Commit Graph

4 Commits

Author SHA1 Message Date
Ayal Zaks d9bc43ef2a [LV] Fix PR33613 - retain order of insertelement per part
r306381 caused PR33613, by reversing the order in which insertelements were
generated per unroll part. This patch fixes PR33613 by retraining this order,
placing each set of insertelements per part immediately after the last scalar
being packed for this part. Includes a test case derived from PR33613.

Reference: https://bugs.llvm.org/show_bug.cgi?id=33613
Differential Revision: https://reviews.llvm.org/D34760

llvm-svn: 306575
2017-06-28 17:59:33 +00:00
Anna Thomas dcdb325fee [LV] Fix the vector code generation for first order recurrence
Summary:
In first order recurrences where phi's are used outside the loop,
we should generate an additional vector.extract of the second last element from
the vectorized phi update.
This is because we require the phi itself (which is the value at the second last
iteration of the vector loop) and not the phi's update within the loop.
Also fix the code gen when we just unroll, but don't vectorize.
Fixes PR32396.

Reviewers: mssimpso, mkuper, anemet

Subscribers: llvm-commits, mzolotukhin

Differential Revision: https://reviews.llvm.org/D31979

llvm-svn: 300238
2017-04-13 18:59:25 +00:00
Anna Thomas 00dc1b74b7 [LV] Avoid vectorizing first order recurrence when phi uses are outside loop
In the vectorization of first order recurrence, we vectorize such
that the last element in the vector will be the one extracted to pass into the
scalar remainder loop. However, this is not true when there is a phi (other
than the primary induction variable) is used outside the loop.
In such a case, we need the value from the second last iteration (i.e.
the phi value), not the last iteration (which would be the phi update).
I've added a test case for this. Also see PR32396.

A follow up patch would generate the correct code gen for such cases,
and turn this vectorization on.

Differential Revision: https://reviews.llvm.org/D31910

Reviewers: mssimpso
llvm-svn: 299985
2017-04-11 21:02:00 +00:00
Anna Thomas 98cbb067ce [LV] Move first order recurrence test to common folder. NFC
llvm-svn: 299969
2017-04-11 18:31:42 +00:00