Commit Graph

770 Commits

Author SHA1 Message Date
Tobias Grosser 0865e775bf ScopInfo: Remove indentation in hoistInvariantLoads
We move verifyInvariantLoads out of this function to allow for an early return
without the need for code duplication. A similar transformation was suggested
by Johannes Doerfert in post commit review of r262033.

llvm-svn: 262203
2016-02-29 07:29:42 +00:00
Tobias Grosser 4fb9e51664 ScopInfo: Drop some debug statements
This debug output distracts from the -debug-only=polly-scops output. As it is
rather verbose and only really needed for debugging the domain construction
I drop this output. The domain construction is meanwhile stable enough to
not require regular debugging.

llvm-svn: 262117
2016-02-27 06:59:30 +00:00
Hongbin Zheng 8efb22ef25 Enable llvm's isa/cast/dyn_cast on MemAccInst.
Differential Revision: http://reviews.llvm.org/D17250

llvm-svn: 262100
2016-02-27 01:49:58 +00:00
Hongbin Zheng 9691d71674 Introduce fine-grain dependence analysis by tagging access functions and schedules tree with either the id of memory access or memory references.
Differential Revision: http://reviews.llvm.org/D17381

llvm-svn: 262039
2016-02-26 17:05:24 +00:00
Tobias Grosser 8fa3e4c3fb ScopDetect/Info: Add option to disable invariant load hoisting
This is helpful for test case reduction and other experiments.

llvm-svn: 262033
2016-02-26 16:43:35 +00:00
Michael Kruse 0ac2d3e217 ScopDetection: Fix mix-up of isLoad and isStore.
This was accidentally introduced in r258947.

Thanks to Hongbin Zheng for finding this.

Found-by: etherzhhb
llvm-svn: 262032
2016-02-26 16:40:35 +00:00
Michael Kruse 37d136e48e Reduce indention. NFC.
The functions buildAccessMultiDimFixed and buildAccessMultiDimParam were
refactored from buildMemoryAccess. In their own functions, the control
flow can be shortcut and simplified using returns.

Suggested-by: etherzhhb
llvm-svn: 262029
2016-02-26 16:08:24 +00:00
Hongbin Zheng f3d6612c0a [MemAccInst] Introduce the '->' operator and remove the simple wrapper functions. NFC
llvm-svn: 261994
2016-02-26 09:47:11 +00:00
Hongbin Zheng f43e9925ee Coalesce Read/Write/MayWrite right after we collected them. NFC
llvm-svn: 261993
2016-02-26 09:47:08 +00:00
Chandler Carruth 7553e95098 Fix a warning about an unused variable in release builds.
llvm-svn: 261956
2016-02-26 02:25:06 +00:00
Johannes Doerfert a792098047 Support calls with known ModRef function behaviour
Check the ModRefBehaviour of functions in order to decide whether or
  not a call instruction might be acceptable.

Differential Revision: http://reviews.llvm.org/D5227

llvm-svn: 261866
2016-02-25 14:08:48 +00:00
Johannes Doerfert 8c83078449 Simplify code [NFC]
llvm-svn: 261864
2016-02-25 14:07:49 +00:00
Johannes Doerfert 9dd42ee7c1 Try to build alias checks even when non-affine accesses are allowed
From now on we bail only if a non-trivial alias group contains a non-affine
  access, not when we discover aliasing and non-affine accesses are allowed.

llvm-svn: 261863
2016-02-25 14:06:11 +00:00
Michael Kruse 7b5caa4a72 Introduce ScopStmt::getRegionNode(). NFC.
Replace an inline ternary operator pattern.

llvm-svn: 261793
2016-02-24 22:08:28 +00:00
Michael Kruse 375cb5fe0a Introduce ScopStmt::getEntryBlock(). NFC.
This replaces an ungly inline ternary operator pattern.

llvm-svn: 261792
2016-02-24 22:08:24 +00:00
Michael Kruse 6f7721f02b Introduce Scop::getStmtFor. NFC.
Replace Scop::getStmtForBasicBlock and Scop::getStmtForRegionNode, and
add overloads for llvm::Instruction and llvm::RegionNode.

getStmtFor and overloads become the common interface to get the Stmt
that contains something. Named after LoopInfo::getLoopFor and
RegionInfo::getRegionFor.

llvm-svn: 261791
2016-02-24 22:08:19 +00:00
Michael Kruse 526fcf5f0d Use inline variable declaration. NFC.
llvm-svn: 261788
2016-02-24 22:08:08 +00:00
Johannes Doerfert cea6193b79 Support memory intrinsics
This patch adds support for memcpy, memset and memmove intrinsics. They are
  represented as one (memset) or two (memcpy, memmove) memory accesses in the
  polyhedral model. These accesses have an access range that describes the
  summarized effect of the intrinsic, i.e.,
    memset(&A[i], '$', N);
  is represented as a write access from A[i] to A[i+N].

Differential Revision: http://reviews.llvm.org/D5226

llvm-svn: 261489
2016-02-21 19:13:19 +00:00
Johannes Doerfert b92e218ca8 [Refactor] Add missing newline after functions
llvm-svn: 261478
2016-02-21 16:37:58 +00:00
Johannes Doerfert a90943d74b [Refactor] Indicate pointer and reference types when auto is used
See also:
    http://llvm.org/docs/CodingStandards.html#use-auto-type-deduction-to-make-code-more-readable

llvm-svn: 261477
2016-02-21 16:37:25 +00:00
Johannes Doerfert 68898ce3b5 [Refactor] Avoid variables with name of types
llvm-svn: 261475
2016-02-21 16:36:21 +00:00
Hongbin Zheng ff4b63739e Introduce helper function to build isl_flow, NFC.
llvm-svn: 261436
2016-02-20 14:45:48 +00:00
Hongbin Zheng 403853f20b Add the missing modifier 'static' for addZeroPaddingToSchedule, NFC
llvm-svn: 261435
2016-02-20 14:45:46 +00:00
Hongbin Zheng 86f43eab8b Assign meaningful name to MemoryAccess. NFC
Now the name of MemoryAccess is <StatementName>_[Read|Write|MayWrite]<Number>_<BaseName>,
e.g. Stmt_for_body_4_Read0_MemRef_A

llvm-svn: 261401
2016-02-20 03:40:15 +00:00
Johannes Doerfert 4d9bb8d594 Allow all combinations of types and subscripts for memory accesses
To support non-aligned accesses we introduce a virtual element size
  for arrays that divides each access function used for this array. The
  adjustment of the access function based on the element size of the
  array was therefore moved after this virtual element size was
  determined, thus after all accesses have been created.

Differential Revision: http://reviews.llvm.org/D17246

llvm-svn: 261226
2016-02-18 16:50:12 +00:00
Hongbin Zheng 8831eb7db4 [Refactor] Move isl_ctx into Scop.
After we moved isl_ctx into Scop, we need to free the isl_ctx after
  freeing all isl objects, which requires the ScopInfo pass to be freed
  at last. But this is not guaranteed by the PassManager, and we need
  extra code to free the isl_ctx at the right time.

  We introduced a shared pointer to manage the isl_ctx, and distribute
  it to all analyses that create isl objects. As such, whenever we free
  an analyses with the shared_ptr (and also free the isl objects which
  are created by the analyses), we decrease the (shared) reference
  counter of the shared_ptr by 1. Whenever the reference counter reach
  0 in the releaseMemory function of an analysis, that analysis will
  be the last one that hold any isl objects, and we can safely free the
  isl_ctx with that analysis.

Differential Revision: http://reviews.llvm.org/D17241

llvm-svn: 261100
2016-02-17 15:49:21 +00:00
Tobias Grosser a2ee003239 ScopDectect: Allow memory accesses with different element types by default (try 3)
First support for this feature was committed in r259784. Support for
loop invariant load hoisting with different types was added by
Johannes Doerfert in r260045 and r260886.

llvm-svn: 260965
2016-02-16 14:37:24 +00:00
Johannes Doerfert 4cf1580f0c [FIX] Check the next base pointer for possible invariant loads
A load can only be invariant if its base pointer is invariant too. To
  this end, we check if the base pointer is defined inside the region or
  outside. In the former case we recursively check if we can (and
  therefore will) hoist the base pointer too. Only if that happends we
  can hoist the load.

llvm-svn: 260886
2016-02-15 12:42:05 +00:00
Johannes Doerfert f69162486b Revert "[FIX] Hoist accesses if AA stated they are invariant"
This reverts commit 98efa006c96ac981c00d2e386ec1102bce9f549a.

  The fix was broken since we do not use AA in the ScopDetection anymore to
  check for invariant accesses.

llvm-svn: 260884
2016-02-15 12:21:11 +00:00
Hongbin Zheng 226232044a [Refactor] Eliminate the global variable "InsnToMemAcc".
Eliminate the global variable "InsnToMemAcc" to make Scop/ScopInfo become
  more protable, such that we can safely use them in a CallGraphSCC pass.

Differential Revision: http://reviews.llvm.org/D17238

llvm-svn: 260863
2016-02-15 00:20:58 +00:00
Johannes Doerfert 2353e39e1f [FIX] Hoist accesses if AA stated they are invariant
Before this patch it could happen that we did not hoist a load that
  was a base pointer of another load even though AA already declared the
  first one as invariant (during ScopDetection). If this case arises we
  will now skipt the "can be overwriten" check because in this case the
  over-approximating nature causes us to generate broken code.

llvm-svn: 260862
2016-02-14 23:37:14 +00:00
Johannes Doerfert 3ff2221cfc Split ScopArrayInfo::updateSizes into two functions
The former ScopArrayInfo::updateSizes was implicitly divided into an
  updateElementType and an updateSizes. Now this partitioning is
  explicit.

llvm-svn: 260860
2016-02-14 22:31:39 +00:00
Tobias Grosser 5e27ec33ea Revert "[ScopDectect] Allow memory accesses with different element types by default"
This reverts commit https://llvm.org/svn/llvm-project/polly/trunk@260853

We unfortunately still have two bugs left which show only up with
-polly-process-unprofitable and which I forgot to test before committing.

llvm-svn: 260854
2016-02-14 19:59:29 +00:00
Tobias Grosser 5f105f9bdd [ScopDectect] Allow memory accesses with different element types by default
First support for this feature was committed in r259784. Support for
loop invariant load hoisting with different types was added by Johannes
Doerfert in r260045. This fixed the last known bug.

llvm-svn: 260853
2016-02-14 19:11:16 +00:00
Hongbin Zheng fec328083a Use unique_ptr to manage Scop inside ScopInfo.
llvm-svn: 260821
2016-02-13 15:13:02 +00:00
Hongbin Zheng 660f3ccfa5 Move AccFuncMap from ScopInfo into Scop
Since the origin AccFuncMap in ScopInfo is used by the underlying Scop
  only, and it must stay alive until we delete the Scop. It will be better
  if we simply move the origin AccFuncMap in ScopInfo into the Scop class.

llvm-svn: 260820
2016-02-13 15:12:58 +00:00
Hongbin Zheng 192f69a0fb Do not carry LoopInfo along with a Scop.
Make Scop become more portable such that we can use it in a CallGraphSCC pass.
  The first step is to drop the analyses that are only used during Scop construction.
  This patch drop LoopInfo from Scop.

llvm-svn: 260819
2016-02-13 15:12:54 +00:00
Hongbin Zheng f53ffa6dc3 Do not carry DominatorTree along with a Scop.
Make Scop become more portable such that we can use it in a CallGraphSCC pass.
  The first step is to drop the analyses that are only used during Scop construction.
  This patch drop DominatorTree from Scop.

llvm-svn: 260818
2016-02-13 15:12:51 +00:00
Hongbin Zheng 7dddfba7dc Do not carry ScopDetection along with a Scop.
Make Scop become more portable such that we can use it in a CallGraphSCC pass.
  The first step is to drop the analyses that are only used during Scop construction.
  This patch drop ScopDecection from Scop.

llvm-svn: 260817
2016-02-13 15:12:47 +00:00
Johannes Doerfert 96e5471139 Separate invariant equivalence classes by type
We now distinguish invariant loads to the same memory location if they
  have different types. This will cause us to pre-load an invariant
  location once for each type that is used to access it. However, we can
  thereby avoid invalid casting, especially if an array is accessed
  though different typed/sized invariant loads.

  This basically reverts the changes in r260023 but keeps the test
  cases.

llvm-svn: 260045
2016-02-07 17:30:13 +00:00
Johannes Doerfert e708790c59 [FIX] Two "off-by-one" error in constant range usage
llvm-svn: 260031
2016-02-07 13:59:03 +00:00
Johannes Doerfert adeab372ca Simplify code [NFC]
llvm-svn: 260030
2016-02-07 13:57:32 +00:00
Tobias Grosser 8ebdc2dd53 Make memory accesses with different element types optional
We also disable this feature by default, as there are still some issues in
combination with invariant load hoisting that slipped through my initial
testing.

llvm-svn: 260025
2016-02-07 08:48:57 +00:00
Tobias Grosser 46bafbd0fe Do not yet consider loads with non-canonical element size for load hoisting.
Invariant load hoisting of memory accesses with non-canonical element
types lacks support for equivalence classes that contain elements of
different width/size. This support should be added, but to get our buildbots
back to green, we disable load hoisting for memory accesses with non-canonical
element size for now.

llvm-svn: 260023
2016-02-07 08:11:36 +00:00
Michael Kruse 2e02d560aa Follow uses to create value MemoryAccesses
The previously implemented approach is to follow value definitions and
create write accesses ("push defs") while searching for uses. This
requires the same relatively validity- and requirement conditions to be
replicated at multiple locations (PHI instructions, other instructions,
uses by PHIs).

We replace this by iterating over the uses in a SCoP ("pull in
requirements"), and add writes only when at least one read has been
added. It turns out to be simpler code because each use is only iterated
over once and writes are added for the first access that reads it. We
need another iteration to identify escaping values (uses not in the
SCoP), which also makes the difference between such accesses more
obvious. As a side-effect, the order of scalar MemoryAccess can change.

Differential Revision: http://reviews.llvm.org/D15706

llvm-svn: 259987
2016-02-06 09:19:40 +00:00
Tobias Grosser d840fc7277 Support accesses with differently sized types to the same array
This allows code such as:

void multiple_types(char *Short, char *Float, char *Double) {
  for (long i = 0; i < 100; i++) {
    Short[i] = *(short *)&Short[2 * i];
    Float[i] = *(float *)&Float[4 * i];
    Double[i] = *(double *)&Double[8 * i];
  }
}

To model such code we use as canonical element type of the modeled array the
smallest element type of all original array accesses, if type allocation sizes
are multiples of each other. Otherwise, we use a newly created iN type, where N
is the gcd of the allocation size of the types used in the accesses to this
array. Accesses with types larger as the canonical element type are modeled as
multiple accesses with the smaller type.

For example the second load access is modeled as:

  { Stmt_bb2[i0] -> MemRef_Float[o0] : 4i0 <= o0 <= 3 + 4i0 }

To support code-generating these memory accesses, we introduce a new method
getAccessAddressFunction that assigns each statement instance a single memory
location, the address we load from/store to. Currently we obtain this address by
taking the lexmin of the access function. We may consider keeping track of the
memory location more explicitly in the future.

We currently do _not_ handle multi-dimensional arrays and also keep the
restriction of not supporting accesses where the offset expression is not a
multiple of the access element type size. This patch adds tests that ensure
we correctly invalidate a scop in case these accesses are found. Both types of
accesses can be handled using the very same model, but are left to be added in
the future.

We also move the initialization of the scop-context into the constructor to
ensure it is already available when invalidating the scop.

Finally, we add this as a new item to the 2.9 release notes

Reviewers: jdoerfert, Meinersbur

Differential Revision: http://reviews.llvm.org/D16878

llvm-svn: 259784
2016-02-04 13:18:42 +00:00
Tobias Grosser e2c31210b2 Revert "Support loads with differently sized types from a single array"
This reverts commit (@259587). It needs some further discussions.

llvm-svn: 259629
2016-02-03 05:53:27 +00:00
Tobias Grosser 5d3fc1ea43 Support loads with differently sized types from a single array
We support now code such as:

void multiple_types(char *Short, char *Float, char *Double) {
  for (long i = 0; i < 100; i++) {
    Short[i] = *(short *)&Short[2 * i];
    Float[i] = *(float *)&Float[4 * i];
    Double[i] = *(double *)&Double[8 * i];
  }
}

To support such code we use as element type of the modeled array the smallest
element type of all original array accesses. Accesses with larger types are
modeled as multiple accesses with the smaller type.

For example the second load access is modeled as:

  { Stmt_bb2[i0] -> MemRef_Float[o0] : 4i0 <= o0 <= 3 + 4i0 }

To support jscop-rewritable memory accesses we need each statement instance to
only be assigned a single memory location, which will be the address at which
we load the value. Currently we obtain this address by taking the lexmin of
the access function. We may consider keeping track of the memory location more
explicitly in the future.

llvm-svn: 259587
2016-02-02 22:05:29 +00:00
Tobias Grosser db543ede7e ScopInfo: Split memory access construction into different cases
We create separate functions for fixed-size multi-dimensional, parameteric-sized
multi-dimensional, as well as single-dimensional memory accesses to reduce the
complexity of a large monolithic function.

Suggested-by: Michael Kruse <llvm@meinersbur.de>
llvm-svn: 259522
2016-02-02 16:46:49 +00:00
Tobias Grosser 5d51afedd8 ScopInfo: Do not track element-size as additional array size dimension [NFC]
There is no need to pass the size of the elements as the last size dimension
to ScopArrayInfo. This information is already available through the ElementType.
Tracking it twice is not only redundant but may result in inconsistencies.

llvm-svn: 259521
2016-02-02 16:46:45 +00:00