Commit Graph

2296 Commits

Author SHA1 Message Date
Craig Topper ad532be012 [SelectionDAG] Assert that operands to SelectionDAG::getNode are not DELETED_NODE to catch issues like PR49393 earlier.
I'm not sure this would catch all such issues, but it would catch some.

The problem for PR49393 was that we were holding a reference to a node that
wasn't connect edto the DAG across a function that could delete unused nodes. In
this particular case we managed to try to use the deleted node while it was in
the deleted state before its memory got recycled.

It could also happen that we delete the node, something allocates a new node
which recycles the memory. Then  we try to use the reference we were holding and
it is now a completely different node with different valid opcode. This patch
would not catch that.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D97969
2021-03-04 23:05:32 -08:00
Sanjay Patel 415c67ba4c [SDAG] allow partial undef vector constants with select->logic folds
This is an enhancement suggested in the original review/commit:
D97730 / 7fce3322a2
2021-03-02 14:29:15 -05:00
Fraser Cormack 6718fda6ad [CodeGen] Fix issues with subvector intrinsic index types
This patch addresses issues arising from the fact that the index type
used for subvector insertion/extraction is inconsistent between the
intrinsics and SDNodes. The intrinsic forms require i64 whereas the
SDNodes use the type returned by SelectionDAG::getVectorIdxTy.

Rather than update the intrinsic definitions to use an overloaded index
type, this patch fixes the issue by transforming the index to the
correct type as required. Any loss of index bits going from i64 to a
smaller type is unexpected, and will be caught by an assertion in
SelectionDAG::getVectorIdxConstant.

The patch also updates the documentation for INSERT_SUBVECTOR and adds
an assertion to its creation to bring it in line with EXTRACT_SUBVECTOR.
This necessitated changes to AArch64 which was using i64 for
EXTRACT_SUBVECTOR but i32 for INSERT_SUBVECTOR. Only one test changed
its codegen after updating the backend accordingly.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D97459
2021-03-01 10:28:21 +00:00
Simon Pilgrim aefe8f2f6c [DAG] Fold vXi1 multiplies -> and
This allows us to remove X86 custom lowering of vXi1 MUL, which helps simplify a load of mask math.

Mentioned in D97478 post review.
2021-02-26 11:46:12 +00:00
Simon Pilgrim 9490b9f14b [DAG] Move simplification of SADDSAT/SSUBSAT/UADDSAT/USUBSAT of vXi1 to getNode()
As discussed on D97276 we should be able to always do this in node creation, we don't need a combine.
2021-02-25 17:49:26 +00:00
David Sherwood 87dbcd8865 [CodeGen] Canonicalise adds/subs of i1 vectors using XOR
When calling SelectionDAG::getNode() to create an ADD or SUB
of two vectors with i1 element types we can canonicalise this
to use XOR instead, where 1+1 is treated as wrapping around
to 0 and 0-1 wraps to 1.

I've added the following tests for SVE targets:

  CodeGen/AArch64/sve-pred-arith.ll

and modified some X86 tests to reflect the much simpler codegen
required.

Differential Revision: https://reviews.llvm.org/D97276
2021-02-25 10:31:26 +00:00
Craig Topper 1a6c1ac686 [SelectionDAG][RISCV] Teach ComputeNumSignBits to handle SREM.
This also removes a pattern from RISCV that is no longer needed
since the sexti32 on the LHS of the srem in the pattern implies
the result is sign extended so the sign_extend_inreg should be
removed in DAG combine now.

Reviewed By: luismarques, RKSimon

Differential Revision: https://reviews.llvm.org/D97133
2021-02-21 11:13:36 -08:00
Simon Pilgrim 420420de57 [DAG] Avoid APInt copies by directly using the APInt reference from getAPIntValue. NFCI. 2021-02-16 13:50:34 +00:00
Simon Pilgrim dd879f7dc9 [DAG] Use APInt::extractBits instead of lshr().trunc(). NFCI.
Avoids so many APInt instances by directly using the APInt reference from getAPIntValue.
2021-02-16 13:50:33 +00:00
Kazu Hirata 7e75f6fc1d [SelectionDAG] Use range-based for loops (NFC) 2021-02-09 22:14:30 -08:00
Simon Pilgrim 86dabf4226 [DAG] SelectionDAG::isSplatValue - handle OR/XOR cases
Add OR/XOR to the basic binops that we support when checking for a splat vector value
2021-02-07 13:27:57 +00:00
Craig Topper 4553821815 [SelectionDAG] Prevent scalable vector warning from ComputeNumSignBits on extract_vector_elt on a scalable vector. 2021-02-01 23:42:03 -08:00
Fraser Cormack fde2466171 [SelectionDAG] Support scalable-vector splats in more cases
This patch adds support for scalable-vector splats in DAGCombiner's
`isConstantOrConstantVector` and `ISD::matchUnaryPredicate` functions,
which enable the SelectionDAG div/rem-by-constant optimizations for
scalable vector types.

It also fixes up one case where the UDIV optimization was generating a
SETCC without first consulting the target for its preferred SETCC result
type.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D94501
2021-01-25 10:58:15 +00:00
Jay Foad 868da2ea93 [SelectionDAG] Remove an early-out from computeKnownBits for smin/smax
Even if we know nothing about LHS, it can still be useful to know that
smax(LHS, RHS) >= RHS and smin(LHS, RHS) <= RHS.

Differential Revision: https://reviews.llvm.org/D87145
2021-01-14 18:15:17 +00:00
Jay Foad 517196e569 [Analysis,CodeGen] Make use of KnownBits::makeConstant. NFC.
Differential Revision: https://reviews.llvm.org/D94588
2021-01-14 14:02:43 +00:00
Kerry McLaughlin 2170e0ee60 [SVE][CodeGen] CTLZ, CTTZ & CTPOP operations (predicates)
Canonicalise the following operations in getNode() for predicate types:
 - CTLZ(Pred)  -> bitwise_NOT(Pred)
 - CTTZ(Pred)  -> bitwise_NOT(Pred)
 - CTPOP(Pred) -> Pred

Reviewed By: david-arm

Differential Revision: https://reviews.llvm.org/D94428
2021-01-13 12:24:54 +00:00
Craig Topper df74c001fa [DAGCombiner] Replace static helper function isConstantFPBuildVectorOrConstantFP with the identical version in SelectionDAG. NFC 2021-01-11 23:41:40 -08:00
Craig Topper f9ef3a6003 [SelectionDAG] Make isConstantIntBuildVectorOrConstantInt and isConstantFPBuildVectorOrConstantFP methods const. 2021-01-11 23:26:53 -08:00
Fraser Cormack 41d06095b0 [SelectionDAG] Teach isConstOrConstSplat about ISD::SPLAT_VECTOR
This improves llvm::isConstOrConstSplat by allowing it to analyze
ISD::SPLAT_VECTOR nodes, in order to allow more constant-folding of
operations using scalable vector types.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D94168
2021-01-09 20:54:34 +00:00
Fraser Cormack de373ef779 [SelectionDAG] Extend immAll(Ones|Zeros)V to handle ISD::SPLAT_VECTOR
The TableGen immAllOnesV and immAllZerosV helpers implicitly wrapped the
ISD::isBuildVectorAll(Ones|Zeros) helper functions. This was inhibiting
their use for targets such as RISC-V which use ISD::SPLAT_VECTOR. In
particular, RISC-V had to define its own 'vnot' fragment.

In order to extend the scope of these nodes to include support for
ISD::SPLAT_VECTOR, two new ISD predicate functions have been introduced:
ISD::isConstantSplatVectorAll(Ones|Zeros). These effectively supersede
the older "isBuildVector" predicates, which are now simple wrappers for
the new functions. They pass a defaulted boolean toggle which preserves
the old behaviour. It is hoped that in time all call-sites can be ported
to the "isConstantSplatVector" functions.

While the use of ISD::isBuildVectorAll(Ones|Zeros) has not changed, the
behaviour of the TableGen immAll(Ones|Zeros)V **has**. To test the new
functionality, the custom RISC-V TableGen fragment has been removed and
replaced with the built-in 'vnot'. To test their use as pattern-roots, two
splat patterns have been updated accordingly.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D94223
2021-01-09 17:05:31 +00:00
Simon Moll 611d3c63f3 [VP] ISD helper functions [VE] isel for vp_add, vp_and
This implements vp_add, vp_and for the VE target by lowering them to the
VVP_* layer. We also add helper functions for VP SDNodes (isVPSDNode,
getVPMaskIdx, getVPExplicitVectorLengthIdx).

Reviewed By: kaz7

Differential Revision: https://reviews.llvm.org/D93766
2021-01-08 14:29:45 +01:00
Fraser Cormack 9a1ac97d3a [CodeGen] Format SelectionDAG::getConstant methods (NFC) 2021-01-05 12:59:46 +00:00
Kazu Hirata 1e3ed09165 [CodeGen] Use llvm::append_range (NFC) 2020-12-28 19:55:16 -08:00
Simon Pilgrim cdb692ee0c [X86] Add X86ISD::SUBV_BROADCAST_LOAD and begin removing X86ISD::SUBV_BROADCAST (PR38969)
Subvector broadcasts are only load instructions, yet X86ISD::SUBV_BROADCAST treats them more generally, requiring a lot of fallback tablegen patterns.

This initial patch replaces constant vector lowering inside lowerBuildVectorAsBroadcast with direct X86ISD::SUBV_BROADCAST_LOAD loads which helps us merge a number of equivalent loads/broadcasts.

As well as general plumbing/analysis additions for SUBV_BROADCAST_LOAD, I needed to wrap SelectionDAG::makeEquivalentMemoryOrdering so it can handle result chains from non generic LoadSDNode nodes.

Later patches will continue to replace X86ISD::SUBV_BROADCAST usage.

Differential Revision: https://reviews.llvm.org/D92645
2020-12-17 10:25:25 +00:00
Justin Bogner e6a1187dd8 Limit the recursion depth of SelectionDAG::isSplatValue()
This method previously always recursively checked both the left-hand
side and right-hand side of binary operations for splatted (broadcast)
vector values to determine if the parent DAG node is a splat.

Like several other SelectionDAG methods, limit the recursion depth to
MaxRecursionDepth (6). This prevents stack overflow.
See also https://issuetracker.google.com/173785481

Patch by Nicolas Capens. Thanks!

Differential Revision: https://reviews.llvm.org/D92421
2020-12-09 10:35:07 -08:00
Kerry McLaughlin 4519ff4b6f [SVE][CodeGen] Add the ExtensionType flag to MGATHER
Adds the ExtensionType flag, which reflects the LoadExtType of a MaskedGatherSDNode.
Also updated SelectionDAGDumper::print_details so that details of the gather
load (is signed, is scaled & extension type) are printed.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D91084
2020-12-09 11:19:08 +00:00
Kerry McLaughlin f6dd32fd35 [SVE][CodeGen] Lower scalable masked gathers
Lowers the llvm.masked.gather intrinsics (scalar plus vector addressing mode only)

Changes in this patch:
- Add custom lowering for MGATHER, using getGatherVecOpcode() to choose the appropriate
  gather load opcode to use.
- Improve codegen with refineIndexType/refineUniformBase, added in D90942
- Tests added for gather loads with 32 & 64-bit scaled & unscaled offsets.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D91092
2020-12-07 12:20:41 +00:00
Simon Pilgrim 9cf4f493a7 [DAG] Move SelectionDAG implementation to KnownBits::setInReg(). NFCI. 2020-12-04 18:09:08 +00:00
Kazu Hirata 7a4af2a8e7 [SelectionDAG] Use is_contained (NFC) 2020-12-02 19:09:45 -08:00
Kerry McLaughlin 4bee3197f6 [SVE][CodeGen] Extend isConstantSplatValue to support ISD::SPLAT_VECTOR
Updated the affected scalable_of_scalable tests in sve-gep.ll, as isConstantSplatValue now returns true in DAGCombiner::visitMUL and folds `(mul x, 1) -> x`

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D91363
2020-11-26 11:19:40 +00:00
Kai Luo 8e6d92026c [DAG][PowerPC] Fix dropped `nsw` flag in `SimplifySetCC` by adding `doesNodeExist` helper
`SimplifySetCC` invokes `getNodeIfExists` without passing `Flags` argument and `getNodeIfExists` uses a default `SDNodeFlags` to intersect the original flags, as a consequence, flags like `nsw` is dropped. Added a new helper function `doesNodeExist` to check if a node exists without modifying its flags.

Reviewed By: #powerpc, nemanjai

Differential Revision: https://reviews.llvm.org/D89938
2020-11-25 04:39:03 +00:00
Hongtao Yu d0e42037bf [CSSPGO] MIR target-independent pseudo instruction for pseudo-probe intrinsic
This change introduces a MIR target-independent pseudo instruction corresponding to the IR intrinsic llvm.pseudoprobe for pseudo-probe block instrumentation. Please refer to https://reviews.llvm.org/D86193 for the whole story.

An `llvm.pseudoprobe` intrinsic call will be lowered into a target-independent operation named `PSEUDO_PROBE`. Given the following instrumented IR,

```
define internal void @foo2(i32 %x, void (i32)* %f) !dbg !4 {
bb0:
   %cmp = icmp eq i32 %x, 0
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 1)
   br i1 %cmp, label %bb1, label %bb2
bb1:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 2)
   br label %bb3
bb2:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 3)
   br label %bb3
bb3:
   call void @llvm.pseudoprobe(i64 837061429793323041, i64 4)
   ret void
}
```
the corresponding MIR is shown below. Note that block `bb3` is duplicated into `bb1` and `bb2` where its probe is duplicated too. This allows for an accurate execution count to be collected for `bb3`, which is basically the sum of the counts of `bb1` and `bb2`.

```
bb.0.bb0:
   frame-setup PUSH64r undef $rax, implicit-def $rsp, implicit $rsp
   TEST32rr killed renamable $edi, renamable $edi, implicit-def $eflags
   PSEUDO_PROBE 837061429793323041, 1, 0
   $edi = MOV32ri 1, debug-location !13; test.c:0
   JCC_1 %bb.1, 4, implicit $eflags

bb.2.bb2:
   PSEUDO_PROBE 837061429793323041, 3, 0
   PSEUDO_PROBE 837061429793323041, 4, 0
   $rax = frame-destroy POP64r implicit-def $rsp, implicit $rsp
   RETQ

bb.1.bb1:
   PSEUDO_PROBE 837061429793323041, 2, 0
   PSEUDO_PROBE 837061429793323041, 4, 0
   $rax = frame-destroy POP64r implicit-def $rsp, implicit $rsp
   RETQ
```

The target op PSEUDO_PROBE will be converted into a piece of binary data by the object emitter with no machine instructions generated. This is done in a different patch.

Reviewed By: wmi

Differential Revision: https://reviews.llvm.org/D86495
2020-11-20 10:52:43 -08:00
Kazu Hirata 2583d8eb08 [CodeGen] Use llvm::is_contained (NFC) 2020-11-19 22:07:56 -08:00
Simon Pilgrim 8996742741 [KnownBits] Add KnownBits::makeConstant helper. NFCI.
Helper for cases where we need to create a KnownBits from a (fully known) constant value.
2020-11-12 16:16:04 +00:00
Simon Pilgrim 1a62ca65c1 [KnownBits] Add KnownBits::commonBits helper. NFCI.
We have a frequent pattern where we're merging two KnownBits to get the common/shared bits, and I just fell for the gotcha where I tried to use the & operator to merge them........
2020-11-11 12:15:54 +00:00
Kerry McLaughlin 170947a5de [SVE][CodeGen] Lower scalable masked scatters
Lowers the llvm.masked.scatter intrinsics (scalar plus vector addressing mode only)

Changes included in this patch:
 - Custom lowering for MSCATTER, which chooses the appropriate scatter store opcode to use.
    Floating-point scatters are cast to integer, with patterns added to match FP reinterpret_casts.
 - Added the getCanonicalIndexType function to convert redundant addressing
   modes (e.g. scaling is redundant when accessing bytes)
 - Tests with 32 & 64-bit scaled & unscaled offsets

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D90941
2020-11-11 11:50:22 +00:00
Kerry McLaughlin ffbbfc76ca [SVE][CodeGen] Add the isTruncatingStore flag to MSCATTER
This patch adds the IsTruncatingStore flag to MaskedScatterSDNode, set by getMaskedScatter().
Updated SelectionDAGDumper::print_details for MaskedScatterSDNode to print
the details of masked scatters (is truncating, signed or scaled).

This is the first in a series of patches which adds support for scalable masked scatters

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D90939
2020-11-11 10:58:24 +00:00
Simon Pilgrim bf04e34383 [DAG] computeKnownBits - Replace ISD::SREM handling with KnownBits::srem to reduce code duplication 2020-11-05 17:12:58 +00:00
Simon Pilgrim e237d56b43 [KnownBits] Move ValueTracking/SelectionDAG UREM KnownBits handling to KnownBits::urem. NFCI.
Both these have the same implementation - so move them to a single KnownBits copy.

GlobalISel will be able to use this as well with minimal effort.
2020-11-05 14:30:59 +00:00
Simon Pilgrim 32bee18b84 [KnownBits] Move ValueTracking/SelectionDAG UDIV KnownBits handling to KnownBits::udiv. NFCI.
Both these have the same implementation - so move them to a single KnownBits copy.

GlobalISel will be able to use this as well with minimal effort.
2020-11-05 13:42:42 +00:00
Cameron McInally c126eb7529 [SelectionDAG] Add legalizations for VECREDUCE_SEQ_FMUL
Hook up legalizations for VECREDUCE_SEQ_FMUL. This is following up on the VECREDUCE_SEQ_FADD work from D90247.

Differential Revision: https://reviews.llvm.org/D90644
2020-11-04 14:20:31 -06:00
Kerry McLaughlin f2412d372d [SVE][CodeGen] Lower scalable integer vector reductions
This patch uses the existing LowerFixedLengthReductionToSVE function to also lower
scalable vector reductions. A separate function has been added to lower VECREDUCE_AND
& VECREDUCE_OR operations with predicate types using ptest.

Lowering scalable floating-point reductions will be addressed in a follow up patch,
for now these will hit the assertion added to expandVecReduce() in TargetLowering.

Reviewed By: paulwalker-arm

Differential Revision: https://reviews.llvm.org/D89382
2020-11-04 11:38:49 +00:00
Simon Pilgrim 825e517e34 [DAG] computeKnownBits - Replace ISD::MUL handling with the common KnownBits::computeForMul implementation 2020-11-04 11:32:08 +00:00
Simon Pilgrim e9b88c754a [DAG] computeKnownBits - Move ISD::SRA handling into KnownBits::ashr
As discussed on D90527, we should be trying to move shift handling functionality into KnownBits to avoid code duplication in SelectionDAG/GlobalISel/ValueTracking.
2020-11-03 18:09:33 +00:00
Simon Pilgrim cb798f040a [DAG] computeKnownBits - Move (most) ISD::SRL handling into KnownBits::lshr
As discussed on D90527, we should be be trying to move shift handling functionality into KnownBits to avoid code duplication in SelectionDAG/GlobalISel/ValueTracking.

The refactor to use the KnownBits fixed/min/max constant helpers allows us to hit a couple of cases that we were missing before.

We still need the getValidMinimumShiftAmountConstant case as KnownBits doesn't handle per-element vector cases.
2020-11-03 17:30:36 +00:00
Simon Pilgrim cab21d4fa8 [DAG] computeKnownBits - Move (most) ISD::SHL handling into KnownBits::shl
As discussed on D90527, we should be be trying to move shift handling functionality into KnownBits to avoid code duplication in SelectionDAG/GlobalISel/ValueTracking.

The refactor to use the KnownBits fixed/min/max constant helpers allows us to hit a couple of cases that we were missing before.

We still need the getValidMinimumShiftAmountConstant case as KnownBits doesn't handle per-element vector cases.
2020-11-03 14:22:28 +00:00
Cameron McInally dda1e74b58 [Legalize] Add legalizations for VECREDUCE_SEQ_FADD
Add Legalization support for VECREDUCE_SEQ_FADD, so that we don't need to depend on ExpandReductionsPass.

Differential Revision: https://reviews.llvm.org/D90247
2020-10-30 16:02:55 -05:00
Nikita Popov 6c2ad4cf87 [SDAG] Extract helper to determine neutral element (NFC)
Make the existing VECREDUCE based code more generic, but expressing
it in terms of the neutral value of the base opcode instead.
2020-10-29 22:05:06 +01:00
Nikita Popov 91bf172088 [SDAG] Extract helper to get vecreduce base opcode (NFC) 2020-10-29 20:22:22 +01:00
Simon Pilgrim ce356e1546 [DAG] Add BuildVectorSDNode::getRepeatedSequence helper to recognise multi-element splat patterns
Replace the X86 specific isSplatZeroExtended helper with a generic BuildVectorSDNode method.

I've just used this to simplify the X86ISD::BROADCASTM lowering so far (and remove isSplatZeroExtended), but we should be able to use this in more places to lower to complex broadcast patterns.

Differential Revision: https://reviews.llvm.org/D87930
2020-10-24 12:23:09 +01:00
Simon Pilgrim 88523f6f4b [DAG] getNode(ISD::EXTRACT_SUBVECTOR) Drop unnecessary N2C null check - we assert that this isn't null and have already used the pointer. NFCI.
Fixes cppcheck + null dereference warning.
2020-10-21 11:53:44 +01:00
David Sherwood 5b17b323a6 [SVE][CodeGen] Replace use of TypeSize comparison operator in CreateStackTemporary
We were previously relying upon the TypeSize comparison operators to
obtain the maximum size of two types, however use of such operators is
being deprecated in favour of making the caller aware that it could
be dealing with scalable vector types. I have changed the code to assert
that the two types have the same scalable property and thus we can
simply take the maximum of the known minimum sizes instead.

Differential Revision: https://reviews.llvm.org/D88563
2020-10-21 08:31:36 +01:00
Krzysztof Parzyszek 61eaa2e14a [SDAG] Remember to set UndefElts in isSplatValue for SPLAT_VECTOR 2020-10-10 19:42:24 -05:00
David Sherwood fa0293081d [SVE][CodeGen] Fix TypeSize/ElementCount related warnings in sve-split-store.ll
I have fixed up a number of warnings resulting from TypeSize -> uint64_t
casts and calling getVectorNumElements() on scalable vector types. I
think most of the changes are fairly trivial except for those in
DAGTypeLegalizer::SplitVecRes_MSTORE I've tried to ensure we create
the MachineMemoryOperands in a sensible way for scalable vectors.

I have added a CHECK line to the following test:

 CodeGen/AArch64/sve-split-store.ll

that ensures no new warnings are added.

Differential Revision: https://reviews.llvm.org/D86928
2020-10-05 19:27:00 +01:00
Sanjay Patel 2ccbf3dbd5 [SDAG] fold x * 0.0 at node creation time
In the motivating case from https://llvm.org/PR47517
we create a node that does not get constant folded
before getNegatedExpression is attempted from some
other node, and we crash.

By moving the fold into SelectionDAG::simplifyFPBinop(),
we get the constant fold sooner and avoid the problem.
2020-10-04 11:31:57 -04:00
Kerry McLaughlin fcf70e1e3b [SVE][CodeGen] Lower scalable fp_extend & fp_round operations
This patch adds FP_EXTEND_MERGE_PASSTHRU & FP_ROUND_MERGE_PASSTHRU
ISD nodes, used to lower scalable vector fp_extend/fp_round operations.
fp_round has an additional argument, the 'trunc' flag, which is an integer of zero or one.

This also fixes a warning introduced by the new tests added to sve-split-fcvt.ll,
resulting from an implicit TypeSize -> uint64_t cast in SplitVecOp_FP_ROUND.

Reviewed By: sdesmalen, paulwalker-arm

Differential Revision: https://reviews.llvm.org/D88321
2020-10-01 12:17:37 +01:00
Krzysztof Parzyszek db04bec5f1 [SDAG] Do not convert undef to 0 when folding CONCAT/BUILD_VECTOR
Differential Revision: https://reviews.llvm.org/D88273
2020-09-29 09:12:26 -05:00
Jay Foad d6b04f3937 [SDag] Refactor and simplify divergence calculation and checking. NFC. 2020-09-29 14:05:07 +01:00
Qiu Chaofan c0f8e4c06c [SelectionDAG] Add guard to automatically insert flags
This is like FastMathFlagGuard in IR. Since we use SDAG instance to get
values, it's with SelectionDAG. By creating a FlagInserter in current
scope, all values created by getNode will get the flags if no Flags
argument provided.

In this patch, I applied it to floating point operations folding part in
DAG combiner, and removed Flags passing to getNode to show its effect.
Other places in DAG combiner and other helper methods similar to getNode
also need this. They can be done in follow-up patches.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D87361
2020-09-26 13:57:52 +08:00
David Sherwood e077367a28 [SVE] Make EVT::getScalarSizeInBits and others consistent with Type::getScalarSizeInBits
An existing function Type::getScalarSizeInBits returns a uint64_t
instead of a TypeSize class because the caller is requesting a
scalar size, which cannot be scalable. This patch makes other
similar functions requesting a scalar size consistent with that,
thereby eliminating more than 1000 implicit TypeSize -> uint64_t
casts.

Differential revision: https://reviews.llvm.org/D87889
2020-09-23 09:20:08 +01:00
Simon Pilgrim d967aaa8fa [DAG] BuildVectorSDNode::getSplatValue - pull out repeated getNumOperands() calls. NFCI. 2020-09-18 16:10:23 +01:00
Craig Topper c193a689b4 [SelectionDAG] Use Align/MaybeAlign in calls to getLoad/getStore/getExtLoad/getTruncStore.
The versions that take 'unsigned' will be removed in the future.

I tried to use getOriginalAlign instead of getAlign in some
places. getAlign factors in the minimum alignment implied by
the offset in the pointer info. Since we're also passing the
pointer info we can use the original alignment.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D87592
2020-09-14 13:54:50 -07:00
Craig Topper 56b33391d3 [SelectionDAG] Move ISD:PARITY formation from DAGCombine to SimplifyDemandedBits.
Previously, we formed ISD::PARITY by looking for (and (ctpop X), 1)
but the AND might be separated from the ctpop. For example if the
parity result is multiplied by 2, we'll pull the AND through the
shift.

So to handle more cases, move to SimplifyDemandedBits where we
can handle more cases that result in only the LSB of the CTPOP
being used.
2020-09-13 21:04:13 -07:00
Simon Pilgrim d816499f95 [KnownBits] Move SelectionDAG::computeKnownBits ISD::ABS handling to KnownBits::abs
Move the ISD::ABS handling to a KnownBits::abs handler, to simplify future implementations in ValueTracking/GlobalISel.
2020-09-09 13:22:58 +01:00
Simon Wallis 79ea83e104 [SelectionDAG] memcpy expansion of const volatile struct ignores const zero
In getMemcpyLoadsAndStores(), a memcpy where the source is a zero constant is expanded to a MemOp::Set instead of a MemOp::Copy, even when the memcpy is volatile.
This is incorrect.

The fix is to add a check for volatile, and expand to MemOp::Copy in the volatile case.

Reviewed By: chill

Differential Revision: https://reviews.llvm.org/D87134
2020-09-07 13:22:09 +01:00
Jay Foad 5350e1b509 [KnownBits] Implement accurate unsigned and signed max and min
Use the new implementation in ValueTracking, SelectionDAG and
GlobalISel.

Differential Revision: https://reviews.llvm.org/D87034
2020-09-07 09:09:01 +01:00
David Sherwood 73a3d350a4 [SVE][CodeGen] Fix up warnings in sve-split-insert/extract tests
I have fixed up some more ElementCount/TypeSize related warnings in
the following tests:

  CodeGen/AArch64/sve-split-extract-elt.ll
  CodeGen/AArch64/sve-split-insert-elt.ll

In SelectionDAG::CreateStackTemporary we were relying upon the implicit
cast from TypeSize -> uint64_t when calling MachineFrameInfo::CreateStackObject.
I've fixed this by passing in the known minimum size instead, which I
believe is fine because the associated stack id indicates whether this
is a scalable object or not.

I've also fixed up a case in TargetLowering::SimplifyDemandedBits when
extracting a vector element from a scalable vector. The result is a scalar,
hence it wasn't caught at the start of the function. If the vector is
scalable we just bail out for now.

Differential Revision: https://reviews.llvm.org/D86431
2020-09-04 09:51:31 +01:00
Simon Pilgrim 1673a08044 SelectionDAG.h - remove unnecessary FunctionLoweringInfo.h include. NFCI.
Use forward declarations and move the include down to dependent files that actually use it.

This also exposes a number of implicit dependencies on KnownBits.h
2020-09-03 18:33:25 +01:00
Matt Arsenault 759482ddaa GlobalISel: Implement computeKnownBits for G_BSWAP and G_BITREVERSE 2020-09-01 12:49:57 -04:00
David Sherwood 9fbb113247 [SVE][CodeGen] Fix TypeSize/ElementCount related warnings in sve-split-load.ll
I have fixed up a number of warnings resulting from TypeSize -> uint64_t
casts and calling getVectorNumElements() on scalable vector types. I
think most of the changes are fairly trivial except for those in
DAGTypeLegalizer::SplitVecRes_MLOAD I've tried to ensure we create
the MachineMemoryOperands in a sensible way for scalable vectors.

I have added a CHECK line to the following test:

  CodeGen/AArch64/sve-split-load.ll

that ensures no new warnings are added.

Differential Revision: https://reviews.llvm.org/D86697
2020-09-01 07:47:59 +01:00
Paul Walker 73ac3c0ede [SVE] Lower scalable vector ISD::FNEG operations.
Also updates isConstOrConstSplatFP to allow the mul(A,-1) -> neg(A)
transformation when -1 is expressed as an ISD::SPLAT_VECTOR.

Differential Revision: https://reviews.llvm.org/D86415
2020-08-25 11:22:28 +01:00
David Sherwood 88bbd30736 [SVE][CodeGen] Fix issues with EXTRACT_SUBVECTOR when using scalable FP vectors
In this patch I have fixed two issues:

1. Our SVE tuple get/set intrinsics were using the wrong constant type
for the index passed to EXTRACT_SUBVECTOR. I have fixed this by using the
function SelectionDAG::getVectorIdxConstant to create the value. Also, I
have updated the documentation for EXTRACT_SUBVECTOR describing what type
the constant index should be and we now enforce this when creating the
node.
2. The AArch64 backend was missing the appropriate patterns for
extracting certain subvectors (nxv4f16 and nxv2f32) from legal SVE types.
I have added them as part of this patch.

The only way that I could find to test the new patterns was to use the
SVE tuple get intrinsics, although I realise it looks a bit unusual.
Tests added here:

  test/CodeGen/AArch64/sve-extract-subvector.ll

Differential Revision: https://reviews.llvm.org/D85516
2020-08-12 08:35:46 +01:00
Kerry McLaughlin 455ed56d48 [SVE][CodeGen] Legalisation of INSERT_VECTOR_ELT for scalable vectors
When the result type of insertelement needs to be split,
SplitVecRes_INSERT_VECTOR_ELT will try to store the vector to a
stack temporary, store the element at the location of the stack
temporary plus the index, and reload the Lo/Hi parts.

This patch does the following to ensure this works for scalable vectors:
 - Sets the StackID with getStackIDForScalableVectors() in CreateStackTemporary
 - Adds an IsScalable flag to getMemBasePlusOffset() and scales the
    offset by VScale when this is true
 - Ensures the immediate is clamped correctly by clampDynamicVectorIndex
    so that we don't try to use an out of range index

Reviewed By: david-arm

Differential Revision: https://reviews.llvm.org/D84874
2020-08-11 12:57:28 +01:00
Kerry McLaughlin 85c7e89f3b [CodeGen] Refactor getMemBasePlusOffset & getObjectPtrOffset to accept a TypeSize
Changes the Offset arguments to both functions from int64_t to TypeSize
& updates all uses of the functions to create the offset using TypeSize::Fixed()

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D85220
2020-08-11 12:17:10 +01:00
Simon Pilgrim 66a163f328 [DAG] GetDemandedBits - remove custom AND handling.
As mentioned on D85463, we should be using SimplifyMultipleUseDemandedBits (which is the default fallback).

The minor regression in illegal-bitfield-loadstore.ll will be addressed properly by D77804.
2020-08-07 12:55:47 +01:00
Simon Pilgrim fcefb53222 Remove unreachable break. NFC 2020-08-07 12:37:49 +01:00
Paul Walker 0d33a8ef5b [SVE] Lower scalable vector mul operations.
This allows us to remove extra patterns from AArch64SVEInstrInfo.td
because we can reuse those required for fixed length vectors.

Differential Revision: https://reviews.llvm.org/D85328
2020-08-06 11:15:35 +01:00
Eli Friedman 4a47f1c4ce [SelectionDAG][SVE] Support scalable vectors in getConstantFP()
Differential Revision: https://reviews.llvm.org/D85249
2020-08-04 15:32:43 -07:00
Matt Arsenault 57bd64ff84 Support addrspacecast initializers with isNoopAddrSpaceCast
Moves isNoopAddrSpaceCast to the TargetMachine. It logically belongs
with the DataLayout.
2020-07-31 10:42:43 -04:00
Simon Pilgrim b4b6e77454 [DAG] isSplatValue - add support for TRUNCATE/SIGN_EXTEND/ZERO_EXTEND
These are just pass-throughs to the source operand - we can't assume that ANY_EXTEND(splat) will still be a splat though.
2020-07-28 19:56:11 +01:00
Paul Walker 6e198aae1d [SelectionDAG] Prevent warnings when extracting fixed length vector from scalable.
ComputeNumSignBits and computeKnownBits both trigger "Scalable flag
may be dropped" warnings when a fixed length vector is extracted
from a scalable vector.  This patch assumes nothing about the
demanded elements thus matching the behaviour when extracting a
scalable vector from a scalable vector.

Differential Revision: https://reviews.llvm.org/D83642
2020-07-14 11:12:56 +00:00
David Sherwood 229dfb4728 [CodeGen] Replace calls to getVectorNumElements() in SelectionDAG::SplitVector
This patch replaces some invalid calls to getVectorNumElements() with calls
to getVectorMinNumElements() instead, since the code paths changed in this
patch work for both fixed and scalable vector types.

Fixes warnings in this test:

  sve-sext-zext.ll

Differential Revision: https://reviews.llvm.org/D83203
2020-07-10 08:11:30 +01:00
Lucas Prates fc39a9ca0e [CodeGen] Matching promoted type for 16-bit integer bitcasts from fp16 operand
Summary:
When legalizing a biscast operation from an fp16 operand to an i16 on a
target that requires both input and output types to be promoted to
32-bits, an assertion can fail when building the new node due to a
mismatch between the the operation's result size and the type specified to
the node.

This patches fix the issue by making sure the bit width of the types
match for the FP_TO_FP16 node, covering the difference with an extra
ANYEXTEND operation.

Reviewers: ostannard, efriedma, pirama, jmolloy, plotfi

Reviewed By: efriedma

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82552
2020-07-09 09:46:17 +01:00
Kerry McLaughlin 5e8084beba [SVE][CodeGen] Legalisation of unpredicated load instructions
Summary:
When splitting a load of a scalable type, the new address is
calculated in SplitVecRes_LOAD using a vscale and an add instruction.

This patch also adds a DAG combiner fold to visitADD for vscale:
 - Fold (add (vscale(C0)), (vscale(C1))) to (add (vscale(C0 + C1)))

Reviewers: sdesmalen, efriedma, david-arm

Reviewed By: david-arm

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82792
2020-07-07 11:05:03 +01:00
Simon Pilgrim 56a8a5c9fe [DAG] matchBinOpReduction - match subvector reduction patterns beyond a matched shufflevector reduction
Currently matchBinOpReduction only handles shufflevector reduction patterns, but in many cases these only occur in the final stages of a reduction, once we're down to legal vector widths.

Before this its likely that we are performing reductions using subvector extractions to repeatedly split the source vector in half and perform the binop on the halves.

Assuming we've found a non-partial reduction, this patch continues looking for subvector reductions as far as it can beyond the last shufflevector.

Fixes PR37890
2020-07-04 15:28:15 +01:00
Guillaume Chatelet c1cd61e02a [Alignment][NFC] Migrate SelectionDAGTargetInfo::EmitTargetCodeForMemcpy to Align
This patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82849
2020-06-30 13:12:31 +00:00
Guillaume Chatelet 306d7c6929 [Alignment][NFC] Migrate SelectionDAGTargetInfo::EmitTargetCodeForMemmove to Align
This patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82850
2020-06-30 12:46:59 +00:00
Guillaume Chatelet 6a6af30d43 [Alignment][NFC] Migrate SelectionDAGTargetInfo::EmitTargetCodeForMemset to Align
This patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82851
2020-06-30 12:46:26 +00:00
David Sherwood c02332a693 [CodeGen] Fix warning in getNode for EXTRACT_SUBVECTOR
Fix a warning in getNode() when extracting a subvector from a
concat vector. We can simply replace the call to getVectorNumElements
with getVectorMinNumElements as this follows the defined behaviour
for EXTRACT_SUBVECTOR.

Differential Revision: https://reviews.llvm.org/D82746
2020-06-30 08:11:41 +01:00
Michael Liao b1360caa82 [SDAG] Add new AssertAlign ISD node.
Summary:
- AssertAlign node records the guaranteed alignment on its source node,
  where these alignments are retrieved from alignment attributes in LLVM
  IR. These tracked alignments could help DAG combining and lowering
  generating efficient code.
- In this patch, the basic support of AssertAlign node is added. So far,
  we only generate AssertAlign nodes on return values from intrinsic
  calls.
- Addressing selection in AMDGPU is revised accordingly to capture the
  new (base + offset) patterns.

Reviewers: arsenm, bogner

Subscribers: jvesely, wdng, nhaehnle, tpr, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81711
2020-06-23 00:51:11 -04:00
David Sherwood 9e811b0d93 [CodeGen] Fix ComputeNumSignBits for scalable vectors
When trying to calculate the number of sign bits for scalable vectors
we should just bail out for now and pretend we know nothing.

Differential Revision: https://reviews.llvm.org/D81093
2020-06-19 07:58:42 +01:00
David Sherwood 65912a9768 [CodeGen] Fix warnings in foldCONCAT_VECTORS
Instead of asserting the number of elements is the same, we should be
comparing the element counts instead. In addition, when looking at
concats of extract_subvectors it's fine to use getVectorMinNumElements()
for scalable vectors.

I discovered these warnings when compiling the structured loads tests in
this file:

  test/CodeGen/AArch64/sve-intrinsics-loads.ll

Differential Revision: https://reviews.llvm.org/D81936
2020-06-18 09:29:37 +01:00
Aaron Smith 7e01675ea5 [SelectionDAG] Add MVT::bf16 to getConstantFP()
Summary:
This was probably overlooked in recent bfloat patches.
Needed to handle bf16 constants in SelectionDAG.

  ConstantFP:bf16<APFloat(0)>

Reviewers: stuij

Reviewed By: stuij

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81779
2020-06-16 15:10:05 -07:00
David Sherwood bd97342a0c [CodeGen] Let computeKnownBits do something sensible for scalable vectors
Until we have a real need for computing known bits for scalable
vectors I have simply changed the code to bail out for now and
pretend we know nothing. I've also fixed up some simple callers of
computeKnownBits too.

Differential Revision: https://reviews.llvm.org/D80437
2020-06-11 08:17:11 +01:00
Guillaume Chatelet e26ed6bdae Fix unused variable warning 2020-06-09 08:56:05 +00:00
David Sherwood cc8872400c [CodeGen] Ensure callers of CreateStackTemporary use sensible alignments
In two instances of CreateStackTemporary we are sometimes promoting
alignments beyond the stack alignment. I have introduced a new function
called getReducedAlign that will return the alignment for the broken
down parts of illegal vector types. For example, on NEON a <32 x i8>
type is made up of two <16 x i8> types - in this case the sensible
alignment is 16 bytes, not 32.

In the legalization code wherever we create stack temporaries I have
started using the reduced alignments instead for illegal vector types.

I added a test to

  CodeGen/AArch64/build-one-lane.ll

that tries to insert an element into an illegal fixed vector type
that involves creating a temporary stack object.

Differential Revision: https://reviews.llvm.org/D80370
2020-06-09 08:10:17 +01:00
Matt Arsenault af867b7850 DAG: Change computeKnownBitsForFrameIndex to be usable by GISel
This wasn't getting much value from the DAG or depth arguments, since
it's only called on the frame index root nodes. FrameIndexes can also
only return a scalar value, so it also didn't need DemandedElts.
2020-06-04 10:50:26 -04:00
Simon Pilgrim c438b257f1 [DAG] GetDemandedBits - don't bother asserting for a non-null cast<> result. NFC.
cast<> will assert on failure anyhow.

This lets us fold the cast<> with the getAPIntValue() that uses it.
2020-06-03 12:43:07 +01:00
Matt Arsenault 836c7dcf12 DAG: Fix getNode dropping flags if there's a glue output
The AMDGPU non-strict fdiv lowering needs to introduce an FP mode
switch in some cases, and has custom nodes to provide chain/glue for
the intermediate FP operations. We need to propagate nofpexcept here,
but getNode was dropping the flags.

Adding nofpexcept in the AMDGPU custom lowering is left to a future
patch.

Also fix a second case where flags were dropped, but in this case it
seems it just didn't handle this number of operands.

Test will be included in future AMDGPU patch.
2020-06-01 13:48:02 -04:00
Simon Pilgrim 9d0bfcec83 [SelectionDAG] ComputeNumSignBits - use Valid Min/Max shift amount helpers directly. NFCI.
We are calling getValidShiftAmountConstant first followed by getValidMinimumShiftAmountConstant/getValidMaximumShiftAmountConstant if that failed. But both are used in the same way in ComputeNumSignBits and the Min/Max variants call getValidShiftAmountConstant internally anyhow.
2020-05-30 14:02:14 +01:00
Simon Pilgrim 81b50a7823 [SelectionDAG] Remove repeated getOperand() call. NFC. 2020-05-30 10:21:36 +01:00
Paul Walker 92f3d29af0 [SelectionDAG] Update getNode asserts for EXTRACT/INSERT_SUBVECTOR.
Summary:
The description of EXTACT_SUBVECTOR and INSERT_SUBVECTOR has been
changed to accommodate scalable vectors (see ISDOpcodes.h). This
patch updates the asserts used to verify these requirements when
using SelectionDAG's getNode interface.

This patch introduces the MVT function getVectorMinNumElements
that can be used against fixed-length and scalable vectors when
only the known minimum vector length is required.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80709
2020-05-29 11:02:18 +00:00
David Sherwood 4265f1d23c [CodeGen] Fix warnings in getZeroExtendInReg
We should be using getVectorElementCount() to assert that two types
have the same numbers of elements. I encountered the warnings while
compiling this test:

  CodeGen/AArch64/sve-intrinsics-ld1.ll

Differential Revision: https://reviews.llvm.org/D80616
2020-05-29 11:51:07 +01:00
David Sherwood b147b88c84 [CodeGen] Add support for extracting elements of scalable vectors
I have tried to ensure that SelectionDAG and DAGCombiner do
sensible things for scalable vectors, and added support for a
limited number of simple folds. Codegen support for the vector
extract patterns have also been added to the AArch64 backend.

New vector extract tests have been added here:

  CodeGen/AArch64/sve-extract-element.ll

and I have also added new folds using inserts and extracts here:

  CodeGen/AArch64/sve-insert-element.ll

Differential Revision: https://reviews.llvm.org/D80208
2020-05-29 07:49:43 +01:00
Serge Pavlov 4d20e31f73 [FPEnv] Intrinsic llvm.roundeven
This intrinsic implements IEEE-754 operation roundToIntegralTiesToEven,
and performs rounding to the nearest integer value, rounding halfway
cases to even. The intrinsic represents the missed case of IEEE-754
rounding operations and now llvm provides full support of the rounding
operations defined by the standard.

Differential Revision: https://reviews.llvm.org/D75670
2020-05-26 19:24:58 +07:00
Arthur Eubanks 8a88755610 Reland [X86] Codegen for preallocated
See https://reviews.llvm.org/D74651 for the preallocated IR constructs
and LangRef changes.

In X86TargetLowering::LowerCall(), if a call is preallocated, record
each argument's offset from the stack pointer and the total stack
adjustment. Associate the call Value with an integer index. Store the
info in X86MachineFunctionInfo with the integer index as the key.

This adds two new target independent ISDOpcodes and two new target
dependent Opcodes corresponding to @llvm.call.preallocated.{setup,arg}.

The setup ISelDAG node takes in a chain and outputs a chain and a
SrcValue of the preallocated call Value. It is lowered to a target
dependent node with the SrcValue replaced with the integer index key by
looking in X86MachineFunctionInfo. In
X86TargetLowering::EmitInstrWithCustomInserter() this is lowered to an
%esp adjustment, the exact amount determined by looking in
X86MachineFunctionInfo with the integer index key.

The arg ISelDAG node takes in a chain, a SrcValue of the preallocated
call Value, and the arg index int constant. It produces a chain and the
pointer fo the arg. It is lowered to a target dependent node with the
SrcValue replaced with the integer index key by looking in
X86MachineFunctionInfo. In
X86TargetLowering::EmitInstrWithCustomInserter() this is lowered to a
lea of the stack pointer plus an offset determined by looking in
X86MachineFunctionInfo with the integer index key.

Force any function containing a preallocated call to use the frame
pointer.

Does not yet handle a setup without a call, or a conditional call.
Does not yet handle musttail. That requires a LangRef change first.

Tried to look at all references to inalloca and see if they apply to
preallocated. I've made preallocated versions of tests testing inalloca
whenever possible and when they make sense (e.g. not alloca related,
inalloca edge cases).

Aside from the tests added here, I checked that this codegen produces
correct code for something like

```
struct A {
        A();
        A(A&&);
        ~A();
};

void bar() {
        foo(foo(foo(foo(foo(A(), 4), 5), 6), 7), 8);
}
```

by replacing the inalloca version of the .ll file with the appropriate
preallocated code. Running the executable produces the same results as
using the current inalloca implementation.

Reverted due to unexpectedly passing tests, added REQUIRES: asserts for reland.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77689
2020-05-20 11:25:44 -07:00
Arthur Eubanks b8cbff51d3 Revert "[X86] Codegen for preallocated"
This reverts commit 810567dc69.

Some tests are unexpectedly passing
2020-05-20 10:04:55 -07:00
Arthur Eubanks 810567dc69 [X86] Codegen for preallocated
See https://reviews.llvm.org/D74651 for the preallocated IR constructs
and LangRef changes.

In X86TargetLowering::LowerCall(), if a call is preallocated, record
each argument's offset from the stack pointer and the total stack
adjustment. Associate the call Value with an integer index. Store the
info in X86MachineFunctionInfo with the integer index as the key.

This adds two new target independent ISDOpcodes and two new target
dependent Opcodes corresponding to @llvm.call.preallocated.{setup,arg}.

The setup ISelDAG node takes in a chain and outputs a chain and a
SrcValue of the preallocated call Value. It is lowered to a target
dependent node with the SrcValue replaced with the integer index key by
looking in X86MachineFunctionInfo. In
X86TargetLowering::EmitInstrWithCustomInserter() this is lowered to an
%esp adjustment, the exact amount determined by looking in
X86MachineFunctionInfo with the integer index key.

The arg ISelDAG node takes in a chain, a SrcValue of the preallocated
call Value, and the arg index int constant. It produces a chain and the
pointer fo the arg. It is lowered to a target dependent node with the
SrcValue replaced with the integer index key by looking in
X86MachineFunctionInfo. In
X86TargetLowering::EmitInstrWithCustomInserter() this is lowered to a
lea of the stack pointer plus an offset determined by looking in
X86MachineFunctionInfo with the integer index key.

Force any function containing a preallocated call to use the frame
pointer.

Does not yet handle a setup without a call, or a conditional call.
Does not yet handle musttail. That requires a LangRef change first.

Tried to look at all references to inalloca and see if they apply to
preallocated. I've made preallocated versions of tests testing inalloca
whenever possible and when they make sense (e.g. not alloca related,
inalloca edge cases).

Aside from the tests added here, I checked that this codegen produces
correct code for something like

```
struct A {
        A();
        A(A&&);
        ~A();
};

void bar() {
        foo(foo(foo(foo(foo(A(), 4), 5), 6), 7), 8);
}
```

by replacing the inalloca version of the .ll file with the appropriate
preallocated code. Running the executable produces the same results as
using the current inalloca implementation.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77689
2020-05-20 09:20:38 -07:00
David Sherwood fb1c55b57d [CodeGen] Fix FoldConstantVectorArithmetic for scalable vectors
For now I have changed FoldConstantVectorArithmetic to return early
if we encounter a scalable vector, since the subsequent code assumes
you can perform lane-wise constant folds. However, in future work we
should be able to extend this to look at splats of a constant value
and fold those if possible. I have also added the same code to
FoldConstantArithmetic, since that deals with vectors too.

The warnings I fixed in this patch were being generated by this
existing test:

  CodeGen/AArch64/sve-int-arith.ll

Differential Revision: https://reviews.llvm.org/D79421
2020-05-15 14:58:44 +01:00
David Sherwood 8ce4a8f6df [CodeGen] Refactor CreateStackTemporary
I've created a new variant of CreateStackTemporary that takes
TypeSize and Align arguments, and made the older instances of
CreateStackTemporary call this new function. This refactoring is
in preparation for more patches in this area related to scalable
vectors and improving the alignment calculations.

Differential Revision: https://reviews.llvm.org/D79933
2020-05-15 07:29:13 +01:00
Simon Pilgrim 80715b7124 SelectionDAG.cpp - remove non-constant EXTRACT_SUBVECTOR/INSERT_SUBVECTOR handling. NFC.
Now that D79814 has landed, we can assume that subvector ops use constant, in-range indices.
2020-05-14 13:23:00 +01:00
Eric Christopher bfa200ebcf Remove an unused variable. 2020-05-13 15:13:02 -07:00
Eli Friedman ed428c429e [SelectionDAG] Require constant index for INSERT/EXTRACT_SUBVECTOR.
It sounds like an interesting idea in theory, but nothing is actually
taking advantage of it, and specifying/implementing the edge cases is
painful. So just forbid it.

Differential Revision: https://reviews.llvm.org/D79814
2020-05-13 13:08:59 -07:00
David Sherwood 42c7a6d52b [CodeGen] Fix incorrect uses of getVectorNumElements()
I have fixed up some places in SelectionDAG::getNode() where we
used to assert that the number of vector elements for two types
are the same. I have changed such cases to assert that the
element counts are the same instead. I've added new tests that
exercise the code paths for all the truncations. All the extend
operations are covered by this existing test:

  CodeGen/AArch64/sve-sext-zext.ll

For the ISD::SETCC case I fixed this code path is exercised by
these existing tests:

  CodeGen/AArch64/sve-fcmp.ll
  CodeGen/AArch64/sve-intrinsics-int-compares-with-imm.ll

Differential Revision: https://reviews.llvm.org/D79399
2020-05-12 07:50:37 +01:00
Craig Topper d1119980e5 [SelectionDAG] Use Align/MaybeAlign for ConstantPoolSDNode.
This patch stores the alignment for ConstantPoolSDNode as an
Align and updates the getConstantPool interface to take a MaybeAlign.

Removing getAlignment() will be done as a follow up.

Differential Revision: https://reviews.llvm.org/D79436
2020-05-08 16:04:11 -07:00
David Sherwood cd3a54c55a [CodeGen] Fix warnings due to SelectionDAG::getSplatSourceVector
Summary:
I have fixed several places in getSplatSourceVector and isSplatValue
to work correctly with scalable vectors. I added new support for
the ISD::SPLAT_VECTOR DAG node as one of the obvious cases we can
support with scalable vectors. In other places I have tried to do
the sensible thing, such as bail out for vector types we don't yet
support or don't intend to support.

It's not possible to add IR test cases to cover these changes, since
they are currently only ever exercised on certain targets, e.g.
only X86 targets use the result of getSplatSourceVector. I've
assumed that X86 tests already exist to test these code paths for
fixed vectors. However, I have added some AArch64 unit tests that
test the specific functions I have changed.

Differential revision: https://reviews.llvm.org/D79083
2020-05-05 08:45:41 +01:00
David Sherwood 058cd8c5be [CodeGen] Add support for inserting elements into scalable vectors
Summary:
This patch tries to ensure that we do something sensible when
generating code for the ISD::INSERT_VECTOR_ELT DAG node when operating
on scalable vectors. Previously we always returned 'undef' when
inserting an element into an out-of-bounds lane index, whereas now
we only do this for fixed length vectors. For scalable vectors it
is assumed that the backend will do the right thing in the same way
that we have to deal with variable lane indices.

In this patch I have permitted a few basic combinations for scalable
vector types where it makes sense, but in general avoided most cases
for now as they currently require the use of BUILD_VECTOR nodes.

This patch includes tests for all scalable vector types when inserting
into lane 0, but I've only included one or two vector types for other
cases such as variable lane inserts.

Differential Revision: https://reviews.llvm.org/D78992
2020-04-30 11:14:04 +01:00
David Sherwood 096b25a8d8 [CodeGen] Use SPLAT_VECTOR for zeroinitialiser with scalable types
Summary:
When generating code for the LLVM IR zeroinitialiser operation, if
the vector type is scalable we should be using SPLAT_VECTOR instead
of BUILD_VECTOR.

Differential Revision: https://reviews.llvm.org/D78636
2020-04-27 15:57:59 +01:00
aartbik 907871d9ad [llvm] [CodeGen] Fixed vector halving bug for masked load
Summary:
Given a VL=14 that is enveloped by a proper VL=16, splitting the
masked load using the enveloping halving VL=8/8 should yields
should eventually yield V=8/5. This fixes various assert failures
in getHalfNumVectorElementsVT() and IncrementMemoryAddress().

Note, I suspect similar fixes will be needed for other masked
operations, but for now I send out a fix for masked load only.

Bugzilla issue 45563
https://bugs.llvm.org/show_bug.cgi?id=45563

Reviewers: craig.topper, mehdi_amini, nicolasvasilache

Reviewed By: craig.topper

Subscribers: hiraditya, dmgreen, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78608
2020-04-23 15:12:44 -07:00
Jay Foad c63aed890e [KnownBits] Move AND, OR and XOR logic into KnownBits
Summary:
There are at least three clients for KnownBits calculations:
ValueTracking, SelectionDAG and GlobalISel. To reduce duplication the
common logic should be moved out of these clients and into KnownBits
itself.

This patch does this for AND, OR and XOR calculations by implementing
and using appropriate operator overloads KnownBits::operator& etc.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74060
2020-04-09 10:10:37 +01:00
Craig Topper c41685b16f [SelectionDAG] Make getZeroExtendInReg take a vector VT if the operand VT is a vector.
This removes a call to getScalarType from a bunch of call sites.
It also makes the behavior consistent with SIGN_EXTEND_INREG.

Differential Revision: https://reviews.llvm.org/D77631
2020-04-07 11:34:08 -07:00
Simon Pilgrim b02c7a8152 Fix "result of 32-bit shift implicitly converted to 64 bits" MSVC warning. NFCI.
The shift of 1 by an amount that is never more than 31 means that the warning is a false positive but is safe and fixes Werror builds.
2020-04-02 12:02:04 +01:00
Guillaume Chatelet 3a78f44daf [Alignment][NFC] Convert SelectionDAG::InferPtrAlignment to MaybeAlign
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77212
2020-04-01 13:22:11 +00:00
Guillaume Chatelet c7468c1696 [Alignment][NFC] Use Align in SelectionDAG::getMemIntrinsicNode
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jholewinski, nemanjai, hiraditya, kbarton, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77149
2020-04-01 09:32:05 +00:00
Guillaume Chatelet 998118c3d3 [Alignment][NFC] Deprecate MachineMemOperand::getMachineMemOperand version that takes an untyped alignement.
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: hiraditya, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77138
2020-03-31 16:05:31 +00:00
Craig Topper 2a07221cf3 [SelectionDAG] Add an assert that the input VT and output VT for ISD::FREEZE are the same.
Differential Revision: https://reviews.llvm.org/D77092
2020-03-30 23:21:58 -07:00
Guillaume Chatelet bdf77209b9 [Alignment][NFC] Use Align version of getMachineMemOperand
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jyknight, sdardis, nemanjai, hiraditya, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, jfb, PkmX, jocewei, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77059
2020-03-30 15:46:27 +00:00
Guillaume Chatelet 01ba2ad9ef [Alignment][NFC] Provide tightened up functions in SelectionDAG, MachineFunction and MachineMemOperand
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: hiraditya, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77046
2020-03-30 13:03:27 +00:00
Juneyoung Lee 1bcc500b48 [DAGCombine] Add basic optimizations for FREEZE in SelDag
Summary: This patch is the first effort to adding basic optimizations for FREEZE in SelDag.

Reviewers: spatel, lebedev.ri

Reviewed By: spatel

Subscribers: xbolva00, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D76707
2020-03-27 12:20:39 +09:00
Jay Foad 7cdbf1ed4b Make use of APInt::countLeadingOnes. NFC. 2020-03-23 09:08:20 +00:00
Craig Topper 498b53890d [SelectionDAGBuilder][FPEnv] Take into account SelectionDAG continuous CSE when setting the nofpexcept flag for constrained intrinsics
SelectionDAG CSEs nodes based on their result type and operands, but not their flags. The flags are expected to be intersected when they are CSEd. In SelectionDAGBuilder, for FP nodes we manage both the fast math flags and the nofpexcept flag after the nodes have already been CSEd when they were created with getNode. The management of the fastmath flags before the constrained nodes prevents the nofpexcept management from working correctly.

This commit moves the FMF handling for constrained intrinsics into their visitor and disables the common FMF handling for these nodes.

Differential Revision: https://reviews.llvm.org/D75224
2020-03-18 13:37:17 -07:00
Thomas Lively 4e589e6c26 [WebAssembly] Fix SIMD shift unrolling to avoid assertion failure
Summary:
Using the default DAG.UnrollVectorOp on v16i8 and v8i16 vectors
results in i8 or i16 nodes being inserted into the SelectionDAG. Since
those are illegal types, this causes a legalization assertion failure
for some code patterns, as uncovered by PR45178. This change unrolls
shifts manually to avoid this issue by adding and using a new optional
EVT argument to DAG.ExtractVectorElements to control the type of the
extract_element nodes.

Reviewers: aheejin, dschuff

Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, zzheng, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D76043
2020-03-12 12:20:14 -07:00
Andrzej Warzynski 46b9f14d71 [AArch64][SVE] Add intrinsics for non-temporal scatters/gathers
Summary:
This patch adds the following intrinsics for non-temporal gather loads
and scatter stores:
  * aarch64_sve_ldnt1_gather_index
  * aarch64_sve_stnt1_scatter_index
These intrinsics implement the "scalar + vector of indices" addressing
mode.

As opposed to regular and first-faulting gathers/scatters, there's no
instruction that would take indices and then scale them. Instead, the
indices for non-temporal gathers/scatters are scaled before the
intrinsics are lowered to `ldnt1` instructions.

The new ISD nodes, GLDNT1_INDEX and SSTNT1_INDEX, are only used as
placeholders so that we can easily identify the cases implemented in
this patch in performGatherLoadCombine and performScatterStoreCombined.
Once encountered, they are replaced with:
  * GLDNT1_INDEX -> SPLAT_VECTOR + SHL + GLDNT1
  * SSTNT1_INDEX -> SPLAT_VECTOR + SHL + SSTNT1

The patterns for lowering ISD::SHL for scalable vectors (required by
this patch) were missing, so these are added too.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D75601
2020-03-12 13:55:56 +00:00
Sanjay Patel 29a2b20ab3 [SDAG] simplify FP binops to undef
As discussed in the commit thread for rGa253a2a and D73978, we can do more undef folding for FP ops.
The nnan and ninf fast-math-flags specify that if an operand is the disallowed value, the result is
poison, so we can produce an undef result.

But this doesn't work as expected (the undef operand cases remain) because of a Flags propagation
problem in SelectionDAGBuilder.

I've added DAGCombiner calls to enable these for the other cases because we've shown in other
patches that (because of the limited way that SDAG iterates), it is possible to miss simplifications
like this if they are done only at node creation time.

Several potential follow-ups to expand on this patch are possible.

Differential Revision: https://reviews.llvm.org/D75576
2020-03-04 10:42:16 -05:00
Simon Pilgrim 53b597cfa2 [SelectionDAG] Merge constant SDNode arithmetic into foldConstantArithmetic
This is the second patch as part of https://bugs.llvm.org/show_bug.cgi?id=36544

Merging in the ConstantSDNode variant of FoldConstantArithmetic. After this, I will begin merging in FoldConstantVectorArithmetic

I've ensured this patch can build & pass all lit tests in Windows and Linux environments.

Patch by @justice_adams (Justice Adams)

Differential Revision: https://reviews.llvm.org/D74881
2020-02-24 18:54:22 +00:00
Craig Topper 3a6bb32bd2 [SelectionDAG] Remove ISD::LIFETIME_START/LIFETIME_END from assert in getMemIntrinsicNode.
These appear to have their own SDNode type and shouldn't use
MemIntrinsicSDNode.
2020-02-23 22:32:36 -08:00
Sanjay Patel a253a2a793 [SDAG] fold fsub -0.0, undef to undef rather than NaN
A question about this behavior came up on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2020-February/139003.html
...and as part of backend improvements in D73978.

We decided not to implement a more general change that would have
folded any FP binop with nearly arbitrary constant + undef operand
to undef because that is not theoretically correct (even if it is
practically correct).

This is the SDAG-equivalent to the IR change in D74713.
2020-02-23 11:36:53 -05:00
Simon Pilgrim a1585aec6f [SelectionDAG] Expose the "getValidShiftAmount" helpers available. NFCI.
These are going to be useful in TargetLowering::SimplifyDemandedBits, so expose these helpers outside of SelectionDAG.cpp

Also add an getValidShiftAmountConstant early-out to getValidMinimumShiftAmountConstant/getValidMaximumShiftAmountConstant so we can use them for scalar cases as well.
2020-02-17 16:28:46 +00:00
Jay Foad 32aac25637 [KnownBits] Introduce anyext instead of passing a flag into zext
Summary:
This was a very odd API, where you had to pass a flag into a zext
function to say whether the extended bits really were zero or not. All
callers passed in a literal true or false.

I think it's much clearer to make the function name reflect the
operation being performed on the value we're tracking (rather than on
the KnownBits Zero and One fields), so zext means the value is being
zero extended and new function anyext means the value is being extended
with unknown bits.

NFC.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74482
2020-02-12 19:06:53 +00:00
Guillaume Chatelet 333f2ad8b8 [Alignment][NFC] Use Align for getMemcpy/Memmove/Memset
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: arsenm, dschuff, jyknight, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Jim, lenary, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73885
2020-02-03 17:13:19 +01:00
Guillaume Chatelet fc19465965 [Alignment][NFC] Use Align for code creating MemOp
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73874
2020-02-03 14:10:30 +01:00
Guillaume Chatelet 75d9994a51 Fix broken invariant
Summary:
A Copy with a source that is zeros is the same as a Set of zeros.
This fixes the invariant that SrcAlign should always be non-null.

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73791
2020-02-03 11:01:05 +01:00
Guillaume Chatelet 3c89b75f23 [NFC] Introduce a type to model memory operation
Summary: This is a first step before changing the types to llvm::Align and introduce functions to ease client code.

Reviewers: courbet

Subscribers: arsenm, sdardis, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, jrtc27, atanasyan, jsji, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73785
2020-01-31 17:29:01 +01:00
Wang, Pengfei 17b8f96d65 [FPEnv] Divide macro INSTRUCTION into INSTRUCTION and DAG_INSTRUCTION,
and macro FUNCTION likewise. NFCI.

Some functions like fmuladd don't really have a node, we should divide
the declaration form those have node to avoid introducing fake nodes.

Differential Revision: https://reviews.llvm.org/D72871
2020-01-27 10:38:05 +08:00
Simon Pilgrim 3daa71ee00 [SelectionDAG] ComputeNumSignBits - add DemandedElts support for MIN/MAX ops 2020-01-25 20:21:14 +00:00
Simon Pilgrim 3f8916b2e8 [SelectionDAG] ComputeNumSignBits - add support for rotate non-uniform vector amounts 2020-01-25 19:15:05 +00:00
Simon Pilgrim e3c26a9d1b [SelectionDAG] ComputeNumSignBits - add support for rotate uniform vector amounts 2020-01-25 18:55:47 +00:00
@justice_adams (Justice Adams) daee63f974 [SelectionDag] Updated FoldConstantArithmetic method signature in preparation for merge with FoldConstantVectorArithmetic
Updated FoldConstantArithmetic method signature to match that of
FoldConstantVectorArithmetic in preparation for merging the two
functions together

https://bugs.llvm.org/show_bug.cgi?id=36544

This is the first step in combining the various
FoldConstantVectorArithmetic and FoldConstantVectorArithmetic
functions into one FoldConstantArithmetic function.

Differential Revision: https://reviews.llvm.org/D72870
2020-01-24 18:00:58 -05:00
Simon Pilgrim 0b45c2264a [SelectionDAG] rot(x, y) --> x iff ComputeNumSignBits(x) == BitWidth(x)
Rotating an 0/-1 value by any amount will always result in the same 0/-1 value
2020-01-24 10:35:57 +00:00
Simon Pilgrim e25eee4db7 [SelectionDAG] ComputeNumSignBits - add ISD::ADD demanded elts support 2020-01-23 17:48:07 +00:00
Simon Pilgrim 0fec8acdd8 [SelectionDAG] ComputeNumSignBits - add ISD::ADD vector support
Add missing handling for (ADD (AND X, 1), -1) uniform vectors
2020-01-23 16:42:12 +00:00
Simon Pilgrim fc5bbbf328 [SelectionDAG] ComputeNumSignBits - add ISD::SUB demanded elts support 2020-01-23 16:20:48 +00:00
Simon Pilgrim 48d4ba8fb2 [SelectionDAG] Compute Known + Sign Bits - merge INSERT_VECTOR_ELT known/unknown index paths
Match the approach in SimplifyDemandedBits where we calculate the demanded elts and then have a common path for the ComputeKnownBits/ComputeNumSignBits call.
2020-01-23 13:31:37 +00:00
Simon Pilgrim 03cae086f4 [SelectionDAG] ComputeKnownBits - merge EXTRACT_VECTOR_ELT known/unknown index paths
Match the approach in SimplifyDemandedBits/ComputeNumSignBits where we calculate the demanded elts and then have a common path for the ComputeKnownBits call.
2020-01-23 11:29:16 +00:00
Simon Pilgrim 98da49d979 [SelectionDAG] Compute Known + Sign Bits - merge INSERT_SUBVECTOR known/unknown index paths
Match the approach in SimplifyDemandedBits where we calculate the demanded elts and then have a common path for the ComputeKnownBits/ComputeNumSignBits call, additionally we only ever need original demanded elts of the base vector even if the index is unknown.
2020-01-23 11:29:15 +00:00
Sander de Smalen 4cf16efe49 [AArch64][SVE] Add patterns for unpredicated load/store to frame-indices.
This patch also fixes up a number of cases in DAGCombine and
SelectionDAGBuilder where the size of a scalable vector is used in a
fixed-width context (thus triggering an assertion failure).

Reviewers: efriedma, c-rhodes, rovka, cameron.mcinally

Reviewed By: efriedma

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71215
2020-01-22 14:32:27 +00:00
Simon Pilgrim 80656fd7ae [SelectionDAG] getShiftAmountConstant - assert the type is an integer. 2020-01-22 13:52:44 +00:00
Sander de Smalen 67d4c9924c Add support for (expressing) vscale.
In LLVM IR, vscale can be represented with an intrinsic. For some targets,
this is equivalent to the constexpr:

  getelementptr <vscale x 1 x i8>, <vscale x 1 x i8>* null, i32 1

This can be used to propagate the value in CodeGenPrepare.

In ISel we add a node that can be legalized to one or more
instructions to materialize the runtime vector length.

This patch also adds SVE CodeGen support for VSCALE, which maps this
node to RDVL instructions (for scaled multiples of 16bytes) or CNT[HSD]
instructions (scaled multiples of 2, 4, or 8 bytes, respectively).

Reviewers: rengolin, cameron.mcinally, hfinkel, sebpop, SjoerdMeijer, efriedma, lattner

Reviewed by: efriedma

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68203
2020-01-22 10:09:27 +00:00
Simon Pilgrim 47f99d2ca8 [SelectionDAG] GetDemandedBits - remove ANY_EXTEND handling
Rely on SimplifyMultipleUseDemandedBits fallback instead.
2020-01-21 14:39:00 +00:00
Simon Pilgrim 9c06c10fba [SelectionDAG] GetDemandedBits - fallback to SimplifyMultipleUseDemandedBits by default.
First step towards removing SelectionDAG::GetDemandedBits entirely since it so similar to SimplifyMultipleUseDemandedBits anyhow.
2020-01-20 16:51:52 +00:00
Michael Liao 6d0d86a64d [DAG] Add helper for creating constant vector index with correct type. NFC. 2020-01-18 01:23:36 -05:00
Simon Pilgrim 1dc2f25790 [SelectionDAG] ComputeKnownBits - assert we're computing the 0'th (difference) result for the SUB/SUBC cases
Matches what we already do for the ADD/ADDC/ADDE case.
2020-01-17 13:53:57 +00:00
Simon Pilgrim f611158350 [SelectionDAG] Better ISD::ANY_EXTEND/ISD::ANY_EXTEND_VECTOR_INREG ComputeKnownBits support
Add DemandedElts handling to ISD::ANY_EXTEND and add missing ISD::ANY_EXTEND_VECTOR_INREG handling. Despite the lack of test changes this code IS being used - its just that the ANY_EXTEND ops are legalized later on (typically to ZERO_EXTEND equivalents) so we typically manage to combine later on.
2020-01-17 11:37:58 +00:00
Simon Pilgrim c05a11108b [SelectionDAG] ComputeKnownBits - merge getValidMinimumShiftAmountConstant() and generic ISD::SHL handling.
As mentioned by @nikic on rGef5debac4302, we can merge the guaranteed bottom zero bits from the shifted value, and then, if a min shift amount is known, zero out the bottom bits as well.
2020-01-14 11:51:41 +00:00
Simon Pilgrim a43b0065c5 [SelectionDAG] ComputeKnownBits - merge getValidMinimumShiftAmountConstant() and generic ISD::SRL handling.
As mentioned by @nikic on rGef5debac4302 (although that was just about SHL), we can merge the guaranteed top zero bits from the shifted value, and then, if a min shift amount is known, zero out the top bits as well.

SHL tests / handling will be added in a follow up patch.
2020-01-14 11:41:47 +00:00
Daniel Sanders a0f4600f4f Rework be15dfa88f such that it works with GlobalISel which doesn't use EVT
Summary:
be15dfa88f broke GlobalISel's usage of getSetCCInverse() which currently
appears to be limited to our out-of-tree backend. GlobalISel doesn't use
EVT's and isn't able to derive them from the information it has as it
doesn't distinguish between integer and floating point types (that
distinction is made by operations rather than values). Bring back the
bool version of getSetCCInverse() in a way that doesn't break the intent
of be15dfa88f but also allows GlobalISel to continue using it.

Reviewers: spatel, bogner, arichardson

Reviewed By: arichardson

Subscribers: rovka, hiraditya, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72309
2020-01-13 12:19:37 -08:00
Simon Pilgrim c6fcd5d115 [SelectionDAG] ComputeNumSignBits add getValidMaximumShiftAmountConstant() for ISD::SHL support
Allows us to handle non-uniform SHL shifts to determine the minimum number of sign bits remaining (based off the maximum shift amount value)
2020-01-13 18:02:37 +00:00
Simon Pilgrim 38e2c01221 [SelectionDAG] ComputeNumSignBits add getValidMinimumShiftAmountConstant() ISD::SRA support
Allows us to handle more non-uniform SRA sign bits cases
2020-01-13 16:55:02 +00:00
Simon Pilgrim 376bc39c82 [SelectionDAG] ComputeNumSignBits - Use getValidShiftAmountConstant for shift opcodes
getValidShiftAmountConstant handles out of bounds shift amounts for us, allowing us to remove the local handling.
2020-01-13 14:12:12 +00:00
Simon Pilgrim 6d1a8fd447 [SelectionDAG] ComputeKnownBits - Add DemandedElts support to getValidShiftAmountConstant/getValidMinimumShiftAmountConstant() 2020-01-13 14:12:12 +00:00
Simon Pilgrim ef5debac43 [SelectionDAG] ComputeKnownBits add getValidMinimumShiftAmountConstant() ISD::SHL support
As mentioned on D72573
2020-01-13 12:02:13 +00:00
Simon Pilgrim 8f49204f26 [SelectionDAG] ComputeKnownBits - minimum leading/trailing zero bits in LSHR/SHL (PR44526)
As detailed in https://blog.regehr.org/archives/1709 we don't make use of the known leading/trailing zeros for shifted values in cases where we don't know the shift amount value.

This patch adds support to SelectionDAG::ComputeKnownBits to use KnownBits::countMinTrailingZeros and countMinLeadingZeros to set the minimum guaranteed leading/trailing known zero bits.

Differential Revision: https://reviews.llvm.org/D72573
2020-01-13 11:08:12 +00:00
Simon Pilgrim 108279948d [SelectionDAG] Use llvm::Optional<APInt> for FoldValue.
Use llvm::Optional<APInt> instead of std::pair<APInt, bool> with the bool second being used to report success/failure of fold.
2020-01-08 16:09:24 +00:00
Matt Arsenault 4d7201e7b9 DAG: Stop trying to fold FP -(x-y) -> y-x in getNode with nsz
This was increasing the number of instructions when fsub was legalized
on AMDGPU with no signed zeros enabled. This fold should be guarded by
hasOneUse, and I don't think getNode should be doing that. The same
fold is already done as a regular combine through isNegatibleForFree.

This does require duplicating, even though isNegatibleForFree does
this combine already (and properly checks hasOneUse) to avoid one PPC
regression. In the regression, the outer fneg has nsz but the fsub
operand does not. isNegatibleForFree only sees the operand, and
doesn't see it's used from a nsz context. A nsz parameter needs to be
added and threaded through isNegatibleForFree to avoid this.
2019-12-31 22:49:51 -05:00
Kristina Bessonova cdd25a4c74 [DebugInfo][SelectionDAG] Change order while transferring SDDbgValue to another node
SelectionDAG::transferDbgValues() can 'reattach' SDDbgValue from one to
another node, but doesn't change its source order. If the destination node has
the order greater than the SDDbgValue, there are two possible issues
revealed later:

* If debug info is attached to an instruction that is the first definition
of a register, this ends up with a def-after-use and the debug info
gets 'undef' later.

* If MIR has another definition of a register above the debug info,
the debug info may represent a source variable incorrectly because
it appears (significantly) before an instruction corresponded
to this debug info.

So, the patch changes the order of an SDDbgValue when it is moved
to a node with greater order.

Reviewers: dblaikie, jmorse, aprantl

Reviewed By: aprantl

Subscribers: aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71175
2019-12-26 21:01:59 +03:00
Kevin P. Neal b1d8576b0a This adds constrained intrinsics for the signed and unsigned conversions
of integers to floating point.

This includes some of Craig Topper's changes for promotion support from
D71130.

Differential Revision: https://reviews.llvm.org/D69275
2019-12-17 10:06:51 -05:00
Alex Richardson fc83f53a86 [NFC] Implement SelectionDAG::getObjectPtrOffset() using getMemBasePlusOffset()
Summary:
This change is preparatory work to use this helper functions in more places.
In order to make this change, getMemBasePlusOffset() has been extended to
also take a SDNodeFlags parameter.

The motivation for this change is our out-of-tree CHERI backend
(https://github.com/CTSRD-CHERI/llvm-project). We use a separate register
type to store pointers (128-bit capabilities, which are effectively
unforgeable and monotonic fat pointers). These capabilities permit a
reduced set of operations and therefore use a separate ValueType (iFATPTR).
to represent pointers implemented as capabilities.
Therefore, we need to avoid using ISD::ADD for our patterns that operate
on pointers and need to use a function that chooses ISD::ADD or a new
ISD::PTRADD opcode depending on the value type.

We originally added a new DAG.getPointerAdd() function, but after this
patch series we can modify the implementation of getMemBasePlusOffset()
instead. Avoiding direct uses of ISD::ADD for pointer types will
significantly reduce the amount of assertion/instruction selection
failures for us in future upstream merges.

Reviewers: spatel

Reviewed By: spatel

Subscribers: merge_guards_bot, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71206
2019-12-13 21:40:03 +00:00
Alex Richardson ea8888d1af [NFC] Add a SDValue overload for SelectionDAG::getMemBasePlusOffset()
Summary:
This change is preparatory work to use this helper functions in more places.
Currently the function only allows integer constants offsets, but there
are cases where we can use an existing SDValue parameter.

The motivation for this change is our out-of-tree CHERI backend
(https://github.com/CTSRD-CHERI/llvm-project). We use a separate register
type to store pointers (128-bit capabilities, which are effectively
unforgeable and monotonic fat pointers). These capabilities permit a
reduced set of operations and therefore use a separate ValueType (iFATPTR).
to represent pointers implemented as capabilities.
Therefore, we need to avoid using ISD::ADD for our patterns that operate
on pointers and need to use a function that chooses ISD::ADD or a new
ISD::PTRADD opcode depending on the value type.

We originally added a new DAG.getPointerAdd() function, but after this
patch series we can modify the implementation of getMemBasePlusOffset()
instead. Avoiding direct uses of ISD::ADD for pointer types will
significantly reduce the amount of assertion/instruction selection
failures for us in future upstream merges.

Reviewers: spatel, craig.topper

Reviewed By: spatel, craig.topper

Subscribers: craig.topper, merge_guards_bot, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71205
2019-12-13 21:40:03 +00:00
Alex Richardson d9bb70acd7 [NFC] Change SelectionDAG::getMemBasePlusOffset() to use int64_t
Summary:
This change is preparatory work to use this helper functions in more places.
Currently the function only allows positive offsets, but there are cases
where we want to subtract an offset from an existing pointer.

The motivation for this change is our out-of-tree CHERI backend
(https://github.com/CTSRD-CHERI/llvm-project). We use a separate register
type to store pointers (128-bit capabilities, which are effectively
unforgeable and monotonic fat pointers). These capabilities permit a
reduced set of operations and therefore use a separate ValueType (iFATPTR).
to represent pointers implemented as capabilities.
Therefore, we need to avoid using ISD::ADD for our patterns that operate
on pointers and need to use a function that chooses ISD::ADD or a new
ISD::PTRADD opcode depending on the value type.

We originally added a new DAG.getPointerAdd() function, but after this
patch series we can modify the implementation of getMemBasePlusOffset()
instead. Avoiding direct uses of ISD::ADD for pointer types will
significantly reduce the amount of assertion/instruction selection
failures for us in future upstream merges.

Reviewers: spatel

Reviewed By: spatel

Subscribers: merge_guards_bot, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71204
2019-12-13 21:40:03 +00:00
Nicola Zaghen 97572775d2 Reland [DataLayout] Fix occurrences that size and range of pointers are assumed to be the same.
GEP index size can be specified in the DataLayout, introduced in D42123. However, there were still places
in which getIndexSizeInBits was used interchangeably with getPointerSizeInBits. This notably caused issues
with Instcombine's visitPtrToInt; but the unit tests was incorrect, so this remained undiscovered.

This fixes the buildbot failures.

Differential Revision: https://reviews.llvm.org/D68328

Patch by Joseph Faulls!
2019-12-13 14:30:21 +00:00
Alex Richardson be15dfa88f [NFC] Use EVT instead of bool for getSetCCInverse()
Summary:
The use of a boolean isInteger flag (generally initialized using
VT.isInteger()) caused errors in our out-of-tree CHERI backend
(https://github.com/CTSRD-CHERI/llvm-project).

In our backend, pointers use a separate ValueType (iFATPTR) and therefore
.isInteger() returns false. This meant that getSetCCInverse() was using the
floating-point variant and generated incorrect code for us:
`(void *)0x12033091e < (void *)0xffffffffffffffff` would return false.

Committing this change will significantly reduce our merge conflicts
for each upstream merge.

Reviewers: spatel, bogner

Reviewed By: bogner

Subscribers: wuzish, arsenm, sdardis, nemanjai, jvesely, nhaehnle, hiraditya, kbarton, jrtc27, atanasyan, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70917
2019-12-13 12:22:03 +00:00
Kerry McLaughlin 4194ca8e5a Recommit "[AArch64][SVE] Implement intrinsics for non-temporal loads & stores"
Updated pred_load patterns added to AArch64SVEInstrInfo.td by this patch
to use reg + imm non-temporal loads to fix previous test failures.

Original commit message:

Adds the following intrinsics:
  - llvm.aarch64.sve.ldnt1
  - llvm.aarch64.sve.stnt1

This patch creates masked loads and stores with the
MONonTemporal flag set when used with the intrinsics above.
2019-12-13 10:08:20 +00:00
Nicola Zaghen f798eb21ec Temporarily Revert "[DataLayout] Fix occurrences that size and range of pointers are assumed to be the same."
This reverts commit 5f6208778f.

This caused failures in Transforms/PhaseOrdering/scev-custom-dl.ll
const: Assertion `getBitWidth() == CR.getBitWidth() && "ConstantRange types don't agree!"' failed.
2019-12-12 10:29:54 +00:00
Nicola Zaghen 5f6208778f [DataLayout] Fix occurrences that size and range of pointers are assumed to be the same.
GEP index size can be specified in the DataLayout, introduced in D42123. However, there were still places
in which getIndexSizeInBits was used interchangeably with getPointerSizeInBits. This notably caused issues
with Instcombine's visitPtrToInt; but the unit tests was incorrect, so this remained undiscovered.

Differential Revision: https://reviews.llvm.org/D68328

Patch by Joseph Faulls!
2019-12-12 10:07:01 +00:00
Kerry McLaughlin c0a3ab3655 Revert "[AArch64][SVE] Implement intrinsics for non-temporal loads & stores"
This reverts commit 3f5bf35f86 as it was
causing build failures in llvm-clang-x86_64-expensive-checks:

http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-debian/builds/392
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-ubuntu/builds/1045
2019-12-11 13:58:39 +00:00
Kerry McLaughlin 3f5bf35f86 [AArch64][SVE] Implement intrinsics for non-temporal loads & stores
Summary:
Adds the following intrinsics:
  - llvm.aarch64.sve.ldnt1
  - llvm.aarch64.sve.stnt1

This patch creates masked loads and stores with the
MONonTemporal flag set when used with the intrinsics above.

Reviewers: sdesmalen, paulwalker-arm, dancgr, mgudim, efriedma, rengolin

Reviewed By: efriedma

Subscribers: tschuett, kristof.beyls, hiraditya, rkruppe, psnobl, cfe-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71000
2019-12-11 11:13:51 +00:00
Ulrich Weigand 9db13b5a7d [FPEnv] Constrained FCmp intrinsics
This adds support for constrained floating-point comparison intrinsics.

Specifically, we add:

      declare <ty2>
      @llvm.experimental.constrained.fcmp(<type> <op1>, <type> <op2>,
                                          metadata <condition code>,
                                          metadata <exception behavior>)
      declare <ty2>
      @llvm.experimental.constrained.fcmps(<type> <op1>, <type> <op2>,
                                           metadata <condition code>,
                                           metadata <exception behavior>)

The first variant implements an IEEE "quiet" comparison (i.e. we only
get an invalid FP exception if either argument is a SNaN), while the
second variant implements an IEEE "signaling" comparison (i.e. we get
an invalid FP exception if either argument is any NaN).

The condition code is implemented as a metadata string.  The same set
of predicates as for the fcmp instruction is supported (except for the
"true" and "false" predicates).

These new intrinsics are mapped by SelectionDAG codegen onto two new
ISD opcodes, ISD::STRICT_FSETCC and ISD::STRICT_FSETCCS, again
representing quiet vs. signaling comparison operations.  Otherwise
those nodes look like SETCC nodes, with an additional chain argument
and result as usual for strict FP nodes.  The patch includes support
for the common legalization operations for those nodes.

The patch also includes full SystemZ back-end support for the new
ISD nodes, mapping them to all available SystemZ instruction to
fully implement strict semantics (scalar and vector).

Differential Revision: https://reviews.llvm.org/D69281
2019-12-07 11:28:39 +01:00
Craig Topper f586fd44e4 [FPEnv] [PowerPC] Lowering ppc_fp128 StrictFP Nodes to libcalls
This is an alternative to D64662 that shares more code between
strict and non-strict nodes. It's modeled after the implementation
that I did for softening.

Differential Revision: https://reviews.llvm.org/D70867
2019-12-03 14:11:21 -08:00
Roman Lebedev 9a20c79ddc
[NFC][KnownBits] Add getMinValue() / getMaxValue() methods
As it can be seen from accompanying cleanup, it is not unheard of
to write `~Known.Zero` meaning "what maximal value can this KnownBits
produce". But i think `~Known.Zero` isn't *that* self-explanatory,
as compared to a method with a name.

Note that not all `~Known.Zero` places were cleaned up,
only those where this arguably improves things.
2019-12-03 20:04:51 +03:00
David Green b5315ae8ff [Codegen][ARM] Add addressing modes from masked loads and stores
MVE has a basic symmetry between it's normal loads/store operations and
the masked variants. This means that masked loads and stores can use
pre-inc and post-inc addressing modes, just like the standard loads and
stores already do.

To enable that, this patch adds all the relevant infrastructure for
treating masked loads/stores addressing modes in the same way as normal
loads/stores.

This involves:
- Adding an AddressingMode to MaskedLoadStoreSDNode, along with an extra
   Offset operand that is added after the PtrBase.
- Extending the IndexedModeActions from 8bits to 16bits to store the
   legality of masked operations as well as normal ones. This array is
   fairly small, so doubling the size still won't make it very large.
   Offset masked loads can then be controlled with
   setIndexedMaskedLoadAction, similar to standard loads.
- The same methods that combine to indexed loads, such as
   CombineToPostIndexedLoadStore, are adjusted to handle masked loads in
   the same way.
- The ARM backend is then adjusted to make use of these indexed masked
   loads/stores.
- The X86 backend is adjusted to hopefully be no functional changes.

Differential Revision: https://reviews.llvm.org/D70176
2019-11-26 16:21:01 +00:00
Hiroshi Yamauchi 52e377497d [PGO][PGSO] DAG.shouldOptForSize part.
Summary:
(Split of off D67120)

SelectionDAG::shouldOptForSize changes for profile guided size optimization.

Reviewers: davidxl

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70095
2019-11-21 14:16:00 -08:00
Serge Pavlov 0c50c0b055 [FEnv] File with properties of constrained intrinsics
Summary
In several places we need to enumerate all constrained intrinsics or IR
nodes that should be represented by them. It is easy to miss some of
the cases. To make working with these intrinsics more convenient and
robust, this change introduces file containing definitions of all
constrained intrinsics and some of their properties. This file can be
included to generate constrained intrinsics processing code.

Reviewers: kpn, andrew.w.kaylor, cameron.mcinally, uweigand

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69887
2019-11-20 13:30:07 +07:00
Graham Hunter 3f08ad611a [SVE][CodeGen] Scalable vector MVT size queries
* Implements scalable size queries for MVTs, split out from D53137.

* Contains a fix for FindMemType to avoid using scalable vector type
  to contain non-scalable types.

* Explicit casts for several places where implicit integer sign
  changes or promotion from 32 to 64 bits caused problems.

* CodeGenDAGPatterns will treat scalable and non-scalable vector types
  as different.

Reviewers: greened, cameron.mcinally, sdesmalen, rovka

Reviewed By: rovka

Differential Revision: https://reviews.llvm.org/D66871
2019-11-18 12:30:59 +00:00
Simon Pilgrim 97725707f4 Fix uninitialized variable warning. NFCI. 2019-11-02 14:42:38 +00:00
Kerry McLaughlin da720a38b9 [AArch64][SVE] Implement masked load intrinsics
Summary:
Adds support for codegen of masked loads, with non-extending,
zero-extending and sign-extending variants.

Reviewers: huntergr, rovka, greened, dmgreen

Reviewed By: dmgreen

Subscribers: dmgreen, samparker, tschuett, kristof.beyls, hiraditya, rkruppe, psnobl, cfe-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68877
2019-10-28 10:06:14 +00:00
Sanjay Patel 85a2146c15 [SDAG] fold insert_vector_elt with undef index
Similar to:
rG4c47617627fb

This makes the DAG behavior consistent with IR's insertelement.

https://bugs.llvm.org/show_bug.cgi?id=42689

I've tried to maintain test intent for AArch64 and WebAssembly
by replacing undef index operands with something else.
2019-10-27 15:28:43 -04:00
Sanjay Patel 4c47617627 [SDAG] fold extract_vector_elt with undef index
This makes the DAG behavior consistent with IR's extractelement after:
rGb32e4664a715

https://bugs.llvm.org/show_bug.cgi?id=42689

I've tried to maintain test intent for WebAssembly.
The AMDGPU test is trying to test for crashing or other bad behavior,
but I'm not sure if that's possible after this change.
2019-10-25 19:27:26 -04:00
Kevin P. Neal 1c3d19c82d [FPEnv] Add constrained intrinsics for lrint and lround
Earlier in the year intrinsics for lrint, llrint, lround and llround were
added to llvm. The constrained versions are now implemented here.

Reviewed by:	andrew.w.kaylor, craig.topper, cameron.mcinally
Approved by:	craig.topper
Differential Revision:	https://reviews.llvm.org/D64746

llvm-svn: 373900
2019-10-07 13:20:00 +00:00
Tamas Berghammer 421a186fb4 Support MemoryLocation::UnknownSize in TargetLowering::IntrinsicInfo
Summary:
Previously IntrinsicInfo::size was an unsigned what can't represent the
64 bit value used by MemoryLocation::UnknownSize.

Reviewers: jmolloy

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68219

llvm-svn: 373214
2019-09-30 14:44:24 +00:00
Guillaume Chatelet 18f805a7ea [Alignment][NFC] Remove unneeded llvm:: scoping on Align types
llvm-svn: 373081
2019-09-27 12:54:21 +00:00
Simon Pilgrim 20f4afc5a7 [DAG] Pull out minimum shift value calc into a helper function. NFCI.
llvm-svn: 372856
2019-09-25 12:28:56 +00:00
Simon Pilgrim c8a9ae4ce2 [SelectionDAG] computeKnownBits/ComputeNumSignBits - cleanup demanded/unknown paths. NFCI.
Merge the calls, just adjust the demandedelts if we have a valid extract_subvector constant index, else demand all elts.

llvm-svn: 372521
2019-09-22 18:47:12 +00:00
Simon Pilgrim c65dd89804 [DAG] Add SelectionDAG::MaxRecursionDepth constant
As commented on D67557 we have a lot of uses of depth checks all using magic numbers.

This patch adds the SelectionDAG::MaxRecursionDepth constant and moves over some general cases to use this explicitly.

Differential Revision: https://reviews.llvm.org/D67711

llvm-svn: 372315
2019-09-19 12:58:43 +00:00
Philip Reames 079e210463 [SDAG] Update generic code to conservatively check for isAtomic in addition to isVolatile
This is the first sweep of generic code to add isAtomic bailouts where appropriate. The intention here is to have the switch from AtomicSDNode to LoadSDNode/StoreSDNode be close to NFC; that is, I'm not looking to allow additional optimizations at this time. That will come later.  See D66309 for context.

Differential Revision: https://reviews.llvm.org/D66318

llvm-svn: 371786
2019-09-12 22:49:17 +00:00
Guillaume Chatelet b6722af068 [Alignment] Use Align for TargetLowering::MinStackArgumentAlignment
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: sdardis, nemanjai, hiraditya, kbarton, jrtc27, MaskRay, atanasyan, jsji, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67288

llvm-svn: 371498
2019-09-10 09:01:18 +00:00
Craig Topper 5ebd0a6e88 [SelectionDAG] Remove ISD::FP_ROUND_INREG
I don't think anything in tree creates this node. So all of this
code appears to be dead.

Code coverage agrees
http://lab.llvm.org:8080/coverage/coverage-reports/llvm/coverage/Users/buildslave/jenkins/workspace/clang-stage2-coverage-R/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp.html

Differential Revision: https://reviews.llvm.org/D67312

llvm-svn: 371431
2019-09-09 17:54:44 +00:00
Kevin P. Neal ddf13c00ed [FPEnv] Add fptosi and fptoui constrained intrinsics.
This implements constrained floating point intrinsics for FP to signed and
unsigned integers.

Quoting from D32319:
The purpose of the constrained intrinsics is to force the optimizer to
respect the restrictions that will be necessary to support things like the
STDC FENV_ACCESS ON pragma without interfering with optimizations when
these restrictions are not needed.

Reviewed by:	Andrew Kaylor, Craig Topper, Hal Finkel, Cameron McInally, Roman Lebedev, Kit Barton
Approved by:	Craig Topper
Differential Revision:	http://reviews.llvm.org/D63782

llvm-svn: 370228
2019-08-28 16:33:36 +00:00
Matt Arsenault 2910184936 DAG: computeNumSignBits for MUL
Copied directly from the IR version.

Most of the testcases I've added for this are somewhat problematic
because they really end up testing the yet to be implemented version
for MUL_I24/MUL_U24.

llvm-svn: 370099
2019-08-27 19:05:33 +00:00
Craig Topper f43106e341 [SelectionDAG] Add a node creation debug message to getMachineNode.
llvm-svn: 369204
2019-08-18 06:28:00 +00:00
Sanjay Patel 57d459309d [SDAG][x86] check for relaxed math when matching an FP reduction
If the last step in an FP add reduction allows reassociation and doesn't care
about -0.0, then we are free to recognize that computation as a reduction
that may reorder the intermediate steps.

This is requested directly by PR42705:
https://bugs.llvm.org/show_bug.cgi?id=42705
and solves PR42947 (if horizontal math instructions are actually faster than
the alternative):
https://bugs.llvm.org/show_bug.cgi?id=42947

Differential Revision: https://reviews.llvm.org/D66236

llvm-svn: 368995
2019-08-15 12:43:15 +00:00
Sanjay Patel ecccf29e6c [SDAG] move variable closer to use; NFC
llvm-svn: 368905
2019-08-14 19:46:15 +00:00
Amy Huang 0b870b969f Recommit "[MS] Emit S_HEAPALLOCSITE debug info in Selection DAG"
with a fix to clear the SDNode map when SelectionDAG is cleared.

llvm-svn: 368230
2019-08-07 22:49:40 +00:00
Cullen Rhodes ced419f4d7 [SelectionDAG] Extend base addressing modes supported by MGATHER/MSCATTER
Summary:
Before this patch MGATHER/MSCATTER is capable of representing all
common addressing modes, but only when illegal types are used.
This patch adds an IndexType property so more representations
are available when using legal types only.

Original modes:
 vector of bases
 base + vector of signed scaled offsets

New modes:
 base + vector of signed unscaled offsets
 base + vector of unsigned scaled offsets
 base + vector of unsigned unscaled offsets

The current behaviour of addressing modes for gather/scatter remains
unchanged.

Patch by Paul Walker.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D65636

llvm-svn: 368008
2019-08-06 09:46:13 +00:00
Guillaume Chatelet 65e4b47aad [LLVM][Alignment] Introduce Alignment Type in DataLayout
Summary:
This is patch is part of a serie to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, jfb, jakehehrlich

Subscribers: hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65521

Make getFunctionPtrAlign() return MaybeAlign

llvm-svn: 367817
2019-08-05 09:00:43 +00:00
Craig Topper 76f0f2e0f0 [SelectionDAG] Add node creation debug message to getMemIntrinsicNode.
llvm-svn: 367771
2019-08-04 02:32:06 +00:00
Craig Topper 388df2ea19 [SelectionDAG] Use APInt::isSubsetOf/intersects to simplify some code.
Also use KnownBits::isNegative/isNonNegative to further simplify.

llvm-svn: 367518
2019-08-01 06:06:21 +00:00
Michael Berg 005d705d43 Migrate some more fadd and fsub cases away from UnsafeFPMath control to utilize NoSignedZerosFPMath options control
Summary: Honoring no signed zeroes is also available as a user control through clang separately regardless of fastmath or UnsafeFPMath context, DAG guards should reflect this context.

Reviewers: spatel, arsenm, hfinkel, wristow, craig.topper

Reviewed By: spatel

Subscribers: rampitec, foad, nhaehnle, wuzish, nemanjai, jvesely, wdng, javed.absar, MaskRay, jsji

Differential Revision: https://reviews.llvm.org/D65170

llvm-svn: 367486
2019-07-31 21:57:28 +00:00
Peter Collingbourne 33773d5cfc SelectionDAG, MI, AArch64: Widen target flags fields/arguments from unsigned char to unsigned.
This makes the field wider than MachineOperand::SubReg_TargetFlags so that
we don't end up silently truncating any higher bits. We should still catch
any bits truncated from the MachineOperand field as a consequence of the
assertion in MachineOperand::setTargetFlags().

Differential Revision: https://reviews.llvm.org/D65465

llvm-svn: 367474
2019-07-31 20:14:09 +00:00
Simon Pilgrim 8a52671782 [SelectionDAG] Check for any recursion depth greater than or equal to limit instead of just equal the limit.
If anything called the recursive isKnownNeverNaN/computeKnownBits/ComputeNumSignBits/SimplifyDemandedBits/SimplifyMultipleUseDemandedBits with an incorrect depth then we could continue to recurse if we'd already exceeded the depth limit.

This replaces the limit check (Depth == 6) with a (Depth >= 6) to make sure that we don't circumvent it. 

This causes a couple of regressions as a mixture of calls (SimplifyMultipleUseDemandedBits + combineX86ShufflesRecursively) were calling with depths that were already over the limit. I've fixed SimplifyMultipleUseDemandedBits to not do this. combineX86ShufflesRecursively is trickier as we get a lot of regressions if we reduce its own limit from 8 to 6 (it also starts at Depth == 1 instead of Depth == 0 like the others....) - I'll see what I can do in future patches.

llvm-svn: 367171
2019-07-27 12:48:46 +00:00
Simon Pilgrim a424a1f351 [SelectionDAG] GetDemandedBits - update SIGN_EXTEND_INREG op to just call SimplifyMultipleUseDemandedBits.
llvm-svn: 367098
2019-07-26 10:03:07 +00:00
Simon Pilgrim d0164fc525 [SelectionDAG] GetDemandedBits - update OR/XOR ops to just call SimplifyMultipleUseDemandedBits.
Eventually all of these will be moved over, but we create nodes in GetDemandedBits recursion at the moment which causes regressions when we try to remove them all.

llvm-svn: 367092
2019-07-26 09:13:29 +00:00
Simon Pilgrim 2bf871be4c Fix signed/unsigned comparison warning. NFCI.
llvm-svn: 366935
2019-07-24 17:44:22 +00:00
Simon Pilgrim 7d318b2bb1 [DAGCombine] matchBinOpReduction - add partial reduction matching
This patch adds support for recognizing cases where a larger vector type is being used to reduce just the elements in the lower subvector:

e.g. <8 x i32> reduction pattern in a <16 x i32> vector:

<4,5,6,7,u,u,u,u,u,u,u,u,u,u,u,u>
<2,3,u,u,u,u,u,u,u,u,u,u,u,u,u,u>
<1,u,u,u,u,u,u,u,u,u,u,u,u,u,u,u>

matchBinOpReduction returns the lower extracted subvector in such cases, assuming isExtractSubvectorCheap accepts the extraction.

I've only enabled it for X86 reduction sums so far. I intend to enable it for the bitop/minmax cases in future patches, and eventually I think its worth turning it on all the time. This is mainly just a case of ensuring calls to matchBinOpReduction don't make assumptions on the vector width based on the original vector extraction.

Fixes the x86 partial reduction sum cases in PR33758 and PR42023.

Differential Revision: https://reviews.llvm.org/D65047

llvm-svn: 366933
2019-07-24 17:29:56 +00:00
Simon Pilgrim 3f01c7197f [SelectionDAG] makeEquivalentMemoryOrdering - early out for equal chains (PR42727)
If we are already using the same chain for the old/new memory ops then just return.

Fixes PR42727 which had getLoad() reusing an existing node.

llvm-svn: 366922
2019-07-24 16:53:14 +00:00
Guillaume Chatelet 336f3e1601 Fixing @llvm.memcpy not honoring volatile.
This is explicitly not addressing target-specific code, or calls to memcpy.

Summary: https://bugs.llvm.org/show_bug.cgi?id=42254

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63215

llvm-svn: 365449
2019-07-09 09:53:36 +00:00
James Molloy fa4aac7335 [SelectionDAG] Propagate alias metadata to target intrinsic nodes
When a target intrinsic has been determined to touch memory, we construct a MachineMemOperand during SDAG construction. In this case, we should propagate AAMDNodes metadata to the MachineMemOperand where available.

Differential revision: https://reviews.llvm.org/D64131

llvm-svn: 365043
2019-07-03 14:33:29 +00:00
Craig Topper 4d0feb28ec [SelectionDAG] Use the memory VT instead of result VT for FoldingSet profiling in getMaskedLoad/getMaskedStore.
This matches what is done by the Profile function. Otherwise CSE
won't work properly.

llvm-svn: 364717
2019-06-30 06:46:33 +00:00
Roman Lebedev b0ecc1cc6b [X86] X86DAGToDAGISel::matchBitExtract(): pattern b: truncation awareness
Summary:
(Not so) boringly identical to pattern a (D62786)
Not yet sure how do deal with the last pattern c.

Reviewers: RKSimon, craig.topper, spatel

Reviewed By: RKSimon

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D62793

llvm-svn: 364418
2019-06-26 12:19:39 +00:00
Simon Pilgrim 8c49366c9b [DAGCombiner] Support (shl (ext (shl x, c1)), c2) -> 0 non-uniform folds.
Use matchBinaryPredicate instead of isConstOrConstSplat to let us handle non-uniform shift cases. 

This requires us to tweak matchBinaryPredicate to allow it to (optionally) handle constants with different type widths.

llvm-svn: 363792
2019-06-19 12:25:29 +00:00
Simon Pilgrim ef78e55205 [SelectionDAG] Fold insert_subvector(undef, extract_subvector(v, c), c) -> v in getNode
This is already done in DAGCombiner::visitINSERT_SUBVECTOR, but this helps a number of shuffles across different vector widths recognise when they come from the same source.

llvm-svn: 363542
2019-06-17 10:14:52 +00:00
Simon Pilgrim ad298f86b7 [SelectionDAG] ComputeNumSignBits - support constant pool values from target
As I mentioned on D61887 we don't get many hits on ComputeNumSignBits as we did on computeKnownBits.

The case we do get is interesting though - it allows us to use the 'ConditionalNegate' combine in combineLogicBlendIntoPBLENDV to remove a select.

It comes too late for SSE41 (BLENDV) cases, but SSE2 tests can hit it now. We should probably try to make use of this for SSE41+ targets as well - avoiding variable blends is usually a good idea. I'll investigate as a followup.

Differential Revision: https://reviews.llvm.org/D62777

llvm-svn: 362486
2019-06-04 10:49:06 +00:00
Simon Pilgrim 3178546a27 [SelectionDAG] ComputeNumSignBits - clang-format + improve *EXTLOAD comments. NFCI.
Pre-commit requested for D62777.

llvm-svn: 362485
2019-06-04 10:17:56 +00:00
Simon Pilgrim 3018d505a3 [SelectionDAG] Add fpto[us]i(undef) --> undef constant fold
Follow up to D62807.

Differential Revision: https://reviews.llvm.org/D62811

llvm-svn: 362483
2019-06-04 10:04:55 +00:00
Simon Pilgrim cb7e4e8193 [SelectionDAG] Add [us]itofp(undef) --> 0 constant fold (PR39205)
We were missing this fold in the DAG, which I've copied directly from llvm::ConstantFoldCastInstruction

Differential Revision: https://reviews.llvm.org/D62807

llvm-svn: 362397
2019-06-03 13:02:07 +00:00
Simon Pilgrim ffb4d2bff7 [DAG] isBitwiseNot / isConstOrConstSplat - add support for build vector undefs + truncation (PR41020)
Add (opt-in) support for implicit truncation to isConstOrConstSplat, which allows us to match truncated 'all ones' cases in isBitwiseNot.

PR41020 compares against using ISD::isBuildVectorAllOnes() instead, but that predicate silently accepts any UNDEF elements in the build vector which might not be what we want in isBitwiseNot - so I've added an opt-in 'AllowUndefs' flag that is set to false by default but will allow us to enable it on individual cases where its safe.

Differential Revision: https://reviews.llvm.org/D62783

llvm-svn: 362323
2019-06-02 11:56:39 +00:00
Craig Topper bc9e04d0c3 [SelectionDAG] Make the code in mutateStrictFPToFP less aware of how many operands each node has. NFCI
Just copy all of the operands except the chain and call MorphNode on that.
This removes the IsUnary and IsTernary flags.

Also always get the result type from the result type of the original
nodes. Previously we got it from the operand except for two nodes
where that didn't work.

llvm-svn: 362269
2019-05-31 22:18:45 +00:00
Sanjay Patel 2f99d009c1 [SelectionDAG] fold concat of extract subvectors
This is derived from the related fold for build vectors.
We also have a version of this in DAGCombiner. The benefit of
having this fold at node creation time is (1) efficiency and
(2) preventing infinite looping from creating patterns that
should not exist in the first place.

Currently, the inf-loop could happen with MergeConsecutiveStores()
because it naively creates concat of extracts when forming a wider
vector store. That could fight with target-specific store narrowing.

llvm-svn: 361780
2019-05-27 20:26:21 +00:00
Sanjay Patel e13ae3e4d8 [SelectionDAG] fix formatting and redundant comments; NFC
There's a possible missing fold here for extracting from the
same source vector. It's similar to a check that we use to
squash a build vector with all extracted elements from the
same source vector.

llvm-svn: 361778
2019-05-27 18:26:43 +00:00
Simon Pilgrim ebb053b139 [SelectionDAG] GetDemandedBits - add demanded elements wrapper implementation
The DemandedElts variable is pretty much inert at the moment - the original GetDemandedBits implementation calls it with an 'all ones' DemandedElts value so the function is active and behaves exactly as it used to.

llvm-svn: 361773
2019-05-27 16:39:25 +00:00
Simon Pilgrim 06e02856ab [SelectionDAG] GetDemandedBits - cleanup to more closely match SimplifyDemandedBits. NFCI.
Prep work before adding demanded elts support.

llvm-svn: 361739
2019-05-26 18:58:14 +00:00
Simon Pilgrim 2916b9e28c [SelectionDAG] MaskedValueIsZero - add demanded elements implementation
Will be used in an upcoming patch but I've updated the original implementation to call this to ensure test coverage.

llvm-svn: 361738
2019-05-26 18:43:44 +00:00
Simon Pilgrim 95b8d9bbf8 [SelectionDAG] computeKnownBits - support constant pool values from target
This patch adds the overridable TargetLowering::getTargetConstantFromLoad function which allows targets to return any constant value loaded by a LoadSDNode node - only X86 makes use of this so far but everything should be in place for other targets.

computeKnownBits then uses this function to improve codegen, notably vector code after legalization.

A future commit will do the same for ComputeNumSignBits but computeKnownBits sees the bigger benefit.

This required a couple of fixes:
* SimplifyDemandedBits must early-out for getTargetConstantFromLoad cases to prevent infinite loops of constant regeneration (similar to what we already do for BUILD_VECTOR).
* Fix a DAGCombiner::visitTRUNCATE issue as we had trunc(shl(v8i32),v8i16) <-> shl(trunc(v8i16),v8i32) infinite loops after legalization on AVX512 targets.

Differential Revision: https://reviews.llvm.org/D61887

llvm-svn: 361620
2019-05-24 10:03:11 +00:00
Sanjay Patel 10f6b39899 [SelectionDAG] fold insert subvector of undef into undef
DAGCombiner simplifies this more liberally as:
  // If inserting an UNDEF, just return the original vector.
  if (N1.isUndef())
    return N0;

So there's no way to make this visible in output AFAIK, but
doing this at node creation time should be slightly more efficient.

llvm-svn: 361287
2019-05-21 18:53:53 +00:00
Petar Jovanovic e85bbf564d [DebugInfoMetadata] Refactor DIExpression::prepend constants (NFC)
Refactor DIExpression::With* into a flag enum in order to be less
error-prone to use (as discussed on D60866).

Patch by Djordje Todorovic.

Differential Revision: https://reviews.llvm.org/D61943

llvm-svn: 361137
2019-05-20 10:35:57 +00:00
Reid Kleckner 4882490349 [codeview] Fix SDNode representation of annotation labels
Before this change, they were erroneously constructed with the EH_LABEL
SDNode opcode, which caused other passes to interact with them in
incorrect ways. See the FIXME about fastisel that this addresses in the
existing test case.

Fixes PR41890

llvm-svn: 360818
2019-05-15 21:46:05 +00:00
Kevin P. Neal 5987749e33 Add constrained fptrunc and fpext intrinsics.
The new fptrunc and fpext intrinsics are constrained versions of the
regular fptrunc and fpext instructions.

Reviewed by:	Andrew Kaylor, Craig Topper, Cameron McInally, Conner Abbot
Approved by:	Craig Topper
Differential Revision: https://reviews.llvm.org/D55897

llvm-svn: 360581
2019-05-13 13:23:30 +00:00
Sanjay Patel 902b3ecdad [SelectionDAG] fold 'fneg undef' to undef
This is extracted from the original draft of D61419 with some additional tests.
We don't currently get this in IR (it's conservatively turned into a NaN),
but presumably that'll get updated as we add real IR support for 'fneg'
rather than 'fsub -0.0, x'.

The x86-32 run shows the following, and I haven't looked further to see why,
but that seems to be independent:
  Legalizing: t1: f32 = undef
  Trying to expand node
  Creating fp constant: t4: f32 = ConstantFP<0.000000e+00>

Differential Revision: https://reviews.llvm.org/D61516

llvm-svn: 360296
2019-05-08 22:19:52 +00:00
Simon Pilgrim 0f89b76b84 [SelectionDAG] Use any_of/all_of where possible. NFCI.
llvm-svn: 359974
2019-05-05 10:30:04 +00:00
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