Commit Graph

14 Commits

Author SHA1 Message Date
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
Johannes Doerfert 96425c2574 Traverse the SCoP to compute non-loop-carried domain conditions
In order to compute domain conditions for conditionals we will now
  traverse the region in the ScopInfo once and build the domains for
  each block in the region. The SCoP statements can then use these
  constraints when they build their domain.

  The reason behind this change is twofold:
    1) This removes a big chunk of preprocessing logic from the
       TempScopInfo, namely the Conditionals we used to build there.
       Additionally to moving this logic it is also simplified. Instead
       of walking the dominance tree up for each basic block in the
       region (as we did before), we now traverse the region only
       once in order to collect the domain conditions.
    2) This is the first step towards the isl based domain creation.
       The second step will traverse the region similar to this step,
       however it will propagate back edge conditions. Once both are in
       place this conditional handling will allow multiple exit loops
       additional logic.

Reviewers: grosser

Differential Revision: http://reviews.llvm.org/D12428

llvm-svn: 246398
2015-08-30 21:13:53 +00:00
Tobias Grosser 173ecab705 Remove target triples from test cases
I just learned that target triples prevent test cases to be run on other
architectures. Polly test cases are until now sufficiently target independent
to not require any target triples. Hence, we drop them.

llvm-svn: 235384
2015-04-21 14:28:02 +00:00
Tobias Grosser 5483931117 Rename 'scattering' to 'schedule'
In Polly we used both the term 'scattering' and the term 'schedule' to describe
the execution order of a statement without actually distinguishing between them.
We now uniformly use the term 'schedule' for the execution order.  This
corresponds to the terminology of isl.

History: CLooG introduced the term scattering as the generated code can be used
as a sequential execution order (schedule) or as a parallel dimension
enumerating different threads of execution (placement). In Polly and/or isl the
term placement was never used, but we uniformly refer to an execution order as a
schedule and only later introduce parallelism. When doing so we do not talk
about about specific placement dimensions.

llvm-svn: 235380
2015-04-21 11:37:25 +00:00
Tobias Grosser 619190d5a7 Delinearization of expressions that contain array size parameters
This allows us to delinerize code such as:

  A[][n]

  for (i
    for (j
      A[i][n-j-1] = ...

which would previously have been delinearize to an access A[i+1][-j-1].

To recover the correct access we apply the piecewise expression:

  { A[i][j] -> A[i-1][i+N]: i < 0; A[i][j] -> A[i][i]: i >= 0}

This approach generalizes to higher dimensions.

llvm-svn: 233566
2015-03-30 17:22:28 +00:00
David Blaikie bad3ff207f Update Polly tests to handle explicitly typed gep changes in LLVM
llvm-svn: 230784
2015-02-27 19:20:19 +00:00
Tobias Grosser d1e33e7061 ScopDetection: Only detect scops that have at least one read and one write
Scops that only read seem generally uninteresting and scops that only write are
most likely initializations where there is also little to optimize.  To not
waste compile time we bail early.

Differential Revision: http://reviews.llvm.org/D7735

llvm-svn: 229820
2015-02-19 05:31:07 +00:00
Johannes Doerfert 9282076ece [NFC] Drop the "scattering" tuple name
llvm-svn: 227801
2015-02-02 13:45:54 +00:00
Tobias Grosser 3f29619614 Drop all constant scheduling dimensions
Schedule dimensions that have the same constant value accross all statements do
not carry any information, but due to the increased dimensionality of the
schedule cost compile time. To not pay this cost, we remove constant dimensions
if possible.

llvm-svn: 225067
2015-01-01 23:01:11 +00:00
Tobias Grosser f57d63f906 Do allow negative offsets in the outermost array dimension
There is no needed for neither 1-dimensional nor higher dimensional arrays to
require positive offsets in the outermost array dimension.

We originally introduced this assumption with the support for delinearizing
multi-dimensional arrays.

llvm-svn: 214665
2014-08-03 21:07:30 +00:00
Tobias Grosser 5e6813d184 Derive run-time conditions for delinearization
As our delinearization works optimistically, we need in some cases run-time
checks that verify our optimistic assumptions. A simple example is the
following code:

void foo(long n, long m, long o, double A[n][m][o]) {

  for (long i = 0; i < 100; i++)
    for (long j = 0; j < 150; j++)
      for (long k = 0; k < 200; k++)
        A[i][j][k] = 1.0;
}

After clang linearized the access to A and we delinearized it again to
A[i][j][k] we need to ensure that we do not access the delinearized array
out of bounds (this information is not available in LLVM-IR). Hence, we
need to verify the following constraints at run-time:

CHECK:   Assumed Context:
CHECK:   [o, m] -> {  : m >= 150 and o >= 200 }
llvm-svn: 212198
2014-07-02 17:47:48 +00:00
Sebastian Pop 1801668af3 delinearize memory access functions
llvm-svn: 205799
2014-04-08 21:20:44 +00:00
Tobias Grosser 4f96749351 ScopInfo: Clarify may-write and must-write accesses
llvm-svn: 184658
2013-06-23 05:21:18 +00:00
Tobias Grosser 6a2da6b9c8 Add test cases for multi-dimensional variable lengths arrays
At the moment we can handle such arrays only by conservatively assuming that
each access to such an array may touch any element in the array. It would be
great if we could improve Polly/LLVM at some point, such that we can
recover the multi-dimensionality of the accesses.

llvm-svn: 163619
2012-09-11 14:03:19 +00:00