Commit Graph

117 Commits

Author SHA1 Message Date
Florian Hahn
09bcc572cb [VPlan] Add VPRecipeBase::mayHaveSideEffects.
Add an initial version of a helper to determine whether a recipe may
have side-effects.

Reviewed By: a.elovikov

Differential Revision: https://reviews.llvm.org/D100259
2021-04-15 11:49:40 +01:00
Florian Hahn
99c48b5190 [VPlan] Print VPValue operands for VPWidenPHI if possible.
For VPWidenPHIRecipes that model all incoming values as VPValue
operands, print those operands instead of printing the original PHI.

D99294 updates recipes of reduction PHIs to use the VPValue for the
incoming value from the loop backedge, making use of this new printing.
2021-04-06 12:11:21 +01:00
Florian Hahn
124f490c59 [VPlan] Include name when printing after 93a9d2de8f4f.
The name is included when printing in DOT mode. Also print it in non-DOT
mode after 93a9d2de8f4f.

This will become more important to distinguish different plans once
VPlans are gradually refined.
2021-03-23 09:50:14 +00:00
Andrei Elovikov
e11e0993d0 [NFC][VPlan] Guard print routines with "#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)"
Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D98897
2021-03-19 10:50:12 -07:00
Andrei Elovikov
c3beafcfc6 [VPlan] Add plain text (not DOT's digraph) dumps
I foresee two uses for this:
1) It's easier to use those in debugger.
2) Once we start implementing more VPlan-to-VPlan transformations (especially
   inner loop massaging stuff), using the vectorized LLVM IR as CHECK targets in
   LIT test would become too obscure. I can imagine that we'd want to CHECK
   against VPlan dumps after multiple transformations instead. That would be
   easier with plain text dumps than with DOT format.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D96628
2021-03-19 10:50:12 -07:00
Mehdi Amini
f4a95d2ee2 Revert "[VPlan] Add plain text (not DOT's digraph) dumps"
This reverts commit 6b053c9867a3ede32e51cef3ed972d5ce5b38bc0.
The build is broken:

ld.lld: error: undefined symbol: llvm::VPlan::printDOT(llvm::raw_ostream&) const
>>> referenced by LoopVectorize.cpp
>>>               LoopVectorize.cpp.o:(llvm::LoopVectorizationPlanner::printPlans(llvm::raw_ostream&)) in archive lib/libLLVMVectorize.a
2021-03-18 19:20:39 +00:00
Andrei Elovikov
dd2983046b [VPlan] Add plain text (not DOT's digraph) dumps
I foresee two uses for this:
1) It's easier to use those in debugger.
2) Once we start implementing more VPlan-to-VPlan transformations (especially
   inner loop massaging stuff), using the vectorized LLVM IR as CHECK targets in
   LIT test would become too obscure. I can imagine that we'd want to CHECK
   against VPlan dumps after multiple transformations instead. That would be
   easier with plain text dumps than with DOT format.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D96628
2021-03-18 11:33:39 -07:00
David Sherwood
dcd9c105f6 [SVE][LoopVectorize] Add support for extracting the last lane of a scalable vector
There are certain loops like this below:

  for (int i = 0; i < n; i++) {
    a[i] = b[i] + 1;
    *inv = a[i];
  }

that can only be vectorised if we are able to extract the last lane of the
vectorised form of 'a[i]'. For fixed width vectors this already works since
we know at compile time what the final lane is, however for scalable vectors
this is a different story. This patch adds support for extracting the last
lane from a scalable vector using a runtime determined lane value. I have
added support to VPIteration for runtime-determined lanes that still permit
the caching of values. I did this by introducing a new class called VPLane,
which describes the lane we're dealing with and provides interfaces to get
both the compile-time known lane and the runtime determined value. Whilst
doing this work I couldn't find any explicit tests for extracting the last
lane values of fixed width vectors so I added tests for both scalable and
fixed width vectors.

Differential Revision: https://reviews.llvm.org/D95139
2021-03-05 09:57:56 +00:00
Andrei Elovikov
15c77322ba [NFCI][VPlan] Modify Recipes' print methods to honor Indent parameter
Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D97787
2021-03-02 15:32:10 -08:00
Andrei Elovikov
60aa0e4593 [NFC][VPlan] Use VPUser to store block's predicate
Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D96529
2021-02-23 11:08:27 -08:00
Florian Hahn
fbfddf31c3 [VPlan] Skip VPWidenPHIRecipe in VPInterleavedACcessInfo.
Update unit tests that did not expect VPWidenPHIRecipes after
15a74b64dfa9.
2021-02-22 10:35:09 +00:00
Benjamin Kramer
ba5cce52d3 [LV] Fold single-use variable into assert. NFC. 2021-02-19 18:11:39 +01:00
Florian Hahn
832b7f4044 [LV] Remove VPCallback.
Now that all state for generated instructions is managed directly in
VPTransformState, VPCallBack is no longer needed. This patch updates the
last use of `getOrCreateScalarValue` to instead manage the value
directly in VPTransformState and removes VPCallback.

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D95383
2021-02-19 12:50:41 +00:00
Florian Hahn
90a5f6130c [VPlan] Manage scalarized values using VPValues.
This patch updates codegen to use VPValues to manage the generated
scalarized instructions.

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D92285
2021-02-16 09:04:10 +00:00
Florian Hahn
b4a7561ae7 [VPlan] Make VPRecipeBase inherit from VPUser directly (NFC).
The individual recipes have been updated to manage their operands using
VPUser a while back. Now that the transition is done, we can instead
make VPRecipeBase a VPUser and get rid of the toVPUser helper.
2021-02-12 13:06:58 +00:00
Florian Hahn
dac217d015 [VPlan] Use VPUser to manage CondBit
VP blocks keep track of a condition, which is a VPValue. This patch
updates VPBlockBase to manage the value using VPUser, so
replaceAllUsesWith properly updates the condition bit as well.

This is required to enable VP2VP transformations and it helps with
simplifying some of the code required to manage condition bits.

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D95382
2021-02-09 21:53:50 +00:00
Florian Hahn
52a13d4927 [VPlan] Manage induction value creation using VPValues.
This patch updates the induction value creation to use VPValues of
recipes to map the created values. This should bring is one step closer
to being able to optimize induction recipes directly in VPlan.

Currently widenIntOrFpInduction also generates vector values for a cast
of the induction, if it exists. Make this explicit by adding the cast
instruction to the values defined by the recipe.

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D92284
2021-02-03 17:45:03 +00:00
David Sherwood
9ead40bd43 [VPlan][NFC] Introduce constructors for VPIteration
This patch adds constructors to VPIteration as a cleaner way of
initialising the struct and replaces existing constructions of
the form:

  {Part, Lane}

with

  VPIteration(Part, Lane)

I have also added a default constructor, which is used by VPlan.cpp
when deciding whether to replicate a block or not.

This refactoring will be required in a later patch that adds more
members and functions to VPIteration.

Differential Revision: https://reviews.llvm.org/D95676
2021-02-03 08:52:27 +00:00
Florian Hahn
804ecf1ca5 [VPlan] Handle scalarized values in VPTransformState.
This patch adds plumbing to handle scalarized values directly in
VPTransformState.

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D92282
2021-01-25 14:21:56 +00:00
Kazu Hirata
8b192f274e [llvm] Construct SmallVector with iterator ranges (NFC) 2021-01-16 09:40:53 -08:00
Florian Hahn
7ccaba4adc [VPlan] Unify value/recipe printing after VPDef transition.
This patch unifies the way recipes and VPValues are printed after the
transition to VPDef.

VPSlotTracker has been updated to iterate over all recipes and all
their defined values to number those. There is no need to number
values in Value2VPValue.

It also updates a few places that only used slot numbers for
VPInstruction. All recipes now can produce numbered VPValues.
2021-01-11 14:42:46 +00:00
Florian Hahn
ac116375b4 [VPlan] Move initial quote emission from ::print to ::dumpBasicBlock.
This means there will be no stray " when printing individual recipes
using print()/dump() in a debugger, for example.
2021-01-11 12:22:15 +00:00
David Green
40a4684746 [LV] Don't sink into replication regions
The new test case here contains a first order recurrences and an
instruction that is replicated. The first order recurrence forces an
instruction to be sunk _into_, as opposed to after the replication
region. That causes several things to go wrong including registering
vector instructions multiple times and failing to create dominance
relations correctly.

Instead we should be sinking to after the replication region, which is
what this patch makes sure happens.

Differential Revision: https://reviews.llvm.org/D93629
2021-01-08 09:50:10 +00:00
Sanjay Patel
eafc7203b6 [LoopUtils] remove redundant opcode parameter; NFC
While here, rename the inaccurate getRecurrenceBinOp()
because that was also used to get CmpInst opcodes.

The recurrence/reduction kind should always refer to the
expected opcode for a reduction. SLP appears to be the
only direct caller of createSimpleTargetReduction(), and
that calling code ideally should not be carrying around
both an opcode and a reduction kind.

This should allow us to generalize reduction matching to
use intrinsics instead of only binops.
2021-01-04 17:05:28 -05:00
Florian Hahn
f84e692f2b [VPlan] Make VPInstruction a VPDef
This patch turns updates VPInstruction to manage the value it defines
using VPDef. The VPValue is used  during VPlan construction and
codegeneration instead of the plain IR reference where possible.

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D90565
2020-12-22 09:53:47 +00:00
Florian Hahn
2c9bb42ba6 [VPlan] Make VPRecipeBase inherit from VPDef.
This patch makes VPRecipeBase a direct subclass of VPDef, moving the
SubclassID to VPDef.

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D90564
2020-12-21 13:34:00 +00:00
Florian Hahn
e5ba40d3e8 [VPlan] Use VPDef for VPInterleaveRecipe.
This patch turns updates VPInterleaveRecipe to manage the values it defines
using VPDef. The VPValue is used  during VPlan construction and
codegeneration instead of the plain IR reference where possible.

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D90562
2020-12-21 10:56:53 +00:00
Florian Hahn
8b3b1f6f2e [VPlan] Make VPWidenMemoryInstructionRecipe a VPDef.
This patch updates VPWidenMemoryInstructionRecipe to use VPDef
to manage the value it produces instead of inheriting from VPValue.

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D90563
2020-12-14 14:13:59 +00:00
Florian Hahn
89cd0fd6c4 [VPlan] Use interleaveComma in printOperands() (NFC). 2020-12-13 16:29:16 +00:00
Florian Hahn
816af73eeb [VPlan] Use VPUser to manage VPPredInstPHIRecipe operand (NFC).
VPPredInstPHIRecipe is one of the recipes that was missed during the
initial conversion. This patch adjusts the recipe to also manage its
operand using VPUser.
2020-11-30 13:09:58 +00:00
Florian Hahn
ffd8b60920 [VPlan] Use VPValue and VPUser ops to print VPReplicateRecipe. 2020-11-29 18:28:27 +00:00
Florian Hahn
0e7cb2bfc6 [VPlan] Turn VPReplicateRecipe into a VPValue.
Update VPReplicateRecipe to inherit from VPValue. This still does not
update scalarizeInstruction to set the result for the VPValue of
VPReplicateRecipe, because this first requires tracking scalar values in
VPTransformState.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D91500
2020-11-26 13:50:24 +00:00
David Green
e9de6b6f53 [VPlan] Switch VPWidenRecipe to be a VPValue
Similar to other patches, this makes VPWidenRecipe a VPValue. Because of
the way it interacts with the reduction code it also slightly alters the
way that VPValues are registered, removing the up front NeedDef and
using getOrAddVPValue to create them on-demand if needed instead.

Differential Revision: https://reviews.llvm.org/D88447
2020-11-25 08:25:06 +00:00
David Green
0890a0e099 [VPlan] Turn VPReductionRecipe into a VPValue
This converts the VPReductionRecipe into a VPValue, like other
VPRecipe's in preparation for traversing def-use chains. It also makes
it a VPUser, now storing the used VPValues as operands.

It doesn't yet change how the VPReductionRecipes are created. It will
need to call replaceAllUsesWith from the original recipe they replace,
but that is not done yet as VPWidenRecipe need to be created first.

Differential Revision: https://reviews.llvm.org/D88382
2020-11-25 08:25:05 +00:00
Florian Hahn
4864887dc5 [VPlan] Add VPDef class.
This patch introduces a new VPDef class, which can be used to
manage VPValues defined by recipes/VPInstructions.

The idea here is to mirror VPUser for values defined by a recipe. A
VPDef can produce either zero (e.g. a store recipe), one (most recipes)
or multiple (VPInterleaveRecipe) result VPValues.

To traverse the def-use chain from a VPDef to its users, one has to
traverse the users of all values defined by a VPDef.

VPValues now contain a pointer to their corresponding VPDef, if one
exists. To traverse the def-use chain upwards from a VPValue, we first
need to check if the VPValue is defined by a VPDef. If it does not have
a VPDef, this means we have a VPValue that is not directly defined
iniside the plan and we are done.

If we have a VPDef, it is defined inside the region by a recipe, which
is a VPUser, and the upwards def-use chain traversal continues by
traversing all its operands.

Note that we need to add an additional field to to VPVAlue to link them
to their defs. The space increase is going to be offset by being able to
remove the SubclassID field in future patches.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D90558
2020-11-17 16:18:11 +00:00
Florian Hahn
df302df8f2 [VPlan] Use VPValue def for VPWidenGEPRecipe.
This patch turns VPWidenGEPRecipe into a VPValue and uses it
during VPlan construction and codegeneration instead of the plain IR
reference where possible.

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D84683
2020-11-15 15:12:47 +00:00
Florian Hahn
19840b7955 Recommit "[VPlan] Use VPValue def for VPWidenSelectRecipe."
This reverts the revert commit c8d73d939fa4fda9c87b3979225d02d63062bd68.

It includes a fix for cases where we missed inserting VPValues
for some selects, which should fix PR48142.
2020-11-14 20:00:25 +00:00
Florian Hahn
9a4f506dca Revert "[VPlan] Use VPValue def for VPWidenSelectRecipe."
This reverts commit a8e50f1c6e7b404aab8fedb972f003a4d6a6434e.

This reportedly breaks building the Linux kernel.
  https://bugs.llvm.org/show_bug.cgi?id=48142
2020-11-10 22:50:46 +00:00
Florian Hahn
9d663d0250 [VPlan] Use VPValue def for VPWidenSelectRecipe.
This patch turns VPWidenSelectRecipe into a VPValue and uses it
during VPlan construction and codegeneration instead of the plain IR
reference where possible.

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D84682
2020-11-10 19:39:37 +00:00
Florian Hahn
a912c32467 [VPlan] Print result value for loads in VPWidenMemoryInst (NFC).
For loads, print the result value.
2020-11-09 14:01:29 +00:00
Florian Hahn
1c03782e21 [VPlan] Use VPValue def for VPWidenCall.
This patch turns VPWidenCall into a VPValue and uses it
during VPlan construction and codegeneration instead of the plain IR
reference where possible.

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D84681
2020-11-09 13:29:41 +00:00
Florian Hahn
a9b449ce40 [VPlan] Add printOperands helper to VPUser (NFC).
Factor out the code for printing operands of a VPUser so it can be
re-used when printing other recipes.
2020-11-09 12:30:57 +00:00
Florian Hahn
f1c34f2040 [VPlan] Use isa<> instead getVPRecipeID in getFirstNonPhi (NFC).
As per the comment in VPRecipeBase, clients should not rely on
getVPRecipeID, as it may change in the future. It should only be used in
classof implementations. Use isa instead in getFirstNonPhi.
2020-10-30 14:56:06 +00:00
Florian Hahn
b608aa34a1 Recommit "[VPlan] Use VPValue def for VPMemoryInstructionRecipe."
This reverts the revert commit 710aceb645e7dba4de7053eef2c616311b9163d4
and includes a fix for a memsan failure.

Original message:

    This patch turns VPMemoryInstructionRecipe into a VPValue and uses it
    during VPlan construction and codegeneration instead of the plain IR
    reference where possible.
2020-10-14 17:41:23 +01:00
Vitaly Buka
3d279fb5a5 Revert "[VPlan] Use VPValue def for VPMemoryInstructionRecipe."
It introduced a memory leak.

This reverts commit 525b085a65d30a5f2ae2af38c0be252fe8d4781b.
2020-10-13 03:14:08 -07:00
Florian Hahn
daadcb3953 [VPlan] Use VPValue def for VPMemoryInstructionRecipe.
This patch turns VPMemoryInstructionRecipe into a VPValue and uses it
during VPlan construction and codegeneration instead of the plain IR
reference where possible.

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D84680
2020-10-12 18:02:33 +01:00
Florian Hahn
9589bcce9e [VPlan] Use operands for printing of VPWidenMemoryInstructionRecipe.
Now that operands of the recipe are managed through VPUser, we can
simplify the printing by just using the operands.
2020-10-12 16:51:54 +01:00
David Sherwood
9a012ebf36 [SVE] Make ElementCount and TypeSize use a new PolySize class
I have introduced a new template PolySize class, where the template
parameter determines the type of quantity, i.e. for an element
count this is just an unsigned value. The ElementCount class is
now just a simple derivation of PolySize<unsigned>, whereas TypeSize
is more complicated because it still needs to contain the uint64_t
cast operator, since there are still many places in the code that
rely upon this implicit cast. As such the class also still needs
some of it's own operators.

I've tried to minimise the amount of code in the base PolySize
class, which led to a couple of changes:

1. In some places we were relying on '==' operator comparisons
between ElementCounts and the scalar value 1. I didn't put this
operator in the new PolySize class, and thought it was actually
clearer to use the isScalar() function instead.
2. I removed the isByteSized function and replaced it with calls
to isKnownMultipleOf(8).

I've also renamed NextPowerOf2 to be coefficientNextPowerOf2 so
that it's more consistent with coefficientDivideBy.

Differential Revision: https://reviews.llvm.org/D88409
2020-10-12 08:23:38 +01:00
David Green
15eddfee76 [LV] Tail folded inloop reductions.
This expands upon the inloop reductions added in e9761688e41cb9e976,
allowing them to be inserted into tail folded loops. Reductions are
generates with the form:

  x = select(mask, vecop, zero)
  v = vecreduce.add(x)
  c = add chain, v

Where zero here is chosen as the identity value for add reductions. The
backend is then expected to fold the select and the vecreduce into a
single predicated instruction.

Most of the code is fairly straight forward, except for the creation of
blockmasks which need to ensure they are created in dominance order. The
order they are added is altered to be after any phis, keeping the
requirements for the underlying IR.

Differential Revision: https://reviews.llvm.org/D84451
2020-10-11 16:58:34 +01:00
Florian Hahn
000449765c [VPlan] Clean up uses/operands on VPBB deletion.
Update the code responsible for deleting VPBBs and recipes to properly
update users and release operands.

This is another preparation for D84680 & following patches towards
enabling modeling def-use chains in VPlan.
2020-10-05 14:43:52 +01:00