Commit Graph

1958 Commits

Author SHA1 Message Date
Tobias Grosser d79cb0378b IRBuilder: Ensure we do not add empty map elements
Do not use "Map[Key] == nullptr" to check if a Key is in the map, but use
"Map.find(Key) == Map.end()". Map[Key] always adds Key into the map, a
side-effect we do not want.

Found by inspection. This is hard to test outside of a targetted unit test,
which seems too much overhead for this individual issue.

llvm-svn: 249544
2015-10-07 13:19:06 +00:00
Tobias Grosser 73725b8ba5 IRBuilder: Simplify code and reduce indention [NFC]
llvm-svn: 249543
2015-10-07 13:19:03 +00:00
Tobias Grosser 369c1d663b test: Add example of scalar that is reused accross loop
llvm-svn: 249527
2015-10-07 09:00:29 +00:00
David Blaikie ba2e4857b1 Fix configure checks when applied by the latest clang
Clang's been taught to warn on more things here (unused values when
calling pure functions and ignoring their result, for example).

It might be better to figure out how to have cmake compile these tests
without -Werror/without any warnings enabled. But this'll do for now & I
don't know enough about cmake to fix it any other way, or to understand
the tradeoffs in that space.

llvm-svn: 249472
2015-10-06 21:45:06 +00:00
Tobias Grosser 3593739cb2 IslAst: Give some hints why code generation might have been skipped
llvm-svn: 249427
2015-10-06 16:10:46 +00:00
Tobias Grosser 575aca8d43 Introduce -polly-process-unprofitable
This single option replaces -polly-detect-unprofitable and -polly-no-early-exit
and is supposed to be the only option that disables compile-time heuristics that
aim to bail out early on scops that are believed to not benefit from Polly
optimizations.

Suggested-by:  Johannes Doerfert
llvm-svn: 249426
2015-10-06 16:10:29 +00:00
Tobias Grosser f4ee371e60 tests: Drop -polly-detect-unprofitable and -polly-no-early-exit
These flags are now always passed to all tests and need to be disabled if
not needed. Disabling these flags, rather than passing them to almost all
tests, significantly simplfies our RUN: lines.

llvm-svn: 249422
2015-10-06 15:36:44 +00:00
Tobias Grosser 4fdcf7b813 test: By default disable Polly's compile-time profitability heuristics
llvm-svn: 249420
2015-10-06 15:30:26 +00:00
Tobias Grosser 935f62cf0d tests: Explicitly state if profitability tests should be used
Polly's profitability heuristic saves compile time by skipping trivial scops or
scops were we know no good optimization can be applied. For almost all our tests
this heuristic makes little sense as we aim for minimal test cases when testing
functionality. Hence, in almost all cases this heuristic is better be disabled.
In preparation of disabling Polly's compile time heuristic by default in the
test suite we first explicitly enable it in the couple of test cases that really
use it (or run with/without heuristic side-by-side).

llvm-svn: 249418
2015-10-06 15:19:35 +00:00
Tobias Grosser 1ac26d06fe test: Disable profitability heuristics to unfail LICM test case
This test case was XFAILed under the assumption Polly is unable to detect the
scop. However, disabling Polly's profitability heuristics is sufficient to
detect this scop.

llvm-svn: 249414
2015-10-06 15:10:19 +00:00
Tobias Grosser d76603fbe7 test: sdiv in loop bounds is supported since a while
By disabling our scop-profitability heuristics this becomes also visible in some
older test cases.

llvm-svn: 249411
2015-10-06 14:59:31 +00:00
Tobias Grosser b73c695aba tests: Drop outdated and unused lit variable
llvm-svn: 249401
2015-10-06 13:50:20 +00:00
Johannes Doerfert f17a78ef63 Remove non-executed statements during SCoP simplifcation
A statement with an empty domain complicates the invariant load
  hoisting and does not help any subsequent analysis or transformation.
  In fact it might introduce parameter dimensions or increase the
  schedule dimensionality. To this end, we remove statements with an
  empty domain early in the SCoP simplification.

llvm-svn: 249276
2015-10-04 15:00:05 +00:00
Johannes Doerfert 634909c2c9 [FIX] Domain generation for non-affine loops
llvm-svn: 249275
2015-10-04 14:57:41 +00:00
Johannes Doerfert f61df69423 [FIX] Count affine loops correctly
The "unprofitable" heuristic was broken and counted boxed loops
  even though we do not represent and optimize them.

llvm-svn: 249274
2015-10-04 14:56:08 +00:00
Johannes Doerfert 757a32b5b3 [FIX] Approximate non-affine loops correctly
Before isValidCFG() could hide the fact that a loop is non-affine by
  over-approximation. This is problematic if a subregion of the loop contains
  an exit/latch block and is over-approximated. Now we do not over-approximate
  in the isValidCFG function if we check loop control.  If such control is
  non-affine the whole loop is over-approximated, not only a subregion.

llvm-svn: 249273
2015-10-04 14:54:27 +00:00
Johannes Doerfert 30ffb6fcb6 [FIX] Check loop latches for valid control too.
This patch cannot be tested on its own as the isValidCFG currently
  hides the fact that control is actually non-affine with
  over-approximation. This will be corrected in the next patch and a
  test for non-affine latches will be added.

llvm-svn: 249272
2015-10-04 14:53:18 +00:00
Johannes Doerfert 8dba07770f [NFC] Remove unused classes
llvm-svn: 249271
2015-10-04 14:52:43 +00:00
Tobias Grosser d78616f98a Make ScopAnnotator a function-local variable to ensure it is freed at each run
When the ScopAnnotator was a class member variable some of the maps it contains
have not been properly cleared. As a result we had dangling pointers to
llvm::Value(s) which got detected by the AssertingVH we recently added.

No test case as this issue is hard to reproduce reliably as subsequent
optimizations need to delete some of the llvm::Values we still keep in our
lists.

llvm-svn: 249269
2015-10-04 11:19:13 +00:00
Tobias Grosser ecdfae6b15 IRBuilder: Use AssertingVH
llvm-svn: 249268
2015-10-04 10:18:56 +00:00
Tobias Grosser 5762b31df4 Use AssertingVH for ValueToValue Maps
By using AssertingVH we will see assertions in case Values to which still
pointers in our maps exists are deleted. This is very useful as we previously
had some bugs that were caused by such stale Value pointers.

llvm-svn: 249267
2015-10-04 10:18:49 +00:00
Tobias Grosser 2f1acac610 BlockGenerator: Use plain Value * instead of const Value *
The use of const qualified Value pointers prevents the use of AssertingVH. We
could probably think of adding const support to AssertingVH, but as const
correctness seems to currently provide limited benefit in Polly, we do not do
this yet.

llvm-svn: 249266
2015-10-04 10:18:45 +00:00
Tobias Grosser 9646e3fe4b BlockGenerators: Use auto to be less sensitive to type changes
llvm-svn: 249265
2015-10-04 10:18:39 +00:00
Tobias Grosser f4bb7a6a4d Consolidate the different ValueMapTypes we are using
There have been various places where llvm::DenseMap<const llvm::Value *,
llvm::Value *> types have been defined, but all types have been expected to be
identical. We make this more clear by consolidating the different types and use
BlockGenerator::ValueMapT wherever there is a need for types to match
BlockGenerator::ValueMapT.

llvm-svn: 249264
2015-10-04 10:18:32 +00:00
Tobias Grosser 1d45c6dadd IslExprBuilder: Use AssertingVH for IdToValueTy
llvm-svn: 249239
2015-10-03 17:20:00 +00:00
Tobias Grosser b28ee0fbb0 ScopInfo: Use AssertingVH in maps
By using asserting value handles, we will get assertions when we forget to clear
any of the Value maps instead of difficult to debug undefined behavior.

llvm-svn: 249238
2015-10-03 17:19:53 +00:00
Tobias Grosser e9cb5a0983 BlockGenerator: Use AssertingVH in maps
By using asserting value handles, we will get assertions when we forget to clear
any of the Value maps instead of difficult to debug undefined behavior.

llvm-svn: 249237
2015-10-03 17:19:49 +00:00
Michael Kruse afe0670863 Bail-out early if all statements have been simplified away
Treat the scop as invalid instead of creating dummy domains.

llvm-svn: 249151
2015-10-02 16:33:27 +00:00
Johannes Doerfert 3e7d171866 [FIX] Repair broken commit
The last invariant load fix was based on a later patch not
  polly/master, thus needs to be adjusted.

llvm-svn: 249145
2015-10-02 15:35:03 +00:00
Johannes Doerfert 8930f4846c [FIX] Do not hoist from inside a non-affine subregion
We have to skip accesses in non-affine subregions during hoisting as
  they might not be executed under the same condition as the entry of
  the non-affine subregion.

llvm-svn: 249139
2015-10-02 14:51:00 +00:00
Michael Kruse cac948ef46 Earlier creation of ScopStmt objects
This moves the construction of ScopStmt to the beginning of the 
ScopInfo pass. The late creation was a result of the earlier separation 
of ScopInfo and TempScopInfo. This will avoid introducing more 
ScopStmt-like maps in future commits. The AccFuncMap will also be 
removed in some future commit. DomainMap might also be included into 
ScopStmt.

The order in which ScopStmt are created changes and initially creates 
empty statements that are removed in a simplification.

Differential Revision: http://reviews.llvm.org/D13341

llvm-svn: 249132
2015-10-02 13:53:07 +00:00
Johannes Doerfert 911951f4f8 Hand down referenced & globally mapped values to the subfunction
If a value is globally mapped (IslNodeBuilder::ValueMap) and
  referenced in the code that will be put into a subfunction, we hand
  down the new value to the subfunction.

  This patch also removes code that handed down all invariant loads to
  the subfunction. Instead, only needed invariant loads are given to the
  subfunction. There are two possible reasons for an invariant load to
  be handed down:
    1) The invariant load is used in a block that is placed in the
       subfunction but which is not the parent of the load. In this
       case, the scalar access that will read the loaded value, will
       cause its base pointer (the preloaded value) to be handed down to
       the subfunction.
    2) The invariant load is defined and used in a block that is placed
       in the subfunction. With this patch we will hand down the
       preloaded value to the subfunction as the invariant load is
       globally mapped to that value.

llvm-svn: 249126
2015-10-02 13:11:27 +00:00
Johannes Doerfert 478a7de18b [NFC] Make the ScopDetection analysis a member of the Scop class
llvm-svn: 249125
2015-10-02 13:09:31 +00:00
Johannes Doerfert f56738041e Make the SCoP generation resistent wrt. error blocks
When error blocks are not terminated by an unreachable they have successors
  that might only be reachable via error blocks. Additionally, branches in
  error blocks are not checked during SCoP detection, thus we might not be able
  to handle them. With this patch we do not try to model error block exit
  conditions. Anything that is only reachable via error blocks is ignored too,
  as it will not be executed in the optimized version of the SCoP anyway.

llvm-svn: 249099
2015-10-01 23:48:18 +00:00
Johannes Doerfert f80f3b0449 Allow user defined error functions
The user can provide function names with
    -polly-error-functions=name1,name2,name3
  that will be treated as error functions. Any call to them is assumed
  not to be executed.

  This feature is mainly for developers to play around with the new
  "error block" feature.

llvm-svn: 249098
2015-10-01 23:45:51 +00:00
Johannes Doerfert 850d346302 [FIX] Parallel codegen for invariant loads
Hand down all preloaded values to the parallel subfunction.

llvm-svn: 249010
2015-10-01 13:40:36 +00:00
Johannes Doerfert e46925f324 [FIX] Erase stall results during the SCoP detection
With this patch we erase cached results for regions that are invalid
  as early as possible. If we do not (as before), it is possible that
  two expanded regions will have the same address and the tracked
  results for both are mixed. Currently this would "only" cause
  pessimism in later passes but that will change when we allow invariant
  loads in the SCoP.  Additionally, it triggers non-deterministic
  results as we might dismiss a later region because of results cached
  for an earlier one.

  There is no test case as the problem occurs only non-deterministically.

llvm-svn: 249000
2015-10-01 10:59:14 +00:00
Johannes Doerfert 47128f3af7 [FIX] Reintroduce an include needed to locally compile Polly
llvm-svn: 248947
2015-09-30 21:19:44 +00:00
Johannes Doerfert 59984322c3 [FIX] Handle identity mappings in the ScopExpander
If the VMap in the ScopExpander contains identity mappings
  we now ignore the mapping.

Reported-by: Tobias Grosser <tobias@grosser.es>
llvm-svn: 248946
2015-09-30 21:12:12 +00:00
Tobias Grosser fd9d07eac1 Drop unneeded includes
llvm-svn: 248937
2015-09-30 20:20:42 +00:00
Johannes Doerfert bb9387444c [FIX] Remove unknown variable
llvm-svn: 248926
2015-09-30 17:31:31 +00:00
Johannes Doerfert c0729a3216 Move remapping functionality in the ScopExpander
Because we handle more than SCEV does it is not possible to rewrite an
  expression on the top-level using the SCEVParameterRewriter only. With
  this patch we will do the rewriting on demand only and also
  recursively, thus not only on the top-level.

llvm-svn: 248916
2015-09-30 16:52:03 +00:00
Johannes Doerfert 6206d7a67c [FIX] Clear all maps between runs
llvm-svn: 248915
2015-09-30 16:51:05 +00:00
Tobias Grosser aff56c8a78 Reapply "BlockGenerator: Generate synthesisable instructions only on-demand"
Instructions which we can synthesis from a SCEV expression are not
generated directly, but only when they are used as an operand of
another instruction. This avoids generating unnecessary instructions
and works more reliably than first inserting them and then deleting
them later on.

This commit was reverted in r248860 due to a remaining miscompile, where
we forgot to synthesis the operand values that were referenced from scalar
writes. test/Isl/CodeGen/scalar-store-from-same-bb.ll tests that we do this
now correctly.

llvm-svn: 248900
2015-09-30 13:36:54 +00:00
Tobias Grosser 33cb9f9419 BlockGenerator: Extract value synthesis into its own function [NFC]
This will allow us to reuse this code in a subsequent commit.

llvm-svn: 248893
2015-09-30 11:56:19 +00:00
Johannes Doerfert ebfd72493c [NFC] Extract materialization of parameters
llvm-svn: 248882
2015-09-30 09:52:08 +00:00
Johannes Doerfert ef19ead20e [FIX] Use escape logic for invariant loads
Before we unconditinoally forced all users outside the SCoP to use
  the preloaded value. However, if the SCoP is not executed due to the
  runtime checks, we need to use the original value because it might not
  be invariant in the first place.

llvm-svn: 248881
2015-09-30 09:43:20 +00:00
Michael Kruse 76e924d31b Assign scop directly
This makes ScopInfo's scop member available earlier to other methods which will make some planned changes simpler.

No behavioral change intended

llvm-svn: 248879
2015-09-30 09:16:07 +00:00
Johannes Doerfert c1db67e218 Identify and hoist definitively invariant loads
As a first step in the direction of assumed invariant loads (loads
  that are not written in some context) we now detect and hoist
  definitively invariant loads. These invariant loads will be preloaded
  in the code generation and used in the optimized version of the SCoP.
  If the load is only conditionally executed the preloaded version will
  also only be executed under the same condition, hence we will never
  access memory that wouldn't have been accessed otherwise. This is also
  the most distinguishing feature to licm.

  As hoisting can make statements empty we will simplify the SCoP and
  remove empty statements that would otherwise cause artifacts in the
  code generation.

Differential Revision: http://reviews.llvm.org/D13194

llvm-svn: 248861
2015-09-29 23:47:21 +00:00
Johannes Doerfert f6343d74ef Revert "BlockGenerator: Generate synthesisable instructions only on-demand"
This reverts commit 07830c18d789ee72812d5b5b9b4f8ce72ebd4207.

  The commit broke at least one test in lnt,
    MultiSource/Benchmarks/Ptrdist/bc/number.c
  was miss compiled and the test produced a wrong result.

  One Polly test case that was added later was adjusted too.

llvm-svn: 248860
2015-09-29 23:43:40 +00:00
Tobias Grosser 81f005617e Replace default destructors by {} destructors
Hope this fixes the buildbots for now.

llvm-svn: 248823
2015-09-29 19:52:09 +00:00
Tobias Grosser 7dce3a60f2 Add default region generator
This hopefully helps to to address the following compile error on our buildbots

BlockGenerators.h:683:7: error: looser throw specifier for ‘virtual
polly::RegionGenerator::~RegionGenerator()’
BlockGenerators.h:164:11: error:   overriding ‘virtual polly::BlockGenerator::~BlockGenerator() noexcept
(true)`

llvm-svn: 248812
2015-09-29 18:07:17 +00:00
Tobias Grosser 98b3ee50ff Codegen: Support memory accesses with different types
Every once in a while we see code that accesses memory with different types,
e.g. to perform operations on a piece of memory using type 'float', but to copy
data to this memory using type 'int'. Modeled in C, such codes look like:

    void foo(float A[], float B[]) {
      for (long i = 0; i < 100; i++)
        *(int *)(&A[i]) = *(int *)(&B[i]);
      for (long i = 0; i < 100; i++)
        A[i] += 10;
    }

We already used the correct types during normal operations, but fall back to our
detected type as soon as we import changed memory access functions. For these
memory accesses we may generate invalid IR due to a mismatch between the element
type of the array we detect and the actual type used in the memory access.  To
address this issue, we always cast the newly created address of a memory access
back to the type of the memory access where the address will be used.

llvm-svn: 248781
2015-09-29 06:44:38 +00:00
David Blaikie 6163f67ad0 Remove unnecessary default dtor. The base dtor is already virtual and the derived dtor adds nothing.
llvm-svn: 248765
2015-09-29 00:12:50 +00:00
David Blaikie 8e9ea2a439 Make Polly -Wdeprecated clean by explicitly making BlockGenerator copy constructible
This is a bit of an awkward API and I'm not sure what the right solution
is. Having a publicly copy constructible base class makes it easy to
accidentally slice derived objects in a number of contexts.

llvm-svn: 248764
2015-09-29 00:00:29 +00:00
Tobias Grosser 95e59aaa54 OpenMP: Name addresses in subfunction structure
While debugging, this makes it easier to understand due to which memory
reference these stores have been introduced.

llvm-svn: 248717
2015-09-28 16:46:38 +00:00
Tobias Grosser 28b9a14b07 BlockGenerator: Generate synthesisable instructions only on-demand
Instructions which we can synthesis from a SCEV expression are not generated
directly, but only when they are used as an operand of another instruction. This
avoids generating unnecessary instruction and works more reliably than first
inserting them and then deleting them later on.

Suggested-by: Johannes Doerfert <doerfert@cs.uni-saarland.de>

Differential Revision: http://reviews.llvm.org/D13208

llvm-svn: 248712
2015-09-28 13:47:50 +00:00
Michael Kruse 5c0f97d537 Improve comments related to MemoryAccess::MemoryOrigin; NFC
llvm-svn: 248705
2015-09-28 10:06:50 +00:00
Johannes Doerfert 58a7c75c86 [NFC] Add accidentally removed comment line
llvm-svn: 248704
2015-09-28 09:48:53 +00:00
Johannes Doerfert 9a132f36c3 Allow switch instructions in SCoPs
This patch allows switch instructions with affine conditions in the
  SCoP. Also switch instructions in non-affine subregions are allowed.
  Both did not require much changes to the code, though there was some
  refactoring needed to integrate them without code duplication.

  In the llvm-test suite the number of profitable SCoPs increased from
  135 to 139 but more importantly we can handle more benchmarks and user
  inputs without preprocessing.

Differential Revision: http://reviews.llvm.org/D13200

llvm-svn: 248701
2015-09-28 09:33:22 +00:00
Tobias Grosser f223cdf17e [tests] Add memory writes to make this scop not trivially empty
llvm-svn: 248697
2015-09-28 07:37:06 +00:00
Johannes Doerfert f32f5f2305 Remove obsolete check
This check was needed at some point but seems not useful anymore. Only
  one adjustment in the domain generation was needed to cope with the
  cases this check prevented from happening before.

llvm-svn: 248695
2015-09-28 01:30:37 +00:00
Johannes Doerfert 91ad092bb2 [NFC] Remove unused SCoP diagnostic
llvm-svn: 248694
2015-09-28 01:29:44 +00:00
Tobias Grosser 0722a1e5d5 BlockGenerator: Be less agressive with deleting dead instructions
We now only delete trivially dead instructions in the BB we copy (copyBB), but
not in any other BB.  Only for copyBB we know that there will _never_ be any
future uses of instructions that have no use after copyBB has been generated.
Other instructions in the AST that have been generated by IslNodeBuilder may
look dead at the moment, but may possibly still be referenced by GlobalMaps. If
we delete them now, later uses would break surprisingly.

We do not have a test case that breaks due to us deleting too many instructions.
This issue was found by inspection.

llvm-svn: 248688
2015-09-27 19:50:16 +00:00
Tobias Grosser a43b6e935c Drop unused variable
llvm-svn: 248687
2015-09-27 17:54:50 +00:00
Johannes Doerfert 45be64464b [NFC] Consistenly use commented and annotated ScopPass functions
The changes affect methods that are part of the Pass interface and
  include:
    - Comments that describe the methods purpose.
    - A consistent use of the keywords override and virtual.
  Additionally, the printScop method is now optional and removed from
  SCoP passes that do not implement it.

llvm-svn: 248685
2015-09-27 15:43:29 +00:00
Johannes Doerfert 0f37630849 [NFC] Use releaseMemory to release internal memory
llvm-svn: 248684
2015-09-27 15:42:28 +00:00
Tobias Grosser 0ff79e586d BlockGenerator: Simplify code generated for region statements
After having generated a new user statement a couple of inefficient or
trivially dead instructions may remain. This commit runs instruction
simplification over the newly generated blocks to ensure unneeded
instructions are removed right away.

This commit does adds simplification for non-affine subregions which was not
yet part of 248681.

llvm-svn: 248683
2015-09-27 11:35:00 +00:00
Tobias Grosser 412f9774f8 [CodeGen test] Replace undef values with some defined constants
Otherwise, part of the computation will be just simplified away when we add
instruction simplification support to the RegionGenerator.

llvm-svn: 248682
2015-09-27 11:34:53 +00:00
Tobias Grosser 1b9d25a42d BlockGenerator: Simplify code generated for scop statements
After having generated a new user statement a couple of inefficient or trivially
dead instructions may remain. This commit runs instruction simplification over
the newly generated blocks to ensure unneeded instructions are removed right
away.

This commit does not yet add simplification for non-affine subregions.

llvm-svn: 248681
2015-09-27 11:17:22 +00:00
Johannes Doerfert 284e67828f [NFC] Remove obsolete member
llvm-svn: 248675
2015-09-26 20:58:29 +00:00
Johannes Doerfert fb19dd694c Create parallel code in a separate block
This commit basically reverts r246427 but still solves the issue
  tackled by that commit. Instead of emitting initialization code in the
  beginning of the start block we now generate parallel code in its own
  block and thereby guarantee separation. This is necessary as we cannot
  generate code for hoisted loads prior to the start block but it still
  needs to be placed prior to everything else.

llvm-svn: 248674
2015-09-26 20:57:59 +00:00
Michael Kruse caac2b6930 Fix typo
llvm-svn: 248670
2015-09-26 15:51:44 +00:00
Tobias Grosser 06c495c2b0 Add test case from llvm.org/PR17187
The new domain construction algorithm now correctly models this test case (and
derives an empty run-time condition). Add this test case to ensure we do not
regress.

llvm-svn: 248669
2015-09-26 14:27:54 +00:00
Johannes Doerfert 12155a9ef4 Add test case from open bug
The bug (15771) was fixed already with the new domain generation
  but the test case was not added till now.

llvm-svn: 248668
2015-09-26 14:03:29 +00:00
Johannes Doerfert c6987c18de [FIX] Use the surrounding loop for non-affine SCoP regions
When the whole SCoP is a non-affine region we need to use the
  surrounding loop in the construction of the schedule as that is
  the one that will be looked up after the schedule generation.

  This fixes bug 24947

llvm-svn: 248667
2015-09-26 13:41:43 +00:00
Tobias Grosser bbda083c75 Add test case for delinearization through bitcasts
This was forgotten in r247928

llvm-svn: 248663
2015-09-26 08:55:59 +00:00
Tobias Grosser 99c70dd8d1 Ensure memory accesses to the same array have identical dimensionality
When recovering multi-dimensional memory accesses, it may happen that different
accesses to the same base array are recovered with different dimensionality.
This patch ensures that the dimensionalities are unified by adding zero valued
dimensions to acesses with lower dimensionality. When starting to model
fixed-size arrays as multi-dimensional in 247906, this has not been taken
care of.

llvm-svn: 248662
2015-09-26 08:55:54 +00:00
Michael Kruse 8d0b734e71 Let MemoryAccess remember its purpose
There are three possible reasons to add a memory memory access: For explicit load and stores, for llvm::Value defs/uses, and to emulate PHI nodes (the latter two called implicit accesses). Previously MemoryAccess only stored IsPHI. Register accesses could be identified through the isScalar() method if it was no IsPHI. isScalar() determined the number of dimensions of the underlaying array, scalars represented by zero dimensions.

For the work on de-LICM, implicit accesses can have more than zero dimensions, making the distinction of isScalars() useless, hence now stored explicitly in the MemoryAccess. Instead, we replace it by isImplicit() and avoid the term scalar for zero-dimensional arrays as it might be confused with llvm::Value which are also often referred to as scalars (or alternatively, as registers).

No behavioral change intended, under the condition that it was impossible to create explicit accesses to zero-dimensional "arrays".

llvm-svn: 248616
2015-09-25 21:21:00 +00:00
Michael Kruse 33d6c0bbc5 Use per-Purpose overloads for MemoryAccess creation
This makes the intent of each created object clearer and allows to add more specific asserts. The bug fixed in r248535 has been discovered this way.

No functional change intended; everything should behave as before.

llvm-svn: 248603
2015-09-25 18:53:27 +00:00
Tobias Grosser c90ed44b31 [cmake] terminate isl/stdint.h with a newline
This avoids warnings of the form:
  stdint.h:1:20: warning: no newline at end of file [-Wnewline-eof]

llvm-svn: 248570
2015-09-25 11:45:26 +00:00
Tobias Grosser c2bb0cbe00 Sort includes using Chandler's sort_includes.py script
llvm-svn: 248568
2015-09-25 09:49:19 +00:00
Tobias Grosser 8016f3a4f5 Add missing PHI to test case
llvm-svn: 248563
2015-09-25 05:41:30 +00:00
Tobias Grosser da95a4a7c7 Handle read-only scalars used in PHI-nodes correctly
This change addresses three issues:

  - Read only scalars that enter a PHI node through an edge that comes from
    outside the scop are not modeled any more, as such PHI nodes will always
    be initialized to this initial value right before the SCoP is entered.
  - For PHI nodes that depend on a scalar value that is defined outside the
    scop, but where the scalar values is passed through an edge that itself
    comes from a BB that is part of the region, we introduce in this basic
    block a read of the out-of-scop value to ensure it's value is available
    to write it into the PHI alloc location.
  - Read only uses of scalars by PHI nodes are ignored in the general read only
    handling code, as they are taken care of by the general PHI node modeling
    code.

llvm-svn: 248535
2015-09-24 20:59:59 +00:00
Michael Kruse 26ed65e00d Fix comparison signed/unsigned mismatch warning; NFC
llvm-svn: 248520
2015-09-24 17:32:49 +00:00
Tobias Grosser 2553ebc79d Mark a couple of issues as done
llvm-svn: 248492
2015-09-24 14:30:14 +00:00
Michael Kruse b280ded108 Rename Polly_isl to PollyISL
Library names in the LLVM framework usually do not contain underscores.

llvm-svn: 248487
2015-09-24 12:38:49 +00:00
Michael Kruse 2d0ece960f Remove Analysis Output of TempScopInfo
After the merge of TempScopInfo into ScopInfo the analysis output 
remained because of the existing unit tests. These remains are removed 
and the units tests converted to match the equivalent output of 
ScopInfo's analysis output. The unit tests are also moved into the
directory of ScopInfo tests.

Differential Revision: http://reviews.llvm.org/D13116

llvm-svn: 248485
2015-09-24 11:41:21 +00:00
Michael Kruse 519b3cfd27 Compile ISL into its own library
Refactor all ISL-related cmake build instructions into its own 
CMakeLists.txt and build as a separate library.

This is useful to apply ISL-related build flags to ISL only and not to 
Polly's files. Also, it the separation of both projects becomes clearer.

Proposed name of the library is Polly_isl. It is not "isl" to avoid 
mix-up with potentially installed libisl.{a|so}.

Tested configurations:
- Windows with cmake 3.2
- Ubuntu with cmake 3.0.2 
- Ubuntu with cmake 3.0.2  BUILD_SHARED_LIBS on
- Ubuntu with cmake 2.8.12.2 (LLVM minimum version)
- Ubuntu out-of-LLVM-tree

Differential Revision: http://reviews.llvm.org/D12810

llvm-svn: 248484
2015-09-24 11:30:22 +00:00
Johannes Doerfert e526de5a47 Make MIN_LOOP_TRIP_COUNT a static constant
llvm-svn: 248192
2015-09-21 19:10:11 +00:00
Tobias Grosser b1c39429d9 Do not model delinearized and linearized access relation for a single access
A missing return statement that previously did not have a visibly negative
effect caused after some data-structure changes in r248024 multi-dimensional
accesses to be modeled both multi-dimensional as well as linearized. This
commit adds the missing return to avoid the incorrect double modeling as
well as the compile time increases it caused.

llvm-svn: 248171
2015-09-21 16:19:25 +00:00
Johannes Doerfert 6a72a2af13 Use <nsw> AddRecs in the affinator to avoid bounded assumptions
If we encounter a <nsw> tagged AddRec for a loop we know the trip count of
  that loop has to be bounded or the semantics is undefined anyway. Hence, we
  only need to add unbounded assumptions if no such AddRec is known.

llvm-svn: 248128
2015-09-20 16:59:23 +00:00
Johannes Doerfert 707a406078 Add bounded loop assumption
So far we ignored the unbounded parts of the iteration domain, however
  we need to assume they do not occure at all to remain sound if they do.

llvm-svn: 248126
2015-09-20 16:38:19 +00:00
Johannes Doerfert f2cc86edae Simplify domain generation
We now add loop carried information during the second traversal of the
  region instead of in a intermediate step in-between. This makes the
  generation simpler, removes code and should even be faster.

llvm-svn: 248125
2015-09-20 16:15:32 +00:00
Johannes Doerfert 0c1123a831 [FIX] Repair test case that was unprofitable
llvm-svn: 248124
2015-09-20 16:14:41 +00:00
Johannes Doerfert 06c57b594c Allow loops with multiple back edges
In order to allow multiple back edges we:
    - compute the conditions under which each back edge is taken
    - build the union over all these conditions, thus the condition that
      any back edge is taken
    - apply the same logic to the union we applied to a single back edge

llvm-svn: 248120
2015-09-20 15:00:20 +00:00
Johannes Doerfert 7175bdfbe4 Add loop trip count based heuristic for SCoP detection
As we currently do not perform any optimizations that targets (or is
  even aware) small trip counts we will skip them when we count the
  loops in a region.

llvm-svn: 248119
2015-09-20 14:56:54 +00:00
Johannes Doerfert b276bde162 [NFC] Remove obsolete diagnostic for unstructured control flow
llvm-svn: 248118
2015-09-20 14:55:50 +00:00
Michael Kruse 84f70acd68 Remove unused variable Dimension [NFC]
llvm-svn: 248026
2015-09-18 20:03:32 +00:00
Michael Kruse e2bccbbfb2 Merge IRAccess into MemoryAccess
All MemoryAccess objects will be owned by ScopInfo::AccFuncMap which 
previously stored the IRAccess objects. Instead of creating new 
MemoryAccess objects, the already created ones are reused, but their 
order might be different now. Some fields of IRAccess and MemoryAccess 
had the same meaning and are merged.

This is the last step of fusioning TempScopInfo.{h|cpp} and 
ScopInfo.{h.cpp}. Some refactoring might still make sense.

Differential Revision: http://reviews.llvm.org/D12843

llvm-svn: 248024
2015-09-18 19:59:43 +00:00
Tobias Grosser b09455dee0 Store EscapeMap as Value* instead of AllocInst
This currently does not change the behavior in Polly, but it allows us to later
also overwrite the EscapeMap with our GlobalMap.

llvm-svn: 247970
2015-09-18 06:01:11 +00:00
Tobias Grosser 6f36d9ab01 Delinearize multi-dimensional arrays through bitcasts
In some cases instcombine introduces bitcasts that slightly obfuscate the
multi-dimensionality of an array. This patch teaches our fixed-size
delinearization how to look through bitcasts.

llvm-svn: 247928
2015-09-17 20:16:21 +00:00
Tobias Grosser 0537f41de5 Do not use the assumed context in the dependence analysis any more
This information is implicitly available through the multi-dimensionality of
memory accesses. This reduces compile time for 3mm from 430ms to 400ms and
should generally benefit compile time for cases where the assumed context
is complex.

llvm-svn: 247907
2015-09-17 17:28:19 +00:00
Tobias Grosser 5fd8c0961e Model fixed-size multi-dimensional arrays if possible multi-dimensional
If the GEP instructions give us enough insights, model scalar accesses as
multi-dimensional (and generate the relevant run-time checks to ensure
correctness). This will allow us to simplify the dependence computation in
a subsequent commit.

llvm-svn: 247906
2015-09-17 17:28:15 +00:00
Tobias Grosser faf8f6f62e Extract function that derives the index expressions of a GEP instruction [NFC]
We currently use this functionality to add run-time assumptions that check its
in-bound property.

llvm-svn: 247893
2015-09-17 15:47:52 +00:00
Tobias Grosser e375d8058a Add option to enable/disable reduction usage in dependence analysis
llvm-svn: 247781
2015-09-16 09:50:17 +00:00
Johannes Doerfert 883f8c1d2f Use modulo semantic to generate non-integer-overflow assumptions
This will allow to generate non-wrap assumptions for integer expressions
  that are part of the SCoP. We compare the common isl representation of
  the expression with one computed with modulo semantic. For all parameter
  combinations they are not equal we can have integer overflows.

  The nsw flags are respected when the modulo representation is computed,
  nuw and nw flags are ignored for now.

  In order to not increase compile time to much, the non-wrap assumptions
  are collected in a separate boundary context instead of the assumed
  context. This helps compile time as the boundary context can become
  complex and it is therefor not advised to use it in other operations
  except runtime check generation. However, the assumed context is e.g.,
  used to tighten dependences. While the boundary context might help to
  tighten the assumed context it is doubtful that it will help in practice
  (it does not effect lnt much) as the boundary (or no-wrap assumptions)
  only restrict the very end of the possible value range of parameters.

  PET uses a different approach to compute the no-wrap context, though lnt runs
  have shown that this version performs slightly better for us.

llvm-svn: 247732
2015-09-15 22:52:53 +00:00
Johannes Doerfert cef616fe2d Use blocks instead of domains in SCEVAffinator
Due to the new domain generation, the SCoP keeps track of the domain
  for all blocks, thus the SCEVAffinator can now work with blocks to avoid
  duplication of the domains.

llvm-svn: 247731
2015-09-15 22:49:04 +00:00
Johannes Doerfert b20f151d56 Coalesce the constructed domains early
llvm-svn: 247728
2015-09-15 22:11:49 +00:00
Michael Kruse da8d6203f4 Fix after renamed CMake cache entry
LLVM_EXTERNAL_CLANG_BUILD was changed to LLVM_TOOL_CLANG_BUILD in
r242059.

llvm-svn: 247675
2015-09-15 10:51:15 +00:00
Michael Kruse fa62b1763c Run polly-check-format with unit tests
Add polly-check-format as dependency of check-polly if clang-format is 
available in the same build.

Differential Revision: http://reviews.llvm.org/D12850

llvm-svn: 247600
2015-09-14 19:11:48 +00:00
Michael Kruse 69f3788c36 Revise polly-{update|check}-format targets
Summary:
Make clang-format run on each file independently using
add_custom_format (instead using a shell script in utils/). The targets
polly-{update|check}-format depend on these.

The primary motivation is to make them work on Windows, but also
improves them generally:
- Each file update/check can run in parallel (Although they do not take
  long to run anyway)
- Implicit dependency on clang-format, so it recompiles if necessary
- polly-check-format shows the formatting difference if failing

Differential Revision: http://reviews.llvm.org/D12837

llvm-svn: 247581
2015-09-14 16:59:50 +00:00
Michael Kruse 2846877d88 Replace some SmallVector-typed parameters by ArrayRef
ArrayRef avoids making implementation details such as the number of stack elements to be part of the function signature.

llvm-svn: 247572
2015-09-14 15:45:33 +00:00
Tobias Grosser aaadc5302c [test] Load Polly before using the polly flags
llvm-svn: 247551
2015-09-14 11:49:05 +00:00
Johannes Doerfert 334f9e87c6 [FIX] XFAIL test that depends on pending LLVM commit
llvm-svn: 247550
2015-09-14 11:45:34 +00:00
Tobias Grosser 0b13890042 Fix formatting
llvm-svn: 247549
2015-09-14 11:38:06 +00:00
Johannes Doerfert e114dc024e [FIX] Handle error blocks in non-affine regions correctly
llvm-svn: 247545
2015-09-14 11:15:58 +00:00
Johannes Doerfert 40fa56f59f [FIX] Allow the whole SCoP to be a non-affine subregion
llvm-svn: 247544
2015-09-14 11:15:07 +00:00
Johannes Doerfert 36255eecd8 Revert r247278 "Disable support for modulo expressions"
This reverts commit 00c5b6ca8832439193036aadaaaee92a43236219.

  We can handle modulo expressions in the domain again.

llvm-svn: 247542
2015-09-14 11:14:23 +00:00
Johannes Doerfert ca1e38fa43 Propagate exit conditions as described in the PET paper
At some point we build loop trip counts using this method. It was replaced by
  a simpler trick that works only for affine (e.g., not modulo) constraints and
  relies on the removal of unbounded parts. In order to allow modulo constrains
  again we go back to the former, more accurate method.

llvm-svn: 247540
2015-09-14 11:12:52 +00:00
Michael Kruse 9d08009dff Merge TempScop into Scop
Summary:
TempScop is basically a holder for AccFuncMap, the dictionary from BasicBlocks to IRAccess lists. We move the list into polly::Scop and remove the polly::TempScop class.

There is one small change in behavior: If ScopInfo finds that its AssumedContext is impossible, it bails out by deleting the Scop object. The TempScop::print (invoked with opt -polly-scops -analyze) cannot print the AccFuncMap anymore as it would with a separate TempScop.

Differential Revision: http://reviews.llvm.org/D12803

llvm-svn: 247480
2015-09-11 21:41:48 +00:00
Michael Kruse 84bf8a3bc4 Introspect llvm-config --assertion-mode in cmake out-of-tree builds
When compiling Polly without LLVM sources but with system-installed
LLVM, the build process would not honor the LLVM_ENABLE_ASSERTIONS
setting LLVM was compiled with, but effectively assume that it is
switched off when compiling. During unit-tests llvm-lit would still
query the LLVM_ENABLE_ASSERTIONS flag and enable tests which require
assertions. Even if enabled for LLVM, Polly does not output its debug
info and statistics in this this mode such that 7 tests fail.

To fix, we query llvm-config --assertion-mode and if on, enable
assertions as HandleLLVMOptions.cmake would do.

We cannot reliably use HandleLLVMOptions.cmake itself as the host's
LLVM build might have been built using automake and distributions
change file locations (e.g. Debian to
/usr/share/llvm-${VERSION}/cmake/HandleLLVMOptions.cmake).

llvm-svn: 247470
2015-09-11 20:47:14 +00:00
Tobias Grosser 98cf5696fa Fix some typos in comments
llvm-svn: 247441
2015-09-11 18:26:59 +00:00
Sylvestre Ledru 3e94031632 Update autoconf too: Analysis/TempScopInfo.cpp has been removed
llvm-svn: 247419
2015-09-11 15:05:29 +00:00
Michael Kruse 07d5df4db8 Fix out-of-range access in test case
The function use_after_scop would iterate from 0 to 1024 and accessing element A[1024] where A has only valid indexes from 0 to 1023. Polly detects the situation of unconditionally undefined behavior and bail out in ScopInfo as non-feasible for optimization.

Other tests add impossible context assumptions as well, hance might show the same problem.

llvm-svn: 247412
2015-09-11 13:45:05 +00:00
Michael Kruse ef3cf01d1c Add Polly header files to IDE projects
llvm-svn: 247398
2015-09-11 09:01:55 +00:00
David Blaikie 0afc1e4ecc Update polly for explicit type parameter to global alias change
llvm-svn: 247382
2015-09-11 03:42:32 +00:00
Tobias Grosser 34b11fc197 XFAIL tests that require an additional LLVM patch to work
llvm-svn: 247338
2015-09-10 21:32:29 +00:00
Johannes Doerfert 90db75ed24 Runtime error check elimination
Hoist runtime checks in the loop nest if they guard an "error" like event.
  Such events are recognized as blocks with an unreachable terminator or a call
  to the ubsan function that deals with out of bound accesses. Other "error"
  events can be added easily.

  We will ignore these blocks when we detect/model/optmize and code generate SCoPs
  but we will make sure that they would not have been executed using the assumption
  framework.

llvm-svn: 247310
2015-09-10 17:51:27 +00:00
Johannes Doerfert f4fa9879fb [FIX] Do not assume only one loop can be left at a time
llvm-svn: 247291
2015-09-10 15:53:59 +00:00
Johannes Doerfert b68cffb5df Allow general loops with one latch
As we do not rely on ScalarEvolution any more we do not need to get
  the backedge taken count. Additionally, our domain generation handles
  everything that is affine and has one latch and our ScopDetection will
  over-approximate everything else.

  This change will therefor allow loops with:
    - one latch
    - exiting conditions that are affine

  Additionally, it will not check for structured control flow anymore.
  Hence, loops and conditionals are not necessarily single entry single
  exit regions any more.

Differential Version: http://reviews.llvm.org/D12758

llvm-svn: 247289
2015-09-10 15:27:46 +00:00
Michael Kruse d868b5d509 Merge TempScopInfo into ScopInfo
The TempScopInfo (-polly-analyze-ir) pass is removed and its work taken
over by ScopInfo (-polly-scops). Several tests depend on
-polly-analyze-ir and use -polly-scops instead which for the moment
prints the output of both passes. This again is not expected by some
other tests, especially those with negative searches, which have been
adapted.

Differential Version: http://reviews.llvm.org/D12694

llvm-svn: 247288
2015-09-10 15:25:24 +00:00
Michael Kruse 9cc1b9d31e Clean-up unit tests
Remove redundant flags and duplicate invocations of the same test.

llvm-svn: 247285
2015-09-10 14:42:09 +00:00
Johannes Doerfert 32ae76e7f9 [NFC] Remove obsolete arguments
Remove some arguments that survived the recent changes but are not
  used any more.

llvm-svn: 247280
2015-09-10 13:12:02 +00:00
Johannes Doerfert 5b9ff8b667 Replace ScalarEvolution based domain generation
This patch replaces the last legacy part of the domain generation, namely the
ScalarEvolution part that was used to obtain loop bounds. We now iterate over
the loops in the region and propagate the back edge condition to the header
blocks. Afterwards we propagate the new information once through the whole
region. In this process we simply ignore unbounded parts of the domain and
thereby assume the absence of infinite loops.

  + This patch already identified a couple of broken unit tests we had for
    years.
  + We allow more loops already and the step to multiple exit and multiple back
    edges is minimal.
  + It allows to model the overflow checks properly as we actually visit
    every block in the SCoP and know where which condition is evaluated.
  - It is currently not compatible with modulo constraints in the
    domain.

Differential Revision: http://reviews.llvm.org/D12499

llvm-svn: 247279
2015-09-10 13:00:06 +00:00
Johannes Doerfert 171f07ed71 Disable support for modulo expressions
The support for modulo expressions is not comlete and makes the new
  domain generation harder. As the currently broken domain generation
  needs to be replaced, we will first swap in the new, fixed domain
  generation and make it compatible with the modulo expressions later.

llvm-svn: 247278
2015-09-10 12:56:46 +00:00
Michael Kruse 7bf3944d23 Merge TempScopInfo.{cpp|h} into ScopInfo.{cpp|h}
This prepares for a series of patches that merges TempScopInfo into ScopInfo to
reduce Polly's code complexity. Only ScopInfo.{cpp|h} will be left thereafter.
Moving the code of TempScopInfo in one commit makes the mains diffs simpler to
understand.

In detail, merging the following classes is planned:
TempScopInfo into ScopInfo
TempScop into Scop
IRAccess into MemoryAccess

Only moving code, no functional changes intended.

Differential Version: http://reviews.llvm.org/D12693

llvm-svn: 247274
2015-09-10 12:46:52 +00:00
Chandler Carruth 66ef16b289 [PM] Update Polly for the new AA infrastructure landed in r247167.
llvm-svn: 247198
2015-09-09 22:13:56 +00:00
Michael Kruse d16550de92 Fix typo: zycle -> cycle [NFC]
llvm-svn: 247172
2015-09-09 18:20:31 +00:00
Johannes Doerfert 7ca8dc2d2d Disable support for pointer expressions
The support for pointer expressions is broken as it can only handle
  some patterns in the IslExprBuilder. We should to treat pointers in
  expressions the same as integers at some point and revert this patch.

llvm-svn: 247147
2015-09-09 14:19:04 +00:00
Michael Kruse da943ce613 Generate gitversion.h in autoconf builds
Add a custom makefile rule to generate lib/External/isl/gitversion.h
from GIT_HEAD_ID and trigger it using BULIT_SOURCES to ensure the file
exists before compilation starts.

The latest ISL creates gitversion.h from Makefile.am only, instead also
from configure.ac in previous version. While the Polly build invokes
configure, it does not invoke ISL's make such that the file was missing.

Invoking ISL's make would come with additional problems such as
triggering automake because of not preserved file time stamps.
Re-running automake might not be successful on other system
configurations for instance because it was preconfigured without
--with-clang option.

llvm-svn: 247142
2015-09-09 13:15:11 +00:00
Tobias Grosser f1ac57c6cd IslNodeBuilder: Add virtual function to obtain the schedule of an ast node
Not all users of our IslNodeBuilder will attach scheduling information to the
AST in the same way IslAstInfo is doing it today. By going through a virtual
function when extracting the schedule of an AST node other users can provide
their own functions for extract scheduling information in case they attach
scheduling information in a different way to the AST nodes.

No functional change for Polly itself intended.

llvm-svn: 247126
2015-09-09 09:24:38 +00:00
Johannes Doerfert 717b866798 Allow PHI nodes in the region exit block
While we do not need to model PHI nodes in the region exit (as it is not part
  of the SCoP), we need to prepare for the case that the exit block is split in
  code generation to create a single exiting block. If this will happen, hence
  if the region did not have a single exiting block before, we will model the
  operands of the PHI nodes as escaping scalars in the SCoP.

Differential Revision: http://reviews.llvm.org/D12051

llvm-svn: 247078
2015-09-08 21:44:27 +00:00
Tobias Grosser 02e6589bda Move more compile-time bailouts into -polly-detect-unprofitable
Instead of having two separate options
-polly-detect-scops-in-functions-without-loops and
-polly-detect-scops-in-regions-without-loops we now just use
-polly-detect-unprofitable to force the detection of scops ignoring any compile
time saving bailout heuristics.

llvm-svn: 247057
2015-09-08 19:46:41 +00:00
Tobias Grosser b8f3690e15 Add first run-time bounds elimination test case
llvm-svn: 247020
2015-09-08 16:02:19 +00:00
Tobias Grosser a89dc57b41 Do not use '.' in subfunction names
Certain backends, e.g. NVPTX, do not support '.' in function names. Hence,
we ensure all '.' are replaced by '_' when generating function names for
subfunctions. For the current OpenMP code generation, this is not strictly
necessary, but future uses cases (e.g. GPU offloading) need this issue to be
fixed.

llvm-svn: 246980
2015-09-08 06:22:17 +00:00
Tobias Grosser 12e650d682 Drop alias metadata in checks of RuntimeDebugBuilder test
Our alias metadata is currently not emitted in a deterministic order. As it
is not needed in this test, we just drop it for now (but keep in mind to fix
this).

llvm-svn: 246942
2015-09-06 08:59:50 +00:00
Tobias Grosser 86bc93a9b2 Add option -polly-codegen-add-debug-printing
When this option is enabled, Polly will emit printf calls for each scalar
load/and store which dump the scalar value loaded/stored at run time.

This patch also refactors the RuntimeDebugBuilder to use variadic templates
when generating CPU printfs. As result, it now becomes easier to print
strings that consist of a set of arguments. Also, as a single printf
call is emitted, it is more likely for such strings to be emitted atomically
if executed multi-threaded.

llvm-svn: 246941
2015-09-06 08:47:57 +00:00
Tobias Grosser e58d358171 RuntimeDebugPrinter: Simplify code [NFC]
llvm-svn: 246940
2015-09-06 07:17:54 +00:00
Tobias Grosser e3d8c05c5f Add some more documentation and structure to the collection of subtree references
Some of the structures are renamed, subfunction introduced to clarify the
individual steps and comments are added describing their functionality.

llvm-svn: 246929
2015-09-05 15:45:25 +00:00