Commit Graph

24884 Commits

Author SHA1 Message Date
Simon Pilgrim 72b324de4d [TargetLowering] Add BuildSDiv support for division by one or negone.
This reduces most of the sdiv stages (the MULHS, shifts etc.) to just zero/identity values and use the numerator scale factor to multiply by +1/-1.

llvm-svn: 340260
2018-08-21 10:20:36 +00:00
Bjorn Pettersson 880f291577 [RegisterCoalescer] Do not assert when trying to remat dead values
Summary:
RegisterCoalescer::reMaterializeTrivialDef used to assert that
the input register was live in. But as shown by the new
coalesce-dead-lanes.mir test case that seems to be a valid
scenario. We now return false instead of the assert, simply
avoiding to remat the dead def.

Normally a COPY of an undef value is eliminated by
eliminateUndefCopy(). Although we only do that when the
destination isn't a physical register. So the situation
above should be limited to the case when we copy an undef
value to a physical register.

Reviewers: kparzysz, wmi, tpr

Reviewed By: kparzysz

Subscribers: MatzeB, qcolombet, tpr, llvm-commits

Differential Revision: https://reviews.llvm.org/D50842

llvm-svn: 340255
2018-08-21 07:49:05 +00:00
Krzysztof Parzyszek cc3f630252 Consistently use MemoryLocation::UnknownSize to indicate unknown access size
1. Change the software pipeliner to use unknown size instead of dropping
   memory operands. It used to do it before, but MachineInstr::mayAlias
   did not handle it correctly.
2. Recognize UnknownSize in MachineInstr::mayAlias.
3. Print and parse UnknownSize in MIR.

Differential Revision: https://reviews.llvm.org/D50339

llvm-svn: 340208
2018-08-20 20:37:57 +00:00
Cameron McInally 94b9029be9 [FPEnv] Support constrained FREM intrinsic
Differential Revision: https://reviews.llvm.org/D50975

llvm-svn: 340201
2018-08-20 19:28:56 +00:00
Marcello Maggioni 5ca4128b45 [PSV] Update API to be able to use TargetCustom without UB.
getTargetCustom() requires values for "Kind" in the constructor
that are not in the PSVKind enum. Passing a value that is not inside
an enum as an argument to a constructor of the type of the enum is
UB. Changing to the underlying type of the enum would solve the UB

Differential Revision: https://reviews.llvm.org/D50909

llvm-svn: 340200
2018-08-20 19:23:45 +00:00
Aditya Nandakumar 2a08285cf3 Revert "Revert r339977: [GISel]: Add Opcodes for a few LLVM Intrinsics"
This reverts commit 7debc334e6421bb5251ef8f18e97166dfc7dd787.

I missed updating legalizer-info-validation.mir as I had assertions
turned off in my build and that specific test requires asserts. Fixed it
now.

llvm-svn: 340197
2018-08-20 18:43:19 +00:00
Simon Pilgrim 6ac905926f [TargetLowering] Disable BuildSDiv division by one or negone.
Fuzz tests have detected an issue, currently working on a fix.

llvm-svn: 340195
2018-08-20 18:23:54 +00:00
Reid Kleckner 918930adf9 Revert rr340111 "[GISel]: Add Legalization/lowering code for bit counting operations"
It causes LegalizerHelperTest.LowerBitCountingCTTZ1 to fail.

llvm-svn: 340186
2018-08-20 16:50:19 +00:00
Simon Pilgrim 1a00042270 [SelectionDAG] Reuse the Op's VT. NFCI.
llvm-svn: 340173
2018-08-20 13:44:03 +00:00
Simon Pilgrim 5b78c9d58d [SelectionDAG] Add partial sign-bit support to ComputeNumSignBits for BITCAST nodes
Only adds support to the existing 'large element' scalar/vector to 'small element' vector bitcasts.

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

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

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

llvm-svn: 340143
2018-08-19 17:47:50 +00:00
Hsiangkai Wang 68c706ceb7 [DebugInfo] In FastISel, convert llvm.dbg.label to DBG_LABEL MI.
Convert llvm.dbg.label(!label_metadata) to DBG_LABEL !label_metadata.

Differential Revision: https://reviews.llvm.org/D50622

llvm-svn: 340122
2018-08-18 14:55:34 +00:00
Craig Topper cc5dbbf759 [DAGCombiner] Allow divide by constant optimization on opaque constants.
Summary:
I believe this restores the behavior we had before r339147.

Fixes PR38622.

Reviewers: RKSimon, chandlerc, spatel

Reviewed By: chandlerc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50936

llvm-svn: 340120
2018-08-18 05:52:42 +00:00
Aditya Nandakumar 59b2485ba2 [GISel]: Add Legalization/lowering code for bit counting operations
https://reviews.llvm.org/D48847#inline-448257

Ported legalization expansions for CTLZ/CTTZ from DAG to GISel.

Reviewed by rtereshin.

llvm-svn: 340111
2018-08-18 00:01:54 +00:00
Matt Arsenault 25e51540e1 DAG: Fix isKnownNeverNaN for basic non-sNaN cases
fadd/fsub/fmul need to worry about infinities as well
as fdiv.

llvm-svn: 340085
2018-08-17 21:19:22 +00:00
Hsiangkai Wang 2532ac880a [DebugInfo] Generate DWARF debug information for labels. (Fix leak problems)
There are two forms for label debug information in DWARF format.

1. Labels in a non-inlined function:

DW_TAG_label
  DW_AT_name
  DW_AT_decl_file
  DW_AT_decl_line
  DW_AT_low_pc

2. Labels in an inlined function:

DW_TAG_label
  DW_AT_abstract_origin
  DW_AT_low_pc

We will collect label information from DBG_LABEL. Before every DBG_LABEL,
we will generate a temporary symbol to denote the location of the label.
The symbol could be used to get DW_AT_low_pc afterwards. So, we create a
mapping between 'inlined label' and DBG_LABEL MachineInstr in DebugHandlerBase.
The DBG_LABEL in the mapping is used to query the symbol before it.

The AbstractLabels in DwarfCompileUnit is used to process labels in inlined
functions.

We also keep a mapping between scope and labels in DwarfFile to help to
generate correct tree structure of DIEs.

It also generates label debug information under global isel.

Differential Revision: https://reviews.llvm.org/D45556

llvm-svn: 340039
2018-08-17 15:22:04 +00:00
Alex Bradbury 3291f9aa81 [AtomicExpandPass] Widen partword atomicrmw or/xor/and before tryExpandAtomicRMW
This patch performs a widening transformation of bitwise atomicrmw 
{or,xor,and} and applies it prior to tryExpandAtomicRMW. This operates 
similarly to convertCmpXchgToIntegerType. For these operations, the i8/i16 
atomicrmw can be implemented in terms of the 32-bit atomicrmw by appropriately 
manipulating the operands. There is no functional change for the handling of 
partword or/xor, but the transformation for partword 'and' is new.

The advantage of performing this transformation early is that the same 
code-path can be used regardless of the approach used to expand the atomicrmw 
(AtomicExpansionKind). i.e. the same logic is used for 
AtomicExpansionKind::CmpXchg and can also be used by the intrinsic-based 
expansion in D47882.

Differential Revision: https://reviews.llvm.org/D48129

llvm-svn: 340027
2018-08-17 14:03:37 +00:00
Simon Pilgrim 03e57521c0 [DAGCombiner] extractShiftForRotate - fix out of range shift issue
Don't just check for negative shift amounts.

Fixes OSS Fuzz #9935
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=9935

llvm-svn: 340015
2018-08-17 12:25:18 +00:00
Simon Pilgrim 5113b48798 [DAGCombine] Improve (sra (sra x, c1), c2) -> (sra x, (add c1, c2)) folding
Add support for cases where only some c1+c2 results exceed the max bitshift, clamping accordingly.

Differential Revision: https://reviews.llvm.org/D35722

llvm-svn: 340010
2018-08-17 10:52:49 +00:00
Simon Pilgrim 22d580f2ca Fix "control reaches end of non-void function" -Wreturn-type warning. NFCI.
llvm-svn: 340006
2018-08-17 09:47:52 +00:00
Chen Zheng e2d47dd1bb [MISC]Fix wrong usage of std::equal()
Differential Revision: https://reviews.llvm.org/D49958

llvm-svn: 340000
2018-08-17 07:51:01 +00:00
Chandler Carruth b898b86f49 Revert r339977: [GISel]: Add Opcodes for a few LLVM Intrinsics
This is breaking ~all the bots.

llvm-svn: 339982
2018-08-17 04:47:16 +00:00
Aditya Nandakumar 973a557338 [GISel]: Add Opcodes for a few LLVM Intrinsics
https://reviews.llvm.org/D50401

Add opcodes for llvm.intrinsic.trunc, round, and update the IRTranslator
for the same.

Reviewed by: dsanders.

llvm-svn: 339977
2018-08-17 01:41:56 +00:00
David Blaikie 0e03047e85 DebugInfo: Remove command line (& target-based) disabling of pubnames in favor of metadata
Now that Clang disables NVPTX pubnames via metadata there's no need for
this fallback to target detection in the backend.

llvm-svn: 339970
2018-08-16 23:57:15 +00:00
Chandler Carruth 75ca6be1c1 [x86/MIR] Implement support for pre- and post-instruction symbols, as
well as MIR parsing support for `MCSymbol` `MachineOperand`s.

The only real way to test pre- and post-instruction symbol support is to
use them in operands, so I ended up implementing that within the patch
as well. I can split out the operand support if folks really want but it
doesn't really seem worth it.

The functional implementation of pre- and post-instruction symbols is
now *completely trivial*. Two tiny bits of code in the (misnamed)
AsmPrinter. It should be completely target independent as well. We emit
these exactly the same way as we emit basic block labels. Most of the
code here is to give full dumping, MIR printing, and MIR parsing support
so that we can write useful tests.

The MIR parsing of MC symbol operands still isn't 100%, as it forces the
symbols to be non-temporary and non-local symbols with names. However,
those names often can encode most (if not all) of the special semantics
desired, and unnamed symbols seem especially annoying to serialize and
de-serialize. While this isn't perfect or full support, it seems plenty
to write tests that exercise usage of these kinds of operands.

The MIR support for pre-and post-instruction symbols was quite
straightforward. I chose to print them out in an as-if-operand syntax
similar to debug locations as this seemed the cleanest way and let me
use nice introducer tokens rather than inventing more magic punctuation
like we use for memoperands.

However, supporting MIR-based parsing of these symbols caused me to
change the design of the symbol support to allow setting arbitrary
symbols. Without this, I don't see any reasonable way to test things
with MIR.

Differential Revision: https://reviews.llvm.org/D50833

llvm-svn: 339962
2018-08-16 23:11:05 +00:00
Craig Topper 883ff69c93 [DAGCombiner] Don't reassociate operations that have the vector reduction flag set.
When nodes are reassociated the vector-reduction flag gets lost.

The test case is here is what would happen if you had a sum of absolute differences loop that started with a non-zero but contant sum and that loop was unrolled. The vectorizer will generate a constant vector for the initial value. And DAGCombiner reassociate tries to move it down the addition tree erasing the vector-reduction flag. Interestingly this moves constants the opposite direction of the reassociate IR pass.

I've chosen to just punt on the reassociate, but I suppose we could maybe preserve the flag if both nodes have it set.

Differential Revision: https://reviews.llvm.org/D50827

llvm-svn: 339946
2018-08-16 21:54:05 +00:00
Chandler Carruth c73c0307fe [MI] Change the array of `MachineMemOperand` pointers to be
a generically extensible collection of extra info attached to
a `MachineInstr`.

The primary change here is cleaning up the APIs used for setting and
manipulating the `MachineMemOperand` pointer arrays so chat we can
change how they are allocated.

Then we introduce an extra info object that using the trailing object
pattern to attach some number of MMOs but also other extra info. The
design of this is specifically so that this extra info has a fixed
necessary cost (the header tracking what extra info is included) and
everything else can be tail allocated. This pattern works especially
well with a `BumpPtrAllocator` which we use here.

I've also added the basic scaffolding for putting interesting pointers
into this, namely pre- and post-instruction symbols. These aren't used
anywhere yet, they're just there to ensure I've actually gotten the data
structure types correct. I'll flesh out support for these in
a subsequent patch (MIR dumping, parsing, the works).

Finally, I've included an optimization where we store any single pointer
inline in the `MachineInstr` to avoid the allocation overhead. This is
expected to be the overwhelmingly most common case and so should avoid
any memory usage growth due to slightly less clever / dense allocation
when dealing with >1 MMO. This did require several ergonomic
improvements to the `PointerSumType` to reasonably support the various
usage models.

This also has a side effect of freeing up 8 bits within the
`MachineInstr` which could be repurposed for something else.

The suggested direction here came largely from Hal Finkel. I hope it was
worth it. ;] It does hopefully clear a path for subsequent extensions
w/o nearly as much leg work. Lots of thanks to Reid and Justin for
careful reviews and ideas about how to do all of this.

Differential Revision: https://reviews.llvm.org/D50701

llvm-svn: 339940
2018-08-16 21:30:05 +00:00
David Blaikie 66cf14d06b DebugInfo: Add metadata support for disabling DWARF pub sections
In cases where the debugger load time is a worthwhile tradeoff (or less
costly - such as loading from a DWP instead of a variety of DWOs
(possibly over a high-latency/distributed filesystem)) against object
file size, it can be reasonable to disable pubnames and corresponding
gdb-index creation in the linker.

A backend-flag version of this was implemented for NVPTX in
D44385/r327994 - which was fine for NVPTX which wouldn't mix-and-match
CUs. Now that it's going to be a user-facing option (likely powered by
"-gno-pubnames", the same as GCC) it should be encoded in the
DICompileUnit so it can vary per-CU.

After this, likely the NVPTX support should be migrated to the metadata
& the previous flag implementation should be removed.

Reviewers: aprantl

Differential Revision: https://reviews.llvm.org/D50213

llvm-svn: 339939
2018-08-16 21:29:55 +00:00
Krzysztof Parzyszek 9af86a5e01 [MachineVerifier] Check if predecessor is jointly dominated by undefs
Each use of a value should be jointly dominated by the union of defs and
undefs. It can happen that it will only be jointly dominated by undefs,
and that is still legal. Make sure that the verifier is aware of that.

llvm-svn: 339924
2018-08-16 19:13:28 +00:00
Eli Friedman 73e8a784e6 [SelectionDAG] Improve the legalisation lowering of UMULO.
There is no way in the universe, that doing a full-width division in
software will be faster than doing overflowing multiplication in
software in the first place, especially given that this same full-width
multiplication needs to be done anyway.

This patch replaces the previous implementation with a direct lowering
into an overflowing multiplication algorithm based on half-width
operations.

Correctness of the algorithm was verified by exhaustively checking the
output of this algorithm for overflowing multiplication of 16 bit
integers against an obviously correct widening multiplication. Baring
any oversights introduced by porting the algorithm to DAG, confidence in
correctness of this algorithm is extremely high.

Following table shows the change in both t = runtime and s = space. The
change is expressed as a multiplier of original, so anything under 1 is
“better” and anything above 1 is worse.

+-------+-----------+-----------+-------------+-------------+
| Arch  | u64*u64 t | u64*u64 s | u128*u128 t | u128*u128 s |
+-------+-----------+-----------+-------------+-------------+
|   X64 |     -     |     -     |    ~0.5     |    ~0.64    |
|  i686 |   ~0.5    |   ~0.6666 |    ~0.05    |    ~0.9     |
| armv7 |     -     |   ~0.75   |      -      |    ~1.4     |
+-------+-----------+-----------+-------------+-------------+

Performance numbers have been collected by running overflowing
multiplication in a loop under `perf` on two x86_64 (one Intel Haswell,
other AMD Ryzen) based machines. Size numbers have been collected by
looking at the size of function containing an overflowing multiply in
a loop.

All in all, it can be seen that both performance and size has improved
except in the case of armv7 where code size has regressed for 128-bit
multiply. u128*u128 overflowing multiply on 32-bit platforms seem to
benefit from this change a lot, taking only 5% of the time compared to
original algorithm to calculate the same thing.

The final benefit of this change is that LLVM is now capable of lowering
the overflowing unsigned multiply for integers of any bit-width as long
as the target is capable of lowering regular multiplication for the same
bit-width. Previously, 128-bit overflowing multiply was the widest
possible.

Patch by Simonas Kazlauskas!

Differential Revision: https://reviews.llvm.org/D50310

llvm-svn: 339922
2018-08-16 18:39:39 +00:00
Krzysztof Parzyszek 17143f6111 [RegisterCoalescer] Shrink to uses if needed after removeCopyByCommutingDef
llvm-svn: 339912
2018-08-16 18:02:59 +00:00
Simon Pilgrim 87d0039a45 [TargetLowering] Add support for non-uniform vectors to BuildSDIV
This patch refactors the existing TargetLowering::BuildSDIV base implementation to support non-uniform constant vector denominators.

This is the last patch necessary to close PR36545

Differential Revision: https://reviews.llvm.org/D50765

llvm-svn: 339908
2018-08-16 17:44:33 +00:00
Simon Pilgrim ede4905375 [TargetLowering] Refactor BuildSDIV in preparation for D50765. NFCI.
Pull out magic factor calculators into a helper function, use 0/+1/-1 multiplication factor to (optionally) add/sub the numerator.

llvm-svn: 339898
2018-08-16 16:54:06 +00:00
Guozhi Wei 8c17f9a77d [CodeGenPrepare] Add BothExtension type to PromotedInsts
This patch fixes PR38125.

Instruction extension types are recorded in PromotedInsts, it can be used later in function canGetThrough. If an instruction has two users with different extension types, it will be inserted into PromotedInsts two times in function promoteOperandForOther. The second one overwrites the first one, and the final extension type is wrong, later causes problem in canGetThrough.

This patch changes the simple bool extension type to 2-bit enum type, add a BothExtension type in addition to zero/sign extension. When an user sees BothExtension for an instruction, it actually knows nothing about how that instruction is extended.

Differential Revision: https://reviews.llvm.org/D49512

llvm-svn: 339822
2018-08-15 22:08:26 +00:00
Matt Arsenault 0f2c1cf429 DAG: Use getObjectOffset helper
llvm-svn: 339813
2018-08-15 21:03:44 +00:00
Matt Arsenault 22f01268fe DAG: Try to custom lower when promoting float operands
For some reason this wasn't done for floats like
integers.

llvm-svn: 339811
2018-08-15 20:34:54 +00:00
Krzysztof Parzyszek 3b097b4d3e [RegisterCoalescer] Ensure that both registers have subranges if one does
llvm-svn: 339792
2018-08-15 17:04:58 +00:00
Krzysztof Parzyszek 88d267d094 [RegisterCoalescer] Reset VNInfo def when copying segments over
llvm-svn: 339788
2018-08-15 16:21:53 +00:00
Krzysztof Parzyszek 46ce441df6 [RegAlloc] Check that subreg liveness tracking applies to given virtual reg
Subregister liveness applies selectively to register classes with certain
properties. Make sure that when it's enabled, it applies to a given virtual
register (in virtual register rewriter).

llvm-svn: 339784
2018-08-15 16:07:47 +00:00
Simon Pilgrim 4b2317ebfb [TargetLowering] Minor cleanup of TargetLowering::BuildSDIV. NFCI.
Pull out some types to match layout in TargetLowering::BuildUDIV. Early step towards adding non-uniform vector support.

llvm-svn: 339763
2018-08-15 11:11:05 +00:00
Simon Pilgrim a4ba43d3d3 [TargetLowering] Minor refactor to TargetLowering::BuildUDIV to merge scalar/vector magic value collection. NFCI.
Use the same ISD::matchUnaryPredicate pattern that was used in D50392.

llvm-svn: 339758
2018-08-15 10:11:13 +00:00
Simon Pilgrim e8a906ba47 [DagCombiner] Don't bother adding to the work list if TLI.BuildSDIVPow2 failed. NFCI.
Matches the code in BuildSDIV/BuildUDIV

llvm-svn: 339757
2018-08-15 10:02:54 +00:00
Simon Pilgrim a272fa9b0c [TargetLowering] Add support for non-uniform vectors to BuildExactSDIV
This patch refactors the existing BuildExactSDIV implementation to support non-uniform constant vector denominators.

Differential Revision: https://reviews.llvm.org/D50392

llvm-svn: 339756
2018-08-15 09:35:12 +00:00
Chandler Carruth 66654b72c9 [SDAG] Remove the reliance on MI's allocation strategy for
`MachineMemOperand` pointers attached to `MachineSDNodes` and instead
have the `SelectionDAG` fully manage the memory for this array.

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

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

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

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

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

llvm-svn: 339740
2018-08-14 23:30:32 +00:00
Cameron McInally 00b0658aae [FPEnv] Scalarize StrictFP vector operations
Add a helper function to scalarize constrained FP operations as needed.

Differential Revision: https://reviews.llvm.org/D50720

llvm-svn: 339735
2018-08-14 22:13:11 +00:00
Eli Friedman 0d12e90bf5 [ARM] Make PerformSHLSimplify add nodes to the DAG worklist correctly.
Intentionally excluding nodes from the DAGCombine worklist is likely to
lead to weird optimizations and infinite loops, so it's generally a bad
idea.

To avoid the infinite loops, fix DAGCombine to use the
isDesirableToCommuteWithShift target hook before performing the
transforms in question, and implement the target hook in the ARM backend
disable the transforms in question.

Fixes https://bugs.llvm.org/show_bug.cgi?id=38530 . (I don't have a
reduced testcase for that bug. But we should have sufficient test
coverage for PerformSHLSimplify given that we're not playing weird
tricks with the worklist. I can try to bugpoint it if necessary,
though.)

Differential Revision: https://reviews.llvm.org/D50667

llvm-svn: 339734
2018-08-14 22:10:25 +00:00
Adrian Prantl 55f4262999 [DebugInfoMetadata] Added DIFlags interface in DIBasicType.
Flags in DIBasicType will be used to pass attributes used in
DW_TAG_base_type, such as DW_AT_endianity.

Patch by Chirag Patel!

Differential Revision: https://reviews.llvm.org/D49610

llvm-svn: 339714
2018-08-14 19:35:34 +00:00
Bruno Cardoso Lopes f446282aad Revert "[DebugInfo] Generate DWARF debug information for labels. (Fix leak problems)"
This reverts commit cb8c5e417d55141f3f079a8a876e786f44308336 / r339676.

This causing a test to fail in http://green.lab.llvm.org/green/job/clang-stage1-configure-RA/48406/

    LLVM :: DebugInfo/Generic/debug-label.ll

llvm-svn: 339700
2018-08-14 17:54:41 +00:00
Nirav Dave fbfe2ad9e0 [DAG] Avoid redundant chain transversal in store merge cycle check. NFCI.
Patch by Henric Karlsson.

llvm-svn: 339688
2018-08-14 16:20:43 +00:00
Hsiangkai Wang ccae278938 [DebugInfo] Generate DWARF debug information for labels. (Fix leak problems)
There are two forms for label debug information in DWARF format.

1. Labels in a non-inlined function:

DW_TAG_label
  DW_AT_name
  DW_AT_decl_file
  DW_AT_decl_line
  DW_AT_low_pc

2. Labels in an inlined function:

DW_TAG_label
  DW_AT_abstract_origin
  DW_AT_low_pc

We will collect label information from DBG_LABEL. Before every DBG_LABEL,
we will generate a temporary symbol to denote the location of the label.
The symbol could be used to get DW_AT_low_pc afterwards. So, we create a
mapping between 'inlined label' and DBG_LABEL MachineInstr in DebugHandlerBase.
The DBG_LABEL in the mapping is used to query the symbol before it.

The AbstractLabels in DwarfCompileUnit is used to process labels in inlined
functions.

We also keep a mapping between scope and labels in DwarfFile to help to
generate correct tree structure of DIEs.

It also generates label debug information under global isel.

Differential Revision: https://reviews.llvm.org/D45556

llvm-svn: 339676
2018-08-14 13:50:59 +00:00
Amara Emerson 30e61404a8 [GlobalISel][IRTranslator] Fix a bug in handling repeating struct types during argument lowering.
Differential Revision: https://reviews.llvm.org/D49442

llvm-svn: 339674
2018-08-14 12:04:25 +00:00
Scott Linder 35213793bc [CodeGen] Fix assert in SelectionDAG::computeKnownBits
Fix SelectionDAG::computeKnownBits asserting when handling EXTRACT_SUBVECTOR
when zero extending the demanded elements mask if it is already as long as the
source vector.

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

llvm-svn: 339600
2018-08-13 18:44:21 +00:00
Simon Pilgrim 26e3d3f1c8 [DAGCombiner] simplifyDivRem - add comment describing divide by undef/zero combine. NFC.
llvm-svn: 339561
2018-08-13 13:12:25 +00:00
Simon Pilgrim ee82a79041 [CGP] Fix GEP issue with out of range APInt constant values not fitting in int64_t
Test case reduced from https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=7173

llvm-svn: 339556
2018-08-13 12:10:09 +00:00
Craig Topper cacf12a149 [SelectionDAG] In PromoteFloatOp_BITCAST, insert a bitcast after the fp_to_fp16 in case the result type isn't a scalar integer.
This is another variation of PR38533. In this case, the result type of the bitcast is legal and 16-bits wide, but not a scalar integer. So we need to emit the convert to i16 and then bitcast it to the true result type. This new bitcast will be further type legalized if necessary.

llvm-svn: 339536
2018-08-13 06:53:49 +00:00
Craig Topper e42a159537 [SelectionDAG] In PromoteIntRes_BITCAST, when the input is TypePromoteFloat, make sure the output type is scalar. For vectors, use a store and load of temporary.
Previously if the result type was a vector, we emitted a FP_TO_FP16 with a vector result type which isn't valid.

This is basically the opposite case of the root cause of PR38533.

llvm-svn: 339535
2018-08-13 06:53:47 +00:00
Lei Liu 901a0a9588 Restore correct x86_64 EH encodings in kernel code model
Fixes PR37524.

The exception handling encodings for x86_64 in kernel code model
has been changed with r309884.  Restore it to correct ones.  These
encodings include PersonalityEncoding, LSDAEncoding and
TTypeEncoding.

Differential Revision: https://reviews.llvm.org/D50490

llvm-svn: 339534
2018-08-13 06:06:53 +00:00
Craig Topper 42e32117bb [SelectionDAG] In PromoteFloatRes_BITCAST, insert a bitcast before the fp16_to_fp in case the input type isn't an i16.
The bitcast can be further legalized as needed.

Fixes PR38533.

llvm-svn: 339533
2018-08-13 05:26:49 +00:00
Matt Arsenault 1201301b94 DAG: Check no-signed-zeros instead of unsafe-fp-math
Addresses fixme, although this should still be checking individual
operand flags.

llvm-svn: 339525
2018-08-12 19:09:12 +00:00
Craig Topper 60177f1aee [TargetLowering] Simplify one of the special cases in SimplifyDemandedBits for XOR. NFCI
We were checking for all bits being Known by checking Known.Zero|Known.One, but if all the bits are known then the value should be a Constant and we can just check for that instead.

llvm-svn: 339509
2018-08-12 06:52:03 +00:00
Craig Topper d112206004 [TargetLowering] Use APInt::isSubsetOf to simplify some code. NFC
llvm-svn: 339508
2018-08-12 05:34:15 +00:00
Hans Wennborg d4090be340 Rename the cfguard module flag to cfguardtable
The previous name sounds like it inserts cfguard implementation, but it
really just emits the table of address-taken functions. Change the name
to better reflect that.

Clang will be updated in the next commit.

llvm-svn: 339419
2018-08-10 09:48:53 +00:00
Reid Kleckner fce7f73bec [MC] Move EH DWARF encodings from MC to CodeGen, NFC
Summary:
The TType encoding, LSDA encoding, and personality encoding are all
passed explicitly by CodeGen to the assembler through .cfi_* directives,
so only the AsmPrinter needs to know about them.

The FDE CFI encoding however, controls the encoding of the label
implicitly created by the .cfi_startproc directive. That directive seems
to be special in that it doesn't take an encoding, so the assembler just
has to know how to encode one DSO-local label reference from .eh_frame
to .text.

As a result, it looks like MC will continue to have to know when the
large code model is in use. Perhaps we could invent a '.cfi_startproc
[large]' flag so that this knowledge doesn't need to pollute the
assembler.

Reviewers: davide, lliu0, JDevlieghere

Subscribers: hiraditya, fedor.sergeev, llvm-commits

Differential Revision: https://reviews.llvm.org/D50533

llvm-svn: 339397
2018-08-09 22:24:04 +00:00
Sanjay Patel 15d1501aae [SelectionDAG] try harder to convert funnel shift to rotate
Similar to rL337966 - if the DAGCombiner's rotate matching was 
working as expected, I don't think we'd see any test diffs here.

AArch only goes right, and PPC only goes left. 
x86 has both, so no diffs there.

Differential Revision: https://reviews.llvm.org/D50091

llvm-svn: 339359
2018-08-09 17:26:22 +00:00
Michael Berg ca38254601 extend folding fsub/fadd to fneg for FMF
Summary: This change provides a common optimization path for both Unsafe and FMF driven optimization for this fsub fold adding reassociation, as it the flag that most closely represents the translation

Reviewers: spatel, wristow, arsenm

Reviewed By: spatel

Subscribers: wdng

Differential Revision: https://reviews.llvm.org/D50195

llvm-svn: 339357
2018-08-09 17:00:03 +00:00
Bjorn Pettersson c8b782cec2 [MC] Remove PhysRegSize from MCRegisterClass
Summary:
The interface to get size and spill size of a register
was moved from MCRegisterInfo to TargetRegisterInfo over
a year ago. Afaik the old interface has bee around
to give out-of-tree targets a chance to adapt to the
new interface.

One problem with the old MCRegisterClass::PhysRegSize was that
it represented the size of a register as "size in bits" / 8.
So a register had to be a multiple of eight bits wide for the
size to be correct (and the byte size for the target needed to
be eight bits).

Reviewers: kparzysz, qcolombet

Reviewed By: kparzysz

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47199

llvm-svn: 339350
2018-08-09 15:19:07 +00:00
Simon Pilgrim a9f95429d9 [TargetLowering] Add BuildSDIVPattern helper to BuildExactSDIV (NFCI).
As requested in D50392, pull the magic constant calculations out into a helper function.

llvm-svn: 339346
2018-08-09 13:56:04 +00:00
Sanjay Patel e47dc1a405 [DAGCombiner] loosen constraints for fsub+fadd fold
isNegatibleForFree() should not matter here (as the test diffs show)
because it's always a win to replace an fsub+fadd with fneg. The
problem in D50195 persists because either (1) we are doing these
folds in the wrong order or (2) we're missing another fold for fadd.

llvm-svn: 339299
2018-08-08 23:04:43 +00:00
Sanjay Patel e327266d45 [DAGCombiner] move fadd simplification ahead of other folds
I don't know if it's possible to expose this diff in a test,
but we should always try simplifications (no new nodes created)
before more complicated transforms for efficiency (similar to
what we do in IR).

llvm-svn: 339298
2018-08-08 22:46:30 +00:00
Ties Stuij 083fb1a25c revert '[CodeGen] emit inline asm clobber list warnings for reserved'
llvm-svn: 339274
2018-08-08 17:11:54 +00:00
Jonas Devlieghere caacedb03e [DebugInfo] Fine tune emitting flags as part of the producer
When using APPLE extensions, don't duplicate the compiler invocation's
flags both in AT_producer and AT_APPLE_flags.

Differential revision: https://reviews.llvm.org/D50453

llvm-svn: 339268
2018-08-08 16:33:22 +00:00
Simon Pilgrim 4d4220fa2a [DAG] DAGCombiner::visitSDIVLike - remove unnecessary isConstOrConstSplat call. NFCI.
The isConstOrConstSplat result is only used in a ISD::matchUnaryPredicate call which can perform the equivalent iteration just as quickly.

llvm-svn: 339262
2018-08-08 15:37:52 +00:00
Ties Stuij 52f3631f4b [CodeGen] emit inline asm clobber list warnings for reserved
Summary:
Currently, in line with GCC, when specifying reserved registers like sp or pc on an inline asm() clobber list, we don't always preserve the original value across the statement. And in general, overwriting reserved registers can have surprising results.

For example:


```
extern int bar(int[]);

int foo(int i) {
  int a[i]; // VLA
  asm volatile(
      "mov r7, #1"
    :
    :
    : "r7"
  );

  return 1 + bar(a);
}
```

Compiled for thumb, this gives:
```
$ clang --target=arm-arm-none-eabi -march=armv7a -c test.c -o - -S -O1 -mthumb
...
foo:
        .fnstart
@ %bb.0:                                @ %entry
        .save   {r4, r5, r6, r7, lr}
        push    {r4, r5, r6, r7, lr}
        .setfp  r7, sp, #12
        add     r7, sp, #12
        .pad    #4
        sub     sp, #4
        movs    r1, #7
        add.w   r0, r1, r0, lsl #2
        bic     r0, r0, #7
        sub.w   r0, sp, r0
        mov     sp, r0
        @APP
        mov.w   r7, #1
        @NO_APP
        bl      bar
        adds    r0, #1
        sub.w   r4, r7, #12
        mov     sp, r4
        pop     {r4, r5, r6, r7, pc}
...
```

r7 is used as the frame pointer for thumb targets, and this function needs to restore the SP from the FP because of the variable-length stack allocation a. r7 is clobbered by the inline assembly (and r7 is included in the clobber list), but LLVM does not preserve the value of the frame pointer across the assembly block.

This type of behavior is similar to GCC's and has been discussed on the bugtracker: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=11807 . No consensus seemed to have been reached on the way forward.  Clang behavior has briefly been discussed on the CFE mailing (starting here: http://lists.llvm.org/pipermail/cfe-dev/2018-July/058392.html). I've opted for following Eli Friedman's advice to print warnings when there are reserved registers on the clobber list so as not to diverge from GCC behavior for now.

The patch uses MachineRegisterInfo's target-specific knowledge of reserved registers, just before we convert the inline asm string in the AsmPrinter.

If we find a reserved register, we print a warning:
```
repro.c:6:7: warning: inline asm clobber list contains reserved registers: R7 [-Winline-asm]
      "mov r7, #1"
      ^
```

Reviewers: eli.friedman, olista01, javed.absar, efriedma

Reviewed By: efriedma

Subscribers: efriedma, eraman, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D49727

llvm-svn: 339257
2018-08-08 15:15:59 +00:00
Simon Pilgrim 164e8b0b5c [TargetLowering] BuildUDIV - Add support for divide by one (PR38477)
Provide a pass-through of the numerator for divide by one cases - this is the same approach we take in DAGCombiner::visitSDIVLike.

I investigated whether we could achieve this by magic MULHU/SRL values but nothing appeared to work as we don't have a way for MULHU(x,c) -> x

llvm-svn: 339254
2018-08-08 14:51:19 +00:00
Simon Pilgrim e4a4cf5a8b [TargetLowering] Remove APInt divisor argument from BuildExactSDIV (NFCI).
As requested in D50392, this is a minor refactor to BuildExactSDIV to stop taking the uniform constant APInt divisor and instead extract it locally.

I also cleanup the operands and valuetypes to better match BuildUDiv (and BuildSDIV in the near future).

llvm-svn: 339246
2018-08-08 13:59:44 +00:00
Ties Stuij 81f1fbdf5a test commit access
Summary: changing a few typos

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D50445

llvm-svn: 339245
2018-08-08 13:51:13 +00:00
Simon Pilgrim a10cfcc1db [TargetLowering] BuildUDIV - Early out for divide by one (PR38477)
We're not handling the UDIV by one special case properly - for now just early out.

llvm-svn: 339229
2018-08-08 10:00:54 +00:00
Thomas Preud'homme 4107b31df2 Support inline asm with multiple 64bit output in 32bit GPR
Summary: Extend fix for PR34170 to support inline assembly with multiple output operands that do not naturally go in the register class it is constrained to (eg. double in a 32-bit GPR as in the PR).

Reviewers: bogner, t.p.northover, lattner, javed.absar, efriedma

Reviewed By: efriedma

Subscribers: efriedma, tra, eraman, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D45437

llvm-svn: 339225
2018-08-08 09:35:26 +00:00
Craig Topper 49ed49fcb1 [SelectionDAG] When splitting scatter nodes during DAGCombine, create a serial chain dependency.
Scatter could have multiple identical indices. We need to maintain sequential order. We get this right in LegalizeVectorTypes, but not in this code.

Differential Revision: https://reviews.llvm.org/D50374

llvm-svn: 339157
2018-08-07 17:35:02 +00:00
Simon Pilgrim 1bfadb0499 [DAG] Allow non-uniform constant vectors to call BuildSDIV
This was missed in D50185.

NFC until we add actual non-uniform support to BuildSDIV (similar BuildUDIV support in D49248) - for now it just early outs.

llvm-svn: 339147
2018-08-07 14:50:39 +00:00
Simon Pilgrim 6943e39353 [TargetLowering] Use pre-computed Shift value type in BuildUDIV (NFCI)
This was missed in D49248

llvm-svn: 339146
2018-08-07 14:40:21 +00:00
Jonas Devlieghere 42243df3b9 Fix inconsistency with/without debug information (-g)
This fixes an inconsistency in code generation when compiling with or
without debug information (-g). When debug information is available in
an empty block, the original test would fail, resulting in possibly
different code.

Patch by: Jeroen Dobbelaere

Differential revision: https://reviews.llvm.org/D49467

llvm-svn: 339129
2018-08-07 12:14:01 +00:00
Pavel Labath 2f0881160c [DebugInfo] Reduce debug_str_offsets section size
Summary:
The accelerator tables use the debug_str section to store their strings.
However, they do not support the indirect method of access that is
available for the debug_info section (DW_FORM_strx et al.).

Currently our code is assuming that all strings can/will be referenced
indirectly, and puts all of them into the debug_str_offsets section.
This is generally true for regular (unsplit) dwarf, but in the DWO case,
most of the strings in the debug_str section will only be used from the
accelerator tables. Therefore the contents of the debug_str_offsets
section will be largely unused and bloating the main executable.

This patch rectifies this by teaching the DwarfStringPool to
differentiate between strings accessed directly and indirectly. When a
user inserts a string into the pool it has to declare whether that
string will be referenced directly or not. If at least one user requsts
indirect access, that string will be assigned an index ID and put into
debug_str_offsets table. Otherwise, the offset table is skipped.

This approach reduces the overall binary size (when compiled with
-gdwarf-5 -gsplit-dwarf) in my tests by about 2% (debug_str_offsets is
shrunk by 99%).

Reviewers: probinson, dblaikie, JDevlieghere

Subscribers: aprantl, mgrang, llvm-commits

Differential Revision: https://reviews.llvm.org/D49493

llvm-svn: 339122
2018-08-07 09:54:52 +00:00
Simon Pilgrim 7e18938793 [TargetLowering] Add support for non-uniform vectors to BuildUDIV
This patch refactors the existing TargetLowering::BuildUDIV base implementation to support non-uniform constant vector denominators.

It also includes a fold for MULHU by pow2 constants to SRL which can now more readily occur from BuildUDIV.

Differential Revision: https://reviews.llvm.org/D49248

llvm-svn: 339121
2018-08-07 09:51:34 +00:00
Craig Topper 9de1797c50 [SelectionDAG][X86] Rename MaskedLoadSDNode::getSrc0 to getPassThru.
Src0 doesn't really convey any meaning to what the operand is. Passthru matches what's used in the documentation for the intrinsic this comes from.

llvm-svn: 339101
2018-08-07 06:52:49 +00:00
Craig Topper 17989208a9 [SelectionDAG][X86] Rename getValue to getPassThru for gather SDNodes.
getValue is more meaningful name for scatter than it is for gather. Split them and use getPassThru for gather.

llvm-svn: 339096
2018-08-07 06:13:40 +00:00
Reid Kleckner 5327805d7c Fix a -Wsign-compare
llvm-svn: 339059
2018-08-06 21:26:47 +00:00
Reid Kleckner 15e91c3235 [X86] Fix assertion in subreg extraction
This assert fires when attempting to extract a subregister from the
global PIC base register. This virtual register SD node is not in the
VRBaseMap, so we shouldn't call getVR to look it up there. If this is a
RegisterSDNode, we should be able to use the virtual register directly.

Fixes PR38385

llvm-svn: 339056
2018-08-06 21:16:16 +00:00
Wei Mi 3c1c088500 [RegisterCoalescer] Delay live interval update work until the rematerialization
for all the uses from the same def is done.

We run into a compile time problem with flex generated code combined with
`-fno-jump-tables`. The cause is that machineLICM hoists a lot of invariants
outside of a big loop, and drastically increases the compile time in global
register splitting and copy coalescing.  https://reviews.llvm.org/D49353
relieves the problem in global splitting. This patch is to handle the problem
in copy coalescing.

About the situation where the problem in copy coalescing happens. After
machineLICM, we have several defs outside of a big loop with hundreds or
thousands of uses inside the loop. Rematerialization in copy coalescing
happens for each use and everytime rematerialization is done, shrinkToUses
will be called to update the huge live interval. Because we have 'n' uses
for a def, and each live interval update will have at least 'n' complexity,
the total update work is n^2.

To fix the problem, we try to do the live interval update work in a collective
way. If a def has many copylike uses larger than a threshold, each time
rematerialization is done for one of those uses, we won't do the live interval
update in time but delay that work until rematerialization for all those uses
are completed, so we only have to do the live interval update work once.

Delaying the live interval update could potentially change the copy coalescing
result, so we hope to limit that change to those defs with many
(like above a hundred) copylike uses, and the cutoff can be adjusted by the
option -mllvm -late-remat-update-threshold=xxx.

Differential Revision: https://reviews.llvm.org/D49519

llvm-svn: 339035
2018-08-06 17:30:45 +00:00
Hsiangkai Wang ef72e481ea [DebugInfo] Refactor DbgInfoIntrinsic class hierarchy.
In the past, DbgInfoIntrinsic has a strong assumption that these
intrinsics all have variables and expressions attached to them.
However, it is too strong to derive the class for other debug entities.
Now, it has problems for debug labels.

In order to make DbgInfoIntrinsic as a base class for 'debug info', I
create a class for 'variable debug info', DbgVariableIntrinsic.

DbgDeclareInst, DbgAddrIntrinsic, and DbgValueInst will be derived from it.

Differential Revision: https://reviews.llvm.org/D50220

llvm-svn: 338984
2018-08-06 03:59:47 +00:00
Aditya Nandakumar e07b3b737b [GISel]: Add Opcodes for CTLZ/CTTZ/CTPOP
https://reviews.llvm.org/D48600

Added IRTranslator support to translate these known intrinsics into GISel opcodes.

llvm-svn: 338944
2018-08-04 01:22:12 +00:00
Craig Topper c4960582ec [SelectionDAG] Teach LegalizeVectorTypes to widen the mask input to a masked store.
The mask operand is visited before the data operand so we need to be able to widen it.

Fixes PR38436.

llvm-svn: 338915
2018-08-03 20:14:18 +00:00
Matt Arsenault c3dc8e65e2 DAG: Enhance isKnownNeverNaN
Add a parameter for testing specifically for
sNaNs - at least one instruction pattern on AMDGPU
needs to check specifically for this.

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

llvm-svn: 338910
2018-08-03 18:27:52 +00:00
Simon Pilgrim 94112ebc75 [TargetLowering] Generalise BuildSDIV function
First step towards a BuildSDIV equivalent to D49248 for non-uniform vector support - this just pushes the splat detection down into TargetLowering::BuildSDIV where its still used.

Differential Revision: https://reviews.llvm.org/D50185

llvm-svn: 338838
2018-08-03 10:00:54 +00:00
Eli Friedman 1ba5e9ac24 [GlobalMerge] Allow merging globals with explicit section markings.
At least on ELF, it's impossible to tell from the object file whether
two globals with the same section marking were merged: the merged global
uses "private" linkage to hide its symbol, and the aliases look like
regular symbols. I can't think of any other reason to disallow it.
(Of course, we can only merge globals in the same section.)

The weird alignment handling matches AsmPrinter; our alignment handling
for global variables should probably be refactored.

Differential Revision: https://reviews.llvm.org/D49822

llvm-svn: 338791
2018-08-02 23:54:16 +00:00
Matt Arsenault 1f3977a856 DAG: Fix vector widening fcanonicalize
llvm-svn: 338715
2018-08-02 13:43:53 +00:00
Alexander Ivchenko 49168f6778 [GlobalISel] Rewrite CallLowering::lowerReturn to accept multiple VRegs per Value
This is logical continuation of https://reviews.llvm.org/D46018 (r332449)

Differential Revision: https://reviews.llvm.org/D49660

llvm-svn: 338685
2018-08-02 08:33:31 +00:00
Lei Liu b9a7b7a84d Fix FCOPYSIGN expansion
In expansion of FCOPYSIGN, the shift node is missing when the two
operands of FCOPYSIGN are of the same size. We should always generate
shift node (if the required shift bit is not zero) to put the sign
bit into the right position, regardless of the size of underlying
types.

Differential Revision: https://reviews.llvm.org/D49973

llvm-svn: 338665
2018-08-02 01:54:12 +00:00
Lei Liu 8e422b8403 [AArch64] DWARF: do not generate AT_location for thread local
AArch64 ELF ABI does not define a static relocation type for TLS offset within
a module, which makes it impossible for compiler to generate a valid
DW_AT_location content for thread local variables. Currently LLVM generates an
invalid R_AARCH64_ABS64 relocation at the DW_AT_location field for a TLS
variable. That causes trouble for linker because thread local variable does
not have an absolute address at link time. AArch64 GCC solves the problem by
not generating DW_AT_location for thread local variables. We should do the
same in LLVM.

Differential Revision: https://reviews.llvm.org/D43860

llvm-svn: 338655
2018-08-01 23:46:49 +00:00
Alexey Bataev d4dd7215f6 [DEBUGINFO] Disable emission of the dwarf sections, but allow directives.
Summary:
Added an option that allows to emit only '.loc' and '.file' kind debug
directives, but disables emission of the DWARF sections. Required for
NVPTX target to support profiling. It requires '.loc' and '.file'
directives, but does not require any DWARF sections for the profiler.

Reviewers: probinson, echristo, dblaikie

Subscribers: aprantl, JDevlieghere, llvm-commits

Differential Revision: https://reviews.llvm.org/D46021

llvm-svn: 338616
2018-08-01 19:38:20 +00:00