3 Commits

Author SHA1 Message Date
Evgeny Stupachenko
9d35c64dc2 The patch fixes PR27392.
Summary:
 It is incorrect to compare TripCount (which is BECount + 1)
  with extraiters (or Count) to check if we should enter unrolled
  loop or not, because TripCount can potentially overflow
  (when BECount is max unsigned integer).
 While comparing BECount with (Count - 1) is overflow safe and
  therefore correct.

Reviewer: hfinkel

Differential Revision: http://reviews.llvm.org/D19256

From: Evgeny Stupachenko <evstupac@gmail.com>
llvm-svn: 267662
2016-04-27 03:04:54 +00:00
David L Kreitzer
01b0be98a9 Adds the ability to use an epilog remainder loop during loop unrolling and makes
this the default behavior.

Patch by Evgeny Stupachenko (evstupac@gmail.com).

Differential Revision: http://reviews.llvm.org/D18158

llvm-svn: 265388
2016-04-05 12:19:35 +00:00
Kevin Qin
fdbff51f47 [AArch64] Enable partial & runtime unrolling on cortex-a57
For inner one of nested loops, it is more likely to be a hot loop,
and the runtime check can be promoted out from patch 0001, so the
overhead is less, we can try a doubled threshold to unroll more loops.

llvm-svn: 231632
2015-03-09 06:14:28 +00:00