induction variable to be perfect
This patch allow more conditional branches to be considered as loop
guard, and so more loop nests can be considered perfect.
Reviewed By: bmahjour, sidbav
Differential Revision: https://reviews.llvm.org/D94717
Allow loop nests with empty basic blocks without loops in different
levels as perfect.
Reviewers: Meinersbur
Differential Revision: https://reviews.llvm.org/D93665
Allow loop nests with empty basic blocks without loops in different
levels as perfect.
Reviewers: Meinersbur
Differential Revision: https://reviews.llvm.org/D93665
Summary: This patch adds an analysis pass to collect loop nests and
summarize properties of the nest (e.g the nest depth, whether the nest
is perfect, what's the innermost loop, etc...).
The motivation for this patch was discussed at the latest meeting of the
LLVM loop group (https://ibm.box.com/v/llvm-loop-nest-analysis) where we
discussed
the unimodular loop transformation framework ( “A Loop Transformation
Theory and an Algorithm to Maximize Parallelism”, Michael E. Wolf and
Monica S. Lam, IEEE TPDS, October 1991). The unimodular framework
provides a convenient way to unify legality checking and code generation
for several loop nest transformations (e.g. loop reversal, loop
interchange, loop skewing) and their compositions. Given that the
unimodular framework is applicable to perfect loop nests this is one
property of interest we expose in this analysis. Several other utility
functions are also provided. In the future other properties of interest
can be added in a centralized place.
Authored By: etiotto
Reviewer: Meinersbur, bmahjour, kbarton, Whitney, dmgreen, fhahn,
reames, hfinkel, jdoerfert, ppc-slack
Reviewed By: Meinersbur
Subscribers: bryanpkc, ppc-slack, mgorny, hiraditya, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D68789
Summary: This patch adds an analysis pass to collect loop nests and
summarize properties of the nest (e.g the nest depth, whether the nest
is perfect, what's the innermost loop, etc...).
The motivation for this patch was discussed at the latest meeting of the
LLVM loop group (https://ibm.box.com/v/llvm-loop-nest-analysis) where we
discussed
the unimodular loop transformation framework ( “A Loop Transformation
Theory and an Algorithm to Maximize Parallelism”, Michael E. Wolf and
Monica S. Lam, IEEE TPDS, October 1991). The unimodular framework
provides a convenient way to unify legality checking and code generation
for several loop nest transformations (e.g. loop reversal, loop
interchange, loop skewing) and their compositions. Given that the
unimodular framework is applicable to perfect loop nests this is one
property of interest we expose in this analysis. Several other utility
functions are also provided. In the future other properties of interest
can be added in a centralized place.
Authored By: etiotto
Reviewer: Meinersbur, bmahjour, kbarton, Whitney, dmgreen, fhahn,
reames, hfinkel, jdoerfert, ppc-slack
Reviewed By: Meinersbur
Subscribers: bryanpkc, ppc-slack, mgorny, hiraditya, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D68789
Whitney Tsang