Commit Graph

1421 Commits

Author SHA1 Message Date
Roman Lebedev b4916918e5
[SCEV] SCEVPtrToIntExpr simplifications
If we've got an SCEVPtrToIntExpr(op), where op is not an SCEVUnknown,
we want to sink the SCEVPtrToIntExpr into an operand,
so that the operation is performed on integers,
and eventually we end up with just an `SCEVPtrToIntExpr(SCEVUnknown)`.

Reviewed By: mkazantsev

Differential Revision: https://reviews.llvm.org/D89692
2020-10-30 11:13:35 +03:00
Roman Lebedev 81fc53a36a
[SCEV] Introduce SCEVPtrToIntExpr (PR46786)
And use it to model LLVM IR's `ptrtoint` cast.

This is essentially an alternative to D88806, but with no chance for
all the problems it caused due to having the cast as implicit there.
(see rG7ee6c402474a2f5fd21c403e7529f97f6362fdb3)

As we've established by now, there are at least two reasons why we want this:
* It will allow SCEV to actually model the `ptrtoint` casts
  and their operands, instead of treating them as `SCEVUnknown`
* It should help with initial problem of PR46786 - this should eventually allow us
  to not loose pointer-ness of an expression in more cases

As discussed in [[ https://bugs.llvm.org/show_bug.cgi?id=46786 | PR46786 ]], in principle,
we could just extend `SCEVUnknown` with a `is ptrtoint` cast, because `ScalarEvolution::getPtrToIntExpr()`
should sink the cast as far down into the expression as possible,
so in the end we should always end up with `SCEVPtrToIntExpr` of `SCEVUnknown`.

But i think that it isn't the best solution, because it doesn't really matter
from memory consumption side - there probably won't be *that* many `SCEVPtrToIntExpr`s
for it to matter, and it allows for much better discoverability.

Reviewed By: mkazantsev

Differential Revision: https://reviews.llvm.org/D89456
2020-10-30 11:13:35 +03:00
Michael Kruse 7175cffb21 [Polly] Reuse multiple uses in operand tree.
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
2020-10-20 18:05:35 -05:00
Mark Schimmel 8e570abf10 Polly - specify address space when creating a pointer to a vector type
Polly incorrectly dropped the address space specified for a load instruction when it vectorized the code.

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D88907
2020-10-14 11:17:15 -05:00
Roman Lebedev 7ee6c40247
Revert "Reland "[SCEV] Model ptrtoint(SCEVUnknown) cast not as unknown, but as zext/trunc/self of SCEVUnknown"" and it's follow-ups
While we haven't encountered an earth-shattering problem with this yet,
by now it is pretty evident that trying to model the ptr->int cast
implicitly leads to having to update every single place that assumed
no such cast could be needed. That is of course the wrong approach.

Let's back this out, and re-attempt with some another approach,
possibly one originally suggested by Eli Friedman in
https://bugs.llvm.org/show_bug.cgi?id=46786#c20
which should hopefully spare us this pain and more.

This reverts commits 1fb6104293,
7324616660,
aaafe350bb,
e92a8e0c74.

I've kept&improved the tests though.
2020-10-14 16:09:18 +03:00
Roman Lebedev 1fb6104293
Reland "[SCEV] Model ptrtoint(SCEVUnknown) cast not as unknown, but as zext/trunc/self of SCEVUnknown"
This relands commit 1c021c64ca which was
reverted in commit 17cec6a11a because
an assertion was being triggered, since `BuildConstantFromSCEV()`
wasn't updated to handle the case where the constant we want to truncate
is actually a pointer. I was unsuccessful in coming up with a test case
where we'd end there with constant zext/sext of a pointer,
so i didn't handle those cases there until there is a test case.

Original commit message:

While we indeed can't treat them as no-ops, i believe we can/should
do better than just modelling them as `unknown`. `inttoptr` story
is complicated, but for `ptrtoint`, it seems straight-forward
to model it just as a zext-or-trunc of unknown.

This may be important now that we track towards
making inttoptr/ptrtoint casts not no-op,
and towards preventing folding them into loads/etc
(see D88979/D88789/D88788)

Reviewed By: mkazantsev

Differential Revision: https://reviews.llvm.org/D88806
2020-10-12 23:02:55 +03:00
Hans Wennborg 17cec6a11a Revert 1c021c64c "[SCEV] Model ptrtoint(SCEVUnknown) cast not as unknown, but as zext/trunc/self of SCEVUnknown"
> While we indeed can't treat them as no-ops, i believe we can/should
> do better than just modelling them as `unknown`. `inttoptr` story
> is complicated, but for `ptrtoint`, it seems straight-forward
> to model it just as a zext-or-trunc of unknown.
>
> This may be important now that we track towards
> making inttoptr/ptrtoint casts not no-op,
> and towards preventing folding them into loads/etc
> (see D88979/D88789/D88788)
>
> Reviewed By: mkazantsev
>
> Differential Revision: https://reviews.llvm.org/D88806

It caused the following assert during Chromium builds:

  llvm/lib/IR/Constants.cpp:1868:
  static llvm::Constant *llvm::ConstantExpr::getTrunc(llvm::Constant *, llvm::Type *, bool):
  Assertion `C->getType()->isIntOrIntVectorTy() && "Trunc operand must be integer"' failed.

See code review for a link to a reproducer.

This reverts commit 1c021c64ca.
2020-10-12 18:39:35 +02:00
Roman Lebedev 1c021c64ca
[SCEV] Model ptrtoint(SCEVUnknown) cast not as unknown, but as zext/trunc/self of SCEVUnknown
While we indeed can't treat them as no-ops, i believe we can/should
do better than just modelling them as `unknown`. `inttoptr` story
is complicated, but for `ptrtoint`, it seems straight-forward
to model it just as a zext-or-trunc of unknown.

This may be important now that we track towards
making inttoptr/ptrtoint casts not no-op,
and towards preventing folding them into loads/etc
(see D88979/D88789/D88788)

Reviewed By: mkazantsev

Differential Revision: https://reviews.llvm.org/D88806
2020-10-12 11:04:03 +03:00
Pengxuan Zheng deb00cf0b5 [Polly][NewPM] Port Simplify to the new pass manager
Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D87328
2020-09-20 19:18:01 -07:00
Michael Kruse 6983741eaa [Polly] Fix use-after-free.
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
2020-08-22 10:10:49 -05:00
Michael Kruse a54eb9b7c5 [Polly] Update isl to isl-0.22.1-416-g61d6dc75.
This fixes llvm.org/PR47104
2020-08-21 00:28:44 -05:00
Michael Kruse 1139d899d5 [polly] Unbreak buildbot.
The test failed since commit
bc10888dc "DomTree: Make PostDomTree indifferent to block successors swap"
which is a re-commit of
c35585e20 "DomTree: Make PostDomTree immune to block successors swap"
2020-08-06 21:17:27 -05:00
Wei Wang 46ebb619bf [FIX] Resolve test failure in polly/test/ScopInfo/memcpy-raw-source.ll
scoped-noalias -> scoped-noalias-aa

reference: https://reviews.llvm.org/D84542

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D84720
2020-07-28 09:15:40 -07:00
serge-sans-paille 515bc8c155 Harmonize Python shebang
Differential Revision: https://reviews.llvm.org/D83857
2020-07-16 21:53:45 +02:00
Michael Kruse c0bc995429 [Polly] Fix prevectorization of fused loops.
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
2020-07-10 16:42:03 -05:00
Michael Kruse 32bf468420 [Polly] Fix -polly-opt-isl -analyze
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.
2020-07-10 16:42:03 -05:00
Roman Lebedev a2619a60e4
Reland "[ScalarEvolution] createSCEV(): recognize `udiv`/`urem` disguised as an `sdiv`/`srem`"
This reverts commit d3e3f36ff1,
which reverter the original commit 2c16100e6f,
but with polly tests now actually passing.
2020-07-06 18:00:22 +03:00
Arthur Eubanks b210c9899b [BasicAA] Replace -basicaa with -basic-aa in polly
Follow up to https://reviews.llvm.org/D82607.
2020-06-30 15:50:17 -07:00
Simon Pilgrim 74dc081ef2 Update polly tests to use -disable-basicaa to -disable-basic-aa
These were missed in rG4cd19a6e15120cb
2020-06-27 15:56:01 +01:00
Eli Friedman f26bdb539e Make Value::getPointerAlignment() return an Align, not a MaybeAlign.
If we don't know anything about the alignment of a pointer, Align(1) is
still correct: all pointers are at least 1-byte aligned.

Included in this patch is a bugfix for an issue discovered during this
cleanup: pointers with "dereferenceable" attributes/metadata were
assumed to be aligned according to the type of the pointer.  This
wasn't intentional, as far as I can tell, so Loads.cpp was fixed to
stop making this assumption. Frontends may need to be updated.  I
updated clang's handling of C++ references, and added a release note for
this.

Differential Revision: https://reviews.llvm.org/D80072
2020-05-20 16:37:20 -07:00
Eli Friedman 1a6e4a2cf6 Fix polly tests after D79968. 2020-05-15 15:15:09 -07:00
Eli Friedman 4532a50899 Infer alignment of unmarked loads in IR/bitcode parsing.
For IR generated by a compiler, this is really simple: you just take the
datalayout from the beginning of the file, and apply it to all the IR
later in the file. For optimization testcases that don't care about the
datalayout, this is also really simple: we just use the default
datalayout.

The complexity here comes from the fact that some LLVM tools allow
overriding the datalayout: some tools have an explicit flag for this,
some tools will infer a datalayout based on the code generation target.
Supporting this properly required plumbing through a bunch of new
machinery: we want to allow overriding the datalayout after the
datalayout is parsed from the file, but before we use any information
from it. Therefore, IR/bitcode parsing now has a callback to allow tools
to compute the datalayout at the appropriate time.

Not sure if I covered all the LLVM tools that want to use the callback.
(clang? lli? Misc IR manipulation tools like llvm-link?). But this is at
least enough for all the LLVM regression tests, and IR without a
datalayout is not something frontends should generate.

This change had some sort of weird effects for certain CodeGen
regression tests: if the datalayout is overridden with a datalayout with
a different program or stack address space, we now parse IR based on the
overridden datalayout, instead of the one written in the file (or the
default one, if none is specified). This broke a few AVR tests, and one
AMDGPU test.

Outside the CodeGen tests I mentioned, the test changes are all just
fixing CHECK lines and moving around datalayout lines in weird places.

Differential Revision: https://reviews.llvm.org/D78403
2020-05-14 13:03:50 -07:00
Michael Kruse 1ef55ac96e [Polly] Fix long loop due to unsigned warparound.
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.
2020-04-27 12:15:56 -05:00
Eli Friedman 9b9454af8a Require "target datalayout" to be at the beginning of an IR file.
This will allow us to use the datalayout to disambiguate other
constructs in IR, like load alignment. Split off from D78403.

Differential Revision: https://reviews.llvm.org/D78413
2020-04-20 11:55:49 -07:00
Eli Friedman 89e0662dee Make IRBuilder automatically set alignment on load/store/alloca.
This is equivalent in terms of LLVM IR semantics, but we want to
transition away from using MaybeAlign to represent the alignment of
these instructions.

Differential Revision: https://reviews.llvm.org/D77984
2020-04-13 13:43:14 -07:00
Michael Kruse 4dded1a7cb [Polly] Add -polly-isl-arg command line option.
The option is passed as argv to ISL's command line option parser.

Polly's own own command line options take precedence over options passed
as `-polly-isl-arg`. For instance,
`-polly-isl-arg=--schedule-outer-coincidence` will be ignored in favor
of `-polly-opt-outer-coincidence`.

Reviewed By: grosser

Differential Revision: https://reviews.llvm.org/D77303
2020-04-06 08:56:57 -05:00
Yuanfang Chen 4ad7685258 Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`"""
This reverts commit 80a34ae311 with fixes.

Previously, since bots turning on EXPENSIVE_CHECKS are essentially turning on
MachineVerifierPass by default on X86 and the fact that
inline-asm-avx-v-constraint-32bit.ll and inline-asm-avx512vl-v-constraint-32bit.ll
are not expected to generate functioning machine code, this would go
down to `report_fatal_error` in MachineVerifierPass. Here passing
`-verify-machineinstrs=0` to make the intent explicit.
2020-02-13 10:16:06 -08:00
Yuanfang Chen 17122ec10a Revert "Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`""""
This reverts commit bb51d24330.
2020-02-13 10:08:05 -08:00
Yuanfang Chen bb51d24330 Revert "Revert "Reland "[Support] make report_fatal_error `abort` instead of `exit`"""
This reverts commit 80a34ae311 with fixes.

On bots llvm-clang-x86_64-expensive-checks-ubuntu and
llvm-clang-x86_64-expensive-checks-debian only,
llc returns 0 for these two tests unexpectedly. I tweaked the RUN line a little
bit in the hope that LIT is the culprit since this change is not in the
codepath these tests are testing.
llvm\test\CodeGen\X86\inline-asm-avx-v-constraint-32bit.ll
llvm\test\CodeGen\X86\inline-asm-avx512vl-v-constraint-32bit.ll
2020-02-13 10:02:53 -08:00
Michael Halkenhäuser 1e0be76e98 [Polly] LLVM OpenMP Backend -- Fix "static chunked" scheduling.
Static chunked OpenMP scheduling has not been treated correctly.
This patch fixes the problem that threads would not process their
(work-)chunks as intended.

Differential Revision: https://reviews.llvm.org/D61081
2020-02-11 12:51:35 -06:00
Michael Kruse e8227804ac [Polly] Update ISL to isl-0.22.1-87-gfee05a13.
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.
2020-02-10 19:03:08 -06:00
Eli Friedman 2f6b9edfa8 [AliasAnalysis] Add missing FMRB_* enums.
Previously, the enums didn't account for all the possible cases, which
could cause misleading results (particularly for a "switch" on
FunctionModRefBehavior).

Fixes regression in polly from recent patch to add writeonly to memset.

While I'm here, also fix a few dubious uses of the FMRB_* enum values.

Differential Revision: https://reviews.llvm.org/D73154
2020-01-28 15:47:08 -08:00
Eli Friedman d9e6196312 [polly] XFAIL memset_null.ll.
I'm working on a patch, but not sure how long it'll take.
2020-01-21 17:29:44 -08:00
serge_sans_paille 24ab9b537e Generalize the pass registration mechanism used by Polly to any third-party tool
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
2020-01-02 16:45:31 +01:00
Fangrui Song a36ddf0aa9 Migrate function attribute "no-frame-pointer-elim"="false" to "frame-pointer"="none" as cleanups after D56351 2019-12-24 16:27:51 -08:00
Fangrui Song 502a77f125 Migrate function attribute "no-frame-pointer-elim" to "frame-pointer"="all" as cleanups after D56351 2019-12-24 15:57:33 -08:00
Michael Kruse 7be6ec5fa2 [GPGPU] Fix regression test after 395124.
Commit 395124 "NVPTX: Don't insert an extra empty line at the end of the last section"
changed the length of the kernel payload. Update the regression test to the new binary size.
2019-11-13 06:20:17 +00:00
Michael Kruse d72637f5cc [ScopBuilder] Fix bug 38358 by preserving correct order of ScopStmts.
ScopBuilder::buildEqivClassBlockStmts creates ScopStmts for instruction
groups in basic block and inserts these ScopStmts into Scop::StmtMap,
however, as described in llvm.org/PR38358, comment #5, StmtScops are
inserted into vector ScopStmt[BB] in wrong order.  As a result,
ScopBuilder::buildSchedule creates wrong order sequence node.

Looking closer to code, it's clear there is no equivalent classes with
interleaving isOrderedInstruction(memory access) instructions after
joinOrderedInstructions.  Afterwards, ScopStmts need to be created and
inserted in the original order of memory access instructions, however,
at the moment ScopStmts are inserted in the order of leader instructions
which are probably not memory access instructions.

The fix is simple with a standalone loop scanning
isOrderedInstruction(memory access) instructions in basic block and
inserting elements into LeaderToInstList one by one.  The patch also
removes double reversing operations which are now unnecessary.

New test preserve-equiv-class-order-in-basic_block.ll is also added.

Differential Revision: https://reviews.llvm.org/D68941

llvm-svn: 375192
2019-10-17 23:55:35 +00:00
Tim Northover 1249126c7c Revert "Update polly test for SCEV change."
The motivating SCEV change was reverted as incorrect.

llvm-svn: 373185
2019-09-30 07:47:08 +00:00
Michael Kruse 241b02e762 [CodeGen] Handle outlining of CopyStmts.
Since the removal of extensions nodes from schedule trees in r362257 it
is possible to emit parallel code for SCoPs containing
matrix-multiplications. However, the code looking for references used in
outlined statement was not prepared to handle CopyStmts introduced by
the matrix-matrix multiplication detection.

In this case, CopyStmts do not introduce references in addition to the
ones captured by MemoryAccesses, i.e. we change the assertion to accept
CopyStmts and add a regression test for this case.

This fixes llvm.org/PR43164

llvm-svn: 372188
2019-09-17 22:59:43 +00:00
Michael Kruse 87baae85cd [ScopBuilder] Skip getting leader when merging statements to close holes.
Function joinOrderedInstructions merges instructions when a leader is encountered twice.
It also notices that leaders in SeenLeaders may lose their leadership in previous merging,
and tries to handle the case using following code:

    Instruction *PrevLeader = UnionFind.getLeaderValue(SeenLeaders.back());

However, this is wrong because it always gets leader for the last element of SeenLeaders,
and I believe it's wrong even we get leader for Prev here.  As a result, Statements in cases
like the one in patch aren't merged as expected.  After investigation, I believe it's
unnecessary to get leader instruction at all.  This is based on fact: Although leaders in
SeenLeaders could lose leadership, they only lose to others in SeenLeaders, in other words,
one existing leader will be chosen as new leader of merged equivalent statements.  We can
take advantage of this and simply check if current leader equals to Prev and break merging
if it does.

The patch also adds a new test.

Patch by bin.narwal <bin.narwal@gmail.com>

Differential Revision: https://reviews.llvm.org/D67007

llvm-svn: 371801
2019-09-13 01:04:38 +00:00
Michael Kruse cc0f0582c8 [Polly-ACC] Fix test after IR-printer change.
After r367755, even unnamed parameters are printed in IR dumps. Change
the test to expect te additional %0 in the line.

llvm-svn: 368763
2019-08-13 22:42:08 +00:00
Eli Friedman c68dd359ae Update polly test for SCEV change.
r366419 adds nsw to more SCEV expressions, which allows polly to
make more aggressive assumptions about the input expressions.

llvm-svn: 366510
2019-07-18 22:35:45 +00:00
Michael Kruse 88afd75300 [test] Add wrap flags after D61934.
https://reviews.llvm.org/D61934, committed as r362687, r363540, r363364
and r363147, made some emitted instruction nus/nsw. Add these falgs to
Polly's regression tests.

This should fix
    Polly :: Isl/CodeGen/partial_write_in_region_with_loop.ll
    Polly :: Isl/CodeGen/scev_expansion_in_nonaffine.ll

llvm-svn: 363599
2019-06-17 19:17:07 +00:00
Michael Kruse aa8a976174 [ScheduleOptimizer] Hoist extension nodes after schedule optimization.
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
2019-05-31 19:26:57 +00:00
Michael Kruse 467069688d [DeLICM] Use polly::singleton to allow empty result.
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
2019-05-21 19:18:26 +00:00
Michael Kruse c4c679c232 [CodeGen] Fix order of PHINode and MA Write generation.
At the end of a region statement, the PHINode must be generated
while the current IRBuilder's block is the region's exit node. For
obvious reasons: The PHINode references the region's exiting block.
A partial write would insert new control flow, i.e. insert new basic
blocks between the exiting blocks and the current block.

We fix this by generating the PHI nodes (region exit values) before
generating any MemoryAccess's stores.

This should fix the AOSP buildbot.

Reported-by: Eli Friedman <efriedma@quicinc.com>
llvm-svn: 361204
2019-05-20 22:31:09 +00:00
Eli Friedman 9b234b388d [Polly] Don't crash on invalid delinearization result.
In certain cases, it's possible for delinearization to decide one of the
array dimensions should be some function of an induction variable inside
the scop.  Make sure if this happens, we refuse to use those dimensions
for delinearization.

Usually, we end up rejecting the scop before it actually crashes, but it
looks like it's possible to slip past other checks in certain cases
involving smax expressions.

Fixes a crash that started showing up this week on the polly AOSP
builder.  As far as I can tell, this is a longstanding issue, though;
it was just exposed by better SCEV analysis of smin expressions.

Differential Revision: https://reviews.llvm.org/D61807

llvm-svn: 360708
2019-05-14 21:32:54 +00:00
Michael Kruse 2698390c68 [ZoneAlgo] Fix PHI inconsistency in invalid contexts.
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
2019-05-10 18:38:13 +00:00
Keno Fischer aa1b6f1cfb [polly][SCEV] Expand SCEV matcher cases for new smin/umin ops
These were added in rL360159, but I neglected to update polly at the
same time.

llvm-svn: 360238
2019-05-08 10:36:04 +00:00