471 Commits

Author SHA1 Message Date
Arthur Eubanks
d623b2f95f [PassManagerBuilder] Remove PassManagerBuilder
PassManagerBuilder is dead, long live PassBuilder!

bugpoint's -O# are now useless (and probably have been for a while given the number of passes we've removed from PassManagerBuilder). Perhaps they'll be revived if bugpoint ever works with the new PM.

Reviewed By: nikic, MaskRay

Differential Revision: https://reviews.llvm.org/D145835
2023-03-13 09:30:30 -07:00
Michael Kruse
19afbfe331 [Polly] Remove Polly-ACC.
Polly-ACC is unmaintained and since it has never been ported to the NPM pipeline, since D136621 it is not even accessible anymore without manually specifying the passes on the `opt` command line.

Since there is no plan to put it to a maintainable state, remove it from Polly.

Reviewed By: grosser

Differential Revision: https://reviews.llvm.org/D142580
2023-03-08 17:33:04 -06:00
Michael Kruse
42cd38c01e [Polly] Remove -polly-vectorizer=polly.
Polly's internal vectorizer is not well maintained and is known to not work in some cases such as region ScopStmts. Unlike LLVM's LoopVectorize pass it also does not have a target-dependent cost heuristics, and we recommend using LoopVectorize instead of -polly-vectorizer=polly.

In the future we hope that Polly can collaborate better with LoopVectorize, like Polly marking a loop is safe to vectorize with a specific simd width, instead of replicating its functionality.

Reviewed By: grosser

Differential Revision: https://reviews.llvm.org/D142640
2023-03-08 12:51:42 -06:00
Paul Walker
62d11b2cca Revert "Revert "[SCEV] Add SCEVType to represent vscale.""
Relanding after fixing Polly related build error.

This reverts commit 7b26dcae9eaf8cdcba7fef032fd83d060dffd4b4.
2023-03-02 13:14:07 +00:00
Florian Hahn
934c82d318
[Polly] Remove CodegenCleanupPass.
The pass uses a bunch of deprecated legacy passes and appears unused.
Remove it to unblock removing legacy passes.

Fixes https://github.com/llvm/llvm-project/issues/60852

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D144332
2023-02-24 13:39:32 +01:00
Kazu Hirata
a28b252d85 Use APInt::getSignificantBits instead of APInt::getMinSignedBits (NFC)
Note that getMinSignedBits has been soft-deprecated in favor of
getSignificantBits.
2023-02-19 23:56:52 -08:00
Kazu Hirata
ccdc271a08 [polly] Use std::optional instead of llvm::Optional (NFC)
This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2023-01-02 19:18:46 -08:00
Kazu Hirata
043aa1dbba [polly] Use std::nullopt instead of None (NFC)
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated.  The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2022-12-03 18:50:29 -08:00
Arthur Eubanks
c7ca01b8d7 [polly] Format RegisterPasses.cpp 2022-10-28 10:25:46 -07:00
Arthur Eubanks
f7985dda22 [polly] Remove legacy pass manager hooks
And some options that only throw errors with the new PM.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D136621
2022-10-28 10:16:34 -07:00
Michael Kruse
b150d34c47 [Polly] Add support for -polly-enable-mse with NPM.
The MaximalStaticExpansionPass was already ported to the NPM in
02f640672e2875c4e7578366bb2e22582548d7c1. Allow adding it to the default
NPM pass builder pipeline using -polly-enable-mse.
2022-10-26 17:27:31 -05:00
Michael Kruse
bb90d7ee39 [Polly] Add support for -polly-export with NPM.
The JSONExporter pass was already ported to the NPM, the pass builder
jsut had to add it to the pass pipeline when requested.
2022-10-26 17:21:34 -05:00
Fangrui Song
0972a390b9 LLVM_FALLTHROUGH => [[fallthrough]]. NFC 2022-08-09 04:06:52 +00:00
Roman Gareev
b02c7e2b63 [Polly] Generalize the pattern matching to the case of tensor contractions
The pattern matching optimization of Polly detects and optimizes dense general
matrix-matrix multiplication. The generated code is close to high performance
implementations of matrix-matrix multiplications, which are contained in
manually tuned libraries. The described pattern matching optimization is
a particular case of tensor contraction optimization, which was
introduced in [1].

This patch generalizes the pattern matching to the case of tensor contractions
using the form of data dependencies and memory accesses produced by tensor
contractions [1].

Optimization of tensor contractions will be added in the next patch. Following
the ideas introduced in [2], it will logically represent tensor contraction
operands as matrix multiplication operands and use an approach for
optimization of matrix-matrix multiplications.

[1] - Gareev R., Grosser T., Kruse M. High-Performance Generalized Tensor
Op­erations: A Compiler-Oriented Approach // ACM Transactions on
Architec­ture and Code Optimization (TACO). 2018. Vol. 15, no. 3.
P. 34:1–34:27. DOI: 10.1145/3235029.

[2] - Matthews D. High-Performance Tensor Contraction without BLAS // SIAM
Journal on Scientific Computing. 2018. Vol. 40, no. 1. P. C 1—C 24.
DOI: 110.1137/16m108968x.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D114336
2022-08-07 13:10:32 +03:00
Kazu Hirata
3f3930a451 Remove redundaunt virtual specifiers (NFC)
Identified with tidy-modernize-use-override.
2022-07-25 23:00:59 -07:00
Kazu Hirata
30c675878c Use value_or instead of getValueOr (NFC) 2022-06-19 10:34:41 -07:00
Fangrui Song
95a134254a Remove unneeded cl::ZeroOrMore for cl::opt/cl::list options 2022-06-05 01:07:51 -07:00
Fangrui Song
d86a206f06 Remove unneeded cl::ZeroOrMore for cl::opt/cl::list options 2022-06-05 00:31:44 -07:00
Fangrui Song
36c7d79dc4 Remove unneeded cl::ZeroOrMore for cl::opt options
Similar to 557efc9a8b68628c2c944678c6471dac30ed9e8e.
This commit handles options where cl::ZeroOrMore is more than one line below
cl::opt.
2022-06-04 00:10:42 -07:00
Yang Keao
02f640672e [Polly] Migrate -polly-mse to the new pass manager.
This patch implements the `MaximalStaticExpansion` and its printer in NPM.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D125870
2022-06-01 13:37:58 -05:00
Michael Kruse
bd93df937a [Polly] Mark classes as final by default. NFC.
This make is obivious that a class was not intended to be derived from.

NPM analysis pass can unfortunately not marked as final because they are
derived from a llvm::Checker<T> template internally by the NPM.

Also normalize the use of classes/structs
 * NPM passes are structs
 * Legacy passes are classes
 * structs that have methods and are not a visitor pattern are classes
 * structs have public inheritance by default, remove "public" keyword
 * Use typedef'ed type instead of inline forward declaration
2022-05-17 12:05:39 -05:00
Michael Kruse
6b3b87376b [polly] migrate -polly-show to the new pass manager
Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D123678
2022-05-09 14:04:29 -05:00
Michael Kruse
5c02808131 [polly] Introduce -polly-print-* passes to replace -analyze.
The `opt -analyze` option only works with the legacy pass manager and might be removed in the future, as explained in llvm.org/PR53733. This patch introduced -polly-print-* passes that print what the pass would print with the `-analyze` option and replaces all uses of `-analyze` in the regression tests.

There are two exceptions: `CodeGen\single_loop_param_less_equal.ll` and `CodeGen\loop_with_condition_nested.ll` use `-analyze on the `-loops` pass which is not part of Polly.

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D120782
2022-03-14 10:27:15 -05:00
Michael Kruse
ad84c6f657 [polly] Match function definitions and header declarations. NFC.
Ensure that function definitions match their declrations in header
files, even if they have no effect on linking. This includes

 1. Both have the same __isl_* annotations

 2. Both use the same type alias

 3. Remove unused declarations that have no definition

 4. Use explicit polly namespace qualifier for definitions; generally,
    the .cpp file should use at most an anon namespace region since
    only symbols declared in the header file can be accessed from other
    translation units anyway. For defintions that have been declared in
    the header file, the explicit namespace qualifier ensures that both
    match.
2022-02-16 12:52:17 -06:00
Christopher Di Bella
e51e7e7f44 [polly][NFC] removes using-directives to fix modules build
When compiling with Clang modules enabled, polly's use of using-directives
caused the global object `Target` in RegisterPasses.cpp to clash with
`llvm::Target`. By eliminating the using-directives, we're able to get
polly to play nicely with a modules build.

Differential Revision: https://reviews.llvm.org/D119809
2022-02-15 18:58:22 +00:00
Roman Lebedev
82fb4f4b22
[SCEV] Sequential/in-order UMin expression
As discussed in https://github.com/llvm/llvm-project/issues/53020 / https://reviews.llvm.org/D116692,
SCEV is forbidden from reasoning about 'backedge taken count'
if the branch condition is a poison-safe logical operation,
which is conservatively correct, but is severely limiting.

Instead, we should have a way to express those
poison blocking properties in SCEV expressions.

The proposed semantics is:
```
Sequential/in-order min/max SCEV expressions are non-commutative variants
of commutative min/max SCEV expressions. If none of their operands
are poison, then they are functionally equivalent, otherwise,
if the operand that represents the saturation point* of given expression,
comes before the first poison operand, then the whole expression is not poison,
but is said saturation point.
```
* saturation point - the maximal/minimal possible integer value for the given type

The lowering is straight-forward:
```
compare each operand to the saturation point,
perform sequential in-order logical-or (poison-safe!) ordered reduction
over those checks, and if reduction returned true then return
saturation point else return the naive min/max reduction over the operands
```
https://alive2.llvm.org/ce/z/Q7jxvH (2 ops)
https://alive2.llvm.org/ce/z/QCRrhk (3 ops)
Note that we don't need to check the last operand: https://alive2.llvm.org/ce/z/abvHQS
Note that this is not commutative: https://alive2.llvm.org/ce/z/FK9e97

That allows us to handle the patterns in question.

Reviewed By: nikic, reames

Differential Revision: https://reviews.llvm.org/D116766
2022-01-10 20:51:26 +03:00
Kazu Hirata
76f0f1cc5c Use {DenseSet,SetVector,SmallPtrSet}::contains (NFC) 2021-12-24 21:43:06 -08:00
Fangrui Song
0b39ec835d [Polly][Isl] Fix -Wsign-compare after D113101 2021-11-11 00:17:52 -08:00
Riccardo Mori
44596fe6a9 [Polly][Isl] Use the function unsignedFromIslSize to manage a isl::size object. NFCI
This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in lib/External/isl/include/isl/isl-noxceptions.h and the official isl C++ interface.
In the official interface the type `isl::size` cannot be casted to an unsigned without previously having checked if it contains a valid value with the function `isl::size::is_error()`.
For this reason two helping functions have been added:
 - `IslAssert`: assert that no errors are present in debug builds and just disables the mandatory error check in non-debug builds
 - `unisgnedFromIslSIze`: cast the `isl::size` object to `unsigned`

Changes made:
 - Add the functions `IslAssert` and `unsignedFromIslSize`
 - Add the utility function `rangeIslSize()`
 - Retype `MaxDisjunctsInDomain` from `int` to `unsigned`
 - Retype `RunTimeChecksMaxAccessDisjuncts` from `int` to `unsigned`
 - Retype `MaxDimensionsInAccessRange` from `int` to `unsigned`
 - Replaced some usages of `isl_size` to `unsigned` since we aim not to use `isl_size` anymore
 - `isl-noexceptions.h` has been generated by e704f73c88

No functional change intended.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D113101
2021-11-05 11:15:22 +01:00
Michael Kruse
19db33c06e [Polly] Remove support for code generated by gfortran+DragonEgg.
DragonEgg is not maintained anymore, hence there is no need for this
functionality.

Fixes llvm.org/PR52173
2021-10-14 14:12:06 -05:00
Michael Kruse
ec2029f986 [Polly] Do not inline dumpIslObj methods. NFC.
Instead of being inline and having a neverCalled() workaround to make it
work in the debugger, define it as a regular exported function.

Also add overloads for the C API types isl_* so it works with managed as
well as unmanaged ISL objects.
2021-10-12 23:52:36 -05:00
Michael Kruse
64489255be [Polly] Add greedy fusion algorithm.
When the option -polly-loopfusion-greedy is set, the ScheduleOptimizer
tries to aggressively fuse any band it can and does not violate any
dependences.

As part if the implementation, the functionalty for copying a band
into an new schedule was extracted out of the ScheduleTreeRewriter.
2021-10-08 20:33:30 -05:00
Michael Kruse
9820dd970c [Polly] Support for InlineAsm.
Inline assembly was not handled at all and treated like a llvm::Value.
In particular, it tried to create a pointer it which is not allowed.

Fix by handling like a llvm::Constant such that it is just reused when
required, instead of trying to marshall it in memory.

Fixes llvm.org/PR51960
2021-09-26 03:26:43 -05:00
Michael Kruse
1cea25eec9 [Polly] Remove isConstCall.
The function was intended to catch OpenMP functions such as
get_thread_id(). If matched, the call would be considered synthesizable.

There were a few problems with this:

 * get_thread_id() is not 'const' in the sense of have the gcc manual
   defines it: "do not examine any values except their arguments".
   get_thread_id() reads OpenCL runtime libreary global state.
   What was inteded was probably 'speculable'.

 * isConstCall was implemented using mayReadOrWriteMemory(). 'const' is
   stricter than that, mayReadOrWriteMemory is e.g. true for malloc(),
   since it may only read/write addresses that are considered
   inaccessible fro the application. However, malloc is certainly not
   speculable.

 * Values that are isConstCall were not handled consistently throughout
   Polly. In particular, it was not considered for referenced values
   (OpenMP outlining and PollyACC).

Fix by removing special handling for isConstCall entirely.
2021-09-26 03:26:43 -05:00
Michael Kruse
e4f3f2c0c5 [Polly] Don't prune non-external function itself from dump. 2021-08-28 17:06:53 -05:00
Michael Kruse
9cfab5e249 [Polly] Add support for -polly-dump-before/after with NPM.
The new pass manager does not allow adding module passes at the
-polly-position=before-vectorizer extension point. Introduce a
DumpFunctionPass that dumps only current function. In contrast to the
legacy pass manager's -polly-dump-before, each function will be dumped
into its own file. -polly-dump-before-file is still not supported.

The DumpFunctionPass uses llvm::CloneModule to copy the current function
into a new module and then write it into a file.
2021-08-22 20:43:35 -05:00
Michael Kruse
58e4e71fc8 [Polly] Introduce caching for the isErrorBlock function. NFC.
Compilation of the file insn-attrtab.c of the SPEC CPU 2017 502.gcc_r
benchmark takes excessive time (> 30min) with Polly enabled. Most time
is spent in the isErrorBlock function querying the DominatorTree.
The isErrorBlock is invoked redundantly over the course of ScopDetection
and ScopBuilder. This patch introduces a caching mechanism for its
result.

Instead of a free function, isErrorBlock is moved to ScopDetection where
its cache map resides. This also means that many functions directly or
indirectly calling isErrorBlock are not "const" anymore. The
DetectionContextMap was marked as "mutable", but IMHO it never should
have been since it stores the detection result.

502.gcc_r only takes excessive time with the new pass manager. The
reason seeams to be that it invalidates the ScopDetection analysis more
often than the legacy pass manager, for unknown reasons.
2021-08-18 14:05:50 -05:00
Michael Kruse
e8c8407aca [Polly] Break early when the result is known. NFC. 2021-08-18 12:41:04 -05:00
Riccardo Mori
d3fdbda6b0 [Polly][Isl] Move to the new-polly-generator branch version of isl-noexceptions.h. NFCI
This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

With this commit we are moving from the `polly-generator` branch to the `new-polly-generator` branch that is more mantainable and is based on the official C++ interface `cpp-checked.h`.

Changes made:
 - There are now many sublcasses for `isl::ast_node` representing different isl types. Use `isl::ast_node_for`, `isl::ast_node_user`, `isl::ast_node_block` and `isl::ast_node_mark` where needed.
 - There are now many sublcasses for `isl::schedule_node` representing different isl types. Use `isl::schedule_node_mark`, `isl::schedule_node_extension`, `isl::schedule_node_band` and `isl::schedule_node_filter` where needed.
 - Replace the `isl::*::dump` with `dumpIslObj` since the isl dump method is not exposed in the C++ interface.
 - `isl::schedule_node::get_child` has been renamed to `isl::schedule_node::child`
 - `isl::pw_multi_aff::get_pw_aff` has been renamed to `isl::pw_multi_aff::at`
 - The constructor `isl::union_map(isl::union_pw_multi_aff)` has been replaced with the static method `isl::union_map::from()`
 - Replace usages of `isl::val::add_ui` with `isl::val::add`
 - `isl::union_set_list::alloc` is now a constructor
 - All the `isl_size` values are now wrapped inside the class `isl::size` use `isl::size::release` to get the internal `isl_size` value where needed.
 - `isl-noexceptions.h` has been generated by 73f5ed1f4d

No functional change intended.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D107225
2021-08-16 15:53:26 +02:00
Tarindu Jayatilaka
7a797b2902 Take OptimizationLevel class out of Pass Builder
Pulled out the OptimizationLevel class from PassBuilder in order to be able to access it from within the PassManager and avoid include conflicts.

Reviewed By: mtrofin

Differential Revision: https://reviews.llvm.org/D107025
2021-07-29 21:57:23 -07:00
Riccardo Mori
d5ee355f89 [Polly][Isl] Use isl::union_map::unite() instead of isl::union_map::add_map(). NFC
This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
 - Use `isl::union_map::unite()` instead of `isl::union_map::add_map()`
 - `isl-noexceptions.h` has been generated by this 3f43ae29fa

Depends on D106059

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D106061
2021-07-19 12:11:00 +02:00
Riccardo Mori
bad3ebbaae [Polly][Isl] Stop generating isl::union_{set,map} from isl::space. NFC
This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
 - Stop generating `isl::union_set` and isl::union_map` from `isl::space` and instead generate them from `isl::ctx`
 - Disable clang-format on `isl-noexceptions.h`
 - Removed `isl::union_{set,map}` generator from `isl::space` from `isl-noexceptions.h`
 - `isl-noexceptions.h` has been generated by this 87c3413b6f

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D106059
2021-07-19 11:24:53 +02:00
Riccardo Mori
0813bd1696 [Polly][Isl] Use isl::*::ctx instead of isl::*::get_ctx. NFC
This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
 - Use `isl::*::ctx()` instead of `isl::*::get_ctx()` (for example `isl::space::ctx()` instead of `isl::space::get_ctx()`)
 - Add `isl::` namespace in front of isl types to avoid confusion (for example `isl::space::ctx` and `isl::ctx`
 - `isl-noexceptions.h` has been generated by this b64e33c62d

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D105691
2021-07-09 21:14:14 +02:00
patacca
b55aedd0b8 [Polly][Isl] Use isl::union_set::unite() instead of isl::union_set::add_set(). NFC
This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
 - Use `isl::union_set::unite()` instead of `isl::union_set::add_set()`
 - `isl-noexceptions.h` has been generated by this 390c44982b

Depends on D104994

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D105444
2021-07-07 16:26:55 +02:00
patacca
f482497c38 [Polly][Isl] Use isl::set::tuple_dim, isl::map::domain_tuple_dim and isl::map::range_tuple_dim. NFC
This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
 - Use `isl::set::tuple_dim` instead of `isl::set::dim` and `isl::set::n_dim`
 - Use `isl::map::domain_tuple_dim` instead of `isl::map::dim`
 - Use `isl::map::range_tuple_dim` instead of `isl::map::dim`
 - isl-noexceptions.h has been generated by this 45576e1b42

Note that not all the usage of `isl::{set,map}::dim` where replaced

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D104994
2021-07-06 11:20:45 +02:00
patacca
cfe117def7 [Polly][Isl] Replacing isl method to_str() with stringFromIslObj(). NFC.
This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
 - Removing method `to_str()` from all the classes in the isl C++ bindings.
 - Overload method `stringFromIslObj()` so it accepts isl C++ objects.
 - To keep backward compatibility `stringFromIslObj()` now accepts a value that is returned if the isl C object is `null` or doesn't have a string representation (by default it's an empty string). In some cases it's better to have the string "null" instead of an empty string.
 - isl-noexceptions.h has been generated by this d33ec3a3bb

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D104211
2021-06-15 14:22:10 +02:00
patacca
7c7978a122 [Polly][Isl] Removing explicit operator bool() from isl C++ bindings. NFC.
This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
 - Removing explicit operator bool() from all the classes in the isl C++ bindings.
 - Replace each call to operator bool() to method `is_null()`.
 - isl-noexceptions.h has been generated by this 27396daac5

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D103976
2021-06-11 14:44:24 +02:00
Michael Kruse
a56bd7dec8 [Polly][Matmul] Re-pack A in every iteration.
Packed_A must be copied repeatedly, not just for the first iteration of
the outer tile.

This fixes llvm.org/PR50557
2021-06-09 15:19:52 -05:00
patacca
9b41d0958e [Polly][Isl] Removing nullptr constructor from C++ bindings. NFC.
[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC.

This is part of an effort to reduce the differences between the custom C++ bindings used right now by polly in `lib/External/isl/include/isl/isl-noxceptions.h` and the official isl C++ interface.

Changes made:
 - Removed `std::nullptr_t` constructor from all the classes in the isl C++ bindings.
 - `isl-noexceptions.h` has been generated by this a7e00bea38

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D103751
2021-06-08 23:46:28 +02:00
patacca
f60ea691a9 Revert "[Polly][Isl] Removing nullptr constructor from C++ bindings. NFC."
This reverts commit be5e2fc7bf781c7fc079943552ea1b519f45c815.

This introduced a building error for polly. https://lab.llvm.org/buildbot#builders/10/builds/4951
2021-06-08 17:12:10 +02:00