Commit Graph

12 Commits

Author SHA1 Message Date
Jim Lin 242ddd5089 [RISCV][NFC] Add a single space after comma for VType
In most of cases, it has a single space after comma in assembly operands.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D103790
2021-06-09 11:18:22 +08:00
Craig Topper c653711fd3 [RISCV] Teach vsetvli insertion pass that operations on masks don't care about SEW/LMUL.
All that really matters is that the VLMAX of the preceding
instructions is the same as the VLMAX required by the mask
operation.

Also update the vmsge(u) handling to use the SEW/LMUL we use for
other mask register operations. We were matching it to the compare
before. Some cases will be improve if we fix masked compares to
use tail agnostic policy. I think they ignore the tail policy
anyway.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D103299
2021-06-04 09:17:46 -07:00
Craig Topper 5a5219a0f9 [RISCV] Remove earlyclobber from compares with LMUL<=1.
Compares are considered a narrowing operation for register overlap.
I believe for LMUL<=1 they meet this exception to allow overlap

"The destination EEW is smaller than the source EEW and the overlap is in the
lowest-numbered part of the source register group"

Both the result and the sources will occupy a single register for
LMUL<=1 so the overlap would always be in the "lowest-numbered part".

Reviewed By: frasercrmck, HsiangKai

Differential Revision: https://reviews.llvm.org/D103336
2021-06-01 09:08:11 -07:00
Craig Topper 527cd01314 [RISCV] Teach vsetvli insertion to use vsetvl x0, x0 form when we can tell that VLMAX and AVL haven't changed.
This can help avoid needing a virtual register for the vsetvl output
when the AVL is X0. For other register AVLs it can shorter the live
range of the AVL register if it isn't needed later.

There's probably no advantage when AVL is a 5 bit immediate that
can use vsetivli. But do it anyway for consistency.

Reviewed By: rogfer01

Differential Revision: https://reviews.llvm.org/D103215
2021-05-27 10:11:38 -07:00
Craig Topper fdf10e6197 [RISCV] Use X0 as destination of inserted vsetvli when possible.
We aren't going to connect the result to anything so we might
as well avoid allocating a register.

Reviewed By: frasercrmck, HsiangKai

Differential Revision: https://reviews.llvm.org/D102031
2021-05-26 13:08:51 -07:00
Fraser Cormack 797e580db9 [RISCV][NFC] Simplify test run lines
Several tests had -verify-machineinstrs twice, and several tests were
explicitly specifying the default FileCheck prefix of CHECK.
2021-05-13 12:41:00 +01:00
Craig Topper ce6e4f27dd [RISCV] Use fractional LMULs for fixed length types smaller than riscv-v-vector-bits-min.
My thought process is that if v2i64 is an LMUL=1 type then v2i32
should be an LMUL=1/2 type. We limit the fractional LMUL so that
SEW=64 clips to LMUL=1, SEW=32 clips to LMUL=1/2, etc. This
ensures there's always a fractional LMUL available to truncate a type.
This does reduce the number of vsetvlis in some cases.

Some tests increase vsetvlis because the best container type for a
mask type is dependent on the LMUL+SEW that the mask was produced
from, but you can't tell that from the type. I think this is
something we need to solve this in the machine IR when optimizing
vsetvlis.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D101215
2021-05-11 09:42:48 -07:00
Craig Topper ce09dd54e6 [RISCV] Select 5 bit immediate for VSETIVLI during isel rather than peepholing in the custom inserter.
This adds a special operand type that is allowed to be either
an immediate or register. By giving it a unique operand type the
machine verifier will ignore it.

This perturbs a lot of tests but mostly it is just slightly different
instruction orders. Something bad did happen to some min/max reduction
tests. We're spilling vector registers when we weren't before.

Reviewed By: khchen

Differential Revision: https://reviews.llvm.org/D101246
2021-04-27 14:38:16 -07:00
Craig Topper 7ed01a420a [RISCV] Pad v4i1/v2i1/v1i1 stores with 0s to make a full byte.
As noted in the FIXME there's a sort of agreement that the any
extra bits stored will be 0.

The generated code is pretty terrible. I was really hoping we
could use a tail undisturbed trick, but tail undisturbed no
longer applies to masked destinations in the current draft
spec.

Fingers crossed that it isn't common to do this. I doubt IR
from clang or the vectorizer would ever create this kind of store.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D100618
2021-04-19 11:05:18 -07:00
Bradley Smith 9745dce8c3 [SelectionDAG][AArch64][SVE] Perform SETCC condition legalization in LegalizeVectorOps
This is currently performed in SelectionDAGLegalize, here we make it also
happen in LegalizeVectorOps, allowing a target to lower the SETCC condition
codes first in LegalizeVectorOps and then lower to a custom node afterwards,
without having to duplicate all of the SETCC condition legalization in the
target specific lowering.

As a result of this, fixed length floating point SETCC nodes can now be
properly lowered for SVE.

Differential Revision: https://reviews.llvm.org/D98939
2021-03-29 15:32:25 +01:00
Craig Topper efcdd598b7 [RISCV] Teach VSETVLI inserter to use VSETIVLI when possible.
We always create the VL operand using a register, but if we can
determine that it came from an ADDI X0, imm with a sufficiently
small immediate, we can use VSETIVLI.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D97332
2021-02-24 16:07:33 -08:00
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