Commit Graph

9147 Commits

Author SHA1 Message Date
Matt Arsenault e8eb567e17 DAG: Avoid bitcast/ext/build_vector combine
This avoids regressions in a future AMDGPU change
to make v4i16/v4f16 legal. For these types, build_vector
is implemented as bitcasted operations on v2i32. This
combine was creating v4i16s out of what would have been
already been a v2i32 build_vector, creating a mess
of nodes that never get cleaned up.

I'm not sure this is the right condition to check.
I initially tried just checking for the legality of the
new build_vector. This works for my case, but breaks dozens
of x86 tests. A Mips test seems to show some improvement
or at least a neutral change. I don't want to think
about how long it would take to analyze the set of
different x86 vector operations impacted.

Test included in future commit.

llvm-svn: 334218
2018-06-07 19:42:27 +00:00
Michael Berg cc1c4b6912 guard fsqrt with fmf sub flags
Summary:
This change uses fmf subflags to guard optimizations as well as unsafe. These changes originated from D46483.
It contains only context for fsqrt.


Reviewers: spatel, hfinkel, arsenm

Reviewed By: spatel

Subscribers: hfinkel, wdng, andrew.w.kaylor, wristow, efriedma, nemanjai

Differential Revision: https://reviews.llvm.org/D47749

llvm-svn: 334113
2018-06-06 18:47:55 +00:00
Michael Berg 96925fe0df guard fneg with fmf sub flags
Summary: This change uses fmf subflags to guard optimizations as well as unsafe. These changes originated from D46483.

Reviewers: spatel, hfinkel

Reviewed By: spatel

Subscribers: nemanjai

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

llvm-svn: 334037
2018-06-05 18:49:47 +00:00
Matt Arsenault 191bc71541 DAG: Stop dropping invariant/dereferencable
When legalizing illegal FP load results, this was
for some reason dropping the invariant and dereferencable
memory flags. There doesn't seem to be any reason for this,
and the equivalent isn't done for integer loads.

Fixes an issue in a future AMDGPU commit where some identical
loads fail to merge because one of the loads ends up
dropping the flags.

llvm-svn: 334020
2018-06-05 14:52:24 +00:00
Reid Kleckner adcaddb6da Fix -Wcovered-switch-default warning and clang-format it
llvm-svn: 333967
2018-06-04 23:47:29 +00:00
Scott Linder ba81d7f1eb [CodeGen] Always update divergence in SelectionDAG::UpdateNodeOperands
Some overloads failed to update divergence.

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

llvm-svn: 333947
2018-06-04 20:19:45 +00:00
Amaury Sechet da661e9236 [DAGcombine] Teach the combiner about -a = ~a + 1
Summary: This include variant for add, uaddo and addcarry. usubo and subcarry require the carry to be flipped to preserve semantic, but we chose to do the transform anyway in that case as to push the transform down the carry chain.

Reviewers: efriedma, spatel, RKSimon, zvi, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46505

llvm-svn: 333943
2018-06-04 19:23:22 +00:00
Amaury Sechet 93a7d2aa3c Get rid of SETCCE
Summary: It has been deprecated in favor of SETCCCARRY for a year now and isn't used by any in tree backend.

Reviewers: efriedma, craig.topper, dblaikie, bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47685

llvm-svn: 333939
2018-06-04 18:36:22 +00:00
Krzysztof Parzyszek 623eb54361 [SelectionDAG] Add missing closing parentheses in comments, NFC
llvm-svn: 333907
2018-06-04 14:54:53 +00:00
Nirav Dave fc9a700f94 [DAG] Avoid checking for consecutive stores in store merge. NFCI.
llvm-svn: 333766
2018-06-01 15:05:55 +00:00
Nirav Dave 39ece11ae5 [DAG] Simplify Expression. NFC.
llvm-svn: 333765
2018-06-01 15:05:30 +00:00
Nirav Dave 0fc27acaa2 [DAG] Remove untriggerable check. NFCI.
Candidate check precludes this check.

llvm-svn: 333764
2018-06-01 15:05:05 +00:00
Nirav Dave a74921a696 [DAG] Prune store merge legal store check to stop invalid size. NFCI.
Do not consider store sizes large than the maximum legal store size.

llvm-svn: 333763
2018-06-01 15:04:40 +00:00
Krzysztof Parzyszek 0b6187c1a9 [SelectionDAG] Expand UADDO/USUBO into ADD/SUBCARRY if legal for target
Additionally, implement handling of ADD/SUBCARRY on Hexagon, utilizing
the UADDO/USUBO expansion.

Differential Revision: https://reviews.llvm.org/D47559

llvm-svn: 333751
2018-06-01 14:00:32 +00:00
Heejin Ahn 5ef4d5f9c1 [WebAssembly] Support instruction selection for catching exceptions
Summary:
This lowers exception catching-related instructions:
1. Lowers `wasm.catch` intrinsic to `catch` instruction
2. Removes `catchpad` and `cleanuppad` instructions; they are not
necessary after isel phase. (`MachineBasicBlock::isEHFuncletEntry()` or
`MachineBasicBlock::isEHPad()` can be used instead.)
3. Lowers `catchret` and `cleanupret` instructions to pseudo `catchret`
and `cleanupret` instructions in isel, which will be replaced with other
instructions in `WebAssemblyExceptionPrepare` pass.
4. Adds 'WebAssemblyExceptionPrepare` pass, which is for running various
transformation for EH. Currently this pass only replaces `catchret` and
`cleanupret` instructions into appropriate wasm instructions to make
this patch successfully run until the end.

Currently this does not handle lowering of intrinsics related to LSDA
info generation (`wasm.landingpad.index` and `wasm.lsda`), because they
cannot be tested without implementing `EHStreamer`'s wasm-specific
handlers. They are marked as TODO, which is needed to make isel pass.
Also this does not generate `try` and `end_try` markers yet, which will
be handled in later patches.

This patch is based on the first wasm EH proposal.
(https://github.com/WebAssembly/exception-handling/blob/master/proposals/Exceptions.md)

Reviewers: dschuff, majnemer

Subscribers: jfb, sbc100, jgravelle-google, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D44090

llvm-svn: 333705
2018-05-31 22:25:54 +00:00
Matt Arsenault ab2b79cb97 DAG: Remove redundant version of getRegisterTypeForCallingConv
There seems to be no real reason to have these separate copies.
The existing implementations just copy each other for x86.
For Mips there is a subtle difference, which is just a bug
since it changes based on the context where which one was called.
Dropping this version, all tests pass. If I try to merge them
to match the removed version, a test fails.

llvm-svn: 333440
2018-05-29 17:42:26 +00:00
Cameron McInally b1bb60aec9 [StrictFP] Make getStrictFPOpcodeAction(...) more accessible
NFCI. This function will be reused in upcoming patches.

Differential Revision: https://reviews.llvm.org/D47380

llvm-svn: 333433
2018-05-29 16:49:32 +00:00
Heejin Ahn 1e4d35044f [WebAssembly] Add functions for EHScopes
Summary:
There are functions using the term 'funclet' to refer to both
1. an EH scopes, the structure of BBs that starts with
catchpad/cleanuppad and ends with catchret/cleanupret, and
2. a small function that gets outlined in AsmPrinter, which is the
original meaning of 'funclet'.

So far the two have been the same thing; EH scopes are always outlined
in AsmPrinter as funclets at the end of the compilation pipeline. But
now wasm also uses scope-based EH but does not outline those, so we now
need to correctly distinguish those two use cases in functions.

This patch splits `MachineBasicBlock::isFuncletEntry` into
`isFuncletEntry` and `isEHScopeEntry`, and
`MachineFunction::hasFunclets` into `hasFunclets` and `hasEHScopes`, in
order to distinguish the two different use cases. And this also changes
some uses of the term 'funclet' to 'scope' in `getFuncletMembership` and
change the function name to `getEHScopeMembership` because this function
is not about outlined funclets but about EH scope memberships.

This change is in the same vein as D45559.

Reviewers: majnemer, dschuff

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

Differential Revision: https://reviews.llvm.org/D47005

llvm-svn: 333045
2018-05-23 00:32:46 +00:00
Sanjay Patel 17a870f07c [DAG] fold FP binops with undef operands to NaN
This is the FP sibling of D43141 with the corresponding IR change in rL327212.

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

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

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

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

llvm-svn: 332920
2018-05-21 23:54:19 +00:00
Roman Lebedev 9f65d16d5d [DAGCombiner] isAllOnesConstantOrAllOnesSplatConstant(): look through bitcasts
Summary:
As pointed out in D46528, we errneously transform cases like `xor X, -1`,
even though we use said function.
It's because the `-1` is actually a bitcast there.
So i think we can just look through it in the function.

Differential Revision: https://reviews.llvm.org/D47156

llvm-svn: 332905
2018-05-21 21:41:10 +00:00
Roman Lebedev 7772de25d0 [DAGCombine][X86][AArch64] Masked merge unfolding: vector edition.
Summary:
This **appears** to be the last missing piece for the masked merge pattern handling in the backend.

This is [[ https://bugs.llvm.org/show_bug.cgi?id=37104 | PR37104 ]].

[[ https://bugs.llvm.org/show_bug.cgi?id=6773 | PR6773 ]] will introduce an IR canonicalization that is likely bad for the end assembly.
Previously, `andps`+`andnps` / `bsl` would be generated. (see `@out`)
Now, they would no longer be generated  (see `@in`), and we need to make sure that they are generated.

Differential Revision: https://reviews.llvm.org/D46528

llvm-svn: 332904
2018-05-21 21:41:02 +00:00
Craig Topper 25444c852a [DAGCombiner] Use computeKnownBits to match rotate patterns that have had their amount masking modified by simplifyDemandedBits
SimplifyDemandedBits can remove bits from the masks for the shift amounts we need to see to detect rotates.

This patch uses zeroes from computeKnownBits to fill in some of these mask bits to make the match work.

As currently written this calls computeKnownBits even when the mask hasn't been simplified because it made the code simpler. If we're worried about compile time performance we can improve this.

I know we're talking about making a rotate intrinsic, but hopefully we can go ahead and do this change and just make sure the rotate intrinsic also handles it.

Differential Revision: https://reviews.llvm.org/D47116

llvm-svn: 332895
2018-05-21 21:09:18 +00:00
Matt Arsenault 9fc8593a77 DAG: Fix crash on shift with large shift amounts
Fixes bug 37521.

llvm-svn: 332774
2018-05-18 21:54:16 +00:00
Nirav Dave 11fd14c1ac [DAG] Prune cycle check in store merge.
As part of merging stores we check that fusing the nodes does not
cause a cycle due to one candidate store being indirectly dependent on
another store (this may happen via chained memory copies). This is
done by searching if a store is a predecessor to another store's
value.

Prune the search at the candidate search's root node which is a
predecessor to all candidate stores. This reduces the
size of the subgraph searched in large basic blocks.

Reviewers: jyknight

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D46955

llvm-svn: 332490
2018-05-16 16:48:20 +00:00
Nirav Dave d9d86cb738 [DAG] Defer merge store cycle checking to just before merge. NFCI.
llvm-svn: 332489
2018-05-16 16:47:54 +00:00
Sirish Pande cabe50a308 [AArch64] Gangup loads and stores for pairing.
Keep loads and stores together (target defines how many loads
and stores to gang up), such that it will help in pairing
and vectorization.

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

llvm-svn: 332482
2018-05-16 15:36:52 +00:00
Alexander Richardson 8f44579d0b Emit a left-shift instead of a power-of-two multiply for jump-tables
Summary:
SelectionDAGLegalize::ExpandNode() inserts an ISD::MUL when lowering a
BR_JT opcode. While many backends optimize this multiply into a shift, e.g.
the MIPS backend currently always lowers this into a sequence of
load-immediate+multiply+mflo in MipsSETargetLowering::lowerMulDiv().

I initially changed the multiply to a shift in the MIPS backend but it
turns out that would not have handled the MIPSR6 case and was a lot more
code than doing it in LegalizeDAG.
I believe performing this simple optimization in LegalizeDAG instead of
each individual backend is the better solution since this also fixes other
backeds such as MSP430 which calls the multiply runtime function
__mspabi_mpyi without this patch.

Reviewers: sdardis, atanasyan, pftbest, asl

Reviewed By: sdardis

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45760

llvm-svn: 332439
2018-05-16 08:58:26 +00:00
Nirav Dave a87de7d846 [DAGCombine] Move load checks on store of loads into candidate
search. NFCI.

Migrate single-use and non-volatility, non-indexed requirements on
stores of immediate store values to candidate collection pass from
later stage.

llvm-svn: 332392
2018-05-15 20:31:53 +00:00
Sanjay Patel 8652c53d29 [DAG] propagate FMF for all FPMathOperators
This is a simple hack based on what's proposed in D37686, but we can extend it if needed in follow-ups. 
It gets us most of the FMF functionality that we want without adding any state bits to the flags. It 
also intentionally leaves out non-FMF flags (nsw, etc) to minimize the patch.

It should provide a superset of the functionality from D46563 - the extra tests show propagation and 
codegen diffs for fcmp, vecreduce, and FP libcalls.

The PPC log2() test shows the limits of this most basic approach - we only applied 'afn' to the last 
node created for the call. AFAIK, there aren't any libcall optimizations based on the flags currently, 
so that shouldn't make any difference.

Differential Revision: https://reviews.llvm.org/D46854

llvm-svn: 332358
2018-05-15 14:16:24 +00:00
Nicola Zaghen d34e60ca85 Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

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

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

llvm-svn: 332240
2018-05-14 12:53:11 +00:00
Sanjay Patel fe645d295f [DAG] add convenience function to propagate FMF; NFC
There's only one use of this currently, but that could
change with D46563. Either way, we shouldn't have to
update code outside of the flags struct when those
flag definitions change.

llvm-svn: 332155
2018-05-11 23:13:36 +00:00
Sanjay Patel c4e4c5b076 [DAG] clean up flag propagation for binops; NFCI
llvm-svn: 332150
2018-05-11 22:45:22 +00:00
Sanjay Patel 0ddf09a36c [DAG] reduce code duplication; NFCI
llvm-svn: 332133
2018-05-11 20:08:23 +00:00
Vedant Kumar 99d5c072f0 [DAGCombiner] Set the right SDLoc on extended SETCC uses (7/N)
ExtendSetCCUses updates SETCC nodes which use a load (OriginalLoad) to
reflect a simplification to the load (ExtLoad).

Based on my reading, ExtendSetCCUses may create new nodes to extend a
constant attached to a SETCC. It also creates fresh SETCC nodes which
refer to any updated operands.

ISTM that the location applied to the new constant and SETCC nodes
should be the same as the location of the ExtLoad.

This was suggested by Adrian in https://reviews.llvm.org/D45995.

Part of: llvm.org/PR37262

Differential Revision: https://reviews.llvm.org/D46216

llvm-svn: 332119
2018-05-11 18:40:10 +00:00
Vedant Kumar fd340a4047 [DAGCombiner] Set the right SDLoc on a newly-created sextload (6/N)
This teaches tryToFoldExtOfLoad to set the right location on a
newly-created extload. With that in place, the logic for performing a
certain ([s|z]ext (load ...)) combine becomes identical for sexts and
zexts, and we can get rid of one copy of the logic.

The test case churn is due to dependencies on IROrders inherited from
the wrong SDLoc.

Part of: llvm.org/PR37262

Differential Revision: https://reviews.llvm.org/D46158

llvm-svn: 332118
2018-05-11 18:40:08 +00:00
Vedant Kumar f0e5f7c45e [DAGCombiner] Factor out duplicated logic for an extload combine, NFC (5/N)
Part of the logic for combining (zext (load ...)) and (sext (load ...))
is duplicated. This creates problems because bugs in one version have to
be fixed again in the other version.

To address this, as a first step, I've extracted the duplicate logic
into a helper. I'll fix the debug location bug in the helper and
eliminate the copy of its logic in a followup.

Part of: llvm.org/PR37262

Differential Revision: https://reviews.llvm.org/D46157

llvm-svn: 332117
2018-05-11 18:40:02 +00:00
Vedant Kumar e0b5f86b30 [STLExtras] Add distance() for ranges, pred_size(), and succ_size()
This commit adds a wrapper for std::distance() which works with ranges.
As it would be a common case to write `distance(predecessors(BB))`, this
also introduces `pred_size()` and `succ_size()` helpers to make that
easier to write.

Differential Revision: https://reviews.llvm.org/D46668

llvm-svn: 332057
2018-05-10 23:01:54 +00:00
Nirav Dave a5ad417589 [DAG] Avoid using deleted node in rebuildSetCC
Summary:
The combine in rebuildSetCC may be combined to another
node leaving our references stale. Keep a handle on
it to avoid stale references.

Fixes PR36602.

Reviewers: dbabokin, RKSimon, eli.friedman, davide

Subscribers: hiraditya, uabelho, JesperAntonsson, qcolombet, llvm-commits

Differential Revision: https://reviews.llvm.org/D46404

llvm-svn: 331985
2018-05-10 14:28:54 +00:00
Craig Topper 176ec8506f [DAGCombiner] In visitBITCAST when trying to constant fold the bitcast, only call getBitcast if its an fp->int or int->fp conversion even when before legalize ops.
Previously if !LegalOperations we would blindly call getBitcast and hope that getNode would constant fold it. But if the conversion is between a vector and a scalar, getNode has no simplification.

This means we would just get back the original N. We would then return that N which would make the caller of visitBITCAST think that we used CombineTo and did our own worklist management. This prevents target specific optimizations from being called for vector/scalar bitcasts until after legal operations.

llvm-svn: 331896
2018-05-09 17:14:27 +00:00
Amara Emerson 4e66142f14 [DAGCombine] Change store merge candidates check cut off to 1024.
The previous value of 8192 resulted in severe compile time hits in
some pathological cases.

rdar://39781410

Differential Revision: https://reviews.llvm.org/D46581

llvm-svn: 331888
2018-05-09 15:53:06 +00:00
Shiva Chen cd070cdc94 [DebugInfo] Convert intrinsic llvm.dbg.label to MachineInstr.
In order to convert LLVM IR to MachineInstr, we need a new TargetOpcode,
DBG_LABEL, to ‘lower’ intrinsic llvm.dbg.label. The patch
creates this new TargetOpcode and convert intrinsic llvm.dbg.label to
MachineInstr through SelectionDAG.

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

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

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

Patch by Hsiangkai Wang.

llvm-svn: 331842
2018-05-09 02:41:08 +00:00
Matt Arsenault 1f61c0792c DAG: Use correct shift width type
llvm-svn: 331792
2018-05-08 18:43:05 +00:00
Roman Lebedev 9bd6067db6 [DAGCombiner] Masked merge: enhance handling of 'andn' with immediates
Summary:
Split off from D46031.

The previous patch, D46493, completely disabled unfolding in case of immediates.
But we can do better:
{F6120274} {F6120277}

https://rise4fun.com/Alive/xJS

Reviewers: spatel, craig.topper

Reviewed By: spatel

Subscribers: andreadb, llvm-commits

Differential Revision: https://reviews.llvm.org/D46494

llvm-svn: 331685
2018-05-07 21:52:22 +00:00
Roman Lebedev cc42d08b1d [DagCombiner] Not all 'andn''s work with immediates.
Summary:
Split off from D46031.

In masked merge case, this degrades IPC by decreasing instruction count.
{F6108777}
The next patch should be able to recover and improve this.

This also affects the transform @spatel have added in D27489 / rL289738,
and the test coverage for X86 was missing.
But after i have added it, and looked at the changes in MCA, i'm somewhat confused.
{F6093591} {F6093592} {F6093593}
I'd say this regression is an improvement, since `IPC` increased in that case?

Reviewers: spatel, craig.topper

Reviewed By: spatel

Subscribers: andreadb, llvm-commits, spatel

Differential Revision: https://reviews.llvm.org/D46493

llvm-svn: 331684
2018-05-07 21:52:11 +00:00
Aaron Smith 47589e09dd [SelectionDAG] Transfer DbgValues when casts are optimized in SelectionDAG::getNode
Summary:
getNode optimizes (ext (trunc x)) to x and the dbgvalue node on trunc is lost. The fix calls transferDbgValues to add the dbgvalue to x.

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

Patch by Sejong Oh!

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

Reviewed By: aprantl, vsk

Subscribers: kristof.beyls, JDevlieghere, llvm-commits

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

llvm-svn: 331665
2018-05-07 20:15:50 +00:00
Roman Lebedev cb1af9134a [NFC][DAGCombine] unfoldMaskedMerge(): rename two variables
The current names can be confused with the A and B sides
of the canonical masked merge pattern.

llvm-svn: 331609
2018-05-06 20:02:22 +00:00
Roman Lebedev a3b0b59f54 [DAGCombiner] Masked merge: don't touch "not" xor's.
Summary:
Split off form D46031.

It seems we don't want to transform the pattern if the `xor`'s are actually `not`'s.
In vector case, this breaks `andnpd` / `vandnps` patterns.

That being said, we may want to re-visit this `not` handling, maybe in D46073.

Reviewers: spatel, craig.topper, javed.absar

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46492

llvm-svn: 331595
2018-05-05 15:45:40 +00:00
Roman Lebedev 49ada82fa7 [NFC][DagCombiner] unfoldMaskedMerge(): improve readability.
llvm-svn: 331588
2018-05-05 10:39:54 +00:00
Craig Topper 781aa181ab Fix a bunch of places where operator-> was used directly on the return from dyn_cast.
Inspired by r331508, I did a grep and found these.

Mostly just change from dyn_cast to cast. Some cases also showed a dyn_cast result being converted to bool, so those I changed to isa.

llvm-svn: 331577
2018-05-05 01:57:00 +00:00
Michael Berg 2dcf12ffd4 Mapping SDNode flags to MachineInstr flags
Summary: Providing the glue to map SDNode fast math sub flags to MachineInstr fast math sub flags.

Reviewers: spatel, arsenm, wristow

Reviewed By: spatel

Subscribers: wdng

Differential Revision: https://reviews.llvm.org/D46447

llvm-svn: 331567
2018-05-04 23:41:15 +00:00
Michael Berg 7acc81b744 Fast Math Flag mapping into SDNode
Summary: Adding support for Fast flags in the SDNode to leverage fast math sub flag usage.

Reviewers: spatel, arsenm, jbhateja, hfinkel, escha, qcolombet, echristo, wristow, javed.absar

Reviewed By: spatel

Subscribers: llvm-commits, rampitec, nhaehnle, tstellar, FarhanaAleen, nemanjai, javed.absar, jbhateja, hfinkel, wdng

Differential Revision: https://reviews.llvm.org/D45710

llvm-svn: 331547
2018-05-04 18:48:20 +00:00
Bjorn Pettersson 27a841fe83 [SelectionDAG] Refactor code by adding RegsForValue::getRegsAndSizes(). NFCI
Summary:
Added a helper method in RegsForValue to get a list with
all the <RegNumber, RegSize> pairs that we want to iterate
over in SelectionDAGBuilder::EmitFuncArgumentDbgValue and
in SelectionDAGBuilder::visitIntrinsicCall.

Reviewers: vsk

Reviewed By: vsk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46360

llvm-svn: 331510
2018-05-04 08:50:48 +00:00
Bjorn Pettersson 304877e5ec Reapply "[SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)"
Summary:
This reverts SVN r331441 (reapplies r331337), together with a fix
in to handle an already existing fragment expression in the
dbg.value that must be fragmented due to a split PHI node.

This should solve the problem seen in PR37321, which was the
reason for the revert of r331337.

The situation in PR37321 is that we have a PHI node like this

   %u.sroa = phi i80 [ %u.sroa.x, %if.x ],
                     [ %u.sroa.y, %if.y ],
                     [ %u.sroa.z, %if.z ]

and a dbg.value like this

  call void @llvm.dbg.value(metadata i80 %u.sroa,
                            metadata !13,
                            metadata !DIExpression(DW_OP_LLVM_fragment, 0, 80))

The phi node is split into three 32-bit PHI nodes

  %30:gr32 = PHI %11:gr32, %bb.4, %14:gr32, %bb.5, %27:gr32, %bb.8
  %31:gr32 = PHI %12:gr32, %bb.4, %15:gr32, %bb.5, %28:gr32, %bb.8
  %32:gr32 = PHI %13:gr32, %bb.4, %16:gr32, %bb.5, %29:gr32, %bb.8

but since the original value only is 80 bits we need to adjust the size
of the last fragment expression, and with this patch we get

  DBG_VALUE debug-use %30:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 0, 32)
  DBG_VALUE debug-use %31:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 32, 32)
  DBG_VALUE debug-use %32:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 64, 16)

Reviewers: vsk, aprantl, mstorsjo

Reviewed By: aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46384

llvm-svn: 331464
2018-05-03 17:04:16 +00:00
Piotr Padlewski 5dde809404 Rename invariant.group.barrier to launder.invariant.group
Summary:
This is one of the initial commit of "RFC: Devirtualization v2" proposal:
https://docs.google.com/document/d/16GVtCpzK8sIHNc2qZz6RN8amICNBtvjWUod2SujZVEo/edit?usp=sharing

Reviewers: rsmith, amharc, kuhar, sanjoy

Subscribers: arsenm, nhaehnle, javed.absar, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45111

llvm-svn: 331448
2018-05-03 11:03:01 +00:00
Martin Storsjo 67fdea490d Revert "[SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)"
This reverts SVN r331337, see PR37321 for details on the regression
it introduced.

llvm-svn: 331441
2018-05-03 07:09:33 +00:00
Bjorn Pettersson 1c5a05f32c [SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)
Summary:
This is a follow up to rL331182. A PHI node can be split up into
several MIR PHI nodes when being selected. When there is a
dbg.value intrinsic that uses the result of such a PHI node we
need to select several DBG_VALUE instructions, with fragment
expressions, in order to do a correct selection.

Reviewers: rnk, aprantl, vsk

Reviewed By: vsk

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

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D46329

llvm-svn: 331337
2018-05-02 06:56:38 +00:00
Vedant Kumar e23173b677 [DAGCombiner] Fix SDLoc in a (zext (zextload x)) combine (4/N)
The logic for this combine is almost identical to the logic for a
(sext (sextload x)) combine.

This commit factors out the logic so it can be shared by both combines,
and corrects the SDLoc assigned in the zext version of the combine.

Prior to this patch, for the given test case, we would apply the
location associated with the udiv instruction to instructions which
perform the load.

Part of: llvm.org/PR37262

llvm-svn: 331303
2018-05-01 19:51:15 +00:00
Vedant Kumar d7117ed0f9 [DAGCombiner] Fix SDLoc in a (sext (sextload x)) combine (3/N)
Prior to this patch, for the given test case, we would apply the
location associated with the sdiv instruction to instructions which
perform the load.

Part of: llvm.org/PR37262.

Differential Revision: https://reviews.llvm.org/D46222

llvm-svn: 331302
2018-05-01 19:51:15 +00:00
Vedant Kumar cc7b2a55c2 [DAGCombiner] Change the SDLoc on split extloads (2/N)
In DAGCombiner, we try to simplify this pattern:

  ([s|z]ext (load ...))

Conceptually, a new extload which is created while splitting the load
should have the same debug location as the load.

Making this change affects the IROrder of the new load, causing some
test case churn.

In practice, the new location is never different from the location of
the [s|z]ext, at least not during check-llvm or a stage2 build.

Part of: llvm.org/PR37262

Differential Revision: https://reviews.llvm.org/D46156

llvm-svn: 331301
2018-05-01 19:29:15 +00:00
Vedant Kumar ee4bfcaa5a [DAGCombiner] Set the right SDLoc on a newly-created zextload (1/N)
Setting the right SDLoc on a newly-created zextload fixes a line table
bug which resulted in non-linear stepping behavior.

Several backend tests contained CHECK lines which relied on the IROrder
inherited from the wrong SDLoc. This patch breaks that dependence where
feasbile and regenerates test cases where not.

In some cases, changing a node's IROrder may alter register allocation
and spill behavior. This can affect performance. I have chosen not to
prevent this by applying a "known good" IROrder to SDLocs, as this may
hide a more general bug in the scheduler, or cause regressions on other
test inputs.

rdar://33755881, Part of: llvm.org/PR37262

Differential Revision: https://reviews.llvm.org/D45995

llvm-svn: 331300
2018-05-01 19:26:15 +00:00
Adrian Prantl 5f8f34e459 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

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

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

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
Sanjay Patel 1babf5ff32 [DAGCombiner] rename function attribute for disabling ftrunc transform
This is the matching name change for the Clang patch at:
D46236
rL331209

Differential Revision: https://reviews.llvm.org/D46237 

llvm-svn: 331210
2018-04-30 18:20:33 +00:00
Nico Weber 432a38838d IWYU for llvm-config.h in llvm, additions.
See r331124 for how I made a list of files missing the include.
I then ran this Python script:

    for f in open('filelist.txt'):
        f = f.strip()
        fl = open(f).readlines()

        found = False
        for i in xrange(len(fl)):
            p = '#include "llvm/'
            if not fl[i].startswith(p):
                continue
            if fl[i][len(p):] > 'Config':
                fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
                found = True
                break
        if not found:
            print 'not found', f
        else:
            open(f, 'w').write(''.join(fl))

and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.

No intended behavior change.

llvm-svn: 331184
2018-04-30 14:59:11 +00:00
Bjorn Pettersson abafca619b [SelectionDAG] Improve selection of DBG_VALUE using a PHI node result
Summary:
When building the selection DAG at ISel all PHI nodes are
selected and lowered to Machine Instruction PHI nodes before
we start to create any SDNodes. So there are no SDNodes for
values produced by the PHI nodes.

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

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

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

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

Reviewers: #debug-info, aprantl

Reviewed By: #debug-info, aprantl

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

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

llvm-svn: 331182
2018-04-30 14:37:39 +00:00
Heejin Ahn d20d0648ed [DAGCombiner] Fix a case of 1 in non-splat vector pow2 divisor
Summary:
D42479 (rL329525) enabled SDIV combine for pow2 non-splat vector
dividers. But when there is a 1 in a vector, the instruction sequence to
be generated involves shifting a value by the number of its bit widths,
which is undefined
(c64f4dbfe3/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (L6000-L6006)).

Especially, in architectures that do not support vector instructions,
each of element in a vector will be computed separately using scalar
operations, and then the resulting value will be undef for '1' values
in a vector.

(All 1's vector is fine; only vectors mixed with 1 and others will be
affected.)

Reviewers: RKSimon, jgravelle-google

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

Differential Revision: https://reviews.llvm.org/D46161

llvm-svn: 331092
2018-04-27 22:23:11 +00:00
Reid Kleckner efc0f8cbdc [FastISel] Actually enable local value sinking by default
llvm-svn: 331088
2018-04-27 21:51:25 +00:00
Reid Kleckner a28e767f06 [FastISel] Fix local value sinking algorithmic complexity
Now local value sinking only scans and numbers instructions added
between the current flush point and the last flush point. This ensures
that ISel is overall linear in the size of the BB.

Fixes PR37010 and re-enables local value sinking by default.

llvm-svn: 331087
2018-04-27 21:48:51 +00:00
Matt Arsenault 540512c297 DAG: Fix not legalizing vector fcanonicalizes
If an fcanoncialize was done on a vector type that was legal,

llvm-svn: 330981
2018-04-26 19:21:37 +00:00
Sanjay Patel 5a90285bd9 [DAGCombiner] limit ftrunc optimizations with function attribute
As noted, the attribute name is subject to change once we have
the clang side implemented, but it's clear that we need some
kind of attribute-based predication here based on the discussion
for:
rL330437

llvm-svn: 330951
2018-04-26 16:04:44 +00:00
Sanjay Patel a5da086386 [DAGCombiner] refactor FP->int->FP folds; NFC
As discussed in the post-review comments for rL330437,
we need to guard this fold to allow existing code to
keep working with the undefined behavior that they've
come to rely on.

That would mean duplicating more code than we already 
have, so let's fix that first. 

llvm-svn: 330947
2018-04-26 15:20:18 +00:00
Craig Topper f3cefad255 [DAGCombiner][X86] When promoting loads don't use ZEXTLOAD even its legal
We were previously prefering ZEXTLOAD over EXTLOAD if it is legal. This triggers during X86's promotion of i16->i32. Not sure about other targets.

Using ZEXTLOAD can prevent folding it to SEXTLOAD later if we were to promote a sign extended operand like we would need for SRA. However, X86 doesn't currently promote i16 SRA. I was looking into doing that which is how I found this issue.

This is also blocking our ability to fold 4 byte aligned EXTLOADs with "loadi32". This is what caused most of the test changes here.

Differential Revision: https://reviews.llvm.org/D45585#inline-402825

llvm-svn: 330781
2018-04-24 22:35:27 +00:00
Roman Lebedev 95c6eaf530 [DAGCombiner] Unfold scalar masked merge if profitable
Summary:
This is [[ https://bugs.llvm.org/show_bug.cgi?id=37104 | PR37104 ]].

[[ https://bugs.llvm.org/show_bug.cgi?id=6773 | PR6773 ]] will introduce an IR canonicalization that is likely bad for the end assembly.
Previously, `andl`+`andn`/`andps`+`andnps` / `bic`/`bsl` would be generated. (see `@out`)
Now, they would no longer be generated  (see `@in`).
So we need to make sure that they are still generated.

If the mask is constant, we do nothing. InstCombine should have unfolded it.
Else, i use `hasAndNot()` TLI hook.

For now, only handle scalars.

https://rise4fun.com/Alive/bO6

----

I *really* don't like the code i wrote in `DAGCombiner::unfoldMaskedMerge()`.
It is super fragile. Is there something like IR Pattern Matchers for this?

Reviewers: spatel, craig.topper, RKSimon, javed.absar

Reviewed By: spatel

Subscribers: andreadb, courbet, kristof.beyls, javed.absar, rengolin, nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D45733

llvm-svn: 330646
2018-04-23 20:38:49 +00:00
Vedant Kumar f17720633b [SelectionDAG] Dump debug locs in SDNodes
This helps debug issues where selection-dag assigns the wrong location
to an instruction.

Differential Revision: https://reviews.llvm.org/D45913

llvm-svn: 330618
2018-04-23 17:18:24 +00:00
Daniel Neilson 9863b48d4e [SelectionDAG] Refactor lowering of atomic memory intrinsics.
Summary:
This just refactors the lowering of the atomic memory intrinsics to more
closely match the code patterns used in the lowering of the non-atomic
memory intrinsics. Specifically, we encapsulate the lowering in
SelectionDAG::getAtomicMem*() functions rather than embedding
the code directly in the SelectionDAGBuilder code.

llvm-svn: 330603
2018-04-23 15:40:37 +00:00
Sanjay Patel 3d453ad711 [DAGCombine] (float)((int) f) --> ftrunc (PR36617)
This was originally committed at rL328921 and reverted at rL329920 to
investigate failures in Chrome. This time I've added to the ReleaseNotes
to warn users of the potential of exposing UB and let me repeat that
here for more exposure:

  Optimization of floating-point casts is improved. This may cause surprising
  results for code that is relying on undefined behavior. Code sanitizers can
  be used to detect affected patterns such as this:

    int main() {
      float x = 4294967296.0f;
      x = (float)((int)x);
      printf("junk in the ftrunc: %f\n", x);
      return 0;
    }

    $ clang -O1 ftrunc.c -fsanitize=undefined ; ./a.out
    ftrunc.c:5:15: runtime error: 4.29497e+09 is outside the range of 
                   representable values of type 'int'
    junk in the ftrunc: 0.000000


Original commit message:

fptosi / fptoui round towards zero, and that's the same behavior as ISD::FTRUNC,
so replace a pair of casts with the equivalent node. We don't have to account for
special cases (NaN, INF) because out-of-range casts are undefined.

Differential Revision: https://reviews.llvm.org/D44909

llvm-svn: 330437
2018-04-20 15:07:55 +00:00
David Stuttard 31f482c26b [AMDGPU] Fix issues for backend divergence tracking
Summary:
A change to use divergence analysis in the AMDGPU backend was getting formal
arguments incorrect (not tagged as divergent) unless they were VGPR0, VGPR1 or
VGPR2

For graphics shaders it is possible to have more than these passed in as VGPR

Modified the checking code to check for any VGPR registers passed in as formal
arguments.

Also, some intrinsics that are sources of divergence may have been lowered
during instruction selection and are missed on subsequent calls to
isSDNodeSourceOfDivergence - added the relevant AMDGPUISD checks as well.

Finally, the FunctionLoweringInfo tracks virtual registers that are live across
basic block boundaries. This is used to check for divergence of CopyFromRegister
registers using the DivergenceAnalysis analysis. For multiple blocks the lazily
evaluated inverted map VirtReg2Value was not cleared when the ValueMap map was.

Subscribers: arsenm, kzhuravl, wdng, nhaehnle, yaxunl, tpr, t-tye, llvm-commits

Differential Revision: https://reviews.llvm.org/D45372

Change-Id: I112f3bd6dfe0f62e63ce9b43b893982778e4bee3
llvm-svn: 330257
2018-04-18 13:53:31 +00:00
Keith Wyss 3d86823f3d [XRay] Typed event logging intrinsic
Summary:
Add an LLVM intrinsic for type discriminated event logging with XRay.
Similar to the existing intrinsic for custom events, but also accepts
a type tag argument to allow plugins to be aware of different types
and semantically interpret logged events they know about without
choking on those they don't.

Relies on a symbol defined in compiler-rt patch D43668. I may wait
to submit before I can see demo everything working together including
a still to come clang patch.

Reviewers: dberris, pelikan, eizan, rSerge, timshen

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45633

llvm-svn: 330219
2018-04-17 21:30:29 +00:00
Gerolf Hoflehner 5b4a67af1b [DAGCombiner] Fix for oss-fuzz bug
llvm-svn: 330178
2018-04-17 07:22:34 +00:00
Craig Topper 4e644b38d7 [X86] Use APInt::isSubsetof instead of APInt::intersects to avoid a negation of an APInt value. NFC
llvm-svn: 330105
2018-04-15 19:11:25 +00:00
Roman Lebedev 9792838905 [SelectionDAG][NFC] haveNoCommonBitsSet(): add FIXME notes
As suggested in https://reviews.llvm.org/D45631#1068338

llvm-svn: 330102
2018-04-15 18:59:38 +00:00
Sanjay Patel 6c3af659a2 [DAGCombiner, PowerPC] allow X - (fpext(-Y) --> X + fpext(Y) with multiple uses
This is a transform that I limited in instcombine in rL329821 because it was 
creating more instructions in IR when the cast has multiple uses.

But if the cast is free, then we can do the transform regardless of other
uses because it improves the potential throughput of the calculation by
removing a dependency on the fneg.

Differential Revision: https://reviews.llvm.org/D45598

llvm-svn: 330098
2018-04-15 16:43:48 +00:00
Sanjay Patel a54e7d1a6d [DAGCombiner] simplify code; NFC
llvm-svn: 329964
2018-04-12 22:14:58 +00:00
Sanjay Patel 5ace2b765a revert r328921 - [DAGCombine] (float)((int) f) --> ftrunc (PR36617)
This change is exposing UB in source code - as was warned/predicted. :)
See D44909 for discussion. Reverting while we figure out how to fix things.

llvm-svn: 329920
2018-04-12 15:27:01 +00:00
Francis Visoiu Mistrih 3c0d61b7c0 [CodeGen] Allow printing MachineMemOperands with less context in SDAGDumper
Don't assume SelectionDAG is non-null as the targets can use it with a
null pointer.

Differential Revision: https://reviews.llvm.org/D44611

llvm-svn: 329908
2018-04-12 12:59:50 +00:00
Craig Topper 46300d1ff6 [LegalizeTypes] Remove unnecessary type action check on the type of operand 0 when promoting shift result type. NFC
Operand 0 should have the same type of the result. So if the result type needs to be promoted, operand 0 needs to be promoted unconditionally.

llvm-svn: 329883
2018-04-12 06:51:58 +00:00
Reid Kleckner 0828699488 [FastISel] Disable local value sinking by default
This is causing compilation timeouts on code with long sequences of
local values and calls (i.e. foo(1); foo(2); foo(3); ...).  It turns out
that code coverage instrumentation is a great way to create sequences
like this, which how our users ran into the issue in practice.

Intel has a tool that detects these kinds of non-linear compile time
issues, and Andy Kaylor reported it as PR37010.

The current sinking code scans the whole basic block once per local
value sink, which happens before emitting each call. In theory, local
values should only be introduced to be used by instructions between the
current flush point and the last flush point, so we should only need to
scan those instructions.

llvm-svn: 329822
2018-04-11 16:03:07 +00:00
Sam Parker 1f4f4d9a08 [DAGCombine] Improve ReduceLoad for SRL
Recommitting r329283, third time lucky...

If the SRL node is only used by an AND, we may be able to set the
ExtVT to the width of the mask, making the AND redundant. To support
this, another check has been added in isLegalNarrowLoad which queries
whether the load is valid.

Differential Revision: https://reviews.llvm.org/D41350

llvm-svn: 329551
2018-04-09 08:16:11 +00:00
Zvi Rackover 7a53f169f1 DAGCombiner: Combine SDIV with non-splat vector pow2 divisor
Summary:
Extend existing SDIV combine for pow2 constant divider to handle
non-splat vectors of pow2 constants.

Reviewers: RKSimon, craig.topper, spatel, hfinkel, efriedma

Reviewed By: RKSimon

Subscribers: magabari, llvm-commits

Differential Revision: https://reviews.llvm.org/D42479

llvm-svn: 329525
2018-04-08 11:35:20 +00:00
Guozhi Wei 0eb86c8efc [DAGCombiner] Fold (zext (and/or/xor (shl/shr (load x), cst), cst))
In our real world application, we found the following optimization is missed in DAGCombiner

(zext (and/or/xor (shl/shr (load x), cst), cst)) -> (and/or/xor (shl/shr (zextload x), (zext cst)), (zext cst))

If the user of original zext is an add, it may enable further lea optimization on x86.

This patch add a new function CombineZExtLogicopShiftLoad to do this optimization.

Differential Revision: https://reviews.llvm.org/D44402

llvm-svn: 329516
2018-04-07 23:36:10 +00:00
Craig Topper 5b95eae1c3 [DAGCombiner] Add a combine to turn a build vector of zero extends of extract vector elts into a vector zero extend and possibly an extract subvector.
llvm-svn: 329509
2018-04-07 19:09:50 +00:00
Mandeep Singh Grang e92f0cfe34 [CodeGen] Change std::sort to llvm::sort in response to r327219
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

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

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

Reviewers: bogner, rnk, MatzeB, RKSimon

Reviewed By: rnk

Subscribers: JDevlieghere, javed.absar, llvm-commits

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

llvm-svn: 329435
2018-04-06 18:08:42 +00:00
Sam Parker 0e7deb8104 [DAGCombine] Revert r329160
Again, broke the big endian stage 2 builders.

llvm-svn: 329283
2018-04-05 13:46:17 +00:00
Sam Parker 7ec722d603 [DAGCombine] Improve ReduceLoadWidth for SRL
Recommitting rL321259. Previosuly this caused an issue with PPCBE but
I didn't receieve a reproducer and didn't have the time to follow up.
If the issue appears again, please provide a reproducer so I can fix
it.

Original commit message:

If the SRL node is only used by an AND, we may be able to set the
ExtVT to the width of the mask, making the AND redundant. To support
this, another check has been added in isLegalNarrowLoad which queries
whether the load is valid.

Differential Revision: https://reviews.llvm.org/D41350

llvm-svn: 329160
2018-04-04 09:26:56 +00:00
Sanjay Patel 6124cae8f7 [DAGCombine] (float)((int) f) --> ftrunc (PR36617)
fptosi / fptoui round towards zero, and that's the same behavior as ISD::FTRUNC, 
so replace a pair of casts with the equivalent node. We don't have to account for 
special cases (NaN, INF) because out-of-range casts are undefined.

Differential Revision: https://reviews.llvm.org/D44909

llvm-svn: 328921
2018-03-31 17:55:44 +00:00
Fangrui Song 956ee79795 Fix a bunch of typoes. NFC
llvm-svn: 328907
2018-03-30 22:22:31 +00:00
Sanjay Patel e09b7dcf3d [SelectionDAG] Removing FABS folding from DAGCombiner
The code has bugs dealing with -0.0.

Since D44550 introduced FABS pattern folding in InstCombine, 
this patch removes the now-redundant code that causes 
https://bugs.llvm.org/show_bug.cgi?id=36600.

Patch by Mikhail Dvoretckii!

Differential Revision: https://reviews.llvm.org/D44683

llvm-svn: 328872
2018-03-30 15:42:52 +00:00
Craig Topper 2fa1436206 [IR][CodeGen] Remove dependency on EVT from IR/Function.cpp. Move EVT to CodeGen layer.
Currently EVT is in the IR layer only because of Function.cpp needing a very small piece of the functionality of EVT::getEVTString(). The rest of EVT is used in codegen making CodeGen a better place for it.

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

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

llvm-svn: 328806
2018-03-29 17:21:10 +00:00
Pirama Arumuga Nainar ddd7b06842 Remap values in PromotedFloats
Summary: When a node is about to be erased from ReplacedValues, we should also remap its corresponding values in PromotedFloats.

Patch by Yan Luo (Yan.Luo2@synopsys.com)

Reviewers: pirama

Reviewed By: pirama

Subscribers: lebedev.ri, llvm-commits

Differential Revision: https://reviews.llvm.org/D44872

llvm-svn: 328644
2018-03-27 17:42:36 +00:00
David Blaikie 36a0f226b1 Fix layering by moving ValueTypes.h from CodeGen to IR
ValueTypes.h is implemented in IR already.

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

llvm-svn: 328395
2018-03-23 23:58:25 +00:00
David Blaikie 6054e650ff Move TargetLoweringObjectFile from CodeGen to Target to fix layering
It's implemented in Target & include from other Target headers, so the
header should be in Target.

llvm-svn: 328392
2018-03-23 23:58:19 +00:00
Martin Storsjo db75aa96d3 Revert "[DAGCombiner] Fold (zext (and/or/xor (shl/shr (load x), cst), cst))"
This reverts commit r328252. This change broke building a number
of projects when targeting ARM and AArch64, see PR36873.

llvm-svn: 328297
2018-03-23 08:36:47 +00:00
Nirav Dave 5b3e8791b4 [DAG] Fix node id invalidation in Instruction Selection.
Invalidation should be bit negation. Add missing negation.

llvm-svn: 328287
2018-03-23 01:22:39 +00:00
Guozhi Wei 17ff975eb1 [DAGCombiner] Fold (zext (and/or/xor (shl/shr (load x), cst), cst))
In our real world application, we found the following optimization is missed in DAGCombiner

(zext (and/or/xor (shl/shr (load x), cst), cst)) -> (and/or/xor (shl/shr (zextload x), (zext cst)), (zext cst))

If the user of original zext is an add, it may enable further lea optimization on x86.

This patch add a new function CombineZExtLogicopShiftLoad to do this optimization.

Differential Revision: https://reviews.llvm.org/D44402

llvm-svn: 328252
2018-03-22 21:47:25 +00:00
Nirav Dave 8c5f47ac40 [DAG, X86] Fix ISel-time node insertion ids
As in SystemZ backend, correctly propagate node ids when inserting new
unselected nodes into the DAG during instruction Seleciton for X86
target.

Fixes PR36865.

Reviewers: jyknight, craig.topper

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D44797

llvm-svn: 328233
2018-03-22 19:32:07 +00:00
Bjorn Pettersson 5c25f88536 [SelectionDAG] Support multiple dangling debug info for one value
Summary:
When building the selection DAG we sometimes need to postpone
the handling of a dbg.value until the value it should refer to
is created. This is done by using the DanglingDebugInfoMap.
In the past this map has been limited to hold one dangling
dbg.value per value. This patch removes that restriction.

Reviewers: aprantl, rnk, probinson, vsk

Reviewed By: aprantl

Subscribers: Ka-Ka, llvm-commits, JDevlieghere

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D44610

llvm-svn: 328084
2018-03-21 09:44:34 +00:00
Craig Topper c2dbd677bd [PowerPC][LegalizeFloatTypes] Move the PPC hacks for (i32 fp_to_sint/fp_to_uint (ppcf128 X)) out of LegalizeFloatTypes and into PPC specific code
I'm not entirely sure these hacks are still needed. If you remove the hacks completely, the name of the library call that gets generated doesn't match the grep the test previously had. So the test wasn't really checking anything.

If the hack is still needed it belongs in PPC specific code. I believe the FP_TO_SINT code here is the only place in the tree where a FP_ROUND_INREG node is created today. And I don't think its even being used correctly because the legalization returned a BUILD_PAIR with the same value twice. That doesn't seem right to me. By moving the code entirely to PPC we can avoid creating the FP_ROUND_INREG at all.

I replaced the grep in the existing test with full checks generated by hacking update_llc_test_check.py to support ppc32 just long enough to generate it.

Differential Revision: https://reviews.llvm.org/D44061

llvm-svn: 328017
2018-03-20 18:49:28 +00:00
Aaron Smith 6738960588 [SelectionDAG] Transfer DbgValues when integer operations are promoted
Summary:
DbgValue nodes were not transferred when integer DAG nodes were promoted. For example, if an i32 add node was promoted to an i64 add node by DAGTypeLegalizer::PromoteIntegerResult(), its DbgValue node was not transferred to the new node. The simple fix is to update SetPromotedInteger() to transfer DbgValues. 

Add AArch64/dbg-value-i8.ll to test this change and fix ARM/debug-info-d16-reg.ll which had the wrong DILocalVariable nodes with arg numbers even though they are not for function parameters.

Patch by Se Jong Oh!

Reviewers: vsk, JDevlieghere, aprantl

Reviewed By: JDevlieghere

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

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D44546

llvm-svn: 327919
2018-03-19 22:58:50 +00:00
Craig Topper 956fec2a4a [DAGCombiner] Fix type in comment. NFC
llvm-svn: 327916
2018-03-19 22:25:26 +00:00
Nirav Dave 3264c1bdf6 [DAG, X86] Revert r327197 "Revert r327170, r327171, r327172"
Reland ISel cycle checking improvements after simplifying node id
invariant traversal and correcting typo.

llvm-svn: 327898
2018-03-19 20:19:46 +00:00
Nirav Dave 5f0ab71b62 Revert "[DAG, X86] Revert r327197 "Revert r327170, r327171, r327172""
as it times out building test-suite on PPC.

llvm-svn: 327778
2018-03-17 19:24:54 +00:00
Nirav Dave 982d3a56ea [DAG, X86] Revert r327197 "Revert r327170, r327171, r327172"
Reland ISel cycle checking improvements after simplifying and reducing
node id invariant traversal.

llvm-svn: 327777
2018-03-17 17:42:10 +00:00
Oren Ben Simhon fdd72fd522 [X86] Added support for nocf_check attribute for indirect Branch Tracking
X86 Supports Indirect Branch Tracking (IBT) as part of Control-Flow Enforcement Technology (CET).
IBT instruments ENDBR instructions used to specify valid targets of indirect call / jmp.
The `nocf_check` attribute has two roles in the context of X86 IBT technology:
	1. Appertains to a function - do not add ENDBR instruction at the beginning of the function.
	2. Appertains to a function pointer - do not track the target function of this pointer by adding nocf_check prefix to the indirect-call instruction.

This patch implements `nocf_check` context for Indirect Branch Tracking.
It also auto generates `nocf_check` prefixes before indirect branchs to jump tables that are guarded by range checks.

Differential Revision: https://reviews.llvm.org/D41879

llvm-svn: 327767
2018-03-17 13:29:46 +00:00
Jonas Paulsson e9f7fa83d5 [SelectionDAG] Handle big endian target BITCAST in computeKnownBits()
The BITCAST handling in computeKnownBits() previously only worked for little
endian.

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

SystemZ test case.

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

llvm-svn: 327764
2018-03-17 08:04:00 +00:00
Craig Topper 1b8cf49704 [SelectionDAG][ARM][X86] Teach PromoteIntRes_SETCC to do a better job picking the result type for the setcc.
Previously if getSetccResultType returned an illegal type we just fell back to using the default promoted type. This appears to have been to handle the case where for vectors getSetccResultType returns the input type, but the input type itself isn't legal and will need to be promoted. Without the legality check we would never reach a legal type.

But just picking the promoted type to be the setcc type can create strange setccs where the result type is 128 bits and the operand type is 256 bits. If for example the result type was promoted to v8i16 from v8i1, but the input type was promoted from v8i23 to v8i32. We currently handle this with custom lowering code in X86.

This legality check also caused us reject the getSetccResultType when the input type needed to be widened or split. Even though that result wouldn't have caused legalization to get stuck.

This patch tries to fix this by detecting the getSetccResultType needs to be promoted. If its input type also needs to be promoted we'll try a ask for a new setcc result type based on its eventual promoted value. Otherwise we fall back to default type to promote to.

For any other illegal values we might get back from the initial call to getSetccResultType we just keep and allow it to be re-legalized later via splitting or widening or scalarizing.

llvm-svn: 327683
2018-03-15 23:04:11 +00:00
Reid Kleckner 3a7a2e4a0a [FastISel] Sink local value materializations to first use
Summary:
Local values are constants, global addresses, and stack addresses that
can't be folded into the instruction that uses them. For example, when
storing the address of a global variable into memory, we need to
materialize that address into a register.

FastISel doesn't want to materialize any given local value more than
once, so it generates all local value materialization code at
EmitStartPt, which always dominates the current insertion point. This
allows it to maintain a map of local value registers, and it knows that
the local value area will always dominate the current insertion point.

The downside is that local value instructions are always emitted without
a source location. This is done to prevent jumpy line tables, but it
means that the local value area will be considered part of the previous
statement. Consider this C code:
  call1();      // line 1
  ++global;     // line 2
  ++global;     // line 3
  call2(&global, &local); // line 4

Today we end up with assembly and line tables like this:
  .loc 1 1
  callq call1
  leaq global(%rip), %rdi
  leaq local(%rsp), %rsi
  .loc 1 2
  addq $1, global(%rip)
  .loc 1 3
  addq $1, global(%rip)
  .loc 1 4
  callq call2

The LEA instructions in the local value area have no source location and
are treated as being on line 1. Stepping through the code in a debugger
and correlating it with the assembly won't make much sense, because
these materializations are only required for line 4.

This is actually problematic for the VS debugger "set next statement"
feature, which effectively assumes that there are no registers live
across statement boundaries. By sinking the local value code into the
statement and fixing up the source location, we can make that feature
work. This was filed as https://bugs.llvm.org/show_bug.cgi?id=35975 and
https://crbug.com/793819.

This change is obviously not enough to make this feature work reliably
in all cases, but I felt that it was worth doing anyway because it
usually generates smaller, more comprehensible -O0 code. I measured a
0.12% regression in code generation time with LLC on the sqlite3
amalgamation, so I think this is worth doing.

There are some special cases worth calling out in the commit message:
1. local values materialized for phis
2. local values used by no-op casts
3. dead local value code

Local values can be materialized for phis, and this does not show up as
a vreg use in MachineRegisterInfo. In this case, if there are no other
uses, this patch sinks the value to the first terminator, EH label, or
the end of the BB if nothing else exists.

Local values may also be used by no-op casts, which adds the register to
the RegFixups table. Without reversing the RegFixups map direction, we
don't have enough information to sink these instructions.

Lastly, if the local value register has no other uses, we can delete it.
This comes up when fastisel tries two instruction selection approaches
and the first materializes the value but fails and the second succeeds
without using the local value.

Reviewers: aprantl, dblaikie, qcolombet, MatzeB, vsk, echristo

Subscribers: dotdash, chandlerc, hans, sdardis, amccarth, javed.absar, zturner, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D43093

llvm-svn: 327581
2018-03-14 21:54:21 +00:00
Francis Visoiu Mistrih e85b06d65f [CodeGen] Use MIR syntax for MachineMemOperand printing
Get rid of the "; mem:" suffix and use the one we use in MIR: ":: (load 2)".

rdar://38163529

Differential Revision: https://reviews.llvm.org/D42377

llvm-svn: 327580
2018-03-14 21:52:13 +00:00
Craig Topper b36cb20ef9 [X86] Teach X86TargetLowering::targetShrinkDemandedConstant to set non-demanded bits if it helps created an and mask that can be matched as a zero extend.
I had to modify the bswap recognition to allow unshrunk masks to make this work.

Fixes PR36689.

Differential Revision: https://reviews.llvm.org/D44442

llvm-svn: 327530
2018-03-14 16:55:15 +00:00
Craig Topper 4aeec51986 [DAGCombiner] Allow visitEXTRACT_SUBVECTOR to combine with BUILD_VECTORS between LegalizeVectorOps and LegalizeDAG.
BUILD_VECTORs aren't themselves legalized until LegalizeDAG so we should still be able to create an "illegal" one before that. This helps combine with BUILD_VECTORS that are introduced during LegalizeVectorOps due to unrolling.

llvm-svn: 327446
2018-03-13 20:36:28 +00:00
Simon Pilgrim 9855b39380 [DAGCombine] visitREM - Don't assume that one divrem isn't driving another
Under some circumstances the divrems won't have been combined together before getting to this code.

So replace the assertion with a if() guard to not expand to X-((X/C)*C) to give the other combine chance to happen.

Reduced from OSS-Fuzz #6883
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=6883

llvm-svn: 327424
2018-03-13 17:17:15 +00:00
Daniel Neilson 5182113f07 [SelectionDAGBuilder] Replace deprecated calls to MemoryIntrinsic::getAlignment() (NFCI)
Summary:
This change is part of step five in the series of changes to remove alignment argument from
memcpy/memmove/memset in favour of alignment attributes. In particular, this changes the
SelectionDAGBuilder to cease using the old getAlignment() API of MemoryIntrinsic in favour of getting
source & dest specific alignments through the new API.

Steps:
Step 1) Remove alignment parameter and create alignment parameter attributes for
memcpy/memmove/memset. ( rL322965, rC322964, rL322963 )
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
source and dest alignments. ( rL323597 )
Step 3) Update Clang to use the new IRBuilder API. ( rC323617 )
Step 4) Update Polly to use the new IRBuilder API. ( rL323618 )
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
and those that use use MemIntrinsicInst::[get|set]Alignment() to use [get|set]DestAlignment()
and [get|set]SourceAlignment() instead. ( rL323886, rL323891, rL324148, rL324273, rL324278,
rL324384, rL324395, rL324402, rL324626, rL324642, rL324653, rL324654, rL324773, rL324774,
rL324781, rL324784, rL324955, rL324960, rL325816, rL327398 )
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
MemIntrinsicInst::[get|set]Alignment() methods.

Reference
   http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.html
   http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

llvm-svn: 327421
2018-03-13 16:31:19 +00:00
Craig Topper 80058e30cc [LegalizeTypes] In SplitVecOp_TruncateHelper, use GetSplitVector on the input instead of creating new extract_subvectors.
llvm-svn: 327355
2018-03-13 01:17:40 +00:00
Bjorn Pettersson a223f815dd [SelectionDAG] Improve handling of dangling debug info
Summary:
1) Make sure to discard dangling debug info if the variable (or
variable fragment) is mapped to something new before we had a
chance to resolve the dangling debug info.

2) When resolving debug info, make sure to bump the associated
SDNodeOrder to ensure that the DBG_VALUE is emitted after the
instruction that defines the value used in the DBG_VALUE.
This will avoid a debug-use before def scenario as seen in
https://bugs.llvm.org/show_bug.cgi?id=36417.

The new test case, test/DebugInfo/X86/sdag-dangling-dbgvalue.ll,
show some other limitations in how dangling debug info is
handled in the SelectionDAG. Since we currently only support
having one dangling dbg.value per Value, we will end up dropping
debug info when there are more than one variable that is described
by the same "dangling value".

Reviewers: aprantl

Reviewed By: aprantl

Subscribers: aprantl, eraman, llvm-commits, JDevlieghere

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D44369

llvm-svn: 327303
2018-03-12 18:02:39 +00:00
Nirav Dave 042678bd55 Revert: r327172 "Correct load-op-store cycle detection analysis"
r327171 "Improve Dependency analysis when doing multi-node Instruction Selection"
        r328170 "[DAG] Enforce stricter NodeId invariant during Instruction selection"

Reverting patch as NodeId invariant change is causing pathological
increases in compile time on PPC

llvm-svn: 327197
2018-03-10 02:16:15 +00:00
Craig Topper 508a5b2466 [TargetLowering] Remove redundant term in two ifs in SimplifySetCC. NFC
If we get into the right hand side of the OR, we know that isOpaque is true since the left hand size is just a check that it's false.

llvm-svn: 327179
2018-03-09 22:24:12 +00:00
Nirav Dave d668f69ee7 Improve Dependency analysis when doing multi-node Instruction Selection
Relanding after fixing NodeId Invariant.

Cleanup cycle/validity checks in ISel (IsLegalToFold,
HandleMergeInputChains) and X86 (isFusableLoadOpStore). Now do a full
search for cycles / dependencies pruning the search when topological
property of NodeId allows.

As part of this propogate the NodeId-based cutoffs to narrow
hasPreprocessorHelper searches.

Reviewers: craig.topper, bogner

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D41293

llvm-svn: 327171
2018-03-09 20:57:42 +00:00
Nirav Dave 071699bf82 [DAG] Enforce stricter NodeId invariant during Instruction selection
Instruction Selection makes use of the topological ordering of nodes
by node id (a node's operands have smaller node id than it) when doing
cycle detection.  During selection we may violate this property as a
selection of multiple nodes may induce a use dependence (and thus a
node id restriction) between two unrelated nodes. If a selected node
has an unselected successor this may allow us to miss a cycle in
detection an invalid selection.

This patch fixes this by marking all unselected successors of a
selected node have negated node id.  We avoid pruning on such negative
ids but still can reconstruct the original id for pruning.

In-tree targets have been updated to replace DAG-level replacements
with ISel-level ones which enforce this property.

This preemptively fixes PR36312 before triggering commit r324359 relands

Reviewers: craig.topper, bogner, jyknight

Subscribers: arsenm, nhaehnle, javed.absar, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D43198

llvm-svn: 327170
2018-03-09 20:57:15 +00:00
Nirav Dave 775f07d121 Make early exit hasPredecessorHelper return true. NFCI.
All uses conservatively assume in early exit case that it will be a
predecessor. Changing default removes checking code in all uses.

llvm-svn: 327169
2018-03-09 20:56:51 +00:00
Peter Collingbourne 2974856ad4 Use branch funnels for virtual calls when retpoline mitigation is enabled.
The retpoline mitigation for variant 2 of CVE-2017-5715 inhibits the
branch predictor, and as a result it can lead to a measurable loss of
performance. We can reduce the performance impact of retpolined virtual
calls by replacing them with a special construct known as a branch
funnel, which is an instruction sequence that implements virtual calls
to a set of known targets using a binary tree of direct branches. This
allows the processor to speculately execute valid implementations of the
virtual function without allowing for speculative execution of of calls
to arbitrary addresses.

This patch extends the whole-program devirtualization pass to replace
certain virtual calls with calls to branch funnels, which are
represented using a new llvm.icall.jumptable intrinsic. It also extends
the LowerTypeTests pass to recognize the new intrinsic, generate code
for the branch funnels (x86_64 only for now) and lay out virtual tables
as required for each branch funnel.

The implementation supports full LTO as well as ThinLTO, and extends the
ThinLTO summary format used for whole-program devirtualization to
support branch funnels.

For more details see RFC:
http://lists.llvm.org/pipermail/llvm-dev/2018-January/120672.html

Differential Revision: https://reviews.llvm.org/D42453

llvm-svn: 327163
2018-03-09 19:11:44 +00:00
Sebastian Pop b4bd0a404f [x86][aarch64] ask the backend whether it has a vector blend instruction
The code to match and produce more x86 vector blends was enabled for all
architectures even though the transform may pessimize the code for other
architectures that do not provide a vector blend instruction.

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

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

llvm-svn: 327132
2018-03-09 14:29:21 +00:00
Sameer AbuAsal 986865c090 Propagate flags to SDValue in SplitVecOp_VECREDUCE
This patch is a fix for PR36642.

 While legalizing long vector types, make sure the smaller types get the
 flags of the wider type.

 bugzilla link: https://bugs.llvm.org/show_bug.cgi?id=36642

Change-Id: I0c2829639f094c862c10a6b51b342d4c2563e1fa
llvm-svn: 327079
2018-03-08 23:41:40 +00:00
Craig Topper 3d2af5038a [TargetLowering] Remove redundant if condition in SimplifySetcc. NFC
We were checking the condition code a second time when we were already in a block with this same condition code check.

llvm-svn: 327069
2018-03-08 21:53:36 +00:00
Simon Pilgrim ca38c762e4 [TargetLowering] Add vector BITCAST support to SimplifyDemandedVectorElts
Notably helps cleanup after legalization of vector types

Differential Revision: https://reviews.llvm.org/D43674

llvm-svn: 326838
2018-03-06 22:32:01 +00:00
Eric Liu 47f42c2167 Fix an unused variable warning introduced by rr326703. NFC
llvm-svn: 326732
2018-03-05 18:36:39 +00:00
Alexander Timofeev 2e5eeceeb7 Pass Divergence Analysis data to Selection DAG to drive divergence
dependent instruction selection.

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

llvm-svn: 326703
2018-03-05 15:12:21 +00:00
Craig Topper 4196dd12a2 [DAGCombiner] Add a peekThroughBitcast to MergeStoresOfConstantsOrVecElts to fix a crash if we are storing a bitcast of a constant.
Loading a constant into a k-register in AVX512 requires a bitcast from a scalar constant. In the test case here we have a k-register store that gets split into multiple parts of KNL. MergeConsecutiveStores sees each of these pieces as a consecutive store and looks through the bitcast to find the underly scalar constant. But when we went to create the combined store we didn't look through the same bitcast.

llvm-svn: 326677
2018-03-04 18:51:46 +00:00
Craig Topper dbf75c9c79 [LegalizeVectorTypes] When scalarizing the operand of a unary op like TRUNC, use a SCALAR_TO_VECTOR rather than a single element BUILD_VECTOR to convert back to a vector type.
X86 considers v1i1 a legal type under AVX512 and as such a truncate from a v1iX type to v1i1 can be turned into a scalar truncate plus a conversion to v1i1. We would much prefer a v1i1 SCALAR_TO_VECTOR over a one element BUILD_VECTOR.

During lowering we were detecting the v1i1 BUILD_VECTOR as a splat BUILD_VECTOR like we try to do for v2i1/v4i1/etc. In this case we create (select i1 splat_elt, v1i1 all-ones, v1i1 all-zeroes). That goes through some more legalization and we end up with a CMOV choosing between 0 and 1 in scalar and a scalar_to_vector.

Arguably we could detect the v1i1 BUILD_VECTOR and do this better in X86 target code. But just using a SCALAR_TO_VECTOR in legalization is much easier.

llvm-svn: 326637
2018-03-02 23:27:50 +00:00
Adrian Prantl dfe15f36d5 Add DBG_VALUE support to the linear DAG scheduler
The fast/linear DAG scheduler doesn't lower DBG_VALUEs except for
function entry nodes.

Patch by Joshua Cranmer!

Differential Revision: https://reviews.llvm.org/D43028

llvm-svn: 326631
2018-03-02 22:59:51 +00:00
Craig Topper e7ca6f5456 [DAGCombiner] When combining zero_extend of a truncate, only mask before extending for vectors.
Masking first, prevents the extend from being combine with loads. Its also interfering with some vXi1 extraction code.

Differential Revision: https://reviews.llvm.org/D42679

llvm-svn: 326500
2018-03-01 22:32:25 +00:00
Craig Topper eedfbc4ab7 [SelectionDAG] Support some SimplifySetCC cases for comparing against vector splats of constants.
This supports things like

(setcc ugt X, 0) -> (setcc ne X, 0)

I've restricted to only make changes to vectors before legalize ops because I doubt all targets have accurate condition code legality information for vectors given how little we did before.

Differential Revision: https://reviews.llvm.org/D42948

llvm-svn: 326495
2018-03-01 22:15:39 +00:00
Than McIntosh b3d88a7466 [CodeGen] fix argument attribute in lowering statepoint/patchpoint
Summary:
Use the correct loop index varaible, ArgI, to retrieve attributes.

Reviewers: thanm, sanjoy, rnk

Reviewed By: rnk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43832

llvm-svn: 326433
2018-03-01 13:31:57 +00:00
Craig Topper 6df870ca58 [SelectionDAG] Remove code from PromoteIntRes_CONCAT_VECTORS that was added in r320674 to help X86.
AVX512 used to promote v32i1 to v32i8 during legalization when BWI was disabled. So this code was added to improve legalization of v32i1 concat_vectors of v16i1 by extending the v16i1 to v16i8 to avoid scalarization.

X86 has since switched to legalizing v32i1 by splitting to v16i1 instead. This has rendered this code unnecessary and its no longer exercised.

llvm-svn: 326153
2018-02-27 00:07:24 +00:00
Simon Pilgrim 295e8b4e12 [TargetLowering] SimplifyDemandedVectorElts - pass demanded elts through ADD/SUB ops
llvm-svn: 326044
2018-02-24 20:59:14 +00:00
Simon Pilgrim c0dbdb86c3 [TargetLowering] SimplifyDemandedVectorElts - pass demanded elts through TRUNCATE ops
llvm-svn: 326043
2018-02-24 19:28:34 +00:00
Amaury Sechet 893a6b89ff [DAGCOmbine] Ensure that (brcond (setcc ...)) is handled in a canonical manner.
Summary:
There are transformation that change setcc into other constructs, and transform that try to reconstruct a setcc from the brcond condition. Depending on what order these transform are done, the end result differs.

Most of the time, it is preferable to get a setcc as a brcond argument (and this is why brcond try to recreate the setcc in the first place) so we ensure this is done every time by also doing it at the setcc level when the only user is a brcond.

Reviewers: spatel, hfinkel, niravd, craig.topper

Subscribers: nhaehnle, llvm-commits

Differential Revision: https://reviews.llvm.org/D41235

llvm-svn: 325892
2018-02-23 11:50:42 +00:00
Craig Topper a2cc3c055c [TargetLowering] Rename isCondCodeLegal to isCondCodeLegalOrCustom. Add real isCondCodeLegal. Update callers to use one or the other.
isCondCodeLegal internally checked Legal or Custom which is misleading. Though no targets set any cond code action to Custom today.

So I've renamed isCondCodeLegal to isCondCodeLegalOrCustom and added a real isCondCodeLegal that only checks Legal.

I've changed legalization code to use isCondCodeLegalOrCustom and left things reachable via DAG combine as isCondCodeLegal. I've also changed some places that called getCondCodeAction and compared to Legal to just use isCondCodeLegal.

I'm looking at trying to keep SETCC all the way to isel for the AVX512 integer comparisons and I suspect I'll need to make some condition codes Custom to stop DAG combine from changing things post LegalizeOps. Prior to this only Expand stopped DAG combine, but that causes LegalizeOps to try to swap operands or invert rather than calling our Custom handler.

Differential Revision: https://reviews.llvm.org/D43607

llvm-svn: 325829
2018-02-22 20:51:26 +00:00
Sander de Smalen a86f3cfb49 Revert "[DebugInfo][FastISel] Fix dropping dbg.value()"
This patch reverts r325440 and r325438 because it triggers an
assertion in SelectionDAGBuilder.cpp. Also having debug enabled
may unintentionally affect code-gen. The patch is reverted until
we find a better solution.

llvm-svn: 325825
2018-02-22 19:53:59 +00:00
Simon Pilgrim be72fe1fda [SelectionDAG] Move matchUnaryPredicate/matchBinaryPredicate into SelectionDAGNodes.h
This allows us to improve vector constant matching in more DAG code (backends, TargetLowering etc.).

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

llvm-svn: 325815
2018-02-22 18:45:13 +00:00
Craig Topper 1d104b996a [DAGCombiner] Add two calls to isVector before making calls to getVectorElementType/getVectorNumElements to avoid an assert.
We looked through a BITCAST, but the bitcast might be a from a scalar type rather than a vector.

I don't have a test case. I stumbled onto it while prototyping another change that isn't ready yet.

llvm-svn: 325750
2018-02-22 07:05:27 +00:00
Craig Topper 7fbea20b90 [SelectionDAG] Support known true/false SimplifySetCC cases for comparing against vector splats of constants.
This is split off from D42948 and includes just the cases that constant fold to true or false. It also includes some refactoring to keep predicate checks together.

This supports things like

(setcc uge X, 0) -> true

Differential Revision: https://reviews.llvm.org/D43489

llvm-svn: 325627
2018-02-20 21:48:14 +00:00
Craig Topper 35801fa5ce [SelectionDAG] Add LegalTypes flag to getShiftAmountTy. Use it to unify and simplify DAGCombiner and simplifySetCC code and fix a bug.
DAGCombiner and SimplifySetCC both use getPointerTy for shift amounts pre-legalization. DAGCombiner uses a single helper function to hide this. SimplifySetCC does it in multiple places.

This patch adds a defaulted parameter to getShiftAmountTy that can make it return getPointerTy for scalar types. Use this parameter to simplify the SimplifySetCC and DAGCombiner.

Additionally, there were two places in SimplifySetCC that were creating shifts using the target's preferred shift amount pre-legalization. If the target uses a narrow type and the type is illegal, this can cause SimplfiySetCC to create a shift with an amount that can't represent all possible shift values for the type. To fix this we should use pointer type there too.

Alternatively we could make getScalarShiftAmountTy for each target return a safe value for large types as proposed in D43445. And maybe we should still do that, but fixing the SimplifySetCC code keeps other targets from tripping over this in the future.

Fixes PR36250.

Differential Revision: https://reviews.llvm.org/D43449

llvm-svn: 325602
2018-02-20 17:41:05 +00:00
Simon Pilgrim 2f29afb439 [VectorLegalizer] Fix uint64_t typo in ExpandUINT_TO_FLOAT (PR36391)
ExpandUINT_TO_FLOAT can accept vXi32 or vXi64 inputs, so we need to use a uint64_t shift to generate the 2^(BW/2) constant.

No test case unfortunately as no upstream target uses this, but its affecting a downstream target.

llvm-svn: 325578
2018-02-20 13:24:24 +00:00
Simon Pilgrim 70eb508605 [SelectionDAG] ComputeKnownBits - add support for SMIN+SMAX clamp patterns
If we have a clamp pattern, SMIN(SMAX(X, LO),HI) or SMAX(SMIN(X, HI),LO) then we can deduce that the number of signbits (zeros/ones) will be at least the minimum of the LO and HI constants.

ComputeKnownBits equivalent of D43338.

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

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

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

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

llvm-svn: 325450
2018-02-17 22:19:50 +00:00
Simon Pilgrim 8da142bff1 [SelectionDAG] SimplifyDemandedVectorElts - add support for VECTOR_INSERT_ELT
Differential Revision: https://reviews.llvm.org/D43431

llvm-svn: 325449
2018-02-17 21:49:40 +00:00
Sander de Smalen 47952b0c03 [DebugInfo][FastISel] Fix dropping dbg.value()
Summary:
https://llvm.org/PR36263 shows that when compiling at -O0 a dbg.value()
instruction (that remains from an original dbg.declare()) is dropped
by FastISel. Since FastISel selects instructions by iterating a basic
block backwards, it drops the dbg.value if one of its operands is not
yet instantiated by a previously selected instruction.

Instead of calling 'lookUpRegForValue()' we can call 'getRegForValue()'
instead that will insert a placeholder for the operand to be filled in
when continuing the instruction selection.

Reviewers: aprantl, dblaikie, probinson

Reviewed By: aprantl

Subscribers: llvm-commits, dstenb, JDevlieghere

Differential Revision: https://reviews.llvm.org/D43386

llvm-svn: 325438
2018-02-17 16:42:54 +00:00
Simon Pilgrim d6beac3b76 [DAGCombiner] Remove simplifyShuffleMask - now handled more generally by SimplifyDemandedVectorElts.
llvm-svn: 325429
2018-02-17 12:36:56 +00:00
Chandler Carruth a1d6107b14 [DAG, X86] Revert r324797, r324491, and r324359.
Sadly, r324359 caused at least PR36312. There is a patch out for review
but it seems to be taking a bit and we've already had these crashers in
tree for too long. We're hitting this PR in real code now and are
blocked on shipping new compilers as a consequence so I'm reverting us
back to green.

Sorry for the churn due to the stacked changes that I had to revert. =/

llvm-svn: 325420
2018-02-17 02:26:25 +00:00
Simon Pilgrim 1b81064d1e Fix signed/unsigned comparison warning. NFCI.
llvm-svn: 325363
2018-02-16 17:26:59 +00:00
Simon Pilgrim 5d005a359e Fix signed/unsigned comparison warning. NFCI.
llvm-svn: 325359
2018-02-16 16:52:50 +00:00
Simon Pilgrim ff53a4a234 [SelectionDAG] Enable SimplifyDemandedVectorElts support for simplifying shuffle masks
Based off the DemandedElts mask the and UNDEF elements returned from the SimplifyDemandedVectorElts calls to the shuffle operands, we can attempt to simplify the shuffle mask.

I had to be very conservative here as accepting post-legalized shuffle masks could cause problems for targets that legalize UNDEF mask elements back to inrange values (PowerPC), similarly combining to identity shuffle masks could cause too much UNDEF information to disappear for later combines.

llvm-svn: 325354
2018-02-16 16:22:14 +00:00
Simon Pilgrim 0ffde50f9c [SelectionDAG] Add initial SimplifyDemandedVectorElts support for simplifying VSELECT operands
This just adds a basic pass through - we can add constant selection mask handling in a future patch to fully match InstCombine.

llvm-svn: 325338
2018-02-16 12:21:08 +00:00
Mikhail Maltsev 0a7e107e77 [LegalizeDAG] Fix legalization of SETCC
Summary:
Currently when expanding a SETCC node into a SELECT_CC, LLVM uses
an incorrect type for determining BooleanContent of the result. This
patch fixes the issue.

Fixes PR36079.

Reviewers: rogfer01, javed.absar, efriedma

Reviewed By: efriedma

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43282

llvm-svn: 325325
2018-02-16 09:35:16 +00:00
Craig Topper dac3c1f5c8 [DAGCombiner] Call ExtendUsesToFormExtLoad in (zext (and (load)))->(and (zextload)) even when the and does not have multiple uses
Same for the sign extend case.

Currently we check for multiple uses on the binop. Then we call ExtendUsesToFormExtLoad to capture SetCCs that use the load. So we only end up finding any setccs when the and has additional uses and the load is used by a setcc. I don't think the and having multiple uses is relevant here. I think we should only be checking for the load having multiple uses.

This changes an NVPTX test because we now find that the load has a second use by a truncate, but ExtendUsesToFormExtLoad only looks at setccs it can extend. All other operations just check isTruncateFree. Maybe we should allow widening of an existing truncate even if its not free?

Differential Revision: https://reviews.llvm.org/D43063

llvm-svn: 325289
2018-02-15 20:20:32 +00:00
Simon Pilgrim 1eb5c455c9 [SelectionDAG] Pull out repeated Op.getOpcode(). NFCI.
llvm-svn: 325253
2018-02-15 15:31:00 +00:00
Simon Pilgrim 80663ee986 [SelectionDAG] Add initial implementation of TargetLowering::SimplifyDemandedVectorElts
This is mainly a move of simplifyShuffleOperands from DAGCombiner::visitVECTOR_SHUFFLE to create a more general purpose TargetLowering::SimplifyDemandedVectorElts implementation.

Further features can be moved/added in future patches.

Differential Revision: https://reviews.llvm.org/D42896

llvm-svn: 325232
2018-02-15 12:14:15 +00:00
Alexander Ivchenko 7e5d525bd5 [SelectionDAG][X86] Fix incorrect offset generated for VMASKMOV
When creating high MachineMemOperand for MSTORE/MLOAD we supply
it with the original PointerInfo, while the pointer itself had been incremented.
The patch adds the proper offset to the PointerInfo.

llvm-svn: 325135
2018-02-14 15:55:24 +00:00
Elena Demikhovsky 945b7e5aa6 Adding a width of the GEP index to the Data Layout.
Making a width of GEP Index, which is used for address calculation, to be one of the pointer properties in the Data Layout.
p[address space]:size:memory_size:alignment:pref_alignment:index_size_in_bits.
The index size parameter is optional, if not specified, it is equal to the pointer size.

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

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

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

llvm-svn: 325102
2018-02-14 06:58:08 +00:00
Craig Topper 5ecea9fff5 [SelectionDAG] Remove duplicate code from TargetLowering::SimplifySetCC.
This exact code already exists a little further up.

llvm-svn: 325101
2018-02-14 06:51:57 +00:00
Craig Topper f73ff612ca [DAGCombiner] Add one use check to fold (not (and x, y)) -> (or (not x), (not y))
Summary:
If the and has an additional use we shouldn't invert it. That creates an additional instruction.

While there add a one use check to the transform above that looked similar.

Reviewers: spatel, RKSimon

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43225

llvm-svn: 325019
2018-02-13 16:25:27 +00:00
Sanjay Patel 907b58530f [DAG] fix type of undef returned by getNode()
The bug has been lying dormant, but apparently was never exposed, until
after rL324941 because we didn't return the correct result 
for shifts with undef operands.

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

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

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

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

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

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

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

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

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

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

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

llvm-svn: 324908
2018-02-12 17:03:11 +00:00
Sanjay Patel eb8c408e50 [TargetLowering] try to create -1 constant operand for math ops via demanded bits
This reverses instcombine's demanded bits' transform which always tries to clear bits in constants.

As noted in PR35792 and shown in the test diffs:
https://bugs.llvm.org/show_bug.cgi?id=35792
...we can do better in codegen by trying to form -1. The x86 sub test shows a missed opportunity. 

I did investigate changing instcombine's behavior, but it would be more work to change 
canonicalization in IR. Clearing bits / shrinking constants can allow killing instructions, 
so we'd have to figure out how to not regress those cases.

Differential Revision: https://reviews.llvm.org/D42986

llvm-svn: 324839
2018-02-11 14:38:23 +00:00
Simon Pilgrim 0be5567a89 [X86][SSE] Enable SMIN/SMAX/UMIN/UMAX custom lowering for all legal types
This allows us to recognise more saturation patterns and also simplify some MINMAX codegen that was failing to combine CMPGE comparisons to a legal CMPGT.

Differential Revision: https://reviews.llvm.org/D43014

llvm-svn: 324837
2018-02-11 10:52:37 +00:00
Craig Topper 36f913ee80 [SelectionDAG] Remove TargetLowering::getConstTrueVal. Use SelectionDAG::getBoolConstant in the one place it was used.
SelectionDAG::getBoolConstant was recently introduced. At the time I didn't know getConstTrueVal existed, but I think getBoolConstant is better as it will use the source VT to make sure it can properly detect floating point if it is configured differently.

llvm-svn: 324832
2018-02-11 04:58:58 +00:00
Nirav Dave c8c9d4fe35 [DAG] Make early exit hasPredecessorHelper return true. NFCI.
All uses conservatively assume in early exit case that it will be a
predecessor. Changing default removes checking code in all uses.

llvm-svn: 324797
2018-02-10 02:41:22 +00:00
Stefan Maksimovic dc66ae78c6 [SelectionDAG] Provide adequate register class for RegisterSDNode
When adding operands to machine instructions in case of
RegisterSDNodes, generate a COPY node in case the register class
does not match the one in the instruction definition.

Differental Revision: https://reviews.llvm.org/D35561

llvm-svn: 324733
2018-02-09 13:55:25 +00:00
Vedant Kumar 7fd9a58d8c Revert "WIP: [DAGCombiner] Assert that debug info is preserved"
This reverts commit r324648. It was committed accidentally.

llvm-svn: 324650
2018-02-08 20:27:35 +00:00
Vedant Kumar 28323ff5a3 WIP: [DAGCombiner] Assert that debug info is preserved
llvm-svn: 324648
2018-02-08 20:27:09 +00:00
Craig Topper 9b611e436f [SelectionDAG] Add a helper function for creating a boolean constant based on the target's boolean content
Many in SimplifySetCC and FoldSetCC try to create true or false constants. Some of them query getBooleanContents to figure out whether to use all ones or just 1 for true. But many places do not check and just use 1 without ensuring the VT has an i1 scalar type. Note sure if those places only trigger before type legalization so they only see an i1
type?

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

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

llvm-svn: 324634
2018-02-08 18:55:14 +00:00
Craig Topper c19aed963e [DAGCombiner] Fix a couple mistakes from r324311 by really passing the original load to ExtendSetCCUses.
We're passing the binary op that uses the load instead of the load.

Noticed by inspection. Not sure how to test this because this just prevents the introduction of an extend that will later be truncated and will probably be combined out.

llvm-svn: 324568
2018-02-08 06:27:18 +00:00
Craig Topper 9b9d527427 [DAGCombiner] Don't create truncate nodes in (aext (zextload x)) -> (zextload x) and similar folds. NFCI
The truncate is being used to replace other users of of the load, but we checked that the load only has one use so there are no other uses to replace.

llvm-svn: 324567
2018-02-08 06:04:18 +00:00
Craig Topper cbfe41ac2f [DAGCombiner] Avoid creating truncate nodes in (zext (and (load)))->(and (zextload)) fold until we know for sure we're going to need it. NFCI
The truncate is only needed if the load has additional users. It used to get passed to extendSetCCUses so was created early, but that's no longer the case.

llvm-svn: 324562
2018-02-08 04:38:04 +00:00
Craig Topper bf4ed42606 [DAGCombiner] Rename variable to be slightly better. NFC
We were calling a load LN0 but it came from N0.getOperand(0) so its really more like LN00 if we follow the name used in other places.

llvm-svn: 324561
2018-02-08 04:38:02 +00:00
Nirav Dave efed656873 [SelectionDAG] More Aggressibly prune nodes in AddChains. NFCI.
Travel all chains paths to first non-tokenfactor node can be
exponential work. Add simple redundency check to avoid this.
Fixes PR36264.

llvm-svn: 324491
2018-02-07 17:12:34 +00:00
Eugene Leviant 25347ea895 [LegalizeDAG] Truncate condition operand of ISD::SELECT
Differential revision: https://reviews.llvm.org/D42737

llvm-svn: 324447
2018-02-07 05:38:29 +00:00
Craig Topper 58ecffd857 [DAGCombiner][AMDGPU][X86] Turn cttz/ctlz into cttz_zero_undef/ctlz_zero_undef if we can prove the input is never zero
X86 currently has a late DAG combine after cttz/ctlz are turned into BSR+BSF+CMOV to detect this and remove the CMOV. But we should be able to do this much earlier and avoid creating the cmov all together.

For the changed AMDGPU test case it appears that previously the i8 cttz was type legalized to i16 which introduced an OR with 256 in order to limit the result to 8 on the widened type. At this point the result is known to never be zero, but nothing checked that. Then operation legalization is told to promote all i16 cttz to i32. This introduces an extend and a truncate and another OR with 65536 to limit the result to 16. With the DAG combiner change we are able to prevent the creation of the second OR since the opcode will have been changed to cttz_zero_undef after the first OR. I the lack of the OR caused the instruction to change to v_ffbl_b32_sdwa

Differential Revision: https://reviews.llvm.org/D42985

llvm-svn: 324427
2018-02-06 23:54:37 +00:00
Andrew Kaylor c41499865b Add SelectionDAGDumper support for strict FP nodes
Patch by Kevin P. Neal

llvm-svn: 324416
2018-02-06 22:28:15 +00:00
Sanjay Patel 87ce2fd82d [TargetLowering] use local variable to reduce duplication; NFCI
llvm-svn: 324401
2018-02-06 21:09:42 +00:00
Sanjay Patel e96a9014ab [TargetLowering] use local variables to reduce duplication; NFCI
llvm-svn: 324397
2018-02-06 20:49:28 +00:00
Nirav Dave 27721e8617 [DAG, X86] Improve Dependency analysis when doing multi-node
Instruction Selection

Cleanup cycle/validity checks in ISel (IsLegalToFold,
HandleMergeInputChains) and X86 (isFusableLoadOpStore). Now do a full
search for cycles / dependencies pruning the search when topological
property of NodeId allows.

As part of this propogate the NodeId-based cutoffs to narrow
hasPreprocessorHelper searches.

Reviewers: craig.topper, bogner

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D41293

llvm-svn: 324359
2018-02-06 16:14:29 +00:00
Craig Topper ee1f34eb9a [DAGCombiner] Pass the original load to ExtendSetCCUses not the turncate.
Summary:
This method is trying to use the truncate node to find which SETCC operand should be replaced directly with the extended load.

This used to work correctly because all uses of the original load were replaced by the truncate before this function was called. So this was used to effectively bypass the truncate and find the load under it.

All but one of the callers now call this before the truncate has replaced the laod so the setcc doesn't yet use the truncate. To account for this we should pass the original load instead.

I changed the order of that one caller to make this work there too.

I don't have a test case because this is probably hidden by later DAG combines causing the extend and truncate to cancel out. I assume this way is a little more efficient and matches what was originally intended.

Reviewers: RKSimon, spatel, niravd

Reviewed By: niravd

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42878

llvm-svn: 324311
2018-02-06 03:23:27 +00:00
Krzysztof Parzyszek fee3f419ae [SDAG] Legalize all CondCodes by inverting them and/or swapping operands
Differential Revision: https://reviews.llvm.org/D42788

llvm-svn: 324274
2018-02-05 21:27:16 +00:00
Craig Topper fc5bd023dd [DAGCombiner] When folding fold (sext/zext (and/or/xor (sextload/zextload x), cst)) -> (and/or/xor (sextload/zextload x), (sext/zext cst)) make sure we check the legality of the full extended load.
Summary:
If the load is already an extended load we should be using the memory VT for the legality check, not just the VT of the current extension.

I don't have a test case, just noticed it while investigating some load extension improvements.

Reviewers: RKSimon, spatel, niravd

Reviewed By: niravd

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42783

llvm-svn: 324181
2018-02-03 23:00:31 +00:00
Simon Pilgrim 4df6499f10 [SelectionDAG] Don't use simple VT in generic shuffle code
Better to assume that any value type may be commuted, not just MVTs.

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

llvm-svn: 324179
2018-02-03 21:34:42 +00:00
Jonas Paulsson 422dfbf7cc [SelectionDAG] Consider endianness in scalarizeVectorStore().
When handling vectors with non byte-sized elements, reverse the order of the
elements in the built integer if the target is Big-Endian.

SystemZ tests updated.

Review: Eli Friedman, Ulrich Weigand.
https://reviews.llvm.org/D42786

llvm-svn: 324063
2018-02-02 08:48:02 +00:00
Jonas Paulsson ad089fe46e [SelectionDAG] Add an assert in getNode() for EXTRACT_VECTOR_ELT.
When getNode() is called to create an EXTRACT_VECTOR_ELT, assert that
the result VT is at least as wide as the vector element type.

Review: Eli Friedman
llvm-svn: 324061
2018-02-02 08:21:53 +00:00
Craig Topper a5944aade1 [DAGCombiner] When folding (insert_subvector undef, (bitcast (extract_subvector N1, Idx)), Idx) -> (bitcast N1) make sure that N1 has the same total size as the original output
We were only checking the element count, but not the total width. This could cause illegal bitcasts to be created if for example the output was 512-bits, but N1 is 256 bits, and the extraction size was 128-bits.

Fixes PR36199

Differential Revision: https://reviews.llvm.org/D42809

llvm-svn: 324002
2018-02-01 20:48:50 +00:00
Sanjay Patel 657e5d8d41 [DAGCombiner] filter out denorm inputs when calculating sqrt estimate (PR34994)
As shown in the example in PR34994:
https://bugs.llvm.org/show_bug.cgi?id=34994
...we can return a very wrong answer (inf instead of 0.0) for square root when 
using a reciprocal square root estimate instruction.

Here, I've conditionalized the filtering out of denorms based on the function 
having "denormal-fp-math"="ieee" in its attributes. The other options for this 
attribute are 'preserve-sign' and 'positive-zero'.

So we don't generate this extra code by default with just '-ffast-math' (because 
then there's no denormal attribute string at all), but it works if you specify 
'-ffast-math -fdenormal-fp-math=ieee' from clang. 

As noted in the review, there may be other problems in clang that affect the 
results depending on platform (Linux x86 at least), but this should allow 
creating the desired codegen.

Differential Revision: https://reviews.llvm.org/D42323

llvm-svn: 323981
2018-02-01 16:57:18 +00:00
Nirav Dave 18f7f60e17 [SelectionDAG] Fix UpdateChains handling of TokenFactors
Summary:
In Instruction Selection UpdateChains replaces all matched Nodes'
chain references including interior token factors and deletes them.
This may allow nodes which depend on these interior nodes but are not
part of the set of matched nodes to be left with a dangling dependence.
Avoid this by doing the replacement for matched non-TokenFactor nodes.

Fixes PR36164.

Reviewers: jonpa, RKSimon, bogner

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D42754

llvm-svn: 323977
2018-02-01 16:11:59 +00:00
Dean Michael Berris cdca0730be [XRay][compiler-rt+llvm] Update XRay register stashing semantics
Summary:
This change expands the amount of registers stashed by the entry and
`__xray_CustomEvent` trampolines.

We've found that since the `__xray_CustomEvent` trampoline calls can show up in
situations where the scratch registers are being used, and since we don't
typically want to affect the code-gen around the disabled
`__xray_customevent(...)` intrinsic calls, that we need to save and restore the
state of even the scratch registers in the handling of these custom events.

Reviewers: pcc, pelikan, dblaikie, eizan, kpw, echristo, chandlerc

Reviewed By: echristo

Subscribers: chandlerc, echristo, hiraditya, davide, dblaikie, llvm-commits

Differential Revision: https://reviews.llvm.org/D40894

llvm-svn: 323940
2018-02-01 02:21:54 +00:00
Matt Arsenault df0f25070c DAG: Fix not truncating when promoting bswap/bitreverse
These need to convert back to the original type, like any
other promotion.

llvm-svn: 323932
2018-01-31 23:54:16 +00:00
Nirav Dave c3a1e16db1 [DAG] Prevent NodeId pruning of TokenFactors in Instruction Selection.
Summary:
Instruction Selection preserves relative orders of all nodes save
TokenFactors which we treat specially. As a result Node Ids for
TokenFactors may violate the topological ordering and should not be
considered as valid pruning candidates in predecessor search.

Fixes PR35316.

Reviewers: RKSimon, hfinkel

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D42701

llvm-svn: 323880
2018-01-31 15:23:17 +00:00
Roger Ferrer Ibanez aea4208720 [ARM] Allow the scheduler to clone a node with glue to avoid a copy CPSR ↔ GPR.
In Thumb 1, with the new ADDCARRY / SUBCARRY the scheduler may need to do
copies CPSR ↔ GPR but not all Thumb1 targets implement them.

The schedule can attempt, before attempting a copy, to clone the instructions
but it does not currently do that for nodes with input glue. In this patch we
introduce a target-hook to let the hook decide if a glued machinenode is still
eligible for copying. In this case these are ARM::tADCS and ARM::tSBCS .

As a follow-up of this change we should actually implement the copies for the
Thumb1 targets that do implement them and restrict the hook to the targets that
can't really do such copy as these clones are not ideal.

This change fixes PR35836.

Differential Revision: https://reviews.llvm.org/D42051

llvm-svn: 323857
2018-01-31 09:23:43 +00:00
Simon Dardis daaeaba665 [mips] Fix incorrect sign extension for fpowi libcall
PR36061 showed that during the expansion of ISD::FPOWI, that there
was an incorrect zero extension of the integer argument which for
MIPS64 would then give incorrect results. Address this with the
existing mechanism for correcting sign extensions.

This resolves PR36061.

Thanks to James Cowgill for reporting the issue!

Reviewers: atanasyan, hfinkel

Differential Revision: https://reviews.llvm.org/D42537

llvm-svn: 323781
2018-01-30 16:24:10 +00:00
Dan Gohman 832092ca12 [SelectionDAG]: Ignore "returned" in the presence of an implicit sret.
When a function return value can't be directly lowered, such as
returning an i128 on WebAssembly, as indicated by the CanLowerReturn
target hook, SelectionDAGBuilder can translate it to return the
value through a hidden sret-like argument.

If such a function has an argument with the "returned" attribute,
the attribute can't be automatically lowered, because the function
no longer has a normal return value. For now, just discard the
"returned" attribute.

This fixes PR36128.

llvm-svn: 323715
2018-01-30 00:14:40 +00:00
Craig Topper 62b62356fa [X86] Make foldLogicOfSetCCs work better for vectors pre legal types/operations
Summary:
There's a check in the code to only check getSetCCResultType after LegalOperations or if the type is MVT::i1. But the i1 check is only allowing scalar types through. I think it should check that the scalar type is MVT::i1 so that it will work for vectors.

The changed test already does this combine with AVX512VL where getSetCCResultType returns vXi1. But with avx512f and no VLX getSetCCResultType returns a type matching the width of the input type.

Reviewers: spatel, RKSimon

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42619

llvm-svn: 323631
2018-01-29 07:52:55 +00:00
Hiroshi Inoue c8e9245816 [NFC] fix trivial typos in comments and documents
"to to" -> "to"

llvm-svn: 323628
2018-01-29 05:17:03 +00:00
Craig Topper 2c570eaa00 [TargetLowering] Teach TargetLowering::SimplifySetCC to simplify setcc of vXi1 vectors into logic ops.
This transform was already being done for setcc of scalar i1. This extends it to vectors.

llvm-svn: 323585
2018-01-27 09:10:58 +00:00
Craig Topper c80f0ced84 [SelectionDAG] Make DAGTypeLegalizer::PromoteSetCCOperands handle SETEQ/SETNE correctly for vector types.
The code was using getValueSizeInBits and combining with the result of a call to DAG.ComputeNumSignBits. But for vector types getValueSizeInBits returns the width of the full vector while ComputeNumSignBits is going to give a number no larger than the width of a single element. So we should be using getScalarValueSizeInBits to get the element width.

llvm-svn: 323583
2018-01-27 08:41:03 +00:00
Craig Topper 8f324bb1a4 [SelectionDAGISel] Add a debug print before call to Select. Adjust where blank lines are printed during isel process to make things more sensibly grouped.
Previously some targets printed their own message at the start of Select to indicate what they were selecting. For the targets that didn't, it means there was no print of the root node before any custom handling in the target executed. So if the target did something custom and never called SelectNodeCommon, no print would be made. For the targets that did print a message in Select, if they didn't custom handle a node SelectNodeCommon would reprint the root node before walking the isel table.

It seems better to just print the message before the call to Select so all targets behave the same. And then remove the root node printing from SelectNodeCommon and just leave a message that says we're starting the table search.

There were also some oddities in blank line behavior. Usually due to a \n after a call to SelectionDAGNode::dump which already inserted a new line.

llvm-svn: 323551
2018-01-26 19:34:20 +00:00
Nirav Dave 9896238dc9 [DAG] Teach findBaseOffset to interpret indexes of indexed memory operations
Indexed outputs are addition / subtractions and can be interpreted as such.

llvm-svn: 323539
2018-01-26 16:51:27 +00:00
Simon Pilgrim f531cf8964 [DAGCombine] reduceBuildVecToShuffle - ensure EXTRACT_VECTOR_ELT index is in range
From OSS Fuzz Test Case #5688

llvm-svn: 323535
2018-01-26 15:50:20 +00:00
Hiroshi Inoue 0909ca132f [NFC] fix trivial typos in comments and documents
"in in" -> "in", "on on" -> "on" etc.

llvm-svn: 323508
2018-01-26 08:15:29 +00:00
Craig Topper b5c45e0509 [SelectionDAG] Replace a std::vector<SDValue> with a SmallVector.
It likely the number of elements in the type we're legalizing here is reasonably small.

llvm-svn: 323505
2018-01-26 07:15:22 +00:00
Amara Emerson f386e2b081 [GlobalISel] Don't fall back to FastISel.
Apparently checking the pass structure isn't enough to ensure that we don't fall
back to FastISel, as it's set up as part of the SelectionDAGISel.

llvm-svn: 323369
2018-01-24 19:59:29 +00:00
Sven van Haastregt e8404780c3 [DAGCombiner] Bail out if vector size is not a multiple
For the included test case, the DAG transformation
  concat_vectors(scalar, undef) -> scalar_to_vector(sclr)
would attempt to create a v2i32 vector for a v9i8
concat_vector.  Bail out to avoid creating a bitcast with
mismatching sizes later on.

Differential Revision: https://reviews.llvm.org/D42379

llvm-svn: 323312
2018-01-24 09:53:47 +00:00
Jonas Paulsson 7ad28863fb [SelectionDAG] Fix codegen of vector stores with non byte-sized elements.
This was completely broken, but hopefully fixed by this patch.

In cases where it is needed, a vector with non byte-sized elements is stored
by extracting, zero-extending, shift:ing and or:ing the elements into an
integer of the same width as the vector, which is then stored.

Review: Eli Friedman, Ulrich Weigand
https://reviews.llvm.org/D42100#inline-369520
https://bugs.llvm.org/show_bug.cgi?id=35520

llvm-svn: 323042
2018-01-20 16:05:10 +00:00
Ulrich Weigand 5605be9e50 [SelectionDAG] Teach computeKnownBits about ATOMIC_CMP_SWAP_WITH_SUCCESS boolean return value
The second return value of ATOMIC_CMP_SWAP_WITH_SUCCESS is known to be a
boolean, and should therefore be treated by computeKnownBits just like
the second return values of SMULO / UMULO.

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

llvm-svn: 322985
2018-01-19 20:47:14 +00:00
Daniel Neilson 1e68724d24 Remove alignment argument from memcpy/memmove/memset in favour of alignment attributes (Step 1)
Summary:
 This is a resurrection of work first proposed and discussed in Aug 2015:
   http://lists.llvm.org/pipermail/llvm-dev/2015-August/089384.html
and initially landed (but then backed out) in Nov 2015:
   http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html

 The @llvm.memcpy/memmove/memset intrinsics currently have an explicit argument
which is required to be a constant integer. It represents the alignment of the
dest (and source), and so must be the minimum of the actual alignment of the
two.

 This change is the first in a series that allows source and dest to each
have their own alignments by using the alignment attribute on their arguments.

 In this change we:
1) Remove the alignment argument.
2) Add alignment attributes to the source & dest arguments. We, temporarily,
   require that the alignments for source & dest be equal.

 For example, code which used to read:
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 100, i32 4, i1 false)
will now read
  call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 4 %dest, i8* align 4 %src, i32 100, i1 false)

 Downstream users may have to update their lit tests that check for
@llvm.memcpy/memmove/memset call/declaration patterns. The following extended sed script
may help with updating the majority of your tests, but it does not catch all possible
patterns so some manual checking and updating will be required.

s~declare void @llvm\.mem(set|cpy|move)\.p([^(]*)\((.*), i32, i1\)~declare void @llvm.mem\1.p\2(\3, i1)~g
s~call void @llvm\.memset\.p([^(]*)i8\(i8([^*]*)\* (.*), i8 (.*), i8 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i8(i8\2* \3, i8 \4, i8 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i16\(i8([^*]*)\* (.*), i8 (.*), i16 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i16(i8\2* \3, i8 \4, i16 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i32\(i8([^*]*)\* (.*), i8 (.*), i32 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i32(i8\2* \3, i8 \4, i32 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i64\(i8([^*]*)\* (.*), i8 (.*), i64 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i64(i8\2* \3, i8 \4, i64 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i128\(i8([^*]*)\* (.*), i8 (.*), i128 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.memset.p\1i128(i8\2* \3, i8 \4, i128 \5, i1 \6)~g
s~call void @llvm\.memset\.p([^(]*)i8\(i8([^*]*)\* (.*), i8 (.*), i8 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i8(i8\2* align \6 \3, i8 \4, i8 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i16\(i8([^*]*)\* (.*), i8 (.*), i16 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i16(i8\2* align \6 \3, i8 \4, i16 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i32\(i8([^*]*)\* (.*), i8 (.*), i32 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i32(i8\2* align \6 \3, i8 \4, i32 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i64\(i8([^*]*)\* (.*), i8 (.*), i64 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i64(i8\2* align \6 \3, i8 \4, i64 \5, i1 \7)~g
s~call void @llvm\.memset\.p([^(]*)i128\(i8([^*]*)\* (.*), i8 (.*), i128 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.memset.p\1i128(i8\2* align \6 \3, i8 \4, i128 \5, i1 \7)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i8\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i8 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i8(i8\3* \4, i8\5* \6, i8 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i16\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i16 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i16(i8\3* \4, i8\5* \6, i16 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i32\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i32 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i32(i8\3* \4, i8\5* \6, i32 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i64\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i64 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i64(i8\3* \4, i8\5* \6, i64 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i128\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i128 (.*), i32 [01], i1 ([^)]*)\)~call void @llvm.mem\1.p\2i128(i8\3* \4, i8\5* \6, i128 \7, i1 \8)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i8\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i8 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i8(i8\3* align \8 \4, i8\5* align \8 \6, i8 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i16\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i16 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i16(i8\3* align \8 \4, i8\5* align \8 \6, i16 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i32\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i32 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i32(i8\3* align \8 \4, i8\5* align \8 \6, i32 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i64\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i64 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i64(i8\3* align \8 \4, i8\5* align \8 \6, i64 \7, i1 \9)~g
s~call void @llvm\.mem(cpy|move)\.p([^(]*)i128\(i8([^*]*)\* (.*), i8([^*]*)\* (.*), i128 (.*), i32 ([0-9]*), i1 ([^)]*)\)~call void @llvm.mem\1.p\2i128(i8\3* align \8 \4, i8\5* align \8 \6, i128 \7, i1 \9)~g

 The remaining changes in the series will:
Step 2) Expand the IRBuilder API to allow creation of memcpy/memmove with differing
   source and dest alignments.
Step 3) Update Clang to use the new IRBuilder API.
Step 4) Update Polly to use the new IRBuilder API.
Step 5) Update LLVM passes that create memcpy/memmove calls to use the new IRBuilder API,
        and those that use use MemIntrinsicInst::[get|set]Alignment() to use
        getDestAlignment() and getSourceAlignment() instead.
Step 6) Remove the single-alignment IRBuilder API for memcpy/memmove, and the
        MemIntrinsicInst::[get|set]Alignment() methods.

Reviewers: pete, hfinkel, lhames, reames, bollu

Reviewed By: reames

Subscribers: niosHD, reames, jholewinski, qcolombet, jfb, sanjoy, arsenm, dschuff, dylanmckay, mehdi_amini, sdardis, nemanjai, david2050, nhaehnle, javed.absar, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, llvm-commits

Differential Revision: https://reviews.llvm.org/D41675

llvm-svn: 322965
2018-01-19 17:13:12 +00:00
Sanjay Patel 0e690b05d1 [TargetLowering] add punctuation for readability; NFC
llvm-svn: 322855
2018-01-18 15:25:32 +00:00
Sam Parker 1f8c035d6b [SelectionDAG] Convert assert to condtion
Follow-up to r322120 which can cause assertions for AArch64 because
v1f64 and v1i64 are legal types.

Differential Revision: https://reviews.llvm.org/D42097

llvm-svn: 322823
2018-01-18 09:22:24 +00:00
Craig Topper 7f0d85ec1e [DAGCombiner] Add a DAG combine to turn a splat build_vector where the splat elemnt is a bitcast from a vector type into a concat_vector
For example, a build_vector of i64 bitcasted from v2i32 can be turned into a concat_vectors of the v2i32 vectors with a bitcast to a vXi64 type

Differential Revision: https://reviews.llvm.org/D42090

llvm-svn: 322811
2018-01-18 04:17:06 +00:00
Eli Friedman c60a23a6af [LegalizeDAG] Fix ATOMIC_CMP_SWAP_WITH_SUCCESS legalization.
The code wasn't zero-extending correctly, so the comparison could
spuriously fail.

Adds some AArch64 tests to cover this case.

Inspired by D41791.

Differential Revision: https://reviews.llvm.org/D41798

llvm-svn: 322767
2018-01-17 22:04:36 +00:00
Benjamin Kramer 736a343e97 Revert "[DAG] Elide overlapping stores"
This reverts commit r322085. Internal PPC testing is still showing the
same symptoms as when this patch landed the last time.

llvm-svn: 322474
2018-01-15 10:57:24 +00:00
Daniel Neilson 2409d24201 [NFC] Change MemIntrinsicInst::setAlignment() to take an unsigned instead of a Constant
Summary:
 In preparation for https://reviews.llvm.org/D41675 this NFC changes this
prototype of MemIntrinsicInst::setAlignment() to accept an unsigned instead
of a Constant.

llvm-svn: 322403
2018-01-12 21:33:37 +00:00
Adrian Prantl 29102b3002 dag-combine: Transfer debug information when folding (zext (truncate x))
-> (zext (truncate x))

This patch adds debug info support to the dagcombine rule (zext
(truncate x)) -> (zext (truncate x)).

Differential Revision: https://reviews.llvm.org/D41924

llvm-svn: 322304
2018-01-11 18:35:12 +00:00
Zvi Rackover 999e6c2967 DAGCombine: Let truncates negate extension through extract-subvector
Summary:
Fold cases such as:
(v8i8 truncate (v8i32 extract_subvector (v16i32 sext (v16i8 V), Idx)))
->
(v8i8 extract_subvector (v16i8 V), Idx)

This can be generalized to cases where the truncate and extend do not
fully cancel each other out, but it may require querying the target
about profitability.

Reviewers: RKSimon, craig.topper, spatel, efriedma

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41927

llvm-svn: 322300
2018-01-11 18:02:33 +00:00
Jonas Paulsson 9b395a12ed [VectorLegalizer] Remove broken code in ExpandStore.
The code that is supposed to "Round odd types to the next pow of two" seems
broken and as well completely unused (untested). It also seems that
ExpandStore really shouldn't ever change the memory VT, which this in fact
does.

As a first step in fixing the broken handling of vector stores (of irregular
types, e.g. an i1 vector), this code is removed. For discussion, see
https://bugs.llvm.org/show_bug.cgi?id=35520.

Review: Eli Friedman
llvm-svn: 322275
2018-01-11 13:03:21 +00:00
Craig Topper af4eb17223 [SelectionDAG][X86] Explicitly store the scale in the gather/scatter ISD nodes
Currently we infer the scale at isel time by analyzing whether the base is a constant 0 or not. If it is we assume scale is 1, else we take it from the element size of the pass thru or stored value. This seems a little weird and I think it makes more sense to make it explicit in the DAG rather than doing tricky things in the backend.

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

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

llvm-svn: 322210
2018-01-10 19:16:05 +00:00
Jonas Paulsson 9222b91e24 [SelectionDAGBuilder] Chain prefetches less aggressively.
Prefetches used to always be chained between any previous and following
memory accesses. The problem with this was that later optimizations, such as
folding of a load into the user instruction, got disrupted.

This patch relaxes the chaining of prefetches in order to remedy this.

Reveiw: Hal Finkel
https://reviews.llvm.org/D38886

llvm-svn: 322163
2018-01-10 09:33:00 +00:00
Tim Renouf d68fa1be57 [SelectionDAG] Fixed f16-from-vector promotion problem
Summary:
In the case of an fp_extend of v1f16 to v1f32 where the v1f16 is the
result of a bitcast from i16, avoid creating an illegal fp16_to_fp where
the input is not a vector and the result is a v1f32.

V2: The fix is now to avoid vector scalarization creating a v1->scalar
bitcast.

Reviewers: srhines, t.p.northover

Subscribers: nhaehnle, llvm-commits, dstuttard, t-tye, yaxunl, wdng, kzhuravl, arsenm

Differential Revision: https://reviews.llvm.org/D41126

llvm-svn: 322120
2018-01-09 21:36:25 +00:00
Sanjay Patel 37e28e40cb [SelectionDAG] lower math intrinsics to finite version of libcalls when possible (PR35672)
Ingredients in this patch:
1. Add HANDLE_LIBCALL defs for finite mathlib functions that correspond to LLVM intrinsics.
2. Plumbing to send TargetLibraryInfo down to SelectionDAGLegalize.
3. Relaxed math and library checking in SelectionDAGLegalize::ConvertNodeToLibcall() to choose finite libcalls.

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

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

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

llvm-svn: 322087
2018-01-09 15:41:00 +00:00
Nirav Dave 30304a3bd7 [DAG] Elide overlapping stores
Relanding after fixing handling of pre-indexed memory operations in
BaseIndexOffset analysis (r322003).

Extend overlapping store elision to handle overwrites of stores by
larger stores.

Reviewers: craig.topper, rnk, t.p.northover

Subscribers: javed.absar, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D40969

llvm-svn: 322085
2018-01-09 15:23:12 +00:00
Nirav Dave 6e2d03d410 [DAG] Teach BaseIndexOffset to correctly handle with indexed operations
BaseIndexOffset address analysis incorrectly ignores offsets folded
into indexed memory operations causing potential errors in alias
analysis of pre-indexed operations.

Reviewers: efriedma, RKSimon, hfinkel, jyknight

Subscribers: hiraditya, javed.absar, llvm-commits

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

llvm-svn: 322003
2018-01-08 16:21:35 +00:00
Sam Parker 3800f0f11d [DAGCombine] Fix for PR35761
I had falsely assumed that constant operands would be operand(1) of
the bin ops that may need their constant operand to be masked.

Bugzilla: https://bugs.llvm.org/show_bug.cgi?id=35761

Differential Revision: https://reviews.llvm.org/D41667

llvm-svn: 321991
2018-01-08 13:21:24 +00:00
Simon Pilgrim 998180dad3 [DAG] Fix for Bug PR34620 - Allow SimplifyDemandedBits to look through bitcasts
Allow SimplifyDemandedBits to use TargetLoweringOpt::computeKnownBits to look through bitcasts. This can help simplifying in some cases where bitcasts of constants generated during or after legalization can't be folded away, and thus didn't get picked up by SimplifyDemandedBits. This fixes PR34620, where a redundant pand created during legalization from lowering and lshr <16xi8> wasn't being simplified due to the presence of a bitcasted build_vector as an operand.

Committed on the behalf of @sameconrad (Sam Conrad)

Differential Revision: https://reviews.llvm.org/D41643

llvm-svn: 321969
2018-01-07 19:09:40 +00:00
Craig Topper d58c165545 [X86] Make v2i1 and v4i1 legal types without VLX
Summary:
There are few oddities that occur due to v1i1, v8i1, v16i1 being legal without v2i1 and v4i1 being legal when we don't have VLX. Particularly during legalization of v2i32/v4i32/v2i64/v4i64 masked gather/scatter/load/store. We end up promoting the mask argument to these during type legalization and then have to widen the promoted type to v8iX/v16iX and truncate it to get the element size back down to v8i1/v16i1 to use a 512-bit operation. Since need to fill the upper bits of the mask we have to fill with 0s at the promoted type.

It would be better if we could just have the v2i1/v4i1 types as legal so they don't undergo any promotion. Then we can just widen with 0s directly in a k register. There are no real v4i1/v2i1 instructions anyway. Everything is done on a larger register anyway.

This also fixes an issue that we couldn't implement a masked vextractf32x4 from zmm to xmm properly.

We now have to support widening more compares to 512-bit to get a mask result out so new tablegen patterns got added.

I had to hack the legalizer for widening the operand of a setcc a bit so it didn't try create a setcc returning v4i32, extract from it, then try to promote it using a sign extend to v2i1. Now we create the setcc with v4i1 if the original setcc's result type is v2i1. Then extract that and don't sign extend it at all.

There's definitely room for improvement with some follow up patches.

Reviewers: RKSimon, zvi, guyblank

Reviewed By: RKSimon

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D41560

llvm-svn: 321967
2018-01-07 18:20:37 +00:00
Craig Topper d461aefe5f [PowerPC] Add an ISD::TRUNCATE to the legalization for ppc_is_decremented_ctr_nonzero
Summary:
I believe legalization is really expecting that ReplaceNodeResults will return something with the same type as the thing that's being legalized. Ultimately, it uses the output to replace the uses in the DAG so the type should match to make that work.

There are two relevant cases here. When crbits are enabled, then i1 is a legal type and getSetCCResultType should return i1. In this case, the truncate will be between i1 and i1 and should be removed (SelectionDAG::getNode does this). Otherwise, getSetCCResultType will be i32 and the legalizer will promote the truncate to be i32 -> i32 which will be similarly removed.

With this fixed we can remove some code from PromoteIntRes_SETCC that seemed to only exist to deal with the intrinsic being replaced with a larger type without changing the other operand. With the truncate being used for connectivity this doesn't happen anymore.

Reviewers: hfinkel

Reviewed By: hfinkel

Subscribers: nemanjai, llvm-commits, kbarton

Differential Revision: https://reviews.llvm.org/D41654

llvm-svn: 321959
2018-01-07 07:51:36 +00:00
Sam Parker 1ad085b808 [DAGCombine] Fix for PR37563
While searching for loads to be narrowed, equal sized loads were not
added to the list, resulting in anyext loads not being converted to
zext loads.

https://bugs.llvm.org/show_bug.cgi?id=35763

Differential Revision: https://reviews.llvm.org/D41628

llvm-svn: 321862
2018-01-05 08:47:23 +00:00
Amara Emerson 8a100dd2a6 [DAGCombine] Ensure SDNode use iterator is incremented properly.
Fixes an ASAN bug found by oss-fuzz.

llvm-svn: 321813
2018-01-04 18:38:45 +00:00
Simon Pilgrim ec0a2fb703 [DAGCombine] Handle out of range EXTRACT_VECTOR_ELT indices
Handle this in DAGCombiner::visitEXTRACT_VECTOR_ELT the same as we already do in SelectionDAG::getNode and use APInt instead of getZExtValue.

This should also fix oss-fuzz #4910

llvm-svn: 321767
2018-01-03 22:42:33 +00:00
Daniel Jasper cc4903e2ba Revert r321089: "[DAG] Elide overlapping store" (and subsequent fix in r321204)
Our internal testing has revealed has discovered bugs in PPC builds.
I have forward reproduction instructions to the original author (Nirav).

llvm-svn: 321649
2018-01-02 14:38:52 +00:00
Sam Parker 3570c554b5 [DAGCombine] Fix for PR35765
Remove the acceptance of ANY_EXTEND nodes while trying to move and
nodes back to loads.

Bugzilla: https://bugs.llvm.org/show_bug.cgi?id=35765

Differential Revision: https://reviews.llvm.org/D41625

llvm-svn: 321641
2018-01-02 10:19:01 +00:00
Craig Topper e3b6bd337a [SelectionDAG] Teach WidenVecOp_Convert to widen the operation if a widened result type would still be legal.
llvm-svn: 321638
2018-01-02 07:30:53 +00:00
Craig Topper 3e528c7518 [SelectionDAG] Remove ifs on getTypeAction being TypeWidenVector from some of the WideVecOp handlers.
We should only be in the handler if the tyep action is TypeWidenVector. There's no reason to try to do anything else.

llvm-svn: 321635
2018-01-02 01:55:07 +00:00
Craig Topper a4f9997675 [SelectionDAG][X86][AArch64] Require targets to specify the promotion type when using setOperationAction Promote for INT_TO_FP and FP_TO_INT
Currently the promotion for these ignores the normal getTypeToPromoteTo and instead just tries to double the element width. This is because the default behavior of getTypeToPromote to just adds 1 to the SimpleVT, which has the affect of increasing the element count while keeping the scalar size the same.

If multiple steps are required to get to a legal operation type, int_to_fp will be promoted multiple times. And fp_to_int will keep trying wider types in a loop until it finds one that works.

getTypeToPromoteTo does have the ability to query a promotion map to get the type and not do the increasing behavior. It seems better to just let the target specify the promotion type in the map explicitly instead of letting the legalizer iterate via widening.

FWIW, it's worth I think for any other vector operations that need to be promoted, we have to specify the type explicitly because the default behavior of getTypeToPromote isn't useful for vectors. The other types of promotion already require either the element count is constant or the total vector width is constant, but neither happens by incrementing the SimpleVT enum.

Differential Revision: https://reviews.llvm.org/D40664

llvm-svn: 321629
2018-01-01 19:21:35 +00:00
Benjamin Kramer c7fc81e659 Use phi ranges to simplify code. No functionality change intended.
llvm-svn: 321585
2017-12-30 15:27:33 +00:00