Commit Graph

71 Commits

Author SHA1 Message Date
Jessica Paquette 2d73ecd0a3 [GlobalISel][AArch64] Add legalization for G_FLOG
This adds support for legalizing G_FLOG into a RTLib call.

It adds a legalizer test, and updates the existing floating point tests.

https://reviews.llvm.org/D57347

llvm-svn: 352429
2019-01-28 21:27:23 +00:00
Jessica Paquette c49428a97d [GlobalISel][AArch64] Add instruction selection support for @llvm.log10
This adds instruction selection support for @llvm.log10 in AArch64. It teaches
GISel to lower it to a library call, updates the relevant tests, and adds a
legalizer test for log10.

https://reviews.llvm.org/D57341

llvm-svn: 352418
2019-01-28 19:53:14 +00:00
Jessica Paquette 7db82d7257 [GlobalISel][AArch64] Add instruction selection support for G_FCOS and G_FSIN
This contains all of the legalizer changes from D57197 necessary to select
G_FCOS and G_FSIN. It also updates several existing IR tests in
test/CodeGen/AArch64 that verify that we correctly lower the G_FCOS and G_FSIN
instructions.

https://reviews.llvm.org/D57197
3/3

llvm-svn: 352402
2019-01-28 18:34:18 +00:00
Amara Emerson 0bfa2faccc [AArch64][GlobalISel] Add some missing vector support for FP arithmetic ops.
Moved the fneg lowering legalization test from AArch64 to X86, as we want to
specify that it's already legal.

llvm-svn: 352338
2019-01-28 02:28:22 +00:00
Amara Emerson 92ffb305cc [AArch64][GlobalISel] Add some vector support for fp <-> int conversions.
Some unrelated, but benign, test changes as well due to the test update script.

llvm-svn: 352337
2019-01-28 02:27:59 +00:00
Matt Arsenault 990f507704 GlobalISel: Add convenience mutatations to scalarize
llvm-svn: 352143
2019-01-25 00:51:00 +00:00
Jessica Paquette 245047dfe8 [GlobalISel][AArch64] Add isel support for FP16 vector @llvm.ceil
This patch adds support for vector @llvm.ceil intrinsics when full 16 bit
floating point support isn't available.

To do this, this patch...

- Implements basic isel for G_UNMERGE_VALUES
- Teaches the legalizer about 16 bit floats
- Teaches AArch64RegisterBankInfo to respect floating point registers on
  G_BUILD_VECTOR and G_UNMERGE_VALUES
- Teaches selectCopy about 16-bit floating point vectors

It also adds

- A legalizer test for the 16-bit vector ceil which verifies that we create a
  G_UNMERGE_VALUES and G_BUILD_VECTOR when full fp16 isn't supported
- An instruction selection test which makes sure we lower to G_FCEIL when
  full fp16 is supported
- A test for selecting G_UNMERGE_VALUES

And also updates arm64-vfloatintrinsics.ll to show that the new ceiling types
work as expected.

https://reviews.llvm.org/D56682

llvm-svn: 352113
2019-01-24 22:00:41 +00:00
Matt Arsenault 30989e492b GlobalISel: Allow shift amount to be a different type
For AMDGPU the shift amount is never 64-bit, and
this needs to use a 32-bit shift.

X86 uses i8, but seemed to be hacking around this before.

llvm-svn: 351882
2019-01-22 21:42:11 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Matt Arsenault 3dddb163dd GlobalISel: Implement fewerElements for implicit_def
llvm-svn: 350697
2019-01-09 07:51:52 +00:00
Jessica Paquette 453ab1db5b [GlobalISel][AArch64] Add support for widening G_FCEIL
This adds support for widening G_FCEIL in LegalizerHelper and
AArch64LegalizerInfo. More specifically, it teaches the AArch64 legalizer to
widen G_FCEIL from a 16-bit float to a 32-bit float when the subtarget doesn't
support full FP 16.

This also updates AArch64/f16-instructions.ll to show that we perform the
correct transformation.

llvm-svn: 349927
2018-12-21 17:05:26 +00:00
Jessica Paquette 3560e93dc1 [GlobalISel][AArch64] Add support for @llvm.ceil
This adds a G_FCEIL generic instruction and uses it in AArch64. This adds
selection for floating point ceil where it has a supported, dedicated
instruction. Other cases aren't handled here.

It updates the relevant gisel tests and adds a select-ceil test. It also adds a
check to arm64-vcvt.ll which ensures that we don't fall back when we run into
one of the relevant cases.

llvm-svn: 349664
2018-12-19 19:01:36 +00:00
Amara Emerson 5ec146046c [GlobalISel] Restrict G_MERGE_VALUES capability and replace with new opcodes.
This patch restricts the capability of G_MERGE_VALUES, and uses the new
G_BUILD_VECTOR and G_CONCAT_VECTORS opcodes instead in the appropriate places.

This patch also includes AArch64 support for selecting G_BUILD_VECTOR of <4 x s32>
and <2 x s64> vectors.

Differential Revisions: https://reviews.llvm.org/D53629

llvm-svn: 348788
2018-12-10 18:44:58 +00:00
Aditya Nandakumar f75d4f329c [GISel]: Provide standard interface to observe changes in GISel passes
https://reviews.llvm.org/D54980

This provides a standard API across GISel passes to observe and notify
passes about changes (insertions/deletions/mutations) to MachineInstrs.
This patch also removes the recordInsertion method in MachineIRBuilder
and instead provides method to setObserver.

Reviewed by: vkeles.

llvm-svn: 348406
2018-12-05 20:14:52 +00:00
Volkan Keles 0a8dc9eb0f [GlobalISel] Fix a bug in LegalizeRuleSet::clampMaxNumElements
Summary:
This function was causing a crash when `MaxElements == 1` because
it was trying to create a single element vector type.

Reviewers: dsanders, aemerson, aditya_nandakumar

Reviewed By: dsanders

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

Differential Revision: https://reviews.llvm.org/D53734

llvm-svn: 345875
2018-11-01 19:01:53 +00:00
Volkan Keles f87473fe1c [GISel] LegalizerInfo: Rename MemDesc::Size to SizeInBits to make the value clearer
Requested in D53679.

llvm-svn: 345288
2018-10-25 17:37:07 +00:00
Volkan Keles 3a103b1d25 [AArch64][GlobalISel] Fix the LegalityPredicate for lowerIf for G_LOAD/G_STORE
Summary:
Currently, Legalizer is trying to lower G_LOAD with a vector type
that has more than two elements due to the incorrect LegalityPredicate.

This patch fixes the issue by removing the multiplication by 8
as `MemDesc.Size` already contains the size in bits.

Reviewers: dsanders, aemerson

Reviewed By: dsanders

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

Differential Revision: https://reviews.llvm.org/D53679

llvm-svn: 345282
2018-10-25 17:23:25 +00:00
Amara Emerson cbd86d8429 [GlobalISel] Use the target preferred type for G_EXTRACT_VECTOR_ELT index.
Allows for better imported pattern re-use.

llvm-svn: 345265
2018-10-25 14:04:54 +00:00
Amara Emerson 0e86c07077 [AArch64][GlobalISel] Make G_BLOCK_ADDR legal.
Differential Revision: https://reviews.llvm.org/D49902

llvm-svn: 338336
2018-07-31 00:08:56 +00:00
Daniel Sanders bdeb880d14 [globalisel][legalizer] Add AtomicOrdering to LegalityQuery and use it in AArch64
Now that we have the ability to legalize based on MMO's. Add support for
legalizing based on AtomicOrdering and use it to correct the legalization
of the atomic instructions.

Also extend all() to be a variadic template as this ruleset now requires
3 and 4 argument versions.

llvm-svn: 335767
2018-06-27 19:03:21 +00:00
Roman Tereshin 5a65eb75c7 [GlobalISel][AArch64] LegalizerInfo verifier: Fixing bugs exposed by LegalizerInfo::verify(...)
Reviewers: aemerson, qcolombet

Reviewed By: qcolombet

Differential Revision: https://reviews.llvm.org/D46339

llvm-svn: 333618
2018-05-31 01:56:05 +00:00
Roman Tereshin 8f1753e994 [GlobalISel][AArch64] LegalizerInfo verifier: Adding LegalizerInfo::verify(...) call w/o fixing bugs
This is to make it clear what kind of bugs the LegalizerInfo::verifier
is able to catch and test its output

Reviewers: aemerson, qcolombet

Reviewed By: aemerson

Differential Revision: https://reviews.llvm.org/D46338

llvm-svn: 333597
2018-05-30 22:10:04 +00:00
Daniel Sanders f84bc3793e [globalisel] Update GlobalISel emitter to match new representation of extending loads
Summary:
Previously, a extending load was represented at (G_*EXT (G_LOAD x)).
This had a few drawbacks:
* G_LOAD had to be legal for all sizes you could extend from, even if
  registers didn't naturally hold those sizes.
* All sizes you could extend from had to be allocatable just in case the
  extend went missing (e.g. by optimization).
* At minimum, G_*EXT and G_TRUNC had to be legal for these sizes. As we
  improve optimization of extends and truncates, this legality requirement
  would spread without considerable care w.r.t when certain combines were
  permitted.
* The SelectionDAG importer required some ugly and fragile pattern
  rewriting to translate patterns into this style.

This patch changes the representation to:
* (G_[SZ]EXTLOAD x)
* (G_LOAD x) any-extends when MMO.getSize() * 8 < ResultTy.getSizeInBits()
which resolves these issues by allowing targets to work entirely in their
native register sizes, and by having a more direct translation from
SelectionDAG patterns.

Each extending load can be lowered by the legalizer into separate extends
and loads, however a target that supports s1 will need the any-extending
load to extend to at least s8 since LLVM does not represent memory accesses
smaller than 8 bit. The legalizer can widenScalar G_LOAD into an
any-extending load but sign/zero-extending loads need help from something
else like a combiner pass. A follow-up patch that adds combiner helpers for
for this will follow.

The new representation requires that the MMO correctly reflect the memory
access so this has been corrected in a couple tests. I've also moved the
extending loads to their own tests since they are (mostly) separate opcodes
now. Additionally, the re-write appears to have invalidated two tests from
select-with-no-legality-check.mir since the matcher table no longer contains
loads that result in s1's and they aren't legal in AArch64 anymore.

Depends on D45540

Reviewers: ab, aditya_nandakumar, bogner, rtereshin, volkan, rovka, javed.absar

Reviewed By: rtereshin

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

Differential Revision: https://reviews.llvm.org/D45541

llvm-svn: 331601
2018-05-05 20:53:24 +00:00
Daniel Sanders 2de9d4ad5d Fix infinite loop after r331115
There are two separate fixes here:
* The lowering code for non-extending loads should report UnableToLegalize instead of emitting the same instruction.
* The target should not be requesting lowering of non-extending loads.

llvm-svn: 331201
2018-04-30 17:20:01 +00:00
Daniel Sanders 5eb9f581b6 [globalisel][legalizerinfo] Introduce dedicated extending loads and add lowerings for them
Summary:
Previously, a extending load was represented at (G_*EXT (G_LOAD x)).
This had a few drawbacks:
* G_LOAD had to be legal for all sizes you could extend from, even if
  registers didn't naturally hold those sizes.
* All sizes you could extend from had to be allocatable just in case the
  extend went missing (e.g. by optimization).
* At minimum, G_*EXT and G_TRUNC had to be legal for these sizes. As we
  improve optimization of extends and truncates, this legality requirement
  would spread without considerable care w.r.t when certain combines were
  permitted.
* The SelectionDAG importer required some ugly and fragile pattern
  rewriting to translate patterns into this style.

This patch begins changing the representation to:
* (G_[SZ]EXTLOAD x)
* (G_LOAD x) any-extends when MMO.getSize() * 8 < ResultTy.getSizeInBits()
which resolves these issues by allowing targets to work entirely in their
native register sizes, and by having a more direct translation from
SelectionDAG patterns.

This patch introduces the new generic instructions and new variation on
G_LOAD and adds lowering for them to convert back to the existing
representations.

Depends on D45466

Reviewers: ab, aditya_nandakumar, bogner, rtereshin, volkan, rovka, aemerson, javed.absar

Reviewed By: aemerson

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

Differential Revision: https://reviews.llvm.org/D45540

llvm-svn: 331115
2018-04-28 18:14:50 +00:00
Daniel Sanders 27fe8a5011 [globalisel][legalizerinfo] Add support for legalization based on the MachineMemOperand
Summary:
Currently only the memory size is supported but others can be added as
needed.

narrowScalar for G_LOAD and G_STORE now correctly update the
MachineMemOperand and will refuse to legalize atomics since those need more
careful expansions to maintain atomicity.

Reviewers: ab, aditya_nandakumar, bogner, rtereshin, aemerson, javed.absar

Reviewed By: aemerson

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

Differential Revision: https://reviews.llvm.org/D45466

llvm-svn: 331071
2018-04-27 19:48:53 +00:00
Daniel Sanders 5281b02e84 [globalisel][legalizerinfo] Add support for the Lower action in getActionDefinitionsBuilder() and use it in AArch64.
Lower is slightly odd. It often doesn't change the type but the lowerings
do use the new type to decide what code to create. Treat it like a mutation
but provide convenience functions that re-use the existing type.

Re-uses the existing tests:
test/CodeGen/AArch64/GlobalISel/legalize-rem.mir
test/CodeGen/AArch64/GlobalISel//legalize-mul.mir
test/CodeGen/AArch64/GlobalISel//legalize-cmpxchg-with-success.mir

llvm-svn: 329623
2018-04-09 21:10:09 +00:00
Craig Topper 2fa1436206 [IR][CodeGen] Remove dependency on EVT from IR/Function.cpp. Move EVT to CodeGen layer.
Currently EVT is in the IR layer only because of Function.cpp needing a very small piece of the functionality of EVT::getEVTString(). The rest of EVT is used in codegen making CodeGen a better place for it.

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

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

llvm-svn: 328806
2018-03-29 17:21:10 +00:00
David Blaikie 36a0f226b1 Fix layering by moving ValueTypes.h from CodeGen to IR
ValueTypes.h is implemented in IR already.

llvm-svn: 328397
2018-03-23 23:58:31 +00:00
Daniel Sanders 7fc87360e9 [globalisel][legalizerinfo] Follow up on post-commit review comments after r323681
* Document most API's
* Delete a useless function call
* Fix a discrepancy between the single and multi-opcode variants of
  getActionDefinitions().
  The multi-opcode variant now requires that more than one opcode is requested.
  Previously it acted much like the single-opcode form but unnecessarily
  enforced the requirements of the multi-opcode form.

llvm-svn: 325067
2018-02-13 23:02:44 +00:00
Daniel Sanders 79cb839fcd [globalisel][legalizer] Adapt LegalizerInfo to support inter-type dependencies and other things.
Summary:
As discussed in D42244, we have difficulty describing the legality of some
operations. We're not able to specify relationships between types.
For example, declaring the following
  setAction({..., 0, s32}, Legal)
  setAction({..., 0, s64}, Legal)
  setAction({..., 1, s32}, Legal)
  setAction({..., 1, s64}, Legal)
currently declares these type combinations as legal:
  {s32, s32}
  {s64, s32}
  {s32, s64}
  {s64, s64}
but we currently have no means to say that, for example, {s64, s32} is
not legal. Some operations such as G_INSERT/G_EXTRACT/G_MERGE_VALUES/
G_UNMERGE_VALUES have relationships between the types that are currently
described incorrectly.
    
Additionally, G_LOAD/G_STORE currently have no means to legalize non-atomics
differently to atomics. The necessary information is in the MMO but we have no
way to use this in the legalizer. Similarly, there is currently no way for the
register type and the memory type to differ so there is no way to cleanly
represent extending-load/truncating-store in a way that can't be broken by
optimizers (resulting in illegal MIR).

It's also difficult to control the legalization strategy. We've added support
for legalizing non-power of 2 types but there's still some hardcoded assumptions
about the strategy. The main one I've noticed is that type0 is always legalized
before type1 which is not a good strategy for `type0 = G_EXTRACT type1, ...` if
you need to widen the container. It will converge on the same result eventually
but it will take a much longer route when legalizing type0 than if you legalize
type1 first.

Lastly, the definition of legality and the legalization strategy is kept
separate which is not ideal. It's helpful to be able to look at a one piece of
code and see both what is legal and the method the legalizer will use to make
illegal MIR more legal.

This patch adds a layer onto the LegalizerInfo (to be removed when all targets
have been migrated) which resolves all these issues.

Here are the rules for shift and division:
  for (unsigned BinOp : {G_LSHR, G_ASHR, G_SDIV, G_UDIV})
    getActionDefinitions(BinOp)
        .legalFor({s32, s64})     // If type0 is s32/s64 then it's Legal
        .clampScalar(0, s32, s64) // If type0 is <s32 then WidenScalar to s32
                                  // If type0 is >s64 then NarrowScalar to s64
        .widenScalarToPow2(0)     // Round type0 scalars up to powers of 2
        .unsupported();           // Otherwise, it's unsupported
This describes everything needed to both define legality and describe how to
make illegal things legal.

Here's an example of a complex rule:
  getActionDefinitions(G_INSERT)
      .unsupportedIf([=](const LegalityQuery &Query) {
        // If type0 is smaller than type1 then it's unsupported
        return Query.Types[0].getSizeInBits() <= Query.Types[1].getSizeInBits();
      })
      .legalIf([=](const LegalityQuery &Query) {
        // If type0 is s32/s64/p0 and type1 is a power of 2 other than 2 or 4 then it's legal
        // We don't need to worry about large type1's because unsupportedIf caught that.
        const LLT &Ty0 = Query.Types[0];
        const LLT &Ty1 = Query.Types[1];
        if (Ty0 != s32 && Ty0 != s64 && Ty0 != p0)
          return false;
        return isPowerOf2_32(Ty1.getSizeInBits()) &&
               (Ty1.getSizeInBits() == 1 || Ty1.getSizeInBits() >= 8);
      })
      .clampScalar(0, s32, s64)
      .widenScalarToPow2(0)
      .maxScalarIf(typeInSet(0, {s32}), 1, s16) // If type0 is s32 and type1 is bigger than s16 then NarrowScalar type1 to s16
      .maxScalarIf(typeInSet(0, {s64}), 1, s32) // If type0 is s64 and type1 is bigger than s32 then NarrowScalar type1 to s32
      .widenScalarToPow2(1)                     // Round type1 scalars up to powers of 2
      .unsupported();
This uses a lambda to say that G_INSERT is unsupported when type0 is bigger than
type1 (in practice, this would be a default rule for G_INSERT). It also uses one
to describe the legal cases. This particular predicate is equivalent to:
  .legalFor({{s32, s1}, {s32, s8}, {s32, s16}, {s64, s1}, {s64, s8}, {s64, s16}, {s64, s32}})

In terms of performance, I saw a slight (~6%) performance improvement when
AArch64 was around 30% ported but it's pretty much break even right now.
I'm going to take a look at constexpr as a means to reduce the initialization
cost.

Future work:
* Make it possible for opcodes to share rulesets. There's no need for
  G_LSHR/G_ASHR/G_SDIV/G_UDIV to have separate rule and ruleset objects. There's
  no technical barrier to this, it just hasn't been done yet.
* Replace the type-index numbers with an enum to get .clampScalar(Type0, s32, s64)
* Better names for things like .maxScalarIf() (clampMaxScalar?) and the vector rules.
* Improve initialization cost using constexpr

Possible future work:
* It's possible to make these rulesets change the MIR directly instead of
  returning a description of how to change the MIR. This should remove a little
  overhead caused by parsing the description and routing to the right code, but
  the real motivation is that it removes the need for LegalizeAction::Custom.
  With Custom removed, there's no longer a requirement that Custom legalization
  change the opcode to something that's considered legal.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar, volkan, reames, bogner

Reviewed By: bogner

Subscribers: hintonda, bogner, aemerson, mgorny, javed.absar, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D42251

llvm-svn: 323681
2018-01-29 19:54:49 +00:00
Daniel Sanders 9ade5592d9 [globalisel] Make LegalizerInfo::LegalizeAction available outside of LegalizerInfo. NFC
Summary:
The improvements to the LegalizerInfo discussed in D42244 require that
LegalizerInfo::LegalizeAction be available for use in other classes. As such,
it needs to be moved out of LegalizerInfo. This has been done separately to the
next patch to minimize the noise in that patch.

llvm-svn: 323669
2018-01-29 17:37:29 +00:00
Daniel Sanders 3c1c4c0ee0 Revert r319691: [globalisel][tablegen] Split atomic load/store into separate opcode and enable for AArch64.
Some concerns were raised with the direction. Revert while we discuss it and look into an alternative

llvm-svn: 319739
2017-12-05 05:52:07 +00:00
Daniel Sanders 04e4f47e93 [globalisel][tablegen] Split atomic load/store into separate opcode and enable for AArch64.
This patch splits atomics out of the generic G_LOAD/G_STORE and into their own
G_ATOMIC_LOAD/G_ATOMIC_STORE. This is a pragmatic decision rather than a
necessary one. Atomic load/store has little in implementation in common with
non-atomic load/store. They tend to be handled very differently throughout the
backend. It also has the nice side-effect of slightly improving the common-case
performance at ISel since there's no longer a need for an atomicity check in the
matcher table.

All targets have been updated to remove the atomic load/store check from the
G_LOAD/G_STORE path. AArch64 has also been updated to mark
G_ATOMIC_LOAD/G_ATOMIC_STORE legal.

There is one issue with this patch though which also affects the extending loads
and truncating stores. The rules only match when an appropriate G_ANYEXT is
present in the MIR. For example,
  (G_ATOMIC_STORE (G_TRUNC:s16 (G_ANYEXT:s32 (G_ATOMIC_LOAD:s16 X))))
will match but:
  (G_ATOMIC_STORE (G_ATOMIC_LOAD:s16 X))
will not. This shouldn't be a problem at the moment, but as we get better at
eliminating extends/truncates we'll likely start failing to match in some
cases. The current plan is to fix this in a patch that changes the
representation of extending-load/truncating-store to allow the MMO to describe
a different type to the operation.

llvm-svn: 319691
2017-12-04 20:39:32 +00:00
Volkan Keles a32ff00b00 GlobalISel: Enable the legalization of G_MERGE_VALUES and G_UNMERGE_VALUES
Summary: LegalizerInfo assumes all G_MERGE_VALUES and G_UNMERGE_VALUES instructions are legal, so it is not possible to legalize vector operations on illegal vector types. This patch fixes the problem by removing the related check and adding default actions for G_MERGE_VALUES and G_UNMERGE_VALUES.

Reviewers: qcolombet, ab, dsanders, aditya_nandakumar, t.p.northover, kristof.beyls

Reviewed By: dsanders

Subscribers: rovka, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D39823

llvm-svn: 319524
2017-12-01 08:19:10 +00:00
Daniel Sanders aef1dfc690 [aarch64][globalisel] Legalize G_ATOMIC_CMPXCHG_WITH_SUCCESS and G_ATOMICRMW_*
G_ATOMICRMW_* is generally legal on AArch64. The exception is G_ATOMICRMW_NAND.

G_ATOMIC_CMPXCHG_WITH_SUCCESS needs to be lowered to G_ATOMIC_CMPXCHG with an
external comparison.

Note that IRTranslator doesn't generate these instructions yet.

llvm-svn: 319466
2017-11-30 20:11:42 +00:00
Simon Pilgrim 14d3fd29f8 Fix VS2017 narrowing conversion warning. NFCI
llvm-svn: 319240
2017-11-28 22:32:43 +00:00
Daniel Sanders 7fe7acc6b1 [aarch64][globalisel] Define G_ATOMIC_CMPXCHG and G_ATOMICRMW_* and make them legal
The IRTranslator cannot generate these instructions at the moment so there's no
issue with not having implemented ISel for them yet. D40092 will add
G_ATOMIC_CMPXCHG_WITH_SUCCESS and G_ATOMICRMW_* to the IRTranslator and a
further patch will add support for lowering G_ATOMIC_CMPXCHG_WITH_SUCCESS into
G_ATOMIC_CMPXCHG with an external success check via the `Lower` action.

The separation of G_ATOMIC_CMPXCHG_WITH_SUCCESS and G_ATOMIC_CMPXCHG is
to import SelectionDAG rules while still supporting targets that prefer to
custom lower the original LLVM-IR-like operation.

llvm-svn: 319216
2017-11-28 20:21:15 +00:00
David Blaikie b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
Kristof Beyls af9814a1fc [GlobalISel] Enable legalizing non-power-of-2 sized types.
This changes the interface of how targets describe how to legalize, see
the below description.

1. Interface for targets to describe how to legalize.

In GlobalISel, the API in the LegalizerInfo class is the main interface
for targets to specify which types are legal for which operations, and
what to do to turn illegal type/operation combinations into legal ones.

For each operation the type sizes that can be legalized without having
to change the size of the type are specified with a call to setAction.
This isn't different to how GlobalISel worked before. For example, for a
target that supports 32 and 64 bit adds natively:

  for (auto Ty : {s32, s64})
    setAction({G_ADD, 0, s32}, Legal);

or for a target that needs a library call for a 32 bit division:

  setAction({G_SDIV, s32}, Libcall);

The main conceptual change to the LegalizerInfo API, is in specifying
how to legalize the type sizes for which a change of size is needed. For
example, in the above example, how to specify how all types from i1 to
i8388607 (apart from s32 and s64 which are legal) need to be legalized
and expressed in terms of operations on the available legal sizes
(again, i32 and i64 in this case). Before, the implementation only
allowed specifying power-of-2-sized types (e.g. setAction({G_ADD, 0,
s128}, NarrowScalar).  A worse limitation was that if you'd wanted to
specify how to legalize all the sized types as allowed by the LLVM-IR
LangRef, i1 to i8388607, you'd have to call setAction 8388607-3 times
and probably would need a lot of memory to store all of these
specifications.

Instead, the legalization actions that need to change the size of the
type are specified now using a "SizeChangeStrategy".  For example:

   setLegalizeScalarToDifferentSizeStrategy(
       G_ADD, 0, widenToLargerAndNarrowToLargest);

This example indicates that for type sizes for which there is a larger
size that can be legalized towards, do it by Widening the size.
For example, G_ADD on s17 will be legalized by first doing WidenScalar
to make it s32, after which it's legal.
The "NarrowToLargest" indicates what to do if there is no larger size
that can be legalized towards. E.g. G_ADD on s92 will be legalized by
doing NarrowScalar to s64.

Another example, taken from the ARM backend is:
   for (unsigned Op : {G_SDIV, G_UDIV}) {
     setLegalizeScalarToDifferentSizeStrategy(Op, 0,
         widenToLargerTypesUnsupportedOtherwise);
     if (ST.hasDivideInARMMode())
       setAction({Op, s32}, Legal);
     else
       setAction({Op, s32}, Libcall);
   }

For this example, G_SDIV on s8, on a target without a divide
instruction, would be legalized by first doing action (WidenScalar,
s32), followed by (Libcall, s32).

The same principle is also followed for when the number of vector lanes
on vector data types need to be changed, e.g.:

   setAction({G_ADD, LLT::vector(8, 8)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(16, 8)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(4, 16)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(8, 16)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(2, 32)}, LegalizerInfo::Legal);
   setAction({G_ADD, LLT::vector(4, 32)}, LegalizerInfo::Legal);
   setLegalizeVectorElementToDifferentSizeStrategy(
       G_ADD, 0, widenToLargerTypesUnsupportedOtherwise);

As currently implemented here, vector types are legalized by first
making the vector element size legal, followed by then making the number
of lanes legal. The strategy to follow in the first step is set by a
call to setLegalizeVectorElementToDifferentSizeStrategy, see example
above.  The strategy followed in the second step
"moreToWiderTypesAndLessToWidest" (see code for its definition),
indicating that vectors are widened to more elements so they map to
natively supported vector widths, or when there isn't a legal wider
vector, split the vector to map it to the widest vector supported.

Therefore, for the above specification, some example legalizations are:
  * getAction({G_ADD, LLT::vector(3, 3)})
    returns {WidenScalar, LLT::vector(3, 8)}
  * getAction({G_ADD, LLT::vector(3, 8)})
    then returns {MoreElements, LLT::vector(8, 8)}
  * getAction({G_ADD, LLT::vector(20, 8)})
    returns {FewerElements, LLT::vector(16, 8)}


2. Key implementation aspects.

How to legalize a specific (operation, type index, size) tuple is
represented by mapping intervals of integers representing a range of
size types to an action to take, e.g.:

       setScalarAction({G_ADD, LLT:scalar(1)},
                       {{1, WidenScalar},  // bit sizes [ 1, 31[
                        {32, Legal},       // bit sizes [32, 33[
                        {33, WidenScalar}, // bit sizes [33, 64[
                        {64, Legal},       // bit sizes [64, 65[
                        {65, NarrowScalar} // bit sizes [65, +inf[
                       });

Please note that most of the code to do the actual lowering of
non-power-of-2 sized types is currently missing, this is just trying to
make it possible for targets to specify what is legal, and how non-legal
types should be legalized.  Probably quite a bit of further work is
needed in the actual legalizing and the other passes in GlobalISel to
support non-power-of-2 sized types.

I hope the documentation in LegalizerInfo.h and the examples provided in the
various {Target}LegalizerInfo.cpp and LegalizerInfoTest.cpp explains well
enough how this is meant to be used.

This drops the need for LLT::{half,double}...Size().


Differential Revision: https://reviews.llvm.org/D30529

llvm-svn: 317560
2017-11-07 10:34:34 +00:00
Quentin Colombet 7c114d3d70 [AArch64][LegalizerInfo] Mark s128 G_BITCAST legal
We used to mark all G_BITCAST of 128-bit legal but only for vector
types. Scalars of this size are just fine as well.

llvm-svn: 315945
2017-10-16 22:28:27 +00:00
Amara Emerson 1cd89ca669 [AArch64][GlobalISel] Make G_PHI of p0 types legal.
Differential Revision: https://reviews.llvm.org/D38621

llvm-svn: 315177
2017-10-08 15:29:11 +00:00
Daniel Sanders 83e23d1398 [globalisel] Add a G_BSWAP instruction and support bswap using it.
llvm-svn: 313633
2017-09-19 14:25:15 +00:00
Ahmed Bougacha 106dd035a8 [AArch64][GlobalISel] Select all fpexts.
Tablegen already can select these: mark them as legal, remove the
c++ code, and add tests for all types.

llvm-svn: 313074
2017-09-12 21:04:11 +00:00
Aditya Nandakumar 892979effc [GISel]: Implement widenScalar for Legalizing G_PHI
https://reviews.llvm.org/D37018

llvm-svn: 311763
2017-08-25 04:57:27 +00:00
Aditya Nandakumar efd8a84cd5 [GISEl]: Translate phi into G_PHI
G_PHI has the same semantics as PHI but also has types.
This lets us verify that the types in the G_PHI are consistent.
This also allows specifying legalization actions for G_PHIs.

https://reviews.llvm.org/D36990

llvm-svn: 311596
2017-08-23 20:45:48 +00:00
Quentin Colombet 250e050a50 [GlobalISel] Make GlobalISel a non-optional library.
With this change, the GlobalISel library gets always built. In
particular, this is not possible to opt GlobalISel out of the build
using the LLVM_BUILD_GLOBAL_ISEL variable any more.

llvm-svn: 309990
2017-08-03 21:52:25 +00:00
Aditya Nandakumar 02c602e18c [GISel]: Support Widening G_ICMP's destination operand.
Updated AArch64 to widen destination to s32.
https://reviews.llvm.org/D35737

Reviewed by Tim

llvm-svn: 309579
2017-07-31 17:00:16 +00:00
Daniel Sanders 40b66d646e [globalisel][tablegen] Enable the import of rules involving fma.
Summary:
G_FMA was recently added to GlobalISel which enables the import of rules
involving fma. Add the mapping to allow it.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

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

Differential Revision: https://reviews.llvm.org/D35130

llvm-svn: 308308
2017-07-18 14:10:07 +00:00
Aditya Nandakumar 1745121a45 [GISel]: Enhance the MachineIRBuilder API
Allows the MachineIRBuilder APIs to directly create registers (based on
LLT or TargetRegisterClass) as well as accept MachineInstrBuilders
and implicitly converts to register(with getOperand(0).getReg()).

Eg usage:
LLT s32 = LLT::scalar(32);
auto C32 = Builder.buildConstant(s32, 32);
auto Tmp = Builder.buildInstr(TargetOpcode::G_SUB, s32, C32,
OtherReg);
auto Tmp2 = Builder.buildInstr(Opcode, DstReg,
Builder.buildConstant(s32, 31)); ....

Only a few methods added for now.

Reviewed by Tim

llvm-svn: 307302
2017-07-06 19:40:07 +00:00