llvm-project/polly
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
..
autoconf Remove OpenScop 2014-04-11 09:47:45 +00:00
cmake Remove OpenScop 2014-04-11 09:47:45 +00:00
docs
include Derive run-time conditions for delinearization 2014-07-02 17:47:48 +00:00
lib Derive run-time conditions for delinearization 2014-07-02 17:47:48 +00:00
test Derive run-time conditions for delinearization 2014-07-02 17:47:48 +00:00
tools Update the copyright credits -- Happy new year 2014! 2014-01-01 08:27:31 +00:00
utils Remove use of llvm.codegen intrinsic for GPGPU codegen 2014-06-24 08:11:36 +00:00
www www: Fix grammar. 2014-06-10 20:18:16 +00:00
.gitattributes gitattributes: .png and .txt are no text files 2013-07-28 09:05:20 +00:00
CMakeLists.txt Reorder cmake include folders (polly source first) 2014-05-28 16:54:42 +00:00
CREDITS.txt Add "Yabin Hu" to CREDITS.txt 2014-06-21 18:35:33 +00:00
LICENSE.txt Update the copyright credits -- Happy new year 2014! 2014-01-01 08:27:31 +00:00
Makefile Revert "Fix a bug introduced by r153739: We are not able to provide the correct" 2012-04-11 07:43:13 +00:00
Makefile.common.in 'chmod -x' on files that do not need the executable bits 2012-12-29 15:09:03 +00:00
Makefile.config.in Remove OpenScop 2014-04-11 09:47:45 +00:00
README Trivial change to the README, mainly to test commit access. 2012-10-09 04:59:42 +00:00
configure Remove OpenScop 2014-04-11 09:47:45 +00:00

README

Polly - Polyhedral optimizations for LLVM
-----------------------------------------
http://polly.llvm.org/

Polly uses a mathematical representation, the polyhedral model, to represent and
transform loops and other control flow structures. Using an abstract
representation it is possible to reason about transformations in a more general
way and to use highly optimized linear programming libraries to figure out the
optimal loop structure. These transformations can be used to do constant
propagation through arrays, remove dead loop iterations, optimize loops for
cache locality, optimize arrays, apply advanced automatic parallelization, drive
vectorization, or they can be used to do software pipelining.