd Meijer 180f1ae57c [TargetLowering] Change getOptimalMemOpType to take a function attribute list
The MachineFunction wasn't used in getOptimalMemOpType, but more importantly,
this allows reuse of findOptimalMemOpLowering that is calling getOptimalMemOpType.

This is the groundwork for the changes in D59766 and D59787, that allows
implementation of TTI::getMemcpyCost.

Differential Revision: https://reviews.llvm.org/D59785

llvm-svn: 359537
2019-04-30 08:38:12 +00:00
Sanjay Patel bf8aacb715 [SelectionDAG] move splat util functions up from x86 lowering
This was supposed to be NFC, but the change in SDLoc
definitions causes instruction scheduling changes.

There's nothing x86-specific in this code, and it can
likely be used from DAGCombiner's simplifyVBinOp().

llvm-svn: 358930
2019-04-22 22:43:36 +00:00
Sanjay Patel e197c617a6 [SelectionDAG] soften splat mask assert/unreachable (PR41535)
These are general queries, so they should not die when given
a degenerate input like an all undef mask. Callers should be
able to deal with an op that will eventually be simplified away.

llvm-svn: 358761
2019-04-19 15:31:11 +00:00
Tim Northover 9db00f7e5b DAG: propagate whether an arg is a pointer for CallingConv decisions.
The arm64_32 ABI specifies that pointers (despite being 32-bits) should be
zero-extended to 64-bits when passed in registers for efficiency reasons. This
means that the SelectionDAG needs to be able to tell the backend that an
argument was originally a pointer, which is implmented here.

Additionally, some memory intrinsics need to be declared as taking an i8*
instead of an iPTR.

There should be no CodeGen change yet, but it will be triggered when AArch64
backend support for ILP32 is added.

llvm-svn: 358398
2019-04-15 12:03:54 +00:00
Bjorn Pettersson 60569363a5 [SelectionDAG] Use KnownBits::computeForAddSub/computeForAddCarry
Summary:
Use KnownBits::computeForAddSub/computeForAddCarry
in SelectionDAG::computeKnownBits when doing value
tracking for addition/subtraction.

This should improve the precision of the known bits,
as we only used to make a simple estimate of known
zeroes. The KnownBits support functions are also
able to deduce bits that are known to be one in the
result.

Reviewers: spatel, RKSimon, nikic, lebedev.ri

Reviewed By: nikic

Subscribers: nikic, javed.absar, lebedev.ri, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D60460

llvm-svn: 358372
2019-04-15 07:19:11 +00:00
David Green 0861c87b06 Revert rL357745: [SelectionDAG] Compute known bits of CopyFromReg
Certain optimisations from ConstantHoisting and CGP rely on Selection DAG not
seeing through to the constant in other blocks. Revert this patch while we come
up with a better way to handle that.

I will try to follow this up with some better tests.

llvm-svn: 358113
2019-04-10 18:00:41 +00:00
Simon Pilgrim 17586cda4a [SelectionDAG] Add fcmp UNDEF handling to SelectionDAG::FoldSetCC
Second half of PR40800, this patch adds DAG undef handling to fcmp instructions to match the behavior in llvm::ConstantFoldCompareInstruction, this permits constant folding of vector comparisons where some elements had been reduced to UNDEF (by SimplifyDemandedVectorElts etc.).

This involves a lot of tweaking to reduced tests as bugpoint loves to reduce fcmp arguments to undef........

Differential Revision: https://reviews.llvm.org/D60006

llvm-svn: 357765
2019-04-05 14:56:21 +00:00
Piotr Sobczak 0376ac1d94 [SelectionDAG] Compute known bits of CopyFromReg
Summary:
Teach SelectionDAG how to compute known bits of ISD::CopyFromReg if
the virtual reg used has one def only.

This can be particularly useful when calling isBaseWithConstantOffset()
with the ISD::CopyFromReg argument, as more optimizations may get enabled
in the result.

Also add a missing truncation on X86, found by testing of this patch.

Change-Id: Id1c9fceec862d118c54a5b53adf72ada5d6daefa

Reviewers: bogner, craig.topper, RKSimon

Reviewed By: RKSimon

Subscribers: lebedev.ri, nemanjai, jvesely, nhaehnle, javed.absar, jsji, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59535

llvm-svn: 357745
2019-04-05 07:44:09 +00:00
Evandro Menezes 85bd3978ae [IR] Refactor attribute methods in Function class (NFC)
Rename the functions that query the optimization kind attributes.

Differential revision: https://reviews.llvm.org/D60287

llvm-svn: 357731
2019-04-04 22:40:06 +00:00
Nirav Dave 610036c506 [DAG] Set up infrastructure to avoid smart constructor-based dangling nodes
Summary:
Various SelectionDAG non-combine operations (e.g. the getNode smart
constructor and legalization) may leave dangling nodes by applying
optimizations without fully pruning unused result values. This results
in nodes that are never added to the worklist and therefore can not be
pruned.

Add a node inserter for the combiner to make sure such nodes have the
chance of being pruned. This allows a number of additional peephole
optimizations.

Reviewers: efriedma, RKSimon, craig.topper, jyknight

Reviewed By: jyknight

Subscribers: msearles, jyknight, sdardis, nemanjai, javed.absar, hiraditya, jrtc27, atanasyan, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58068

llvm-svn: 357279
2019-03-29 17:26:40 +00:00
Nirav Dave 8b9c9822a1 [DAG] Fix Lifetime Node ID hashing.
llvm-svn: 357179
2019-03-28 15:53:01 +00:00
Nirav Dave c6dfaa0e83 Revert r356996 "[DAG] Avoid smart constructor-based dangling nodes."
This patch appears to trigger very large compile time increases in
halide builds.

llvm-svn: 357116
2019-03-27 19:54:41 +00:00
Sanjay Patel bb5cba3cca [SDAG] add simplifications for FP at node creation time
We have the folds for fadd/fsub/fmul already in DAGCombiner,
so it may be possible to remove that code if we can guarantee that
these ops are zapped before they can exist.

llvm-svn: 357029
2019-03-26 20:54:15 +00:00
Nirav Dave a28c514581 [DAG] Avoid smart constructor-based dangling nodes.
Various SelectionDAG non-combine operations (e.g. the getNode smart
constructor and legalization) may leave dangling nodes by applying
optimizations or not fully pruning unused result values. This can
result in nodes that are never added to the worklist and therefore can
not be pruned.

Add a node inserter as the current node deleter to make sure such
nodes have the chance of being pruned.

Many minor changes, mostly positive.

llvm-svn: 356996
2019-03-26 15:08:14 +00:00
Simon Pilgrim 167af1bafb [SelectionDAG] Add icmp UNDEF handling to SelectionDAG::FoldSetCC
First half of PR40800, this patch adds DAG undef handling to icmp instructions to match the behaviour in llvm::ConstantFoldCompareInstruction and SimplifyICmpInst, this permits constant folding of vector comparisons where some elements had been reduced to UNDEF (by SimplifyDemandedVectorElts etc.).

This involved a lot of tweaking to reduced tests as bugpoint loves to reduce icmp arguments to undef........

Differential Revision: https://reviews.llvm.org/D59363

llvm-svn: 356938
2019-03-25 18:51:57 +00:00
Tim Renouf c302b9b5fe [CodeGen] Prepare for introduction of v3 and v5 MVTs
AMDGPU would like to have MVTs for v3i32, v3f32, v5i32, v5f32. This
commit does not add them, but makes preparatory changes:

* Exclude non-legal non-power-of-2 vector types from ComputeRegisterProp
  mechanism in TargetLoweringBase::getTypeConversion.

* Cope with SETCC and VSELECT for odd-width i1 vector when the other
  vectors are legal type.

Some of this patch is from Matt Arsenault, also of AMD.

Differential Revision: https://reviews.llvm.org/D58899

Change-Id: Ib5f23377dbef511be3a936211a0b9f94e46331f8
llvm-svn: 356350
2019-03-17 21:43:12 +00:00
Simon Pilgrim 360ce82db2 [DAG] Move integer setcc %x, %x folding into FoldSetCC
First step towards PR40800 - I intend to move the float case in a separate future patch.

I had to tweak the (overly reduced) thumb2 test and the x86 widening test change is annoying (no longer rematerializable) but we should address this separately.

Differential Revision: https://reviews.llvm.org/D59244

llvm-svn: 356040
2019-03-13 11:08:57 +00:00
Simon Pilgrim f3be93a2ff [DAG] FoldSetCC - reuse valuetype + ensure its simple.
llvm-svn: 355847
2019-03-11 17:56:18 +00:00
Simon Pilgrim 1bb5b56485 [DAG] Move SetCC NaN handling into FoldSetCC
llvm-svn: 355845
2019-03-11 17:43:10 +00:00
Sanjay Patel 8b72080d4d [SDAG] move FP constant folding to helper function; NFC
llvm-svn: 355411
2019-03-05 16:42:33 +00:00
Simon Pilgrim 37a63a748e Use SDValue::getConstantOperandAPInt helper where possible. NFCI.
llvm-svn: 355267
2019-03-02 11:11:22 +00:00
Bjorn Pettersson d30f308a9f Add support for computing "zext of value" in KnownBits. NFCI
Summary:
The description of KnownBits::zext() and
KnownBits::zextOrTrunc() has confusingly been telling
that the operation is equivalent to zero extending the
value we're tracking. That has not been true, instead
the user has been forced to explicitly set the extended
bits as known zero afterwards.

This patch adds a second argument to KnownBits::zext()
and KnownBits::zextOrTrunc() to control if the extended
bits should be considered as known zero or as unknown.

Reviewers: craig.topper, RKSimon

Reviewed By: RKSimon

Subscribers: javed.absar, hiraditya, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58650

llvm-svn: 355099
2019-02-28 15:45:29 +00:00
Simon Pilgrim 80d0e9c563 [SelectionDAG] Add demanded elts variants to isConstOrConstSplat helpers. NFCI.
These helpers extend the existing isConstOrConstSplat helper checks to support DemandedElts masks as well.

We already had a local version of this in SelectionDAG that computeKnownBits/ComputeNumSignBits made use of, but this adds the functionality directly to the BuildVectorSDNode node and extends isConstOrConstSplat etc. to use that.

This will allow us to reuse the functionality in SimplifyDemandedVectorElts/SimplifyDemandedBits.

Differential Revision: https://reviews.llvm.org/D58503

llvm-svn: 354797
2019-02-25 16:31:58 +00:00
Craig Topper be3348573e [LegalizeTypes][AArch64][X86] Make type legalization of vector (S/U)ADD/SUB/MULO follow getSetCCResultType for the overflow bits. Make UnrollVectorOverflowOp properly convert from scalar boolean contents to vector boolean contents
Summary:
When promoting the over flow vector for these ops we should use the target's desired setcc result type. This way a v8i32 result type will use a v8i32 overflow vector instead of a v8i16 overflow vector. A v8i16 overflow vector will cause LegalizeDAG/LegalizeVectorOps to have to use v8i32 and truncate to v8i16 in its expansion. By doing this in type legalization instead, we get the truncate into the DAG earlier and give DAG combine more of a chance to optimize it.

We also have to fix unrolling to use the scalar setcc result type for the scalarized operation, and convert it to the required vector element type after the scalar operation. We have to observe the vector boolean contents when doing this conversion. The previous code was just taking the scalar result and putting it in the vector. But for X86 and AArch64 that would have only put a the boolean value in bit 0 of the element and left all other bits in the element 0. We need to ensure all bits in the element are the same. I'm using a select with constants here because that's what setcc unrolling in LegalizeVectorOps used.

Reviewers: spatel, RKSimon, nikic

Reviewed By: nikic

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

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58567

llvm-svn: 354753
2019-02-24 19:23:36 +00:00
Matt Arsenault 0280a5e143 DAG: Add helper for creating shifts with correct type
llvm-svn: 354649
2019-02-22 03:38:47 +00:00
Clement Courbet a0321c23e8 Re-land part of r354244 "[DAGCombiner] Eliminate dead stores to stack."
This part introduces the lifetime node.

llvm-svn: 354578
2019-02-21 12:59:36 +00:00
Craig Topper 8d9c224a8c [SelectionDAG] Teach GetDemandedBits to look at the known zeros of the LHS when handling ISD::AND
If the LHS has known zeros, then the RHS immediate mask might have been simplified to remove those bits.

This patch adds a call to computeKnownBits to get the known zeroes to handle that possibility. I left an early out to skip the call if all of the demanded bits are set in the mask.

Differential Revision: https://reviews.llvm.org/D58464

llvm-svn: 354514
2019-02-20 20:52:26 +00:00
Nikita Popov c3b496de7a [SDAG] Support vector UMULO/SMULO
Second part of https://bugs.llvm.org/show_bug.cgi?id=40442.

This adds an extra UnrollVectorOverflowOp() method to SDAG, because
the general UnrollOverflowOp() method can't deal with multiple results.

Additionally we need to expand UMULO/SMULO during vector op
legalization, as it may result in unrolling, which may need additional
type legalization.

Differential Revision: https://reviews.llvm.org/D57997

llvm-svn: 354513
2019-02-20 20:41:44 +00:00
Craig Topper f4923db5a3 Revert r354498 "[X86] Add test case to show missed opportunity to remove an explicit AND on the bit position from BT when it has known zeros."
I accidentally committed more than just the test.

llvm-svn: 354499
2019-02-20 18:47:26 +00:00
Craig Topper f8498a615b [X86] Add test case to show missed opportunity to remove an explicit AND on the bit position from BT when it has known zeros.
If the bit position has known zeros in it, then the AND immediate will likely be optimized to remove bits.

This can prevent GetDemandedBits from recognizing that the AND is unnecessary.

llvm-svn: 354498
2019-02-20 18:45:38 +00:00
Clement Courbet 292291fb90 Revert r354244 "[DAGCombiner] Eliminate dead stores to stack."
Breaks some bots.

llvm-svn: 354245
2019-02-18 08:24:29 +00:00
Clement Courbet 57f34dbd3e [DAGCombiner] Eliminate dead stores to stack.
Summary:
A store to an object whose lifetime is about to end can be removed.

See PR40550 for motivation.

Reviewers: niravd

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D57541

llvm-svn: 354244
2019-02-18 07:59:01 +00:00
Philip Reames e4cfb7dae8 [SelectionDAG] Inline a single use helper function, and remove last non-MMO interface [NFC]
For D57601, we need to know whether the instruction is volatile.  We'd either have to pass yet another parameter, or just standardize on the MMO interface.  I chose the second.

llvm-svn: 353989
2019-02-13 23:01:11 +00:00
Philip Reames 41f400c948 [SelectionDAG] Kill last uses of getAtomic w/o a MMO operand [NFC]
The helper function was used by only two callers, and largely ended up providing distinct functionality based on optional arguments and opcode.  Inline and simply to make the functionality much more clear.

llvm-svn: 353977
2019-02-13 20:42:59 +00:00
Simon Pilgrim c5744d4d69 [DAG] Add optional AllowUndefs to isNullOrNullSplat
No change in default behaviour (AllowUndefs = false)

llvm-svn: 353646
2019-02-10 17:42:15 +00:00
Sanjay Patel 6502b1444d [SDAG] improve variable names; NFC
The version of FoldConstantArithmetic() that takes arbitrary nodes
was confusingly naming those nodes as constants when they might
not be; also "Cst" reads like "Cast".

llvm-svn: 352884
2019-02-01 16:06:53 +00:00
Matt Arsenault a5840c3c39 Codegen support for atomicrmw fadd/fsub
llvm-svn: 351851
2019-01-22 18:36:06 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Florian Hahn d2c733b429 [SelectionDAG] Add getTokenFactor, which splits nodes with > 64k operands.
This functionality is required at multiple places which potentially
create large operand lists, like SelectionDAGBuilder or DAGCombiner.

Differential Revision: https://reviews.llvm.org/D56739

llvm-svn: 351552
2019-01-18 14:05:59 +00:00
Florian Hahn 1b81772328 [SelectionDAG] Add static getMaxNumOperands function to SDNode.
Summary:
Use this helper to make sure we use the same value at various places.
This will likely be needed at more places were we currently crash
because we use more operands than possible.

Also makes it easier to change in the future.

Reviewers: RKSimon, craig.topper, efriedma, aemerson

Reviewed By: RKSimon

Subscribers: hiraditya, arsenm, llvm-commits

Differential Revision: https://reviews.llvm.org/D56859

llvm-svn: 351537
2019-01-18 10:00:38 +00:00
Florian Hahn e94470f1cc [SelectionDAG] Update check in createOperands to reflect max() is a valid value.
The value returned by max() is the last valid value, adjust the
comparison accordingly.

The code added in D55073 creates TokenFactors with max() operands.

Reviewers: aemerson, efriedma, RKSimon, craig.topper

Reviewed By: aemerson

Differential Revision: https://reviews.llvm.org/D56738

llvm-svn: 351318
2019-01-16 10:06:04 +00:00
Simon Pilgrim fa1f518748 [DAGCombiner] Enable sub saturation constant folding
llvm-svn: 351072
2019-01-14 15:28:53 +00:00
Simon Pilgrim 7fc6882374 [DAGCombiner] Add add/sub saturation undef handling
Match ConstantFolding.cpp:
(add_sat x, undef) -> -1
(sub_sat x, undef) -> 0

llvm-svn: 351070
2019-01-14 14:16:24 +00:00
Simon Pilgrim cfa5f06dde [DAGCombiner] Enable add saturation constant folding
llvm-svn: 351060
2019-01-14 12:34:31 +00:00
Simon Pilgrim 3d42815cd8 [SelectionDAG] Add type sanity assertions for add/sub saturation node creation.
llvm-svn: 351055
2019-01-14 11:56:59 +00:00
Craig Topper cfeb1cf9af [X86] Add INSERT_SUBVECTOR to ComputeNumSignBits
This adds support for calculating sign bits of insert_subvector. I based it on the computeKnownBits.

My motivating case is propagating sign bits information across basic blocks on AVX targets where concatenating using insert_subvector is common.

Differential Revision: https://reviews.llvm.org/D56283

llvm-svn: 350432
2019-01-04 20:50:59 +00:00
Craig Topper ed3ffae4a4 [SelectionDAG] Add SIGN_EXTEND_VECTOR_INREG support to computeKnownBits.
Differential Revision: https://reviews.llvm.org/D56168

llvm-svn: 350179
2018-12-31 19:09:30 +00:00
Richard Trieu a87b70d1db Add vtable anchor to classes.
llvm-svn: 350142
2018-12-29 02:02:13 +00:00
Justin Lebar 49fac56ea3 [NVPTX] Allow libcalls that are defined in the current module.
The patch adds a possibility to make library calls on NVPTX.

An important thing about library functions - they must be defined within
the current module. This basically should guarantee that we produce a
valid PTX assembly (without calls to not defined functions). The one who
wants to use the libcalls is probably will have to link against
compiler-rt or any other implementation.

Currently, it's completely impossible to make library calls because of
error LLVM ERROR: Cannot select: i32 = ExternalSymbol '...'. But we can
lower ExternalSymbol to TargetExternalSymbol and verify if the function
definition is available.

Also, there was an issue with a DAG during legalisation. When we expand
instruction into libcall, the inner call-chain isn't being "integrated"
into outer chain. Since the last "data-flow" (call retval load) node is
located in call-chain earlier than CALLSEQ_END node, the latter becomes
a leaf and therefore a dead node (and is being removed quite fast).
Proposed here solution relies on another data-flow pseudo nodes
(ProxyReg) which purpose is only to keep CALLSEQ_END at legalisation and
instruction selection phases - we remove the pseudo instructions before
register scheduling phase.

Patch by Denys Zariaiev!

Differential Revision: https://reviews.llvm.org/D34708

llvm-svn: 350069
2018-12-26 19:12:31 +00:00
Craig Topper 0229da8f07 [X86] Use GetDemandedBits to simplify the operands of PMULDQ/PMULUDQ.
This is an alternative to what I attempted in D56057.

GetDemandedBits is a special version of SimplifyDemandedBits that allows simplifications even when the operand has other uses. GetDemandedBits will only do simplifications that allow a node to be bypassed. It won't create new nodes or alter any of the other users.

I had to add support for bypassing SIGN_EXTEND_INREG to GetDemandedBits.

Based on a patch that Simon Pilgrim sent me in email.

Fixes PR40142.

llvm-svn: 350059
2018-12-24 19:40:20 +00:00
Simon Pilgrim 911dce2f30 [SelectionDAG] Always use the version of computeKnownBits that returns a value. NFCI.
Continues the work started by @bogner in rL340594 to remove uses of the KnownBits output paramater version.

llvm-svn: 349907
2018-12-21 14:56:18 +00:00
Simon Pilgrim 47ff0431e9 [SelectionDAG] Optional handling of UNDEF elements in matchBinaryPredicate (part 1 of 2)
Now that SimplifyDemandedBits/SimplifyDemandedVectorElts is simplifying vector elements, we're seeing more constant BUILD_VECTOR containing undefs.

This patch provides opt-in support for UNDEF elements in matchBinaryPredicate, passing NULL instead of the result ConstantSDNode* argument.

Differential Revision: https://reviews.llvm.org/D55822

llvm-svn: 349628
2018-12-19 14:09:09 +00:00
Simon Pilgrim 2072b5afbe [SelectionDAG] Optional handling of UNDEF elements in matchUnaryPredicate
Now that SimplifyDemandedBits/SimplifyDemandedVectorElts are simplifying vector elements, we're seeing more constant BUILD_VECTOR containing UNDEFs.

This patch provides opt-in handling of UNDEF elements in matchUnaryPredicate, passing NULL instead of the ConstantSDNode* argument.

I've updated SelectionDAG::simplifyShift to demonstrate its use.

Differential Revision: https://reviews.llvm.org/D55819

llvm-svn: 349616
2018-12-19 10:41:06 +00:00
Craig Topper 15b7246935 [SelectionDAG] Fix noop detection for vectors in AssertZext/AssertSext in getNode
The assertion type is always supposed to be a scalar type. So if the result VT of the assertion is a vector, we need to get the scalar VT before we can compare them.

Similarly for the assert above it.

I don't have a test case because I don't know of any place we violate this today. A coworker found this while trying to use r347287 on the 6.0 branch without also having r336868

llvm-svn: 349390
2018-12-17 20:29:13 +00:00
Simon Pilgrim 0ef977b83d [SelectionDAG] Add FSHL/FSHR support to computeKnownBits
Also exposes an issue in DAGCombiner::visitFunnelShift where we were assuming the shift amount had the result type (after legalization it'll have the targets shift amount type).

llvm-svn: 349298
2018-12-16 13:33:37 +00:00
Clement Courbet 76f4ae1092 [CodeGen] Allow mempcy/memset to generate small overlapping stores.
Summary:
All targets either just return false here or properly model `Fast`, so I
don't think there is any reason to prevent CodeGen from doing the right
thing here.

Subscribers: nemanjai, javed.absar, eraman, jsji, llvm-commits

Differential Revision: https://reviews.llvm.org/D55365

llvm-svn: 349016
2018-12-13 09:56:19 +00:00
Simon Pilgrim eb508f8ccb [SelectionDAG] Add a generic isSplatValue function
This patch introduces a generic function to determine whether a given vector type is known to be a splat value for the specified demanded elements, recursing up the DAG looking for BUILD_VECTOR or VECTOR_SHUFFLE splat patterns.

It also keeps track of the elements that are known to be UNDEF - it returns true if all the demanded elements are UNDEF (as this may be useful under some circumstances), so this needs to be handled by the caller.

A wrapper variant is also provided that doesn't take the DemandedElts or UndefElts arguments for cases where we just want to know if the SDValue is a splat or not (with/without UNDEFS).

I had hoped to completely remove the X86 local version of this function, but I'm seeing some regressions in shift/rotate codegen that will take a little longer to fix and I hope to get this in sooner so I can continue work on PR38243 which needs more capable splat detection.

Differential Revision: https://reviews.llvm.org/D55426

llvm-svn: 348953
2018-12-12 18:32:29 +00:00
Clement Courbet 8b6434bbb9 Revert r348843 "[CodeGen] Allow mempcy/memset to generate small overlapping stores."
Breaks ARM/memcpy-inline.ll

llvm-svn: 348844
2018-12-11 13:38:43 +00:00
Clement Courbet 93b3445770 [CodeGen] Allow mempcy/memset to generate small overlapping stores.
Summary:
All targets either just return false here or properly model `Fast`, so I
don't think there is any reason to prevent CodeGen from doing the right
thing here.

Subscribers: nemanjai, javed.absar, eraman, jsji, llvm-commits

Differential Revision: https://reviews.llvm.org/D55365

llvm-svn: 348843
2018-12-11 13:15:56 +00:00
Jeremy Morse 045c67769d [DebugInfo] Emit undef DBG_VALUEs when SDNodes are optimised out
This is a fix for PR39896, where dbg.value's of SDNodes that have been
optimised out do not lead to "DBG_VALUE undef" instructions being created.
Such undef instructions are necessary to terminate earlier variable
ranges, otherwise variable values leak past the point where they're valid.

The "invalidated" flag of SDDbgValue is currently being abused to mean two
things:
 * The corresponding SDNode is now invalid
 * This SDDbgValue should not be emitted
Of which there are several legitimate combinations of meaning:
 * The SDNode has been invalidated and we should emit "DBG_VALUE undef"
 * The SDNode has been invalidated but the debug data was salvaged, don't
   emit anything for this SDDbgValue
 * This SDDbgValue has been emitted

This patch introduces distinct "Emitted" and "Invalidated" fields to the
SDDbgValue class, updates users accordingly, and generates "undef"
DBG_VALUEs for invalidated records. Awkwardly, there are circumstances
where we emit SDDbgValue's twice, specifically DebugInfo/X86/dbg-addr-dse.ll
which I've preserved.

Differential Revision: https://reviews.llvm.org/D55372

llvm-svn: 348751
2018-12-10 11:20:47 +00:00
Craig Topper b4c96f5a32 [SelectionDAG] Remove ISD::ADDC/ADDE from some undef handling code in getNode. NFCI
These nodes should have two results. A real VT and a Glue. But this code would have returned Undef which would only be a single result. But we're in the single result version of getNode so these opcodes should never be seen by this function anyway.

llvm-svn: 348670
2018-12-08 00:27:34 +00:00
Simon Pilgrim d498dee7a2 [SelectionDAG] Don't pass on DemandedElts when handling SCALAR_TO_VECTOR
Fixes an assertion:

llc: lib/CodeGen/SelectionDAG/SelectionDAG.cpp:2200: llvm::KnownBits llvm::SelectionDAG::computeKnownBits(llvm::SDValue, const llvm::APInt&, unsigned int) const: Assertion `(!Op.getValueType().isVector() || NumElts == Op.getValueType().getVectorNumElements()) && "Unexpected vector size"' failed.

Committed on behalf of: @pendingchaos (Rhys Perry)

Differential Revision: https://reviews.llvm.org/D55223

llvm-svn: 348574
2018-12-07 09:18:44 +00:00
Amara Emerson 814a6794ba [SelectionDAG] Split very large token factors for loads into 64k chunks.
There's a 64k limit on the number of SDNode operands, and some very large
functions with 64k or more loads can cause crashes due to this limit being hit
when a TokenFactor with this many operands is created. To fix this, create
sub-tokenfactors if we've exceeded the limit.

No test case as it requires a very large function.

rdar://45196621

Differential Revision: https://reviews.llvm.org/D55073

llvm-svn: 348324
2018-12-05 00:41:30 +00:00
Sanjay Patel b205606d3e [SelectionDAG] fold constant with undef vector per element
This makes the SDAG behavior consistent with the way we do this in IR.
It's possible that we were getting the wrong answer before. For example,
'xor undef, undef --> 0' but 'xor undef, C' --> undef. 

But the most practical improvement is likely as shown in the tests here - 
for FP, we were overconstraining undef lanes to NaN, and that can prevent 
vector simplifications/narrowing (see D51553).

llvm-svn: 348090
2018-12-02 13:48:42 +00:00
Sanjay Patel 1901a12e76 [SelectionDAG] fold FP binops with 2 undef operands to undef
llvm-svn: 348016
2018-11-30 18:38:52 +00:00
Sanjay Patel 04435677d0 [SelectionDAG] move constant or splat functions to common location
rL347502 moved the null sibling, so we should group all of these
together. I'm not sure why these aren't methods of the SDValue
class itself, but that's another patch if that's possible.

llvm-svn: 347523
2018-11-25 16:09:32 +00:00
Sanjay Patel 7e119c0400 [DAG] consolidate shift simplifications
...and use them to avoid creating obviously undef values as
discussed in the post-commit thread for r347478.

The diffs in vector div/rem show that we were missing real
optimizations by creating bogus shift nodes.

llvm-svn: 347502
2018-11-23 20:05:12 +00:00
Stanislav Mekhanoshin 54ebfe8aee Implement computeKnownBits for scalar_to_vector
Differential Revision: https://reviews.llvm.org/D54728

llvm-svn: 347274
2018-11-19 23:34:07 +00:00
Sanjay Patel b25adf5edb [SelectionDAG] simplify vector select with undef operand(s)
llvm-svn: 347227
2018-11-19 17:06:05 +00:00
Sanjay Patel a1dca3553e [SelectionDAG] simplify select FP with undef condition
llvm-svn: 347212
2018-11-19 14:42:28 +00:00
Sanjay Patel c036d844be [SelectionDAG] add simplifySelect() to reduce code duplication; NFC
This should be extended to handle FP and vectors in follow-up patches.

llvm-svn: 347210
2018-11-19 14:35:22 +00:00
Sanjay Patel 8c0cd77bff [DAG] add undef simplifications for select nodes
Sadly, this duplicates (twice) the logic from InstSimplify. There
might be some way to at least share the DAG versions of the code, 
but copying the folds seems to be the standard method to ensure 
that we don't miss these folds. 

Unlike in IR, we don't run DAGCombiner to fixpoint, so there's no 
way to ensure that we do these kinds of simplifications unless the 
code is repeated at node creation time and during combines.

There were other tests that would become worthless with this
improvement that I changed as pre-commits:
rL347161
rL347164
rL347165
rL347166
rL347167

I'm not sure how to salvage the remaining tests (diffs in this patch).
So the x86 tests verify that the new code is working as intended.
The AMDGPU test is actually similar to my motivating case: we have
some undef value that has survived to machine IR in an x86 test, and 
then it gets folded in some weird way, or we crash if we don't transfer
the undef flag. But we would have been better off never getting to that
point by doing these simplifications.

This will lead back to PR32023 someday...
https://bugs.llvm.org/show_bug.cgi?id=32023

llvm-svn: 347170
2018-11-18 17:36:23 +00:00
Sanjay Patel 42c22a1f87 [SelectionDAG] simplify code; NFC
llvm-svn: 347160
2018-11-18 14:39:03 +00:00
Fangrui Song 7570932977 Use llvm::copy. NFC
llvm-svn: 347126
2018-11-17 01:44:25 +00:00
Craig Topper aca8390216 [SelectionDAG][X86] Relax restriction on the width of an input to *_EXTEND_VECTOR_INREG. Use them and regular *_EXTEND to replace the X86 specific VSEXT/VZEXT opcodes
Previously, the extend_vector_inreg opcode required their input register to be the same total width as their output. But this doesn't match up with how the X86 instructions are defined. For X86 the input just needs to be a legal type with at least enough elements to cover the output.

This patch weakens the check on these nodes and allows them to be used as long as they have more input elements than output elements. I haven't changed type legalization behavior so it will still create them with matching input and output sizes.

X86 will custom legalize these nodes by shrinking the input to be a 128 bit vector and once we've done that we treat them as legal operations. We still have one case during type legalization where we must custom handle v64i8 on avx512f targets without avx512bw where v64i8 isn't a legal type. In this case we will custom type legalize to a *extend_vector_inreg with a v16i8 input. After that the input is a legal type so type legalization should ignore the node and doesn't need to know about the relaxed restriction. We are no longer allowed to use the default expansion for these nodes during vector op legalization since the default expansion uses a shuffle which required the widths to match. Custom legalization for all types will prevent us from reaching the default expansion code.

I believe DAG combine works correctly with the released restriction because it doesn't check the number of input elements.

The rest of the patch is changing X86 to use either the vector_inreg nodes or the regular zero_extend/sign_extend nodes. I had to add additional isel patterns to handle any_extend during isel since simplifydemandedbits can create them at any time so we can't legalize to zero_extend before isel. We don't yet create any_extend_vector_inreg in simplifydemandedbits.

Differential Revision: https://reviews.llvm.org/D54346

llvm-svn: 346784
2018-11-13 19:45:21 +00:00
Craig Topper f2e65f8636 [SelectionDAG] Fix a -Wparentheses warning from gcc in an assert. NFC
gcc wants parentheses around the logical OR since there is a logical AND for the string.

llvm-svn: 346564
2018-11-09 23:11:30 +00:00
Craig Topper 8cca8bd4aa [SelectionDAG] Assert on the width of DemandedElts argument to computeKnownBits for all vector typed operations not just build_vector.
Fix AArch64 unit test that fails with the assertion added.

llvm-svn: 346437
2018-11-08 20:29:17 +00:00
Cameron McInally 9757d5d6c1 [FPEnv] Add constrained CEIL/FLOOR/ROUND/TRUNC intrinsics
Differential Revision: https://reviews.llvm.org/D53411

llvm-svn: 346141
2018-11-05 15:59:49 +00:00
Craig Topper 1ba86188cf [SelectionDAG] Remove special methods for creating *_EXTEND_VECTOR_INREG nodes. Move asserts into getNode.
These methods were just wrappers around getNode with additional asserts (identical and repeated 3 times). But getNode already has a switch that can be used to hold these asserts that allows them to be shared for all 3 opcodes. This also enables checking on the places that create these nodes without using the wrappers.

The rest of the patch is just changing all callers to use getNode directly.

llvm-svn: 346087
2018-11-04 02:10:18 +00:00
Cameron McInally 2ad870e785 [FPEnv] [FPEnv] Add constrained intrinsics for MAXNUM and MINNUM
Differential Revision: https://reviews.llvm.org/D53216

llvm-svn: 345650
2018-10-30 21:01:29 +00:00
Sanjay Patel 680c9227ca [SelectionDAG] fix build warning for mismatched signs in compare; NFC
llvm-svn: 345598
2018-10-30 13:47:19 +00:00
Simon Pilgrim 858303b827 [SelectionDAG] Add FoldBUILD_VECTOR to simplify new BUILD_VECTOR nodes
Similar to FoldCONCAT_VECTORS, this patch adds FoldBUILD_VECTOR to simplify cases that can avoid the creation of the BUILD_VECTOR - if all the operands are UNDEF or if the BUILD_VECTOR simplifies to a copy.

This exposed an assumption in some AMDGPU code that getBuildVector was guaranteed to be a BUILD_VECTOR node that I've tried to handle.	
	
Differential Revision: https://reviews.llvm.org/D53760

llvm-svn: 345578
2018-10-30 10:32:11 +00:00
Craig Topper 7a18b4bc51 [SelectionDAG] Fix bad indentation. NFC
llvm-svn: 345481
2018-10-28 21:24:20 +00:00
Craig Topper 7bf85f5c8d [LegalizeTypes] Stop DAGTypeLegalizer::getSETCCWidenedResultTy from creating illegal setccs. Add checks for valid setccs
The DAGTypeLegalizer::getSETCCWidenedResultTy was widening the MaskVT, but the code in convertMask called after getSETCCWidenedResultTy had no idea this widening had occurred. So none of the operands were widened when convertMask created new setccs with the widened VT.

This patch removes the widening and adds some asserts to getNode to validate the types of setccs to prevent issues like this in the future.

Differential Revision: https://reviews.llvm.org/D53743

llvm-svn: 345428
2018-10-26 20:59:55 +00:00
Thomas Lively 30f1d69115 [NFC] Rename minnan and maxnan to minimum and maximum
Summary:
Changes all uses of minnan/maxnan to minimum/maximum
globally. These names emphasize that the semantic difference between
these operations is more than just NaN-propagation.

Reviewers: arsenm, aheejin, dschuff, javed.absar

Subscribers: jholewinski, sdardis, wdng, sbc100, jgravelle-google, jrtc27, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D53112

llvm-svn: 345218
2018-10-24 22:49:55 +00:00
Matthias Braun 4f82406c46 SelectionDAG: Reuse bigger sized constants in memset expansion.
When implementing memset's today we often see this pattern:
$x0 = MOV 0xXYXYXYXYXYXYXYXY
store $x0, ...
$w1 = MOV 0xXYXYXYXY
store $w1, ...

We first create a 64bit constant in a 64bit register with all bytes the
same and then create a 32bit constant with all bytes the same in a 32bit
register. In many targets we could just access the lower byte of the
64bit register instead.

- Ideally this would be handled by the ConstantHoist pass but it runs
  too early when memset isn't expanded yet.
- The memset expansion code already had this optimization implemented,
  however SelectionDAG constantfolding would constantfold the
  "trunc(bigconstnat)" pattern to "smallconstant".
- This patch makes the memset expansion mark the constant as Opaque and
  stop DAGCombiner from constant folding in this situation. (Similar to
  how ConstantHoisting marks things as Opaque to avoid folding
  ADD/SUB/etc.)

Differential Revision: https://reviews.llvm.org/D53181

llvm-svn: 345102
2018-10-23 23:19:23 +00:00
Matt Arsenault 687ec75d10 DAG: Change behavior of fminnum/fmaxnum nodes
Introduce new versions that follow the IEEE semantics
to help with legalization that may need quieted inputs.

There are some regressions from inserting unnecessary
canonicalizes when these are matched from fast math
fcmp + select which should be fixed in a future commit.

llvm-svn: 344914
2018-10-22 16:27:27 +00:00
Sanjay Patel f6a160a102 [SelectionDAG] allow undefs when matching splat constants
And use that to transform fsub with zero constant operands.
The integer part isn't used yet, but it is proposed for use in
D44548, so adding both enhancements here makes that 
patch simpler.

llvm-svn: 343865
2018-10-05 17:42:19 +00:00
Fangrui Song 0cac726a00 llvm::sort(C.begin(), C.end(), ...) -> llvm::sort(C, ...)
Summary: The convenience wrapper in STLExtras is available since rL342102.

Reviewers: dblaikie, javed.absar, JDevlieghere, andreadb

Subscribers: MatzeB, sanjoy, arsenm, dschuff, mehdi_amini, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, javed.absar, gbedwell, jrtc27, mgrang, atanasyan, steven_wu, george.burgess.iv, dexonsmith, kristina, jsji, llvm-commits

Differential Revision: https://reviews.llvm.org/D52573

llvm-svn: 343163
2018-09-27 02:13:45 +00:00
Mikael Nilsson 9c8e35174e Run VerifyDAGDiverence in debug only
VerifyDAGDiverence costs compilation time, avoid running it in non-debug
builds.

Differential Revision: https://reviews.llvm.org/D52454

llvm-svn: 343086
2018-09-26 09:25:45 +00:00
Sanjay Patel 10c11b867a [x86] avoid 256-bit andnp that requires insert/extract with AVX1 (PR37449)
This is the final (I hope!) problem pattern mentioned in PR37749:
https://bugs.llvm.org/show_bug.cgi?id=37749

We are trying to avoid an AVX1 sinkhole caused by having 256-bit bitwise logic ops but no other 256-bit integer ops. 
We've already solved the simple logic ops, but 'andn' is an x86 special. I looked at alternative solutions like 
extending the generic DAG combine or trying to wait until the ANDNP node is created, but those are bigger patches 
that can over-reach. Ie, splitting to 128-bit does not look like a win in most cases with >1 256-bit op.

The pattern matching is cluttered with bitcasts because of our i64 element canonicalization. For the affected test, 
we have this vector-type-legalized sequence:

        t29: v8i32 = concat_vectors t27, t28
      t30: v4i64 = bitcast t29
        t18: v8i32 = BUILD_VECTOR Constant:i32<-1>, Constant:i32<-1>, ...
      t31: v4i64 = bitcast t18
    t32: v4i64 = xor t30, t31
      t9: v8i32 = BUILD_VECTOR Constant:i32<255>, Constant:i32<255>, ...
    t34: v4i64 = bitcast t9
  t35: v4i64 = and t32, t34
t36: v8i32 = bitcast t35
      t37: v4i32 = extract_subvector t36, Constant:i64<0>
      t38: v4i32 = extract_subvector t36, Constant:i64<4>

Differential Revision: https://reviews.llvm.org/D52318

llvm-svn: 343008
2018-09-25 19:09:34 +00:00
Sanjay Patel 8a1227ccc8 [SelectionDAG] replace duplicated peekThroughBitcast helper functions; NFCI
x86 had 2 versions of peekThroughBitcast. DAGCombiner had 1. Plus, it had a 1-off implementation for the one-use variant.
Move the x86 versions of the code to SelectionDAG, so we don't have different copies of the code. 
No functional change intended.

I'm putting this next to isBitwiseNot() because I am planning to use it in there. Another option is next to the
helpers in the ISD namespace (eg, ISD::isConstantSplatVector()). But if there's no good reason for those to be 
there, I'd prefer to pull other helpers over to SelectionDAG in follow-up steps.

Differential Revision: https://reviews.llvm.org/D52285

llvm-svn: 342669
2018-09-20 17:34:08 +00:00
Sanjay Patel fdc0de19cb [SelectionDAG] allow vector types with isBitwiseNot()
The test diff in not-and-simplify.ll is from a use in SimplifyDemandedBits,
and the test diff in add.ll is from a DAGCombiner transform.

llvm-svn: 342594
2018-09-19 21:48:30 +00:00
Adrian Prantl 16f58d1850 Fix debug info for SelectionDAG legalization of DAG nodes with two results.
This patch fixes the debug info handling for SelectionDAG legalization
of DAG nodes with two results. When an replaced SDNode has more than
one result, transferDbgValues was always copying the SDDbgValue from
the first result and attaching them to all members. In reality
SelectionDAG::ReplaceAllUsesWith() is given an array of SDNodes
(though the type signature doesn't make this obvious (cf. the call
site code in ReplaceNode()).

rdar://problem/44162227

Differential Revision: https://reviews.llvm.org/D52112

llvm-svn: 342264
2018-09-14 19:38:45 +00:00
Scott Linder cab029f474 [CodeGen] Fix remaining zext() assertions in SelectionDAG
Fix remaining cases not committed in https://reviews.llvm.org/D49574

Differential Revision: https://reviews.llvm.org/D50659

llvm-svn: 341380
2018-09-04 16:33:34 +00:00
Matt Arsenault ca25b58957 DAG: Handle extract_vector_elt in isKnownNeverNaN
llvm-svn: 341317
2018-09-03 14:01:03 +00:00
Nicolai Haehnle 35617ed4cb [NFC] Rename the DivergenceAnalysis to LegacyDivergenceAnalysis
Summary:
This is patch 1 of the new DivergenceAnalysis (https://reviews.llvm.org/D50433).

The purpose of this patch is to free up the name DivergenceAnalysis for the new generic
implementation. The generic implementation class will be shared by specialized
divergence analysis classes.

Patch by: Simon Moll

Reviewed By: nhaehnle

Subscribers: jvesely, jholewinski, arsenm, nhaehnle, mgorny, jfb, llvm-commits

Differential Revision: https://reviews.llvm.org/D50434

Change-Id: Ie8146b11be2c50d5312f30e11c7a3036a15b48cb
llvm-svn: 341071
2018-08-30 14:21:36 +00:00
Craig Topper 9f42726cc7 [X86] Support v2i32 gather/scatter indices with -x86-experimental-vector-widening-legalization
Summary: This is split out from D41062 to cover the code in LegalVectorTypes.cpp

Reviewers: RKSimon, spatel, efriedma

Reviewed By: efriedma

Subscribers: sdardis, jvesely, nhaehnle, jrtc27, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D51337

llvm-svn: 340891
2018-08-29 02:12:49 +00:00
Nirav Dave 113f2b9058 [DAG] Avoid recomputing Divergence checks. NFCI.
When making multiple updates to the same SDNode, recompute node
divergence only once after all changes have been made.

llvm-svn: 340852
2018-08-28 18:13:00 +00:00
Nirav Dave 0b8cb46e0b [DAG] Fix updateDivergence calculation
Check correct SDNode when deciding if we should update the divergence
property.

llvm-svn: 340851
2018-08-28 18:12:35 +00:00
Craig Topper a11a3b3818 [SelectionDAG][X86] Reorder the operands the MaskedStoreSDNode to put the value first.
Summary:
Previously the value being stored is the last operand in SDNode. This causes the type legalizer to visit the mask operand before the value operand. The type legalizer was more complicated because of this since we want the type of the value to drive the decisions.

This patch moves the value to be the first operand so we visit it first during type legalization. It also simplifies the type legalization code accordingly.

X86 is currently the only in tree target that uses this SDNode. Not sure if there are any users out of tree.

Reviewers: RKSimon, delena, hfinkel, eli.friedman

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50402

llvm-svn: 340689
2018-08-25 17:48:17 +00:00
Justin Bogner fbbd4366a6 [SDAG] Add versions of computeKnownBits that return a value
Having the KnownBits as an output parameter is kind of awkward to use
and a holdover from when it was two separate APInts. Instead, just
return a KnownBits object.

I'm leaving the existing interface in place for now, since updating
the callers all at once would be thousands of lines of diff.

llvm-svn: 340594
2018-08-24 02:42:24 +00:00
Simon Pilgrim 1a00042270 [SelectionDAG] Reuse the Op's VT. NFCI.
llvm-svn: 340173
2018-08-20 13:44:03 +00:00
Simon Pilgrim 5b78c9d58d [SelectionDAG] Add partial sign-bit support to ComputeNumSignBits for BITCAST nodes
Only adds support to the existing 'large element' scalar/vector to 'small element' vector bitcasts.

Handle the case where the sign bit extends to only part of the small elements.

llvm-svn: 340169
2018-08-20 13:05:48 +00:00
Simon Pilgrim 5b936ec89e [SelectionDAG] Add basic demanded elements support to ComputeNumSignBits for BITCAST nodes
Only adds support to the existing 'large element' scalar/vector to 'small element' vector bitcasts.

The next step would be to support cases where the large elements aren't all sign bits, and determine the small element equivalent based on the demanded elements.

llvm-svn: 340143
2018-08-19 17:47:50 +00:00
Matt Arsenault 25e51540e1 DAG: Fix isKnownNeverNaN for basic non-sNaN cases
fadd/fsub/fmul need to worry about infinities as well
as fdiv.

llvm-svn: 340085
2018-08-17 21:19:22 +00:00
Chandler Carruth 66654b72c9 [SDAG] Remove the reliance on MI's allocation strategy for
`MachineMemOperand` pointers attached to `MachineSDNodes` and instead
have the `SelectionDAG` fully manage the memory for this array.

Prior to this change, the memory management was deeply confusing here --
The way the MI was built relied on the `SelectionDAG` allocating memory
for these arrays of pointers using the `MachineFunction`'s allocator so
that the raw pointer to the array could be blindly copied into an
eventual `MachineInstr`. This creates a hard coupling between how
`MachineInstr`s allocate their array of `MachineMemOperand` pointers and
how the `MachineSDNode` does.

This change is motivated in large part by a change I am making to how
`MachineFunction` allocates these pointers, but it seems like a layering
improvement as well.

This would run the risk of increasing allocations overall, but I've
implemented an optimization that should avoid that by storing a single
`MachineMemOperand` pointer directly instead of allocating anything.
This is expected to be a net win because the vast majority of uses of
these only need a single pointer.

As a side-effect, this makes the API for updating a `MachineSDNode` and
a `MachineInstr` reasonably different which seems nice to avoid
unexpected coupling of these two layers. We can map between them, but we
shouldn't be *surprised* at where that occurs. =]

Differential Revision: https://reviews.llvm.org/D50680

llvm-svn: 339740
2018-08-14 23:30:32 +00:00
Scott Linder 35213793bc [CodeGen] Fix assert in SelectionDAG::computeKnownBits
Fix SelectionDAG::computeKnownBits asserting when handling EXTRACT_SUBVECTOR
when zero extending the demanded elements mask if it is already as long as the
source vector.

Differential Revision: https://reviews.llvm.org/D49574

llvm-svn: 339600
2018-08-13 18:44:21 +00:00
Craig Topper 17989208a9 [SelectionDAG][X86] Rename getValue to getPassThru for gather SDNodes.
getValue is more meaningful name for scatter than it is for gather. Split them and use getPassThru for gather.

llvm-svn: 339096
2018-08-07 06:13:40 +00:00
Matt Arsenault c3dc8e65e2 DAG: Enhance isKnownNeverNaN
Add a parameter for testing specifically for
sNaNs - at least one instruction pattern on AMDGPU
needs to check specifically for this.

Also handle more cases, and add a target hook
for custom nodes, similar to the hooks for known
bits.

llvm-svn: 338910
2018-08-03 18:27:52 +00:00
Michael Berg d3ce4c3d94 [NFC] small addendum to r334242, FMF propagation
llvm-svn: 338604
2018-08-01 18:06:49 +00:00
Simon Pilgrim a3548c960e [SelectionDAG] Make binop reduction matcher available to all targets
There is nothing x86-specific about this code, so it'd be nice to make this available for other targets to use in the future (and get it out of X86ISelLowering!).

Differential Revision: https://reviews.llvm.org/D50083

llvm-svn: 338586
2018-08-01 16:52:28 +00:00
Craig Topper 8da280f50b [SelectionDAG] Add MLOAD/MSTORE/MGATHER/MSCATTER to AddNodeIDCustom to properly calculate their folding set ID to allow them to be CSEd.
llvm-svn: 338080
2018-07-26 22:40:24 +00:00
Vedant Kumar b572f64212 [DebugInfo] LowerDbgDeclare: Add derefs when handling CallInst users
LowerDbgDeclare inserts a dbg.value before each use of an address
described by a dbg.declare. When inserting a dbg.value before a CallInst
use, however, it fails to append DW_OP_deref to the DIExpression.

The DW_OP_deref is needed to reflect the fact that a dbg.value describes
a source variable directly (as opposed to a dbg.declare, which relies on
pointer indirection).

This patch adds in the DW_OP_deref where needed. This results in the
correct values being shown during a debug session for a program compiled
with ASan and optimizations (see https://reviews.llvm.org/D49520). Note
that ConvertDebugDeclareToDebugValue is already correct -- no changes
there were needed.

One complication is that SelectionDAG is unable to distinguish between
direct and indirect frame-index (FRAMEIX) SDDbgValues. This patch also
fixes this long-standing issue in order to not regress integration tests
relying on the incorrect assumption that all frame-index SDDbgValues are
indirect. This is a necessary fix: the newly-added DW_OP_derefs cannot
be lowered properly otherwise. Basically the fix prevents a direct
SDDbgValue with DIExpression(DW_OP_deref) from being dereferenced twice
by a debugger. There were a handful of tests relying on this incorrect
"FRAMEIX => indirect" assumption which actually had incorrect
DW_AT_locations: these are all fixed up in this patch.

Testing:

- check-llvm, and an end-to-end test using lldb to debug an optimized
  program.
- Existing unit tests for DIExpression::appendToStack fully cover the
  new DIExpression::append utility.
- check-debuginfo (the debug info integration tests)

Differential Revision: https://reviews.llvm.org/D49454

llvm-svn: 338069
2018-07-26 20:56:53 +00:00
Simon Pilgrim 075b04a55f [SelectionDAG] Add constant buildvector support to isKnownNeverZero
This allows us to use SelectionDAG::isKnownNeverZero in DAGCombiner::visitREM (visitSDIVLike/visitUDIVLike handle the checking for constants).

llvm-svn: 336779
2018-07-11 09:56:41 +00:00
Craig Topper e3b0c7e5bd [SelectionDAG] Add VT consistency checks to the creation of ISD::FMA.
This is similar to what is done for binops. I don't know if this would have helped us catch the bug fixed in r336566 earlier or not, but I figured it couldn't hurt.

llvm-svn: 336576
2018-07-09 18:23:55 +00:00
Simon Pilgrim 23f9eddabe [SelectionDAG] Split float and integer isKnownNeverZero tests
Splits off isKnownNeverZeroFloat to handle +/- 0 float cases.

This will make it easier to be more aggressive with the integer isKnownNeverZero tests (similar to ValueTracking), use computeKnownBits etc.

Differential Revision: https://reviews.llvm.org/D48969

llvm-svn: 336492
2018-07-07 18:17:14 +00:00
Vedant Kumar b725c69f12 [SelectionDAG] Remove debug locations from ConstantSD(FP)Nodes
This removes debug locations from ConstantSDNode and ConstantSDFPNode.

When this kind of node is materialized we no longer create a line table
entry which jumps back to the constant's first point of use. This makes
single-stepping behavior smoother, and it matches the model used by IR,
where Constants have no locations. See this thread for more context:

  http://lists.llvm.org/pipermail/llvm-dev/2018-June/124164.html

I'd like to handle constant BuildVectorSDNodes and to try to eliminate
passing SDLocs to SelectionDAG::getConstant*() in follow-up commits.

Differential Revision: https://reviews.llvm.org/D48468

llvm-svn: 335497
2018-06-25 17:06:18 +00:00
Michael Berg 7b993d762f Utilize new SDNode flag functionality to expand current support for fadd
Summary: This patch originated from D46562 and is a proper subset, with some issues addressed.

Reviewers: spatel, hfinkel, wristow, arsenm, javed.absar

Reviewed By: spatel

Subscribers: wdng, nhaehnle

Differential Revision: https://reviews.llvm.org/D47909

llvm-svn: 334996
2018-06-18 23:44:59 +00:00
Michael Berg 77b5be7ec6 propagate fast math flags via IR on fma and sub expressions
Summary: This change uses fmf subflags to guard fma optimizations as well as unsafe. These changes originated from D46483 and have been simplified via getNode.

Reviewers: spatel, arsenm, hfinkel, javed.absar

Reviewed By: spatel

Subscribers: nemanjai, wdng

Differential Revision: https://reviews.llvm.org/D47388

llvm-svn: 334242
2018-06-07 22:49:09 +00:00
Michael Berg 96925fe0df guard fneg with fmf sub flags
Summary: This change uses fmf subflags to guard optimizations as well as unsafe. These changes originated from D46483.

Reviewers: spatel, hfinkel

Reviewed By: spatel

Subscribers: nemanjai

Differential Revision: https://reviews.llvm.org/D47389

llvm-svn: 334037
2018-06-05 18:49:47 +00:00
Scott Linder ba81d7f1eb [CodeGen] Always update divergence in SelectionDAG::UpdateNodeOperands
Some overloads failed to update divergence.

Differential Revision: https://reviews.llvm.org/D47148

llvm-svn: 333947
2018-06-04 20:19:45 +00:00
Sanjay Patel 17a870f07c [DAG] fold FP binops with undef operands to NaN
This is the FP sibling of D43141 with the corresponding IR change in rL327212.

We can't propagate undef here because if a variable operand is a NaN, these 
binops must propagate NaN. Neither global nor node-level fast-math makes a 
difference. If we have 'nnan', I think later folds can turn the NaN into undef.

The tests in X86/fp-undef.ll are meant to be the definitive verification for 
these folds - everything reduces identically now.

The other test changes are collateral damage. They may need to be altered to
preserve their intent.

Differential Revision: https://reviews.llvm.org/D47026

llvm-svn: 332920
2018-05-21 23:54:19 +00:00
Sirish Pande cabe50a308 [AArch64] Gangup loads and stores for pairing.
Keep loads and stores together (target defines how many loads
and stores to gang up), such that it will help in pairing
and vectorization.

Differential Revision https://reviews.llvm.org/D46477

llvm-svn: 332482
2018-05-16 15:36:52 +00:00
Nicola Zaghen d34e60ca85 Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624

llvm-svn: 332240
2018-05-14 12:53:11 +00:00
Shiva Chen cd070cdc94 [DebugInfo] Convert intrinsic llvm.dbg.label to MachineInstr.
In order to convert LLVM IR to MachineInstr, we need a new TargetOpcode,
DBG_LABEL, to ‘lower’ intrinsic llvm.dbg.label. The patch
creates this new TargetOpcode and convert intrinsic llvm.dbg.label to
MachineInstr through SelectionDAG.

In SelectionDAG, debug information is stored in SDDbgInfo. We create a
new data member of SDDbgInfo for labels and use the new data member,
SDDbgLabel, to create DBG_LABEL MachineInstr.

The new DBG_LABEL MachineInstr uses label metadata from LLVM IR as its
parameter. So, the backend could get metadata information of labels from
DBG_LABEL MachineInstr.

Differential Revision: https://reviews.llvm.org/D45341

Patch by Hsiangkai Wang.

llvm-svn: 331842
2018-05-09 02:41:08 +00:00
Aaron Smith 47589e09dd [SelectionDAG] Transfer DbgValues when casts are optimized in SelectionDAG::getNode
Summary:
getNode optimizes (ext (trunc x)) to x and the dbgvalue node on trunc is lost. The fix calls transferDbgValues to add the dbgvalue to x.

Add DebugInfo/AArch64/dbg-value-i16.ll

Patch by Sejong Oh!

Reviewers: aprantl, javed.absar, llvm-commits, vsk

Reviewed By: aprantl, vsk

Subscribers: kristof.beyls, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D46348

llvm-svn: 331665
2018-05-07 20:15:50 +00:00
Adrian Prantl 5f8f34e459 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
Bjorn Pettersson abafca619b [SelectionDAG] Improve selection of DBG_VALUE using a PHI node result
Summary:
When building the selection DAG at ISel all PHI nodes are
selected and lowered to Machine Instruction PHI nodes before
we start to create any SDNodes. So there are no SDNodes for
values produced by the PHI nodes.

In the past when selecting a dbg.value intrinsic that uses
the value produced by a PHI node we have been handling such
dbg.value intrinsics as "dangling debug info". I.e. we have
not created a SDDbgValue node directly, because there is
no existing SDNode for the PHI result, instead we deferred
the creationg of a SDDbgValue until we found the first use
of the PHI result.

The old solution had a couple of flaws. The position of the
selected DBG_VALUE instruction would end up quite late in a
basic block, and for example not directly after the PHI node
as in the LLVM IR input. And in case there were no use at all
in the basic block the dbg.value could be dropped completely.

This patch introduces a new VREG kind of SDDbgValue nodes.
It is similar to a SDNODE kind of node, but it refers directly
to a virtual register and not a SDNode. When we do selection
for a dbg.value that is using the result of a PHI node we
can do a lookup of the virtual register directly (as it already
is determined for the PHI node) and create a SDDbgValue node
immediately instead of delaying the selection until we find a
use.

This should fix a problem with losing debug info at ISel
as seen in PR37234 (https://bugs.llvm.org/show_bug.cgi?id=37234).
It does not resolve PR37234 completely, because the debug info
is dropped later on in the BranchFolder (see D46184).

Reviewers: #debug-info, aprantl

Reviewed By: #debug-info, aprantl

Subscribers: rnk, gbedwell, aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D46129

llvm-svn: 331182
2018-04-30 14:37:39 +00:00
Daniel Neilson 9863b48d4e [SelectionDAG] Refactor lowering of atomic memory intrinsics.
Summary:
This just refactors the lowering of the atomic memory intrinsics to more
closely match the code patterns used in the lowering of the non-atomic
memory intrinsics. Specifically, we encapsulate the lowering in
SelectionDAG::getAtomicMem*() functions rather than embedding
the code directly in the SelectionDAGBuilder code.

llvm-svn: 330603
2018-04-23 15:40:37 +00:00
Roman Lebedev 9792838905 [SelectionDAG][NFC] haveNoCommonBitsSet(): add FIXME notes
As suggested in https://reviews.llvm.org/D45631#1068338

llvm-svn: 330102
2018-04-15 18:59:38 +00:00
Mandeep Singh Grang e92f0cfe34 [CodeGen] Change std::sort to llvm::sort in response to r327219
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.

Reviewers: bogner, rnk, MatzeB, RKSimon

Reviewed By: rnk

Subscribers: JDevlieghere, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D45133

llvm-svn: 329435
2018-04-06 18:08:42 +00:00
Craig Topper 2fa1436206 [IR][CodeGen] Remove dependency on EVT from IR/Function.cpp. Move EVT to CodeGen layer.
Currently EVT is in the IR layer only because of Function.cpp needing a very small piece of the functionality of EVT::getEVTString(). The rest of EVT is used in codegen making CodeGen a better place for it.

The previous code converted a Type* to EVT and then called getEVTString. This was only expected to handle the primitive types from Type*. Since there only a few primitive types, we can just print them as strings directly.

Differential Revision: https://reviews.llvm.org/D45017

llvm-svn: 328806
2018-03-29 17:21:10 +00:00
David Blaikie 36a0f226b1 Fix layering by moving ValueTypes.h from CodeGen to IR
ValueTypes.h is implemented in IR already.

llvm-svn: 328397
2018-03-23 23:58:31 +00:00
David Blaikie 13e77db2df Fix layering of MachineValueType.h by moving it from CodeGen to Support
This is used by llvm tblgen as well as by LLVM Targets, so the only
common place is Support for now. (maybe we need another target for these
sorts of things - but for now I'm at least making them correct & we can
make them better if/when people have strong feelings)

llvm-svn: 328395
2018-03-23 23:58:25 +00:00
Jonas Paulsson e9f7fa83d5 [SelectionDAG] Handle big endian target BITCAST in computeKnownBits()
The BITCAST handling in computeKnownBits() previously only worked for little
endian.

This patch reverses the iteration over elements for a big endian target which
allows this to work in this case also.

SystemZ test case.

Review: Eli Friedman
https://reviews.llvm.org/D44249

llvm-svn: 327764
2018-03-17 08:04:00 +00:00
Sebastian Pop b4bd0a404f [x86][aarch64] ask the backend whether it has a vector blend instruction
The code to match and produce more x86 vector blends was enabled for all
architectures even though the transform may pessimize the code for other
architectures that do not provide a vector blend instruction.

Added an aarch64 testcase to check that a VZIP instruction is generated instead
of byte movs.

Differential Revision: https://reviews.llvm.org/D44118

llvm-svn: 327132
2018-03-09 14:29:21 +00:00
Eric Liu 47f42c2167 Fix an unused variable warning introduced by rr326703. NFC
llvm-svn: 326732
2018-03-05 18:36:39 +00:00
Alexander Timofeev 2e5eeceeb7 Pass Divergence Analysis data to Selection DAG to drive divergence
dependent instruction selection.

Differential revision: https://reviews.llvm.org/D35267

llvm-svn: 326703
2018-03-05 15:12:21 +00:00
Simon Pilgrim be72fe1fda [SelectionDAG] Move matchUnaryPredicate/matchBinaryPredicate into SelectionDAGNodes.h
This allows us to improve vector constant matching in more DAG code (backends, TargetLowering etc.).

Differential Revision: https://reviews.llvm.org/D43466

llvm-svn: 325815
2018-02-22 18:45:13 +00:00
Simon Pilgrim 70eb508605 [SelectionDAG] ComputeKnownBits - add support for SMIN+SMAX clamp patterns
If we have a clamp pattern, SMIN(SMAX(X, LO),HI) or SMAX(SMIN(X, HI),LO) then we can deduce that the number of signbits (zeros/ones) will be at least the minimum of the LO and HI constants.

ComputeKnownBits equivalent of D43338.

Differential Revision: https://reviews.llvm.org/D43463

llvm-svn: 325521
2018-02-19 18:08:16 +00:00
Simon Pilgrim 6740df386c Fix Wparentheses warning. NFCI
llvm-svn: 325451
2018-02-17 22:45:56 +00:00
Simon Pilgrim 7fae42eb27 [SelectionDAG] ComputeNumSignBits - add support for SMIN+SMAX clamp patterns
If we have a clamp pattern, SMIN(SMAX(X, LO),HI) or SMAX(SMIN(X, HI),LO) then we can deduce that the number of signbits will be at least the minimum of the LO and HI constants.

I haven't bothered with the UMIN/UMAX equivalent as (1) we don't have any current use cases and (2) I wonder if we'd be better off immediately falling back for ComputeKnownBits for UMIN/UMAX which already has optimization patterns useful for unsigned cases.

Differential Revision: https://reviews.llvm.org/D43338

llvm-svn: 325450
2018-02-17 22:19:50 +00:00
Simon Pilgrim 1eb5c455c9 [SelectionDAG] Pull out repeated Op.getOpcode(). NFCI.
llvm-svn: 325253
2018-02-15 15:31:00 +00:00
Elena Demikhovsky 945b7e5aa6 Adding a width of the GEP index to the Data Layout.
Making a width of GEP Index, which is used for address calculation, to be one of the pointer properties in the Data Layout.
p[address space]:size:memory_size:alignment:pref_alignment:index_size_in_bits.
The index size parameter is optional, if not specified, it is equal to the pointer size.

Till now, the InstCombiner normalized GEPs and extended the Index operand to the pointer width.
It works fine if you can convert pointer to integer for address calculation and all registered targets do this.
But some ISAs have very restricted instruction set for the pointer calculation. During discussions were desided to retrieve information for GEP index from the Data Layout.
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120416.html

I added an interface to the Data Layout and I changed the InstCombiner and some other passes to take the Index width into account.
This change does not affect any in-tree target. I added tests to cover data layouts with explicitly specified index size.

Differential Revision: https://reviews.llvm.org/D42123

llvm-svn: 325102
2018-02-14 06:58:08 +00:00
Sanjay Patel 907b58530f [DAG] fix type of undef returned by getNode()
The bug has been lying dormant, but apparently was never exposed, until
after rL324941 because we didn't return the correct result 
for shifts with undef operands.

llvm-svn: 325010
2018-02-13 14:55:07 +00:00
Sanjay Patel 014c000f6a [DAG] make binops with undef operands consistent with IR
This started by noticing that scalar and vector types were producing different results with div ops in PR36305:
https://bugs.llvm.org/show_bug.cgi?id=36305

...but the problem is bigger. I couldn't keep it straight without a table, so I'm attaching that as a PDF to 
the review. The x86 tests in undef-ops.ll correspond to that table.

Green means that instsimplify and the DAG agree on the result for all types.
Red means the DAG was returning undef when IR was not.
Yellow means the DAG was returning a non-undef result when IR returned undef.

This patch assumes that we're currently doing the right thing in IR.

Note: I couldn't find any problems with lowering vector constants as the code comments were warning, 
but those comments were written long ago in rL36413 .

Differential Revision: https://reviews.llvm.org/D43141

llvm-svn: 324941
2018-02-12 21:37:27 +00:00
Oliver Stannard 02f08c9d1f [AArch64] Improve v8.1-A code-gen for atomic load-and
Armv8.1-A added an atomic load-clear instruction (which performs bitwise
and with the complement of it's operand), but not a load-and
instruction. Our current code-generation for atomic load-and always
inserts an MVN instruction to invert its argument, even if it could be
folded into a constant or another instruction.

This adds lowering early in selection DAG to convert a load-and
operation into an xor with -1 and a load-clear, allowing the normal DAG
optimisations to work on it.

To do this, I've had to add a new ISD opcode, ATOMIC_LOAD_CLR. I don't
see any easy way to do this with an AArch64-specific ISD node, because
the code-generation for atomic operations assumes the SDNodes are of
type AtomicSDNode.

I've left the old tablegen patterns in because they are still needed for
global isel.

Differential revision: https://reviews.llvm.org/D42478

llvm-svn: 324908
2018-02-12 17:03:11 +00:00
Craig Topper 9b611e436f [SelectionDAG] Add a helper function for creating a boolean constant based on the target's boolean content
Many in SimplifySetCC and FoldSetCC try to create true or false constants. Some of them query getBooleanContents to figure out whether to use all ones or just 1 for true. But many places do not check and just use 1 without ensuring the VT has an i1 scalar type. Note sure if those places only trigger before type legalization so they only see an i1
type?

To cleanup the inconsistency and reduce some duplicated code, this patch adds a getBoolConstant method to SelectionDAG that takes are of querying getBooleanContents and doing the right thing.

Differential Revision: https://reviews.llvm.org/D43037

llvm-svn: 324634
2018-02-08 18:55:14 +00:00
Simon Pilgrim 4df6499f10 [SelectionDAG] Don't use simple VT in generic shuffle code
Better to assume that any value type may be commuted, not just MVTs.

No test case right now, but discovered while investigating possible shuffle combines.

llvm-svn: 324179
2018-02-03 21:34:42 +00:00
Jonas Paulsson ad089fe46e [SelectionDAG] Add an assert in getNode() for EXTRACT_VECTOR_ELT.
When getNode() is called to create an EXTRACT_VECTOR_ELT, assert that
the result VT is at least as wide as the vector element type.

Review: Eli Friedman
llvm-svn: 324061
2018-02-02 08:21:53 +00:00
Ulrich Weigand 5605be9e50 [SelectionDAG] Teach computeKnownBits about ATOMIC_CMP_SWAP_WITH_SUCCESS boolean return value
The second return value of ATOMIC_CMP_SWAP_WITH_SUCCESS is known to be a
boolean, and should therefore be treated by computeKnownBits just like
the second return values of SMULO / UMULO.

Differential Revision: https://reviews.llvm.org/D42067

llvm-svn: 322985
2018-01-19 20:47:14 +00:00
Craig Topper af4eb17223 [SelectionDAG][X86] Explicitly store the scale in the gather/scatter ISD nodes
Currently we infer the scale at isel time by analyzing whether the base is a constant 0 or not. If it is we assume scale is 1, else we take it from the element size of the pass thru or stored value. This seems a little weird and I think it makes more sense to make it explicit in the DAG rather than doing tricky things in the backend.

Most of this patch is just making sure we copy the scale around everywhere.

Differential Revision: https://reviews.llvm.org/D40055

llvm-svn: 322210
2018-01-10 19:16:05 +00:00
Sanjay Patel 37e28e40cb [SelectionDAG] lower math intrinsics to finite version of libcalls when possible (PR35672)
Ingredients in this patch:
1. Add HANDLE_LIBCALL defs for finite mathlib functions that correspond to LLVM intrinsics.
2. Plumbing to send TargetLibraryInfo down to SelectionDAGLegalize.
3. Relaxed math and library checking in SelectionDAGLegalize::ConvertNodeToLibcall() to choose finite libcalls.

There was a bug about determining the availability of the finite calls that should be fixed with:
rL322010

Not in this patch:
This doesn't resolve the question/bug of clang creating the intrinsic IR in the first place.
There's likely follow-up work needed to support the long double variants better.
There's room for improvement to reduce the code duplication.
Create finite calls that don't originate from a corresponding intrinsic or DAG node?

Differential Revision: https://reviews.llvm.org/D41338

llvm-svn: 322087
2018-01-09 15:41:00 +00:00
Nirav Dave 6e2d03d410 [DAG] Teach BaseIndexOffset to correctly handle with indexed operations
BaseIndexOffset address analysis incorrectly ignores offsets folded
into indexed memory operations causing potential errors in alias
analysis of pre-indexed operations.

Reviewers: efriedma, RKSimon, hfinkel, jyknight

Subscribers: hiraditya, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D41701

llvm-svn: 322003
2018-01-08 16:21:35 +00:00
Simon Pilgrim ec0a2fb703 [DAGCombine] Handle out of range EXTRACT_VECTOR_ELT indices
Handle this in DAGCombiner::visitEXTRACT_VECTOR_ELT the same as we already do in SelectionDAG::getNode and use APInt instead of getZExtValue.

This should also fix oss-fuzz #4910

llvm-svn: 321767
2018-01-03 22:42:33 +00:00
Dimitry Andric 2fb6134305 Avoid modifying DbgInfo while looping in salvageDebuginfo
Summary:
I have been getting rather difficult to reproduce SIGBUS crashes when
compiling certain FreeBSD sources, and their stack traces pointed
squarely at `SelectionDAG::salvageDebugInfo()`:

```
Core was generated by `/usr/obj/share/dim/src/freebsd/clang600-import/amd64.amd64/tmp/usr/bin/cc -cc1 -'.
Program terminated with signal SIGBUS, Bus error.
#0  isInvalidated () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h:115
115       bool isInvalidated() const { return Invalid; }
(gdb) bt
#0  isInvalidated () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h:115
#1  salvageDebugInfo () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:7116
#2  0x00000000033b2516 in operator() () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:3595
#3  __invoke<(lambda at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:3593:59) &, llvm::SDNode *, llvm::SDNode *> () at /usr/include/c++/v1/type_traits:4323
#4  __call<(lambda at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:3593:59) &, llvm::SDNode *, llvm::SDNode *> () at /usr/include/c++/v1/__functional_base:349
#5  operator() () at /usr/include/c++/v1/functional:1562
#6  0x00000000033b0817 in operator() () at /usr/include/c++/v1/functional:1916
#7  NodeDeleted () at /share/dim/src/freebsd/clang600-import/contrib/llvm/include/llvm/CodeGen/SelectionDAG.h:293
#8  0x0000000003529dde in RemoveDeadNodes () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:610
#9  0x00000000035556df in MorphNodeTo () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:6794
#10 0x00000000033a9acc in MorphNode () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:2594
#11 0x00000000033ac80b in SelectCodeCommon () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:3601
#12 0x00000000023d464b in SelectCode () at /usr/obj/share/dim/src/freebsd/clang600-import/amd64.amd64/tmp/obj-tools/lib/clang/libllvm/X86GenDAGISel.inc:282902
#13 Select () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp:3072
#14 0x00000000033a5afa in DoInstructionSelection () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:988
#15 0x00000000033a4e1a in CodeGenAndEmitDAG () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:868
#16 0x00000000033a2643 in SelectAllBasicBlocks () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:1624
#17 0x000000000339f158 in runOnMachineFunction () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:466
#18 0x00000000023d03c4 in runOnMachineFunction () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp:175
#19 0x00000000035cc8c2 in runOnFunction () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/MachineFunctionPass.cpp:62
#20 0x00000000030dca9a in runOnFunction () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/IR/LegacyPassManager.cpp:1520
#21 0x00000000030dccf3 in runOnModule () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/IR/LegacyPassManager.cpp:1541
#22 0x00000000030dd228 in runOnModule () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/IR/LegacyPassManager.cpp:1597
#23 run () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/IR/LegacyPassManager.cpp:1700
#24 0x00000000014db578 in EmitAssembly () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/CodeGen/BackendUtil.cpp:815
#25 EmitBackendOutput () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/CodeGen/BackendUtil.cpp:1181
#26 0x00000000014d5b26 in HandleTranslationUnit () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/CodeGen/CodeGenAction.cpp:292
#27 0x0000000001c4c332 in ParseAST () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/Parse/ParseAST.cpp:159
#28 0x00000000015d546c in Execute () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/Frontend/FrontendAction.cpp:897
#29 0x0000000001cec311 in ExecuteAction () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/Frontend/CompilerInstance.cpp:991
#30 0x00000000014b4f81 in ExecuteCompilerInvocation () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:252
#31 0x00000000014aa73f in cc1_main () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/tools/driver/cc1_main.cpp:221
#32 0x00000000014b2928 in ExecuteCC1Tool () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/tools/driver/driver.cpp:309
#33 main () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/tools/driver/driver.cpp:388
(gdb) frame 1
#1  salvageDebugInfo () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:7116
7116        if (DV->isInvalidated())
(gdb) disassemble
Dump of assembler code for function salvageDebugInfo():
[...]
   0x0000000003557348 <+744>:   nopl   0x0(%rax,%rax,1)
   0x0000000003557350 <+752>:   mov    (%r12),%r13
=> 0x0000000003557354 <+756>:   cmpb   $0x0,0x31(%r13)
   0x0000000003557359 <+761>:   jne    0x35573b0 <salvageDebugInfo()+848>
(gdb) info registers
[...]
r13            0x5a5a5a5a5a5a5a5a       6510615555426900570
```

The `0x5a5a5a5a5a5a5a5a` value in `r13` indicates the memory was either
uninitialized, or already freed.

Unfortunately I do not have a simple self-contained test case for this.
However, it seems pretty clear that the call to `AddDbgValue()` in
`salvageDebugInfo()` causes the problems, since it modifies
`SelectionDag::DbgInfo` while looping through one of its DenseMaps:

```
void SelectionDAG::salvageDebugInfo(SDNode &N) {
[...]
  for (auto DV : GetDbgValues(&N)) {
    if (DV->isInvalidated())
      continue;
[...]
        AddDbgValue(Clone, N0.getNode(), false);
[...]
  }
}
```

At least, if I comment out the `AddDbgValue()` call, the crashes go
away.  I propose to change this function slightly, similar to the
`SelectionDAG::transferDbgValues()` function just above it, to save the
cloned SDDbgValues in a separate SmallVector, and only call
AddDbgValue() on them after the for loop is done.

Reviewers: aprantl, bogner, bkramer, davide

Reviewed By: davide

Subscribers: davide, krytarowski, JDevlieghere, emaste, llvm-commits

Differential Revision: https://reviews.llvm.org/D41589

llvm-svn: 321545
2017-12-28 23:42:44 +00:00
Craig Topper c077ae68c3 [SelectionDAG] Add creating new node debug messages for load, store, gather, and scatter.
llvm-svn: 321540
2017-12-28 19:46:16 +00:00
Craig Topper 1f2f265fc1 [SelectionDAG] Teach SelectionDAG::getNode to constant fold zext/aext/sext of constant build vectors.
llvm-svn: 321414
2017-12-23 20:21:29 +00:00
Matthias Braun f1caa2833f MachineFunction: Return reference from getFunction(); NFC
The Function can never be nullptr so we can return a reference.

llvm-svn: 320884
2017-12-15 22:22:58 +00:00
Craig Topper 23951ec2cd [SelectionDAG] Make getNode calls that take an ArrayRef of SDValue for operands call NewSDValueDbgMsg.
This makes it work better with some build_vector and concat_vectors creations.

Adjust the NewSDValueDbgMsg in getConstant to avoid duplicating the print when it calls getSplatBuildVector since getSplatBuildVector didn't trigger a print before.

llvm-svn: 320783
2017-12-15 01:03:45 +00:00
Matt Arsenault 1117133687 DAG: Expose all MMO flags in getTgtMemIntrinsic
Rather than adding more bits to express every
MMO flag you could want, just directly use the
MMO flags. Also fixes using a bunch of bool arguments to
getMemIntrinsicNode.

On AMDGPU, buffer and image intrinsics should always
have MODereferencable set, but currently there is no
way to do that directly during the initial intrinsic
lowering.

llvm-svn: 320746
2017-12-14 21:39:51 +00:00
Adrian Prantl d13170174c Generalize llvm::replaceDbgDeclare and actually support the use-case that
is mentioned in the documentation (inserting a deref before the plus_uconst).

llvm-svn: 320203
2017-12-08 21:58:18 +00:00
Craig Topper 67217d7eb4 [SelectionDAG] Teach computeKnownBits some improvements to ISD::SRL with a non-splat constant shift amount.
If we have a non-splat constant shift amount, the minimum shift amount can be used to infer the number of zero upper bits of the result. There's probably a lot more that we can do here, but this
fixes a case where I wanted to infer the sign bit as zero when all the shift amounts are non-zero.

llvm-svn: 319639
2017-12-04 05:38:42 +00:00
Craig Topper f3470e1ed4 [SelectionDAG] Use the inlined APInt shift methods since we've already bounds checked the shift.
The version that takes APInt is out of line. The 'unsigned' version optimizes for the common case of single word APInts.

llvm-svn: 319628
2017-12-03 03:07:09 +00:00
Yaxun Liu 494770403a CodeGen: Fix pointer info in SplitVecOp_EXTRACT_VECTOR_ELT/SplitVecRes_INSERT_VECTOR_ELT
Two issues found when doing codegen for splitting vector with non-zero alloca addr space:

DAGTypeLegalizer::SplitVecRes_INSERT_VECTOR_ELT/SplitVecOp_EXTRACT_VECTOR_ELT uses dummy pointer info for creating
SDStore. Since one pointer operand contains multiply and add, InferPointerInfo is unable to
infer the correct pointer info, which ends up with a dummy pointer info for the target to lower
store and results in isel failure. The fix is to introduce MachinePointerInfo::getUnknownStack to
represent MachinePointerInfo which is known in alloca address space but without other information.

TargetLowering::getVectorElementPointer uses value type of pointer in addr space 0 for
multiplication of index and then add it to the pointer. However the pointer may be in an addr
space which has different size than addr space 0. The fix is to use the pointer value type for
index multiplication.

Differential Revision: https://reviews.llvm.org/D39758

llvm-svn: 319622
2017-12-02 22:13:22 +00:00
Craig Topper 820ce04377 [SelectionDAG] Add a debug message when vector_shuffle nodes are created.
We print a debug message when most nodes are created, but getVectorShuffle was missing.

llvm-svn: 319085
2017-11-27 19:54:57 +00:00
Vedant Kumar 4d7f2b02d6 [SelectionDAG] Consolidate (t|T)ransferDbgValues methods, NFC (reapply)
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.

This was reverted in r318455 because some newly introduced asserts,
which I thought were NFC, were firing. I filed PR35338. For now I've
weakened the asserts.

Testing: check-llvm, check-clang, and a stage2 Rel+Deb build of clang

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

llvm-svn: 318498
2017-11-17 01:48:33 +00:00
David Blaikie b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
Vedant Kumar 53418797fd Revert "[SelectionDAG] Consolidate (t|T)ransferDbgValues methods, NFC."
This reverts commit r318448. It looks like some of the asserts need to
be weakened.

http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-autoconf/builds/16296

llvm-svn: 318455
2017-11-16 21:08:51 +00:00
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
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
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
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
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
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
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
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
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
Simon Pilgrim 1bc62f03a5 [SelectionDAG] Add VSELECT support to ComputeNumSignBits
llvm-svn: 316457
2017-10-24 16:38:38 +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 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
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 90b76211d3 [SelectionDAG} Use KnownBits::isUnknown and hasConflict. NFC
llvm-svn: 315154
2017-10-07 17:07:48 +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
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
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
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
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
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
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
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
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
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
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
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
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 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
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
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
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
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
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
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
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
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
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
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
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
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
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
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 a6ed1b2f12 Use SDValue::getOperand() helper. NFCI.
llvm-svn: 302896
2017-05-12 13:20:24 +00:00
Simon Pilgrim a4a13a0da0 Strip trailing whitespace. NFCI.
llvm-svn: 302784
2017-05-11 10:03:05 +00:00
Amara Emerson cf9daa33a7 Introduce experimental generic intrinsics for horizontal vector reductions.
- This change allows targets to opt-in to using them instead of the log2
  shufflevector algorithm.
- The SLP and Loop vectorizers have the common code to do shuffle reductions
  factored out into LoopUtils, and now have a unified interface for generating
  reductions regardless of the preference of the target. LoopUtils now uses TTI
  to determine what kind of reductions the target wants to handle.
- For CodeGen, basic legalization support is added.

Differential Revision: https://reviews.llvm.org/D30086

llvm-svn: 302514
2017-05-09 10:43:25 +00:00
Craig Topper f0aeee01c3 [KnownBits] Add wrapper methods for setting and clear all bits in the underlying APInts in KnownBits.
This adds routines for reseting KnownBits to unknown, making the value all zeros or all ones. It also adds methods for querying if the value is zero, all ones or unknown.

Differential Revision: https://reviews.llvm.org/D32637

llvm-svn: 302262
2017-05-05 17:36:09 +00:00
Craig Topper d4d09fd73d [SelectionDAG] Improve known bits support for CTPOP.
This is based on the same concept from ValueTracking's version of computeKnownBits.

llvm-svn: 302110
2017-05-04 04:33:27 +00:00
Craig Topper d938fd1397 [KnownBits] Add zext, sext, and trunc methods to KnownBits
This patch adds zext, sext, and trunc methods to KnownBits and uses them where possible.

Differential Revision: https://reviews.llvm.org/D32784

llvm-svn: 302088
2017-05-03 22:07:25 +00:00
Simon Pilgrim 89ad89cc73 [SelectionDAG] Improve support for promotion of <1 x fX> floating point argument types (PR31088)
PR31088 demonstrated that we were assuming that only integers require promotion from <1 x iX> types, when in fact float types may require it as well - in this case half floats.

This patch adds support for extension/truncation for both integer and float types.

Differential Revision: https://reviews.llvm.org/D32391

llvm-svn: 301910
2017-05-02 10:33:08 +00:00
Craig Topper 6b1b630a98 [SelectionDAG] Use known ones to provide a better bound for the known zeros for CTTZ/CTLZ operations.
This is the SelectionDAG version of D32521. If know where at least one 1 is located in the input to these intrinsics we can place an upper bound on the number of bits needed to represent the count and thus increase the number of known zeros in the output.

I think we can also refine this further for CTTZ_UNDEF/CTLZ_UNDEF by assuming that the answer will never be BitWidth. I've left this out for now because it caused other test failures across multiple targets. Usually because of turning ADD into OR based on this new information.

I'll fix CTPOP in a future patch.

Differential Revision: https://reviews.llvm.org/D32692

llvm-svn: 301806
2017-05-01 16:08:06 +00:00
Amara Emerson d28f0cd448 Generalize the specialized flag-carrying SDNodes by moving flags into SDNode.
This removes BinaryWithFlagsSDNode, and flags are now all passed by value.

Differential Revision: https://reviews.llvm.org/D32527

llvm-svn: 301803
2017-05-01 15:17:51 +00:00
Amaury Sechet 8ac81f3924 Do not legalize large add with addc/adde, introduce addcarry and do it with uaddo/addcarry
Summary: As per discution on how to get better codegen an large int legalization, it became clear that using a glue for the carry was preventing several desirable optimizations. Passing the carry down as a value allow for more flexibility.

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

Subscribers: igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D29872

llvm-svn: 301775
2017-04-30 19:24:09 +00:00
Craig Topper 778f57b4f1 [APInt] Replace calls to setBits with more specific calls to setBitsFrom and setLowBits where possible.
llvm-svn: 301768
2017-04-30 07:44:58 +00:00
Craig Topper ca48af3c87 [KnownBits] Add methods for determining if the known bits represent a negative/nonnegative number and add methods for changing the negative/nonnegative state
Summary: This patch adds isNegative, isNonNegative for querying whether the sign bit is known. It also adds makeNegative and makeNonNegative for controlling the sign bit.

Reviewers: RKSimon, spatel, davide

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32651

llvm-svn: 301747
2017-04-29 16:43:11 +00:00
Craig Topper 24db6b800f [APInt] Add clearSignBit method. Use it and setSignBit in a few places. NFCI
llvm-svn: 301656
2017-04-28 16:58:05 +00:00
Simon Pilgrim 7ae9419dc0 [DAGCombiner] Add ComputeNumSignBits vector demanded elements support to ASHR and INSERT_VECTOR_ELT (reapplied)
Reapplied r299221 after fix for nondeterminism in ThinLTO builder (rL301599), with extra check for implicit truncation of inserted element.

llvm-svn: 301644
2017-04-28 13:21:18 +00:00
Craig Topper f42b23f7d8 [ValueTracking] Convert computeKnownBitsFromRangeMetadata to use KnownBits struct.
llvm-svn: 301626
2017-04-28 06:28:56 +00:00
Craig Topper d0af7e8ab8 [SelectionDAG] Use KnownBits struct in DAG's computeKnownBits and simplifyDemandedBits
This patch replaces the separate APInts for KnownZero/KnownOne with a single KnownBits struct. This is similar to what was done to ValueTracking's version recently.

This is largely a mechanical transformation from KnownZero to Known.Zero.

Differential Revision: https://reviews.llvm.org/D32569

llvm-svn: 301620
2017-04-28 05:31:46 +00:00
Craig Topper 0e03e74e95 [SelectionDAG] Use various APInt methods to reduce temporary APInt creation
This patch uses various APInt methods to reduce the number of temporary APInts. These were all found while working through converting SelectionDAG's computeKnownBits to also use the KnownBits struct recently added to the ValueTracking version.

llvm-svn: 301618
2017-04-28 04:57:59 +00:00
Craig Topper 24e71017aa [APInt] Use inplace shift methods where possible. NFCI
llvm-svn: 301612
2017-04-28 03:36:24 +00:00
Craig Topper b45eabcf82 [ValueTracking] Introduce a KnownBits struct to wrap the two APInts for computeKnownBits
This patch introduces a new KnownBits struct that wraps the two APInt used by computeKnownBits. This allows us to treat them as more of a unit.

Initially I've just altered the signatures of computeKnownBits and InstCombine's simplifyDemandedBits to pass a KnownBits reference instead of two separate APInt references. I'll do similar to the SelectionDAG version of computeKnownBits/simplifyDemandedBits as a separate patch.

I've added a constructor that allows initializing both APInts to the same bit width with a starting value of 0. This reduces the repeated pattern of initializing both APInts. Once place default constructed the APInts so I added a default constructor for those cases.

Going forward I would like to add more methods that will work on the pairs. For example trunc, zext, and sext occur on both APInts together in several places. We should probably add a clear method that can be used to clear both pieces. Maybe a method to check for conflicting information. A method to return (Zero|One) so we don't write it out everywhere. Maybe a method for (Zero|One).isAllOnesValue() to determine if all bits are known. I'm sure there are many other methods we can come up with.

Differential Revision: https://reviews.llvm.org/D32376

llvm-svn: 301432
2017-04-26 16:39:58 +00:00
Sanjay Patel a4b4e9388c [DAG] add FIXME comments for splat detection; NFC
llvm-svn: 301403
2017-04-26 13:27:57 +00:00
Sanjay Patel 7a8317c09a [DAG] fix formatting of isConstantSplat(); NFC
llvm-svn: 301366
2017-04-25 23:33:28 +00:00
Simon Pilgrim ab0446332e [SelectionDAG] Recognise splat vector isKnownToBeAPowerOfTwo one/sign bit shift cases.
llvm-svn: 301303
2017-04-25 12:29:07 +00:00
Renato Golin 4abfb3d741 Revert "[APInt] Fix a few places that use APInt::getRawData to operate within the normal API."
This reverts commit r301105, 4, 3 and 1, as a follow up of the previous
revert, which broke even more bots.

For reference:
Revert "[APInt] Use operator<<= where possible. NFC"
Revert "[APInt] Use operator<<= instead of shl where possible. NFC"
Revert "[APInt] Use ashInPlace where possible."

PR32754.

llvm-svn: 301111
2017-04-23 12:15:30 +00:00
Craig Topper cdd5ae6676 [APInt] Use operator<<= where possible. NFC
llvm-svn: 301104
2017-04-23 05:43:02 +00:00
Craig Topper ae9672c96d [APInt] Use ashInPlace where possible.
llvm-svn: 301101
2017-04-23 03:45:59 +00:00
Benjamin Kramer 997fd5eeb4 [Recycler] Add asan/msan annotations.
This enables use after free and uninit memory checking for memory
returned by a recycler. SelectionDAG currently relies on the opcode of a
free'd node being ISD::DELETED_NODE, so poke a hole in the asan poison
for SDNode opcodes. This means that we won't find some issues, but only
in SDag.

llvm-svn: 300868
2017-04-20 18:29:37 +00:00
Yaxun Liu 5d977f8ed4 CodeGen: Let frame index value type match alloca addr space
Recently alloca address space has been added to data layout. Due to this
change, pointer returned by alloca may have different size as pointer in
address space 0.

However, currently the value type of frame index is assumed to be of the
same size as pointer in address space 0.

This patch fixes that.

Most targets assume alloca returning pointer in address space 0, which
is the default alloca address space. Therefore it is NFC for them.

AMDGCN target with amdgiz environment requires this change since it
assumes alloca returning pointer to addr space 5 and its size is 32,
which is different from the size of pointer in addr space 0 which is 64.

Differential Revision: https://reviews.llvm.org/D32021

llvm-svn: 300864
2017-04-20 18:15:34 +00:00
Craig Topper bcfd2d1789 [APInt] Rename getSignBit to getSignMask
getSignBit is a static function that creates an APInt with only the sign bit set. getSignMask seems like a better name to convey its functionality. In fact several places use it and then store in an APInt named SignMask.

Differential Revision: https://reviews.llvm.org/D32108

llvm-svn: 300856
2017-04-20 16:56:25 +00:00
Amara Emerson 5054782052 [MVT][SVE] Scalable vector MVTs (1/3)
This patch adds a few helper functions to obtain new vector
value types based on existing ones without needing to care
about whether they are scalable or not.

I've confined their use to a few common locations right now,
and targets that don't have scalable vectors should never
need to care about these.

Patch by Graham Hunter.

Differential Revision: https://reviews.llvm.org/D32017

llvm-svn: 300838
2017-04-20 13:08:17 +00:00
Galina Kistanova 2cc97d92ce Temporarily revert r299221 to fix nondeterminism in ThinLTO builder.
llvm-svn: 300783
2017-04-19 23:16:14 +00:00
Craig Topper 9b71a402c2 [APInt] Cast calls to add/sub/mul overflow methods to void if only their overflow bool out param is used.
This is preparation for a clang change to improve the [[nodiscard]] warning to not be ignored on methods that return a class marked [[nodiscard]] that are defined in the class itself. See D32207.

We should consider adding wrapper methods to APInt that return the overflow flag directly and discard the APInt result. This would eliminate the void casts and the need to create a bool before the call to pass to the out param.

llvm-svn: 300758
2017-04-19 21:09:45 +00:00
Craig Topper fc947bcfba [APInt] Use lshrInPlace to replace lshr where possible
This patch uses lshrInPlace to replace code where the object that lshr is called on is being overwritten with the result.

This adds an lshrInPlace(const APInt &) version as well.

Differential Revision: https://reviews.llvm.org/D32155

llvm-svn: 300566
2017-04-18 17:14:21 +00:00
Jonas Paulsson 45c936ef86 [SelectionDAG] NFC patch removing a redundant check.
Since the BUILD_VECTOR has already been checked by
isBuildVectorOfConstantSDNodes() in SelectionDAG::getNode() for a
SIGN_EXTEND_INREG, it can be assumed that Op is always either undef or a
ConstantSDNode, and Ops.size() will always equal VT.getVectorNumElements().

llvm-svn: 299647
2017-04-06 13:00:37 +00:00
Jonas Paulsson 38a2da92bc [DAGCombiner] Don't make a BUILD_VECTOR with operands of illegal type.
When DAGCombiner visits a SIGN_EXTEND_INREG of a BUILD_VECTOR with
constant operands, a new BUILD_VECTOR node will be created transformed
constants.

Llvm-stress found a case where the new BUILD_VECTOR had constant operands
of an illegal type, because the (legal) element type is in fact not a legal
scalar type.

This patch changes this so that the new BUILD_VECTOR has the same operand
type as the old one.

Review: Eli Friedman, Nirav Dave
https://bugs.llvm.org//show_bug.cgi?id=32422

llvm-svn: 299540
2017-04-05 13:45:37 +00:00
Simon Pilgrim 1cdbfe44b1 [DAGCombiner] Add ComputeNumSignBits vector demanded elements support to ASHR and INSERT_VECTOR_ELT
Followup to D31311

llvm-svn: 299221
2017-03-31 14:21:50 +00:00
Simon Pilgrim 3c81c34d8d [DAGCombiner] Add vector demanded elements support to ComputeNumSignBits
Currently ComputeNumSignBits returns the minimum number of sign bits for all elements of vector data, when we may only be interested in one/some of the elements.

This patch adds a DemandedElts argument that allows us to specify the elements we actually care about. The original ComputeNumSignBits implementation calls with a DemandedElts demanding all elements to match current behaviour. Scalar types set this to 1.

I've only added support for BUILD_VECTOR and EXTRACT_VECTOR_ELT so far, all others will default to demanding all elements but can be updated in due course.

Followup to D25691.

Differential Revision: https://reviews.llvm.org/D31311

llvm-svn: 299219
2017-03-31 13:54:09 +00:00
Simon Pilgrim 37b536e4b3 [DAGCombiner] Add vector demanded elements support to computeKnownBitsForTargetNode
Follow up to D25691, this sets up the plumbing necessary to support vector demanded elements support in known bits calculations in target nodes.

Differential Revision: https://reviews.llvm.org/D31249

llvm-svn: 299201
2017-03-31 11:24:16 +00:00
Ahmed Bougacha 6dd6082472 [CodeGen] Pass SDAG an ORE, and replace FastISel stats with remarks.
In the long-term, we want to replace statistics with something
finer-grained that lets us gather per-function data.
Remarks are that replacement.

Create an ORE instance in SelectionDAGISel, and pass it to
SelectionDAG.

SelectionDAG was used so that we can emit remarks from all
SelectionDAG-related code, including TargetLowering and DAGCombiner.
This isn't used in the current patch but Adam tells me he's interested
for the fp-contract combines.

Use the ORE instance to emit FastISel failures as remarks (instead of
the mix of dbgs() dumps and statistics that we currently have).

Eventually, we want to have an API that tells us whether remarks are
enabled (http://llvm.org/PR32352) so that we don't emit expensive
remarks (in this case, dumping IR) when it's not needed.  For now, use
'isEnabled' as a crude replacement.

This does mean that the replacement for '-fast-isel-verbose' is now
'-pass-remarks-missed=isel'.  Additionally, clang users also need to
enable remark diagnostics, using '-Rpass-missed=isel'.

This also removes '-fast-isel-verbose2': there are no static statistics
that we want to only enable in asserts builds, so we can always use
the remarks regardless of the build type.

Differential Revision: https://reviews.llvm.org/D31405

llvm-svn: 299093
2017-03-30 17:49:58 +00:00
Sanjay Patel 9747d8070b [DAG] fix formatting; NFC
llvm-svn: 298950
2017-03-28 22:25:25 +00:00
Simon Pilgrim dbc94db3f3 Apply clang-format as commented in D31311. NFCI.
llvm-svn: 298751
2017-03-24 23:47:41 +00:00
Simon Pilgrim 8424df7dea Fix constant folding of fp2int to large integers
We make the assumption in most of our constant folding code that a fp2int will target an integer of 128-bits or less, calling the APFloat::convertToInteger with only uint64_t[2] of raw bits for the result.

Fuzz testing (PR24662) showed that we don't handle other cases at all, resulting in stack overflows and all sorts of crashes.

This patch uses the APSInt version of APFloat::convertToInteger instead to better handle such cases.

Differential Revision: https://reviews.llvm.org/D31074

llvm-svn: 298226
2017-03-19 16:50:25 +00:00
Nirav Dave ac6081cb67 Make library calls sensitive to regparm module flag (Fixes PR3997).
Reviewers: mkuper, rnk

Subscribers: mehdi_amini, jyknight, aemerson, llvm-commits, rengolin

Differential Revision: https://reviews.llvm.org/D27050

llvm-svn: 298179
2017-03-18 00:44:07 +00:00
Eli Friedman 46ddab3810 [SelectionDAG] Remove redundant stores more aggressively.
Handle TokenFactors more aggressively in
SDValue::reachesChainWithoutSideEffects.  This isn't really a
very effective change anymore because of other changes to
chain handling, but it's a cheap check, and the expanded
comments are still useful.

It might be possible to loosen the hasOneUse() requirement with a
deeper analysis, but a naive implementation of that check would be
expensive.

Differential Revision: https://reviews.llvm.org/D29845

llvm-svn: 298156
2017-03-17 22:15:50 +00:00
Simon Pilgrim 5a68d401c7 [SelectionDAG] Add SelectionDAG.computeKnownBits test support for ISD::ABS
llvm-svn: 298108
2017-03-17 17:45:36 +00:00
Craig Topper bcb6093610 [CodeGen] Use APInt::setLowBits/setHighBits/setBitsFrom in more places
This patch replaces ORs with getHighBits/getLowBits etc. with setLowBits/setHighBits/setBitsFrom.

In a few of the places we weren't ORing, but the KnownZero/KnownOne vectors were already initialized to zero. We exploit this in most places already there were just some that were inconsistent.

Differential Revision: https://reviews.llvm.org/D30965

llvm-svn: 297860
2017-03-15 16:53:53 +00:00
Simon Pilgrim 018eedd9a5 [SelectionDAG] Support BUILD_VECTOR implicit truncation in SelectionDAG::ComputeNumSignBits (PR32273)
llvm-svn: 297852
2017-03-15 16:22:24 +00:00
Nuno Lopes ae455c562d fix gcc -Wmisleading-indentation [NFC]
llvm-svn: 297816
2017-03-15 09:33:33 +00:00
Simon Pilgrim cf2da96c82 [SelectionDAG] Add a signed integer absolute ISD node
Reduced version of D26357 - based on the discussion on llvm-dev about canonicalization of UMIN/UMAX/SMIN/SMAX as well as ABS I've reduced that patch to just the ABS ISD node (with x86/sse support) to improve basic combines and lowering.

ARM/AArch64, Hexagon, PowerPC and NVPTX all have similar instructions allowing us to make this a generic opcode and move away from the hard coded tablegen patterns which makes it tricky to match more complex patterns.

At the moment this patch doesn't attempt legalization as we only create an ABS node if its legal/custom.

Differential Revision: https://reviews.llvm.org/D29639

llvm-svn: 297780
2017-03-14 21:26:58 +00:00
Sanjay Patel 8dd99dce6c [DAG] vector div/rem with any zero element in divisor is undef
This is the backend counterpart to:
https://reviews.llvm.org/rL297390
https://reviews.llvm.org/rL297409
and follow-up to:
https://reviews.llvm.org/rL297384

It surprised me that we need to duplicate the check in FoldConstantArithmetic and FoldConstantVectorArithmetic, 
but one or the other doesn't catch all of the test cases. There is an existing code comment about merging those 
someday.

Differential Revision: https://reviews.llvm.org/D30826

llvm-svn: 297762
2017-03-14 18:06:28 +00:00
Amaury Sechet d1ec5d54cf Use setBits in SelectionDAG
Summary: As per title.

Reviewers: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30836

llvm-svn: 297559
2017-03-11 11:24:03 +00:00
Simon Pilgrim 7dedbfa89d [SelectionDAG] Add support for BUILD_VECTOR to ComputeNumSignBits
llvm-svn: 297492
2017-03-10 18:36:46 +00:00
Amaury Sechet 62e0759d56 [SelectionDAG] Make SelectionDAG aware of the known bits in USUBO and SSUBO and SUBC.
Summary:
Depends on D30379

This improves the state of things for the sub class of operation.

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

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30436

llvm-svn: 297482
2017-03-10 17:26:44 +00:00
Amaury Sechet 69fa16c810 [SelectionDAG] Make SelectionDAG aware of the known bits in UADDO and SADDO.
Summary: As per title. This is extracted from D29872 and I threw SADDO in.

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

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D30379

llvm-svn: 297479
2017-03-10 17:06:52 +00:00
Simon Pilgrim b02667c469 [APInt] Add APInt::insertBits() method to insert an APInt into a larger APInt
We currently have to insert bits via a temporary variable of the same size as the target with various shift/mask stages, resulting in further temporary variables, all of which require the allocation of memory for large APInts (MaskSizeInBits > 64).

This is another of the compile time issues identified in PR32037 (see also D30265).

This patch adds the APInt::insertBits() helper method which avoids the temporary memory allocation and masks/inserts the raw bits directly into the target.

Differential Revision: https://reviews.llvm.org/D30780

llvm-svn: 297458
2017-03-10 13:44:32 +00:00
Sanjay Patel df21979db7 [DAG] recognize div/rem by 0 as undef before trying constant folding
As discussed in the review thread for rL297026, this is actually 2 changes that 
would independently fix all of the test cases in the patch:

1. Return undef in FoldConstantArithmetic for div/rem by 0.
2. Move basic undef simplifications for div/rem (simplifyDivRem()) before 
   foldBinopIntoSelect() as a matter of efficiency.

I will handle the case of vectors with any zero element as a follow-up. That change
is the DAG sibling for D30665 + adding a check of vector elements to FoldConstantVectorArithmetic().

I'm deleting the test for PR30693 because it does not test for the actual bug any more
(dangers of using bugpoint).

Differential Revision:
https://reviews.llvm.org/D30741

llvm-svn: 297384
2017-03-09 15:02:25 +00:00
Simon Pilgrim 9f5c251d57 [X86][SSE] Lower 128-bit vectors to SIGN/ZERO_EXTEND_VECTOR_IN_REG ops
As described on PR31712, we miss a variety of legalization combines because we lower these to X86ISD::VSEXT/VZEXT despite them having the same functionality. This patch makes 128-bit (SSE41) SIGN/ZERO_EXTEND_VECTOR_IN_REG ops legal, adds the necessary tablegen plumbing and uses a helper 'getExtendInVec' to decide when to use SIGN/ZERO_EXTEND_VECTOR_IN_REG or VSEXT/VZEXT.

We're missing a couple of shuffle combines that will be added in a future patch for review.

Later patches can then support the AVX2 cases as a mixture of SIGN/ZERO_EXTEND and SIGN/ZERO_EXTEND_VECTOR_IN_REG, and then finally deal with the AVX512 cases.

Differential Revision: https://reviews.llvm.org/D30549

llvm-svn: 296985
2017-03-05 09:57:20 +00:00
Simon Pilgrim 6dfab414db Use APInt::setBits instead of OR'ing in a separate APInt::getBitsSet call
llvm-svn: 296886
2017-03-03 17:03:52 +00:00
Amaury Sechet 71f511fd1e [DAGCombiner] mulhi + 1 never overflow.
Summary:
This can be used to optimize large multiplications after legalization.

Depends on D29565

Reviewers: mkuper, spatel, RKSimon, zvi, bkramer, aaboud, craig.topper

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29587

llvm-svn: 296711
2017-03-01 23:44:17 +00:00
Simon Pilgrim bfb1747806 [DAGCombine] Allow vector constant folding of any value type before type legalization
The patch comes in 2 parts:

1 - it makes use of the SelectionDAG::NewNodesMustHaveLegalTypes flag to tell when it can safely constant fold illegal types.

2 - it correctly resets SelectionDAG::NewNodesMustHaveLegalTypes at the start of each call to SelectionDAGISel::CodeGenAndEmitDAG so all the pre-legalization stages can make use of it - not just the first basic block that gets handled.

Fix for PR30760

Differential Revision: https://reviews.llvm.org/D29568

llvm-svn: 294749
2017-02-10 14:37:25 +00:00
Amaury Sechet e674f5c758 Add ADDC to SelectionDAG::computeKnownBits and ComputeNumSignBits.
Summary: As per title.

Reviewers: bkramer, sunfish, lattner, RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29521

llvm-svn: 294188
2017-02-06 14:59:06 +00:00
Amaury Sechet 8a3b32941d [DAGCombiner] Make DAGCombiner smarter about overflow
Summary: Leverage it to transform addc into add.

Reviewers: mkuper, spatel, RKSimon, zvi

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29524

llvm-svn: 294187
2017-02-06 14:54:49 +00:00
Simon Pilgrim bfd4495512 [X86][SSE] Combine shuffle nodes with multiple uses if all the users are being combined.
Currently we only combine shuffle nodes if they have a single user to prevent us from causing code bloat by splitting the shuffles into several different combines.

We don't take into account that in some cases we will already have combined all the users during recursively calling up the shuffle tree.

This patch keeps a list of all the shuffle nodes that have been combined so far and permits combining of further shuffle nodes if all its users are in that list.

Differential Revision: https://reviews.llvm.org/D29399

llvm-svn: 294183
2017-02-06 13:44:45 +00:00
Matt Arsenault 0c687390fe DAG: Constant fold fp16_to_fp/fp16_to_fp
This fixes emitting conversions of constants on targets
without legal f16 that need to use these for legalization.

llvm-svn: 293499
2017-01-30 16:57:41 +00:00
Craig Topper 135da1faf5 [SelectionDAG] Make SDNode::getConstantOperandVal an inline method.
It's operation already exists manually in many places without using the method.

llvm-svn: 293421
2017-01-29 06:08:02 +00:00
Craig Topper ff272ad4f3 [SelectionDAG] Teach getNode to simplify a couple easy cases of EXTRACT_SUBVECTOR
Summary:
This teaches getNode to simplify extracting from Undef. This is similar to what is done for EXTRACT_VECTOR_ELT. It also adds support for extracting from CONCAT_VECTOR when we can reuse one of the inputs to the concat. These seem like simple non-target specific optimizations.

For X86 we currently handle undef in extractSubvector, but not all EXTRACT_SUBVECTOR creations go through there.

Ultimately, my motivation here is to simplify extractSubvector and remove custom lowering for EXTRACT_SUBVECTOR since we don't do anything but handle undef and BUILD_VECTOR optimizations, but those should be DAG combines.

Reviewers: RKSimon, delena

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D29000

llvm-svn: 292876
2017-01-24 02:36:59 +00:00
Simon Pilgrim fb32eea1b4 [SelectionDAG] Improve knownbits handling of UMIN/UMAX (PR31293)
This patch improves the knownbits logic for unsigned integer min/max opcodes.

For UMIN we know that the result will have the maximum of the inputs' known leading zero bits in the result, similarly for UMAX the maximum of the inputs' leading one bits.

This is particularly useful for simplifying clamping patterns,. e.g. as SSE doesn't have a uitofp instruction we want to use sitofp instead where possible and for that we need to confirm that the top bit is not set.

Differential Revision: https://reviews.llvm.org/D28853

llvm-svn: 292528
2017-01-19 22:41:22 +00:00
Matt Arsenault f411071d63 DAG: Consider nnan in isKnownNeverNaN
llvm-svn: 292328
2017-01-18 02:10:08 +00:00
Simon Pilgrim 3e91519a1c [SelectionDAG] Add knownbits support for BITREVERSE
llvm-svn: 292130
2017-01-16 14:49:26 +00:00
Simon Pilgrim db73dbcc7c [SelectionDAG] Add support for BITREVERSE constant folding
We were relying on constant folding of the legalized instructions to do what constant folding we had previously

llvm-svn: 292114
2017-01-16 13:39:00 +00:00
Malcolm Parsons 17d266bc96 Remove unused lambda captures. NFC
llvm-svn: 291916
2017-01-13 17:12:16 +00:00
Matt Arsenault def496c04b Remove unused CONVERT_RNDSAT intrinsics
llvm-svn: 291607
2017-01-10 22:38:02 +00:00
Simon Dardis 548a53f5ee [mips] Fix Mips MSA instrinsics
The usage of some MIPS MSA instrinsics that took immediates could crash LLVM
during lowering. This patch addresses that behaviour. Crucially this patch
also makes the use of intrinsics with out of range immediates as producing an
internal error.

The ld,st instrinsics would trigger an assertion failure for MIPS64 as their
lowering would attempt to add an i32 offset to a i64 pointer.

Reviewers: vkalintiris, slthakur

Differential Revision: https://reviews.llvm.org/D25438

llvm-svn: 291571
2017-01-10 16:40:57 +00:00
Simon Pilgrim 0d66d29678 [SelectionDAG] Early out from computeKnownBits when we know we will have no common bits.
Avoid extra (recursive) calls to computeKnownBits if we already know that there are no common known bits.

llvm-svn: 290490
2016-12-24 12:59:35 +00:00
Matt Arsenault 485dacd90c DAG: Add helper for testing constant values
There are helpers for testing for constant or constant build_vector,
and for splat ConstantFP vectors, but not for a constantfp or
non-splat ConstantFP vector.

llvm-svn: 290317
2016-12-22 04:39:45 +00:00
Joel Jones 8980ba643e Fix name typo in SelectonDAG
llvm-svn: 289969
2016-12-16 18:22:54 +00:00
Simon Pilgrim 05ab8ffc7e [DAGCombiner] Try to use SelectionDAG::isKnownToBeAPowerOfTwo instead of just APInt::isPowerOf2
Generalize sdiv/udiv/srem/urem combines using APInt::isPowerOf2, which only works for const/splat-const values, to call SelectionDAG::isKnownToBeAPowerOfTwo instead which recognises many more cases.

Added a DAGCombiner::BuildLogBase2 helper since PowerOf2 combines often involve taking the log2 of such a value.

Differential Revision: https://reviews.llvm.org/D27714

llvm-svn: 289654
2016-12-14 15:08:13 +00:00
Stephan Bergmann 17c7f70362 Replace APFloatBase static fltSemantics data members with getter functions
At least the plugin used by the LibreOffice build
(<https://wiki.documentfoundation.org/Development/Clang_plugins>) indirectly
uses those members (through inline functions in LLVM/Clang include files in turn
using them), but they are not exported by utils/extract_symbols.py on Windows,
and accessing data across DLL/EXE boundaries on Windows is generally
problematic.

Differential Revision: https://reviews.llvm.org/D26671

llvm-svn: 289647
2016-12-14 11:57:17 +00:00
Simon Pilgrim 9dc67c0101 [SelectionDAG] computeKnownBits - simplified knownbits sign extension. NFCI.
We don't need to extract+test the sign bit of the known ones/zeros, we can use sext which will handle all of this.

llvm-svn: 289534
2016-12-13 13:36:27 +00:00
Simon Pilgrim 040a36c176 [SelectionDAG] Add support for EXTRACT_SUBVECTOR to ComputeNumSignBits
Pre-commit as discussed on D27657

llvm-svn: 289425
2016-12-12 10:29:43 +00:00
Simon Pilgrim 54945a12ec [SelectionDAG] Add ability for computeKnownBits to peek through bitcasts from 'large element' scalar/vector to 'small element' vector.
Extension to D27129 which already supported bitcasts from 'small element' vector to 'large element' scalar/vector types.

llvm-svn: 289329
2016-12-10 17:00:00 +00:00
Simon Pilgrim 017b7a71d8 [SelectionDAG] Add knownbits support for EXTRACT_VECTOR_ELT opcodes (REAPPLIED)
Reapplied with fix for PR31323 - X86 SSE2 vXi16 multiplies for illegal types were creating CONCAT_VECTORS nodes with vector inputs that might not total the number of elements in the result type.

llvm-svn: 289232
2016-12-09 17:53:11 +00:00
Simon Pilgrim bf9c0e7434 [SelectionDAG] Use SelectionDAG.getBuildVector helper. NFCI.
Makes interception of BUILD_VECTOR creation easier for debugging.

llvm-svn: 289218
2016-12-09 15:23:41 +00:00
Simon Pilgrim 15f1f828b5 [SelectionDAG] Add additional checks to CONCAT_VECTORS creation
Part of the work for PR31323 - add extra asserts checking that the input vectors are of consistent type and result in the correct number of vector elements.

llvm-svn: 289214
2016-12-09 14:27:52 +00:00
Simon Pilgrim e4050a2961 [SelectionDAG] Add partial BITCAST support to computeKnownBits
Adds support for bitcasting a little endian 'small element' vector to 'large element' scalar/vector (e.g. v16i8 to v4i32 or v2i32 to i64), which is required for PR30845. We extract the knownbits for each 'small element' part and concatenate the results together.

We can add support for big endian and 'large element' scalar/vector to 'small element' vector bitcasting once we have test cases for them.

Differential Revision: https://reviews.llvm.org/D27129

llvm-svn: 289200
2016-12-09 10:13:45 +00:00
Daniel Jasper f51e05ffbc Revert "[SelectionDAG] Add knownbits support for EXTRACT_VECTOR_ELT opcodes"
This reverts commit r288916 as it is currently causing a crasher in
Halide. Reproducer on llvm.org/PR31323. While it might be that halide is
generating invalid IR, llc shouldn't crash.

llvm-svn: 289194
2016-12-09 09:04:51 +00:00
Simon Pilgrim ba05d41095 [SelectionDAG] Add knownbits support for vector demandedelts in SMAX/SMIN/UMAX/UMIN opcodes
llvm-svn: 288926
2016-12-07 17:54:00 +00:00
Simon Pilgrim 967325b373 [SelectionDAG] Add knownbits support for EXTRACT_VECTOR_ELT opcodes
llvm-svn: 288916
2016-12-07 16:28:21 +00:00
Simon Pilgrim ff79f31328 [SelectionDAG] Removed old knownbits TODO comment. NFCI.
EXTRACT_VECTOR_ELT does support demanded elts if the element index is known and in range.

llvm-svn: 288913
2016-12-07 15:31:12 +00:00
Simon Pilgrim 1577b39f51 [SelectionDAG] We can ignore knownbits from an undef shuffle vector index if we don't actually demand that element
llvm-svn: 288839
2016-12-06 18:58:25 +00:00
Simon Pilgrim 29c17f3f58 Avoid repeated calls to Op.getOpcode(). NFCI.
llvm-svn: 288814
2016-12-06 14:50:09 +00:00
Matt Arsenault 92fede361f DAG: Fold out out of bounds insert_vector_elt
getNode already prevents formation of out of bounds constant
extract_vector_elts. Do the same for insert_vector_elt.

llvm-svn: 288603
2016-12-03 23:03:26 +00:00
John Brawn 150addb45c [DAGCombiner] Fix infinite loop in vector mul/shl combining
We have the following DAGCombiner transformations:
 (mul (shl X, c1), c2) -> (mul X, c2 << c1)
 (mul (shl X, C), Y) -> (shl (mul X, Y), C)
 (shl (mul x, c1), c2) -> (mul x, c1 << c2)
Usually the constant shift is optimised by SelectionDAG::getNode when it is
constructed, by SelectionDAG::FoldConstantArithmetic, but when we're dealing
with vectors and one of those vector constants contains an undef element
FoldConstantArithmetic does not fold and we enter an infinite loop.

Fix this by making FoldConstantArithmetic use getNode to decide how to fold each
vector element, the same as FoldConstantVectorArithmetic does, and rather than
adding the constant shift to the work list instead only apply the transformation
if it's already been folded into a constant, as if it's not we're going to loop
endlessly. Additionally add missing NoOpaques to one of those transformations,
which I noticed when writing the tests for this.

Differential Revision: https://reviews.llvm.org/D26605

llvm-svn: 287766
2016-11-23 16:05:51 +00:00
Simon Pilgrim 72e43570b7 [SelectionDAG] ComputeNumSignBits of TRUNCATE operations
Add basic ComputeNumSignBits support for TRUNCATE ops for cases where the source's number of sign bits overlaps with the truncated size.

Improves X86 SIGN_EXTEND_IN_REG vector cases which were needlessly sign extending boolean vector results.

Differential Revision: https://reviews.llvm.org/D26851

llvm-svn: 287635
2016-11-22 11:29:19 +00:00
Simon Pilgrim 49d7eda968 [SelectionDAG] Add ComputeNumSignBits support for CONCAT_VECTORS opcode
llvm-svn: 287541
2016-11-21 14:36:19 +00:00
Simon Pilgrim e40900dddd [SelectionDAG] Add knowbits support for CONCAT_VECTOR opcode
llvm-svn: 287387
2016-11-18 22:21:22 +00:00
Simon Pilgrim 807f9cf243 [SelectionDAG] Add support for vector demandedelts in BSWAP opcodes
llvm-svn: 286582
2016-11-11 11:51:29 +00:00
Simon Pilgrim 813721e98a [SelectionDAG] Add support for vector demandedelts in UREM/SREM opcodes
llvm-svn: 286578
2016-11-11 11:23:43 +00:00
Simon Pilgrim 0652227814 [SelectionDAG] Add support for vector demandedelts in UDIV opcodes
llvm-svn: 286576
2016-11-11 10:47:24 +00:00
Simon Pilgrim 38f0045cb0 [SelectionDAG] Add support for vector demandedelts in ADD/SUB opcodes
llvm-svn: 286516
2016-11-10 22:41:49 +00:00
Simon Pilgrim fe3a54371d [SelectionDAG] Add support for splatted vectors in SUB opcode
llvm-svn: 286509
2016-11-10 21:57:42 +00:00
Simon Pilgrim d67af68f06 [SelectionDAG] Add support for vector demandedelts in TRUNCATE opcodes
llvm-svn: 286481
2016-11-10 17:43:52 +00:00
Simon Pilgrim ee187fd6e7 [SelectionDAG] Add support for vector demandedelts in MUL opcodes
llvm-svn: 286471
2016-11-10 16:27:42 +00:00
Simon Pilgrim ca57e53ded [SelectionDAG] Add support for vector demandedelts in SRA opcodes
llvm-svn: 286461
2016-11-10 15:05:09 +00:00
Simon Pilgrim 3bf99c056a [SelectionDAG] Add support for vector demandedelts in SHL/SRL opcodes
llvm-svn: 286448
2016-11-10 13:52:42 +00:00
Simon Pilgrim 39df78e384 [SelectionDAG] Add support for vector demandedelts in XOR opcodes
llvm-svn: 286075
2016-11-06 16:49:19 +00:00
Simon Pilgrim dd4809a603 [SelectionDAG] Add support for vector demandedelts in OR opcodes
llvm-svn: 286071
2016-11-06 16:29:09 +00:00
Simon Pilgrim 93f2f7fb6c Use !operator to test if APInt is zero/non-zero. NFCI.
Avoids APInt construction and slower comparisons.

llvm-svn: 285822
2016-11-02 15:41:15 +00:00
Simon Pilgrim 75a697a17e [DAGCombiner] (REAPPLIED) Add vector demanded elements support to computeKnownBits
Currently computeKnownBits returns the common known zero/one bits for all elements of vector data, when we may only be interested in one/some of the elements.

This patch adds a DemandedElts argument that allows us to specify the elements we actually care about. The original computeKnownBits implementation calls with a DemandedElts demanding all elements to match current behaviour. Scalar types set this to 1.

The approach was found to be easier than trying to add a per-element known bits solution, for a similar usefulness given the combines where computeKnownBits is typically used.

I've only added support for a few opcodes so far (the ones that have proven straightforward to test), all others will default to demanding all elements but can be updated in due course.

DemandedElts support could similarly be added to computeKnownBitsForTargetNode in a future commit.

This looked like this had caused compile time regressions on some buildbots (and was reverted in rL285381), but appears to have just been a harmless bystander!

Differential Revision: https://reviews.llvm.org/D25691

llvm-svn: 285494
2016-10-29 11:29:39 +00:00
Simon Pilgrim d9189891fc [SelectionDAG] computeKnownBits - early-out if any BUILD_VECTOR element has no known bits
No need to check the remaining elements - no common known bits are available.

llvm-svn: 285399
2016-10-28 14:07:44 +00:00
Simon Pilgrim 8c043061e5 [SelectionDAG] Tidyup UDIV computeKnownBits implementation
No need to clear KnownOne2/KnownZero2 bits as the next call to computeKnownBits will overwrite them anyway

llvm-svn: 285398
2016-10-28 13:42:23 +00:00
Simon Pilgrim 755cef1ba8 [SelectionDAG] Increment computeKnownBits recursion depth for SMIN/SMAX/UMIN/UMAX like all other ops
llvm-svn: 285397
2016-10-28 13:13:16 +00:00