hanchenye-llvm-project/polly
Michael Kruse ee6a4fc680 Unique phi write accesses
Ensure that there is at most one phi write access per PHINode and
ScopStmt. In particular, this would be possible for non-affine
subregions with multiple exiting blocks. We replace multiple MAY_WRITE
accesses by one MUST_WRITE access. The written value is constructed
using a PHINode of all exiting blocks. The interpretation of the PHI
WRITE's "accessed value" changed from the incoming value to the PHI like
for PHI READs since there is no unique incoming value.

Because region simplification shuffles around PHI nodes -- particularly
with exit node PHIs -- the PHINodes at analysis time does not always
exist anymore in the code generation pass. We instead remember the
incoming block/value pair in the MemoryAccess.

Differential Revision: http://reviews.llvm.org/D15681

llvm-svn: 258809
2016-01-26 13:33:27 +00:00
..
autoconf Generate gitversion.h in autoconf builds 2015-09-09 13:15:11 +00:00
cmake Compile ISL into its own library 2015-09-24 11:30:22 +00:00
include/polly Unique phi write accesses 2016-01-26 13:33:27 +00:00
lib Unique phi write accesses 2016-01-26 13:33:27 +00:00
test Unique phi write accesses 2016-01-26 13:33:27 +00:00
tools Do not compile GPU library with sanitizers 2015-07-28 12:51:23 +00:00
utils Revise polly-{update|check}-format targets 2015-09-14 16:59:50 +00:00
www www: Update links to LLVM bug tracker 2016-01-22 08:19:54 +00:00
.arcconfig Adjusted arc linter config for modern version of arcanist 2015-08-12 09:01:16 +00:00
.arclint Adjusted arc linter config for modern version of arcanist 2015-08-12 09:01:16 +00:00
.gitattributes
.gitignore Add git patch files to .gitignore 2015-06-23 20:55:01 +00:00
CMakeLists.txt Add -sort-includes to our automatic source code formatting 2015-10-15 12:18:37 +00:00
CREDITS.txt Add myself to the credits 2014-08-10 03:37:29 +00:00
LICENSE.txt
Makefile
Makefile.common.in
Makefile.config.in Fix autotools build 2015-06-25 16:50:13 +00:00
README
configure Enable ISL's small integer optimization 2015-06-25 20:47:35 +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.