Fixes PR30730.
This is a re-commit of a pulled commit. The commit was pulled because some
software projects contained uses of Altivec vectors that violated alignment
requirements. Known issues have now been fixed.
Committing on behalf of Lei Huang.
Differential Revision: https://reviews.llvm.org/D26861
llvm-svn: 301892
This commit caused some miscompiles that did not show up on any of the bots.
Reverting until we can investigate the cause of those failures.
llvm-svn: 288214
Currently we have a number of tests that fail with -verify-machineinstrs.
To detect this cases earlier we add the option to the testcases with the
exception of tests that will currently fail with this option. PR 27456 keeps
track of this failures.
No code review, as discussed with Hal Finkel.
llvm-svn: 277624
This patch corresponds to review:
http://reviews.llvm.org/D18592
It allows the PPC back end to generate the xxspltw instruction where we
previously only emitted vspltw.
llvm-svn: 268516
The initial code drop for VSX swap optimization permitted the
optimization only when all operations in a web of related computation
are lane-insensitive. For some lane-sensitive operations, we can
still permit the optimization provided that we make adjustments to
those operations. This patch adds special handling for vector splats
so that their presence doesn't kill the optimization.
Vector splats are lane-sensitive since they identify by number a
vector element to be used as the source of a splat. When swap
optimizations take place, the desired vector element will move to the
opposite doubleword of the quadword vector. We thus replace the index
I by (I + N/2) % N, where N is the number of elements in the vector.
A new test case is added to test that swap optimization succeeds when
vector splats are present, and that the proper input element is used
as the source of the splat.
An ancillary change removes SH_BUILDVEC as one of the kinds of special
handling that may be required by VSX swap optimization. From
experience with GCC, I had expected to need some modifications for
vector build operations, but I did not find that to be the case.
llvm-svn: 236606
Nemanja Ivanovic