Commit Graph

5 Commits

Author SHA1 Message Date
Sam Parker 1c3ca61294 [ARM][ParallelDSP] Change smlad insertion order
Instead of inserting everything after the 'root' of the reduction,
insert all instructions as close to their operands as possible. This
can help reduce register pressure.

Differential Revision: https://reviews.llvm.org/D67392

llvm-svn: 374981
2019-10-16 09:37:03 +00:00
Sam Parker fea532230b [ARM][ParallelDSP] SExt mul for accumulation
For any unpaired muls, we accumulate them as an input to the
reduction. Check the type of the mul and perform a sext if the
existing accumlator input type is not the same.

Differential Revision: https://reviews.llvm.org/D66993

llvm-svn: 370851
2019-09-04 08:41:34 +00:00
Sam Parker a761ba0f2d [ARM][ParallelDSP] Change search for muls
rL369567 reverted a couple of recent changes made to ARMParallelDSP
because of a miscompilation error: PR43073.

The issue stemmed from an underlying bug that was caused by adding
muls into a reduction before it was proved that they could be executed
in parallel with another mul.

Most of the changes here are from the previously reverted commits.
The additional changes have been made area:
1) The Search function now doesn't insert any muls into the Reduction
   object. That now happens once the search has successfully finished.
2) For any muls added into the reduction but that weren't paired, we
   accumulate their values as an input into the smlad.

Differential Revision: https://reviews.llvm.org/D66660

llvm-svn: 370171
2019-08-28 08:51:13 +00:00
Nico Weber ed18e70c86 Revert r367389 (and follow-up r368404); it caused PR43073.
llvm-svn: 369567
2019-08-21 19:53:42 +00:00
Sam Parker 0dba791a25 [ARM][ParallelDSP] Replace SExt uses
As loads are combined and widened, we replaced their sext users
operands whereas we should have been replacing the uses of the sext.
I've added a load of tests, with only a few of them originally
causing assertion failures, the rest improve pattern coverage.

Differential Revision: https://reviews.llvm.org/D65740

llvm-svn: 368404
2019-08-09 07:48:50 +00:00