156 Commits

Author SHA1 Message Date
Craig Topper
016eca8f90 [RISCV] Guard LowerINSERT_VECTOR_ELT against fixed vectors.
The type legalizer can call this code based on the scalar type so
we need to verify the vector type is a scalable vector.

I think due to how type legalization visits nodes, the vector type
will have already been legalized so we don't have an issue with
using MVT here like we did for EXTRACT_VECTOR_ELT.
I've added a test just in case.
2021-02-17 19:27:08 -08:00
Craig Topper
00c4e0a8f6 [RISCV] Guard the ISD::EXTRACT_VECTOR_ELT handling in ReplaceNodeResults against fixed vectors and non-MVT types.
The type legalizer is calling this code based on the scalar type so
we need to verify the input type is a scalable vector.

The vector type has also not been legalized yet when this is called
so we need to use EVT for it.
2021-02-17 18:25:38 -08:00
Fraser Cormack
d81161646a [RISCV] Add support for fixed vector vselect
This patch adds support for fixed-length vector vselect. It does so by
lowering them to a custom unmasked VSELECT_VL node with a vector length
operand.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D96768
2021-02-17 10:59:00 +00:00
Hsiangkai Wang
a3c783dbf2 [RISCV] Spilling for RISC-V V extension. (2nd version)
Differential Revision: https://reviews.llvm.org/D95148
2021-02-17 14:05:19 +08:00
Hsiangkai Wang
5a31a67385 [RISCV] Frame handling for RISC-V V extension.
This patch proposes how to deal with RISC-V vector frame objects. The
layout of RISC-V vector frame will look like

|---------------------------------|
| scalar callee-saved registers   |
|---------------------------------|
| scalar local variables          |
|---------------------------------|
| scalar outgoing arguments       |
|---------------------------------|
| RVV local variables &&          |
| RVV outgoing arguments          |
|---------------------------------| <- end of frame (sp)

If there is realignment or variable length array in the stack, we will use
frame pointer to access fixed objects and stack pointer to access
non-fixed objects.

|---------------------------------| <- frame pointer (fp)
| scalar callee-saved registers   |
|---------------------------------|
| scalar local variables          |
|---------------------------------|
| ///// realignment /////         |
|---------------------------------|
| scalar outgoing arguments       |
|---------------------------------|
| RVV local variables &&          |
| RVV outgoing arguments          |
|---------------------------------| <- end of frame (sp)

If there are both realignment and variable length array in the stack, we
will use frame pointer to access fixed objects and base pointer to access
non-fixed objects.

|---------------------------------| <- frame pointer (fp)
| scalar callee-saved registers   |
|---------------------------------|
| scalar local variables          |
|---------------------------------|
| ///// realignment /////         |
|---------------------------------| <- base pointer (bp)
| RVV local variables &&          |
| RVV outgoing arguments          |
|---------------------------------|
| /////////////////////////////// |
| variable length array           |
| /////////////////////////////// |
|---------------------------------| <- end of frame (sp)
| scalar outgoing arguments       |
|---------------------------------|

In this version, we do not save the addresses of RVV objects in the
stack. We access them directly through the polynomial expression
(a x VLENB + b). We do not reserve frame pointer when there is any RVV
object in the stack. So, we also access the scalar frame objects through the
polynomial expression (a x VLENB + b) if the access across RVV stack
area.

Differential Revision: https://reviews.llvm.org/D94465
2021-02-17 14:05:19 +08:00
Craig Topper
61a238e6e1 [RISCV] Add isel patterns for fixed vector fmsub/fnmadd/fnmsub. 2021-02-16 12:03:33 -08:00
Craig Topper
07ca13fe07 [RISCV] Add support for fixed vector mask logic operations.
Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D96741
2021-02-16 09:34:00 -08:00
Fraser Cormack
0264ee536b [RISCV] Remove unused CHECKs from recent test addition
These didn't show up as failures locally.
2021-02-16 10:33:33 +00:00
Fraser Cormack
04977ce5ce [RISCV] Fix a crash in fixed-length build_vector lowering
Non-splatted non-integer build_vector nodes were mistakenly being
lowered as VID expressions, which should not happen. VID can only be
used to select integer build_vector nodes.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D96718
2021-02-16 10:25:15 +00:00
Fraser Cormack
b870199020 [RISCV] Add patterns for scalable-vector fabs & fcopysign
The patterns mostly follow the scalar counterparts, save for some extra
optimizations to match the vector/scalar forms.

The patch adds a DAGCombine for ISD::FCOPYSIGN to try and reorder
ISD::FNEG around any ISD::FP_EXTEND or ISD::FP_TRUNC of the second
operand. This helps us achieve better codegen to match vfsgnjn.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D96028
2021-02-16 10:21:09 +00:00
Craig Topper
7ba2e1c601 [RISCV] Add support for fixed vector floating point setcc.
This is annoying because the condition code legalization belongs
to LegalizeDAG, but our custom handler runs in Legalize vector ops
which occurs earlier.

This adds some of the mask binary operations so that we can combine
multiple compares that we need for expansion.

I've also fixed up RISCVISelDAGToDAG.cpp to handle copies of masks.

This patch contains a subset of the integer setcc patch as well.
That patch is dependent on the integer binary ops patch. I'll rebase
based on what order the patches go in.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D96567
2021-02-15 12:52:25 -08:00
Craig Topper
4220a81c84 [RISCV] Add support for fixed vector fabs 2021-02-12 15:33:36 -08:00
Craig Topper
36658376d5 [RISCV] Add support for fixed vector sqrt. 2021-02-12 15:33:29 -08:00
Craig Topper
1697cc78b1 [RISCV] Add support for integer fixed vector setcc
I believe I've covered all orderings of splat operands here. Better
canonicalization in lowering might help reduce this. I did not handle
the immediate adjustments needed for set(u)gt/set(u)lt.

Testing here is limited to byte types because the scalable vector
type used for masks for the store is calculated assuming 8 byte
elements. But for the setcc its based on the element count of the
container type for the setcc input. So they don't agree. We'll need
to enhanced D96352 to handle this I think.

Differential Revision: https://reviews.llvm.org/D96443
2021-02-12 09:29:41 -08:00
Craig Topper
875c76de2b [RISCV] Add support for matching .vx and .vi forms of binary instructions for fixed vectors.
Unlike scalable vectors, I'm only using a ComplexPattern for
the immediate itself. The vmv_v_x is matched explicitly. We igore
the VL argument when matching a binary operator, but we do check
it when matching splat directly.

I left out tests for vXi64 as they fail on rv32 right now.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D96365
2021-02-12 09:18:10 -08:00
Fraser Cormack
e88da1d677 [RISCV] Add support for integer fixed min/max
This patch extends the initial fixed-length vector support to include
smin, smax, umin, and umax.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D96491
2021-02-12 09:19:45 +00:00
Craig Topper
7a7836b4d8 [RISCV] Add a pattern for a scalable vector mask vnot.
We can use a vnand.mm with the same register for both inputs.
This avoids materializing an alls ones constant with vmset.mm.
2021-02-11 15:34:58 -08:00
ShihPo Hung
9e62c9146d [RISCV] Initial support for insert/extract subvector
This patch handles cast-like insert_subvector & extract_subvector
in which case:
1. index starts from 0.
2. inserting a fixed-width vector into a scalable vector,
   or extracting a fixed-width vector from a scalable vector.

Reviewed By: craig.topper, frasercrmck

Differential Revision: https://reviews.llvm.org/D96352
2021-02-11 14:35:49 -08:00
Craig Topper
033b1bd185 [RISCV] Add support loads, stores, and splats of vXi1 fixed vectors.
This refines how we determine which masks types are legal and adds
support for loads, stores, and all ones/zeros splats.

I left a fixme in store handling where I think we need to zero
extra bits if the type isn't a multiple of a byte. If I remember
right from X86 there was some case we could have a store of a
1, 2, or 4 bit mask and have a scalar zextload that then expected the
bits to be 0. Its tricky to zero the bits with RVV. We need to do
something like round VL up, zero a register, lower the VL back down,
then do a tail undisturbed move into the zero register. Another
option might be to generate a mask of 1/2/4 bits set with a VL of 8
and use that to mask off the bits.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D96468
2021-02-11 09:13:16 -08:00
Craig Topper
cb161b3a88 [RISCV] Add support for matching .vf forms of fadd/fsub/fmul/fdiv/fma for fixed vectors.
fma+neg will come in a different patch since I haven't done it for .vv
yet either.

Differential Revision: https://reviews.llvm.org/D96375
2021-02-10 10:16:27 -08:00
Craig Topper
0c254b4a69 [RISCV] Add support for selecting vrgather.vx/vi for fixed vector splat shuffles.
The test cases extract a fixed element from a vector and splat it
into a vector. This gets DAG combined into a splat shuffle.

I've used some very wide vectors in the test to make sure we have
at least a couple tests where the element doesn't fit into the
uimm5 immediate of vrgather.vi so we fall back to vrgather.vx.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D96186
2021-02-10 10:01:56 -08:00
Fraser Cormack
a3c74d6d53 [RISCV] Add support for selecting vid.v from build_vector
This patch optimizes a build_vector "index sequence" and lowers it to
the existing custom RISCVISD::VID node. This pattern is common in
autovectorized code.

The custom node was updated to allow it to be used by both scalable and
fixed-length vectors, thus avoiding pattern duplication.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D96332
2021-02-10 10:58:40 +00:00
Hsiangkai Wang
a2d19bad07 [RISCV] Use whole register load/store for generic load/store.
In vector v0.10, there are whole vector register load/store
instructions. I suggest to use the whole register load/store
instructions for generic load/store for scalable vector types. It could
save up vset{i}vl{i} for these load/store.

For fractional LMUL, I keep to use vle{eew}.v/vse{eew}.v instructions to
load/store partial vector registers.

Differential Revision: https://reviews.llvm.org/D95853
2021-02-09 15:52:04 +08:00
Craig Topper
b49aaed8c7 [RISCV] Use _COMMUTABLE fma pseudos for fixed vectors.
This matches what we do in the VLMAX SDNode patterns.
2021-02-08 11:27:23 -08:00
Craig Topper
8d8cafa32e [RISCV] Add support for splat fixed length build_vectors using RVV.
Building on the fixed vector support from D95705

I've added ISD nodes for vmv.v.x and vfmv.v.f and switched to
lowering the intrinsics to it. This allows us to share the same
isel patterns for both.

This doesn't handle splats of i64 on RV32 yet. The build_vector
gets converted to a vXi32 build_vector+bitcast during type
legalization. Not sure the best way to handle this at the moment.

Differential Revision: https://reviews.llvm.org/D96108
2021-02-08 11:12:56 -08:00
Craig Topper
b8d719fbe8 [RISCV] Add support for fixed vector FMA.
Follow up to D95705. Does not include the commuting support from D95800.

Differential Revision: https://reviews.llvm.org/D96103
2021-02-08 11:12:56 -08:00
Craig Topper
a719b667a9 [RISCV] Add initial support for converting fixed vectors to scalable vectors during lowering to use RVV instructions.
This is an alternative to D95563.

This is modeled after a similar feature for AArch64's SVE that uses
predicated scalable vector instructions.a

Rather than use predication, this patch uses an explicit VL operand.
I've limited it to always use LMUL=1 for now, but we can improve this
in the future.

This requires a bunch of new ISD opcodes to carry the VL operand.
I think we can probably lower intrinsics to these ISD opcodes to
cut down on the size of the isel table. Which is why I've added
patterns for all integer/float types and not just LMUL=1.

I'm only testing one vector width right now, but the width is
programmable via the command line.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D95705
2021-02-08 10:41:30 -08:00
Craig Topper
b7b4f4cbc3 [RISCV] Make scalable vector FMA commutable for register allocation.
This adds support for commuting operands and converting between
vfmadd and vfmacc to avoid register copies.

To avoid messing up intrinsic behavior, I've added new pseudo
instructions that have the isCommutable flag set. These pseudos also
force a tail agnostic policy. The intrinsic version still use
the tail undisturbed policy.

For best results it looks like we need to start with fmadd and only
pick fmacc if its beneficial. MachineCSE commutes without contraining
the operands and then commutes back if it didn't help with CSE. So
I've made sure that when the operand choice isn't constrained, we
will keep fmadd for MachineCSE and when it does the second commute,
we get back the original instruction.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D95800
2021-02-08 10:05:33 -08:00
Fraser Cormack
b46aac125d [RISCV] Support the scalable-vector fadd reduction intrinsic
This patch adds support for both the fadd reduction intrinsic, in both
the ordered and unordered modes.

The fmin and fmax intrinsics are not currently supported due to a
discrepancy between the LLVM semantics and the RVV ISA behaviour with
regards to signaling NaNs. This behaviour is likely fixed in version 2.3
of the RISC-V F/D/Q extension, but until then the intrinsics can be left
unsupported.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D95870
2021-02-08 09:52:27 +00:00
Fraser Cormack
e046c0c28b [RISCV] Support scalable-vector integer reduction intrinsics
This patch adds support for the integer reduction intrinsics supported
by RVV. This excludes "mul" which has no corresponding instruction.

The reduction instructions in RVV have slightly complicated type
constraints given they always produce a single "M1" vector register.

They are lowered to custom nodes including the second "scalar" reduction
operand to simplify the patterns and in the hope that they can be useful
for future DAG combines.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D95620
2021-02-05 10:10:08 +00:00
Fraser Cormack
c3eb2da6c4 [RISCV] Optimize sign-extended EXTRACT_VECTOR_ELT nodes
This patch custom-legalizes all integer EXTRACT_VECTOR_ELT nodes where
SEW < XLEN to VMV_S_X nodes to help the compiler infer sign bits from
the result. This allows us to eliminate redundant sign extensions.

For parity, all integer EXTRACT_VECTOR_ELT nodes are legalized this way
so that we don't need TableGen patterns for some and not others.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D95741
2021-02-05 10:05:22 +00:00
Fraser Cormack
af48d2bfc2 [RISCV] Add patterns for scalable-vector fsqrt
This patch adds support for lowering the sqrt intrinsic to the RVV
vfsqrt instruction.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D96012
2021-02-05 09:39:19 +00:00
Craig Topper
6b280ce34c [RISCV] Use LLVMScalarOrSameVectorWidth to make avoid needing to mention the index type for vrgatherei16 intrinsics.
Add .vv to the intrinsic name to be consistent with D95979.

Reviewed By: khchen

Differential Revision: https://reviews.llvm.org/D95981
2021-02-04 20:26:45 -08:00
Craig Topper
25ff302a79 [RISCV] Split vrgather intrinsics into separate vrgather.vv and vrgather.vx intrinsics.
The vrgather.vv instruction uses a vector of indices with the same
SEW as operand 0. The vrgather.vx instructions use a scalar index
operand of XLen bits.

By splitting this into 2 intrinsics we are able to use LLVMatchType
in the definition to avoid specifying the type for the index operand
when creating the IR for the intrinsic. For .vv it will match the
operand 0 type. And for .vx it will match the type of the vl operand
we already needed to specify a type for.

I'm considering splitting more intrinsics. This was a somewhat
odd one because the .vx doesn't use the element type, it always
use XLen.

Reviewed By: HsiangKai

Differential Revision: https://reviews.llvm.org/D95979
2021-02-04 19:50:12 -08:00
Hsiangkai Wang
63baeec66e [RISCV] Load/store vector mask types.
Use vle1.v/vse1.v to load/store vector mask types.

Differential Revision: https://reviews.llvm.org/D93364
2021-02-03 13:44:15 +08:00
Hsiangkai Wang
c7189ba785 [RISCV] Add new vector instructions in v0.10.
* Add new vector instructions in v0.10.
 - load/store for mask value vle1.v vse1.v
 - vsetivli for 0-31 immediate vector length.
* Rename vector instructions in v0.10.
 - vfrsqrte7 -> vfrsqrt7
 - vfrece7 -> vfrec7
* Reserve memory width encodings for EEW>128b.

Differential Revision: https://reviews.llvm.org/D95781
2021-02-03 13:28:58 +08:00
Fraser Cormack
b4106f9c7b [RISCV] Fix incorrect RVV sdiv/udiv lowering
Due to a clerical error, the sdiv operation was mapping to vdivu and
udiv to vdiv, when the opposite mapping is the correct one.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D95869
2021-02-02 18:35:53 +00:00
Craig Topper
72b31ad4b8 [RISCV] Add scalable vector support for floating point FMA instructions
A follow up patch will add support for commuting operands or
changing opcode to vfmacc and friends.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D95662
2021-02-01 09:52:43 -08:00
Fraser Cormack
c87dd614fd [RISCV] Update extractelt tests to sign-extend results (NFC)
This demonstrates a missed optimization: the `vmv.x.s` instruction is
used to extract the element from the vector, and this instruction
already sign-extends the value to XLEN.
2021-01-30 15:50:07 +00:00
Craig Topper
ad5307aaca [RISCV] Merge rv32 and rv64 vector fadd/fsub/fmul/fdiv sdnode tests into single tests files with 2 run lines.
The IR and CHECK lines are identical so just keep one copy.
2021-01-29 17:32:08 -08:00
Craig Topper
ae82a8c863 [RISCV] Add support for scalable vector fneg using vfsgnjn.vv
Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D95568
2021-01-28 09:11:49 -08:00
Fraser Cormack
fc2f27ccf3 [RISCV] Add support for RVV int<->fp & fp<->fp conversions
This patch adds support for the full range of vector int-to-float,
float-to-int, and float-to-float conversions on legal types.

Many conversions are supported natively in RVV so are lowered with
patterns. These include conversions between (element) types of the same
size, and those that are half/double the size of the input. When
conversions take place between types that are less than half or more
than double the size we must lower them using sequences of instructions
which go via intermediate types.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D95447
2021-01-28 09:50:32 +00:00
Craig Topper
bfc60acd98 [RISCV] Adjust RISCVInstrInfoVSDPatterns.td for different pseudo instructions for different FPR.
Move the Suffix string into the VTypeInfo class so we don't need a helper class to get to it.

Adjust pseudo naming scheme for FPRs to put F16/F32/F64 in
place of F in the pseudo instruction name rather than as a suffix.
This avoids special cases like VFMERGE from the original patch.

Differential Revision: https://reviews.llvm.org/D95404
2021-01-26 01:00:50 -08:00
Hsiangkai Wang
e72b22a40b [RISCV] Define different pseudo instructions for different FPR.
When spilling, the spill size will depend on the size of register class.
For .vf vector instructions, it may spill the floating point scalar
argument. In order to use the correct load/store instructions for
spilling, we need to provide the correct floating point register class
for the .vf vector pseudo instructions.

In this commit, we define the .vf pseudo instructions as three
different kinds of pseudo instructions for half/float/double. For
example, PseudoVFADD_M1 will become as PseudoVFADD_F16_M1,
PseudoVFADD_F32_M1, and PseudoVFADD_F64_M1.

Differential Revision: https://reviews.llvm.org/D95234
2021-01-26 15:48:35 +08:00
Hsiangkai Wang
b69932b550 [RISCV] Implement vlsegff intrinsics.
Differential Revision: https://reviews.llvm.org/D95303
2021-01-26 12:02:43 +08:00
Fraser Cormack
15141cd115 [RISCV] Add RVV insertelt/extractelt scalable-vector patterns
Original patch by @rogfer01.

This patch adds support for insertelt and extractelt operations on
scalable vectors.

Special care must be taken on RV32 when dealing with i64 vectors as
there are no straightforward ways to insert a 64-bit element without a
register of that size. To that end, both are custom-lowered to different
sequences.

Authored-by: Roger Ferrer Ibanez <rofirrim@gmail.com>
Co-Authored-by: Fraser Cormack <fraser@codeplay.com>

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D94615
2021-01-25 22:03:52 +00:00
Fraser Cormack
fde2466171 [SelectionDAG] Support scalable-vector splats in more cases
This patch adds support for scalable-vector splats in DAGCombiner's
`isConstantOrConstantVector` and `ISD::matchUnaryPredicate` functions,
which enable the SelectionDAG div/rem-by-constant optimizations for
scalable vector types.

It also fixes up one case where the UDIV optimization was generating a
SETCC without first consulting the target for its preferred SETCC result
type.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D94501
2021-01-25 10:58:15 +00:00
Hsiangkai Wang
dc94cecac0 [RISCV] Add RV64 test cases for vsoxseg.
Differential Revision: https://reviews.llvm.org/D95195
2021-01-23 08:54:56 +08:00
Hsiangkai Wang
408ed11c85 [RISCV] Add RV32 test cases for vsoxseg.
Differential Revision: https://reviews.llvm.org/D95194
2021-01-23 08:54:56 +08:00
Hsiangkai Wang
438e118c29 [RISCV] Add RV64 test cases for vsuxseg.
Differential Revision: https://reviews.llvm.org/D95197
2021-01-23 08:54:56 +08:00