Commit Graph

25091 Commits

Author SHA1 Message Date
Florian Hahn 43aa7227df [DSE,MemorySSA] Check if Current is valid for elimination first.
This changes getDomMemoryDef to check if a Current is a valid
candidate for elimination before checking for reads. Before the change,
we were spending a lot of compile-time in checking for read accesses for
Current that might not even be removable.

This patch flips the logic, so we skip Current if they cannot be
removed before checking all their uses. This is much more efficient in
practice.

It also adds a more aggressive limit for checking partially overlapping
stores. The main problem with overlapping stores is that we do not know
if they will lead to elimination until seeing all of them. This patch
limits adds a new limit for overlapping store candidates, which keeps
the number of modified overlapping stores roughly the same.

This is another substantial compile-time improvement (while also
increasing the number of stores eliminated). Geomean -O3 -0.67%,
ReleaseThinLTO -0.97%.

http://llvm-compile-time-tracker.com/compare.php?from=0a929b6978a068af8ddb02d0d4714a2843dd8ba9&to=2e630629b43f64b60b282e90f0d96082fde2dacc&stat=instructions

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D86487
2020-08-28 11:19:04 +01:00
Florian Hahn 20e989e9de [BuildLibCalls] Add argmemonly to more lib calls.
strspn, strncmp, strcspn, strcasecmp, strncasecmp, memcmp, memchr,
memrchr, memcpy, memmove, memcpy, mempcpy, strchr, strrchr, bcmp
should all only access memory through their arguments.

I broke out strcoll, strcasecmp, strncasecmp because the result
depends on the locale, which might get accessed through memory.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D86724
2020-08-28 09:50:38 +01:00
Shinji Okumura 50ebd1afa9 [Attributor] Do not manifest noundef for dead positions
Even if noundef is deduced for a position, we should not manifest it when the position is dead.
This is because the associated values with dead positions are replaced with undef values by AAIsDead.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D86565
2020-08-28 05:58:18 +09:00
Christopher Tetreault 035833ae42 [SVE] Remove bad call to VectorType::getNumElements() from HeapProfiler
Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D86727
2020-08-27 12:16:00 -07:00
Shinji Okumura c5e6872ec6 [Attributor] Guarantee getAAFor not to update AA in the manifestation stage
If we query an AA with `Attributor::getAAFor` in `AbstractAttribute::manifest`, the AA may be updated.
This patch makes use of the phase flag in Attributor, and handle `getAAFor` behavior according to the flag.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D86635
2020-08-28 04:07:42 +09:00
Christopher Tetreault 5e63083435 [SVE] Remove calls to VectorType::getNumElements from Transforms/Vectorize
Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D82056
2020-08-27 12:02:20 -07:00
Teresa Johnson 5b9d462b7d [HeapProf] Fix bot failures from instrumentation pass
Fix bot failure from 7ed8124d46f94601d5f1364becee9cee8538265e:
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-ubuntu/builds/8533

Since we are always using dynamic shadow,
insertDynamicShadowAtFunctionEntry should always return true for
modifying the function.
2020-08-27 10:21:19 -07:00
Shinji Okumura 7a68f0f1e0 [Attributor] Add a phase flag to Attributor
Add a new flag that indicates which stage in the process we are in.
This flag is introduced for handling behavior of `getAAFor` according to the stage. (discussed in D86635)

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D86678
2020-08-28 01:16:38 +09:00
Teresa Johnson 7ed8124d46 [HeapProf] Clang and LLVM support for heap profiling instrumentation
See RFC for background:
http://lists.llvm.org/pipermail/llvm-dev/2020-June/142744.html

Note that the runtime changes will be sent separately (hopefully this
week, need to add some tests).

This patch includes the LLVM pass to instrument memory accesses with
either inline sequences to increment the access count in the shadow
location, or alternatively to call into the runtime. It also changes
calls to memset/memcpy/memmove to the equivalent runtime version.
The pass is modeled on the address sanitizer pass.

The clang changes add the driver option to invoke the new pass, and to
link with the upcoming heap profiling runtime libraries.

Currently there is no attempt to optimize the instrumentation, e.g. to
aggregate updates to the same memory allocation. That will be
implemented as follow on work.

Differential Revision: https://reviews.llvm.org/D85948
2020-08-27 08:50:35 -07:00
Florian Hahn 419c6948df [SimplifyLibCalls] Remove over-eager early return in strlen optzns.
Currently we bail out early for strlen calls with a GEP operand, if none
of the GEP specific optimizations fire. But there could be later
optimizations that still apply,  which we currently miss out on.

An example is that we do not apply the following optimization
   strlen(x) == 0 --> *x == 0

Unless I am missing something, there seems to be no reason for bailing
out early there.

Fixes PR47149.

Reviewed By: lebedev.ri, xbolva00

Differential Revision: https://reviews.llvm.org/D85886
2020-08-27 15:19:45 +01:00
serge-sans-paille 4e29d25669 Fix OpenMP deduplicateRuntimeCalls return status
Differential Revision: https://reviews.llvm.org/D86705
2020-08-27 15:01:04 +02:00
serge-sans-paille 5621571fc7 Fix Attributor return status
Differential Revision: https://reviews.llvm.org/D86703
2020-08-27 15:01:04 +02:00
Florian Hahn bb024c3c4e [DSE,MemorySSA] Remove short-cut to check if all paths are covered.
The post-order number early continue does not work in some cases, e.g.
if a path from EarlierAccess to an exit includes a node that dominates
EarlierAccess in a cycle.

The short-cut only has very minor impact on compile-time, so it seems
straight-forward to remove it for now:

http://llvm-compile-time-tracker.com/compare.php?from=062412e79fcfedf2cf004433e42036b0333e3f83&to=d7386016a77ce1387bdbbf360f1de157faea9d31&stat=instructions

Fixes PR47285.
2020-08-27 12:42:40 +01:00
Florian Hahn e717fdb0f1 [DSE,MemorySSA] Traverse use-def chain without MemSSA Walker.
For DSE with MemorySSA it is beneficial to manually traverse the
defining access, instead of using a MemorySSA walker, so we can
better control the number of steps together with other limits and
also weed out invalid/unprofitable paths early on.

This patch requires a follow-up patch to be most effective, which I will
share soon after putting this patch up.

This temporarily XFAIL's the limit tests, because we now explore more
MemoryDefs that may not alias/clobber the killing def. This will be
improved/fixed by the follow-up patch.

This patch also renames some `Dom*` variables to `Earlier*`, because the
dominance relation is not really used/important here and potentially
confusing.

This patch allows us to aggressively cut down compile time, geomean
-O3 -0.64%, ReleaseThinLTO -1.65%, at the expense of fewer stores
removed. Subsequent patches will increase the number of removed stores
again, while keeping compile-time in check.

http://llvm-compile-time-tracker.com/compare.php?from=d8e3294118a8c5f3f97688a704d5a05b67646012&to=0a929b6978a068af8ddb02d0d4714a2843dd8ba9&stat=instructions

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D86486
2020-08-27 10:02:02 +01:00
Shinji Okumura 6c25eca614 [Attributor] Add flag for undef value to the state of AAPotentialValues
Currently, an undef value is reduced to 0 when it is added to a set of potential values.
This patch introduces a flag for under values. By this, for example, we can merge two states `{undef}`, `{1}` to `{1}` (because we can reduce the undef to 1).

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D85592
2020-08-27 16:30:29 +09:00
Arthur Eubanks 486ed88533 [ConstProp] Remove ConstantPropagation
As discussed in
http://lists.llvm.org/pipermail/llvm-dev/2020-July/143801.html.

Currently no users outside of unit tests.

Replace all instances in tests of -constprop with -instsimplify.
Notable changes in tests:
* vscale.ll - @llvm.sadd.sat.nxv16i8 is evaluated by instsimplify, use a fake intrinsic instead
* InsertElement.ll - insertelement undef is removed by instsimplify in @insertelement_undef
llvm/test/Transforms/ConstProp moved to llvm/test/Transforms/InstSimplify/ConstProp

Reviewed By: lattner, nikic

Differential Revision: https://reviews.llvm.org/D85159
2020-08-26 15:51:30 -07:00
Wei Mi c67ccf5faf [SampleFDO] Enhance profile remapping support for searching inline instance
and indirect call promotion candidate.

Profile remapping is a feature to match a function in the module with its
profile in sample profile if the function name and the name in profile look
different but are equivalent using given remapping rules. This is a useful
feature to keep the performance stable by specifying some remapping rules
when sampleFDO targets are going through some large scale function signature
change.

However, currently profile remapping support is only valid for outline
function profile in SampleFDO. It cannot match a callee with an inline
instance profile if they have different but equivalent names. We found
that without the support for inline instance profile, remapping is less
effective for some large scale change.

To add that support, before any remapping lookup happens, all the names
in the profile will be inserted into remapper and the Key to the name
mapping will be recorded in a map called NameMap in the remapper. During
name lookup, a Key will be returned for the given name and it will be used
to extract an equivalent name in the profile from NameMap. So with the help
of the NameMap, we can translate any given name to an equivalent name in
the profile if it exists. Whenever we try to match a name in the module to
a name in the profile, we will try the match with the original name first,
and if it doesn't match, we will use the equivalent name got from remapper
to try the match for another time. In this way, the patch can enhance the
profile remapping support for searching inline instance and searching
indirect call promotion candidate.

In a planned large scale change of int64 type (long long) to int64_t (long),
we found the performance of a google internal benchmark degraded by 2% if
nothing was done. If existing profile remapping was enabled, the performance
degradation dropped to 1.2%. If the profile remapping with the current patch
was enabled, the performance degradation further dropped to 0.14% (Note the
experiment was done before searching indirect call promotion candidate was
added. We hope with the remapping support of searching indirect call promotion
candidate, the degradation can drop to 0% in the end. It will be evaluated
post commit).

Differential Revision: https://reviews.llvm.org/D86332
2020-08-26 11:07:35 -07:00
Roman Lebedev 95848ea101
[Value][InstCombine] Fix one-use checks in PHI-of-op -> Op-of-PHI[s] transforms to be one-user checks
As FIXME said, they really should be checking for a single user,
not use, so let's do that. It is not *that* unusual to have
the same value as incoming value in a PHI node, not unlike
how a PHI may have the same incoming basic block more than once.

There isn't a nice way to do that, Value::users() isn't uniqified,
and Value only tracks it's uses, not Users, so the check is
potentially costly since it does indeed potentially involes
traversing the entire use list of a value.
2020-08-26 20:20:41 +03:00
Sjoerd Meijer bda8fbe2d2 [LV] Fallback strategies if tail-folding fails
This implements 2 different vectorisation fallback strategies if tail-folding
fails: 1) don't vectorise at all, or 2) vectorise using a scalar epilogue. This
can be controlled with option -prefer-predicate-over-epilogue, that has been
changed to take a numeric value corresponding to the tail-folding preference
and preferred fallback.

Patch by: Pierre van Houtryve, Sjoerd Meijer.

Differential Revision: https://reviews.llvm.org/D79783
2020-08-26 16:55:25 +01:00
Shinji Okumura 3050713798 [Attributor] Provide an edge-based interface in AAIsDead
This patch produces an edge-based interface in AAIsDead.
By this, we can query a set of basic blocks that are directly reachable from a given basic block.
This is specifically useful for implementation of AAReachability.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D85547
2020-08-26 16:57:52 +09:00
Roman Lebedev 1f90d45b9e
[InstCombine] PHI-of-extractvalues -> extractvalue-of-PHI, aka invokes are bad
While since D86306 we do it's sibling fold for `insertvalue`,
we should also do this for `extractvalue`'s.

And unlike that one, the results here are, quite honestly, shocking,
as it can be observed here on vanilla llvm test-suite + RawSpeed results:

```
| statistic name                                     | baseline  | proposed  |       Δ |       % |    |%| |
|----------------------------------------------------|-----------|-----------|--------:|--------:|-------:|
| asm-printer.EmittedInsts                           | 7945095   | 7942507   |   -2588 |  -0.03% |  0.03% |
| assembler.ObjectBytes                              | 273209920 | 273069800 | -140120 |  -0.05% |  0.05% |
| early-cse.NumCSE                                   | 2183363   | 2183398   |      35 |   0.00% |  0.00% |
| early-cse.NumSimplify                              | 541847    | 550017    |    8170 |   1.51% |  1.51% |
| instcombine.NumAggregateReconstructionsSimplified  | 2139      | 108       |   -2031 | -94.95% | 94.95% |
| instcombine.NumCombined                            | 3601364   | 3635448   |   34084 |   0.95% |  0.95% |
| instcombine.NumConstProp                           | 27153     | 27157     |       4 |   0.01% |  0.01% |
| instcombine.NumDeadInst                            | 1694521   | 1765022   |   70501 |   4.16% |  4.16% |
| instcombine.NumPHIsOfExtractValues                 | 0         | 37546     |   37546 |   0.00% |  0.00% |
| instcombine.NumSunkInst                            | 63158     | 63686     |     528 |   0.84% |  0.84% |
| instcount.NumBrInst                                | 874304    | 871857    |   -2447 |  -0.28% |  0.28% |
| instcount.NumCallInst                              | 1757657   | 1758402   |     745 |   0.04% |  0.04% |
| instcount.NumExtractValueInst                      | 45623     | 11483     |  -34140 | -74.83% | 74.83% |
| instcount.NumInsertValueInst                       | 4983      | 580       |   -4403 | -88.36% | 88.36% |
| instcount.NumInvokeInst                            | 61018     | 59478     |   -1540 |  -2.52% |  2.52% |
| instcount.NumLandingPadInst                        | 35334     | 34215     |   -1119 |  -3.17% |  3.17% |
| instcount.NumPHIInst                               | 344428    | 331116    |  -13312 |  -3.86% |  3.86% |
| instcount.NumRetInst                               | 100773    | 100772    |      -1 |   0.00% |  0.00% |
| instcount.TotalBlocks                              | 1081154   | 1077166   |   -3988 |  -0.37% |  0.37% |
| instcount.TotalFuncs                               | 101443    | 101442    |      -1 |   0.00% |  0.00% |
| instcount.TotalInsts                               | 8890201   | 8833747   |  -56454 |  -0.64% |  0.64% |
| instsimplify.NumSimplified                         | 75822     | 75707     |    -115 |  -0.15% |  0.15% |
| simplifycfg.NumHoistCommonCode                     | 24203     | 24197     |      -6 |  -0.02% |  0.02% |
| simplifycfg.NumHoistCommonInstrs                   | 48201     | 48195     |      -6 |  -0.01% |  0.01% |
| simplifycfg.NumInvokes                             | 2785      | 4298      |    1513 |  54.33% | 54.33% |
| simplifycfg.NumSimpl                               | 997332    | 1018189   |   20857 |   2.09% |  2.09% |
| simplifycfg.NumSinkCommonCode                      | 7088      | 6464      |    -624 |  -8.80% |  8.80% |
| simplifycfg.NumSinkCommonInstrs                    | 15117     | 14021     |   -1096 |  -7.25% |  7.25% |
```
... which tells us that this new fold fires whopping 38k times,
increasing the amount of SimplifyCFG's `invoke`->`call` transforms by +54% (+1513) (again, D85787 did that last time),
decreasing total instruction count by -0.64% (-56454),
and sharply decreasing count of `insertvalue`'s (-88.36%, i.e. 9 times less)
and `extractvalue`'s (-74.83%, i.e. four times less).

This causes geomean -0.01% binary size decrease
http://llvm-compile-time-tracker.com/compare.php?from=4d5ca22b8adfb6643466e4e9f48ba14bb48938bc&to=97dacca0111cb2ae678204e52a3cee00e3a69208&stat=size-text
and, ignoring `O0-g`, is a geomean -0.01%..-0.05% compile-time improvement
http://llvm-compile-time-tracker.com/compare.php?from=4d5ca22b8adfb6643466e4e9f48ba14bb48938bc&to=97dacca0111cb2ae678204e52a3cee00e3a69208&stat=instructions

The other thing that tells is, is that while this is a massive win for `invoke`->`call` transform
`InstCombinerImpl::foldAggregateConstructionIntoAggregateReuse()` fold,
which is supposed to be dealing with such aggregate reconstructions,
fires a lot less now. There are two reasons why:
1. After this fold, as it can be seen in tests, we may (will) end up with trivially redundant PHI nodes.
   We don't CSE them in InstCombine presently, which means that EarlyCSE needs to run and then InstCombine rerun.
2. But then, EarlyCSE not only manages to fold such redundant PHI's,
   it also sees that the extract-insert chain recreates the original aggregate,
   and replaces it with the original aggregate.

The take-aways are
1. We maybe should do most trivial, same-BB PHI CSE in InstCombine
2. I need to check if what other patterns remain, and how they can be resolved.
   (i.e. i wonder if `foldAggregateConstructionIntoAggregateReuse()` might go away)

This is a reland of the original commit fcb51d8c24,
because originally i forgot to ensure that the base aggregate types match.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D86530
2020-08-26 09:57:50 +03:00
Roman Lebedev c295c6f2c0
Revert "[InstCombine] PHI-of-extractvalues -> extractvalue-of-PHI, aka invokes are bad"
This reverts commit fcb51d8c24.

As buildbots report, there's apparently some missing check to ensure
that the types of incoming values match the type of PHI.
Let's revert for a moment.
2020-08-26 09:23:22 +03:00
Roman Lebedev fcb51d8c24
[InstCombine] PHI-of-extractvalues -> extractvalue-of-PHI, aka invokes are bad
While since D86306 we do it's sibling fold for `insertvalue`,
we should also do this for `extractvalue`'s.

And unlike that one, the results here are, quite honestly, shocking,
as it can be observed here on vanilla llvm test-suite + RawSpeed results:

```
| statistic name                                     | baseline  | proposed  |       Δ |       % |    |%| |
|----------------------------------------------------|-----------|-----------|--------:|--------:|-------:|
| asm-printer.EmittedInsts                           | 7945095   | 7942507   |   -2588 |  -0.03% |  0.03% |
| assembler.ObjectBytes                              | 273209920 | 273069800 | -140120 |  -0.05% |  0.05% |
| early-cse.NumCSE                                   | 2183363   | 2183398   |      35 |   0.00% |  0.00% |
| early-cse.NumSimplify                              | 541847    | 550017    |    8170 |   1.51% |  1.51% |
| instcombine.NumAggregateReconstructionsSimplified  | 2139      | 108       |   -2031 | -94.95% | 94.95% |
| instcombine.NumCombined                            | 3601364   | 3635448   |   34084 |   0.95% |  0.95% |
| instcombine.NumConstProp                           | 27153     | 27157     |       4 |   0.01% |  0.01% |
| instcombine.NumDeadInst                            | 1694521   | 1765022   |   70501 |   4.16% |  4.16% |
| instcombine.NumPHIsOfExtractValues                 | 0         | 37546     |   37546 |   0.00% |  0.00% |
| instcombine.NumSunkInst                            | 63158     | 63686     |     528 |   0.84% |  0.84% |
| instcount.NumBrInst                                | 874304    | 871857    |   -2447 |  -0.28% |  0.28% |
| instcount.NumCallInst                              | 1757657   | 1758402   |     745 |   0.04% |  0.04% |
| instcount.NumExtractValueInst                      | 45623     | 11483     |  -34140 | -74.83% | 74.83% |
| instcount.NumInsertValueInst                       | 4983      | 580       |   -4403 | -88.36% | 88.36% |
| instcount.NumInvokeInst                            | 61018     | 59478     |   -1540 |  -2.52% |  2.52% |
| instcount.NumLandingPadInst                        | 35334     | 34215     |   -1119 |  -3.17% |  3.17% |
| instcount.NumPHIInst                               | 344428    | 331116    |  -13312 |  -3.86% |  3.86% |
| instcount.NumRetInst                               | 100773    | 100772    |      -1 |   0.00% |  0.00% |
| instcount.TotalBlocks                              | 1081154   | 1077166   |   -3988 |  -0.37% |  0.37% |
| instcount.TotalFuncs                               | 101443    | 101442    |      -1 |   0.00% |  0.00% |
| instcount.TotalInsts                               | 8890201   | 8833747   |  -56454 |  -0.64% |  0.64% |
| instsimplify.NumSimplified                         | 75822     | 75707     |    -115 |  -0.15% |  0.15% |
| simplifycfg.NumHoistCommonCode                     | 24203     | 24197     |      -6 |  -0.02% |  0.02% |
| simplifycfg.NumHoistCommonInstrs                   | 48201     | 48195     |      -6 |  -0.01% |  0.01% |
| simplifycfg.NumInvokes                             | 2785      | 4298      |    1513 |  54.33% | 54.33% |
| simplifycfg.NumSimpl                               | 997332    | 1018189   |   20857 |   2.09% |  2.09% |
| simplifycfg.NumSinkCommonCode                      | 7088      | 6464      |    -624 |  -8.80% |  8.80% |
| simplifycfg.NumSinkCommonInstrs                    | 15117     | 14021     |   -1096 |  -7.25% |  7.25% |
```
... which tells us that this new fold fires whopping 38k times,
increasing the amount of SimplifyCFG's `invoke`->`call` transforms by +54% (+1513) (again, D85787 did that last time),
decreasing total instruction count by -0.64% (-56454),
and sharply decreasing count of `insertvalue`'s (-88.36%, i.e. 9 times less)
and `extractvalue`'s (-74.83%, i.e. four times less).

This causes geomean -0.01% binary size decrease
http://llvm-compile-time-tracker.com/compare.php?from=4d5ca22b8adfb6643466e4e9f48ba14bb48938bc&to=97dacca0111cb2ae678204e52a3cee00e3a69208&stat=size-text
and, ignoring `O0-g`, is a geomean -0.01%..-0.05% compile-time improvement
http://llvm-compile-time-tracker.com/compare.php?from=4d5ca22b8adfb6643466e4e9f48ba14bb48938bc&to=97dacca0111cb2ae678204e52a3cee00e3a69208&stat=instructions

The other thing that tells is, is that while this is a massive win for `invoke`->`call` transform
`InstCombinerImpl::foldAggregateConstructionIntoAggregateReuse()` fold,
which is supposed to be dealing with such aggregate reconstructions,
fires a lot less now. There are two reasons why:
1. After this fold, as it can be seen in tests, we may (will) end up with trivially redundant PHI nodes.
   We don't CSE them in InstCombine presently, which means that EarlyCSE needs to run and then InstCombine rerun.
2. But then, EarlyCSE not only manages to fold such redundant PHI's,
   it also sees that the extract-insert chain recreates the original aggregate,
   and replaces it with the original aggregate.

The take-aways are
1. We maybe should do most trivial, same-BB PHI CSE in InstCombine
2. I need to check if what other patterns remain, and how they can be resolved.
   (i.e. i wonder if `foldAggregateConstructionIntoAggregateReuse()` might go away)

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D86530
2020-08-26 09:08:24 +03:00
Juneyoung Lee f753f5b050 [ValueTracking] Let getGuaranteedNonPoisonOp find multiple non-poison operands
This patch helps getGuaranteedNonPoisonOp find multiple non-poison operands.

Instead of special-casing llvm.assume, I think it is also a viable option to
add noundef to Intrinsics.td. If it makes sense, I'll make a patch for that.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D86477
2020-08-26 04:40:21 +09:00
Sanjay Patel c4f0a0896f [InstCombine] improve demanded element analysis for vector insert-of-extract (2nd try)
The 1st attempt (rG557b890) was reverted because it caused miscompiles.
That bug is avoided here by changing the order of folds and as verified
in the new tests.

Original commit message:
InstCombine currently has odd rules for folding insert-extract chains to shuffles,
so we miss collapsing seemingly simple cases as shown in the tests here.

But poison makes this not quite as easy as we might have guessed. Alive2 tests to
show the subtle difference (similar to the regression tests):
https://alive2.llvm.org/ce/z/hp4hv3 (this is ok)
https://alive2.llvm.org/ce/z/ehEWaN (poison leakage)

SLP tends to create these patterns (as shown in the SLP tests), and this could
help with solving PR16739.

Differential Revision: https://reviews.llvm.org/D86460
2020-08-25 11:19:36 -04:00
Sjoerd Meijer ae366479e8 [LV] get.active.lane.mask consuming tripcount instead of backedge-taken count
This adapts LV to the new semantics of get.active.lane.mask as discussed in
D86147, which means that the LV now emits intrinsic get.active.lane.mask with
the loop tripcount instead of the backedge-taken count as its second argument.
The motivation for this is described in D86147.

Differential Revision: https://reviews.llvm.org/D86304
2020-08-25 13:49:19 +01:00
Shinji Okumura 05390440a2 [Attributor][NFC] Clang format 2020-08-25 19:32:58 +09:00
Benjamin Kramer c6fb72de4f Revert "[InstCombine] improve demanded element analysis for vector insert-of-extract"
This reverts commit 557b890ff4. Causing
miscompiles, test case is on llvm-commits.
2020-08-25 11:31:31 +02:00
David Sherwood 7b64765cd1 [SVE] Fix TypeSize related warnings with IR truncates of scalable vectors
In getCastInstrCost when the instruction is a truncate we were relying
upon the implicit TypeSize -> uint64_t cast when asking if a given type
has the same size as a legal integer. I've changed the code to only
ask the question if the type is fixed length.

I have also changed InstCombinerImpl::SimplifyDemandedUseBits to bail
out for now if the type is a scalable vector.

I've added the following new tests:

  Analysis/CostModel/AArch64/sve-trunc.ll
  Transforms/InstCombine/AArch64/sve-trunc.ll

for both of these fixes.

Differential revision: https://reviews.llvm.org/D86432
2020-08-25 09:17:56 +01:00
Florian Hahn e19ef1aab5 [DSE,MemorySSA] Cache accesses with/without reachable read-clobbers.
Currently we repeatedly check the same uses for read clobbers in some
cases. We can avoid unnecessary checks by keeping track of the memory
accesses we already found read clobbers for. To do so, we just add
memory access causing read-clobbers to a set. Note that marking all
visited accesses as read-clobbers would be to pessimistic, as that might
include accesses not on any path to  the actual read clobber.

If we do not find any read-clobbers, we can add all visited instructions
to another set and use that to skip the same accesses in the next call.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D75025
2020-08-25 08:48:46 +01:00
Roman Lebedev cdd339c568
[InstCombine] PHI-of-insertvalues -> insertvalue-of-PHI's
As per statistic, this happens pretty exceedingly rare,
but i have seen it in exactly the situations the
Phi-aware aggregate reconstruction would have handled,
eventually, and allowed invoke -> call fold later on.

So while this might be something that other fold
will have to learn about, i believe we should be
doing this transform in general.

Here, we are okay with adding two PHI's to get both the base aggregate,
and the inserted value. I'm not sure it makes much sense to restrict
it to a single phi (to just the inserted value?), because originally
we'd be receiving the final aggregate already..

llvm test-suite + RawSpeed:
```
| statistic name                             | baseline  | proposed  |    Δ |      % | \|%\| |
|--------------------------------------------|-----------|-----------|-----:|-------:|------:|
| instcombine.NumPHIsOfInsertValues          | 0         | 12        |  12  |  0.00% | 0.00% |
| asm-printer.EmittedInsts                   | 8926643   | 8926595   | -48  |  0.00% | 0.00% |
| instcombine.NumCombined                    | 3846614   | 3846640   |  26  |  0.00% | 0.00% |
| instcombine.NumConstProp                   | 24302     | 24293     |  -9  | -0.04% | 0.04% |
| instcombine.NumDeadInst                    | 1620140   | 1620112   | -28  |  0.00% | 0.00% |
| instcount.NumBrInst                        | 898466    | 898464    |  -2  |  0.00% | 0.00% |
| instcount.NumCallInst                      | 1760819   | 1760875   |  56  |  0.00% | 0.00% |
| instcount.NumExtractValueInst              | 45659     | 45649     | -10  | -0.02% | 0.02% |
| instcount.NumInsertValueInst               | 4991      | 4981      | -10  | -0.20% | 0.20% |
| instcount.NumIntToPtrInst                  | 27084     | 27087     |   3  |  0.01% | 0.01% |
| instcount.NumPHIInst                       | 371435    | 371429    |  -6  |  0.00% | 0.00% |
| instcount.NumStoreInst                     | 906011    | 906019    |   8  |  0.00% | 0.00% |
| instcount.TotalBlocks                      | 1105520   | 1105518   |  -2  |  0.00% | 0.00% |
| instcount.TotalInsts                       | 9795737   | 9795776   |  39  |  0.00% | 0.00% |
| simplifycfg.NumInvokes                     | 2784      | 2786      |   2  |  0.07% | 0.07% |
| simplifycfg.NumSimpl                       | 1001840   | 1001850   |  10  |  0.00% | 0.00% |
| simplifycfg.NumSinkCommonInstrs            | 15174     | 15170     |  -4  | -0.03% | 0.03% |
```

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D86306
2020-08-25 10:38:11 +03:00
Sanjay Patel 557b890ff4 [InstCombine] improve demanded element analysis for vector insert-of-extract
InstCombine currently has odd rules for folding insert-extract chains to shuffles,
so we miss collapsing seemingly simple cases as shown in the tests here.

But poison makes this not quite as easy as we might have guessed. Alive2 tests to
show the subtle difference (similar to the regression tests):
https://alive2.llvm.org/ce/z/hp4hv3 (this is ok)
https://alive2.llvm.org/ce/z/ehEWaN (poison leakage)

SLP tends to create these patterns (as shown in the SLP tests), and this could
help with solving PR16739.

Differential Revision: https://reviews.llvm.org/D86460
2020-08-24 17:00:16 -04:00
Bjorn Pettersson fce44ff5da [Scalarizer] Avoid updating the name of globals
The "takeName" logic at the end of ScalarizerVisitor::finish
could end up renaming global variables when having simplified
and extractelement instruction to simply pick a single vector
element. If the input vector to the extractelement instruction
held pointers to global variables we ended up renaming the global
variable.
The patch make sure we only take the name of the replaced Op when
we have added new instructions that might need a useful name.

Reviewed By: lebedev.ri

Differential Revision: https://reviews.llvm.org/D86472
2020-08-24 21:55:03 +02:00
Roman Lebedev 56c529300e
[NFC][InstCombine] Adjust naming for some methods to match coding standards
Requested as preparatory cleanup in https://reviews.llvm.org/D86306#inline-799065
2020-08-24 22:39:34 +03:00
Fangrui Song 44ee9d070a Revert D85812 "[coroutine] should disable inline before calling coro split"
This reverts commit 2e43acfed8.

LLVMCoroutines (the library which contains Coroutines.h) depends on LLVMipo (the
library which contains SampleProfile.cpp). It is inappropriate for
SampleProfile.cpp to depent on Coroutines.h (circular dependency).

The test inverted dependencies as well:
llvm/test/Transforms/Coroutines/coro-inline.ll uses -sample-profile.
2020-08-24 11:41:05 -07:00
Florian Hahn d1a1cce5b1 [DSE,MemorySSA] Do not use callCapturesBefore in isReadClobber.
Using callCapturesBefore potentially improves the precision and the
number of stores we can remove. But in practice, it seems to have very
little impact in terms of stores removed. For example, for
SPEC2000/SPEC2006/MultiSource with -O3 -flto, ~50 more stores are
removed (out of ~26900 stores removed). But in terms of compile-time, it
is very expensive and the patch gives substantial compile-time
improvements: Geomean O3 -0.24%, ReleaseThinLTO -0.47%, ReleaseLTO-g
-0.39%.

http://llvm-compile-time-tracker.com/compare.php?from=612a0bff88ed906c83b82f079d4c49e5fecfb9d0&to=e6c86b96d20d97dd88e903a409bd8d39b6114312&stat=instructions
2020-08-24 16:19:42 +01:00
dongAxis 2e43acfed8 [coroutine] should disable inline before calling coro split
summary:
When callee coroutine function is inlined into caller coroutine
function before coro-split pass, llvm will emits "coroutine should
have exactly one defining @llvm.coro.begin". It seems that coro-early
pass can not handle this quiet well.
So we believe that unsplited coroutine function should not be inlined.
This patch fix such issue by not inlining function if it has attribute
"coroutine.presplit" (it means the function has not been splited) to
fix this issue

TestPlan: check-llvm

Reviewed By: wenlei

Differential Revision: https://reviews.llvm.org/D85812
2020-08-24 22:22:08 +08:00
Francesco Petrogalli 5a34b3ab95 [llvm][LV] Replace `unsigned VF` with `ElementCount VF` [NFCI]
Changes:

* Change `ToVectorTy` to deal directly with `ElementCount` instances.
* `VF == 1` replaced with `VF.isScalar()`.
* `VF > 1` and `VF >=2` replaced with `VF.isVector()`.
* `VF <=1` is replaced with `VF.isZero() || VF.isScalar()`.
* Replaced the uses of `llvm::SmallSet<ElementCount, ...>` with
   `llvm::SmallSetVector<ElementCount, ...>`. This avoids the need of an
   ordering function for the `ElementCount` class.
* Bits and pieces around printing the `ElementCount` to string streams.

To guarantee that this change is a NFC, `VF.Min` and asserts are used
in the following places:

1. When it doesn't make sense to deal with the scalable property, for
example:
   a. When computing unrolling factors.
   b. When shuffle masks are built for fixed width vector types
In this cases, an
assert(!VF.Scalable && "<mgs>") has been added to make sure we don't
enter coepaths that don't make sense for scalable vectors.
2. When there is a conscious decision to use `FixedVectorType`. These
uses of `FixedVectorType` will likely be removed in favour of
`VectorType` once the vectorizer is generic enough to deal with both
fixed vector types and scalable vector types.
3. When dealing with building constants out of the value of VF, for
example when computing the vectorization `step`, or building vectors
of indices. These operation _make sense_ for scalable vectors too,
but changing the code in these places to be generic and make it work
for scalable vectors is to be submitted in a separate patch, as it is
a functional change.
4. When building the potential VFs in VPlan. Making the VPlan generic
enough to handle scalable vectorization factors is a functional change
that needs a separate patch. See for example `void
LoopVectorizationPlanner::buildVPlans(unsigned MinVF, unsigned
MaxVF)`.
5. The class `IntrinsicCostAttribute`: this class still uses `unsigned
VF` as updating the field to use `ElementCount` woudl require changes
that could result in changing the behavior of the compiler. Will be done
in a separate patch.
7. When dealing with user input for forcing the vectorization
factor. In this case, adding support for scalable vectorization is a
functional change that migh require changes at command line.

Note that in some places the idiom

```
unsigned VF = ...
auto VTy = FixedVectorType::get(ScalarTy, VF)
```

has been replaced with

```
ElementCount VF = ...
assert(!VF.Scalable && ...);
auto VTy = VectorType::get(ScalarTy, VF)
```

The assertion guarantees that the new code is (at least in debug mode)
functionally equivalent to the old version. Notice that this change had been
possible because none of the methods that are specific to `FixedVectorType`
were used after the instantiation of `VTy`.

Reviewed By: rengolin, ctetreau

Differential Revision: https://reviews.llvm.org/D85794
2020-08-24 13:54:03 +00:00
Francesco Petrogalli bad7d6b373 Revert "[llvm][LV] Replace `unsigned VF` with `ElementCount VF` [NFCI]"
Reverting because the commit message doesn't reflect the one agreed on
phabricator at https://reviews.llvm.org/D85794.

This reverts commit c8d2b065b9.
2020-08-24 13:50:55 +00:00
Francesco Petrogalli c8d2b065b9 [llvm][LV] Replace `unsigned VF` with `ElementCount VF` [NFCI]
Changes:

* Change `ToVectorTy` to deal directly with `ElementCount` instances.
* `VF == 1` replaced with `VF.isScalar()`.
* `VF > 1` and `VF >=2` replaced with `VF.isVector()`.
* `VF <=1` is replaced with `VF.isZero() || VF.isScalar()`.
* Add `<` operator to `ElementCount` to be able to use
`llvm::SmallSetVector<ElementCount, ...>`.
* Bits and pieces around printing the ElementCount to string streams.
* Added a static method to `ElementCount` to represent a scalar.

To guarantee that this change is a NFC, `VF.Min` and asserts are used
in the following places:

1. When it doesn't make sense to deal with the scalable property, for
example:
   a. When computing unrolling factors.
   b. When shuffle masks are built for fixed width vector types
In this cases, an
assert(!VF.Scalable && "<mgs>") has been added to make sure we don't
enter coepaths that don't make sense for scalable vectors.
2. When there is a conscious decision to use `FixedVectorType`. These
uses of `FixedVectorType` will likely be removed in favour of
`VectorType` once the vectorizer is generic enough to deal with both
fixed vector types and scalable vector types.
3. When dealing with building constants out of the value of VF, for
example when computing the vectorization `step`, or building vectors
of indices. These operation _make sense_ for scalable vectors too,
but changing the code in these places to be generic and make it work
for scalable vectors is to be submitted in a separate patch, as it is
a functional change.
4. When building the potential VFs in VPlan. Making the VPlan generic
enough to handle scalable vectorization factors is a functional change
that needs a separate patch. See for example `void
LoopVectorizationPlanner::buildVPlans(unsigned MinVF, unsigned
MaxVF)`.
5. The class `IntrinsicCostAttribute`: this class still uses `unsigned
VF` as updating the field to use `ElementCount` woudl require changes
that could result in changing the behavior of the compiler. Will be done
in a separate patch.
7. When dealing with user input for forcing the vectorization
factor. In this case, adding support for scalable vectorization is a
functional change that migh require changes at command line.

Differential Revision: https://reviews.llvm.org/D85794
2020-08-24 13:39:42 +00:00
Florian Hahn b99a5eb659 [DSE,MemorySSA] Delay PointerMayBeCaptured calls until actually needed.
Avoid computing InvisibleToCallerBefore/AfterRet up front. In most
cases, this information is not really needed. Instead, introduce helper
functions to compute and cache the result on demand.

Notably, this also does not use PointerMayBeCapturedBefore for
isInvisibleToCallerBeforeRet, as it requires the killing MemoryDef as
starting instruction, making the caching ineffective. But it appears the
use of PointerMayBeCapturedBefore has very limited benefits in practice
(e.g. on SPEC2000/SPEC2006/MultiSource there are no binary changes with
-O3 -flto). Refrain from using it for now, to limit-compile-time.

This gives some nice compile-time improvements:
http://llvm-compile-time-tracker.com/compare.php?from=db9345f6810f379a36752dc52caf5230585d0ebd&to=b4d091047e1b8a3d377d200137b79d03aca65663&stat=instructions
2020-08-24 14:05:44 +01:00
Florian Hahn 2431b143ae [DSE,MemorySSA] Limit elimination at end of function to single UO.
Limit elimination of stores at the end of a function to MemoryDefs with
a single underlying object, to save compile time.

In practice, the case with multiple underlying objects seems not very
important in practice. For -O3 -flto on MultiSource/SPEC2000/SPEC2006
this results in a total of 2 more stores being eliminated.

We can always re-visit that in the future.
2020-08-24 13:00:17 +01:00
Sanjay Patel 6a44edb8da [InstCombine] fold abs of select with negated op (PR39474)
Similar to the existing transform - peek through a select
to match a value and its negation.

https://alive2.llvm.org/ce/z/MXi5KG

  define i8 @src(i1 %b, i8 %x) {
  %0:
    %neg = sub i8 0, %x
    %sel = select i1 %b, i8 %x, i8 %neg
    %abs = abs i8 %sel, 1
    ret i8 %abs
  }
  =>
  define i8 @tgt(i1 %b, i8 %x) {
  %0:
    %abs = abs i8 %x, 1
    ret i8 %abs
  }
  Transformation seems to be correct!
2020-08-24 07:37:55 -04:00
Sam Parker 8ce450da32 [NFCI][SimplifyCFG] Combine select costs and checks
Combine the cost modelling and validity checks for the phi to select
conversion in SpeculativelyExecuteBB, extracting the logic out into
a function.
2020-08-24 09:16:11 +01:00
Roman Lebedev f6decfa36d
[InstCombine] Negator: freeze is freely negatible if it's operand is negatible 2020-08-23 23:28:19 +03:00
Florian Hahn 2843c9fe0a [DSE,MemorySSA] Keep single DL instance in DSEState (NFC).
Small cleanup, also removes one instance of getting DataLayout without
using it later.
2020-08-23 15:56:38 +01:00
Sanjay Patel ec06b38130 [InstCombine] canonicalize 'not' ops before logical shifts
This reverses the existing transform that would uniformly canonicalize any 'xor' after any shift. In the case of logical shifts, that turns a 'not' into an arbitrary 'xor' with constant, and that's probably not as good for analysis, SCEV, or codegen.

The SCEV motivating case is discussed in:
http://bugs.llvm.org/PR47136

There's an analysis motivating case at:
http://bugs.llvm.org/PR38781

I did draft a patch that would do the same for 'ashr' but that's questionable because it's just swapping the position of a 'not' and uncovers at least 2 missing folds that we would probably need to deal with as preliminary steps.

Alive proofs:
https://rise4fun.com/Alive/BBV

  Name: shift right of 'not'
  Pre: C2 == (-1 u>> C1)
  %a = lshr i8 %x, C1
  %r = xor i8 %a, C2
  =>
  %n = xor i8 %x, -1
  %r = lshr i8 %n, C1

  Name: shift left of 'not'
  Pre: C2 == (-1 << C1)
  %a = shl i8 %x, C1
  %r = xor i8 %a, C2
  =>
  %n = xor i8 %x, -1
  %r = shl i8 %n, C1

  Name: ashr of 'not'
  %a = ashr i8 %x, C1
  %r = xor i8 %a, -1
  =>
  %n = xor i8 %x, -1
  %r = ashr i8 %n, C1

Differential Revision: https://reviews.llvm.org/D86243
2020-08-22 09:38:13 -04:00
Florian Hahn 5e7e2162d4 [DSE,MemorySSA] Use BatchAA for AA queries.
We can use BatchAA to avoid some repeated AA queries. We only remove
stores, so I think we will get away with using a single BatchAA instance
for the complete run.

The changes in AliasAnalysis.h mirror the changes in D85583.

The change improves compile-time by roughly 1%.
http://llvm-compile-time-tracker.com/compare.php?from=67ad786353dfcc7633c65de11601d7823746378e&to=10529e5b43809808e8c198f88fffd8f756554e45&stat=instructions

This is part of the patches to bring down compile-time to the level
referenced in
http://lists.llvm.org/pipermail/llvm-dev/2020-August/144417.html

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D86275
2020-08-22 08:36:35 +01:00
Roman Lebedev 503deec218
Temporairly revert "[SimplifyCFG][LoopRotate] SimplifyCFG: disable common instruction hoisting by default, enable late in pipeline"
As disscussed in post-commit review starting with
	https://reviews.llvm.org/D84108#2227365
while this appears to be mostly a win overall, especially code-size-wise,
this appears to shake //certain// code pattens in a way that is extremely
unfavorable for performance (+30% runtime regression)
on certain CPU's (i personally can't reproduce).

So until the behaviour is better understood, and a path forward is mapped,
let's back this out for now.

This reverts commit 1d51dc38d8.
2020-08-22 00:33:22 +03:00
kuterd 65fcc0ee31 [Attributor] Function seed allow list
-  Adds a command line option to seed only selected functions.
  - Makes seed allow listing exclusive to assertions enabled builds.

Reviewed By: sstefan1

Differential Revision: https://reviews.llvm.org/D86129
2020-08-21 23:55:26 +03:00
Shinji Okumura e21a22a7a8 [Attributor] fix AANoUndef initialization
Currently, `AANoUndefImpl::initialize` mistakenly always indicates optimistic fixpoint for function returned position.
 This is because an associated value is `Function` in the case, and `isGuaranteedNotToBeUndefOrPoison` returns true for Function.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D86361
2020-08-22 05:06:14 +09:00
Amy Huang 5e3fd471ac [Cloning] Fix to cloning DISubprograms.
When trying to enable -debug-info-kind=constructor there was an assert
that occurs during debug info cloning ("mismatched subprogram between
llvm.dbg.value variable and !dbg attachment").
It appears that during llvm::CloneFunctionInto, a DISubprogram could be
duplicated when MapMetadata is called, and then added to the MD map again
when DIFinder gets a list of subprograms. This results in two different
versions of the DISubprogram.

This patch switches the order so that the DIFinder subprograms are
added before MapMetadata is called.

Fixes https://bugs.llvm.org/show_bug.cgi?id=46784

Differential Revision: https://reviews.llvm.org/D86185
2020-08-21 11:54:56 -07:00
Serguei Katkov 9e362bb0eb [InstCombine] Remove unused entries in gc-live bundle of statepoint
If some of gc live value are not used in gc.relocate we can remove them
from gc-live bundle of statepoint instruction.

Also the CL removes duplicated Values in gc-live bundle.

Reviewers: reames, dantrushin
Reviewed By: dantrushin
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D85959
2020-08-22 01:36:22 +07:00
Serguei Katkov 63d9d56a55 [InstCombine] Move handling of gc.relocate in a gc.statepoint
The only def for gc.relocate is a gc.statepoint. But real dependency is not
described by def-use chain. Instead this dependency is encoded by indecies
of operands in gc-live bundle of statepoint as integer constants in gc.relocate.

InstCombine operates by def-use chain. As a result when value in gc-live bundle
is simplified the gc.statepoint itself is not simplified but it might simplify dependent
gc.relocates. To trigger the optimization of gc.relocate we now unconditionally trigger
check of all dependent gc.relocates by adding them to worklist.

This CL handles of gc.relocates as process of gc.statepoint optimization considering
gc.statepoint and related gc.relocate as whole entity.

Reviewers: reames, dantrushin
Reviewed By: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D85954
2020-08-21 23:44:23 +07:00
Florian Hahn 8eded24bf4 Recommit "[SCEVExpander] Add helper to clean up instrs inserted while expanding."
Recommit the patch after fixing an issue reported caused by the fact
that re-used values are also added to InsertedValues.

Additional tests have been added in 88818491b9

This reverts the revert commit 38884641f2.
2020-08-21 15:04:17 +01:00
Sam Parker bfc6d8b59b [NFC][SimplifyCFG] Formatting and variable rename 2020-08-21 13:11:17 +01:00
Florian Hahn 9f7350672e [DSE,MemorySSA] Handle atomicrmw/cmpxchg conservatively.
This adds conservative handling of AtomicRMW/AtomicCmpXChg to
isDSEBarrier, similar to atomic loads and stores.
2020-08-21 10:42:42 +01:00
Yevgeny Rouban 18bc400f97 [NewPM][PassInstrumentation] Add PreservedAnalyses parameter to AfterPass* callbacks
Both AfterPass and AfterPassInvalidated pass instrumentation
callbacks get additional parameter of type PreservedAnalyses.
This patch was created by @fedor.sergeev. I have just slightly
changed it.

Reviewers: fedor.sergeev

Differential Revision: https://reviews.llvm.org/D81555
2020-08-21 16:10:42 +07:00
Sam Parker 47251582f5 [SimplifyCFG] Cost required selects
Before we speculatively execute a basic block, query the cost of
inserting the necessary select instructions against the phi folding
threshold. For non-trivial insertions, a more accurate decision can
probably be made during machine if-conversion. With minsize we query
the CodeSize cost, otherwise we use SizeAndLatency.

Differential Revision: https://reviews.llvm.org/D82438
2020-08-21 09:52:52 +01:00
Florian Hahn a0e92ffd0d [DSE,MemorySSA] Split off partial tracking from isOverwite.
When traversing memory uses to look for aliasing reads/writes, we only
care about complete overwrites. This patch splits off the partial
overwrite tracking from isOverwrite This avoids some unnecessary work
when checking for read/write clobbers with MemorySSA-DSE.
isOverwrite, which skips the partial overwrite tracking.

This gives a relatively small improvement
http://llvm-compile-time-tracker.com/compare.php?from=ef2a2f77f87553a0a4a39f518eb9ac86b756bda6&to=658f3905dd96d3415f3782adc712c79fa59a4665&stat=instructions

This is part of the patches to bring down compile-time to the level
referenced in
http://lists.llvm.org/pipermail/llvm-dev/2020-August/144417.html

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D86280
2020-08-21 09:13:59 +01:00
David Green 2b69efded0 [ARM][LV] Add a preferPredicatedReductionSelect target hook
As part of D84741, this adds a target hook for the
preferPredicatedReductionSelect option and makes use
of it under MVE, allowing us to tail predicate most
reduction loops.

Differential Revision: https://reviews.llvm.org/D85980
2020-08-21 08:48:12 +01:00
David Green 816097e4e5 [LV] Allow tail folded reduction selects to remain in the loop
The normal scheme for tail folding reductions is to use:

loop:
  p = phi(0, a)
  mask = ...
  x = masked_load(..., mask)
  a = add(x, p)
s = select(mask, a, p)

This means we need to keep the register p and a alive out of the loop, plus
the mask. On a target with predicated operations we can instead generate
the phi as p = phi(0, s). This ensures the select in the loop and we can
fold select(m, add(a, b), c) to something like a vaddt c, a, b using the
m predicate. This in turn allows us to tail predicate the entire loop.

Differential Revision: https://reviews.llvm.org/D84741
2020-08-20 14:31:14 +01:00
Shinji Okumura 835cfa5def [Attributor] Handle CallBase case in AAValueConstantRange::initialize
Currently, although we handle `CallBase` case in updateImpl, we give up in initialize in the case.
That is problematic when we propagate a range from call site returned position to floating position.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D86196
2020-08-20 20:15:19 +09:00
David Stenberg 8206257cb8 [GlobalOpt] Fix an incorrect Modified status
When removing a non-constant store to a global in
CleanupPointerRootUsers(), the GlobalOpt pass could incorrectly return
false.

This was caught using the check introduced by D80916.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D86149
2020-08-20 11:52:09 +02:00
David Stenberg 7a1029fd1e Reland "[LoopUnswitch] Fix incorrect Modified status"
Relanded since the buildbot issue was unrelated to this commit.

When hoisting simple values out from a loop, and an optsize attribute, a
convergent call, or an invoke instruction hindered the pass from
unswitching the loop, the pass would return an incorrect Modified
status.

This was caught using the check introduced by D80916.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D86085
2020-08-20 11:52:09 +02:00
David Stenberg ca688ae497 Revert "[LoopUnswitch] Fix incorrect Modified status"
This reverts commit dfd447c220.

After I pushed this commit, llvm-sphinx-docs started failing, due to:

  Warning, treated as error:
  extension 'recommonmark' has no setup() function;
  is it really a Sphinx extension module?

I don't see how this commit may have caused that, but I'm still
reverting it since I don't know how to proceed with that
troubleshooting.
2020-08-20 11:14:23 +02:00
Evgeny Leviant d5b701b972 [ThinLTO] Import globals recursively
Differential revision: https://reviews.llvm.org/D73698
2020-08-20 12:13:43 +03:00
David Stenberg dfd447c220 [LoopUnswitch] Fix incorrect Modified status
When hoisting simple values out from a loop, and an optsize attribute, a
convergent call, or an invoke instruction hindered the pass from
unswitching the loop, the pass would return an incorrect Modified
status.

This was caught using the check introduced by D80916.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D86085
2020-08-20 09:04:16 +02:00
Johannes Doerfert 012819f301 [Attributor][FIX] Update the call graph properly when internalizing functions
The internal version is now part of the SCC, make sure to perform this
update.
2020-08-20 01:44:58 -05:00
Johannes Doerfert 3edea15f9a [Attributor] Simplify comparison against constant null pointer
Comparison against null is a common pattern that usually is followed by
error handling code and the likes. We now use AANonNull to simplify
these comparisons optimistically in order to make more code dead early
on.

Reviewed By: uenoku

Differential Revision: https://reviews.llvm.org/D86145
2020-08-20 01:44:58 -05:00
Johannes Doerfert d01ad217ba [Attributor][FIX] Do not use cyclic arguments for `nonnull`
`AADereferenceable::getAssumedDereferenceableBytes()` is actually
deducing `dereferenceable_or_null`. We should not use that information
to deduce `nonnull`, since it doesn't imply `nonnull`.
2020-08-20 01:44:58 -05:00
Johannes Doerfert a49dae0e38 [Attributor][AAIsDead][NFC] Skip uninteresting instructions early 2020-08-20 01:44:58 -05:00
Johannes Doerfert 08f33756e6 [Attributor][NFC] Extract functionality into own member 2020-08-20 01:44:58 -05:00
Johannes Doerfert 1de70a724e Revert "[OpenMPOpt] ICV tracking for calls"
This commits breaks certain OpenMP codes (on power) because it expanded
the Attributor scope without telling the Attributor about the SCC
extend. See: https://reviews.llvm.org/D85544#2227611

This reverts commit b0b32e6490.
2020-08-20 00:00:35 -05:00
Kyungwoo Lee 7a028fe702 Force Remove Attribute
-force-attribute adds an attribute to function via command-line.
However, there was no counter-part to remove an attribute.  This patch
adds -force-remove-attribute that removes an attribute from function.

Differential Revision: https://reviews.llvm.org/D85586
2020-08-19 17:30:13 -04:00
Sanjay Patel 6f3511a01a [ValueTracking] define/use max recursion depth in header
There's a potential motivating case to increase this limit in PR47191:
http://bugs.llvm.org/PR47191

But first we should make it less hacky. The limit in InstCombine is directly tied
to this value because an increase there can cause asserts in the underlying value
tracking calls if not changed together. The usage in VectorUtils is independent,
but the comment suggests that we should use the same value unless there's a known
reason to diverge. There are similar limits in codegen analysis, but I think we
should leave those independent in case we intentionally want the optimization
power/cost to be different there.

Differential Revision: https://reviews.llvm.org/D86113
2020-08-19 16:56:59 -04:00
Hiroshi Yamauchi ab401a8c8a [PGO][PGSO][LV] Fix loop not vectorized issue under profile guided size opts.
D81345 appears to accidentally disables vectorization when explicitly
enabled. As PGSO isn't currently accessible from LoopAccessInfo, revert back to
the vectorization with versioning-for-unit-stride for PGSO.

Differential Revision: https://reviews.llvm.org/D85784
2020-08-19 12:13:34 -07:00
Florian Hahn c0cbe6453a [DSE] Remove dead argument from removePartiallyOverlappedStores (NFC).
The argument is unused and can be removed.
2020-08-19 19:33:52 +01:00
Mehdi Amini a407ec9b6d Revert "Revert "[NFC][llvm] Make the contructors of `ElementCount` private.""
Was reverted because MLIR/Flang builds were broken, these APIs have been
fixed in the meantime.
2020-08-19 17:26:36 +00:00
Mehdi Amini 4fc56d70aa Revert "[NFC][llvm] Make the contructors of `ElementCount` private."
This reverts commit 264afb9e6a.
(and dependent 6b742cc48 and fc53bd610f)

MLIR/Flang are broken.
2020-08-19 17:21:37 +00:00
Hamilton Tobon Mosquera bd2fa1819b [OpenMPOpt][HideMemTransfersLatency] Moving the 'wait' counterpart of __tgt_target_data_begin_mapper
canBeMovedDownwards checks if the "wait" counterpart of __tgt_target_data_begin_mapper can be moved downwards, returning a pointer to the instruction that might require/modify the data transferred, and returning null it the movement is not possible or not worth it. The function splitTargetDataBeginRTC receives that returned instruction and instead of moving the "wait" it creates it at that point.

Differential Revision: https://reviews.llvm.org/D86155
2020-08-19 11:42:22 -05:00
Francesco Petrogalli 264afb9e6a [NFC][llvm] Make the contructors of `ElementCount` private.
Differential Revision: https://reviews.llvm.org/D86120
2020-08-19 16:26:44 +00:00
Sanjay Patel c8d711adae [InstCombine] reduce code duplication; NFC 2020-08-19 12:05:12 -04:00
Benjamin Kramer b98e25b6d7 Make helpers static. NFC. 2020-08-19 16:00:03 +02:00
Roman Lebedev 3d76a133c7
Revert "[InstCombine] Lower infinite combine loop detection thresholds"
And as being reported by Florian Hahn, there's a hit
in MultiSource/Benchmarks/mafft from the test-suite on X86 with -O3 -flto,
so reverting until addressed.

This reverts commit 71e0b82c9f.
2020-08-19 16:53:30 +03:00
Roman Lebedev 71e0b82c9f
[InstCombine] Lower infinite combine loop detection thresholds
It's been a month since 2f3862eb9f,
and no new bug reports about the threshold were filled,
so let's bump it again and wait again.
2020-08-19 14:37:57 +03:00
sstefan1 b0b32e6490 [OpenMPOpt] ICV tracking for calls
Introduce two new AAs. AAICVTrackerFunctionReturned which checks if a
function can have a unique ICV value after it is finished, and
AAICVCallSiteReturned which checks AAICVTrackerFunctionReturned for a
call site. This enables us to check the value of a call and if it
changes the ICV. This also changes the approach in
`getReplacementValues()` to a worklist-based approach so we can explore
all relevant BBs.

Differential Revision: https://reviews.llvm.org/D85544
2020-08-19 11:43:12 +02:00
Florian Hahn 1a55fbceaa [DSE,MemorySSA] Use NumRedundantStores instead of NumNoopStores.
Legacy DSE uses NumRedundantStores, while MemorySSA DSE uses
NumNoopStores. We should just use the same counter.
2020-08-19 08:50:33 +01:00
Roman Lebedev 2f01785857
[NFC][InstCombine] Aggregate reconstruction: use plain map
Now that we no longer require for this map to have stable iteration order,
we no longer need to pay for keeping the iteration order stable,
so switch from `SmallMapVector` to `SmallDenseMap`.
2020-08-19 01:09:25 +03:00
Roman Lebedev 78bd4231bf
[InstCombine] PHI-aware aggregate reconstruction: properly handle duplicate predecessors
While it may seem like we can just "deduplicate" the case where
some basic block happens to be a predecessor more than once,
which happens for e.g. switches, that is not correct thing to do.
We must actually add a PHI operand for each predecessor.

This was initially reported to me by David Major
as a clang crash during gecko build for android.
2020-08-19 01:00:42 +03:00
Sanjay Patel 139da9c4d7 [InstCombine] fold fabs of select with negated operand
This is the FP example shown in:
https://bugs.llvm.org/PR39474
2020-08-18 09:23:07 -04:00
Shinji Okumura 5e361e2aa4 [Attributor] Deduce noundef attribute
This patch introduces a new abstract attribute `AANoUndef` which corresponds to `noundef` IR attribute and deduce them.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D85184
2020-08-18 18:05:54 +09:00
Johannes Doerfert 8abd69aa9e [Attributor] Bail early if AAMemoryLocation cannot derive anything
Before this change we looked through all memory operations in a function
even if the first was an unknown call that could do anything. This did
cost a lot of time but there is little use to do so. We also avoid
creating AAs for things that we would have looked at in case no other AA
will; that is the reason for the test changes.

Running only the attributor-cgscc pass on a IR version of
`llvm-test-suite/MultiSource/Applications/SPASS/clause.c` reduced the
time we spend in `AAMemoryLocation::update` from 4% total to
0.9% (disclaimer: no accurate measurements).
2020-08-17 23:36:36 -05:00
Johannes Doerfert 1d99c3d707 [Attributor] We (should) keep the CG updated so we can mark it as preserved 2020-08-17 23:36:36 -05:00
Johannes Doerfert 858c75f7d1 [Attributor][NFC] Directly return proper type to avoid casts 2020-08-17 23:36:36 -05:00
Johannes Doerfert b27bdf955a [Attributor][FIX] Handle function pointers properly in AANonNull
Before we tired to create a dominator tree for a declaration when we
wanted to determine if the function pointer is `nonnull`. We now avoid
looking at global values if `Value::getPointerDereferenceableBytes` not
already determined `nonnull`.
2020-08-17 23:36:35 -05:00
Hamilton Tobon Mosquera 496f8e5b36 [OpenMPOpt][HideMemTransfersLatency] Split __tgt_target_data_begin_mapper into its "issue" and "wait" counterparts.
WIP that tries to hide the latency of runtime calls that involve host to
device memory transfers by splitting them into their "issue" and "wait"
versions. The "issue" is moved upwards as much as possible. The "wait" is
moved downards as much as possible. The "issue" issues the memory transfer
asynchronously, returning a handle. The "wait" waits in the returned
handle for the memory transfer to finish. We still lack of the movement.
2020-08-17 20:56:10 -05:00
Aditya Kumar 370330f084 NFC: [GVNHoist] Outline functions from the class
Reviewers: sebpop
Reviewed By: hiraditya

Differential Revision: https://reviews.llvm.org/D86032
2020-08-17 17:40:04 -07:00
Johannes Doerfert 19bd4ef157 [Attributor] Properly use the call site argument position 2020-08-17 18:21:09 -05:00
Johannes Doerfert 5dfc207c53 [Attributor][FIX] Do not request an AANonNull for non-pointer types 2020-08-17 18:21:08 -05:00
Roman Lebedev 03127f795b
[InstCombine] PHI-aware aggregate reconstruction: correctly detect "use" basic block
While the original implementation added in D85787 / ae7f08812e
is not incorrect, it is known to be suboptimal.

In particular, it is not incorrect to use the basic block
in which the original `insertvalue` instruction is located
as the merge point, that is not necessarily optimal,
as `@test6` shows.

We should look at all the AggElts, and, if they are all defined
in the same basic block, then that is the basic block we should use.

On RawSpeed library, this catches +4% (+50) more cases.
On vanilla LLVM test-suits, this catches +12% (+92) more cases.
2020-08-18 00:45:18 +03:00
Roman Lebedev f4f673e0e3
[NFC][InstCombine] PHI-aware aggregate reconstruction: don't capture UseBB in lambdas, take it as argument
In a following patch, UseBB will be detected later,
so capturing it is potentially error-prone (capture by ref vs by val).

Also, parametrized UseBB will likely be needed
for multiple levels of PHI indirections later on anyways.
2020-08-18 00:45:18 +03:00
Roman Lebedev 4973ca3eac
[NFC][InstCombine] PHI-aware aggregate reconstruction: insert PHI node manually
This is NFC at the moment, because right now we always insert the PHI
into the same basic block in which the original `insertvalue` instruction
is, but that will change.

Also, fixes addition of the suffix to the value names.
2020-08-18 00:45:17 +03:00
Florian Hahn 4cc20aa743 [DSE,MemorySSA] Skip access already dominated by a killing def.
If we already found a killing def (= a def that completely overwrites
the location) that dominates an access, we can skip processing it
further.

This does not help with compile-time, but increases the number of memory
accesses we can process with the same scan budget, leading to more
stores being eliminated.

Improvements with this change

Same hash: 203 (filtered out)
Remaining: 34
Metric: dse.NumFastStores

Program                                        base    dom     diff
 test-suite...rolangs-C++/family/family.test     2.00    4.00  100.0%
 test-suite...ProxyApps-C++/CLAMR/CLAMR.test   172.00  229.00  33.1%
 test-suite...ks/Prolangs-C/agrep/agrep.test    10.00   12.00  20.0%
 test-suite...oxyApps-C++/miniFE/miniFE.test    44.00   51.00  15.9%
 test-suite...marks/7zip/7zip-benchmark.test   1285.00 1474.00 14.7%
 test-suite...006/450.soplex/450.soplex.test   254.00  289.00  13.8%
 test-suite...006/447.dealII/447.dealII.test   2466.00 2798.00 13.5%
 test-suite...000/197.parser/197.parser.test     9.00   10.00  11.1%
 test-suite.../Benchmarks/nbench/nbench.test    85.00   91.00   7.1%
 test-suite...ce/Applications/siod/siod.test    68.00   72.00   5.9%
 test-suite...ications/JM/lencod/lencod.test   786.00  824.00   4.8%
 test-suite...6/464.h264ref/464.h264ref.test   765.00  798.00   4.3%
 test-suite.../Benchmarks/Ptrdist/bc/bc.test   105.00  109.00   3.8%
 test-suite...lications/obsequi/Obsequi.test    29.00   28.00  -3.4%
 test-suite...3.xalancbmk/483.xalancbmk.test   1322.00 1367.00  3.4%
 test-suite...chmarks/MallocBench/gs/gs.test   118.00  122.00   3.4%
 test-suite...T2006/401.bzip2/401.bzip2.test    60.00   62.00   3.3%
 test-suite...6/482.sphinx3/482.sphinx3.test    30.00   31.00   3.3%
 test-suite...rks/tramp3d-v4/tramp3d-v4.test   862.00  887.00   2.9%
 test-suite...telecomm-gsm/telecomm-gsm.test    78.00   80.00   2.6%
 test-suite...ediabench/gsm/toast/toast.test    78.00   80.00   2.6%
 test-suite.../Applications/SPASS/SPASS.test   163.00  167.00   2.5%
 test-suite...lications/ClamAV/clamscan.test   240.00  245.00   2.1%
 test-suite...006/453.povray/453.povray.test   1392.00 1419.00  1.9%
 test-suite...000/255.vortex/255.vortex.test   211.00  215.00   1.9%
 test-suite...:: External/Povray/povray.test   1295.00 1317.00  1.7%
 test-suite...lications/sqlite3/sqlite3.test   175.00  177.00   1.1%
 test-suite...T2000/256.bzip2/256.bzip2.test    99.00  100.00   1.0%
 test-suite...0/253.perlbmk/253.perlbmk.test   629.00  635.00   1.0%
 test-suite.../CINT2006/403.gcc/403.gcc.test   1183.00 1194.00  0.9%
 test-suite.../CINT2000/176.gcc/176.gcc.test   647.00  653.00   0.9%
 test-suite...ications/JM/ldecod/ldecod.test   512.00  516.00   0.8%
 test-suite...0.perlbench/400.perlbench.test   1026.00 1034.00  0.8%
 test-suite...-typeset/consumer-typeset.test   1876.00 1877.00  0.1%
 Geomean difference                                             7.3%
2020-08-17 20:54:48 +01:00
Florian Hahn df4756ec6c [DSE,MemorySSA] Check for underlying objects first.
isWriteAtEndOfFunction needs to check all memory uses of Def, which is
much more expensive than getting the underlying objects in practice.
Switch the call order, as recommended by the TODO, which was added as
per an earlier review.

This shaves off a bit of compile-time.
2020-08-17 18:52:18 +01:00
Florian Hahn 139810449b [DSE,MemorySSA] Account for ScanLimit == 0 on entry.
Currently the code does not account for the fact that getDomMemoryDef
can be called with ScanLimit == 0, if we reached the limit while
processing an earlier access. Also tighten the check a bit more and bump
the scan limit now that it is handled properly.

In some cases, this brings a 2x speedup in terms of compile-time.
2020-08-17 17:55:14 +01:00
Aditya Kumar cb6e6936db NFC: [GVNHoist] Hoist loop invariant code and rename variables for readability
Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D86031
2020-08-17 09:43:34 -07:00
Sanjay Patel e6b6787d01 [InstCombine] fold abs(X)/X to cmp+select
The backend can convert the select-of-constants to
bit-hack shift+logic if desirable.

https://alive2.llvm.org/ce/z/pgJT6E

  define i8 @src(i8 %x) {
  %0:
    %a = abs i8 %x, 1
    %d = sdiv i8 %x, %a
    ret i8 %d
  }
  =>
  define i8 @tgt(i8 %x) {
  %0:
    %cond = icmp sgt i8 %x, 255
    %r = select i1 %cond, i8 1, i8 255
    ret i8 %r
  }
  Transformation seems to be correct!
2020-08-17 08:01:28 -04:00
Sanjay Patel 6cd4a6f6b2 [InstCombine] reduce code duplication; NFC 2020-08-17 08:01:27 -04:00
Yonghong Song aa61e43040 [InstCombine] Fix a compilation bug
With gcc 6.3.0, I hit the following compilation bug.
  ../lib/Transforms/InstCombine/InstCombineVectorOps.cpp:937:2: error: extra ‘;’ [-Werror=pedantic]
   };
    ^
  cc1plus: all warnings being treated as errors

The error is introduced by Commit ae7f08812e ("[InstCombine]
Aggregate reconstruction simplification (PR47060)")
2020-08-16 21:56:42 -07:00
Roman Lebedev 0ec1f0f332
[NFCI][InstCombine] Pacify GCC builds - don't name variable and enum class identically 2020-08-16 23:37:36 +03:00
Roman Lebedev ae7f08812e
[InstCombine] Aggregate reconstruction simplification (PR47060)
This pattern happens in clang C++ exception lowering code, on unwind branch.
We end up having a `landingpad` block after each `invoke`, where RAII
cleanup is performed, and the elements of an aggregate `{i8*, i32}`
holding exception info are `extractvalue`'d, and we then branch to common block
that takes extracted `i8*` and `i32` elements (via `phi` nodes),
form a new aggregate, and finally `resume`'s the exception.

The problem is that, if the cleanup block is effectively empty,
it shouldn't be there, there shouldn't be that `landingpad` and `resume`,
said `invoke` should be a  `call`.

Indeed, we do that simplification in e.g. SimplifyCFG `SimplifyCFGOpt::simplifyResume()`.
But the thing is, all this extra `extractvalue` + `phi` + `insertvalue` cruft,
while it is pointless, does not look like "empty cleanup block".
So the `SimplifyCFGOpt::simplifyResume()` fails, and the exception is has
higher cost than it could have on unwind branch :S

This doesn't happen *that* often, but it will basically happen once per C++
function with complex CFG that called more than one other function
that isn't known to be `nounwind`.

I think, this is a missing fold in InstCombine, so i've implemented it.

I think, the algorithm/implementation is rather self-explanatory:
1. Find a chain of `insertvalue`'s that fully tell us the initializer of the aggregate.
2. For each element, try to find from which aggregate it was extracted.
   If it was extracted from the aggregate with identical type,
   from identical element index, great.
3. If all elements were found to have been extracted from the same aggregate,
   then we can just use said original source aggregate directly,
   instead of re-creating it.
4. If we fail to find said aggregate when looking only in the current block,
   we need be PHI-aware - we might have different source aggregate when coming
   from each predecessor.

I'm not sure if this already handles everything, and there are some FIXME's,
i'll deal with all that later in followups.

I'd be fine with going with post-commit review here code-wise,
but just in case there are thoughts, i'm posting this.

On RawSpeed, for example, this has the following effect:
```
| statistic name                                    | baseline | proposed |     Δ |       % | abs(%) |
|---------------------------------------------------|---------:|---------:|------:|--------:|-------:|
| instcombine.NumAggregateReconstructionsSimplified |        0 |     1253 |  1253 |   0.00% |  0.00% |
| simplifycfg.NumInvokes                            |      948 |     1355 |   407 |  42.93% | 42.93% |
| instcount.NumInsertValueInst                      |     4382 |     3210 | -1172 | -26.75% | 26.75% |
| simplifycfg.NumSinkCommonCode                     |      574 |      458 |  -116 | -20.21% | 20.21% |
| simplifycfg.NumSinkCommonInstrs                   |     1154 |      921 |  -233 | -20.19% | 20.19% |
| instcount.NumExtractValueInst                     |    29017 |    26397 | -2620 |  -9.03% |  9.03% |
| instcombine.NumDeadInst                           |   166618 |   174705 |  8087 |   4.85% |  4.85% |
| instcount.NumPHIInst                              |    51526 |    50678 |  -848 |  -1.65% |  1.65% |
| instcount.NumLandingPadInst                       |    20865 |    20609 |  -256 |  -1.23% |  1.23% |
| instcount.NumInvokeInst                           |    34023 |    33675 |  -348 |  -1.02% |  1.02% |
| simplifycfg.NumSimpl                              |   113634 |   114708 |  1074 |   0.95% |  0.95% |
| instcombine.NumSunkInst                           |    15030 |    14930 |  -100 |  -0.67% |  0.67% |
| instcount.TotalBlocks                             |   219544 |   219024 |  -520 |  -0.24% |  0.24% |
| instcombine.NumCombined                           |   644562 |   645805 |  1243 |   0.19% |  0.19% |
| instcount.TotalInsts                              |  2139506 |  2135377 | -4129 |  -0.19% |  0.19% |
| instcount.NumBrInst                               |   156988 |   156821 |  -167 |  -0.11% |  0.11% |
| instcount.NumCallInst                             |  1206144 |  1207076 |   932 |   0.08% |  0.08% |
| instcount.NumResumeInst                           |     5193 |     5190 |    -3 |  -0.06% |  0.06% |
| asm-printer.EmittedInsts                          |   948580 |   948299 |  -281 |  -0.03% |  0.03% |
| instcount.TotalFuncs                              |    11509 |    11507 |    -2 |  -0.02% |  0.02% |
| inline.NumDeleted                                 |    97595 |    97597 |     2 |   0.00% |  0.00% |
| inline.NumInlined                                 |   210514 |   210522 |     8 |   0.00% |  0.00% |
```
So we manage to increase the amount of `invoke` -> `call` conversions in SimplifyCFG by almost a half,
and there is a very apparent decrease in instruction and basic block count.

On vanilla llvm-test-suite:
```
| statistic name                                    | baseline | proposed |     Δ |       % | abs(%) |
|---------------------------------------------------|---------:|---------:|------:|--------:|-------:|
| instcombine.NumAggregateReconstructionsSimplified |        0 |      744 |   744 |   0.00% |  0.00% |
| instcount.NumInsertValueInst                      |     2705 |     2053 |  -652 | -24.10% | 24.10% |
| simplifycfg.NumInvokes                            |     1212 |     1424 |   212 |  17.49% | 17.49% |
| instcount.NumExtractValueInst                     |    21681 |    20139 | -1542 |  -7.11% |  7.11% |
| simplifycfg.NumSinkCommonInstrs                   |    14575 |    14361 |  -214 |  -1.47% |  1.47% |
| simplifycfg.NumSinkCommonCode                     |     6815 |     6743 |   -72 |  -1.06% |  1.06% |
| instcount.NumLandingPadInst                       |    14851 |    14712 |  -139 |  -0.94% |  0.94% |
| instcount.NumInvokeInst                           |    27510 |    27332 |  -178 |  -0.65% |  0.65% |
| instcombine.NumDeadInst                           |  1438173 |  1443371 |  5198 |   0.36% |  0.36% |
| instcount.NumResumeInst                           |     2880 |     2872 |    -8 |  -0.28% |  0.28% |
| instcombine.NumSunkInst                           |    55187 |    55076 |  -111 |  -0.20% |  0.20% |
| instcount.NumPHIInst                              |   321366 |   320916 |  -450 |  -0.14% |  0.14% |
| instcount.TotalBlocks                             |   886816 |   886493 |  -323 |  -0.04% |  0.04% |
| instcount.TotalInsts                              |  7663845 |  7661108 | -2737 |  -0.04% |  0.04% |
| simplifycfg.NumSimpl                              |   886791 |   887171 |   380 |   0.04% |  0.04% |
| instcount.NumCallInst                             |   553552 |   553733 |   181 |   0.03% |  0.03% |
| instcombine.NumCombined                           |  3200512 |  3201202 |   690 |   0.02% |  0.02% |
| instcount.NumBrInst                               |   741794 |   741656 |  -138 |  -0.02% |  0.02% |
| simplifycfg.NumHoistCommonInstrs                  |    14443 |    14445 |     2 |   0.01% |  0.01% |
| asm-printer.EmittedInsts                          |  7978085 |  7977916 |  -169 |   0.00% |  0.00% |
| inline.NumDeleted                                 |    73188 |    73189 |     1 |   0.00% |  0.00% |
| inline.NumInlined                                 |   291959 |   291968 |     9 |   0.00% |  0.00% |
```
Roughly similar effect, less instructions and blocks total.

See also: rGe492f0e03b01a5e4ec4b6333abb02d303c3e479e.

Compile-time wise, this appears to be roughly geomean-neutral:
http://llvm-compile-time-tracker.com/compare.php?from=39617aaed95ac00957979bc1525598c1be80e85e&to=b59866cf30420da8f8e3ca239ed3bec577b23387&stat=instructions

And this is a win size-wize in general:
http://llvm-compile-time-tracker.com/compare.php?from=39617aaed95ac00957979bc1525598c1be80e85e&to=b59866cf30420da8f8e3ca239ed3bec577b23387&stat=size-text

See https://bugs.llvm.org/show_bug.cgi?id=47060

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D85787
2020-08-16 23:27:56 +03:00
Sanjay Patel 3ffb751f3d [InstCombine] fold copysign with fabs/fneg operand
We already get this in the backend, but we need to do
it in IR too to consistently get yet more copysign
transforms.
2020-08-16 08:53:47 -04:00
Sanjay Patel 3fed67b7e6 [InstCombine] reduce code duplication; NFC 2020-08-16 08:53:47 -04:00
Wenlei He 577e58bcc7 [InlineAdvisor] New inliner advisor to replay inlining from optimization remarks
This change added a new inline advisor that takes optimization remarks from previous inlining as input, and provides the decision as advice so current inlining can replay inline decisions of a different compilation. Dwarf inline stack with line and discriminator is used as anchor for call sites including call context. The change can be useful for Inliner tuning as it provides a channel to allow external input for tweaking inline decisions. Existing alternatives like alwaysinline attribute is per-function, not per-callsite. Per-callsite inline intrinsic can be another solution (not yet existing), but it's intrusive to implement and also does not differentiate call context.

A switch -sample-profile-inline-replay=<inline_remarks_file> is added to hook up the new inline advisor with SampleProfileLoader's inline decision for replay. Since SampleProfileLoader does top-down inlining, inline decision can be specialized for each call context, hence we should be able to replay inlining accurately. However with a bottom-up inliner like CGSCC inlining, the replay can be limited due to lack of specialization for different call context. Apart from that limitation, the new inline advisor can still be used by regular CGSCC inliner later if needed for tuning purpose.

This is a resubmit of https://reviews.llvm.org/D83743
2020-08-15 20:17:21 -07:00
Luofan Chen 266949b2bc [Attributor][NFC] Format code 2020-08-16 00:00:45 +08:00
Luofan Chen b7448a348b [Attributor][NFC] Use indexes instead of iterator
When adding elements when iterating, the iterator will become
valid, which could cause errors. This fixes the issue by using
indexes instead of iterator.
2020-08-15 23:09:46 +08:00
Luofan Chen 87a85f3d57 [Attributor] Use internalized version of non-exact functions
This patch internalize non-exact functions and replaces of their uses
with the internalized version. Doing this enables the analysis of
non-exact functions.

We can do this because some non-exact functions with the same name
whose linkage is `linkonce_odr` or `weak_odr` should have the same
semantics, so we can safely internalize and replace use of them (the
result of the other version of this function should be the same.).
Note that not all functions can be internalized, e.g., function with
`linkonce` or `weak` linkage.

For now when specified in commandline, we internalize all functions
that meet the requirements without calculating the cost of such
internalzation.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D84167
2020-08-15 20:23:38 +08:00
Dávid Bolvanský f134fc4f1b Reland "[SLC] sprintf(dst, "%s", str) -> strcpy(dst, str)" 2020-08-15 12:14:57 +02:00
Martin Storsjö 3e7403a134 Revert "[SLC] sprintf(dst, "%s", str) -> strcpy(dst, str)"
This reverts commit 6dbf0cfcf7.

That commit caused failed assertions, e.g. like this:

$ cat sprintf-strcpy.c
char *ptr; void func(void) { ptr += sprintf(ptr, "%s", ""); }

$ clang -c sprintf-strcpy.c -O2 -target x86_64-linux-gnu
clang: ../lib/IR/Value.cpp:473: void llvm::Value::doRAUW(llvm::Value*,
llvm::Value::ReplaceMetadataUses): Assertion `New->getType() ==
getType() && "replaceAllUses of value with new value of different
type!"' failed.
2020-08-15 09:35:11 +03:00
Dávid Bolvanský f62de7c9c7 [SLC] Transform strncpy(dst, "text", C) to memcpy(dst, "text\0\0\0", C) for C <= 128 only
Transformation creates big strings for big C values, so bail out for C > 128.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D86004
2020-08-15 01:53:32 +02:00
Gui Andrade 05e3ab41e4 [MSAN] Avoid dangling ActualFnStart when replacing instruction
This would be a problem if the entire instrumented function was a call
to
e.g. memcpy

Use FnPrologueEnd Instruction* instead of ActualFnStart BB*

Differential Revision: https://reviews.llvm.org/D86001
2020-08-14 23:50:38 +00:00
Christopher Tetreault 416a6a85b1 [SVE] Remove calls to VectorType::getNumElements from AggressiveInstCombine
Reviewed By: fpetrogalli

Differential Revision: https://reviews.llvm.org/D82218
2020-08-14 16:40:34 -07:00
Jordan Rupprecht 38884641f2 Temporarily revert "[SCEVExpander] Add helper to clean up instrs inserted while expanding."
This reverts commit 7829c33084. The assertion is triggering on some internal code. A reduced test case is in progress.
2020-08-14 14:52:37 -07:00
Dávid Bolvanský 6dbf0cfcf7 [SLC] sprintf(dst, "%s", str) -> strcpy(dst, str)
Transform sprintf(dst, "%s", str) -> strcpy(dst, str) if result is unused
Avoid sprintf(dest, "%s", str) -> llvm.memcpy(align 1 dest, align 1 str, strlen(str)+1) if optimizing for size.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D85963
2020-08-14 23:48:53 +02:00
Gui Andrade 36ebabc153 [MSAN] Convert ActualFnStart to be a particular Instruction *, not BB
This allows us to add addtional instrumentation before the function start,
without splitting the first BB.

Differential Revision: https://reviews.llvm.org/D85985
2020-08-14 21:43:56 +00:00
Gui Andrade 97de0188dd [MSAN] Reintroduce libatomic load/store instrumentation
Have the front-end use the `nounwind` attribute on atomic libcalls.
This prevents us from seeing `invoke __atomic_load` in MSAN, which
is problematic as it has no successor for instrumentation to be added.
2020-08-14 20:31:10 +00:00
Shinji Okumura 5f55a8193c [Attributor] Implement AAPotentialValues
This patch provides an implementation of `AAPotentialValues`.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D85632
2020-08-14 20:51:14 +09:00
Sam Parker 725400f993 [NFCI][SimpleLoopUnswitch] Adjust CostKind query
When getUserCost was transitioned to use an explicit CostKind,
TCK_CodeSize was used even though the original kind was implicitly
SizeAndLatency so restore this behaviour. We now only query for
CodeSize when optimising for minsize.

I expect this to not change anything as, I think all, targets will
currently return the same value for CodeSize and SizeLatency. Indeed
I see no changes in the test suite for Arm, AArch64 and X86.

Differential Revision: https://reviews.llvm.org/D85829
2020-08-14 07:54:20 +01:00
Arthur Eubanks 48cd5b72b1 Revert "[SLC] sprintf(dst, "%s", str) -> strcpy(dst, str)"
This reverts commit ab9fc8bae8.

Incorrect transformation if the result is used.
Causes breakages, e.g.
http://green.lab.llvm.org/green/job/test-suite-verify-machineinstrs-x86_64-O3/8193/
2020-08-13 21:05:03 -07:00
Peter Collingbourne c201f27225 hwasan: Emit the globals note even when globals are uninstrumented.
This lets us support the scenario where a binary is linked from a mix
of object files with both instrumented and non-instrumented globals.
This is likely to occur on Android where the decision of whether to use
instrumented globals is based on the API level, which is user-facing.

Previously, in this scenario, it was possible for the comdat from
one of the object files with non-instrumented globals to be selected,
and since this comdat did not contain the note it would mean that the
note would be missing in the linked binary and the globals' shadow
memory would be left uninitialized, leading to a tag mismatch failure
at runtime when accessing one of the instrumented globals.

It is harmless to include the note when targeting a runtime that does
not support instrumenting globals because it will just be ignored.

Differential Revision: https://reviews.llvm.org/D85871
2020-08-13 16:33:22 -07:00
Dávid Bolvanský ab9fc8bae8 [SLC] sprintf(dst, "%s", str) -> strcpy(dst, str)
Solves 46489
2020-08-14 00:05:55 +02:00
Dávid Bolvanský 5ef2287d36 [SLC] Optimize strncpy(a, a, C) to memcpy(a, a000, C)
Solves PR47154
2020-08-13 22:22:51 +02:00
Aditya Kumar 1a8c9cd1d9 Fix PR45442: Bail out when MemorySSA information is not available
Reviewers: sebpop, uabelho, fhahn
Reviewed by: fhahn

Differential Revision: https://reviews.llvm.org/D85881
2020-08-13 11:25:58 -07:00
Aditya Kumar 44716856db Fix PR45442: Bail out when MemorySSA information is not available 2020-08-13 09:31:18 -07:00
Bjorn Pettersson 11446b02c7 [VectorCombine] Fix for non-zero addrspace when creating vector load from scalar load
This is a fixup to commit 43bdac2906, to make sure the
address space from the original load pointer is retained in the
vector pointer.

Resolves problem with
  Assertion `castIsValid(op, S, Ty) && "Invalid cast!"' failed.
due to address space mismatch.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D85912
2020-08-13 18:25:32 +02:00
Serguei Katkov 98ba0a5ffe [InstCombine] Handle gc.relocate(null) in one iteration
InstCombine adds users of transformed instruction to working list to
process on the same iteration. However gc.relocate may have a hidden
user (next gc.relocate) which is connected through gc.statepoint intrinsic and
there is no direct def-use chain between them.

In this case if the next gc.relocation is already processed it will not be added
to worklist and will not be able to be processed on the same iteration.
Let's we have the following case:
A = gc.relocate(null)
B = statepoint(A)
C = gc.relocate(B, hidden(A))
If C is already considered then after replacement of A with null, statepoint B
instruction will be added to the queue but not C.
C can be processed only on the next iteration.

If the chain of relocation is pretty long the many iteration may be required.
This change is to reduce the number of iteration to meet the latest changes
related to reducing infinite loop threshold.

This is a quick (not best) fix. In the follow up patches I plan to move gc relocation
handling into statepoint handler. This should also help to remove unused gc live
entries in statepoint bundle.

Reviewers: reames, dantrushin
Reviewed By: reames
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D75598
2020-08-13 23:16:27 +07:00
David Stenberg e8ebebb0bd [InstCombine] Fix incorrect Modified status
When removing instructions from unreachable blocks, and only debug info
intrinsics were removed, InstCombine could incorrectly return a false
Modified status.

This is fixed by making removeAllNonTerminatorAndEHPadInstructions()
also return how many debug info intrinsics that were removed, and take
that into account.

This was caught using the check introduced by D80916.

Reviewed By: majnemer

Differential Revision: https://reviews.llvm.org/D85839
2020-08-13 15:10:41 +02:00
Florian Hahn 3b0878a370 [DSE,MSSA] Fix crash when using tryToMergePartialOverlappingStores.
We are re-using tryToMergePartialOverlappingStores, which requires
earlier to domiante Later. In the long run,
tryToMergeParialOverlappingStores should be re-written using MemorySSA.

Fixes PR46513.
2020-08-13 12:07:56 +01:00
Aditya Kumar f902a7eccf [HotColdSplit] Fix variable name spelling 2020-08-12 22:50:08 -07:00
Sanjay Patel 23bd33c6ac [InstCombine] prefer xor with -1 because 'not' is easier to understand (PR32706)
This is a retry of rL300977 which was reverted because of infinite loops.
We have fixed all of the known places where that would happen, but there's
still a chance that this patch will cause infinite loops.

This matches the demanded bits behavior in the DAG and should fix:
https://bugs.llvm.org/show_bug.cgi?id=32706

Differential Revision: https://reviews.llvm.org/D32255
2020-08-12 15:50:33 -04:00
Roman Lebedev d6f0600c96
[NFC][InstCombine] Add FIXME's for getLogBase2() / visitUDivOperand()
These are not correctness issues.

In visitUDivOperand(), if the (potential) divisor is undef, then udiv is
already UB, so it is not incorrect to keep undef as shift amount.

But, that is suboptimal.
We could instead simply drop that select, picking the other operand.

Afterwards, getLogBase2() could assert that there is no undef in divisor.
2020-08-12 22:06:54 +03:00
Roman Lebedev 12d93a27e7
[InstCombine] Sanitize undef vector constant to 1 in X*(2^C) with X << C (PR47133)
While x*undef is undef, shift-by-undef is poison,
which we must avoid introducing.

Also log2(iN undef) is *NOT* iN undef, because log2(iN undef) u< N.

See https://bugs.llvm.org/show_bug.cgi?id=47133
2020-08-12 22:06:53 +03:00
Ilya Leoshkevich f5a252ed68 [SanitizerCoverage] Use zeroext for cmp parameters on all targets
Commit 9385aaa848 ("[sancov] Fix PR33732") added zeroext to
__sanitizer_cov_trace(_const)?_cmp[1248] parameters for x86_64 only,
however, it is useful on other targets, in particular, on SystemZ: it
fixes swap-cmp.test.

Therefore, use it on all targets. This is safe: if target ABI does not
require zero extension for a particular parameter, zeroext is simply
ignored. A similar change has been implemeted as part of commit
3bc439bdff ("[MSan] Add instrumentation for SystemZ"), and there were
no problems with it.

Reviewed By: morehouse

Differential Revision: https://reviews.llvm.org/D85689
2020-08-12 18:38:12 +02:00
Sanjay Patel cc892fd9f4 [VectorCombine] early exit if target has no vector registers
Based on post-commit discussion in:
D81766

Other vectorization passes (SLP and Loop) use this TTI API similarly.
2020-08-12 09:22:31 -04:00
Sanjay Patel 912c09e845 [InstCombine] eliminate a pointer cast around insertelement
I'm not sure if this solves PR46839 completely, but reducing the casting should help:
https://bugs.llvm.org/show_bug.cgi?id=46839

Differential Revision: https://reviews.llvm.org/D85647
2020-08-12 09:08:17 -04:00
Sam Parker ea8448e361 [LoopUnroll] Adjust CostKind query
When TTI was updated to use an explicit cost, TCK_CodeSize was used
although the default implicit cost would have been the hand-wavey
cost of size and latency. So, revert back to this behaviour. This is
not expected to have (much) impact on targets since most (all?) of
them return the same value for SizeAndLatency and CodeSize.

When optimising for size, the logic has been changed to query
CodeSize costs instead of SizeAndLatency.

This patch also adds a testing option in the unroller so that
OptSize thresholds can be specified.

Differential Revision: https://reviews.llvm.org/D85723
2020-08-12 12:56:09 +01:00
Cullen Rhodes 511d5aaca3 [Transforms][SROA] Skip uses of allocas where the type is scalable
When visiting load and store instructions in SROA skip scalable vectors.
This is relevant in the implementation of the 'arm_sve_vector_bits'
attribute that is used to define VLS types, where an alloca of a
fixed-length vector could be bitcasted to scalable. See D85128 for more
information.

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D85725
2020-08-12 09:35:48 +00:00
Kyungwoo Lee d73be5af0a [NFC] Factor out hasForceAttributes
This is a preparation for https://reviews.llvm.org/D85586.

Differential Revision: https://reviews.llvm.org/D85793
2020-08-12 02:16:57 -04:00
Sanjay Patel b0b95dab1c [VectorCombine] add safety check for 0-width register
Based on post-commit discussion in D81766, Hexagon sets this to "0".
I'll see if I can come up with a test, but making the obvious
code fix first to unblock that target.
2020-08-11 20:30:02 -04:00