Commit Graph

30139 Commits

Author SHA1 Message Date
Kazu Hirata 8857202489 [llvm] Use llvm::find (NFC) 2021-01-19 20:19:14 -08:00
Ian Levesque 68a1f09107 [xray] Honor xray-never function-instrument attribute
function-instrument=xray-never wasn't actually honored before. We were
getting lucky that it worked because CodeGenFunction would omit the
other xray attributes when a function was annotated with
xray_never_instrument. This patch adds proper support.

Differential Revision: https://reviews.llvm.org/D89441
2021-01-19 18:47:09 -05:00
Jeroen Dobbelaere 121cac01e8 [noalias.decl] Look through llvm.experimental.noalias.scope.decl
Just like llvm.assume, there are a lot of cases where we can just ignore llvm.experimental.noalias.scope.decl.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D93042
2021-01-19 20:09:42 +01:00
Jessica Paquette cbf5246359 Fix buildbot after cfc6073017
Windows buildbots were not happy with using find_if + instructionsWithoutDebug.

In cfc6073017, instructionsWithoutDebug is not technically necessary. So,
just iterate over the block directly.

http://lab.llvm.org:8011/#/builders/127/builds/4732/steps/7/logs/stdio
2021-01-19 10:38:04 -08:00
Jessica Paquette cfc6073017 [GlobalISel] Combine (a[0]) | (a[1] << k1) | ...| (a[m] << kn) into a wide load
This is a restricted version of the combine in `DAGCombiner::MatchLoadCombine`.
(See D27861)

This tries to recognize patterns like below (assuming a little-endian target):

```
s8* x = ...
s32 val = a[0] | (a[1] << 8) | (a[2] << 16) | (a[3] << 24)
->
s32 val = *((i32)a)

s8* x = ...
s32 val = a[3] | (a[2] << 8) | (a[1] << 16) | (a[0] << 24)
->
s32 val = BSWAP(*((s32)a))
```

(This patch also handles the big-endian target case as well, in which the first
example above has a BSWAP, and the second example above does not.)

To recognize the pattern, this searches from the last G_OR in the expression
tree.

E.g.

```
    Reg   Reg
     \    /
      OR_1   Reg
       \    /
        OR_2
          \     Reg
           .. /
          Root
```

Each non-OR register in the tree is put in a list. Each register in the list is
then checked to see if it's an appropriate load + shift logic.

If every register is a load + potentially a shift, the combine checks if those
loads + shifts, when OR'd together, are equivalent to a wide load (possibly with
a BSWAP.)

To simplify things, this patch

(1) Only handles G_ZEXTLOADs (which appear to be the common case)
(2) Only works in a single MachineBasicBlock
(3) Only handles G_SHL as the bit twiddling to stick the small load into a
    specific location

An IR example of this is here: https://godbolt.org/z/4sP9Pj (lifted from
test/CodeGen/AArch64/load-combine.ll)

At -Os on AArch64, this is a 0.5% code size improvement for CTMark/sqlite3,
and a 0.4% improvement for CTMark/7zip-benchmark.

Also fix a bug in `isPredecessor` which caused it to fail whenever `DefMI` was
the first instruction in the block.

Differential Revision: https://reviews.llvm.org/D94350
2021-01-19 10:24:27 -08:00
Luo, Yuanke c535a7fdad [X86] Fix tile spill merge issue.
This is a additional bug fix for c5be0e0cc0. The distance for
the spill instructions is wrong in previous patch.

Differential Revision: https://reviews.llvm.org/D94772
2021-01-19 10:51:42 +08:00
Chen Zheng a9b3303a88 Revert "[NFC] [TargetRegisterInfo] add one use check to lookThruCopyLike."
This reverts commit 3bdf4507b6.

Post commit comments need to be addressed first.
2021-01-18 21:33:31 -05:00
Craig Topper 79e798aca3 Recommit "[RISCV] Add a test of vector sadd.overflow to demonstrate intrinsics with multiple scalable vector results."
This recommits 2c51bef76c.

I've fixed the broken check line from when I renamed the test function.

Original commit message:
This builds on D94142 where scalable vectors are allowed in structs.

I did have to fix one scalable vector issue in the vector type
creation for these intrinsics where we used getVectorNumElements
instead of ElementCount.
2021-01-18 11:08:28 -08:00
Craig Topper 5d431c3d32 Revert "[RISCV] Add a test of vector sadd.overflow to demonstrate intrinsics with multiple scalable vector results."
This reverts commit 2c51bef76c.

I seem to have messed up the check lines in the test.
2021-01-18 11:00:20 -08:00
Craig Topper 2c51bef76c [RISCV] Add a test of vector sadd.overflow to demonstrate intrinsics with multiple scalable vector results.
This builds on D94142 where scalable vectors are allowed in structs.

I did have to fix one scalable vector issue in the vector type
creation for these intrinsics where we used getVectorNumElements
instead of ElementCount.

Differential Revision: https://reviews.llvm.org/D94149
2021-01-18 10:41:36 -08:00
Kazu Hirata 23b0ab2acb [llvm] Use the default value of drop_begin (NFC) 2021-01-18 10:16:36 -08:00
Denis Antrushin f7443905af [Statepoint] Handle `undef` operands in statepoint.
Currently when spilling statepoint register operands in FixupStatepoints
we do not pay attention that it might be `undef`. We just generate a
spill, which may lead to verifier error because we have a use without def.

To handle it, let FixupStateponts ignore `undef` register operands
completely and change them to some constant value when generating
stack map. Use same value as used by ISel for this purpose (0xFEFEFEFE).

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D94703
2021-01-18 15:20:54 +03:00
Tres Popp 3bd24574c7 Revert "[PowerPC] support register pressure reduction in machine combiner."
This reverts commit 26a396c4ef.

See https://reviews.llvm.org/D92071 for a description of the issue.
2021-01-18 12:01:57 +01:00
Simon Pilgrim 207f32948b [DAG] SimplifyDemandedBits - use KnownBits comparisons to remove ISD::UMIN/UMAX ops
Use the KnownBits icmp comparisons to determine when a ISD::UMIN/UMAX op is unnecessary should either op be known to be ULT/ULE or UGT/UGE than the other.

Differential Revision: https://reviews.llvm.org/D94532
2021-01-18 10:29:23 +00:00
Craig Topper cfec6cd50c [IR] Allow scalable vectors in structs to support intrinsics returning multiple values.
RISC-V would like to use a struct of scalable vectors to return multiple
values from intrinsics. This woud also be needed for target independent
intrinsics like llvm.sadd.overflow.

This patch removes the existing restriction for this. I've modified
StructType::isSized to consider a struct containing scalable vectors
as unsized so the verifier won't allow loads/stores/allocas of these
structs.

Reviewed By: sdesmalen

Differential Revision: https://reviews.llvm.org/D94142
2021-01-17 23:29:51 -08:00
Chen Zheng 26a396c4ef [PowerPC] support register pressure reduction in machine combiner.
Reassociating some patterns to generate more fma instructions to
reduce register pressure.

Reviewed By: jsji

Differential Revision: https://reviews.llvm.org/D92071
2021-01-17 23:56:13 -05:00
Qiu Chaofan f776d8b12f [Legalizer] Promote result type in expanding FP_TO_XINT
This patch promotes result integer type of FP_TO_XINT in expanding.
So crash in conversion from ppc_fp128 to i1 will be fixed.

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D92473
2021-01-18 11:56:11 +08:00
Chen Zheng 3bdf4507b6 [NFC] [TargetRegisterInfo] add one use check to lookThruCopyLike.
add one use check to lookThruCopyLike.

The root node is safe to be deleted if we are sure that every
definition in the copy chain only has one use.

Reviewed By: jsji

Differential Revision: https://reviews.llvm.org/D92069
2021-01-17 19:56:42 -05:00
Kazu Hirata 2082b10d10 [llvm] Use *::empty (NFC) 2021-01-16 09:40:55 -08:00
Kazu Hirata 19aacdb715 [llvm] Construct SmallVector with iterator ranges (NFC) 2021-01-16 09:40:53 -08:00
Bjorn Pettersson 4f15556731 [LegalizeDAG] Handle NeedInvert when expanding BR_CC
This is a follow-up fix to commit 03c8d6a0c4.
Seems like we now end up with NeedInvert being set in the result
from LegalizeSetCCCondCode more often than in the past, so we
need to handle NeedInvert when expanding BR_CC.

Not sure how to deal with the "Tmp4.getNode()" case properly,
but current assumption is that that code path isn't impacted
by the changes in 03c8d6a0c4 so we can simply move
the old assert into the if-branch and only handle NeedInvert in the
else-branch.

I think that the test case added here, for PowerPC, might have
failed also before commit 03c8d6a0c4. But we started
to hit the assert more often downstream when having merged that
commit.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D94762
2021-01-16 14:33:19 +01:00
Jeroen Dobbelaere 668827b648 Introduce llvm.noalias.decl intrinsic
The ``llvm.experimental.noalias.scope.decl`` intrinsic identifies where a noalias
scope is declared. When the intrinsic is duplicated, a decision must
also be made about the scope: depending on the reason of the duplication,
the scope might need to be duplicated as well.

Reviewed By: nikic, jdoerfert

Differential Revision: https://reviews.llvm.org/D93039
2021-01-16 09:20:45 +01:00
Kazu Hirata 8fd8ff1f67 [StringExtras] Rename SubsequentDelim to ListSeparator
This patch renames SubsequentDelim to ListSeparator to clarify the
purpose of the class.

Differential Revision: https://reviews.llvm.org/D94649
2021-01-15 21:00:56 -08:00
Craig Topper a9e939760c [CodeGen] Removes unwanted optimisation for TargetConstantFP
This 'FIXME' popped up in the development of an out-of-tree backend.
Quick fix, but first llvm upstream patch, therefore I do not have commit rights, so if approved please commit?

- Test is not included as this came up in an out-of-tree backend (if required, please hint on how to test this).

Patch by simveg (Simon)

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D93219
2021-01-15 11:52:53 -08:00
Craig Topper 4c5066b078 [TargetLowering] Don't speculatively call ComputeNumSignBits. NFC
These methods are recursive so a little costly.

We only look at the result in one place in this function and it's
conditional. We also only need the second call if the first had
enough returned enough sign bits.
2021-01-15 09:09:35 -08:00
Simon Pilgrim 46aa3c6c33 [DAG] visitVECTOR_SHUFFLE - MergeInnerShuffle - improve shuffle(shuffle(x,y),shuffle(x,y)) merging
MergeInnerShuffle currently attempts to merge shuffle(shuffle(x,y),z) patterns into a single shuffle, using 1 or 2 of the x,y,z ops.

However if we already match 2 ops we might be able to handle the third op if its also a shuffle that references one of the previous ops, allowing us to handle some cases like:

shuffle(shuffle(x,y),shuffle(x,y))
shuffle(shuffle(shuffle(x,z),y),z)
shuffle(shuffle(x,shuffle(x,y)),z)
etc.

This isn't an exhaustive match and is dependent on the order the candidate ops are encountered - if one of the matched ops was a shuffle that was peek-able we don't go back and try to split that, I haven't found much need for that amount of analysis yet.

This is a preliminary patch that will allow us to later improve x86 HADD/HSUB matching - but needs to be reviewed separately as its in generic code and affects existing Thumb2 tests.

Differential Revision: https://reviews.llvm.org/D94671
2021-01-15 15:08:31 +00:00
Kazu Hirata 7dc3575ef2 [llvm] Remove redundant return and continue statements (NFC)
Identified with readability-redundant-control-flow.
2021-01-14 20:30:34 -08:00
Kazu Hirata 2efcbe24a7 [llvm] Use llvm::drop_begin (NFC) 2021-01-14 20:30:33 -08:00
Kazu Hirata 9bcc0d1040 [CodeGen, Transforms] Use llvm::sort (NFC) 2021-01-14 20:30:31 -08:00
Jay Foad 868da2ea93 [SelectionDAG] Remove an early-out from computeKnownBits for smin/smax
Even if we know nothing about LHS, it can still be useful to know that
smax(LHS, RHS) >= RHS and smin(LHS, RHS) <= RHS.

Differential Revision: https://reviews.llvm.org/D87145
2021-01-14 18:15:17 +00:00
Jay Foad 517196e569 [Analysis,CodeGen] Make use of KnownBits::makeConstant. NFC.
Differential Revision: https://reviews.llvm.org/D94588
2021-01-14 14:02:43 +00:00
Jay Foad a1cba5b7a1 [SelectionDAG] Make use of KnownBits::commonBits. NFC.
Differential Revision: https://reviews.llvm.org/D94587
2021-01-14 14:02:43 +00:00
Simon Pilgrim 7c30c05ff7 [DAG] visitVECTOR_SHUFFLE - MergeInnerShuffle - reset shuffle ops and reorder early-out and second op matching. NFCI.
I'm hoping to reuse MergeInnerShuffle in some other folds - so ensure the candidate ops/mask are reset at the start of each run.

Also, move the second op matching before bailing to make it simpler to try to match other things afterward.
2021-01-14 11:55:20 +00:00
Simon Pilgrim af8d27a7a8 [DAG] visitVECTOR_SHUFFLE - pull out shuffle merging code into lambda helper. NFCI.
Make it easier to reuse in a future patch.
2021-01-14 11:05:19 +00:00
David Stuttard 259936f491 [NFC][AsmPrinter] Windows warning: Use explicit cast
static_cast for uint64_t to unsigned gives a MS VC build warning
for Windows:

warning C4309: 'static_cast': truncation of constant value

Use an explicit cast instead.

Change-Id: I692d335b4913070686a102780c1fb05b893a2f69

Differential Revision: https://reviews.llvm.org/D94592
2021-01-14 09:10:31 +00:00
Kazu Hirata 125ea20d55 [llvm] Use llvm::stable_sort (NFC) 2021-01-13 19:14:43 -08:00
Kazu Hirata 5c1c39e8d8 [llvm] Use *Set::contains (NFC) 2021-01-13 19:14:41 -08:00
Simon Pilgrim 993c488ed2 [DAG] visitVECTOR_SHUFFLE - use all_of to check for all-undef shuffle mask. NFCI. 2021-01-13 17:19:41 +00:00
Matt Arsenault d55d592a92 GlobalISel: Do not set observer of MachineIRBuilder in LegalizerHelper
This fixes double printing of insertion debug messages in the
legalizer.

Try to cleanup usage of observers. Currently the use of observers is
pretty hard to follow and it's not clear what is responsible for
them. Observers are referenced in 3 places:

1. In the MachineFunction
2. In the MachineIRBuilder
3. In the LegalizerHelper

The observers in the MachineFunction and MachineIRBuilder are both
called only on insertions, and are redundant with each other. The
source of the double printing was the same observer was added to both
the MachineFunction, and the MachineIRBuilder. One of these references
needs to be removed. Arguably observers in general should be fully
removed from one or the other, but it may be useful to have a local
observer in the MachineIRBuilder that is not added to the function's
observers. Alternatively, the wrapper observer could manage a local
observer in one place.

The LegalizerHelper only ever calls the observer on changing/changed
instructions, and never insertions. Logically these are two different
types of observers, for changes and for insertions.

Additionally, some places used the GISelObserverWrapper when they only
needed a single observer they could use directly.

Setting the observer in the LegalizerHelper constructor is not
flexible enough if the LegalizerHelper is constructed anywhere outside
the one used by the legalizer. AMDGPU calls the LegalizerHelper in
RegBankSelect, and needs to use a local observer to apply the regbank
to newly created instructions. Currently it accomplishes this by
constructing a local MachineIRBuilder. I'm trying to move the
MachineIRBuilder to be owned/maintained by the RegBankSelect pass
itself, but the locally constructed LegalizerHelper would reset the
observer.

Mips also has a special case use of the LegalizationArtifactCombiner
in applyMappingImpl; I think we do need to run the artifact combiner
during RegBankSelect, but in a more consistent way outside of
applyMappingImpl.
2021-01-13 10:44:31 -05:00
Kerry McLaughlin 2170e0ee60 [SVE][CodeGen] CTLZ, CTTZ & CTPOP operations (predicates)
Canonicalise the following operations in getNode() for predicate types:
 - CTLZ(Pred)  -> bitwise_NOT(Pred)
 - CTTZ(Pred)  -> bitwise_NOT(Pred)
 - CTPOP(Pred) -> Pred

Reviewed By: david-arm

Differential Revision: https://reviews.llvm.org/D94428
2021-01-13 12:24:54 +00:00
Serguei Katkov 8f8c207b8f [Verifier] Add tied-ness verification to statepoint intsruction
Reviewers: reames, dantrushin
Reviewed By: reames, dantrushin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D94483
2021-01-13 14:40:44 +07:00
Kazu Hirata 2c2d489b78 [CodeGen] Remove unused function isRegLiveInExitBlocks (NFC)
The last use was removed on Jan 17, 2020 in commit
42350cd893.
2021-01-12 21:43:48 -08:00
Kazu Hirata 12fc9ca3a4 [llvm] Remove redundant string initialization (NFC)
Identified with readability-redundant-string-init.
2021-01-12 21:43:46 -08:00
Serguei Katkov fba9805ba3 [Verifier] Extend statepoint verifier to cover more constants
Also old mir tests are updated to meet last changes in STATEPOINT format.

Reviewers: reames, dantrushin
Reviewed By: reames, dantrushin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D94482
2021-01-13 11:51:48 +07:00
Serguei Katkov 157efd84ab [Statepoint Lowering] Add an option to allow use gc values in regs for landing pad
Default value is not changed, so it is NFC actually.

The option allows to use gc values on registers in landing pads.

Reviewers: reames, dantrushin
Reviewed By: reames, dantrushin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D94469
2021-01-13 11:39:34 +07:00
Serguei Katkov f454c9f102 [InlineSpiller] Re-tie operands if folding failed
InlineSpiller::foldMemoryOperand unties registers before an attempt to fold and
does not restore tied-ness in case of failure.

I do not have a particular test for demo of invalid behavior.
This is something of clean-up.
It is better to keep the behavior correct in case some time in future it happens.

Reviewers: reames, dantrushin
Reviewed By: dantrushin, reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D94389
2021-01-13 10:31:43 +07:00
Juneyoung Lee 25eb7b08ba [DAGCombiner] Fold BRCOND(FREEZE(COND)) to BRCOND(COND)
This patch resolves the suboptimal codegen described in http://llvm.org/pr47873 .
When CodeGenPrepare lowers select into a conditional branch, a freeze instruction is inserted.
It is then translated to `BRCOND(FREEZE(SETCC))` in SelDag.
The `FREEZE` in the middle of `SETCC` and `BRCOND` was causing a suboptimal code generation however.
This patch adds `BRCOND(FREEZE(cond))` -> `BRCOND(cond)` fold to DAGCombiner to remove the `FREEZE`.

To make this optimization sound, `BRCOND(UNDEF)` simply should nondeterministically jump to the branch or not, rather than raising UB.
It wasn't clear what happens when the condition was undef according to the comments in ISDOpcodes.h, however.
I updated the comments of `BRCOND` to make it explicit (as well as `BR_CC`, which is also a conditional branch instruction).

Note that it diverges from the semantics of `br` instruction in IR, which is explicitly UB.
Since the UB semantics was necessary to explain optimizations that use branching conditions, and SelDag doesn't seem to have such optimization, I think this divergence is okay.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D92015
2021-01-13 09:36:52 +09:00
Craig Topper 03c8d6a0c4 [LegalizeDAG][RISCV][PowerPC][AMDGPU][WebAssembly] Improve expansion of SETONE/SETUEQ on targets without SETO/SETUO.
If SETO/SETUO aren't legal, they'll be expanded and we'll end up
with 3 comparisons.

SETONE is equivalent to (SETOGT || SETOLT)
so if one of those operations is supported use that expansion. We
don't need both since we can commute the operands to make the other.

SETUEQ can be implemented with !(SETOGT || SETOLT) or (SETULE && SETUGE).
I've only implemented the first because it didn't look like most of the
affected targets had legal SETULE/SETUGE.

Reviewed By: frasercrmck, tlively, nemanjai

Differential Revision: https://reviews.llvm.org/D94450
2021-01-12 10:45:03 -08:00
Jay Foad f264f9ad7d [SlotIndexes] Fix and simplify basic block splitting
Remove the InsertionPoint argument from SlotIndexes::insertMBBInMaps
because it was confusing: what does it mean to insert a new block
between two instructions, in the middle of an existing block?

Instead, support the case that MachineBasicBlock::splitAt really needs,
where the new block contains some instructions that are already in the
maps because they have been moved there from the tail of the previous
block.

In all other use cases the new block is empty.

Based on work by Carl Ritson!

Differential Revision: https://reviews.llvm.org/D94311
2021-01-12 10:50:14 +00:00
Sander de Smalen c8a914db5c [LiveDebugValues] Fix comparison operator in VarLocBasedImpl
The issue was introduced in commit rG84a1120943a651184bae507fed5d648fee381ae4
and would cause a VarLoc's StackOffset to be compared with its own, instead of
the StackOffset from the other VarLoc. This patch fixes that.
2021-01-12 08:44:58 +00:00
Craig Topper df74c001fa [DAGCombiner] Replace static helper function isConstantFPBuildVectorOrConstantFP with the identical version in SelectionDAG. NFC 2021-01-11 23:41:40 -08:00
Craig Topper f9ef3a6003 [SelectionDAG] Make isConstantIntBuildVectorOrConstantInt and isConstantFPBuildVectorOrConstantFP methods const. 2021-01-11 23:26:53 -08:00
Craig Topper b1c304c494 [CodeGen] Try to make the print of memory operand alignment a little more user friendly.
Memory operands store a base alignment that does not factor in
the effect of the offset on the alignment.

Previously the printing code only printed the base alignment if
it was different than the size. If there is an offset, the reader
would need to figure out the effective alignment themselves. This
has confused me before and someone else was recently confused on
IRC.

This patch prints the possibly offset adjusted alignment if it is
different than the size. And prints the base alignment if it is
different than the alignment. The MIR parser has been updated to
read basealign in addition to align.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D94344
2021-01-11 19:58:47 -08:00
David Stuttard 5464baaae8 Fix minor build issue (NFC)
Change [x86] Fix tile register spill issue was causing problems for our build
using gcc-5.4.1

The problem was caused by this line:

for (const MachineInstr &MI : make_range(MIS.begin(), MI))

where MI was previously defined as a MachineBasicBlock iterator.

Differential Revision: https://reviews.llvm.org/D94415
2021-01-11 11:24:09 -08:00
Paul Robinson 1f9c29228c [FastISel] NFC: Clean up unnecessary bookkeeping
Now that we flush the local value map for every instruction, we don't
need any extra flushes for specific cases.  Also, LastFlushPoint is
not used for anything.  Follow-ups to #c161665 (D91734).

This reapplies #3fd39d3.

Differential Revision: https://reviews.llvm.org/D92338
2021-01-11 09:40:39 -08:00
Paul Robinson be179b9946 [FastISel] NFC: Remove obsolete -fast-isel-sink-local-values option
This option is not used for anything after #c161665 (D91737).
This commit reapplies #a474657.
2021-01-11 09:32:49 -08:00
Paul Robinson c161775dec [FastISel] Flush local value map on every instruction
Local values are constants or addresses that can't be folded into
the instruction that uses them. FastISel materializes these in a
"local value" area that always dominates the current insertion
point, to try to avoid materializing these values more than once
(per block).

https://reviews.llvm.org/D43093 added code to sink these local
value instructions to their first use, which has two beneficial
effects. One, it is likely to avoid some unnecessary spills and
reloads; two, it allows us to attach the debug location of the
user to the local value instruction. The latter effect can
improve the debugging experience for debuggers with a "set next
statement" feature, such as the Visual Studio debugger and PS4
debugger, because instructions to set up constants for a given
statement will be associated with the appropriate source line.

There are also some constants (primarily addresses) that could be
produced by no-op casts or GEP instructions; the main difference
from "local value" instructions is that these are values from
separate IR instructions, and therefore could have multiple users
across multiple basic blocks. D43093 avoided sinking these, even
though they were emitted to the same "local value" area as the
other instructions. The patch comment for D43093 states:

  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.

This patch undoes most of D43093, and instead flushes the local
value map after(*) every IR instruction, using that instruction's
debug location. This avoids sometimes incorrect locations used
previously, and emits instructions in a more natural order.

In addition, constants materialized due to PHI instructions are
not assigned a debug location immediately; instead, when the
local value map is flushed, if the first local value instruction
has no debug location, it is given the same location as the
first non-local-value-map instruction.  This prevents PHIs
from introducing unattributed instructions, which would either
be implicitly attributed to the location for the preceding IR
instruction, or given line 0 if they are at the beginning of
a machine basic block.  Neither of those consequences is good
for debugging.

This does mean materialized values are not re-used across IR
instruction boundaries; however, only about 5% of those values
were reused in an experimental self-build of clang.

(*) Actually, just prior to the next instruction. It seems like
it would be cleaner the other way, but I was having trouble
getting that to work.

This reapplies commits cf1c774d and dc35368c, and adds the
modification to PHI handling, which should avoid problems
with debugging under gdb.

Differential Revision: https://reviews.llvm.org/D91734
2021-01-11 08:32:36 -08:00
Joe Ellis 007358239d [DAGCombiner] Use getVectorElementCount inside visitINSERT_SUBVECTOR
This avoids TypeSize-/ElementCount-related warnings.

Differential Revision: https://reviews.llvm.org/D92747
2021-01-11 14:15:11 +00:00
Luo, Yuanke c5be0e0cc0 [X86] Fix tile register spill issue.
The tile register spill need 2 instructions.
%46:gr64_nosp = MOV64ri 64
TILESTORED %stack.2, 1, killed %46:gr64_nosp, 0, $noreg, %43:tile
The first instruction load the stride to a GPR, and the second
instruction store tile register to stack slot. The optimization of merge
spill instruction is done after register allocation. And spill tile
register need create a new virtual register to for stride, so we can't
hoist tile spill instruction in postOptimization() of register
allocation. We can't hoist TILESTORED alone and we can't hoist the 2
instuctions together because MOV64ri will clobber some GPR. This patch
is to disble the spill merge for any spill which need 2 instructions.

Differential Revision: https://reviews.llvm.org/D93898
2021-01-11 18:35:09 +08:00
Hsiangkai Wang 5e476061de [NFC][AsmPrinter] Make comments for spill/reload more precise.
The size of spill/reload may be unknown for scalable vector types.
When the size is unknown, print it as "Unknown-size" instead of a very
large number.

Differential Revision: https://reviews.llvm.org/D94299
2021-01-11 15:00:27 +08:00
QingShan Zhang 7539c75bb4 [DAGCombine] Remove the check for unsafe-fp-math when we are checking the AFN
We are checking the unsafe-fp-math for sqrt but not for fpow, which behaves inconsistent.
As the direction is to remove this global option, we need to remove the unsafe-fp-math
check for sqrt and update the test with afn fast-math flags.

Reviewed By: Spatel

Differential Revision: https://reviews.llvm.org/D93891
2021-01-11 02:25:53 +00:00
Kazu Hirata 407b1e65a4 [StringExtras] Add a helper class for comma-separated lists
This patch introduces a helper class SubsequentDelim to simplify loops
that generate a comma-separated lists.

For example, consider the following loop, taken from
llvm/lib/CodeGen/MachineBasicBlock.cpp:

    for (auto I = pred_begin(), E = pred_end(); I != E; ++I) {
      if (I != pred_begin())
        OS << ", ";
      OS << printMBBReference(**I);
    }

The new class allows us to rewrite the loop as:

    SubsequentDelim SD;
    for (auto I = pred_begin(), E = pred_end(); I != E; ++I)
      OS << SD << printMBBReference(**I);

where SD evaluates to the empty string for the first time and ", " for
subsequent iterations.

Unlike interleaveComma, defined in llvm/include/llvm/ADT/STLExtras.h,
SubsequentDelim can accommodate a wider variety of loops, including:

- those that conditionally skip certain items,
- those that need iterators to call getSuccProbability(I), and
- those that iterate over integer ranges.

As an example, this patch cleans up MachineBasicBlock::print.

Differential Revision: https://reviews.llvm.org/D94377
2021-01-10 14:32:02 -08:00
Kazu Hirata e3d3dbd339 [llvm] Ensure newlines at the end of files (NFC)
This patch eliminates pesky "No newline at end of file" messages from
git diff.
2021-01-10 09:24:57 -08:00
Kazu Hirata 9850d3b10a [CodeGen, DebugInfo] Use llvm::find_if (NFC) 2021-01-10 09:24:53 -08:00
Juneyoung Lee 9f2d9364b0 [CodeGen] Update transformations to use poison for shufflevector/insertelem's initial vector elem
This patch is a part of D93817 and makes transformations in CodeGen use poison for shufflevector/insertelem's initial vector element.

The change in CodeGenPrepare.cpp is fine because the mask of shufflevector should be always zero.
It doesn't touch the second element (which is poison).

The change in InterleavedAccessPass.cpp is also fine becauses the mask is of the form <a, a+m, a+2m, .., a+km> where a+km is smaller than
the size of the first vector operand.
This is guaranteed by the caller of replaceBinOpShuffles, which is lowerInterleavedLoad.
It calls isDeInterleaveMask and isDeInterleaveMaskOfFactor to check the mask is the desirable form.
isDeInterleaveMask has the check that a+km is smaller than the vector size.
To check my understanding, I added an assertion & added a test to show that this optimization doesn't fire in such case.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D94056
2021-01-10 18:03:51 +09:00
Fraser Cormack 41d06095b0 [SelectionDAG] Teach isConstOrConstSplat about ISD::SPLAT_VECTOR
This improves llvm::isConstOrConstSplat by allowing it to analyze
ISD::SPLAT_VECTOR nodes, in order to allow more constant-folding of
operations using scalable vector types.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D94168
2021-01-09 20:54:34 +00:00
Kazu Hirata 6a6e382161 [llvm] Drop unnecessary make_range (NFC) 2021-01-09 09:25:00 -08:00
Fraser Cormack de373ef779 [SelectionDAG] Extend immAll(Ones|Zeros)V to handle ISD::SPLAT_VECTOR
The TableGen immAllOnesV and immAllZerosV helpers implicitly wrapped the
ISD::isBuildVectorAll(Ones|Zeros) helper functions. This was inhibiting
their use for targets such as RISC-V which use ISD::SPLAT_VECTOR. In
particular, RISC-V had to define its own 'vnot' fragment.

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

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

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D94223
2021-01-09 17:05:31 +00:00
Heejin Ahn 52e240a072 [WebAssembly] Remove exnref and br_on_exn
This removes `exnref` type and `br_on_exn` instruction. This is
effectively NFC because most uses of these were already removed in the
previous CLs.

Reviewed By: dschuff, tlively

Differential Revision: https://reviews.llvm.org/D94041
2021-01-09 02:02:54 -08:00
Heejin Ahn 9e4eadeb13 [WebAssembly] Update basic EH instructions for the new spec
This implements basic instructions for the new spec.

- Adds new versions of instructions: `catch`, `catch_all`, and `rethrow`
- Adds support for instruction selection for the new instructions
 - `catch` needs a custom routine for the same reason `throw` needs one,
   to encode `__cpp_exception` tag symbol.
- Updates `WebAssembly::isCatch` utility function to include `catch_all`
  and Change code that compares an instruction's opcode with `catch` to
  use that function.
- LateEHPrepare
  - Previously in LateEHPrepare we added `catch` instruction to both
    `catchpad`s (for user catches) and `cleanuppad`s (for destructors).
    In the new version `catch` is generated from `llvm.catch` intrinsic
    in instruction selection phase, so we only need to add `catch_all`
    to the beginning of cleanup pads.
  - `catch` is generated from instruction selection, but we need to
    hoist the `catch` instruction to the beginning of every EH pad,
    because `catch` can be in the middle of the EH pad or even in a
    split BB from it after various code transformations.
  - Removes `addExceptionExtraction` function, which was used to
    generate `br_on_exn` before.
- CFGStackfiy: Deletes `fixUnwindMismatches` function. Running this
  function on the new instruction causes crashes, and the new version
  will be added in a later CL, whose contents will be completely
  different. So deleting the whole function will make the diff easier to
  read.
- Reenables all disabled tests in exception.ll and eh-lsda.ll and a
  single basic test in cfg-stackify-eh.ll.
- Updates existing tests to use the new assembly format. And deletes
  `br_on_exn` instructions from the tests and FileCheck lines.

Reviewed By: dschuff, tlively

Differential Revision: https://reviews.llvm.org/D94040
2021-01-09 01:48:06 -08:00
Heejin Ahn 9724c3cff4 [WebAssembly] Update WasmEHPrepare for the new spec
Clang generates `wasm.get.exception` and `wasm.get.ehselector`
intrinsics, which respectively return a caught exception value (a
pointer to some C++ exception struct) and a selector (an integer value
that tells which C++ `catch` clause the current exception matches, or
does not match any).

WasmEHPrepare is a pass that does some IR-level preparation before
instruction selection. Previously one of things we did in this pass was
to convert `wasm.get.exception` intrinsic calls to
`wasm.extract.exception` intrinsics. Their semantics were the same
except `wasm.extract.exception` did not have a token argument. We
maintained these two separate intrinsics with the same semantics because
instruction selection couldn't handle token arguments. This
`wasm.extract.exception` intrinsic was later converted to
`extract_exception` instruction in instruction selection, which was a
pseudo instruction to implement `br_on_exn`. Because `br_on_exn` pushed
an extracted value onto the value stack after the `end` instruction of a
`block`, but LLVM does not have a way of modeling that kind of behavior,
so this pseudo instruction was used to pull an extracted value out of
thin air, like this:
```
block $l0
  ...
  br_on_exn $cpp_exception $l0
  ...
end
extract_exception ;; pushes values onto the stack
```

In the new spec, we don't need this pseudo instruction anymore because
`catch` itself returns a value and we don't have `br_on_exn` anymore. In
the spec `catch` returns multiple values (like `br_on_exn`), but here we
assume it only returns a single i32, which is sufficient to support C++.

So this renames `wasm.get.exception` intrinsic to `wasm.catch`. Because
this CL does not yet contain instruction selection for `wasm.catch`
intrinsic, all `RUN` lines in exception.ll, eh-lsda.ll, and
cfg-stackify-eh.ll, and a single `RUN` line in wasm-eh.cpp (which is an
end-to-end test from C++ source to assembly) fail. So this CL
temporarily disables those `RUN` lines, and for those test files without
any valid remaining `RUN` lines, adds a dummy `RUN` line to make them
pass. These tests will be reenabled in later CLs.

Reviewed By: dschuff, tlively

Differential Revision: https://reviews.llvm.org/D94039
2021-01-08 23:38:26 -08:00
Kazu Hirata b7c5e0b02c [Target, Transforms] Use *Set::contains (NFC) 2021-01-08 18:39:54 -08:00
Heejin Ahn 7be271537e [WebAssembly] Rename wasm_rethrow_in_catch intrinsic/builtin
`wasm_rethrow_in_catch` intrinsic and builtin are used in order to
rethrow an exception when the exception is caught but there is no
matching clause within the current `catch`. For example,
```
try {
  foo();
} catch (int n) {
  ...
}
```
If the caught exception does not correspond to C++ `int` type, it should
be rethrown. These intrinsic/builtin were renamed `rethrow_in_catch`
because at the time I thought there would be another intrinsic for C++'s
`throw` keyword, which rethrows an exception. It turned out that `throw`
keyword doesn't require wasm's `rethrow` instruction, so we rename
`rethrow_in_catch` to just `rethrow` here.

Reviewed By: dschuff, tlively

Differential Revision: https://reviews.llvm.org/D94038
2021-01-08 06:55:04 -08:00
Simon Moll 611d3c63f3 [VP] ISD helper functions [VE] isel for vp_add, vp_and
This implements vp_add, vp_and for the VE target by lowering them to the
VVP_* layer. We also add helper functions for VP SDNodes (isVPSDNode,
getVPMaskIdx, getVPExplicitVectorLengthIdx).

Reviewed By: kaz7

Differential Revision: https://reviews.llvm.org/D93766
2021-01-08 14:29:45 +01:00
Sjoerd Meijer 8af859d514 [MachineLoop] New helper isLoopInvariant()
This factors out code from MachineLICM that determines whether an instruction
is loop-invariant, which is a generally useful function. Thus this allows to
use that helper elsewhere too.

Differential Revision: https://reviews.llvm.org/D94082
2021-01-08 09:04:56 +00:00
Christudasan Devadasan ae25a397e9 AMDGPU/GlobalISel: Enable sret demotion 2021-01-08 10:56:35 +05:30
Kazu Hirata 8febb2e0f5 [CodeGen] Remove unused function isCallerPreservedOrConstPhysReg (NFC)
The last use of the function was removed on Oct 20, 2018 in commit
8d6ff4c0af.
2021-01-07 20:29:32 -08:00
Matt Arsenault 2cbbc6e87c GlobalISel: Fail legalization on narrowing extload below memory size 2021-01-07 17:40:34 -05:00
Matt Arsenault 1f9b6ef91f GlobalISel: Add combine for G_UREM by power of 2
Really I want this in the legalizer, but this is a start.
2021-01-07 16:36:35 -05:00
Wouter van Oortmerssen 5c38ae36c5 [WebAssembly] Fixed byval args missing DWARF DW_AT_LOCATION
A struct in C passed by value did not get debug information. Such values are currently
lowered to a Wasm local even in -O0 (not to an alloca like on other archs), which becomes
a Target Index operand (TI_LOCAL). The DWARF writing code was not emitting locations
in for TI's specifically if the location is a single range (not a list).

In addition, the ExplicitLocals pass which removes the ARGUMENT pseudo instructions did
not update the associated DBG_VALUEs, and couldn't even find these values since the code
assumed such instructions are adjacent, which is not the case here.

Also fixed asm printing of TIs needed by a test.

Differential Revision: https://reviews.llvm.org/D94140
2021-01-07 10:31:38 -08:00
Matt Arsenault c9122ddef5 CodeGen: Refactor regallocator command line and target selection
Make the sequence of passes to select and rewrite instructions to
physical registers be a target callback. This is to prepare to allow
targets to split register allocation into multiple phases.
2021-01-07 13:13:25 -05:00
Simon Pilgrim 350ab7aa1c [DAG] Simplify OR(X,SHL(Y,BW/2)) eq/ne 0/-1 'all/any-of' style patterns
Attempt to simplify all/any-of style patterns that concatenate 2 smaller integers together into an and(x,y)/or(x,y) + icmp 0/-1 instead.

This is mainly to help some bool predicate reduction patterns where we end up concatenating bool vectors that have been bitcasted to integers.

Differential Revision: https://reviews.llvm.org/D93599
2021-01-07 12:03:19 +00:00
Sanjoy Das a855c9403f [NFC] Don't copy MachineFrameInfo on each invocation of HasAlias
Also fix a typo in a comment.  This fixes a compile time issue in XLA
(https://www.tensorflow.org/xla).

Differential Revision: https://reviews.llvm.org/D94182
2021-01-06 18:59:20 -08:00
Kazu Hirata cfeecdf7b6 [llvm] Use llvm::all_of (NFC) 2021-01-06 18:27:36 -08:00
Simon Pilgrim 1307e3f6c4 [TargetLowering] Add icmp ne/eq (srl (ctlz x), log2(bw)) vector support. 2021-01-06 16:13:51 +00:00
Sander de Smalen aa280c99f7 [AArch64][SVE] Emit DWARF location expr for SVE (dbg.declare)
When using dbg.declare, the debug-info is generated from a list of
locals rather than through DBG_VALUE instructions in the MIR.
This patch is different from D90020 because it emits the DWARF
location expressions from that list of locals directly.

Reviewed By: jmorse

Differential Revision: https://reviews.llvm.org/D90044
2021-01-06 11:45:05 +00:00
Sander de Smalen 84a1120943 [LiveDebugValues] Handle spill locations with a fixed and scalable component.
This patch fixes the two LiveDebugValues implementations
(InstrRef/VarLoc)Based to handle cases where the StackOffset contains
both a fixed and scalable component.

This depends on the `TargetRegisterInfo::prependOffsetExpression` being
added in D90020. Feel free to leave comments on that patch if you have them.

Reviewed By: djtodoro, jmorse

Differential Revision: https://reviews.llvm.org/D90046
2021-01-06 11:30:13 +00:00
Sander de Smalen a7e3339f3b [AArch64][SVE] Emit DWARF location expression for SVE stack objects.
Extend PEI to emit a DWARF expression for StackOffsets that have
a fixed and scalable component. This means the expression that needs
to be added is either:
  <base> + offset
or:
  <base> + offset + scalable_offset * scalereg

where for SVE, the scale reg is the Vector Granule Dwarf register, which
encodes the number of 64bit 'granules' in an SVE vector and which
the debugger can evaluate at runtime.

Reviewed By: jmorse

Differential Revision: https://reviews.llvm.org/D90020
2021-01-06 09:40:53 +00:00
Kazu Hirata cea1c63756 [MachineSink] Construct SmallVector with iterator ranges (NFC) 2021-01-05 21:15:57 -08:00
Christudasan Devadasan d68458bd56 [GlobalISel] Base implementation for sret demotion.
If the return values can't be lowered to registers
SelectionDAG performs the sret demotion. This patch
contains the basic implementation for the same in
the GlobalISel pipeline.

Furthermore, targets should bring relevant changes
during lowerFormalArguments, lowerReturn and
lowerCall to make use of this feature.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D92953
2021-01-06 10:30:50 +05:30
David Blaikie ad18b075fd DebugInfo: Add support for always using ranges (rather than low/high pc) in DWARFv5
Given the ability provided by DWARFv5 rnglists to reuse addresses in the
address pool, it can be advantageous to object file size to use range
encodings even when the range could be described by a direct low/high
pc.

Add a flag to allow enabling this in DWARFv5 for the purpose of
experimentation/data gathering.

It might be that it makes sense to enable this functionality by default
for DWARFv5 + Split DWARF at least, where the tradeoff/desire to
optimize for .o file size is more explicit and .o bytes are higher
priority than .dwo bytes.
2021-01-05 16:36:22 -08:00
Craig Topper 4ef91f5871 [DAGCombiner] Don't speculatively create an all ones constant in visitREM that might not be used.
This looks to have been done to save some duplicated code under
two different if statements, but it ends up being harmful to D94073.
This speculative constant can be called on a scalable vector type
with i64 element size when i64 scalars aren't legal. The code tries
and fails to find a vector type with i32 elements that it can use.

So only create the node when we know it will be used.
2021-01-05 12:45:57 -08:00
Matt Arsenault a427f15d60 GlobalISel: Add isKnownToBeAPowerOfTwo helper function 2021-01-05 12:59:08 -05:00
Jinsong Ji f26bc0ddd5 [RegisterClassInfo] Return non-zero for RC without allocatable reg
In some case, the RC may have 0 allocatable reg.
eg: VRSAVERC in PowerPC, which has only 1 reg, but it is also reserved.

The curreent implementation will keep calling the computePSetLimit because
getRegPressureSetLimit assume computePSetLimit will return a non-zero value.

The fix simply early return the value from TableGen for such special case.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D92907
2021-01-05 16:18:34 +00:00
Fraser Cormack 9a1ac97d3a [CodeGen] Format SelectionDAG::getConstant methods (NFC) 2021-01-05 12:59:46 +00:00
QingShan Zhang 2962f1149c [NFC] Add the getSizeInBytes() interface for MachineConstantPoolValue
Current implementation assumes that, each MachineConstantPoolValue takes
up sizeof(MachineConstantPoolValue::Ty) bytes. For PowerPC, we want to
lump all the constants with the same type as one MachineConstantPoolValue
to save the cost that calculate the TOC entry for each const. So, we need
to extend the MachineConstantPoolValue that break this assumption.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D89108
2021-01-05 03:22:45 +00:00
Roman Lebedev b4f519bddd
[NFCI] DwarfEHPrepare: update DomTree in non-permissive mode, when present
Being stricter will catch issues that would be just papered over
in permissive mode, and is likely faster.
2021-01-05 01:26:36 +03:00
Cameron McInally 92be640bd7 [FPEnv][AMDGPU] Disable FSUB(-0,X)->FNEG(X) DAGCombine when subnormals are flushed
This patch disables the FSUB(-0,X)->FNEG(X) DAG combine when we're flushing subnormals. It requires updating the existing AMDGPU tests to use the fneg IR instruction, in place of the old fsub(-0,X) canonical form, since AMDGPU is the only backend currently checking the DenormalMode flags.

Note that this will require follow-up optimizations to make sure the FSUB(-0,X) form is handled appropriately

Differential Revision: https://reviews.llvm.org/D93243
2021-01-04 14:44:10 -06:00
Kazu Hirata eb198f4c3c [llvm] Use llvm::any_of (NFC) 2021-01-04 11:42:47 -08:00
Florian Hahn ed936aad78
[InterleavedAccess] Return correct 'modified' status.
Both tryReplaceExtracts and replaceBinOpShuffles may modify the IR, even
if no interleaved loads are generated, but currently the pass pretends
no changes were made.

This patch updates the pass to return true if either of the functions
made any changes. In case of tryReplaceExtracts, changes are made if
there are any Extracts and true is returned.

`replaceBinOpShuffles` always makes changes if BinOpShuffles is not empty.
It also always returned true, so I went ahead and change it to just
`replaceBinOpShuffles`.

Fixes PR48208.

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D93997
2021-01-04 15:49:47 +00:00
Kazu Hirata ba82c0b315 [llvm] Call *(Set|Map)::erase directly (NFC)
We can erase an item in a set or map without checking its membership
first.
2021-01-03 09:57:47 -08:00
Brandon Bergren 8f004471c2 [PowerPC] Add the LLVM triple for powerpcle [1/5]
Add a triple for powerpcle-*-*.

This is a little-endian encoding of the 32-bit PowerPC ABI, useful in certain niche situations:

1) A loader such as the FreeBSD loader which will be loading a little endian kernel. This is required for PowerPC64LE to load properly in pseries VMs.
Such a loader is implemented as a freestanding ELF32 LSB binary.

2) Userspace emulation of a 32-bit LE architecture such as x86 on 64-bit hosts such as PowerPC64LE with tools like box86 requires having a 32-bit LE toolchain and library set, as they operate by translating only the main binary and switching to native code when making library calls.

3) The Void Linux for PowerPC project is experimenting with running an entire powerpcle userland.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D93918
2021-01-02 12:17:22 -06:00
Kazu Hirata 171c5fd43e [llvm] Use llvm::erase_value and llvm::erase_if (NFC) 2021-01-02 09:24:15 -08:00
Roman Lebedev f4ea21947d
[NFCI][CodeGen] DwarfEHPrepare: don't actually pass DTU into simplifyCFG by default
also, don't verify DomTree unless we intend to maintain it.
This is a very dumb think-o, i guess i was even warned about it
by subconsciousness in 4b80647367950ba3da6a08260487fd0dbc50a9c5's
commit message..

Fixes a compile-time regression reported by Martin Storsjö
in post-commit review of 2461cdb417.
2021-01-02 14:38:52 +03:00
Yang Fan 471dec3801
[CodeGen][NFC] Fix a build warning due to an extra semicolon 2021-01-02 10:42:58 +08:00
Roman Lebedev 2461cdb417
[CodeGen][SimplifyCFG] Teach DwarfEHPrepare to preserve DomTree
Once the default for SimplifyCFG flips, we can no longer pass nullptr
instead of DomTree to SimplifyCFG, so we need to propagate it here.

We don't strictly need to actually preserve DomTree in DwarfEHPrepare,
but we might as well do it, since it's trivial.
2021-01-02 01:01:19 +03:00
Roman Lebedev e6b1a27fb9
[NFC][CodeGen] Split DwarfEHPrepare pass into an actual transform and an legacy-PM wrapper
This is consistent with the layout of other passes,
and simplifies further refinements regarding DomTree handling.

This is indended to be a NFC commit.
2021-01-02 01:01:19 +03:00
Roman Lebedev c38739ad8f
[NFC] clang-format the entire DwarfEHPrepare.cpp 2021-01-02 01:01:19 +03:00
Sanjay Patel c74e8539ff [Analysis] flatten enums for recurrence types
This is almost all mechanical search-and-replace and
no-functional-change-intended (NFC). Having a single
enum makes it easier to match/reason about the
reduction cases.

The goal is to remove `Opcode` from reduction matching
code in the vectorizers because that makes it harder to
adapt the code to handle intrinsics.

The code in RecurrenceDescriptor::AddReductionVar() is
the only place that required closer inspection. It uses
a RecurrenceDescriptor and a second InstDesc to sometimes
overwrite part of the struct. It seem like we should be
able to simplify that logic, but it's not clear exactly
which cmp+sel patterns that we are trying to handle/avoid.
2021-01-01 12:20:16 -05:00
Fangrui Song d1fd72343c Refactor how -fno-semantic-interposition sets dso_local on default visibility external linkage definitions
The idea is that the CC1 default for ELF should set dso_local on default
visibility external linkage definitions in the default -mrelocation-model pic
mode (-fpic/-fPIC) to match COFF/Mach-O and make output IR similar.

The refactoring is made available by 2820a2ca3a.

Currently only x86 supports local aliases. We move the decision to the driver.
There are three CC1 states:

* -fsemantic-interposition: make some linkages interposable and make default visibility external linkage definitions dso_preemptable.
* (default): selected if the target supports .Lfoo$local: make default visibility external linkage definitions dso_local
* -fhalf-no-semantic-interposition: if neither option is set or the target does not support .Lfoo$local: like -fno-semantic-interposition but local aliases are not used. So references can be interposed if not optimized out.

Add -fhalf-no-semantic-interposition to a few tests using the half-based semantic interposition behavior.
2020-12-31 13:59:45 -08:00
Juneyoung Lee 5cdf6ed744 [CodeGen] recognize select form of and/ors when splitting branch conditions
Recently a few patches are made to move towards using select i1 instead of and/or i1 to represent "a && b"/"a || b" in C/C++.
"a && b" in C/C++ does not evaluate b if a is false whereas 'and a, b' in IR evaluates b and uses its result regardless of the result of a.
This is problematic because it can cause miscompilation if b was an erroneous operation (https://llvm.org/pr48353).
In C/C++, the result is simply false because b is not evaluated, but in IR the result is poison.
The discussion at D93065 has more context about this.

This patch makes two branch-splitting optimizations (one in SelectionDAGBuilder, one in CodeGenPrepare) recognize
select form of and/or as well using m_LogicalAnd/Or.
Since it is CodeGen, I think this is semantically ok (at least as safe as what codegen already did).

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D93853
2021-01-01 04:46:10 +09:00
Kazu Hirata 7bc76fd0ec [CodeGen] Construct SmallVector with iterator ranges (NFC) 2020-12-31 09:39:11 -08:00
Fangrui Song f731839584 [LowerEmuTls] Copy dso_local from <var> to __emutls_v.<var>
This effect is not testable until we drop the implied dso_local for ELF
static/PIE defined symbols from TargetMachine::shouldAssumeDSOLocal.
2020-12-30 16:11:32 -08:00
Juneyoung Lee 9b29610228 Use unary CreateShuffleVector if possible
As mentioned in D93793, there are quite a few places where unary `IRBuilder::CreateShuffleVector(X, Mask)` can be used
instead of `IRBuilder::CreateShuffleVector(X, Undef, Mask)`.
Let's update them.

Actually, it would have been more natural if the patches were made in this order:
(1) let them use unary CreateShuffleVector first
(2) update IRBuilder::CreateShuffleVector to use poison as a placeholder value (D93793)

The order is swapped, but in terms of correctness it is still fine.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D93923
2020-12-30 22:36:08 +09:00
Luo, Yuanke 981a0bd858 [X86] Add x86_amx type for intel AMX.
The x86_amx is used for AMX intrisics. <256 x i32> is bitcast to x86_amx when
it is used by AMX intrinsics, and x86_amx is bitcast to <256 x i32> when it
is used by load/store instruction. So amx intrinsics only operate on type x86_amx.
It can help to separate amx intrinsics from llvm IR instructions (+-*/).
Thank Craig for the idea. This patch depend on https://reviews.llvm.org/D87981.

Differential Revision: https://reviews.llvm.org/D91927
2020-12-30 13:52:13 +08:00
Yuanfang Chen 480936e741 Reland "[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline" (again)
This reverts commit 16c8f6e913 with fix.

-Wswitch catched an unhandled enum value due to recent commits in
TargetPassConfig.cpp.
2020-12-29 16:39:55 -08:00
Yuanfang Chen 16c8f6e913 Revert "Reland "[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline""
This reverts commit 21314940c4.

Build failure in some bots.
2020-12-29 16:29:07 -08:00
Yuanfang Chen 21314940c4 Reland "[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline"
This reverts commit 94427af60c (relands
4646de5d75 with fix).

Use "return std::move(AsmStreamer);" instead of "return AsmStreamer;" in
LVMTargetMachine::createMCStreamer. Unlike Clang, GCC seems having trouble
inserting a implicit lvalue->rvalue conversion.
2020-12-29 15:17:23 -08:00
Kazu Hirata 1e3ed09165 [CodeGen] Use llvm::append_range (NFC) 2020-12-28 19:55:16 -08:00
Yuanfang Chen 94427af60c Revert "[NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline"
This reverts commit 4646de5d75.

Some bots have build failure.
2020-12-28 17:44:22 -08:00
Yuanfang Chen 4646de5d75 [NewPM][CodeGen] Introduce CodeGenPassBuilder to help build codegen pipeline
Following up on D67687.
Please refer to the RFC here http://lists.llvm.org/pipermail/llvm-dev/2020-July/143309.html

`CodeGenPassBuilder` is the NPM counterpart of `TargetPassConfig` with below differences.
- Debugging features (MIR print/verify, disable pass, start/stop-before/after, etc.) living in `TargetPassConfig` are moved to use PassInstrument as much as possible. (Implementation also lives in `TargetPassConfig.cpp`)
- `TargetPassConfig` is a polymorphic base (virtual inheritance) to build the target-dependent pipeline whereas `CodeGenPassBuilder` is the CRTP base/helper to implement the target-dependent pipeline. The motivation is flexibility for targets to customize the pipeline, inlining opportunity, and fits the overall NPM value semantics design.
- `TargetPassConfig` is a legacy immutable pass to declare hooks for targets to customize some target-independent codegen layer behavior. This is partially ported to TargetMachine::options. The rest, such as `createMachineScheduler/createPostMachineScheduler`, are left out for now. They should be implemented in LLVMTargetMachine in the future.

Reviewed By: arsenm, aeubanks

Differential Revision: https://reviews.llvm.org/D83608
2020-12-28 17:36:36 -08:00
Gabriel Hjort Åkerlund b9a7c89d43 [MIRPrinter] Fix incorrect output of unnamed stack names
The MIRParser expects unnamed stack entries to have empty names ('').
In case of unnamed alloca instructions, the MIRPrinter would output
'<unnamed alloca>', which caused the MIRParser to reject the generated
code.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D93685
2020-12-28 18:01:40 +01:00
Chen Zheng 31c2b93d83 [MachineSink] add threshold in machinesink pass to reduce compiling time. 2020-12-27 23:23:07 -05:00
Kazu Hirata 789d250613 [CodeGen, Transforms] Use *Map::lookup (NFC) 2020-12-27 09:57:27 -08:00
Amara Emerson 7df3544e80 [GlobalISel] Fix assertion failures after "GlobalISel: Return APInt from getConstantVRegVal" landed.
APInt binary ops don't promote types but instead assert, which a combine was
relying on.
2020-12-26 23:51:44 -08:00
Kazu Hirata e457896a6e [CodeGen] Remove unused function hasInlineAsmMemConstraint (NFC)
The last use of the function was removed on Sep 13, 2010 in commit
1094c80281.
2020-12-24 09:17:58 -08:00
Kazu Hirata df812115e3 [CodeGen, Transforms] Use llvm::any_of (NFC) 2020-12-24 09:08:36 -08:00
Evgeniy Brevnov e0751234ef [CodeGen] Add "noreturn" attirbute to _Unwind_Resume
Currently 'resume' is lowered to _Unwind_Resume with out "noreturn" attribute. Semantically _Unwind_Resume  library call is expected to never return and should be marked as such. Though I didn't find any changes in behavior of existing tests there will be a difference once https://reviews.llvm.org/D79485 lands.

I was not able to come up with the test case anything better than just checking for presence of "noreturn" attribute. Please let me know if there is a better way to test the change.

Reviewed By: xbolva00

Differential Revision: https://reviews.llvm.org/D93682
2020-12-24 18:14:18 +07:00
Layton Kifer d29f93bda5 [DAGCombiner] Don't create sexts of deleted xors when they were in-visit replaced
Fixes a bug introduced by D91589.

When folding `(sext (not i1 x)) -> (add (zext i1 x), -1)`, we try to replace the not first when possible. If we replace the not in-visit, then the now invalidated node will be returned, and subsequently we will return an invalid sext. In cases where the not is replaced in-visit we can simply return SDValue, as the not in the current sext should have already been replaced.

Thanks @jgorbe, for finding the below reproducer.

The following reduced test case crashes clang when built with `clang -O1 -frounding-math`:

```
template <class> class a {
  int b() { return c == 0.0 ? 0 : -1; }
  int c;
};
template class a<long>;
```

A debug build of clang produces this "assertion failed" error:
```
clang: /home/jgorbe/code/llvm/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:264: void {anonymous}::DAGCombiner::AddToWorklist(llvm::
SDNode*): Assertion `N->getOpcode() != ISD::DELETED_NODE && "Deleted Node added to Worklist"' failed.
```

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D93274
2020-12-23 16:16:26 -08:00
Sriraman Tallam 34e70d722d Append ".__part." to every basic block section symbol.
Every basic block section symbol created by -fbasic-block-sections will contain
".__part." to know that this symbol corresponds to a basic block fragment of
the function.

This patch solves two problems:

a) Like D89617, we want function symbols with suffixes to be properly qualified
   so that external tools like profile aggregators know exactly what this
   symbol corresponds to.
b) The current basic block naming just adds a ".N" to the symbol name where N is
   some integer. This collides with how clang creates __cxx_global_var_init.N.
   clang creates these symbol names to call constructor functions and basic
   block symbol naming should not use the same style.

Fixed all the test cases and added an extra test for __cxx_global_var_init
breakage.

Differential Revision: https://reviews.llvm.org/D93082
2020-12-23 11:35:44 -08:00
Matt Arsenault 581d13f8ae GlobalISel: Return APInt from getConstantVRegVal
Returning int64_t was arbitrarily limiting for wide integer types, and
the functions should handle the full generality of the IR.

Also changes the full form which returns the originally defined
vreg. Add another wrapper for the common case of just immediately
converting to int64_t (arguably this would be useful for the full
return value case as well).

One possible issue with this change is some of the existing uses did
break without conversion to getConstantVRegSExtVal, and it's possible
some without adequate test coverage are now broken.
2020-12-22 22:23:58 -05:00
Matt Arsenault 5bec082834 VirtRegMap: Use Register 2020-12-22 20:56:14 -05:00
Arthur O'Dwyer 22cf54a7fb Replace `T(x)` with `reinterpret_cast<T>(x)` everywhere it means reinterpret_cast. NFC.
Differential Revision: https://reviews.llvm.org/D76572
2020-12-22 19:54:29 -05:00
Sjoerd Meijer 9a6de74d5a [MachineLICM] Add llvm debug messages to SinkIntoLoop. NFC.
I am investigating sinking instructions back into the loop under high
register pressure. This is just a first NFC step to add some debug
messages that allows tracing of the decision making.
2020-12-22 09:19:43 +00:00
Pavel Labath 8d75d902a9 [DebugInfo] Don't use DW_OP_implicit_value for fragments
Currently using DW_OP_implicit_value in fragments produces invalid DWARF
expressions. (Such a case can occur in complex floats, for example.)

This problem manifests itself as a missing DW_OP_piece operation after
the last fragment. This happens because the function for printing
constant float value skips printing the accompanying DWARF expression,
as that would also print DW_OP_stack_value (which is not desirable in
this case). However, this also results in DW_OP_piece being skipped.

The reason that DW_OP_piece is missing only for the last piece is that
the act of printing the next fragment corrects this. However, it does
that for the wrong reason -- the code emitting this DW_OP_piece thinks
that the previous fragment was missing, and so it thinks that it needs
to skip over it in order to be able to print itself.

In a simple scenario this works out, but it's likely that in a more
complex setup (where some pieces are in fact missing), this logic would
go badly wrong. In a simple setup gdb also seems to not mind the fact
that the DW_OP_piece is missing, but it would also likely not handle
more complex use cases.

For this reason, this patch disables the usage of DW_OP_implicit_value
in the frament scenario (we will use DW_OP_const*** instead), until we
figure out the right way to deal with this. This guarantees that we
produce valid expressions, and gdb can handle both kinds of inputs
anyway.

Differential Revision: https://reviews.llvm.org/D92013
2020-12-22 10:07:47 +01:00
Bing1 Yu e8ade4569b [LegalizeType] When LegalizeType procedure widens a masked_gather, set MemoryType's EltNum equal to Result's EltNum
When LegalizeType procedure widens a masked_gather, set MemoryType's EltNum equal to Result's EltNum.

As I mentioned in https://reviews.llvm.org/D91092, in previous code, If we have a v17i32's masked_gather in avx512, we widen it to a v32i32's masked_gather with a v17i32's MemoryType. When the SplitVecRes_MGATHER process this v32i32's masked_gather, GetSplitDestVTs will assert fail since what you are going to split is v17i32.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D93610
2020-12-22 13:27:38 +08:00
Fangrui Song d9a0c40bce [MC] Split MCContext::createTempSymbol, default AlwaysAddSuffix to true, and add comments
CanBeUnnamed is rarely false. Splitting to a createNamedTempSymbol makes the
intention clearer and matches the direction of reverted r240130 (to drop the
unneeded parameters).

No behavior change.
2020-12-21 14:04:13 -08:00
Denis Antrushin 6f45049fb6 [Statepoints] Disable VReg lowering for values used on exception path of invoke.
Currently we lower invokes the same way as usual calls, e.g.:

V1 = STATEPOINT ... V (tied-def 0)

But this is incorrect is V1 is used on exceptional path.
By LLVM rules V1 neither dominates its uses in landing pad, nor
its live range is live on entry to landing pad. So compiler is
allowed to do various weird transformations like splitting live
range after statepoint and use split LR in catch block.

Until (and if) we find better solution to this problem, let's
use old lowering (spilling) for those values which are used on
exceptional path and allow VReg lowering for values used only
on normal path.

Differential Revision: https://reviews.llvm.org/D93449
2020-12-21 20:27:05 +07:00
Fangrui Song 1635dea266 [AsmPrinter] Replace a reachable report_fatal_error with MCContext::reportError 2020-12-20 23:45:49 -08:00
Pushpinder Singh e2303a448e [FastRA] Fix handling of bundled MIs
Fast register allocator skips bundled MIs, as the main assignment
loop uses MachineBasicBlock::iterator (= MachineInstrBundleIterator)
This was causing SIInsertWaitcnts to crash which expects all
instructions to have registers assigned.

This patch makes sure to set everything inside bundle to the same
assignments done on BUNDLE header.

Reviewed By: qcolombet

Differential Revision: https://reviews.llvm.org/D90369
2020-12-21 02:10:55 -05:00
Chen Zheng 4dce7c2e20 [MachineLICM] delete dead flag if the duplicated def outside of loop is dead.
Fixup dead flags for CSE-ed instructions.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D92557
2020-12-20 19:26:22 -05:00
Kazu Hirata 3285ee143b [Analysis, IR, CodeGen] Use llvm::erase_if (NFC) 2020-12-20 09:19:35 -08:00
Kazu Hirata 805d59593f [Analysis, CodeGen, IR] Use contains (NFC) 2020-12-18 19:08:17 -08:00
Chih-Ping Chen 5f75dcf571 [DebugInfo] Support Fortran 'use <external module>' statement.
The main change is to add a 'IsDecl' field to DIModule so
that when IsDecl is set to true, the debug info entry generated
for the module would be marked as a declaration. That way, the debugger
would look up the definition of the module in the gloabl scope.

Please see the comments in llvm/test/DebugInfo/X86/dimodule.ll
for what the debug info entries would look like.

Differential Revision: https://reviews.llvm.org/D93462
2020-12-18 13:10:57 -05:00
Craig Blackmore 698ae90f30 [RegisterScavenging] Fix assert in scavengeRegisterBackwards
According to the documentation, if a spill is required to make a
register available and AllowSpill is false, then NoRegister should be
returned, however, this scenario was actually triggering an assertion
failure.

This patch moves the assertion after the handling of AllowSpill.

Authored by: Lewis Revill

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D92104
2020-12-18 16:57:05 +00:00
Matt Arsenault fd0f5fb8de PEI: Only call updateLiveness once per function
This only needs to be called once for the function, and it visits all
the necessary blocks in the function. It looks like
631f6b888c accidentally moved this into
the loop over all save blocks.
2020-12-18 11:02:28 -05:00
Bjorn Pettersson a89d751fb4 Add intrinsics for saturating float to int casts
This patch adds support for the fptoui.sat and fptosi.sat intrinsics,
which provide basically the same functionality as the existing fptoui
and fptosi instructions, but will saturate (or return 0 for NaN) on
values unrepresentable in the target type, instead of returning
poison. Related mailing list discussion can be found at:
https://groups.google.com/d/msg/llvm-dev/cgDFaBmCnDQ/CZAIMj4IBAAJ

The intrinsics have overloaded source and result type and support
vector operands:

    i32 @llvm.fptoui.sat.i32.f32(float %f)
    i100 @llvm.fptoui.sat.i100.f64(double %f)
    <4 x i32> @llvm.fptoui.sat.v4i32.v4f16(half %f)
    // etc

On the SelectionDAG layer two new ISD opcodes are added,
FP_TO_UINT_SAT and FP_TO_SINT_SAT. These opcodes have two operands
and one result. The second operand is an integer constant specifying
the scalar saturation width. The idea here is that initially the
second operand and the scalar width of the result type are the same,
but they may change during type legalization. For example:

    i19 @llvm.fptsi.sat.i19.f32(float %f)
    // builds
    i19 fp_to_sint_sat f, 19
    // type legalizes (through integer result promotion)
    i32 fp_to_sint_sat f, 19

I went for this approach, because saturated conversion does not
compose well. There is no good way of "adjusting" a saturating
conversion to i32 into one to i19 short of saturating twice.
Specifying the saturation width separately allows directly saturating
to the correct width.

There are two baseline expansions for the fp_to_xint_sat opcodes. If
the integer bounds can be exactly represented in the float type and
fminnum/fmaxnum are legal, we can expand to something like:

    f = fmaxnum f, FP(MIN)
    f = fminnum f, FP(MAX)
    i = fptoxi f
    i = select f uo f, 0, i # unnecessary if unsigned as 0 = MIN

If the bounds cannot be exactly represented, we expand to something
like this instead:

    i = fptoxi f
    i = select f ult FP(MIN), MIN, i
    i = select f ogt FP(MAX), MAX, i
    i = select f uo f, 0, i # unnecessary if unsigned as 0 = MIN

It should be noted that this expansion assumes a non-trapping fptoxi.

Initial tests are for AArch64, x86_64 and ARM. This exercises all of
the scalar and vector legalization. ARM is included to test float
softening.

Original patch by @nikic and @ebevhan (based on D54696).

Differential Revision: https://reviews.llvm.org/D54749
2020-12-18 11:09:41 +01:00
Rong Xu 3733463dbb [IR][PGO] Add hot func attribute and use hot/cold attribute in func section
Clang FE currently has hot/cold function attribute. But we only have
cold function attribute in LLVM IR.

This patch adds support of hot function attribute to LLVM IR.  This
attribute will be used in setting function section prefix/suffix.
Currently .hot and .unlikely suffix only are added in PGO (Sample PGO)
compilation (through isFunctionHotInCallGraph and
isFunctionColdInCallGraph).

This patch changes the behavior. The new behavior is:
(1) If the user annotates a function as hot or isFunctionHotInCallGraph
    is true, this function will be marked as hot. Otherwise,
(2) If the user annotates a function as cold or
    isFunctionColdInCallGraph is true, this function will be marked as
    cold.

The changes are:
(1) user annotated function attribute will used in setting function
    section prefix/suffix.
(2) hot attribute overwrites profile count based hotness.
(3) profile count based hotness overwrite user annotated cold attribute.

The intention for these changes is to provide the user a way to mark
certain function as hot in cases where training input is hard to cover
all the hot functions.

Differential Revision: https://reviews.llvm.org/D92493
2020-12-17 18:41:12 -08:00
Layton Kifer 385e9a2a04 [DAGCombiner] Improve shift by select of constant
Clean up a TODO, to support folding a shift of a constant by a
select of constants, on targets with different shift operand sizes.

Reviewed By: RKSimon, lebedev.ri

Differential Revision: https://reviews.llvm.org/D90349
2020-12-18 02:21:42 +00:00
dfukalov 9ed8e0caab [NFC] Reduce include files dependency and AA header cleanup (part 2).
Continuing work started in https://reviews.llvm.org/D92489:

Removed a bunch of includes from "AliasAnalysis.h" and "LoopPassManager.h".

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D92852
2020-12-17 14:04:48 +03:00