We previously had a different interpretation of unroll transformation
attributes than how LoopUnroll interpreted it. In particular,
llvm.loop.unroll.enable was needed explicitly to enable it and disabling
metadata was ignored.
Additionally, it required that either full unrolling or an unroll factor
to be specified or fail otherwise. An unroll factor is still required,
but the transformation is ignored with the hope that LoopUnroll is going
to apply the unrolling, since Polly currently does not implement an
heuristic.
Fixes llvm.org/PR50109
This produced a compile error with GCC:
llvm-project/polly/lib/Transform/ScheduleOptimizer.cpp:1220:49: error: cannot convert ‘bool’ to ‘llvm::TargetTransformInfo::RegisterKind’
1220 | RegisterBitwidth = TTI->getRegisterBitWidth(true);
We enumerated the cross product Domain x Scatter, but sorted only be the
scatter key. In case there are are multiple statement instances per
scatter value, the order between statement instances of the same loop
iteration was undefined.
Propertly enumerate and sort only by the scatter value, and group the
domains using the scatter dimension again.
Thanks to Leonard Chan for the report.
Make Polly look for unrolling metadata (https://llvm.org/docs/TransformMetadata.html#loop-unrolling) that is usually only interpreted by the LoopUnroll pass and apply it to the SCoP's schedule.
While not that useful by itself (there already is an unroll pass), it introduces mechanism to apply arbitrary loop transformation directives in arbitrary order to the schedule. Transformations are applied until no more directives are found. Since ISL's rescheduling would discard the manual transformations and it is assumed that when the user specifies the sequence of transformations, they do not want any other transformations to apply. Applying user-directed transformations can be controlled using the `-polly-pragma-based-opts` switch and is enabled by default.
This does not influence the SCoP detection heuristic. As a consequence, loop that do not fulfill SCoP requirements or the initial profitability heuristic will be ignored. `-polly-process-unprofitable` can be used to disable the latter.
Other than manually editing the IR, there is currently no way for the user to add loop transformations in an order other than the order in the default pipeline, or transformations other than the one supported by clang's LoopHint. See the `unroll_double.ll` test as example that clang currently is unable to emit. My own extension of `#pragma clang loop` allowing an arbitrary order and additional transformations is available here: https://github.com/meinersbur/llvm-project/tree/pragma-clang-loop. An effort to upstream this functionality as `#pragma clang transform` (because `#pragma clang loop` has an implicit transformation order defined by the loop pipeline) is D69088.
Additional transformations from my downstream pragma-clang-loop branch are tiling, interchange, reversal, unroll-and-jam, thread-parallelization and array packing. Unroll was chosen because it uses already-defined metadata and does not require correctness checks.
Reviewed By: sebastiankreutzer
Differential Revision: https://reviews.llvm.org/D97977
Regenerate the C++ wrapper header from the current isl version's
headers.
The most notable change is that some dimension sizes are represented by
an isl_size (instead of unsigned), which is a signed int. Additionally,
some function may return -1 in case of an error which already had been
fixed in the past. The C++ may no return -1 instead of UINT_MAX which
caused the problems.
Some types in Polly had been changed from unsigned to isl_size
(that were not already auto) and some loops/comparision had to be
changed to avoid unsigned/signed comparison warnings.
These are implementation details of the IslScheduleOptimizer pass
implementation and not use anywhere else. Hence, we can move them to the
cpp file and into an anonymous namespace.
Only getPartialTilePrefixes is, aside from the pass itself, used
externally (by the ScheduleOptimizerTest) and moved into the polly
namespace.
Move SimplifiyVisitor from Simplify.h to Simplify.cpp. It is not
relevant for applying the pass in either the NewPM or the legacyPM.
Rename it to SimplifyImpl to account for that.
This is possible due its state not being necessary to be preserved
between runs and thefore SimplifyImpl not needed to be held in the
pass object. Instead, SimplifyImpl is only instatiated for the
current Scop. In the NewPM as a function-local variable, and in the
legacy PM inside a llvm::Optional object because the state must be
preserved between the printScop (invoked by opt -analyze) and the most
recent runOnScop calls.
"using namespace" pollutes the namespace of every file that includes
such a header and universally considered a bad thing. Even the variant
namespace polly {
using namespace llvm;
}
(previously used by LoopGenerators.h) imports more symbols than the file
is in control of. The header may include a fixed set of files from LLVM,
but the header itself may by be included together with other headers
from LLVM. For instance, LLVM's MemorySSA.h and Polly's ScopInfo.h both
declare a class 'MemoryAccess' which may conflict.
Instead of prefixing everything in Polly's header files, this patch adds
'using' statements to import only the symbols that are actually
referenced in Polly. This approach is also used by MLIR to import
commonly used symbols into the mlir namespace.
This patch also puts the symbols declared in IslNodeBuilder.h into the
Polly namespace to also be able to use the imported symbols.
ZoneAlgorithms's computePHI relies on being provided with consistent a
schedule to compute the statement prodecessors of a statement containing
PHINodes. Otherwise unexpected results such as PHI nodes with multiple
predecessors can occur which would result in problems in the
algorithms expecting consistent data.
In the added test case, statement instances are scrubbed from the
SCoP their execution would result in undefined behavior (Due to a nsw
overflow). As already being undefined behavior in LLVM-IR, neither
AssumedContext nor InvalidContext are updated, giving computePHI no
means to avoid these cases.
Intoduce a new SCoP property, the DefinedBehaviorContext, that among
the runtime-checked conditions, also tracks the assumptions not needing
a runtime check, in particular those affecting the assumed control flow.
This replaces the manual combination of the 3 other contexts that was
already done in computePHI and setNewAccessRelation. Currently, the only
additional assumption is that loop induction variables will nsw flag for
not wrap, but potentially more can be added. Use in
hasFeasibleRuntimeContext, isl::ast_build and gisting are other
potential uses.
To limit computational complexity, the DefinedBehaviorContext is not
availabe if it grows too large (atm hardcoded to 8 disjuncts).
Possible other fixes include bailing out in computePHI when
inconsistencies are detected, choose an arbitrary value for inconsistent
cases (since it is undefined behavior anyways), or make the code
receiving the result from ComputePHI handle inconsistent data. All of
them reduce the quality of implementation having to bail out more often
and disabling the ability to assert on actually wrong results.
This fixes llvm.org/PR48783.
Declarations in headers should not be in the anonymous
namespace. Compilers also warn about the use of
<anon namespace>::SimplifyVisitor as a public field in
polly::SimplifyPass and polly::SimplifyPrinterPass.
Operand tree forwarding can cause the change of an access kind; in
particular change from a scalar kind to an array kind if the scalar
dependency is not necessary. Such an access cannot and doesn't need to
be forwarded anymore.
Fixes llvm.org/PR48034
Print to dbgs() any taken action.
Also, read-only scalars do not require any action unless
-polly-analyze-read-only-scalars=true is used. Better refect this by
using ForwardingAction::triviallyForwardable and thus not bumping the
statistics.
Recursively traversing the operand tree leads to an exponential blowup
if instructions are used multiple times due to every path leading to an
additional copy of the instructions after forwarding. This problem was
marked as a TODO in the code and was reported as a bug in llvm.org/PR47340.
Fix by caching already visited instructions and returning the cached
version when already visited. Instead of calling forwardTree() twice,
return a ForwardingAction structure that contains a lambda which will
carry-out the forwarding when requested. The lambdas are executed in
reverse-postorder to mimic the previous recursive calls unless there
is a reuse.
Fixes llvm.org/PR47340
VirtualUse of type UseKind::Inter expects the definition of a
llvm::Value to be represented in another statement. In the bug report
that statement has been removed due to its domain being empty.
Scop::InstStmtMap for the llvm::Value's defintion still pointed to the
removed statement, which resulted in the use-after-free.
The defintion statement was removed by Simplify because it was
considered to not be reachable by other uses; trivially because it is
never executed due to its empty domain. However, no such thing happend
to the using statement using the value altough its domain is also empty.
Fix by always removing statements with empty domains in Simplify since
these are not properly analyzable. A UseKind::Inter should always have a
statement with its defintion due to LLVM's SSA form.
Scop::removeStmtNotInDomainMap() also removes statements with empty
domains but does so without considering the context as used by
Simplify's analyzes.
In another angle, InstStmtMap pointing to removed statements should not
happen either and ForwardOpTree would have bailed out if the llvm::Value
definition was not represented by a statement. This will be corrected in
a followup-commit.
This fixes llvm.org/PR47098
The schedule of a fused loop has one isl_space per statement, such that
a conversion to a isl_map fails. However, the prevectorization is
interested in the schedule space only: Converting to the non-union
representation only after extracting the schedule range fixes the problem.
This fixes llvm.org/PR46578
The member LastSchedule was never set, such that printScop would always
print "n/a" instead of the last schedule.
To ensure that the isl_ctx lives as least as long as the stored
schedule, also store a shared_ptr.
Also set the schedule tree output style to ISL_YAML_STYLE_BLOCK to avoid
printing everything on a single line.
`opt -polly-opt-isl -analyze` will be used in the next commit.
../polly/lib/Transform/ScheduleOptimizer.cpp:812:54: warning: comparison of integers of different signs: 'isl_size' (aka 'int') and 'const unsigned int' [-Wsign-compare]
isl_schedule_node_band_n_member(Node.get()) >
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^
The primary motivation is to fix an assertion failure in
isl_basic_map_alloc_equality:
isl_assert(ctx, room_for_con(bmap, 1), return -1);
Although the assertion does not occur anymore, I could not identify
which of ISL's commits fixed it.
Compared to the previous ISL version, Polly requires some changes for this update
* Since ISL commit
20d3574 "perform parameter alignment by modifying both arguments to function"
isl_*_gist_* and similar functions do not always align the paramter
list anymore. This caused the parameter lists in JScop files to
become out-of-sync. Since many regression tests use JScop files with
a fixed parameter list and order, we explicitly call align_params to
ensure a predictable parameter list.
* ISL changed some return types to isl_size, a typedef of (signed) int.
This caused some issues where the return type was unsigned int before:
- No overload for std::max(unsigned,isl_size)
- It cause additional 'mixed signed/unsigned comparison' warnings.
Since they do not break compilation, and sizes larger than 2^31
were never supported, I am going to fix it separately.
* With the change to isl_size, commit
57d547 "isl_*_list_size: return isl_size"
also changed the return value in case of an error from 0 to -1. This
caused undefined looping over isl_iterator since the 'end iterator'
got index -1, never reached from the 'begin iterator' with index 0.
* Some internal changes in ISL caused the number of operations to
increase when determining access ranges to determine aliasing
overlaps. In one test, this caused exceeding the default limit of
800000. The operations-limit was disabled for this test.
This file lists every pass in LLVM, and is included by Pass.h, which is
very popular. Every time we add, remove, or rename a pass in LLVM, it
caused lots of recompilation.
I found this fact by looking at this table, which is sorted by the
number of times a file was changed over the last 100,000 git commits
multiplied by the number of object files that depend on it in the
current checkout:
recompiles touches affected_files header
342380 95 3604 llvm/include/llvm/ADT/STLExtras.h
314730 234 1345 llvm/include/llvm/InitializePasses.h
307036 118 2602 llvm/include/llvm/ADT/APInt.h
213049 59 3611 llvm/include/llvm/Support/MathExtras.h
170422 47 3626 llvm/include/llvm/Support/Compiler.h
162225 45 3605 llvm/include/llvm/ADT/Optional.h
158319 63 2513 llvm/include/llvm/ADT/Triple.h
140322 39 3598 llvm/include/llvm/ADT/StringRef.h
137647 59 2333 llvm/include/llvm/Support/Error.h
131619 73 1803 llvm/include/llvm/Support/FileSystem.h
Before this change, touching InitializePasses.h would cause 1345 files
to recompile. After this change, touching it only causes 550 compiles in
an incremental rebuild.
Reviewers: bkramer, asbirlea, bollu, jdoerfert
Differential Revision: https://reviews.llvm.org/D70211
lib/Transform/ScheduleOptimizer.cpp fails to compile on Solaris, both on the 9.x
branch (first noticed when running test-release.sh without -no-polly) and on trunk:
/var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/tools/polly/lib/Transform/ScheduleOptimizer.cpp: In function ‘MicroKernelParamsTy getMicroKernelParams(const llvm::TargetTransformInfo*, polly::MatMulInfoTy)’:
/var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/tools/polly/lib/Transform/ScheduleOptimizer.cpp:914:62: error: call of overloaded ‘sqrt(long unsigned int)’ is ambiguous
914 | ceil(sqrt(Nvec * LatencyVectorFma * ThroughputVectorFma) / Nvec) * Nvec;
| ^
In file included from /usr/gcc/9/lib/gcc/x86_64-pc-solaris2.11/9.1.0/include-fixed/math.h:24,
from /usr/gcc/9/include/c++/9.1.0/cmath:45,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/include/llvm-c/DataTypes.h:28,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/include/llvm/Support/DataTypes.h:16,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/include/llvm/ADT/Hashing.h:47,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/include/llvm/ADT/ArrayRef.h:12,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/tools/polly/include/polly/ScheduleOptimizer.h:12,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/tools/polly/lib/Transform/ScheduleOptimizer.cpp:48:
/usr/gcc/9/lib/gcc/x86_64-pc-solaris2.11/9.1.0/include-fixed/iso/math_iso.h:220:21: note: candidate: ‘long double std::sqrt(long double)’
220 | inline long double sqrt(long double __X) { return __sqrtl(__X); }
| ^~~~
/usr/gcc/9/lib/gcc/x86_64-pc-solaris2.11/9.1.0/include-fixed/iso/math_iso.h:186:15:
note: candidate: ‘float std::sqrt(float)’
186 | inline float sqrt(float __X) { return __sqrtf(__X); }
| ^~~~
/usr/gcc/9/lib/gcc/x86_64-pc-solaris2.11/9.1.0/include-fixed/iso/math_iso.h:74:15:
note: candidate: ‘double std::sqrt(double)’
74 | extern double sqrt __P((double));
| ^~~~
/var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/tools/polly/lib/Transform/ScheduleOptimizer.cpp:915:67:
error: call of overloaded ‘ceil(long unsigned int)’ is ambiguous
915 | int Mr = ceil(Nvec * LatencyVectorFma * ThroughputVectorFma / Nr);
| ^
In file included from /usr/gcc/9/lib/gcc/x86_64-pc-solaris2.11/9.1.0/include-fixed/math.h:24,
from /usr/gcc/9/include/c++/9.1.0/cmath:45,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/include/llvm-c/DataTypes.h:28,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/include/llvm/Support/DataTypes.h:16,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/include/llvm/ADT/Hashing.h:47,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/include/llvm/ADT/ArrayRef.h:12,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/tools/polly/include/polly/ScheduleOptimizer.h:12,
from /var/llvm/llvm-9.0.0-rc4/rc4/llvm.src/tools/polly/lib/Transform/ScheduleOptimizer.cpp:48:
/usr/gcc/9/lib/gcc/x86_64-pc-solaris2.11/9.1.0/include-fixed/iso/math_iso.h:196:21: note: candidate: ‘long double std::ceil(long double)’
196 | inline long double ceil(long double __X) { return __ceill(__X); }
| ^~~~
/usr/gcc/9/lib/gcc/x86_64-pc-solaris2.11/9.1.0/include-fixed/iso/math_iso.h:160:15:
note: candidate: ‘float std::ceil(float)’
160 | inline float ceil(float __X) { return __ceilf(__X); }
| ^~~~
/usr/gcc/9/lib/gcc/x86_64-pc-solaris2.11/9.1.0/include-fixed/iso/math_iso.h:76:15:
note: candidate: ‘double std::ceil(double)’
76 | extern double ceil __P((double));
| ^~~~
Fixed by adding casts to disambiguate, checked that it now compiles on both
amd64-pc-solaris2.11 and sparcv9-sun-solaris2.11 and on x86_64-pc-linux-gnu.
Differential Revision: https://reviews.llvm.org/D67442
llvm-svn: 371825
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.
Differential revision: https://reviews.llvm.org/D66259
llvm-svn: 368935
FunctionAnalysisManagerModuleProxy started to be used by the
AlwaysInlinerPass in r363287 and therefore had to be registered in the
New PassManager.
Should fix the regression tests
Polly :: ScopInliner/invariant-load-func.ll
Polly :: ScopInliner/simple-inline-loop.ll
llvm-svn: 363572
Extension nodes make schedule trees are less flexible: Many operations,
such as rescheduling, do not work on such schedule trees with extension.
As such, some functionality such as determining parallel loops in isl's
AST are disabled.
Currently, only the pattern-matching generalized matrix-matrix
multiplication optimization adds extension nodes (to add copy-in
statements).
This patch removes all extension nodes as the last step of the schedule
optimization by hoisting the extension node's added domain up to the
root domain node. All following passes can assume that schedule trees
work without restrictions, including the parallelism test. Mark the
outermost loop of the optimized matrix-matrix multiplication as parallel
such that -polly-parallel is able to parallelize that loop.
Differential Revision: https://reviews.llvm.org/D58202
llvm-svn: 362257
isl_map_from_union_map cannot determine the map's space if the union_map
is empty. polly::singleton was designed for this case. We pass the
expected map space to avoid crashing in isl_map_from_union_map.
This fixes an issue found by the aosp buildbot. Thanks to Eli Friedman
for the reproducer.
llvm-svn: 361290
PHI nodes (reads) could point to multiple instances of predecessor
blocks (PHI writes) when in an invalid context. Fix by removing PHI
instances that are in an invalid or ouside assumed context.
This fixes llvm.org/PR41656.
llvm-svn: 360454
This removes unused includes (and forward declarations) as
suggested by include-what-you-use. If a transitive include of a removed
include is required to compile a file, I added the required header (or
forward declaration if suggested by include-what-you-use).
This should reduce compilation time and reduce the number of iterative
recompilations when a header was changed.
llvm-svn: 357209
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
The main difference in this change is that isl_stat is now always
checked by default. As we elminiated most used of isl_stat, thanks to
Philip Pfaffe's implementation of foreach, only a small set of changes
is needed.
This change does not include the following recent changes to isl's C++
bindings:
- stricter error handling for isl_bool
- dropping of the isl::namespace qualifiers
The former requires a larger patch in Polly and consequently should go
through a patch-review. The latter will be applied in the next commit to
keep this commit free from noise.
We also still apply a couple of other changes on top of the official isl
bindings. This delta is expected to shrink over time.
llvm-svn: 338504
Michael Kruse