Commit Graph

26866 Commits

Author SHA1 Message Date
Craig Topper ba375263e8 [DAGCombiner][X86] Teach visitCONCAT_VECTORS to combine (concat_vectors (concat_vectors X, Y), undef)) -> (concat_vectors X, Y, undef, undef)
I also had to add a new combine to X86's combineExtractSubvector to prevent a regression.

This helps our vXi1 code see the full concat operation and allow it optimize undef to a zero if there is already a zero in the concat. This helped us use a movzx instead of an AND in some of the tests. In those tests, one concat comes from SelectionDAGBuilder and the second comes from type legalization of v4i1->i4 bitcasts which uses an additional concat. Though these changes weren't my original motivation.

I'm looking at making X86ISelLowering's narrowShuffle emit a concat_vectors instead of an insert_subvector since concat_vectors is more canonical during early DAG combine. This patch helps prevent a regression from my experiments with that.

Differential Revision: https://reviews.llvm.org/D66456

llvm-svn: 369459
2019-08-20 22:12:50 +00:00
Sean Fertile 1e46d4cec5 Adds support for writing the .bss section for XCOFF object files.
Adds Wrapper classes for MCSymbol and MCSection into the XCOFF target
object writer. Also adds a class to represent the top-level sections, which we
materialize in the ObjectWriter.

executePostLayoutBinding will map all csects into the appropriate
container depending on its storage mapping class, and map all symbols
into their containing csect. Once all symbols have been processed we
- Assign addresses and symbol table indices.
- Calaculte section sizes.
- Build the section header table.
- Assign the sections raw-pointer value for non-virtual sections.

Since the .bss section is virtual, writing the header table is enough to
add support. Writing of a sections raw data, or of any relocations is
not included in this patch.

Testing is done by dumping the section header table, but it needs to be
extended to include dumping the symbol table once readobj support for
dumping auxiallary entries lands.

Differential Revision: https://reviews.llvm.org/D65159

llvm-svn: 369454
2019-08-20 22:03:18 +00:00
Aditya Nandakumar 08bd080872 [GlobalISel] Handle multiple registers in dbg.value intrinsic
https://reviews.llvm.org/D66077

The value passed into dbg.value may relate to multiple registers,
each of which need a DBG_VALUE.

This fix calls MIRBuilder.buildDirectDbgValue for each register.

Without this, IR passed in from flang-compiler/flang may fail an
assertion in getOrCreateVReg.

Patch by : peterwaller-arm.

llvm-svn: 369403
2019-08-20 16:28:37 +00:00
Thomas Raoux be699bf389 [CodeGen] Add a pass to do block predication on SSA machine IR.
For targets requiring aggressive scheduling and/or software pipeline we need to
    apply predication before preRA scheduling. This adds a pass re-using the early
    if-cvt infrastructure but generating predicated instructions instead of
    speculatively executing instructions. It allows doing if conversion on blocks
    containing instructions with side-effects. The pass re-use the target hook from
    postRA if-conversion to let the target decide on the heuristic to apply.

    Differential Revision: https://reviews.llvm.org/D66190

llvm-svn: 369395
2019-08-20 15:54:59 +00:00
Karl-Johan Karlsson 40da6be2bd [AsmPrinter] Remove const qualifier from EmitBasicBlockStart.
Overriders may want to modify state in it. AMDGPU wants
to, but has to make its members mutable in order to do so.

Besides, EmitBasicBlockEnd is not const, so why should
Start be?

Patch by Bevin Hansson.

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D66341

llvm-svn: 369325
2019-08-20 05:13:57 +00:00
Vyacheslav Zakharin f7229ac7d8 Fixed placement of llvm.global_dtors on Windows.
Differential revision: https://reviews.llvm.org/D66373

llvm-svn: 369299
2019-08-19 21:07:03 +00:00
Craig Topper 93c2787193 [CGP] Remove ModifiedDT from the makeBitReverse loop
I don't think anything in this loop modifies the control flow and we don't restart any iteration after setting the flag.

This code was added in http://reviews.llvm.org/D16893 but looking at the test case added there the code that caused the dominator tree to change was merging blocks with their predecessor not the bitreverse optimization.

Differential Revision: https://reviews.llvm.org/D66366

llvm-svn: 369283
2019-08-19 18:02:24 +00:00
Roman Lebedev edfaee0811 [TargetLowering] x s% C == 0 fold: vector divisor with INT_MIN handling
Summary:
The general fold is only valid for positive divisors.
Which effectively means, it is invalid for `INT_MIN` divisors,
and we currently bailout if we see them.

But that is too strict, we can just fix-up the results.
For that, let's do a second computation 'in parallel':
```
Name: srem -> and
Pre: isPowerOf2(C)
%o = srem i8 %X, C
%r = icmp eq %o, 0
  =>
%n = and i8 %X, C-1
%r = icmp eq %n, 0
```
https://rise4fun.com/Alive/Sup

And then just blend results: if the divisor was `INT_MIN`,
pick the value we got via bit-test,
else pick the value from general fold.

There's interesting observation - `ISD::ROTR` is set to
`LegalizeAction::Expand` before AVX512, so we should not
treat `INT_MIN` divisor as even; and as it can be seen
while `@test_srem_odd_even_one` improves on all run-lines,
`@test_srem_odd_even_INT_MIN` only improves for AVX512.

Reviewers: RKSimon, craig.topper, spatel

Reviewed By: RKSimon

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66300

llvm-svn: 369268
2019-08-19 15:01:42 +00:00
Jinsong Ji 0776da5236 [PeepholeOptimizer] Don't assume bitcast def always has input
Summary:
If we have a MI marked with bitcast bits, but without input operands,
PeepholeOptimizer might crash with assert.

eg:
If we apply the changes in PPCInstrVSX.td as in this patch:

[(set v4i32:$XT, (bitconvert (v16i8 immAllOnesV)))]>;

We will get assert in PeepholeOptimizer.

```
llvm-lit llvm-project/llvm/test/CodeGen/PowerPC/build-vector-tests.ll -v

llvm-project/llvm/include/llvm/CodeGen/MachineInstr.h:417: const
llvm::MachineOperand &llvm::MachineInstr::getOperand(unsigned int)
const: Assertion `i < getNumOperands() && "getOperand() out of range!"'
failed.
```

The fix is to abort if we found out of bound access.

Reviewers: qcolombet, MatzeB, hfinkel, arsenm

Reviewed By: qcolombet

Subscribers: wdng, arsenm, steven.zhang, wuzish, nemanjai, hiraditya, kbarton, MaskRay, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65542

llvm-svn: 369261
2019-08-19 14:19:04 +00:00
David Stenberg 88df53e6ea [DebugInfo] Allow bundled calls in the MIR's call site info
Summary:
Extend the MIR parser and writer so that the call site information can
refer to calls that are bundled.

Reviewers: aprantl, asowda, NikolaPrica, djtodoro, ivanbaev, vsk

Reviewed By: aprantl

Subscribers: arsenm, hiraditya, llvm-commits

Tags: #debug-info, #llvm

Differential Revision: https://reviews.llvm.org/D66145

llvm-svn: 369256
2019-08-19 12:41:22 +00:00
Jeremy Morse 176bbd5cde [DebugInfo] Make postra sinking of DBG_VALUEs subregister-safe
Currently the machine instruction sinker identifies DBG_VALUE insts that
also need to sink by comparing register numbers. Unfortunately this isn't
safe, because (after register allocation) a DBG_VALUE may read a register
that aliases what's being sunk. To fix this, identify the DBG_VALUEs that
need to sink by recording & examining their register units. Register units
gives us the following guarantee:

  "Two registers overlap if and only if they have a common register unit"
  [MCRegisterInfo.h]

Thus we can always identify aliasing DBG_VALUEs if the set of register
units read by the DBG_VALUE, and the register units of the instruction
being sunk, intersect. (MachineSink already uses classes like
"LiveRegUnits" for determining sinking validity anyway).

The test added checks for super and subregister DBG_VALUE reads of a sunk
copy being sunk as well.

Differential Revision: https://reviews.llvm.org/D58191

llvm-svn: 369247
2019-08-19 09:53:07 +00:00
Craig Topper 74168ded03 [TargetLowering] Teach computeRegisterProperties to only widen v3i16/v3f16 vectors to the next power of 2 type if that's legal.
These were recently made simple types. This restores their
behavior back to something like their EVT legalization.

We might be able to fix the code in type legalization where the
assert was failing, but I didn't investigate too much as I had
already looked at the computeRegisterProperties code during the
review for v3i16/v3f16.

Most of the test changes restore the X86 codegen back to what
it looked like before the recent change. The test case in
vec_setcc.ll and is a reduced version of the reproducer from
the fuzzer.

Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=16490

llvm-svn: 369205
2019-08-18 06:28:06 +00:00
Craig Topper f43106e341 [SelectionDAG] Add a node creation debug message to getMachineNode.
llvm-svn: 369204
2019-08-18 06:28:00 +00:00
Kang Zhang b3d258fc44 [CodeGen] Do the Simple Early Return in block-placement pass to optimize the blocks
Summary:

Fix a bug of preducessors.

In `block-placement` pass, it will create some patterns for unconditional we can do the simple early retrun.
But the `early-ret` pass is before `block-placement`, we don't want to run it again.
This patch is to do the simple early return to optimize the blocks at the last of `block-placement`.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D63972

llvm-svn: 369191
2019-08-17 14:37:05 +00:00
Sanjay Patel acceedb15f [CodeGenPrepare] Fix use-after-free
If OptimizeExtractBits() encountered a shift instruction with no operands at all,
it would erase the instruction, but still return false.

This previously didn’t matter because its caller would always return after
processing the instruction, but https://reviews.llvm.org/D63233 changed the
function’s caller to fall through if it returned false, which would then cause
a use-after-free detectable by ASAN.

This change makes OptimizeExtractBits return true if it removes a shift
instruction with no users, terminating processing of the instruction.

Patch by: @brentdax (Brent Royal-Gordon)

Differential Revision: https://reviews.llvm.org/D66330

llvm-svn: 369168
2019-08-16 23:10:34 +00:00
Evgeniy Stepanov 187c63f145 Escape % in printf format string.
Fixes branch-relax-block-size.mir on the ASan builder.

llvm-svn: 369138
2019-08-16 18:23:54 +00:00
Amara Emerson c809230a69 [AArch64][GlobalISel] Lower G_SHUFFLE_VECTOR with 1 elt src and 1 elt mask.
Again, it's weird that these are allowed. Since lowering support was added in
r368709 we started crashing on compiling the neon intrinsics test in the test
suite. This fixes the lowering to fold the 1 elt src/mask case into copies.

llvm-svn: 369135
2019-08-16 18:06:53 +00:00
Guozhi Wei e03f6a1631 [CodeGen/Analysis] Intrinsic llvm.assume should not block tail call optimization
In function Analysis.cpp:isInTailCallPosition, instructions between call and ret are checked to see if they block tail call optimization. If an instruction is an intrinsic call, only llvm.lifetime_end is allowed and other intrinsic functions block tail call. When compiling tcmalloc, we found llvm.assume between a hot function call and ret, it blocks the optimization. But llvm.assume doesn't generate instructions, it should not block tail call.

Differential Revision: https://reviews.llvm.org/D66096

llvm-svn: 369125
2019-08-16 16:26:12 +00:00
Florian Hahn 403e85cbc5 Revert [CodeGen] Do the Simple Early Return in block-placement pass to optimize the blocks
This reverts r368997 (git commit 2a903c0b67)

It looks like this commit adds invalid predecessors to MBBs. The example
below fails the verifier after MachineBlockPlacement (run llc
-verify-machineinstrs):

@global.4 = external constant i8*

declare i32 @zot(...)

define i16* @snork.67() personality i8* bitcast (i32 (...)* @zot to i8*) {
bb:
  invoke void undef()
          to label %bb5 unwind label %bb4

bb4:                                              ; preds = %bb
  %tmp = landingpad { i8*, i32 }
          catch i8* null
  unreachable

bb5:                                              ; preds = %bb
  %tmp6 = load i32, i32* null, align 4
  %tmp7 = icmp eq i32 %tmp6, 0
  br i1 %tmp7, label %bb14, label %bb8

bb8:                                              ; preds = %bb11, %bb5
  invoke void undef()
          to label %bb9 unwind label %bb11

bb9:                                              ; preds = %bb8
  %tmp10 = invoke i16* undef()
          to label %bb14 unwind label %bb11

bb11:                                             ; preds = %bb9, %bb8
  %tmp12 = landingpad { i8*, i32 }
          cleanup
          catch i8* bitcast (i8** @global.4 to i8*)
  %tmp13 = icmp ult i64 undef, undef
  br i1 %tmp13, label %bb8, label %bb14

bb14:                                             ; preds = %bb11, %bb9, %bb5
  %tmp15 = phi i16* [ null, %bb5 ], [ null, %bb11 ], [ %tmp10, %bb9 ]
  ret i16* %tmp15
}

llvm-svn: 369104
2019-08-16 13:19:29 +00:00
Bjorn Pettersson 9dddd26e31 [DAGCombiner] Add simple folds for SMULFIX/UMULFIX/SMULFIXSAT
Summary:
Add the following DAGCombiner folds for mulfix being
one of SMULFIX/UMULFIX/SMULFIXSAT:
  (mulfix x, undef, scale) -> 0
  (mulfix x, 0, scale) -> 0

Also added canonicalization of constants to RHS.

Reviewers: RKSimon, craig.topper, spatel

Reviewed By: RKSimon

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66052

llvm-svn: 369103
2019-08-16 13:16:48 +00:00
Jeremy Morse 8b593480d3 [DebugInfo] Handle complex expressions with spills in LiveDebugValues
In r369026 we disabled spill-recognition in LiveDebugValues for anything
that has a complex expression. This is because it's hard to recover the
complex expression once the spill location is baked into it.

This patch re-enables spill-recognition and slightly adjusts the DBG_VALUE
insts that LiveDebugValues tracks: instead of tracking the last DBG_VALUE
for a variable, it tracks the last _unspilt_ DBG_VALUE. The spill-restore
code is then able to access and copy the original complex expression; but
the rest of LiveDebugValues has to be aware of the slight semantic shift,
and produce a new spilt location if a spilt location is propagated between
blocks.

The test added produces an incorrect variable location (see FIXME), which
will be the subject of future work.

Differential Revision: https://reviews.llvm.org/D65368

llvm-svn: 369092
2019-08-16 10:04:17 +00:00
Volkan Keles 0ae6006bee [GlobalISel] CSEMIRBuilder: Add support for G_GEP
Summary:
This patch adds G_GEP to `shouldCSEOpc` so that it can be CSEd. It also refactors
`translateGetElementPtr` by replacing `createGenericVirtualRegister` calls with types.

Reviewers: aditya_nandakumar, arsenm, dsanders, paquette, aemerson

Reviewed By: aditya_nandakumar

Subscribers: wdng, rovka, javed.absar, hiraditya, Petar.Avramovic, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66316

llvm-svn: 369070
2019-08-15 23:45:45 +00:00
Daniel Sanders 0c47611131 Apply llvm-prefer-register-over-unsigned from clang-tidy to LLVM
Summary:
This clang-tidy check is looking for unsigned integer variables whose initializer
starts with an implicit cast from llvm::Register and changes the type of the
variable to llvm::Register (dropping the llvm:: where possible).

Partial reverts in:
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
X86FixupLEAs.cpp - Some functions return unsigned and arguably should be MCRegister
X86FrameLowering.cpp - Some functions return unsigned and arguably should be MCRegister
HexagonBitSimplify.cpp - Function takes BitTracker::RegisterRef which appears to be unsigned&
MachineVerifier.cpp - Ambiguous operator==() given MCRegister and const Register
PPCFastISel.cpp - No Register::operator-=()
PeepholeOptimizer.cpp - TargetInstrInfo::optimizeLoadInstr() takes an unsigned&
MachineTraceMetrics.cpp - MachineTraceMetrics lacks a suitable constructor

Manual fixups in:
ARMFastISel.cpp - ARMEmitLoad() now takes a Register& instead of unsigned&
HexagonSplitDouble.cpp - Ternary operator was ambiguous between unsigned/Register
HexagonConstExtenders.cpp - Has a local class named Register, used llvm::Register instead of Register.
PPCFastISel.cpp - PPCEmitLoad() now takes a Register& instead of unsigned&

Depends on D65919

Reviewers: arsenm, bogner, craig.topper, RKSimon

Reviewed By: arsenm

Subscribers: RKSimon, craig.topper, lenary, aemerson, wuzish, jholewinski, MatzeB, qcolombet, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, wdng, nhaehnle, sbc100, jgravelle-google, kristof.beyls, hiraditya, aheejin, kbarton, fedor.sergeev, javed.absar, asb, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, tpr, PkmX, jocewei, jsji, Petar.Avramovic, asbirlea, Jim, s.egerton, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65962

llvm-svn: 369041
2019-08-15 19:22:08 +00:00
Matt Arsenault 1f2b727298 MVT: Add v3i16/v3f16 vectors
AMDGPU has some buffer intrinsics which theoretically could use
this. Some of the generated tables include the 3 and 4 element vector
versions of these rounded to 64-bits, which is ambiguous. Add these to
help the table disambiguate these.

Assertion change is for the path odd sized vectors now take for R600.
v3i16 is widened to v4i16, which then needs to be promoted to v4i32.

llvm-svn: 369038
2019-08-15 18:58:25 +00:00
Philip Reames d202899431 [NFC] Add a couple of dump routines for RegisterPressure helper classes
llvm-svn: 369037
2019-08-15 18:49:39 +00:00
Jeremy Morse c476124bc8 [DebugInfo] Avoid crash from dropped fragments in LiveDebugValues
This patch avoids a crash caused by DW_OP_LLVM_fragments being dropped
from DIExpressions by LiveDebugValues spill-restore code. The appearance
of a previously unseen fragment configuration confuses LDV, as documented
in PR42773, and reproduced by the test function this patch adds (Crashes
on a x86_64 debug build).

To avoid this, on spill restore, we now use fragment information from the
spilt-location-expression.

In addition, when spilling, we now don't spill any DBG_VALUE with a complex
expression, as it can't be safely restored and will definitely lead to an
incorrect variable location. The discussion of this is in D65368.

Differential Revision: https://reviews.llvm.org/D66284

llvm-svn: 369026
2019-08-15 17:49:46 +00:00
Jonas Devlieghere 0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00
Simon Pilgrim d4df81f463 Remove SmallBitVector.h include. NFCI.
SmallBitVector/BitVector types aren't used at all in the cpp file.

llvm-svn: 369008
2019-08-15 14:40:37 +00:00
Simon Pilgrim 983e9118a2 Remove BitVector.h include. NFCI.
BitVector type isn't used at all in the cpp file.

llvm-svn: 369007
2019-08-15 14:39:28 +00:00
Simon Pilgrim ed804dad1e [DAGCombine] MergeConsecutiveStores - fix cppcheck/MSVC extension warning. NFCI.
Set the StartIdx type to size_t so that it matches the StoreNodes SmallVector size() and index types.

Silences the MSVC analyzer warning that unsigned increment might overflow before exceeding size_t on 64-bit targets - this isn't likely to happen but it means we use consistent types and reduces the warning "noise" a little.

llvm-svn: 368998
2019-08-15 13:07:14 +00:00
Kang Zhang 2a903c0b67 [CodeGen] Do the Simple Early Return in block-placement pass to optimize the blocks
Summary:

This patch has trigger a bug of r368339, and the r368339 has been reverted, So upstream this patch again.

In `block-placement` pass, it will create some patterns for unconditional we can do the simple early retrun.
But the `early-ret` pass is before `block-placement`, we don't want to run it again.
This patch is to do the simple early return to optimize the blocks at the last of `block-placement`.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D63972

llvm-svn: 368997
2019-08-15 13:05:16 +00:00
Sanjay Patel 57d459309d [SDAG][x86] check for relaxed math when matching an FP reduction
If the last step in an FP add reduction allows reassociation and doesn't care
about -0.0, then we are free to recognize that computation as a reduction
that may reorder the intermediate steps.

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

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

llvm-svn: 368995
2019-08-15 12:43:15 +00:00
Florian Hahn de1d6c8220 Add ptrmask intrinsic
This patch adds a ptrmask intrinsic which allows masking out bits of a
pointer that must be zero when accessing it, because of ABI alignment
requirements or a restriction of the meaningful bits of a pointer
through the data layout.

This avoids doing a ptrtoint/inttoptr round trip in some cases (e.g. tagged
pointers) and allows us to not lose information about the underlying
object.

Reviewers: nlopes, efriedma, hfinkel, sanjoy, jdoerfert, aqjune

Reviewed by: sanjoy, jdoerfert

Differential Revision: https://reviews.llvm.org/D59065

llvm-svn: 368986
2019-08-15 10:12:26 +00:00
Craig Topper e7ea06b7d2 [SelectionDAGBuilder] Teach gather/scatter getUniformBase to look through vector zeroinitializer indices in addition to scalar zeroes.
llvm-svn: 368926
2019-08-14 21:38:56 +00:00
Sanjay Patel ecccf29e6c [SDAG] move variable closer to use; NFC
llvm-svn: 368905
2019-08-14 19:46:15 +00:00
Taewook Oh df7022825c [DebugInfo] Consider debug label scope has an extra lexical block file
Summary: There are places where a case that debug label scope has an extra lexical block file is not considered properly. The modified test won't pass without this patch.

Reviewers: aprantl, HsiangKai

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66187

llvm-svn: 368891
2019-08-14 17:58:45 +00:00
Jeremy Morse 90c2794bfc [DebugInfo] MCP: collect and update DBG_VALUEs encountered in local block
MCP currently uses changeDebugValuesDefReg / collectDebugValues to find
debug users of a register, however those functions assume that all
DBG_VALUEs immediately follow the specified instruction, which isn't
necessarily true. This is going to become very often untrue when we turn
off CodeGenPrepare::placeDbgValues.

Instead of calling changeDebugValuesDefReg on an instruction to change its
debug users, in this patch we instead collect DBG_VALUEs of copies as we
iterate over insns, and update the debug users of copies that are made
dead. This isn't a non-functional change, because MCP will now update
DBG_VALUEs that aren't immediately after a copy, but refer to the same
register. I've hijacked the regression test for PR38773 to test for this
new behaviour, an entirely new test seemed overkill.

Differential Revision: https://reviews.llvm.org/D56265

llvm-svn: 368835
2019-08-14 12:20:02 +00:00
Fangrui Song 8caa0aaa4d [AsmPrinter] Delete redundant .type foo, @function when emitting an ifunc
In MCAsmStreamer:

.type foo,@function   # <--- this is redundant
.type foo,@gnu_indirect_function

In MCELFStreamer, the latter STT_GNU_IFUNC overrides STT_FUNC.

llvm-svn: 368823
2019-08-14 10:30:27 +00:00
Aditya Nandakumar c65ac865c3 [GlobalISel]: Fix lowering of G_Shuffle_vector where we pick up the wrong source index
https://reviews.llvm.org/D66182

llvm-svn: 368781
2019-08-14 01:23:33 +00:00
Aditya Nandakumar 615eee6402 [GlobalISel]: Fix lowering of G_SHUFFLE_VECTOR with scalar sources
https://reviews.llvm.org/D66171

llvm-svn: 368753
2019-08-13 21:49:11 +00:00
Matt Arsenault 28215caa60 GlobalISel: Partially implement fewerElementsVector G_UNMERGE_VALUES
Odd sized vectors aren't handled yet.

llvm-svn: 368713
2019-08-13 16:26:28 +00:00
Matt Arsenault 690645bda0 GlobalISel: Implement lower for G_SHUFFLE_VECTOR
llvm-svn: 368709
2019-08-13 16:09:07 +00:00
Matt Arsenault 0a04a06250 GlobalISel: Add more verifier checks for G_SHUFFLE_VECTOR
llvm-svn: 368705
2019-08-13 15:52:21 +00:00
Matt Arsenault 5af9cf042f GlobalISel: Change representation of shuffle masks
Currently shufflemasks get emitted as any other constant, and you end
up with a bunch of virtual registers of G_CONSTANT with a
G_BUILD_VECTOR. The AArch64 selector then asserts on anything that
doesn't fit this pattern. This isn't an ideal representation, and
should avoid legalization and have fewer opportunities for a
representational error.

Rather than invent a new shuffle mask operand type, similar to what
ShuffleVectorSDNode does, just track the original IR Constant mask
operand. I don't completely like the idea of adding another link to
the IR, but MIR is already quite dependent on IR constants already,
and this will allow sharing the shuffle mask utility functions with
the IR.

llvm-svn: 368704
2019-08-13 15:34:38 +00:00
Roman Lebedev 676594305a [CodeGen][SelectionDAG] More efficient code for X % C == 0 (SREM case)
Summary:
This implements an optimization described in Hacker's Delight 10-17:
when `C` is constant, the result of `X % C == 0` can be computed
more cheaply without actually calculating the remainder.
The motivation is discussed here: https://bugs.llvm.org/show_bug.cgi?id=35479.

One huge caveat: this signed case is only valid for positive divisors.

While we can freely negate negative divisors, we can't negate `INT_MIN`,
so for now if `INT_MIN` is encountered, we bailout.
As a follow-up, it should be possible to handle that more gracefully
via extra `and`+`setcc`+`select`.

This passes llvm's test-suite, and from cursory(!) cross-examination
the folds (the assembly) match those of GCC, and manual checking via alive
did not reveal any issues (other than the `INT_MIN` case)

Reviewers: RKSimon, spatel, hermord, craig.topper, xbolva00

Reviewed By: RKSimon, xbolva00

Subscribers: xbolva00, thakis, javed.absar, hiraditya, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65366

llvm-svn: 368702
2019-08-13 14:57:37 +00:00
Roman Lebedev f4de7eda4a [TargetLowering][NFC] prepareUREMEqFold(): fixup comment
The comment initially matched the code, but the code was incorrect
and was fixed after the initial revert back back when it was introduced,
but the comment was never updated.

llvm-svn: 368701
2019-08-13 14:57:08 +00:00
Hans Wennborg 5390d25f2b Revert r368276 "[TargetLowering] SimplifyDemandedBits - call SimplifyMultipleUseDemandedBits for ISD::EXTRACT_VECTOR_ELT"
This introduced a false positive MemorySanitizer warning about use of
uninitialized memory in a vectorized crc function in Chromium. That suggests
maybe something is not right with this transformation. See
https://crbug.com/992853#c7 for a reproducer.

This also reverts the follow-up commits r368307 and r368308 which
depended on this.

> This patch attempts to peek through vectors based on the demanded bits/elt of a particular ISD::EXTRACT_VECTOR_ELT node, allowing us to avoid dependencies on ops that have no impact on the extract.
>
> In particular this helps remove some unnecessary scalar->vector->scalar patterns.
>
> The wasm shift patterns are annoying - @tlively has indicated that the wasm vector shift codegen are to be refactored in the near-term and isn't considered a major issue.
>
> Differential Revision: https://reviews.llvm.org/D65887

llvm-svn: 368660
2019-08-13 09:33:25 +00:00
Amara Emerson e14c91b71a [GlobalISel] Make the InstructionSelector instance non-const, allowing state to be maintained.
Currently we can't keep any state in the selector object that we get from
subtarget. As a result we have to plumb through all our variables through
multiple functions. This change makes it non-const and adds a virtual init()
method to allow further state to be captured for each target.

AArch64 makes use of this in this patch to cache a call to hasFnAttribute()
which is expensive to call, and is used on each selection of G_BRCOND.

Differential Revision: https://reviews.llvm.org/D65984

llvm-svn: 368652
2019-08-13 06:26:59 +00:00
Aditya Nandakumar 70fdfed45f [GlobalISel]: Add KnownBits for G_XOR
https://reviews.llvm.org/D66119

llvm-svn: 368648
2019-08-13 04:32:33 +00:00
Daniel Sanders a58a27513b Eliminate implicit Register->unsigned conversions in VirtRegMap. NFC
Summary:
This was mostly an experiment to assess the feasibility of completely
eliminating a problematic implicit conversion case in D61321 in advance of
landing that* but it also happens to align with the goal of propagating the
use of Register/MCRegister instead of unsigned so I believe it makes sense
to commit it.

The overall process for eliminating the implicit conversions from
Register/MCRegister -> unsigned was to:
1. Add an explicit conversion to support genuinely required conversions to
   unsigned. For example, using them as an index for IndexedMap. Sadly it's
   not possible to have an explicit and implicit conversion to the same
   type and only deprecate the implicit one so I called the explicit
   conversion get().
2. Temporarily annotate the implicit conversion to unsigned with
   LLVM_ATTRIBUTE_DEPRECATED to make them visible
3. Eliminate implicit conversions by propagating Register/MCRegister/
   explicit-conversions appropriately
4. Remove the deprecation added in 2.

* My conclusion is that it isn't feasible as there's too much code to
  update in one go.

Depends on D65678

Reviewers: arsenm

Subscribers: MatzeB, wdng, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65685

llvm-svn: 368643
2019-08-13 00:55:24 +00:00