[all-commits] [llvm/llvm-project] 1b811f: [DA] Delinearization of fixed-size multi-dimension...

[Bardia Mahjour via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 1b811ff8a935fafb279ad9bad36d36058a129b42
      https://github.com/llvm/llvm-project/commit/1b811ff8a935fafb279ad9bad36d36058a129b42
  Author: Bardia Mahjour <bmahjour at ca.ibm.com>
  Date:   2020-02-27 (Thu, 27 Feb 2020)

  Changed paths:
    M llvm/include/llvm/Analysis/DependenceAnalysis.h
    M llvm/lib/Analysis/DependenceAnalysis.cpp
    A llvm/test/Analysis/DependenceAnalysis/PreliminaryNoValidityCheckFixedSize.ll
    A llvm/test/Analysis/DependenceAnalysis/SimpleSIVNoValidityCheckFixedSize.ll
    M llvm/test/Transforms/LoopInterchange/currentLimitation.ll
    M llvm/test/Transforms/LoopInterchange/loop-interchange-optimization-remarks.ll
    M llvm/test/Transforms/LoopInterchange/profitability.ll

  Log Message:
  -----------
  [DA] Delinearization of fixed-size multi-dimensional arrays

Summary:
Currently the dependence analysis in LLVM is unable to compute accurate
dependence vectors for multi-dimensional fixed size arrays.
This is mainly because the delinearization algorithm in scalar evolution
relies on parametric terms to be present in the access functions. In the
case of fixed size arrays such parametric terms are not present, but we
can use the indexes from GEP instructions to recover the subscripts for
each dimension of the arrays. This patch adds this ability under the
existing option `-da-disable-delinearization-checks`.

Authored By: bmahjour

Reviewer: Meinersbur, sebpop, fhahn, dmgreen, grosser, etiotto, bollu

Reviewed By: Meinersbur

Subscribers: hiraditya, arphaman, Whitney, ppc-slack, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72178