Commit Graph

14 Commits

Author SHA1 Message Date
David Green c722575633 [ARM] Select VINS from vector inserts
This patch adds tablegen patterns for pairs of i16/f16 insert/extracts.
If we are inserting into two adjacent vector lanes (0 and 1 for
example), we can use either a vmov;vins or vmovx;vins to insert the pair
together, avoiding a round-trip from GRP registers. This is quite a
large patterns with a number of EXTRACT_SUBREG/INSERT_SUBREG/
COPY_TO_REGCLASS nodes, but hopefully as most of those become copies all
that will be cleaned up by further optimizations.

The VINS pattern was also adjusted to allow it to represent that it is
inserting into the top half of an existing register.

Differential Revision: https://reviews.llvm.org/D95381
2021-02-02 13:50:02 +00:00
David Green 40f46cb0e4 [ARM] Add alignment checks for MVE VLDn
The MVE VLD2/4 and VST2/4 instructions require the pointer to be aligned
to at least the size of the element type. This adds a check for that
into the ARM lowerInterleavedStore and lowerInterleavedLoad functions,
not creating the intrinsics if they are invalid for the alignment of
the load/store.

Unfortunately this is one of those bug fixes that does effect some
useful codegen, as we were able to sometimes do some nice lowering of
q15 types. But they can cause problem with low aligned pointers.

Differential Revision: https://reviews.llvm.org/D95319
2021-01-28 13:10:08 +00:00
David Green e841bd5f33 [ARM] Extra MVE unaligned VLDn tests. NFC 2021-01-24 21:39:00 +00:00
David Green e1c1adf9dc [ARM] Match dual lane vmovs from insert_vector_elt
MVE has a dual lane vector move instruction, capable of moving two
general purpose registers into lanes of a vector register. They look
like one of:
  vmov q0[2], q0[0], r2, r0
  vmov q0[3], q0[1], r3, r1
They only accept these lane indices though (and only insert into an
i32), either moving lanes 1 and 3, or 0 and 2.

This patch adds some tablegen patterns for them, selecting from vector
inserts elements. Because the insert_elements are know to be
canonicalized to ascending order there are several patterns that we need
to select. These lane indices are:

3 2 1 0    -> vmovqrr 31; vmovqrr 20
3 2 1      -> vmovqrr 31; vmov 2
3 1        -> vmovqrr 31
2 1 0      -> vmovqrr 20; vmov 1
2 0        -> vmovqrr 20

With the top one being the most common. All other potential patterns of
lane indices will be matched by a combination of these and the
individual vmov pattern already present. This does mean that we are
selecting several machine instructions at once due to the need to
re-arrange the inserts, but in this case there is nothing else that will
attempt to match an insert_vector_elt node.

This is a recommit of 6cc3d80a84 after
fixing the backward instruction definitions.
2020-12-18 16:13:08 +00:00
David Green 6e913e4451 Revert "[ARM] Match dual lane vmovs from insert_vector_elt"
This one needed more testing.
2020-12-18 13:33:40 +00:00
David Green 6cc3d80a84 [ARM] Match dual lane vmovs from insert_vector_elt
MVE has a dual lane vector move instruction, capable of moving two
general purpose registers into lanes of a vector register. They look
like one of:
  vmov q0[2], q0[0], r2, r0
  vmov q0[3], q0[1], r3, r1
They only accept these lane indices though (and only insert into an
i32), either moving lanes 1 and 3, or 0 and 2.

This patch adds some tablegen patterns for them, selecting from vector
inserts elements. Because the insert_elements are know to be
canonicalized to ascending order there are several patterns that we need
to select. These lane indices are:

3 2 1 0    -> vmovqrr 31; vmovqrr 20
3 2 1      -> vmovqrr 31; vmov 2
3 1        -> vmovqrr 31
2 1 0      -> vmovqrr 20; vmov 1
2 0        -> vmovqrr 20

With the top one being the most common. All other potential patterns of
lane indices will be matched by a combination of these and the
individual vmov pattern already present. This does mean that we are
selecting several machine instructions at once due to the need to
re-arrange the inserts, but in this case there is nothing else that will
attempt to match an insert_vector_elt node.

Differential Revision: https://reviews.llvm.org/D92553
2020-12-15 15:58:52 +00:00
David Green 6eee2d9b5b [ARM] Convert VDUPLANE to VDUP under MVE
Unlike Neon, MVE does not have a way of duplicating from a vector lane,
so a VDUPLANE currently selects to a VDUP(move_from_lane(..)). This
forces that to be done earlier as a dag combine to allow other folds to
happen.

It converts to a VDUP(EXTRACT). On FP16 this is then folded to a
VGETLANEu to prevent it from creating a vmovx;vmovhr pair, using a
single move_from_reg instead.

Differential Revision: https://reviews.llvm.org/D79606
2020-05-09 18:58:13 +01:00
David Green eecba95067 [ARM] Replace arm vendor with none. NFC 2020-04-22 18:19:35 +01:00
David Green c697dd9ffd [ARM] Make remaining MVE instruction predictable
The unpredictable/hasSideEffects flag is usually inferred by tablegen
from whether the instruction has a tablegen pattern (and that pattern
only has a single output instruction). Now that the MVE intrinsics are
all committed and producing code, the remaining instructions still
marked as unpredictable need to be specially handled. This adds the flag
directly to instructions that need it, notably the V*MLAL instructions
and some of the MOV's.

Differential Revision: https://reviews.llvm.org/D76910
2020-04-02 10:57:40 +01:00
David Green ff2e67a4f7 [ARM] MVE VLDn postinc
This adds Post inc variants of the VLD2/4 and VST2/4 instructions in
MVE. It uses the same mechanism/nodes as Neon, transforming the
intrinsic+add pair into a ARMISD::VLD2_UPD, which gets selected to a
post-inc instruction. The code to do that is mostly taken from the
existing Neon code, but simplified as less variants are needed.

It also fills in some getTgtMemIntrinsic for the arm.mve.vld2/4
instrinsics, which allow the nodes to have MMO's, calculated as the full
length to the memory being loaded/stored.

Differential Revision: https://reviews.llvm.org/D71194
2020-01-20 06:57:07 +00:00
Simon Pilgrim eb0e1978df [TargetLowering] SimplifyDemandedBits - call SimplifyMultipleUseDemandedBits for ISD::EXTRACT_VECTOR_ELT (REAPPLIED)
This patch attempts to peek through vectors based on the demanded bits/elt of a particular ISD::EXTRACT_VECTOR_ELT node, allowing us to avoid dependencies on ops that have no impact on the extract.

In particular this helps remove some unnecessary scalar->vector->scalar patterns.

The wasm shift patterns are annoying - @tlively has indicated that the wasm vector shift codegen are to be refactored in the near-term and isn't considered a major issue.

Reapplied after reversion at rL368660 due to PR42982 which was fixed at rGca7fdd41bda0.

Differential Revision: https://reviews.llvm.org/D65887
2020-01-04 13:15:50 +00:00
David Green 3a6eb5f160 [ARM] Disable VLD4 under MVE
Alas, using half the available vector registers in a single instruction
is just too much for the register allocator to handle. The mve-vldst4.ll
test here fails when these instructions are enabled at present. This
patch disables the generation of VLD4 and VST4 by adding a
mve-max-interleave-factor option, which we currently default to 2.

Differential Revision: https://reviews.llvm.org/D71109
2019-12-08 10:37:29 +00:00
David Green 882f23caea [ARM] MVE interleaving load and stores.
Now that we have the intrinsics, we can add VLD2/4 and VST2/4 lowering
for MVE. This works the same way as Neon, recognising the load/shuffles
combination and converting them into intrinsics in a pre-isel pass,
which just calls getMaxSupportedInterleaveFactor, lowerInterleavedLoad
and lowerInterleavedStore.

The main difference to Neon is that we do not have a VLD3 instruction.
Otherwise most of the code works very similarly, with just some minor
differences in the form of the intrinsics to work around. VLD3 is
disabled by making isLegalInterleavedAccessType return false for those
cases.

We may need some other future adjustments, such as VLD4 take up half the
available registers so should maybe cost more. This patch should get the
basics in though.

Differential Revision: https://reviews.llvm.org/D69392
2019-11-19 18:37:30 +00:00
David Green 411bfe476b [ARM] Add and update a lot of VLDn tests. NFC 2019-11-19 18:37:30 +00:00