Commit Graph

61 Commits

Author SHA1 Message Date
Huihui Zhang f4f2706572 [ConstantFold][SVE] Fix constant folding for scalable vector compare instruction.
Summary:
Do not iterate on scalable vector. Also do not return constant scalable vector
from ConstantInt::get().
Fix result type by using getElementCount() instead of getNumElements().

Reviewers: sdesmalen, efriedma, apazos, huntergr, willlovett

Reviewed By: efriedma

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73753
2020-03-12 16:15:38 -07:00
Jay Foad 596446623b [AMDGPU][ConstantFolding] Fold llvm.amdgcn.cube* intrinsics
Summary:
This folds the following family of intrinsics:
llvm.amdgcn.cubeid (face id)
llvm.amdgcn.cubema (major axis)
llvm.amdgcn.cubesc (S coordinate)
llvm.amdgcn.cubetc (T coordinate)

Reviewers: nhaehnle, arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75187
2020-03-06 16:42:53 +00:00
Jay Foad 5900d3f2e9 [AMDGPU][ConstantFolding] Fold llvm.amdgcn.fract intrinsic
Reviewers: nhaehnle, arsenm, rampitec

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75179
2020-02-27 14:37:53 +00:00
Sanjay Patel d799190851 [ConstantFold] fold fsub -0.0, undef to undef rather than NaN
A question about this behavior came up on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2020-February/139003.html
...and as part of backend improvements in D73978, but this is an IR
change first because we already have fairly thorough tests in place
here.

We decided not to implement a more general change that would have
folded any FP binop with nearly arbitrary constant + undef operand
to undef because that is not theoretically correct (even if it is
practically correct).

Differential Revision: https://reviews.llvm.org/D74713
2020-02-21 08:03:19 -05:00
Sanjay Patel 7ddbf802cf [ConstantFold] add/move tests for FP with undef operand; NFC 2020-02-20 15:07:11 -05:00
Jay Foad b329d1b06e [AMDGPU][ConstantFolding] Fold llvm.amdgcn.fmul.legacy intrinsic
Reviewers: arsenm, rampitec, nhaehnle

Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, hiraditya, kerbowa, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74835
2020-02-19 16:01:30 +00:00
Huihui Zhang 5350a48931 [ConstantFold][SVE] Fix constant fold for FoldReinterpretLoadFromConstPtr.
Summary:
Bail out early for scalable vectors. As global variables are not expected
to be scalable.

Use explicit call of getFixedSize() to assert on places where scalable size
doesn't make sense.

Reviewers: sdesmalen, efriedma, apazos, huntergr, willlovett

Reviewed By: sdesmalen

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74424
2020-02-12 10:24:50 -08:00
Ehud Katz 2470d2988a [ConstantFolding] Fold calls to FP remainder function
With the fixed implementation of the "remainder" operation in
rG9d0956ebd471, we can now add support to folding calls to it.

Differential Revision: https://reviews.llvm.org/D69777
2020-02-12 13:21:18 +02:00
Huihui Zhang 88de9338f2 [ConstantFold][SVE] Fix constand fold for vector call.
Summary:
Do not iterate on scalable vectors.

Reviewers: sdesmalen, efriedma, apazos, huntergr, willlovett

Reviewed By: sdesmalen

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74419
2020-02-11 14:06:15 -08:00
Huihui Zhang 5389ca7a1f [ConstantFold][NFC] Move scalable vector unit tests under vscale.ll 2020-02-05 16:03:51 -08:00
Huihui Zhang 801857c59e [ConstantFold][SVE] Fix constant folding for bitcast.
Do not iterate on scalable vector type in BitCastConstantVector.
Continuation work of D70985, D71147.

Support for folding bitcast into splat value is kept in D74095, as
it depends on D71637.

Differential Revision: https://reviews.llvm.org/D71389
2020-02-05 15:39:57 -08:00
Christopher Tetreault b03f3fbd6a Reapply: [SVE] Fix bug in simplification of scalable vector instructions
This reverts commit a05441038a, reapplying
commit 31574d38ac
2020-02-05 10:00:09 -08:00
Reid Kleckner a05441038a Revert "[SVE] Fix bug in simplification of scalable vector instructions"
This reverts commit 31574d38ac.

The newly added shufflevector test does not pass locally on either of my
workstations.
2020-02-03 11:12:09 -08:00
Christopher Tetreault 31574d38ac [SVE] Fix bug in simplification of scalable vector instructions
Summary:
* Most of the simplifications in SimplifyShuffleVectorInst depend on the
concrete value of, or the length of the mask vector. For scalable
vectors, this cannot be known at compile time.
** for these tests, detect if the vector is scalable before attempting
the transformation
* The functions ShuffleVectorInst::getMaskValue and
ShuffleVectorInst::getShuffleMask access the value of the constant mask.
However, since the length of the mask is unknown at compile time, these
function do not work for scalable vectors. Add asserts to ensure that
the input mask is not scalable

Reviewers: efriedma, sdesmalen, apazos, chrisj, huihuiz

Reviewed By: efriedma

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73555
2020-02-03 10:15:56 -08:00
Huihui Zhang b0d25fff9b [ConstantFold][SVE][NFC] Add test for select instruction in scalable vector.
Side notes from D73669, no need to guard the iteration on vectors, as
it is explicitly looking for a ConstantVector/ConstantDataVector, which
is not expected to be scalable at the moment. So, add the test only.
2020-01-30 10:56:12 -08:00
Huihui Zhang 34e6552dcb [ConstantFold][SVE] Fix constant folding for scalable vector unary operations.
Summary:
Similar to issue D71445. Scalable vector should not be evaluated element by element.
Add support to handle scalable vector UndefValue.

Reviewers: sdesmalen, efriedma, apazos, huntergr, willlovett

Reviewed By: efriedma

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73678
2020-01-30 10:45:15 -08:00
Huihui Zhang d2e2fc450e [ConstantFold][SVE] Fix constant folding for scalable vector binary operations.
Summary:
Scalable vector should not be evaluated element by element.
Add support to handle scalable vector UndefValue.

Reviewers: sdesmalen, huntergr, spatel, lebedev.ri, apazos, efriedma, willlovett

Reviewed By: efriedma

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71445
2020-01-29 10:49:08 -08:00
Eli Friedman 7c69a03c56 [ConstantFold][SVE] Fix constant folding for shufflevector.
Don't try to fold away shuffles which can't be folded.  Fix creation of
shufflevector constant expressions.

Differential Revision: https://reviews.llvm.org/D71147
2019-12-09 15:31:50 -08:00
Huihui Zhang 381d3c5c45 [ConstantFold][SVE] Skip scalable vectors in ConstantFoldInsertElementInstruction.
Summary:
Should not constant fold insertelement instruction for scalable vector type.

Reviewers: huntergr, sdesmalen, spatel, levedev.ri, apazos, efriedma, willlovett

Reviewed By: efriedma, spatel

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D70985
2019-12-05 19:43:19 -08:00
Sanjay Patel 8d20dd0b06 [ConstFolding] move tests for copysign; NFC
InstCombine doesn't have any transforms for copysign currently.
2019-11-26 16:54:46 -05:00
Florian Hahn 8eeabbaf5d [ConstantFold] Handle identity folds at top of ConstantFoldBinaryInst
Currently we miss folds with undef and identity values for binary ops
that do not fold to undef in general.

We can generalize the identity simplifications and do them before
checking for undef in particular.

Alive checks:
 * OR - https://rise4fun.com/Alive/8OsK
 * AND - https://rise4fun.com/Alive/e3tE

This will also allow us to remove some now redundant cases throughout
the function, but I would like to do this as follow-up. That should make
tracking down potential issues easier.

Reviewers: spatel, RKSimon, lebedev.ri

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D70169
2019-11-17 21:30:14 +00:00
Florian Hahn 28c183859a [ConstantFold] Add some tests for binops with constants and undefs.
Precommit tests for D70169.
2019-11-17 21:10:45 +00:00
Jay Foad 843c0adf0f [ConstantFold] Fold extractelement of getelementptr
Summary:
Getelementptr has vector type if any of its operands are vectors
(the scalar operands being implicitly broadcast to all vector elements).
Extractelement applied to a vector getelementptr can be folded by
applying the extractelement in turn to all of the vector operands.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69379
2019-10-28 18:32:39 +00:00
Evandro Menezes 22cb3d2e58 [ConstantFolding] Fold constant calls to log2()
Somehow, folding calls to `log2()` with a constant was missing.

Differential revision: https://reviews.llvm.org/D67300

llvm-svn: 373262
2019-09-30 20:53:23 +00:00
Evandro Menezes 08df6e64d5 [ConstantFolding] Expand folding of some library functions
Expanding the folding of `nearbyint()`, `rint()` and `trunc()` to library
functions, in addition to the current support for intrinsics.

Differential revision: https://reviews.llvm.org/D67468

llvm-svn: 371774
2019-09-12 21:23:22 +00:00
Evandro Menezes 88a98ea3f7 [ConstantFolding] Add new test cases for transcendentals (NFC)
llvm-svn: 371246
2019-09-06 19:41:49 +00:00
Peter Collingbourne ddccb494ee Fix pointer width in test from r366754.
llvm-svn: 366764
2019-07-22 23:32:41 +00:00
Peter Collingbourne 710605c085 Analysis: Don't look through aliases when simplifying GEPs.
It is not safe in general to replace an alias in a GEP with its aliasee
if the alias can be replaced with another definition (i.e. via strong/weak
resolution (linkonce_odr) or via symbol interposition (default visibility
in ELF)) while the aliasee cannot. An example of how this can go wrong is
in the included test case.

I was concerned that this might be a load-bearing misoptimization (it's
possible for us to use aliases to share vtables between base and derived
classes, and on Windows, vtable symbols will always be aliases in RTTI
mode, so this change could theoretically inhibit trivial devirtualization
in some cases), so I built Chromium for Linux and Windows with and without
this change. The file sizes of the resulting binaries were identical, so it
doesn't look like this is going to be a problem.

Differential Revision: https://reviews.llvm.org/D65118

llvm-svn: 366754
2019-07-22 22:13:46 +00:00
Bjorn Pettersson 16ff5fea87 [ConstantFolding] Add constant folding for smul.fix and smul.fix.sat
Summary:
This patch teaches ConstantFolding to constant fold
both scalar and vector variants of llvm.smul.fix and
llvm.smul.fix.sat.

As described in the LangRef rounding is unspecified for
these instrinsics. If the result cannot be represented
exactly the default behavior in ConstantFolding is to
round down towards negative infinity. If a target has a
preferred rounding that is different some kind of target
hook would be needed (same strategy as used by the
SelectionDAG legalizer).

Reviewers: nikic, leonardchan, RKSimon

Reviewed By: leonardchan

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D63385

llvm-svn: 363811
2019-06-19 14:28:03 +00:00
Cameron McInally c3167696bc Add FNeg support to InstructionSimplify
Differential Revision: https://reviews.llvm.org/D61573

llvm-svn: 360053
2019-05-06 16:05:10 +00:00
Cameron McInally 1c34db85e5 Precommit an FNeg InstructionSimplify test.
llvm-svn: 359990
2019-05-05 18:22:09 +00:00
Cameron McInally 1d0c845d9d Add FNeg IR constant folding support
llvm-svn: 359982
2019-05-05 16:07:09 +00:00
Nikita Popov 9f6e9cf71b [ConstantFolding] Fold undef for integer intrinsics
This fixes https://bugs.llvm.org/show_bug.cgi?id=40110.

This implements handling of undef operands for integer intrinsics in
ConstantFolding, in particular for the bitcounting intrinsics (ctpop,
cttz, ctlz), the with.overflow intrinsics, the saturating math
intrinsics and the funnel shift intrinsics.

The undef behavior follows what InstSimplify does for the general cas
e of non-constant operands. For the bitcount intrinsics (where
InstSimplify doesn't do undef handling -- there cannot be a combination
of an undef + non-constant operand) I'm using a 0 result if the intrinsic
is defined for zero and undef otherwise.

Differential Revision: https://reviews.llvm.org/D55950

llvm-svn: 350971
2019-01-11 21:18:00 +00:00
Ranjeet Singh 107dd2565c Revert patches 348835 and 348571 because they're
causing code size performance regressions.

llvm-svn: 350402
2019-01-04 16:39:10 +00:00
Nikita Popov f17421e595 [ConstantFolding] Consolidate and extend bitcount intrinsic tests; NFC
Move constant folding tests into ConstantFolding/bitcount.ll and drop
various tests in other places. Add coverage for undefs.

llvm-svn: 349806
2018-12-20 19:46:52 +00:00
Nikita Popov 41a7b109c3 [ConstantFolding] Add tests for funnel shifts with undef operands; NFC
llvm-svn: 349803
2018-12-20 19:46:39 +00:00
Nikita Popov 2d6fa5d6b4 [ConstantFolding] Add tests for sat add/sub with undefs; NFC
llvm-svn: 349802
2018-12-20 19:46:35 +00:00
Nikita Popov f7ef6d6461 [ConstantFolding] Split up saturating add/sub tests; NFC
Split each test into a separate function.

llvm-svn: 349801
2018-12-20 19:46:30 +00:00
Ranjeet Singh ce24c878d9 Cleanup test case by removing unused attribute dso_local
Attribute 'dso_local' generated in bitcode from compiling
original C file but isn't needed.

Differential Revision: https://reviews.llvm.org/D55521

llvm-svn: 348835
2018-12-11 09:32:49 +00:00
Ranjeet Singh 7a7132603b [IR] Don't assume all functions are 4 byte aligned
In some cases different alignments for function might be used to save
space e.g. thumb mode with -Oz will try to use 2 byte function
alignment. Similar patch that fixed this in other areas exists here
https://reviews.llvm.org/D46110

This was approved previously https://reviews.llvm.org/D55115 (r348215)
but when committed it caused failures on the sanitizer buildbots when
building llvm with clang (containing this patch). This is now fixed
because I've added a check to see if getting the parent module returns
null if it does then set the alignment to 0.

Differential Revision: https://reviews.llvm.org/D55115

llvm-svn: 348571
2018-12-07 08:34:59 +00:00
Ranjeet Singh b393a516fb Reverting r348215
Causing failures on ubsan buildbot boxes.

llvm-svn: 348230
2018-12-04 02:03:53 +00:00
Ranjeet Singh f5d1b6413f [IR] Don't assume all functions are 4 byte aligned
In some cases different alignments for function might be used to save
space e.g. thumb mode with -Oz will try to use 2 byte function
alignment. Similar patch that fixed this in other areas exists here
https://reviews.llvm.org/D46110

Differential Revision: https://reviews.llvm.org/D55115

llvm-svn: 348215
2018-12-04 00:01:23 +00:00
Sanjay Patel efc3d1dfaa [ConstantFolding] Add support for saturating add/sub
Support saturating add/sub in constant folding, based on the APInt methods introduced in D54332.

Patch by: @nikic (Nikita Popov)

Differential Revision: https://reviews.llvm.org/D54531

llvm-svn: 347328
2018-11-20 17:05:55 +00:00
Thomas Lively fa54e56d84 [ConstantFolding] Constant fold minimum and maximum intrinsics
Summary: Depends on D52764

Reviewers: aheejin, dschuff

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52765

llvm-svn: 344796
2018-10-19 18:15:32 +00:00
Peter Collingbourne c7d281905b Prevent Constant Folding From Optimizing inrange GEP
This patch does the following things:

1. update SymbolicallyEvaluateGEP so that it bails out if it cannot preserve inrange arribute;
2. update llvm/test/Analysis/ConstantFolding/gep.ll to remove UB in it;
3. remove inaccurate comment above ConstantFoldInstOperandsImpl in llvm/lib/Analysis/ConstantFolding.cpp;
4. add a new regression test that makes sure that no optimizations change an inrange GEP in an unexpected way.

Patch by Zhaomo Yang!

Differential Revision: https://reviews.llvm.org/D51698

llvm-svn: 341888
2018-09-11 01:53:36 +00:00
Sanjay Patel 7a05641fa8 [InstCombine] remove unnecessary shuffle undef folding
Add a test for constant folding to show that 
(shuffle undef, undef, mask)
should already be handled via instsimplify.

llvm-svn: 340926
2018-08-29 13:24:34 +00:00
Sanjay Patel 3ce999fa41 [ConstantFolding] improve folding of binops with vector undef operand
A non-undef operand may still have undef constant elements, 
so we should always propagate the vector results per-lane.

llvm-svn: 340194
2018-08-20 18:19:02 +00:00
Sanjay Patel 7ff7bd9b3c [ConstantFolding] add tests for binops on vectors with undef elements; NFC
llvm-svn: 340190
2018-08-20 17:31:34 +00:00
Sanjay Patel 411b86081e [ConstantFolding] add simplifications for funnel shift intrinsics
This is another step towards being able to canonicalize to the funnel shift 
intrinsics in IR (see D49242 for the initial patch). 
We should not have any loss of simplification power in IR between these and 
the equivalent IR constructs.

Differential Revision: https://reviews.llvm.org/D50848

llvm-svn: 340022
2018-08-17 13:23:44 +00:00
Sanjay Patel 0ea8d8b951 [ConstantFolding] add tests for funnel shift intrinsics; NFC
No functionality for this yet.

llvm-svn: 339889
2018-08-16 16:10:42 +00:00