Commit Graph

346 Commits

Author SHA1 Message Date
Tobias Grosser 718d04c653 Use isl::manage_copy to simplify calls to isl::manage(isl_.._copy())
As part of this cleanup a couple of unnecessary isl::manage(obj.copy()) pattern
are eliminated as well.

We checked for all potential cleanups by scanning for:

  "grep -R isl::manage\( lib/ | grep copy"

llvm-svn: 325558
2018-02-20 07:26:58 +00:00
Tobias Grosser 5f62fafadd Do not call band_list().dump()
This is in preparation for the removal of band_list from isl.

llvm-svn: 325554
2018-02-20 07:24:40 +00:00
Michael Kruse 1ed2bc5266 [VirtualInst] Derive correct use kind of PHI operands. NFC.
VirtualUse::create is only called for MemoryKind::Value, but its
consistency nonetheless checked in verifyUses(). PHI uses are always
inter-stmt dependencies, which was not considered by the constructor
method. The virtual and non-virtual execution paths were the same, such
that verifyUses did not encounter any inconsistencies.

llvm-svn: 323283
2018-01-23 23:56:25 +00:00
Michael Kruse a0db63a195 [IslTools] dumpPw: Dump same structure pieces together.
Print same or similar structure elements together. Previously, the
value could take more importance that the space structure if visited
first in the space nest tree.

Before:
{
  Left[0] -> Right[i]: i >= 0;
  Left[1] -> AnotherRight[i];
  Left[2] -> Right[-1]
}

After:
{
  Left[0] -> Right[i]: i >= 0;
  Left[2] -> Right[-1];
  Left[1] -> AnotherRight[i]
}

llvm-svn: 322581
2018-01-16 18:39:42 +00:00
Philip Pfaffe 0969462c52 [NFC] Fix formatting
llvm-svn: 319973
2017-12-06 22:01:08 +00:00
Philip Pfaffe d98dbeeb71 Port SCEVAffinator to the isl c++ bindings
Summary: Straight forward port of SCEVAffinator

Reviewers: grosser, bollu, Meinersbur

Reviewed By: Meinersbur

Subscribers: pollydev, llvm-commits

Differential Revision: https://reviews.llvm.org/D40803

llvm-svn: 319958
2017-12-06 21:02:22 +00:00
Philip Pfaffe 4fe21814d1 Handle Top-Level-Regions in polly::isHoistableLoad
Summary:
This can be seen as a follow-up on my previous differential [D33411](https://reviews.llvm.org/D33411).
We received a bug report where this error was triggered. I have tried my best to recreate the issue in a minimal lit testcase which is also part of this differential.

I only handle return instructions as predecessors to a virtual TLR-exit right now. From inspecting the codebase, it seems `unreachable` instructions may also be of interest here. If requested, I can extend my patches to consider them as well. I would also apply this on `ScopHelper.cpp::isErrorBlock` (see D33411), of course.

Reviewers: philip.pfaffe, bollu

Reviewed By: bollu

Subscribers: Meinersbur, pollydev, llvm-commits

Tags: #polly

Differential Revision: https://reviews.llvm.org/D40492

llvm-svn: 319431
2017-11-30 13:06:10 +00:00
Michael Kruse 58166b13e0 Run polly-update-format. NFC.
polly-check-format has been failing since at least r318517,
due to more than one cause.

llvm-svn: 318795
2017-11-21 19:25:26 +00:00
Philip Pfaffe 00fd43b327 Port ScopInfo to the isl cpp bindings
Summary:
Most changes are mechanical, but in one place I changed the program semantics
by fixing a likely bug:

In `Scop::hasFeasibleRuntimeContext()`, I'm now explicitely handling the
error-case. Before, when the call to `addNonEmptyDomainConstraints()`
returned a null set, this (probably) accidentally worked because
isl_bool_error converts to true. I'm checking for nullptr now.

Reviewers: grosser, Meinersbur, bollu

Reviewed By: Meinersbur

Subscribers: nemanjai, kbarton, pollydev, llvm-commits

Differential Revision: https://reviews.llvm.org/D39971

llvm-svn: 318632
2017-11-19 22:13:34 +00:00
Michael Kruse b6b65834a1 [Simplify] Mark (and sweep) based on latest access relation.
Previously we marked scalars based on the original access function. However,
when a scalar read access is redirected, the original definition
(or incoming values of a PHI) is not used anymore, and can be deleted
(unless referenced by use that has not been redirected).

llvm-svn: 316660
2017-10-26 12:34:36 +00:00
Michael Kruse 25bd602b7a [ISLTools] Translate computeReachingWrite to isl++. NFC.
llvm-svn: 316445
2017-10-24 15:19:46 +00:00
Michael Kruse ed787e7540 [Polly] Add dumpPw() and dumpExpanded() functions. NFC.
These functions print a multi-line and sorted representation of unions
of polyhedra. Each polyhedron (basic_{ast/map}) has its own line.
First sort key is the polyhedron's hierachical space structure.
Secondary sort key is the lower bound of the polyhedron, which should
ensure that the polyhedral are printed in approximately ascending order.

Example output of dumpPw():
[p_0, p_1, p_2] -> {
  Stmt0[0] -> [0, 0];
  Stmt0[i0] -> [i0, 0] : 0 < i0 <= 5 - p_2;
  Stmt1[0] -> [0, 2] : p_1 = 1 and p_0 = -1;
  Stmt2[0] -> [0, 1] : p_1 >= 3 + p_0;
  Stmt3[0] -> [0, 3];
}

In contrast dumpExpanded() prints each point in the sets, unless there
is an unbounded dimension that cannot be expandend.
This is useful for reduced test cases where the loop counts are set to
some constant to understand a bug.

Example output of dumpExpanded(
{ [MemRef_A[i0] -> [i1]] : (exists (e0 = floor((1 + i1)/3): i0 = 1 and
3e0 <= i1 and 3e0 >= -1 + i1 and i1 >= 15 and i1 <= 25)) or (exists (e0
= floor((i1)/3): i0 = 0 and 3e0 < i1 and 3e0 >= -2 + i1 and i1 > 0 and
i1 <= 11)) }):

{
  [MemRef_A[0] ->[1]];
  [MemRef_A[0] ->[2]];
  [MemRef_A[0] ->[4]];
  [MemRef_A[0] ->[5]];
  [MemRef_A[0] ->[7]];
  [MemRef_A[0] ->[8]];
  [MemRef_A[0] ->[10]];
  [MemRef_A[0] ->[11]];
  [MemRef_A[1] ->[15]];
  [MemRef_A[1] ->[16]];
  [MemRef_A[1] ->[18]];
  [MemRef_A[1] ->[19]];
  [MemRef_A[1] ->[21]];
  [MemRef_A[1] ->[22]];
  [MemRef_A[1] ->[24]];
  [MemRef_A[1] ->[25]]
}

Differential Revision: https://reviews.llvm.org/D38349

llvm-svn: 314525
2017-09-29 15:45:40 +00:00
Michael Kruse 89d2be0702 [Support] Force instantiation of isl dump() methods. NFC.
In order for debuggers to be able to call an inline method, it must have
been instantiated somewhere. The dump() methods are usually not used, so
add an instantiation in debug builds.

This allows to call .dump() on any isl++ object from the gcc/gdb and
Visual Studio debugger in debug builds with assertions enabled.
In optimized builds, even with assertions enabled, the dump() methods
are also inlined in GICHelper.cpp, so no externally visible symbols
will be available either.

Differential Revision: https://reviews.llvm.org/D38198

llvm-svn: 314395
2017-09-28 09:51:04 +00:00
Tobias Grosser 0a62b2d887 [ScopInfo] Allow uniform branch conditions
If all but one branch come from an error condition and the incoming value from
this branch is a constant, we can model this branch.

llvm-svn: 314116
2017-09-25 16:37:15 +00:00
Tobias Grosser ee457594c2 [ScopDetect/Info] Look through PHIs that follow an error block
In case a PHI node follows an error block we can assume that the incoming value
can only come from the node that is not an error block. As a result, conditions
that seemed non-affine before are now in fact affine.

This is a recommit of r312663 after fixing
test/Isl/CodeGen/phi_after_error_block_outside_of_scop.ll

llvm-svn: 314075
2017-09-24 09:25:30 +00:00
Reid Kleckner 3fc649cb76 [Support] Rename tool_output_file to ToolOutputFile, NFC
This class isn't similar to anything from the STL, so it shouldn't use
the STL naming conventions.

llvm-svn: 314050
2017-09-23 01:03:17 +00:00
Michael Kruse 8ee179d3b4 Revert "[ScopDetect/Info] Look through PHIs that follow an error block"
This reverts commit
r312410 - [ScopDetect/Info] Look through PHIs that follow an error block

The commit caused generation of invalid IR due to accessing a parameter
that does not dominate the SCoP.

llvm-svn: 312663
2017-09-06 19:05:40 +00:00
Tobias Grosser 8703e38380 [ISLTools]: Move singleton to isl++
llvm-svn: 312476
2017-09-04 10:05:29 +00:00
Tobias Grosser 99ccf05694 [ScopHelper] Do not crash on unreachable blocks
This resolves llvm.org/PR34433. Thanks to Zhendong Su for reporting.

llvm-svn: 312451
2017-09-03 18:01:22 +00:00
Tobias Grosser 4baedc70d1 [ScopDetect/Info] Look through PHIs that follow an error block
In case a PHI node follows an error block we can assume that the incoming value
can only come from the node that is not an error block. As a result, conditions
that seemed non-affine before are now in fact affine.

llvm-svn: 312410
2017-09-02 08:25:55 +00:00
Michael Kruse 0c6c555beb Fix Memory Access of failing tests.
Mark scalar dependences for different statements belonging to same BB
as 'Inter'.

Contributed-by: Nandini Singhal <cs15mtech01004@iith.ac.in>

Differential Revision: https://reviews.llvm.org/D37147

llvm-svn: 312324
2017-09-01 11:36:52 +00:00
Tobias Grosser 2307f86c47 [ForwardOpTree] Allow forwarding in the presence of region statements
Summary:
After region statements now also have instruction lists, this is a
straightforward extension.

Reviewers: Meinersbur, bollu, singam-sanjay, gareevroman

Reviewed By: Meinersbur

Subscribers: hfinkel, pollydev, llvm-commits

Tags: #polly

Differential Revision: https://reviews.llvm.org/D37298

llvm-svn: 312249
2017-08-31 16:04:49 +00:00
Michael Kruse 99cc9ded41 Do not consider mem intrinsics as error.
The intrinsics memset, memcopy and memmove do have their memory accesses
modeled by ScopBuilder. Do not consider them error-case behavior.

Test case will come with a future patch that requires memory intrinsics
outside of error blocks.

llvm-svn: 312021
2017-08-29 18:27:47 +00:00
Michael Kruse 25d3f85a43 Skip ignored intrinsics.
Commit r252725 introduced a "return false" if an ignored intrinsics was
found. The consequence of this was that the mere existence of an ignored
intrinsic (such as llvm.dbg.value) before a call that would have
qualified the block to be an error block, to not be an error block.

The obvious goal was to just skip ignored intrinsics, not changing the
meaning of what an error block is.

llvm-svn: 312020
2017-08-29 18:27:42 +00:00
Michael Kruse 4728184342 [ZoneAlgo] More fine-grained bail-out.
ZoneAlgo used to bail out for the complete SCoP if it encountered
something violating its assumption. This meant the neither OpTree can
forward any load nor DeLICM do anything in such cases, even if their
transformations are unrelated to the violations.

This patch adds a list of compatible elements (currently with the
granularity of entire arrays) that can be used for analysis. OpTree
and DeLICM can then check whether their transformations only concern
compatible elements, and skip non-compatible ones.

This will be useful for e.g. Polybench's benchmarks covariance,
correlation, bicg, doitgen, durbin, gramschmidt, adi that have
assumption violation, but which are not necessarily relevant
for all transformations.

Differential Revision: https://reviews.llvm.org/D37219

llvm-svn: 311929
2017-08-28 20:39:07 +00:00
Michael Kruse 06ed529205 Add more statistics.
Add statistics about
- Which optimizations are applied
- Number of loops in Scops at various stages
- Number of scalar/singleton writes at various stages representative
  for scalar false dependencies
- Number of parallel loops

These will be useful to find regressions due to moving Polly further
down of LLVM's pass pipeline.

Differential Revision: https://reviews.llvm.org/D37049

llvm-svn: 311553
2017-08-23 13:50:30 +00:00
Michael Kruse ade14269cd [DeLICM] Fix unused zone for writes without in-between read.
The implementation of computeArrayUnused did not consider writes without
reads before, except for the first write in the SCoP. This caused it to
'forget' writes directly following another write.

This patch re-adds the entire reaching defintion of a write that has not
been covered before by a read.

This fixes Polybench 4.2 2mm where only one of the matrix-multiplication
was detected.

llvm-svn: 311403
2017-08-21 23:04:45 +00:00
Siddharth Bhat b46847c035 [ScopInliner] Add a simple Scop-based inliner to polly.
We add a ScopInliner pass which inlines functions based on a simple heuristic:
Let `g` call `f`.
If we can model all of `f` as a Scop, we inline `f` into `g`.

This requires `-polly-detect-full-function` to be enabled. So, the pass
asserts that `-polly-detect-full-function` is enabled.

Differential Revision: https://reviews.llvm.org/D36832

llvm-svn: 311126
2017-08-17 21:57:23 +00:00
Tobias Grosser ed6a4acc7f Add rewrite by-reference parameter pass
Summary:
This pass detangles induction variables from functions, which take variables by
reference. Most fortran functions compiled with gfortran pass variables by
reference. Unfortunately a common pattern, printf calls of induction variables,
prevent in this situation the promotion of the induction variable to a register,
which again inhibits any kind of loop analysis. To work around this issue
we developed a specialized pass which introduces separate alloca slots for
known-read-only references, which indicate the mem2reg pass that the induction
variables can be promoted to registers and consquently enable SCEV to work.

We currently hardcode the information that a function
_gfortran_transfer_integer_write does not read its second parameter, as
dragonegg does not add the right annotations and we cannot change old dragonegg
releases. Hopefully flang will produce the right annotations.

Reviewers: Meinersbur, bollu, singam-sanjay

Reviewed By: bollu

Subscribers: mgorny, pollydev, llvm-commits

Tags: #polly

Differential Revision: https://reviews.llvm.org/D36800

llvm-svn: 311066
2017-08-17 05:25:08 +00:00
Philip Pfaffe 47bf15c34f [JSON][PM] Port json import/export over to new pm
Summary:
I pulled out all functionality into static functions, and use those both
in the legacy passes and in the new ones.

Reviewers: grosser, Meinersbur, bollu

Reviewed By: Meinersbur

Subscribers: llvm-commits, pollydev

Differential Revision: https://reviews.llvm.org/D36578

llvm-svn: 310597
2017-08-10 14:45:09 +00:00
Siddharth Bhat c4a4af47f3 [ManagedMemoryRewrite] Introduce a new pass to rewrite modules to use managed memory.
This pass is useful to automatically convert a codebase that uses malloc/free
to use their managed memory counterparts.

Currently, rewrite malloc and free to the `polly_{malloc,free}Managed` variants.

A future patch will teach ManagedMemoryRewrite to rewrite global arrays
as pointers to globally allocated managed memory.

Differential Revision: https://reviews.llvm.org/D36513

llvm-svn: 310471
2017-08-09 12:59:23 +00:00
Michael Kruse 630fc7b82a [ISLTools/ZoneAlgo] Make distributeDomain and filterKnownValInst isl_error_quota proof.
distributeDomain() and filterKnownValInst() are used in a scop
of ForwardOpTree that limits the number of isl operations.
Therefore some isl functions may return null after any operation.

Remove assertion that assume non-null results and handle
isl_*_foreach returning isl::stat::error.

I hope this fixes the crash of the asop buildbot at ihevc_recon.c.

llvm-svn: 310461
2017-08-09 11:21:40 +00:00
Tobias Grosser 79d9c29310 [RegisterPasses] Run polly-simplify also right after scop modeling
This allows us to get rid of stores that are overwritten within the very same
basic block, without ever being read beforehand. This simplification is
necessary for delicm to run on pb4's correlation.

llvm-svn: 310369
2017-08-08 15:14:46 +00:00
Tobias Grosser 50206d8f57 Change Polly's position to "before-vectorizer"
Polly has traditionally always been executed at the beginning of the pass
pipeline as LLVM's inliner and DeLICM passes introduced plenty of scalar
dependences which prevented any kind of useful high-level loop optimizations
later in the pass pipeline. With DeLICM now being available, Polly can also
run optimizations when folded into the pass pipeline. This has the benefit
that Polly should now be more effective on C++ code and as an additional bonus,
no additional early canonicalization phase must be run. As a result, Polly
touches the code only if it applies a transformation. Code that does not
benefit from Polly is not touched and consequently will have the very same
execution time as without Polly enabled. Random performance changes, as could
sometimes be observed with polly-position=early are consequently not possible
any more. If performance is changed, this is due to Polly is choosing to
perform a transformation. If this choice is wrong, it can be fixed directly
in Polly.

http://polly.llvm.org/docs/Architecture.html#polly-in-the-llvm-pass-pipeline

llvm-svn: 310319
2017-08-07 22:33:34 +00:00
Tobias Grosser ad73f6a7b3 Enable delicm to automatically remove scalar loop carried dependences
While this code is still rather we enable it by default to get better test
coverage.

llvm-svn: 310313
2017-08-07 22:04:20 +00:00
Andreas Simbuerger 81fb6b3e40 [Polly] Fully-Indexed static expansion
This commit implements the initial version of fully-indexed static
expansion.

```
 for(int i = 0; i<Ni; i++)
   for(int j = 0; j<Ni; j++)
S:     B[j] = j;
T: A[i] = B[i]
```

After the pass, we want this :
```
 for(int i = 0; i<Ni; i++)
   for(int j = 0; j<Ni; j++)
S:     B[i][j] = j;
T: A[i] = B[i][i]
```

For now we bail (fail) in the following cases:
  - Scalar access
  - Multiple writes per SAI
  - MayWrite Access
  - Expansion that leads to an access to the original array

Furthermore: We still miss checks for escaping references to the array
base pointers. A future commit will add the missing escape-checks to
stay correct in those cases. The expansion is still locked behind a
CLI-Option and should not yet be used.

Patch contributed by: Nicholas Bonfante <bonfante.nicolas@gmail.com>

Reviewers: simbuerg, Meinersbur, bollu

Reviewed By: Meinersbur

Subscribers: mgorny, llvm-commits, pollydev

Differential Revision: https://reviews.llvm.org/D34982

llvm-svn: 310304
2017-08-07 20:54:20 +00:00
Michael Kruse 70af4f579d [ForwardOpTree] Use known array content analysis to forward load instructions.
This is an addition to the -polly-optree pass that reuses the array
content analysis from DeLICM to find array elements that contain the
same value as the value loaded when the target statement instance
is executed.

The analysis is now enabled by default.

The known content analysis could also be used to rematerialize any
llvm::Value that was written to some array element, but currently
only loads are forwarded.

Differential Revision: https://reviews.llvm.org/D36380

llvm-svn: 310279
2017-08-07 18:40:29 +00:00
Tobias Grosser 61bd3a4840 [ScopInfo] Move Scop::getPwAffOnly to isl++ [NFC]
llvm-svn: 310231
2017-08-06 21:42:38 +00:00
Tobias Grosser 9a63570b13 [ScopInfo] Translate Scop::getIdForParam to isl++ [NFC]
llvm-svn: 310220
2017-08-06 19:31:27 +00:00
Michael Kruse 1046aa3148 [VirtualInstruction] Handle MetadataAsValue as constant.
The complication of bspatch.cc of the AOSP buildbot currently fails
presumably because the occurance of a MetadataAsValue in an operand.
This kind of value can occur as operands of intrinsics, the typical
example being the debug intrinsics.

Polly currently ignores the debug intrinsics and it is not yet clear
which other intrinic might occur. For such cases, and to unbreak the
AOSP buildbot, treat a MetadataAsValue as a constant because it can be
referenced without modification in generated code.

llvm-svn: 309992
2017-08-03 22:00:01 +00:00
Michael Kruse 672c011460 [VirtualInstruction] Avoid use of getStmtFor(BB). NFC.
With this patch, we get rid of the last use of getStmtFor(BB). Here
this is done by getting the last statement of the incoming block in
case the user is a phi node; otherwise just fetching the statement
comprising the instruction for which the virtual use is being created.

Differential Revision: https://reviews.llvm.org/D36268

llvm-svn: 309947
2017-08-03 15:27:00 +00:00
Tobias Grosser a195576118 Enable simplify and forward-op-tree by default
These passes have been tested over the last month and should generally help
to remove scalar data dependences in Polly. We enable them to give them even
wider test coverage. Large performance regressions and any kind of correctness
regressions are not expected.

llvm-svn: 309878
2017-08-02 20:12:27 +00:00
Tobias Grosser 18ca9e5119 Replace asserts with llvm_unreachable to clarify intent
llvm-svn: 309856
2017-08-02 19:11:46 +00:00
Philip Pfaffe a70e2649ab [Polly][PM][WIP] Polly pass registration
Summary:
This patch is a first attempt at registering Polly passes with the LLVM tools. Tool plugins are still unsupported, but this registration is usable from the tools if Polly is linked into them (albeit requiring minimal patches to those tools). Registration requires a small amount of machinery (the owning analysis proxies), necessary for injecting ScopAnalysisManager objects into the calling tools.

This patch is marked WIP because the registration is incomplete. Parsing manual pipelines is fully supported, but default pass injection into the O3 pipeline is lacking, mostly because there is opportunity for some redesign here, I believe. The first point of order would be insertion points. I think it makes sense to run before the vectorizers. Running Polly Early, however, is weird. Mostly because it actually is the default (which to me is unexpected), and because Polly runs it's own O1 pipeline. Why not instead insert it at an appropriate place somewhere after simplification happend? Running after the loop optimizers seems intuitive, but it also seems wasteful, since multiple consecutive loops might well be a single scop, and we don't need to run for all of them.

My second request for comments would be regarding all those smallish helper passes we have,  like PollyViewer, PollyPrinter, PollyImportJScop. Right now these are controlled by command line options, deciding whether they should be part of the Polly pipeline. What is your opinion on treating them like real passes, and have the user write an appropriate pipeline if they want to use any of them?

Reviewers: grosser, Meinersbur, bollu

Reviewed By: grosser

Subscribers: llvm-commits, pollydev

Tags: #polly

Differential Revision: https://reviews.llvm.org/D35458

llvm-svn: 309826
2017-08-02 15:52:25 +00:00
Michael Kruse 8e41d2baab [Simplify] Do not remove dependencies of phis within region stmts.
These were wrongly assumed to be phi nodes that require
MemoryKind::PHI accesses.

llvm-svn: 309454
2017-07-28 23:22:32 +00:00
Michael Kruse fd7f40961b [VirtualInstruction] Do not iterate over a region statement's instruction list. NFC.
It should be empty anyways. In this case it would even be redundant
because we just all all instructions in region statements.

llvm-svn: 309453
2017-07-28 23:22:23 +00:00
Michael Kruse a508a4e619 [ScopBuilder/Simplify] Refactor isEscaping. NFC.
ScopBuilder and Simplify (through VirtualInstruction.cpp) previously
used this functionality in their own implementation. Refactor them
both into a common one into the Scop class.

BlockGenerator also makes use of a similiar functionality, but also
records outside users and takes place after region simplification.
Merging it as well would be more complicated.

llvm-svn: 309273
2017-07-27 14:39:52 +00:00
Michael Kruse 8a8aca4299 [Simplify] Count PHINodes in simplifiable exit nodes as escaping use.
After region exit simplification, the incoming block of a phi node in
the SCoP region's exit block lands outside of the region. Since we
treat SCoPs as if this already happened, we need to account for that
when looking for outside uses of scalars (i.e. escaping scalars).

llvm-svn: 309271
2017-07-27 14:09:31 +00:00
Michael Kruse 95b39da8ae [Simplify] Fix invalid removal write for escaping values.
A PHI node's incoming block is the user of its operand, not the PHI's parent.

Assuming the PHINode's parent being the user lead to the removal of a
MemoryAccesses because its use was assumed to be inside of the SCoP.

llvm-svn: 309164
2017-07-26 19:58:15 +00:00
Michael Kruse 11ed062258 [SCEVValidator] Loop exit values of loops before the SCoP are synthesizable.
In the following loop:

   int i;
   for (i = 0; i < func(); i+=1)
     ;
SCoP:
   for (int j = 0; j<n; j+=1)
     S(i, j)

The value i is synthesizable in the SCoP that includes only the j-loop.
This is because i is fixed within the SCoP, it is irrelevant whether
it originates from another loop.

This fixes a strange case where a PHI was synthesiable in a SCoP,
but not its incoming value, triggering an assertion.

This should fix MultiSource/Applications/sgefa/sgefa of the
perf-x86_64-penryn-O3-polly-before-vectorizer-unprofitable buildbot.

llvm-svn: 309109
2017-07-26 13:05:45 +00:00