After the update to ISL to isl-0.22.1-87-gfee05a13 and its change of
isl_*_dim returning -1 instead of 0, the -1 got wrapped-around to
UINT_MAX because Polly often uses 'unsigned' type to represent
dimensions, as ISL did before this patch. This may happen in normal
executions after an out-of-quota.
Fix by catching the error-case earlier.
Summary:
This patch moves the getIndexExpressionsFromGEP function from polly
into ScalarEvolution so that both polly and DependenceAnalysis can
use it for the purpose of subscript delinearization when the array
sizes are not parametric.
Authored By: bmahjour
Reviewer: Meinersbur, sebpop, fhahn, dmgreen, grosser, etiotto, bollu
Reviewed By: Meinersbur
Subscribers: hiraditya, arphaman, Whitney, ppc-slack, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D73995
Simply dropping the createPollyIRBuilder() function here, because
it doesn't do much. Also directly initialize Expander in
ScopExpander instead of going through the copy-constructor.
The idiom
for (auto i = n - n; i < n; i += 1)
was intended to automatically derive the type of i from n
(signed/unsigned int) and avoid the 'mixed signed/unsigned comparison'
warning. However, almost-always-auto was never used in the LLVM coding
style (although we used it in Polly for some time) and I did never
intended to use this idiom upstream.
PVS Studio may warns about this idiom as 'warning: both sides of
operator are equivalent [misc-redundant-expression]'.
Remove the use of auto and directly use unsigned.
Also see http://llvm.org/PR44768
Scope of changes:
1) Moved RecordedAssumptions vector to ScopBuilder. RecordedAssumptions are used only for Scop constructions.
2) Moved definition of RecordedAssumptionsTy to ScopHelper. It is required both by ScopBuilder and SCEVAffinator.
3) Add new function recordAssumption to ScopHelper. One of its argument is a reference to RecordedAssumption vector. This function is used by ScopBuilder and SCEVAffinator.
4) All RecordedAssumptions are created by ScopBuilder. isl::pw_aff
objects for corresponding SCEVs are created inside ScopBuilder. Scop
functions do not record any assumptions. Scop can use isl::pw_aff
objects which were created by ScopBuilder.
5) Removed functions for handling RecordedAssumptions from Scop class.
6) Removed constness from getScopArrayInfo functions.
7) Replaced SCEVVisitor struct from SCEVAffinator with taylored version, which allow to pass pointer to RecordedAssumptions as function argument.
Differential Revision: https://reviews.llvm.org/D68056
There's quite a lot of references to Polly in the LLVM CMake codebase. However
the registration pattern used by Polly could be useful to other external
projects: thanks to that mechanism it would be possible to develop LLVM
extension without touching the LLVM code base.
This patch has two effects:
1. Remove all code specific to Polly in the llvm/clang codebase, replaicing it
with a generic mechanism
2. Provide a generic mechanism to register compiler extensions.
A compiler extension is similar to a pass plugin, with the notable difference
that the compiler extension can be configured to be built dynamically (like
plugins) or statically (like regular passes).
As a result, people willing to add extra passes to clang/opt can do it using a
separate code repo, but still have their pass be linked in clang/opt as built-in
passes.
Differential Revision: https://reviews.llvm.org/D61446
Scope of changes:
1. Moved buildSchedule functions to ScopBuilder.
2. Moved combineInSequence function to ScopBuilder.
3. Moved mapToDimension function to ScopBuilder.
4. Moved LoopStackTy to ScopBuilder.
5. Moved getLoopSurroundingScop to ScopHelper.
6. Moved getNumBlocksInLoop to ScopHelper.
7. Moved getNumBlocksInRegionNode to ScopHelper.
8. Moved getRegionNodeLoop to ScopHelper.
Differential Revision: https://reviews.llvm.org/D64223
llvm-svn: 366377
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
Compiling with -polly-target=hybrid was causing Polly to occur two times
in the pipeline. The reason was how the ManagedMemoryRewritePass was
registered in the pass manager. ManagedMemoryRewritePass being a
ModulePass was forcing all previous passes to get recomputed. This
commit avoids Polly to appear two times in the pipeline registering the
ManagedMemoryRewritePass later in the pass manager.
Patch by Lorenzo Chelini <l.chelini@icloud.com>
Differential Revision: https://reviews.llvm.org/D59263
llvm-svn: 356965
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
This removes the primary remaining API producing `TerminatorInst` which
will reduce the rate at which code is introduced trying to use it and
generally make it much easier to remove the remaining APIs across the
codebase.
Also clean up some of the stragglers that the previous mechanical update
of variables missed.
Users of LLVM and out-of-tree code generally will need to update any
explicit variable types to handle this. Replacing `TerminatorInst` with
`Instruction` (or `auto`) almost always works. Most of these edits were
made in prior commits using the perl one-liner:
```
perl -i -ple 's/TerminatorInst(\b.* = .*getTerminator\(\))/Instruction\1/g'
```
This also my break some rare use cases where people overload for both
`Instruction` and `TerminatorInst`, but these should be easily fixed by
removing the `TerminatorInst` overload.
llvm-svn: 344504
This is a bit awkward in a handful of places where we didn't even have
an instruction and now we have to see if we can build one. But on the
whole, this seems like a win and at worst a reasonable cost for removing
`TerminatorInst`.
All of this is part of the removal of `TerminatorInst` from the
`Instruction` type hierarchy.
llvm-svn: 340701
We upstreamed the export of isl_val_2exp, to the official cpp bindings.
In this process, we concluded that pow2 is a better and more widely used
name for this functionality. Hence, both the official isl-cpp bindings
and our derived variant use now the term pow2.
llvm-svn: 339312
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
Summary: This patch aims to provide support for detecting load patterns which are collectively invariant but right now `isHoistableLoad()` is checking each load instruction individually which cannot detect the load pattern as a whole.
Patch by: Sahil Girish Yerawar
Reviewers: bollu, philip.pfaffe, Meinersbur
Reviewed By: philip.pfaffe, Meinersbur
Differential Revision: https://reviews.llvm.org/D48026
llvm-svn: 335949
The number of SCEV expressions is usually linear in the number of IR
instructions being modeled. However, a naive SCEV visitor is not. For
an expression like x*x, "x" will be visited twice. If x is itself an
expression like x*x, that will be visited twice, etc, and the overall
runtime is O(2^N) in the number of SCEV expressions.
To prevent this from happening, add a cache, so we only visit each SCEV
expression once.
Not sure this is the best solution. Maybe we can instead check whether
the SCEV is scop-invariant (in which case we never need to map the
value). But we don't have a utility for that at the moment.
Differential Revision: https://reviews.llvm.org/D47087
llvm-svn: 335783
An assertion was not prepared to be passed a nullptr because the
out-of-quota limit was exceeded. Bail-out before the assertion
since the assertion does not apply on out-of-quote.
This fixes llvm.org/PR37477.
llvm-svn: 332488
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
Differential Revision: https://reviews.llvm.org/D44978
llvm-svn: 332352
nullptr is not a valid affine expression, and none of the callers check
for null, so we eventually hit an isl error and crash.
Instead, invalidate the scop and return a constant zero.
Differential Revision: https://reviews.llvm.org/D46445
llvm-svn: 332309
Add the switch -polly-debug-func to define the name of a debug
function. This function is ignored for any validity check.
Its purpose is to allow to observe a value after transformation by a
SCoP, and to follow which statements are executed in which order. For
instance, consider the following code:
static void dbg_printf(int sum, int i) {
fprintf(stderr, "The value of sum is %d, i=%d\n", sum, i);
fflush(stderr);
}
void func(int n) {
int sum = 0;
for (int i = 0; i < 16; i+=1) {
sum += i;
dbg_printf(sum, i);
}
}
Executing this after Polly's codegen with -polly-debug-func=dbg_printf
reveals the new execution order and the assumed values at that point of
execution.
Differential Revision: https://reviews.llvm.org/D45728
llvm-svn: 330466
Summary:
As of rL329273, LLVM has a mechanism to load new-pm plugins in opt. Use
this API in Polly.
Reviewers: grosser, Meinersbur, bollu
Reviewed By: grosser, Meinersbur
Subscribers: lksbhm, bollu, pollydev, llvm-commits
Differential Revision: https://reviews.llvm.org/D45484
llvm-svn: 330181
This patch removes the heuristic in
- Polly :: lib/Support/ScopHelper.cpp
The heuristic forces blocks that directly follow a loop header to not to be considered error blocks.
It was introduced in r249611 with the following commit message:
> This replaces the support for user defined error functions by a
> heuristic that tries to determine if a call to a non-pure function
> should be considered "an error". If so the block is assumed not to be
> executed at runtime. While treating all non-pure function calls as
> errors will allow a lot more regions to be analyzed, it will also
> cause us to dismiss a lot again due to an infeasible runtime context.
> This patch tries to limit that effect. A non-pure function call is
> considered an error if it is executed only in conditionally with
> regards to a cheap but simple heuristic.
In the code below `CCK_Abort2()` would be considered as an error block, but not `CCK_Abort1()` due to this heuristic.
```
for (int i = 0; i < n; i+=1) {
if (ErrorCondition1)
CCK_Abort1(); // No __attribute__((noreturn))
if (ErrorCondition2)
CCK_Abort2(); // No __attribute__((noreturn))
}
```
This does not seem useful. Checking error conditions in the beginning of some work is quite common. It causes a switch default-case to be not considered an error block in SPEC's cactuBSSN. The comment justifying the heuristic mentions a "load", which does not seem to be applicable here. It has been proposed to remove the heuristic.
In addition, the patch fixes the following test cases:
- Polly :: ScopDetect/mod_ref_read_pointer.ll
- Polly :: ScopInfo/max-loop-depth.ll
- Polly :: ScopInfo/mod_ref_access_pointee_arguments.ll
- Polly :: ScopInfo/mod_ref_read_pointee_arguments.ll
- Polly :: ScopInfo/mod_ref_read_pointer.ll
- Polly :: ScopInfo/mod_ref_read_pointers.ll
The test cases failed after removing the heuristic.
Differential Revision: https://reviews.llvm.org/D45274
Contributed-by: Lorenzo Chelini <l.chelini@icloud.com>
llvm-svn: 329548
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.
To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.
Reviewers: grosser, efriedma, jdoerfert, bollu, sebpop
Reviewed By: sebpop
Subscribers: sebpop, mehdi_amini, llvm-commits, pollydev
Tags: #polly
Differential Revision: https://reviews.llvm.org/D44361
llvm-svn: 327361
Piecewise affine expressions have directly corresponding mathematical
operators. Introduce these operators as overloads as this makes writing
code with isl::pw_aff expressions more directly readable.
We can now write:
A = B + C instead of A = B.add(C)
llvm-svn: 327216
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
In future, there will be no more a 1:1 correspondence between statements
and basic blocks, the name `contains` does not correctly capture their
relationship. A BB may infact comprise of multiple statements; hence we
describe a statement 'representing' a basic block.
Differential Revision: https://reviews.llvm.org/D35838
llvm-svn: 308982
This pass 'forwards' operand trees into statements that use them in
order to avoid scalar dependencies.
This minimal implementation handles only the case of speculatable
instructions. We will successively add support for:
- Hoisted loads
- Read-only values
- Synthesizable values
- Loads
- PHIs
- Forwarding only parts of the tree
Differential Revision: https://reviews.llvm.org/D35754
llvm-svn: 308825
Summary:
Added SPIR Code Generation to the PPCG Code Generator. This can be invoked using
the polly-gpu-arch flag value 'spir32' or 'spir64' for 32 and 64 bit code respectively.
In addition to that, runtime support has been added to execute said SPIR code on Intel
GPU's, where the system is equipped with Intel's open source driver Beignet (development
version). This requires the cmake flag 'USE_INTEL_OCL' to be turned on, and the polly-gpu-runtime
flag value to be 'libopencl'.
The transformation of LLVM IR to SPIR is currently quite a hack, consisting in part of regex
string transformations.
Has been tested (working) with Polybench 3.2 on an Intel i7-5500U (integrated graphics chip).
Reviewers: bollu, grosser, Meinersbur, singam-sanjay
Reviewed By: grosser, singam-sanjay
Subscribers: pollydev, nemanjai, mgorny, Anastasia, kbarton
Tags: #polly
Differential Revision: https://reviews.llvm.org/D35185
llvm-svn: 308751
Use a mark-and-sweep algorithm to find and remove unused instructions
and MemoryAccesses. This is useful in particular to remove scalar
writes that are never used anywhere. A scalar write in a loop induces
a write-after-write dependency that stops the loop iterations to be
rescheduled. Such writes can be a result of previous transformations
such as DeLICM and operand tree forwarding.
It adds a new class VirtualInstruction that represents an instruction in
a particular statement. At the moment an instruction can only belong to
the statement that represents a BasicBlock. In the future, instructions
can be in one of multiple statements representing a BasicBlock
(Nandini's work), in different statements than its BasicBlock would
indicate, and even multiple statements at once (by forwarding operand
trees). It also integrates nicely with the VirtualUse class.
ScopStmt::contains(Instruction*) currently uses the instruction's parent
BasicBlock to check whether it contains the instruction. It will need to
check the actual statement list when one of the aforementioned features
become possible.
Differential Revision: https://reviews.llvm.org/D35656
llvm-svn: 308626
We need to relax constraints on invariant loads so that they do not
create fake RAW dependences. So, we do not consider invariant loads as
scalar dependences in a region.
During these changes, it turned out that we do not consider `llvm::Value`
replacements correctly within `PPCGCodeGeneration` and `ISLNodeBuilder`.
The replacements dictated by `ValueMap` were not being followed in all
places. This was fixed in this commit. There is no clean way to decouple
this change because this bug only seems to arise when the relaxed
version of invariant load hoisting was enabled.
Differential Revision: https://reviews.llvm.org/D35120
llvm-svn: 307907
Summary:
Introduce a "hybrid" `-polly-target` option to optimise code for either the GPU or CPU.
When this target is selected, PPCGCodeGeneration will attempt first to optimise a Scop. If the Scop isn't modified, it is then sent to the passes that form the CPU pipeline, i.e. IslScheduleOptimizerPass, IslAstInfoWrapperPass and CodeGeneration.
In case the Scop is modified, it is marked to be skipped by the subsequent CPU optimisation passes.
Reviewers: grosser, Meinersbur, bollu
Reviewed By: grosser
Subscribers: kbarton, nemanjai, pollydev
Tags: #polly
Differential Revision: https://reviews.llvm.org/D34054
llvm-svn: 306863
ScopStmts were being used in the computation of the Domain of the SCoPs
in ScopInfo. Once statements are split, there will not be a 1-to-1
correspondence between Stmts and Basic blocks. Thus this patch avoids
the use of getStmtFor() by creating a map of BB to InvalidDomain and
using it to compute the domain of the statements.
Contributed-by: Nanidini Singhal <cs15mtech01004@iith.ac.in>
Differential Revision: https://reviews.llvm.org/D33942
llvm-svn: 306667
Summary:
The NVPTX backend is now initialised within Polly. A language front-end need not be modified to initialise the backend, just for Polly.
Reviewers: Meinersbur, grosser
Reviewed By: Meinersbur
Subscribers: vchuravy, mgorny
Tags: #polly
Differential Revision: https://reviews.llvm.org/D31859
llvm-svn: 306649
Michael Kruse