Sinking of unordered atomic load into loop must be disallowed because it turns
a single load into multiple loads. The relevant section of the documentation
is: http://llvm.org/docs/Atomics.html#unordered, specifically the Notes for
Optimizers section. Here is the full text of this section:
> Notes for optimizers
> In terms of the optimizer, this **prohibits any transformation that
> transforms a single load into multiple loads**, transforms a store into
> multiple stores, narrows a store, or stores a value which would not be
> stored otherwise. Some examples of unsafe optimizations are narrowing
> an assignment into a bitfield, rematerializing a load, and turning loads
> and stores into a memcpy call. Reordering unordered operations is safe,
> though, and optimizers should take advantage of that because unordered
> operations are common in languages that need them.
Patch by Daniil Suchkov!
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D38392
llvm-svn: 315438
IRCE should not apply when the safe iteration range is proved to be empty.
In this case we do unneeded job creating pre/post loops and then never
go to the main loop.
This patch makes IRCE not apply to empty safe ranges, adds test for this
situation and also modifies one of existing tests where it used to happen
slightly.
Reviewed By: anna
Differential Revision: https://reviews.llvm.org/D38577
llvm-svn: 315437
Summary: In the current implementation, we only have accurate profile count for standalone symbols. For inlined functions, we do not have entry count data because it's not available in LBR. In this patch, we use the first instruction's frequency to estimiate the function's entry count, especially for inlined functions. This may be inaccurate due to debug info in optimized code. However, this is a better estimate than the static 80/20 estimation we have in the current implementation.
Reviewers: tejohnson, davidxl
Reviewed By: tejohnson
Subscribers: sanjoy, llvm-commits, aprantl
Differential Revision: https://reviews.llvm.org/D38478
llvm-svn: 315369
Eliminate inttype phi with inttoptr/ptrtoint.
This version fixed a bug in finding the matching
phi -- the order of the incoming blocks may be
different (triggered in self build on Windows).
A new test case is added.
llvm-svn: 315272
There's at least one bug here - this code can fail with vector types (PR34856).
It's also being called for FREM; I'm still trying to understand how that is valid.
llvm-svn: 315127
This appears to be miscompiling Clang, as shown on two Windows bootstrap
bots:
http://lab.llvm.org:8011/builders/clang-x86-windows-msvc2015/builds/7611http://lab.llvm.org:8011/builders/clang-x64-ninja-win7/builds/6870
Nothing else is in the blame list. Both emit errors on this valid code
in the Windows ucrt headers:
C:\...\ucrt\malloc.h:95:32: error: invalid operands to binary expression ('char *' and 'int')
_Ptr = (char*)_Ptr + _ALLOCA_S_MARKER_SIZE;
~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~
I am attempting to reproduce this now.
This reverts r315044
llvm-svn: 315108
Summary: stripPointerCast is not reliably returning the value that's being type-casted. Instead it may look further at function attributes to further propagate the value. Instead of relying on stripPOintercast, the more reliable solution is to directly use the pointer to the promoted direct call.
Reviewers: tejohnson, davidxl
Reviewed By: tejohnson
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D38603
llvm-svn: 315077
This is a vestige from the GCC-3 days, which disables IPO passes
when set. I don't think anybody actually uses it as there are
several IPO passes which still run with this flag set and
nobody complained/noticed. This reduces the delta between
current and new pass manager and allows us to easily review
the difference when we decide to flip the switch (or audit
which passes should run, FWIW).
llvm-svn: 315043
Summary:
If the extracted region has multiple exported data flows toward the same BB which is not included in the region, correct resotre instructions and PHI nodes won't be generated inside the exitStub. The solution is simply put the restore instructions right after the definition of output values instead of putting in exitStub.
Unittest for this bug is included.
Author: myhsu
Reviewers: chandlerc, davide, lattner, silvas, davidxl, wmi, kuhar
Subscribers: dberlin, kuhar, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D37902
llvm-svn: 315041
It is possible for two modules to define the same set of external
symbols without causing a duplicate symbol error at link time,
as long as each of the symbols is a comdat member. So we cannot
use them as part of a unique id for the module.
Differential Revision: https://reviews.llvm.org/D38602
llvm-svn: 315026
Summary: In SamplePGO, when an indirect call is promoted in the profiled binary, before profile annotation, it will be promoted and inlined. For the original indirect call, the current implementation will not mark VP profile on it. This is an issue when profile becomes stale. This patch annotates VP prof on indirect calls during annotation.
Reviewers: tejohnson
Reviewed By: tejohnson
Subscribers: sanjoy, llvm-commits
Differential Revision: https://reviews.llvm.org/D38477
llvm-svn: 315016
The inliner performs some kind of dead code elimination as it goes,
but there are cases that are not really caught by it. We might
at some point consider teaching the inliner about them, but it
is OK for now to run GlobalOpt + GlobalDCE in tandem as their
benefits generally outweight the cost, making the whole pipeline
faster.
This fixes PR34652.
Differential Revision: https://reviews.llvm.org/D38154
llvm-svn: 314997
When ignoring a load that participates in an interleaved group, make sure to
move a cast that needs to sink after it.
Testcase derived from reproducer of PR34743.
Differential Revision: https://reviews.llvm.org/D38338
llvm-svn: 314986
Instead of trying to keep LastWidenRecipe updated after creating each recipe,
have tryToWiden() retrieve the last recipe of the current VPBasicBlock and check
if it's a VPWidenRecipe when attempting to extend its range. This ensures that
such extensions, optimized to maintain the original instruction order, do so
only when the instructions are to maintain their relative order. The latter does
not always hold, e.g., when a cast needs to sink to unravel first order
recurrence (r306884).
Testcase derived from reproducer of PR34711.
Differential Revision: https://reviews.llvm.org/D38339
llvm-svn: 314981
We were using an i1 type and then zero extending to a vector. Instead just create the 0/1 directly as a ConstantInt with the correct type. No need to ask ConstantExpr to zero extend for us.
This bug is a bit tricky to hit because it requires us to visit a zext of an icmp that would normally be simplified to true/false, but that icmp hasnt' been visited yet. In the test case this zext and icmp were created by visiting a udiv and due to worklist ordering we got to the zext first.
Fixes PR34841.
llvm-svn: 314971
Summary: This is to avoid e.g. merging two cheap icmps if the target is not going to expand to something nice later.
Reviewers: dberlin, spatel
Subscribers: davide, nemanjai
Differential Revision: https://reviews.llvm.org/D38232
llvm-svn: 314970
We can support ashr similar to lshr, if we know that none of the shifted in bits are used. In that case SimplifyDemandedBits would normally convert it to lshr. But that conversion doesn't happen if the shift has additional users.
Differential Revision: https://reviews.llvm.org/D38521
llvm-svn: 314945
This is a follow-up to https://reviews.llvm.org/D38138.
I fixed the capitalization of some functions because we're changing those
lines anyway and that helped verify that we weren't accidentally dropping
any options by using default param values.
llvm-svn: 314930
Recommitting r314517 with the fix for handling ConstantExpr.
Original commit message:
Currently, getGEPCost() returns TCC_FREE whenever a GEP is a legal addressing
mode in the target. However, since it doesn't check its actual users, it will
return FREE even in cases where the GEP cannot be folded away as a part of
actual addressing mode. For example, if an user of the GEP is a call
instruction taking the GEP as a parameter, then the GEP may not be folded in
isel.
llvm-svn: 314923
We have found some corner cases connected to range intersection where IRCE makes
a bad thing when the latch condition is unsigned. The fix for that will go as a follow up.
This patch temporarily disables IRCE for unsigned latch conditions until the issue is fixed.
The unsigned latch conditions were introduced to IRCE by rL310027.
Differential Revision: https://reviews.llvm.org/D38529
llvm-svn: 314881
All the buildbots are red, e.g.
http://lab.llvm.org:8011/builders/clang-cmake-aarch64-lld/builds/2436/
> Summary:
> This patch tries to vectorize loads of consecutive memory accesses, accessed
> in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
> which was reverted back due to some basic issue with representing the 'use mask' of
> jumbled accesses.
>
> This patch fixes the mask representation by recording the 'use mask' in the usertree entry.
>
> Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df
>
> Reviewers: mkuper, loladiro, Ayal, zvi, danielcdh
>
> Reviewed By: Ayal
>
> Subscribers: hans, mzolotukhin
>
> Differential Revision: https://reviews.llvm.org/D36130
llvm-svn: 314824
Summary:
This patch tries to vectorize loads of consecutive memory accesses, accessed
in non-consecutive or jumbled way. An earlier attempt was made with patch D26905
which was reverted back due to some basic issue with representing the 'use mask' of
jumbled accesses.
This patch fixes the mask representation by recording the 'use mask' in the usertree entry.
Change-Id: I9fe7f5045f065d84c126fa307ef6ebe0787296df
Reviewers: mkuper, loladiro, Ayal, zvi, danielcdh
Reviewed By: Ayal
Subscribers: hans, mzolotukhin
Differential Revision: https://reviews.llvm.org/D36130
llvm-svn: 314806
Apparently this works by virtue of the fact that the pointers are pointers to the APInts stored inside of the ConstantInt objects. But I really don't think we should be relying on that.
llvm-svn: 314761
Summary: If the merged instruction is call instruction, we need to set the scope to the closes common scope between 2 locations, otherwise it will cause trouble when the call is getting inlined.
Reviewers: dblaikie, aprantl
Reviewed By: dblaikie, aprantl
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D37877
llvm-svn: 314694
Summary: This currently uses ConstantExpr to do its math, but as noted in a TODO it can all be done directly on APInt.
Reviewers: spatel, majnemer
Reviewed By: majnemer
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D38440
llvm-svn: 314640
And follow-up r314585.
Leads to segfaults. I'll forward reproduction instructions to the patch
author.
Also, for a recommit, still add the original patch description.
Otherwise, it becomes really tedious to find out what a patch actually
does. The fact that it is a recommit with a fix is somewhat secondary.
llvm-svn: 314622
Summary: In SamplePGO ThinLTO compile phase, we will not invoke ICP as it may introduce confusion to the 2nd annotation. This patch extracted that logic and makes it clearer before profile annotation. In the mean time, we need to make function importing process both inlined callsites as well as not promoted indirect callsites.
Reviewers: tejohnson
Reviewed By: tejohnson
Subscribers: sanjoy, mehdi_amini, llvm-commits, inglorion
Differential Revision: https://reviews.llvm.org/D38094
llvm-svn: 314619
This patch will eliminate redundant intptr/ptrtoint that pessimizes
analyses such as SCEV, AA and will make optimization passes such
as auto-vectorization more powerful.
Differential revision: http://reviews.llvm.org/D37832
llvm-svn: 314561
When type shrinking reductions, we should insert the truncations and extends at
the end of the loop latch block. Previously, these instructions were inserted
at the end of the loop header block. The difference is only a problem for loops
with predicated instructions (e.g., conditional stores and instructions that
may divide by zero). For these instructions, we create new basic blocks inside
the vectorized loop, which cause the loop header and latch to no longer be the
same block. This should fix PR34687.
Reference: https://bugs.llvm.org/show_bug.cgi?id=34687
llvm-svn: 314542
The type of a SCEVConstant may not match the corresponding LLVM Value.
In this case, we skip the constant folding for now.
TODO: Replace ConstantInt Zero by ConstantPointerNull
llvm-svn: 314531
Summary:
Currently, getGEPCost() returns TCC_FREE whenever a GEP is a legal addressing mode in the target.
However, since it doesn't check its actual users, it will return FREE even in cases
where the GEP cannot be folded away as a part of actual addressing mode.
For example, if an user of the GEP is a call instruction taking the GEP as a parameter,
then the GEP may not be folded in isel.
Reviewers: hfinkel, efriedma, mcrosier, jingyue, haicheng
Reviewed By: hfinkel
Subscribers: javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D38085
llvm-svn: 314517
JumpThreading now preserves dominance and lazy value information across the
entire pass. The pass manager is also informed of this preservation with
the goal of DT and LVI being recalculated fewer times overall during
compilation.
This change prepares JumpThreading for enhanced opportunities; particularly
those across loop boundaries.
Patch by: Brian Rzycki <b.rzycki@samsung.com>,
Sebastian Pop <s.pop@samsung.com>
Differential revision: https://reviews.llvm.org/D37528
llvm-svn: 314435
Summary:
And now that we no longer have to explicitly free() the Loop instances, we can
(with more ease) use the destructor of LoopBase to do what LoopBase::clear() was
doing.
Reviewers: chandlerc
Subscribers: mehdi_amini, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D38201
llvm-svn: 314375
This reverts r314017 and similar code added in later commits. It seems to not work for pointer compares and is causing a bot failure for the last several days.
llvm-svn: 314360
reductions.
If both operands of the newly created SelectInst are Undefs the
resulting operation is also Undef, not SelectInst. It may cause crashes
when trying to propagate IR flags because function expects exactly
SelectInst instruction, nothing else.
llvm-svn: 314323
These changes faciliate positive behavior for arithmetic based select
expressions that match its translation criteria, keeping code size gated to
neutral or improved scenarios.
Patch by Michael Berg <michael_c_berg@apple.com>!
Differential Revision: https://reviews.llvm.org/D38263
llvm-svn: 314320
This was intended to be no-functional-change, but it's not - there's a test diff.
So I thought I should stop here and post it as-is to see if this looks like what was expected
based on the discussion in PR34603:
https://bugs.llvm.org/show_bug.cgi?id=34603
Notes:
1. The test improvement occurs because the existing 'LateSimplifyCFG' marker is not carried
through the recursive calls to 'SimplifyCFG()->SimplifyCFGOpt().run()->SimplifyCFG()'.
The parameter isn't passed down, so we pick up the default value from the function signature
after the first level. I assumed that was a bug, so I've passed 'Options' down in all of the
'SimplifyCFG' calls.
2. I split 'LateSimplifyCFG' into 2 bits: ConvertSwitchToLookupTable and KeepCanonicalLoops.
This would theoretically allow us to differentiate the transforms controlled by those params
independently.
3. We could stash the optional AssumptionCache pointer and 'LoopHeaders' pointer in the struct too.
I just stopped here to minimize the diffs.
4. Similarly, I stopped short of messing with the pass manager layer. I have another question that
could wait for the follow-up: why is the new pass manager creating the pass with LateSimplifyCFG
set to true no matter where in the pipeline it's creating SimplifyCFG passes?
// Create an early function pass manager to cleanup the output of the
// frontend.
EarlyFPM.addPass(SimplifyCFGPass());
-->
/// \brief Construct a pass with the default thresholds
/// and switch optimizations.
SimplifyCFGPass::SimplifyCFGPass()
: BonusInstThreshold(UserBonusInstThreshold),
LateSimplifyCFG(true) {} <-- switches get converted to lookup tables and loops may not be in canonical form
If this is unintended, then it's possible that the current behavior of dropping the 'LateSimplifyCFG'
setting via recursion was masking this bug.
Differential Revision: https://reviews.llvm.org/D38138
llvm-svn: 314308
This patch tries to transform cases like:
for (unsigned i = 0; i < N; i += 2) {
bool c0 = (i & 0x1) == 0;
bool c1 = ((i + 1) & 0x1) == 1;
}
To
for (unsigned i = 0; i < N; i += 2) {
bool c0 = true;
bool c1 = true;
}
This commit also update test/Transforms/IndVarSimplify/replace-srem-by-urem.ll to prevent constant folding.
Differential Revision: https://reviews.llvm.org/D38272
llvm-svn: 314266
Summary:
Don't bail out on constant divisors for divisions that can be narrowed without
introducing control flow . This gives us a 32 bit multiply instead of an
emulated 64 bit multiply in the generated PTX assembly.
Reviewers: jlebar
Subscribers: jholewinski, mcrosier, llvm-commits
Differential Revision: https://reviews.llvm.org/D38265
llvm-svn: 314253
If this transformation succeeds, we're going to remove our dependency on the shift by rewriting the and. So it doesn't matter how many uses the shift has.
This distributes the one use check to other transforms in foldICmpAndConstConst that do need it.
Differential Revision: https://reviews.llvm.org/D38206
llvm-svn: 314233
This is a 2nd attempt at:
https://reviews.llvm.org/rL310055
...which was reverted at rL310123 because of PR34074:
https://bugs.llvm.org/show_bug.cgi?id=34074
In this version, we break out of the inner loop after we successfully merge and kill a pair of stores. In the
earlier rev, we were continuing instead, which meant we could process the invalid info from a now dead store.
Original commit message (authored by Filipe Cabecinhas):
This fixes PR31777.
If both stores' values are ConstantInt, we merge the two stores
(shifting the smaller store appropriately) and replace the earlier (and
larger) store with an updated constant.
In the future we should also support vectors of integers. And maybe
float/double if we can.
Differential Revision: https://reviews.llvm.org/D30703
llvm-svn: 314206
Usually the frontend communicates the size of wchar_t via metadata and
we can optimize wcslen (and possibly other calls in the future). In
cases without the wchar_size metadata we would previously try to guess
the correct size based on the target triple; however this is fragile to
keep up to date and may miss users manually changing the size via flags.
Better be safe and stop guessing and optimizing if the frontend didn't
communicate the size.
Differential Revision: https://reviews.llvm.org/D38106
llvm-svn: 314185
Summary:
Sanitizer blacklist entries currently apply to all sanitizers--there
is no way to specify that an entry should only apply to a specific
sanitizer. This is important for Control Flow Integrity since there are
several different CFI modes that can be enabled at once. For maximum
security, CFI blacklist entries should be scoped to only the specific
CFI mode(s) that entry applies to.
Adding section headers to SpecialCaseLists allows users to specify more
information about list entries, like sanitizer names or other metadata,
like so:
[section1]
fun:*fun1*
[section2|section3]
fun:*fun23*
The section headers are regular expressions. For backwards compatbility,
blacklist entries entered before a section header are put into the '[*]'
section so that blacklists without sections retain the same behavior.
SpecialCaseList has been modified to also accept a section name when
matching against the blacklist. It has also been modified so the
follow-up change to clang can define a derived class that allows
matching sections by SectionMask instead of by string.
Reviewers: pcc, kcc, eugenis, vsk
Reviewed By: eugenis, vsk
Subscribers: vitalybuka, llvm-commits
Differential Revision: https://reviews.llvm.org/D37924
llvm-svn: 314170
All this optimization cares about is knowing how many low bits of LHS is known to be zero and whether that means that the result is 0 or greater than the RHS constant. It doesn't matter where the zeros in the low bits came from. So we don't need to specifically look for an AND. Instead we can use known bits.
Differential Revision: https://reviews.llvm.org/D38195
llvm-svn: 314153
The 1st attempt at this:
https://reviews.llvm.org/rL314117
was reverted at:
https://reviews.llvm.org/rL314118
because of bot fails for clang tests that were checking optimized IR. That should be fixed with:
https://reviews.llvm.org/rL314144
...so try again.
Original commit message:
The transform to convert an extract-of-a-select-of-vectors was added at:
https://reviews.llvm.org/rL194013
And a question about the validity of this transform was raised in the review:
https://reviews.llvm.org/D1539:
...but not answered AFAICT>
Most of the motivating cases in that patch are now handled by other combines. These are the tests that were added with
the original commit, but they are not regressing even after we remove the transform in this patch.
The diffs we see after removing this transform cause us to avoid increasing the instruction count, so we don't want to do
those transforms as canonicalizations.
The motivation for not turning a vector-select-of-vectors into a scalar operation is shown in PR33301:
https://bugs.llvm.org/show_bug.cgi?id=33301
...in those cases, we'll get vector ops with this patch rather than the vector/scalar mix that we currently see.
Differential Revision: https://reviews.llvm.org/D38006
llvm-svn: 314147
Since now SCEV can handle 'urem', an 'urem' is a better canonical form than an 'srem' because it has well-defined behavior
This is a follow up of D34598
Differential Revision: https://reviews.llvm.org/D38072
llvm-svn: 314125
The transform to convert an extract-of-a-select-of-vectors was added at:
rL194013
And a question about the validity of this transform was raised in the review:
https://reviews.llvm.org/D1539:
...but not answered AFAICT>
Most of the motivating cases in that patch are now handled by other combines. These are the tests that were added with
the original commit, but they are not regressing even after we remove the transform in this patch.
The diffs we see after removing this transform cause us to avoid increasing the instruction count, so we don't want to do
those transforms as canonicalizations.
The motivation for not turning a vector-select-of-vectors into a scalar operation is shown in PR33301:
https://bugs.llvm.org/show_bug.cgi?id=33301
...in those cases, we'll get vector ops with this patch rather than the vector/scalar mix that we currently see.
Differential Revision: https://reviews.llvm.org/D38006
llvm-svn: 314117
Max Kazantsev