Commit Graph

7993 Commits

Author SHA1 Message Date
Florian Hahn 5947c17fd4 [SCEVExp] Advance found insertion point until we find a non-dbg instruction.
This avoids creating unnecessary casts if the IP used to be a dbg info
intrinsic. Fixes PR37727.

Reviewers: vsk, aprantl, sanjoy, efriedma

Reviewed By: vsk, efriedma

Differential Revision: https://reviews.llvm.org/D47874

llvm-svn: 335513
2018-06-25 19:17:29 +00:00
Sanjay Patel 1e911fa746 [InstSimplify] fold div/rem of zexted bool
I was looking at an unrelated fold and noticed that
we don't have this simplification (because the other
fold would break existing tests).

Name: zext udiv
  %z = zext i1 %x to i32
  %r = udiv i32 %y, %z
=>
  %r = %y

Name: zext urem
  %z = zext i1 %x to i32
  %r = urem i32 %y, %z
=>
  %r = 0

Name: zext sdiv
  %z = zext i1 %x to i32
  %r = sdiv i32 %y, %z
=>
  %r = %y

Name: zext srem
  %z = zext i1 %x to i32
  %r = srem i32 %y, %z
=>
  %r = 0

https://rise4fun.com/Alive/LZ9

llvm-svn: 335512
2018-06-25 18:51:21 +00:00
Alexander Richardson 85e200e934 Add Triple::isMIPS()/isMIPS32()/isMIPS64(). NFC
There are quite a few if statements that enumerate all these cases. It gets
even worse in our fork of LLVM where we also have a Triple::cheri (which
is mips64 + CHERI instructions) and we had to update all if statements that
check for Triple::mips64 to also handle Triple::cheri. This patch helps to
reduce our diff to upstream and should also make some checks more readable.

Reviewed By: atanasyan

Differential Revision: https://reviews.llvm.org/D48548

llvm-svn: 335493
2018-06-25 16:49:20 +00:00
David Green 8699492304 [DA] Delinearise AddRecs if we can prove they don't wrap
We can prove that some delinearized subscripts do not wrap around to become
negative by the fact that they are from inbound geps of load/store locations.
This helps improve the delinearisation in cases where we can't prove that they
are non-negative from SCEV alone.

Differential Revision: https://reviews.llvm.org/D48481

llvm-svn: 335481
2018-06-25 15:13:26 +00:00
George Burgess IV 97ec62455d [MSSA] Add domination number verifier; NFC
It's easy for domination numbers to get out-of-date, and this is no more
costly than any of the other verifiers we already have, so it seems nice
to have.

A stage3 build with this Works On My Machine, so this hasn't caught any
bugs... yet. :)

llvm-svn: 335444
2018-06-25 05:30:36 +00:00
George Burgess IV 2cbf9730b0 [MSSA] Remove incorrect comment + `auto`ify dyn_cast results; NFC
llvm-svn: 335399
2018-06-22 22:34:07 +00:00
Chandler Carruth fe70b29cf7 [LegacyPM] Fix PR37888 by teaching the legacy loop pass manager how to
clear out deleted loops from the current queue beyond just the current
loop.

This is important because SimpleLoopUnswitch will now enqueue the same
loop to be re-processed. When it does this with the legacy PM, we don't
have a way of canceling the rest of the pipeline and so we can end up
deleting the loop before we reprocess it. =/

This change also makes it easy to support deleting other loops in the
queue to process, although I don't have any use cases for that.

Differential Revision: https://reviews.llvm.org/D48470

llvm-svn: 335317
2018-06-22 02:43:41 +00:00
Tim Shen 63f244c4f4 [SCEV] Re-apply r335197 (with Polly fixes).
Summary:
This initiates a discussion on changing Polly accordingly while re-applying r335197 (D48338).

I have never worked on Polly. The proposed change to param_div_div_div_2.ll is not educated, but just patterns that match the output.

All LLVM files are already reviewed in D48338.

Reviewers: jdoerfert, bollu, efriedma

Subscribers: jlebar, sanjoy, hiraditya, llvm-commits, bixia

Differential Revision: https://reviews.llvm.org/D48453

llvm-svn: 335292
2018-06-21 21:29:54 +00:00
David Green d143c65de3 [DA] Enable -da-delinearize by default
This enables da-delinearize in Dependence Analysis for delinearizing array
accesses into multiple dimensions. This can help to increase the power of
Dependence analysis on multi-dimensional arrays and prevent having to fall
back to the slower and less accurate MIV tests. It adds static checks on the
bounds of the arrays to ensure that one dimension doesn't overflow into
another, and brings our code in line with our tests.

Differential Revision: https://reviews.llvm.org/D45872

llvm-svn: 335217
2018-06-21 11:53:16 +00:00
Tim Shen 433b9761ce Revert "[SCEV] Improve zext(A /u B) and zext(A % B)"
This reverts commit r335197, as some bots are not happy.

llvm-svn: 335198
2018-06-21 02:15:32 +00:00
Tim Shen 5af61e0a28 [SCEV] Improve zext(A /u B) and zext(A % B)
Summary:
Try to match udiv and urem patterns, and sink zext down to the leaves.

I'm not entirely sure why some unrelated tests change, but the added <nsw>s seem right.

Reviewers: sanjoy

Subscribers: jlebar, hiraditya, bixia, llvm-commits

Differential Revision: https://reviews.llvm.org/D48338

llvm-svn: 335197
2018-06-21 01:49:07 +00:00
Alina Sbirlea 201d02c75c [MemorySSA] Verify Phi incoming blocks are block predecessors.
Summary: Make the MemorySSA verify also check that all Phi incoming blocks are block predecessors.

Reviewers: george.burgess.iv

Subscribers: sanjoy, jlebar, Prazek, llvm-commits

Differential Revision: https://reviews.llvm.org/D48333

llvm-svn: 335174
2018-06-20 21:06:13 +00:00
Sanjay Patel 0c57de4c21 [InstSimplify] Fix missed optimization in simplifyUnsignedRangeCheck()
For both operands are unsigned, the following optimizations are valid, and missing:

   1. X > Y && X != 0 --> X > Y
   2. X > Y || X != 0 --> X != 0
   3. X <= Y || X != 0 --> true
   4. X <= Y || X == 0 --> X <= Y
   5. X > Y && X == 0 --> false

unsigned foo(unsigned x, unsigned y) { return x > y && x != 0; }
should fold to x > y, but I found we haven't done it right now.
besides, unsigned foo(unsigned x, unsigned y) { return x < y && y != 0; }
Has been folded to x < y, so there may be a bug.

Patch by: Li Jia He!

Differential Revision: https://reviews.llvm.org/D47922

llvm-svn: 335129
2018-06-20 14:22:49 +00:00
Sanjay Patel 2ca3360b11 [IR] move shuffle mask queries from TTI to ShuffleVectorInst
The optimizer is getting smarter (eg, D47986) about differentiating shuffles 
based on its mask values, so we should make queries on the mask constant 
operand generally available to avoid code duplication.

We'll probably use this soon in the vectorizers and instcombine (D48023 and 
https://bugs.llvm.org/show_bug.cgi?id=37806).

We might clean up TTI a bit more once all of its current 'SK_*' options are 
covered.

Differential Revision: https://reviews.llvm.org/D48236

llvm-svn: 335067
2018-06-19 18:44:00 +00:00
Sanjoy Das 6e9b355cc9 Revert "[SCEV] Add nuw/nsw to mul ops in StrengthenNoWrapFlags"
This reverts r334428.  It incorrectly marks some multiplications as nuw.  Tim
Shen is working on a proper fix.

Original commit message:

[SCEV] Add nuw/nsw to mul ops in StrengthenNoWrapFlags where safe.

Summary:
Previously we would add them for adds, but not multiplies.

llvm-svn: 335016
2018-06-19 04:09:44 +00:00
Benjamin Kramer 1193bbf6b7 Fix namespaces. No functionality change.
llvm-svn: 334890
2018-06-16 13:37:52 +00:00
Justin Lebar 3f5490af21 Revert "[SCEV] Use LLVM_MARK_AS_BITMASK_ENUM in SCEV." -- breaks MSVC builds.
This reverts D48237.

llvm-svn: 334878
2018-06-16 00:14:10 +00:00
Justin Lebar 018c3790f9 Revert "[SCEV] Simplify some flags expressions." -- dependent revision breaks MSVC builds.
This reverts D48238.

llvm-svn: 334877
2018-06-16 00:13:57 +00:00
Justin Lebar af30bb1c90 [SCEV] Simplify some flags expressions.
Summary:
Sending for presubmit review out of an abundance of caution; it would be
bad to mess this up.

Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D48238

llvm-svn: 334875
2018-06-15 23:52:11 +00:00
Justin Lebar 6cb702d00d [SCEV] Use LLVM_MARK_AS_BITMASK_ENUM in SCEV.
Summary:
Obviates the need for mask/clear/setFlags helpers.

There are some expressions here which can be simplified, but to keep
this easy to review, I have not simplified them in this patch.

No functional change.

Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D48237

llvm-svn: 334874
2018-06-15 23:51:57 +00:00
Benjamin Kramer 7f68a309ac [BPI] Remove unnecessary std::list
vector is sufficient here. No functionality change intended.

llvm-svn: 334865
2018-06-15 21:06:43 +00:00
George Burgess IV aa283d80fe [MSSA] Print more optimization information
In particular, when asked to print a MemoryAccess, we'll now print where
defs are optimized to, and we'll print optimized access types.

This patch also introduces an operator<< to make printing AliasResults
easier.

Patch by Juneyoung Lee!

Differential Revision: https://reviews.llvm.org/D47860

llvm-svn: 334760
2018-06-14 19:55:53 +00:00
Justin Lebar bdb0a58c91 [SCEV] Fix a variable name, NFC.
llvm-svn: 334738
2018-06-14 17:14:01 +00:00
Justin Lebar fe455464eb [SCEV] Simplify zext/trunc idiom that appears when handling bitmasks.
Summary:
Specifically, we transform

  zext(2^K * (trunc X to iN)) to iM ->
  2^K * (zext(trunc X to i{N-K}) to iM)<nuw>

This is helpful because pulling the 2^K out of the zext allows further
optimizations.

Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits, timshen

Differential Revision: https://reviews.llvm.org/D48158

llvm-svn: 334737
2018-06-14 17:13:48 +00:00
Justin Lebar b326904dba [SCEV] Simplify trunc-of-add/mul to add/mul-of-trunc under more circumstances.
Summary:
Previously we would do this simplification only if it did not introduce
any new truncs (excepting new truncs which replace other cast ops).

This change weakens this condition: If the number of truncs stays the
same, but we're able to transform trunc(X + Y) to X + trunc(Y), that's
still simpler, and it may open up additional transformations.

While we're here, also clean up some duplicated code.

Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D48160

llvm-svn: 334736
2018-06-14 17:13:35 +00:00
Justin Lebar 62a0747926 [SCEV] Fix indentation and combine two if statements in getMulExpr, NFC.
llvm-svn: 334735
2018-06-14 17:13:22 +00:00
Simon Pilgrim c0d53aba7b [CostModel] Cleanup isSingleSourceVectorMask to match other shuffle matchers. NFCI.
llvm-svn: 334699
2018-06-14 09:48:19 +00:00
Simon Pilgrim 32702cc86a [CostModel] Recognise REVERSE shuffle mask if the elements come from the second src
llvm-svn: 334698
2018-06-14 09:35:00 +00:00
Simon Pilgrim 54a138a0c5 [CostModel] Recognise BROADCAST shuffle mask if the elements come from the second src
llvm-svn: 334620
2018-06-13 16:52:02 +00:00
Simon Pilgrim e39fa6cbbb [CostModel] Replace ShuffleKind::SK_Alternate with ShuffleKind::SK_Select (PR33744)
As discussed on PR33744, this patch relaxes ShuffleKind::SK_Alternate which requires shuffle masks to only match an alternating pattern from its 2 sources:

e.g. v4f32: <0,5,2,7> or <4,1,6,3>

This seems far too restrictive as most SIMD hardware which will implement it using a general blend/bit-select instruction, so replaces it with SK_Select, permitting elements from either source as long as they are inline:

e.g. v4f32: <0,5,2,7>, <4,1,6,3>, <0,1,6,7>, <4,1,2,3> etc.

This initial patch just updates the name and cost model shuffle mask analysis, later patch reviews will update SLP to better utilise this - it still limits itself to SK_Alternate style patterns.

Differential Revision: https://reviews.llvm.org/D47985

llvm-svn: 334513
2018-06-12 16:12:29 +00:00
Simon Pilgrim 51ef8dabcd Fix signed/unsigned warning. NFCI.
llvm-svn: 334509
2018-06-12 15:14:34 +00:00
Simon Pilgrim 0783921987 [CostModel] Treat Identity shuffle masks as zero cost
As discussed on D47985, identity shuffle masks should probably be free.

I've limited this to the case where the input and output types all match - but we could probably accept all cases.

Differential Revision: https://reviews.llvm.org/D47986

llvm-svn: 334506
2018-06-12 14:47:13 +00:00
Justin Lebar 4da41c13a5 [SCEV] Add transform zext((A * B * ...)<nuw>) --> (zext(A) * zext(B) * ...)<nuw>.
Reviewers: sanjoy

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D48041

llvm-svn: 334429
2018-06-11 18:57:58 +00:00
Justin Lebar aa4fec94d8 [SCEV] Add nuw/nsw to mul ops in StrengthenNoWrapFlags where safe.
Summary:
Previously we would add them for adds, but not multiplies.

Reviewers: sanjoy

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D48038

llvm-svn: 334428
2018-06-11 18:57:42 +00:00
Justin Lebar 7b4656c1d3 Fix indentation in ScalarEvolution.cpp.
Whitespace-only change.  (clang-formatted the whole block.)

llvm-svn: 334427
2018-06-11 18:57:27 +00:00
Tim Shen cc63761720 [SCEV] Canonicalize "A /u C1 /u C2" to "A /u (C1*C2)".
Summary: FWIW InstCombine already folds this. Also avoid the case where C1*C2 overflows.

Reviewers: sunfish, sanjoy

Subscribers: hiraditya, bixia, llvm-commits

Differential Revision: https://reviews.llvm.org/D47965

llvm-svn: 334425
2018-06-11 18:44:58 +00:00
Krzysztof Parzyszek b10ea39270 [SCEV] Look through zero-extends in howFarToZero
An expression like
  (zext i2 {(trunc i32 (1 + %B) to i2),+,1}<%while.body> to i32)
will become zero exactly when the nested value becomes zero in its type.
Strip injective operations from the input value in howFarToZero to make
the value simpler.

Differential Revision: https://reviews.llvm.org/D47951

llvm-svn: 334318
2018-06-08 20:43:07 +00:00
Roman Lebedev f87321a2dc [NFC][InstSimplify] SimplifyAddInst(): coding style: variable names.
llvm-svn: 334299
2018-06-08 15:44:53 +00:00
Roman Lebedev b060ce45ca [InstSimplify] add nuw %x, -1 -> -1 fold.
Summary:
`%ret = add nuw i8 %x, C`
From [[ https://llvm.org/docs/LangRef.html#add-instruction | langref ]]:
    nuw and nsw stand for “No Unsigned Wrap” and “No Signed Wrap”,
    respectively. If the nuw and/or nsw keywords are present,
    the result value of the add is a poison value if unsigned
    and/or signed overflow, respectively, occurs.

So if `C` is `-1`, `%x` can only be `0`, and the result is always `-1`.

I'm not sure we want to use `KnownBits`/`LVI` here, because there is
exactly one possible value (all bits set, `-1`), so some other pass
should take care of replacing the known-all-ones with constant `-1`.

The `test/Transforms/InstCombine/set-lowbits-mask-canonicalize.ll` change *is* confusing.
What happening is, before this: (omitting `nuw` for simplicity)
1. First, InstCombine D47428/rL334127 folds `shl i32 1, %NBits`) to `shl nuw i32 -1, %NBits`
2. Then, InstSimplify D47883/rL334222 folds `shl nuw i32 -1, %NBits` to `-1`,
3. `-1` is inverted to `0`.
But now:
1. *This* InstSimplify fold `%ret = add nuw i32 %setbit, -1` -> `-1` happens first,
   before InstCombine D47428/rL334127 fold could happen.
Thus we now end up with the opposite constant,
and it is all good: https://rise4fun.com/Alive/OA9

https://rise4fun.com/Alive/sldC
Was mentioned in D47428 review.
Follow-up for D47883.

Reviewers: spatel, craig.topper

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47908

llvm-svn: 334298
2018-06-08 15:44:47 +00:00
Artur Pilipenko 4d063e7bb1 [BPI] Apply invoke heuristic before loop branch heuristic
Currently the loop branch heuristic is applied before the invoke heuristic which makes us overestimate the probability of the unwind destination of invokes inside loops. This in turn makes us grossly underestimate the frequencies of loops with invokes.

Reviewed By: skatkov, vsk

Differential Revision: https://reviews.llvm.org/D47371

llvm-svn: 334285
2018-06-08 13:03:21 +00:00
Roman Lebedev 2683802ba0 [InstSimplify] shl nuw C, %x -> C iff signbit is set on C.
Summary:
`%r = shl nuw i8 C, %x`

As per langref:
```
If the nuw keyword is present, then the shift produces
a poison value if it shifts out any non-zero bits.
```
Thus, if the sign bit is set on `C`, then `%x` can only be `0`,
which means that `%r` can only be `C`.
Or in other words, set sign bit means that the signed value
is negative, so the constant is `<= 0`.

https://rise4fun.com/Alive/WMk
https://rise4fun.com/Alive/udv

Was mentioned in D47428 review.

We already handle the `0` constant, https://godbolt.org/g/UZq1sJ, so this only handles negative constants.

Could use computeKnownBits() / LazyValueInfo,
but the cost-benefit analysis (https://reviews.llvm.org/D47891)
suggests it isn't worth it.

Reviewers: spatel, craig.topper

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47883

llvm-svn: 334222
2018-06-07 20:03:45 +00:00
Sanjay Patel 4b1205b40f [TargetLibraryInfo] add mappings from LLVM sin/cos intrinsics to SVML calls
These weren't included in D19544 - probably just an oversight.
D40044 made it more likely that we'll have LLVM math intrinsics rather 
than libcalls, so this bug was more easily exposed.
As the tests/code show, we already have the complete mappings for pow/exp/log.

I don't have any experience with SVML, so I don't know if anything else is 
missing. It's also not clear to me that we should be doing this transform in 
IR rather than DAG/isel, but that's a separate issue.

Differential Revision: https://reviews.llvm.org/D47610

llvm-svn: 334211
2018-06-07 18:21:24 +00:00
Teresa Johnson 4ffc3e7834 [ThinLTO] Rename index IsAnalysis flag to HaveGVs (NFC)
With the upcoming patch to add summary parsing support, IsAnalysis would
be true in contexts where we are not performing module summary analysis.
Rename to the more specific and approprate HaveGVs, which is essentially
what this flag is indicating.

llvm-svn: 334140
2018-06-06 22:22:01 +00:00
John Brawn c5a6392be3 [ValueTracking] Match select abs pattern when there's an sext involved
When checking a select to see if it matches an abs, allow the true/false values
to be a sign-extension of the comparison value instead of requiring that they're
directly the comparison value, as all the comparison cares about is the sign of
the value.

This fixes a regression due to r333702, where we were no longer generating ctlz
due to isKnownNonNegative failing to match such a pattern.

Differential Revision: https://reviews.llvm.org/D47631

llvm-svn: 333927
2018-06-04 16:53:57 +00:00
David Green 2911b3a07a [DA] Fix direction vectors for weakZeroSrcSIV
Both weakZeroSrcSIV and weakZeroDstSIV are currently giving the same
direction vectors. Fix weakZeroSrcSIVtest by flipping the directions
it gives.

Differential Revision: https://reviews.llvm.org/D46678

llvm-svn: 333658
2018-05-31 14:55:29 +00:00
Karl-Johan Karlsson ebaaa2ddae [ValueTracking] Fix endless recursion in isKnownNonZero()
Summary:
The isKnownNonZero() function have checks that abort the recursion when
it reaches the specified max depth. However one of the recursive calls
was placed before the max depth check was done, resulting in a endless
recursion that eventually triggered a segmentation fault.

Fixed the problem by moving the max depth check above the first
recursive call.

Reviewers: Prazek, nlopes, spatel, craig.topper, hfinkel

Reviewed By: hfinkel

Subscribers: hfinkel, bjope, llvm-commits

Differential Revision: https://reviews.llvm.org/D47531

llvm-svn: 333557
2018-05-30 15:56:46 +00:00
Daniel Neilson 6b23fb764e [AliasSet] Teach the alias set how to handle atomic memcpy/memmove/memset
Summary:
The atomic variants of the memcpy/memmove/memset intrinsics can be treated
the same was as the regular forms, with respect to aliasing. Update the
AliasSetTracker to treat the atomic forms the same was as the regular forms.

llvm-svn: 333551
2018-05-30 14:43:39 +00:00
Daniel Neilson 3a6c50f4e0 [BasicAA] Teach the analysis about atomic memcpy
Summary:
A simple change to derive mod/ref info from the atomic memcpy
intrinsic in the same way as from the regular memcpy intrinsic.

llvm-svn: 333454
2018-05-29 19:23:50 +00:00
George Burgess IV 45f263dd90 [MemorySSA] Reflow comments + clean up control flow; NFC
Style guide says `else`s after returns are iffy, and I agree. I also
don't know what broke the comments here and in CFLAA, but *shrug*.

llvm-svn: 333332
2018-05-26 02:28:55 +00:00
George Burgess IV e81681805c [CFLAA] Reflow comments; NFC
llvm-svn: 333330
2018-05-26 02:17:43 +00:00