The dpbusd_const.ll test change is due to us losing the expanded add reduction pattern as one of the elements is known to be zero (removing one of the adds from the reduction pyramid). I don't think its of concern.
Noticed while working on #107423
PowerPC subtargets prior to Power9 use the 'legacy' itinerary way to
provide scheduling information. This patch re-writes the tablegen file
to define the scheduling information in the new SchedModel way, which
can bring improvements to some benchmarks.
Reviewed By: shchenz
Differential Revision: https://reviews.llvm.org/D154488
The LIT test cases were migrated with the script provided by
Nikita Popov. Due to the size of the change it is split into
several parts.
Reviewed By: nemanja, nikic
Differential Revision: https://reviews.llvm.org/D135474
We are going to remove the old 'perfect shuffle' optimization since it
brings performance penalty in hot loop around vectors. For example, in
following loop sharing the same mask:
%v.1 = shufflevector ... <0,1,2,3,8,9,10,11,16,17,18,19,24,25,26,27>
%v.2 = shufflevector ... <0,1,2,3,8,9,10,11,16,17,18,19,24,25,26,27>
The generated instructions will be `vmrglw-vmrghw-vmrglw-vmrghw` instead
of `vperm-vperm`. In some large loop cases, this causes 20%+ performance
penalty.
The original attempt to resolve this is to pre-record masks of every
shufflevector operation in DAG, but that is somewhat complex and brings
unnecessary computation (to scan all nodes) in optimization. Here we
disable it by default. There're indeed some cases becoming worse after
this, which will be fixed in a more careful way in future patches.
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D121082
Some of the pattern matching in PPCInstrVSX.td and node lowering involving vectors assumes 64bit mode. This patch disables some of the unsafe pattern matching and lowering of BUILD_VECTOR in 32bit mode.
Reviewed By: Xiangling_L
Differential Revision: https://reviews.llvm.org/D92789
