llvm/lib/Transforms/Vectorize
Silviu Baranga e942cf87e8 [SCEV][LAA] Re-commit r260085 and r260086, this time with a fix for the memory
sanitizer issue. The PredicatedScalarEvolution's copy constructor
wasn't copying the Generation value, and was leaving it un-initialized.

Original commit message:

[SCEV][LAA] Add no wrap SCEV predicates and use use them to improve strided pointer detection

Summary:
This change adds no wrap SCEV predicates with:
  - support for runtime checking
  - support for expression rewriting:
      (sext ({x,+,y}) -> {sext(x),+,sext(y)}
      (zext ({x,+,y}) -> {zext(x),+,sext(y)}

Note that we are sign extending the increment of the SCEV, even for
the zext case. This is needed to cover the fairly common case where y would
be a (small) negative integer. In order to do this, this change adds two new
flags: nusw and nssw that are applicable to AddRecExprs and permit the
transformations above.

We also change isStridedPtr in LAA to be able to make use of
these predicates. With this feature we should now always be able to
work around overflow issues in the dependence analysis.

Reviewers: mzolotukhin, sanjoy, anemet

Subscribers: mzolotukhin, sanjoy, llvm-commits, rengolin, jmolloy, hfinkel

Differential Revision: http://reviews.llvm.org/D15412



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260112 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-08 17:02:45 +00:00
..
BBVectorize.cpp Vectorize: Remove implicit ilist iterator conversions, NFC 2015-10-19 22:06:09 +00:00
CMakeLists.txt
LLVMBuild.txt
LoopVectorize.cpp [SCEV][LAA] Re-commit r260085 and r260086, this time with a fix for the memory 2016-02-08 17:02:45 +00:00
SLPVectorizer.cpp [SLP] Fix placement of debug statement (NFC) 2016-02-08 14:11:39 +00:00
Vectorize.cpp [PM] Remove the old 'PassManager.h' header file at the top level of 2015-02-13 10:01:29 +00:00