Correct references to alignment of store which may be deleted in a
previous iteration of merge. Instead use first store that would be
merged.
Corrects pr33172's use-after-poison caught by ASan.
Reviewers: spatel, hfinkel, RKSimon
Reviewed By: RKSimon
Subscribers: thegameg, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D33686
llvm-svn: 304299
There are some VectorShuffle Nodes in SDAG which can be selected to XXPERMDI
Instruction, this patch recognizes them and does the selection to improve
the PPC performance.
Differential Revision: https://reviews.llvm.org/D33404
llvm-svn: 304298
This patch builds upon https://reviews.llvm.org/rL302810 to add
handling for bitwise logical operations in general purpose registers.
The idea is to keep the values in GPRs as long as possible - only
extracting them to a condition register bit when no further operations
are to be done.
Differential Revision: https://reviews.llvm.org/D31851
llvm-svn: 304282
This is the equivalent of r304048 for ARM:
- Rewrite livein calculation to use the computeLiveIns() helper
function. This is slightly less efficient but easier to reason about
and doesn't unnecessarily add pristine and reserved registers[1]
- Zero the status register at the beginning of the loop to make sure it
has a defined value.
- Remove kill flags of values that need to stay alive throughout the loop.
[1] An upcoming commit of mine will tighten the MachineVerifier to catch
these.
llvm-svn: 304267
Summary:
AntiDepBreaker intends to add all live-outs, including the implicit
CSRs, in StartBlock. r299124 was done without understanding that
intention.
Now with the live-ins propagated correctly (D32464), we can revert this change.
Reviewers: MatzeB, qcolombet
Subscribers: nemanjai, llvm-commits
Differential Revision: https://reviews.llvm.org/D33697
llvm-svn: 304251
There is no guarantee that the first use of a constant that is traversed
is actually the first in the related basic block. Thus, if we use that
as the insertion point we may end up with definitions that don't
dominate there use.
llvm-svn: 304244
For multiplications of 64-bit values (giving 64-bit result), detect
cases where the arguments are sign-extended 32-bit values, on a per-
operand basis. This will allow few patterns to match a wider variety
of combinations in which extensions can occur.
llvm-svn: 304223
An encoding does not allow to use SDWA in an instruction with
scalar operands, either literals or SGPRs. That is however possible
to copy these operands into a VGPR first.
Several copies of the value are produced if multiple SDWA conversions
were done. To cleanup MachineLICM (to hoist copies out of loops),
MachineCSE (to remove duplicate copies) and SIFoldOperands (to replace
SGPR to VGPR copy with immediate copy right to the VGPR) runs are added
after the SDWA pass.
Differential Revision: https://reviews.llvm.org/D33583
llvm-svn: 304219
xchg with a mem operand has different locking semantics. If we unfold it
into a xchg r,r we will loose the implicit lock. Likewise we never want
to fold a register xchg into a memory one as it would be a lot slower.
This triggers during LLVM selfhost.
llvm-svn: 304163
The extending load possibility was missed in:
https://reviews.llvm.org/rL304072
We might want to handle this cases as a follow-up, but bailing out for now
to avoid miscompiling.
llvm-svn: 304153
Clang coerces structs into arrays, so it's a good idea to support them.
Most of the support boils down to getting the splitToValueTypes helper
to actually split types. We then use G_INSERT/G_EXTRACT to deal with the
parts.
llvm-svn: 304132
The reverted change introdued assertions ala:
"MachineBasicBlock::succ_iterator
llvm::MachineBasicBlock::removeSuccessor(succ_iterator, bool): Assertion
`I != Successors.end() && "Not a current successor!"'
Mikael, the original committer, wrote me that he is working on a fix, but that
it likely will take some time to get this resolved. As this bug is one of the
last two issues that keep the AOSP buildbot from turning green, I revert the
original commit r302876.
I am looking forward to see this recommitted after the assertion has been
resolved.
llvm-svn: 304128
This was reverted due to buildbot breakages and I was not familiar
with this code to investigate it. But while trying to get a
useful backtrace for the author, it turns out the fix was very
obvious. Resubmitting this patch as is, and will submit the
fix in a followup so that the fix is not hidden in the larger
CL.
llvm-svn: 304122
This reverts commit 28cb1003507f287726f43c771024a1dc102c45fe as well
as all subsequent followups. llvm-tblgen currently segfaults with
this change, and it seems it has been broken on the bots all
day with no fixes in preparation. See, for example:
http://lab.llvm.org:8011/builders/clang-x86-windows-msvc2015/
llvm-svn: 304121
X86 backend holds huge tables in order to map between the register and memory forms of each instruction.
This TableGen Backend automatically generated all these tables with the appropriate flags for each entry.
Differential Revision: https://reviews.llvm.org/D32684
llvm-svn: 304088
If we have (extract_subvector(load wide vector)) with no other users,
that can just be (load narrow vector). This is intentionally conservative.
Follow-ups may loosen the one-use constraint to account for the extract cost
or just remove the one-use check.
The memop chain updating is based on code that already exists multiple times
in x86 lowering, so that should be pulled into a helper function as a follow-up.
Background: this is a potential improvement noticed via regressions caused by
making x86's peekThroughBitcasts() not loop on consecutive bitcasts (see
comments in D33137).
Differential Revision: https://reviews.llvm.org/D33578
llvm-svn: 304072
Rewrite fixupKills() to use the LivePhysRegs class. Simplifies the code
and fixes a bug where the CSR registers in return blocks where missed
leading to invalid kill flags. Also remove the unnecessary rule that we
wouldn't set kill flags on tied operands.
No tests as I have an upcoming commit improving MachineVerifier checks
to catch these cases in multiple existing lit tests.
llvm-svn: 304055
This reverts commit r299287 plus clean-ups.
The localizer pass is a helper pass that could be run at O0 in the GISel
pipeline to work around the deficiency of the fast register allocator.
It basically shortens the live-ranges of the constants so that the
allocator does not spill all over the place.
Long term fix would be to make the greedy allocator fast.
llvm-svn: 304051
- Rewrite livein calculation to use the computeLiveIns() helper
function. This is slightly less efficient but easier to reason about
and doesn't unnecessarily add pristine and reserved registers[1]
- Zero the status register at the beginning of the loop to make sure it
has a defined value.
- Remove kill flags of values that need to stay alive throughout the loop.
[1] An upcoming commit of mine will tighten the MachineVerifier to catch
these.
llvm-svn: 304048
It's a workaround because the test was flakey passing to begin with, but
it looks like (going off commit history) it really did want to test in
the presence of debug info, so keep that behavior (by adding something
to the CU so it's not dropped) & restore the flakey pass in the process.
(added a FIXME in case someone else decides to look at it later)
llvm-svn: 304042
[AMDGPU] add intrinsic for s_getpc
Summary: The s_getpc instruction is exposed as intrinsic llvm.amdgcn.s.getpc.
Patch by Tim Corringham
llvm-svn: 304031
Re-commit r303938 and r303954 with a fix for addLiveIns(): the internal
addPristines() function must be called on an empty set or it may
accidentally reset saved registers.
- addLiveOutsNoPristines() needs to add callee saved registers that are
actually saved and restored somewhere to the set (they are not
pristine).
- Cleanup/rewrite the code for addLiveOuts()/addLiveOutsNoPristines().
This fixes the problem from D32156.
Differential Revision: https://reviews.llvm.org/D32464
llvm-svn: 304001
In the best case:
extract (binop (concat X1, X2), (concat Y1, Y2)), N --> binop XN, YN
...we kill all of the extract/concat and just have narrow binops remaining.
If only one of the binop operands is amenable, this transform is still
worthwhile because we kill some of the extract/concat.
Optional bitcasting makes the code more complicated, but there doesn't
seem to be a way to avoid that.
The TODO about extending to more than bitwise logic is there because we really
will regress several x86 tests including madd, psad, and even a plain
integer-multiply-by-2 or shift-left-by-1. I don't think there's anything
fundamentally wrong with this patch that would cause those regressions; those
folds are just missing or brittle.
If we extend to more binops, I found that this patch will fire on at least one
non-x86 regression test. There's an ARM NEON test in
test/CodeGen/ARM/coalesce-subregs.ll with a pattern like:
t5: v2f32 = vector_shuffle<0,3> t2, t4
t6: v1i64 = bitcast t5
t8: v1i64 = BUILD_VECTOR Constant:i64<0>
t9: v2i64 = concat_vectors t6, t8
t10: v4f32 = bitcast t9
t12: v4f32 = fmul t11, t10
t13: v2i64 = bitcast t12
t16: v1i64 = extract_subvector t13, Constant:i32<0>
There was no functional change in the codegen from this transform from what I
could see though.
For the x86 test changes:
1. PR32790() is the closest call. We don't reduce the AVX1 instruction count in that case,
but we improve throughput. Also, on a core like Jaguar that double-pumps 256-bit ops,
there's an unseen win because two 128-bit ops have the same cost as the wider 256-bit op.
SSE/AVX2/AXV512 are not affected which is expected because only AVX1 has the extract/concat
ops to match the pattern.
2. do_not_use_256bit_op() is the best case. Everyone wins by avoiding the concat/extract.
Related bug for IR filed as: https://bugs.llvm.org/show_bug.cgi?id=33026
3. The SSE diffs in vector-trunc-math.ll are just scheduling/RA, so nothing real AFAICT.
4. The AVX1 diffs in vector-tzcnt-256.ll are all the same pattern: we reduced the instruction
count by one in each case by eliminating two insert/extract while adding one narrower logic op.
https://bugs.llvm.org/show_bug.cgi?id=32790
Differential Revision: https://reviews.llvm.org/D33137
llvm-svn: 303997
Currently getOptimalMemOpType returns i32 for large enough sizes without
checking for alignment, leading to poor code generation when misaligned accesses
aren't permitted as we generate a word store then later split it up into byte
stores. This means we inadvertantly go over the MaxStoresPerMemcpy limit and for
memset we splat the memset value into a word then immediately split it up
again.
Fix this by leaving it up to FindOptimalMemOpLowering to figure out which type
to use, but also fix a bug there where it wasn't correctly checking if
misaligned memory accesses are allowed.
Differential Revision: https://reviews.llvm.org/D33442
llvm-svn: 303990
I forgot to forward the chain, causing some missing instruction
dependencies. The test crashes the compiler without this patch.
Inspired by the test case, D33519 also tries to remove the extra sync.
Differential Revision: https://reviews.llvm.org/D33573
llvm-svn: 303931
Rename the DEBUG_TYPE to match the names of corresponding passes where
it makes sense. Also establish the pattern of simply referencing
DEBUG_TYPE instead of repeating the passname where possible.
llvm-svn: 303921
