Commit Graph

5 Commits

Author SHA1 Message Date
Nemanja Ivanovic 6354d23555 [Power9] Exploit D-Form VSX Scalar memory ops that target full VSX register set
This patch corresponds to review:

The newly added VSX D-Form (register + offset) memory ops target the upper half
of the VSX register set. The existing ones target the lower half. In order to
unify these and have the ability to target all the VSX registers using D-Form
operations, this patch defines Pseudo-ops for the loads/stores which are
expanded post-RA. The expansion then choses the correct opcode based on the
register that was allocated for the operation.

llvm-svn: 283212
2016-10-04 11:25:52 +00:00
Nemanja Ivanovic 6e7879c5e6 [Power9] Add exploitation of non-permuting memory ops
This patch corresponds to review:
https://reviews.llvm.org/D19825

The new lxvx/stxvx instructions do not require the swaps to line the elements
up correctly. In order to select them over the lxvd2x/lxvw4x instructions which
require swaps, the patterns for the old instruction have a predicate that
ensures they won't be selected on Power9 and newer CPUs.

llvm-svn: 282143
2016-09-22 09:52:19 +00:00
Ehsan Amiri a538b0f023 Adding -verify-machineinstrs option to PowerPC tests
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
2016-08-03 18:17:35 +00:00
Bill Schmidt 34af5e1c76 [PowerPC] Add an MI SSA peephole pass.
This patch adds a pass for doing PowerPC peephole optimizations at the
MI level while the code is still in SSA form.  This allows for easy
modifications to the instructions while depending on a subsequent pass
of DCE.  Both passes are very fast due to the characteristics of SSA.

At this time, the only peepholes added are for cleaning up various
redundancies involving the XXPERMDI instruction.  However, I would
expect this will be a useful place to add more peepholes for
inefficiencies generated during instruction selection.  The pass is
placed after VSX swap optimization, as it is best to let that pass
remove unnecessary swaps before performing any remaining clean-ups.

The utility of these clean-ups are demonstrated by changes to four
existing test cases, all of which now have tighter expected code
generation.  I've also added Eric Schweiz's bugpoint-reduced test from
PR25157, for which we now generate tight code.  One other test started
failing for me, and I've fixed it
(test/Transforms/PlaceSafepoints/finite-loops.ll) as well; this is not
related to my changes, and I'm not sure why it works before and not
after.  The problem is that the CHECK-NOT: of "statepoint" from test1
fails because of the "statepoint" in test2, and so forth.  Adding a
CHECK-LABEL in between keeps the different occurrences of that string
properly scoped.

llvm-svn: 252651
2015-11-10 21:38:26 +00:00
Bill Schmidt 2be8054b49 [PPC64LE] More vector swap optimization TLC
This makes one substantive change and a few stylistic changes to the
VSX swap optimization pass.

The substantive change is to permit LXSDX and LXSSPX instructions to
participate in swap optimization computations.  The previous change to
insert a swap following a SUBREG_TO_REG widening operation makes this
almost trivial.

I experimented with also permitting STXSDX and STXSSPX instructions.
This can be done using similar techniques:  we could insert a swap
prior to a narrowing COPY operation, and then permit these stores to
participate.  I prototyped this, but discovered that the pattern of a
narrowing COPY followed by an STXSDX does not occur in any of our
test-suite code.  So instead, I added commentary indicating that this
could be done.

Other TLC:
 - I changed SH_COPYSCALAR to SH_COPYWIDEN to more clearly indicate
 the direction of the copy.
 - I factored the insertion of swap instructions into a separate
 function.

Finally, I added a new test case to check that the scalar-to-vector
loads are working properly with swap optimization.

llvm-svn: 242838
2015-07-21 21:40:17 +00:00