9 Commits

Author SHA1 Message Date
Craig Topper
9b0f227d7b [TableGen][RISCV] Add InstAliases with zero_reg to cover unmasked vnot.v, vncvt.x.x.w, vneg.v, etc.
The mask being NoRegister prevented the existing aliases from matching
since NoRegister isn't in the VMV0 register class.

To workaround this I've added new aliases that look for zero_reg.
I had to motify tablegen to generate matching code for zero_reg.
And as a consequence, I had to change the EmitPriority for an ARM
alias that used zero_reg that started printing.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D121496
2022-03-22 10:14:43 -07:00
Lian Wang
214afc7116 [RISCV] Add patterns for vnsrl.wi and vnsra.wi instructions
Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D121675
2022-03-17 07:22:32 +00:00
Craig Topper
b3bec6e453 [RISCV] Use vnsrl.wx with x0 instead of vnsrl.vi for truncate.
This matches what the spec uses for the vncvt.x.x.w assembly
pseudoinstruction.

Reviewed By: kito-cheng

Differential Revision: https://reviews.llvm.org/D118295
2022-01-26 18:38:13 -08:00
eopXD
3cf15af2da [RISCV] Remove experimental prefix from rvv-related extensions.
Extensions affected: +v, +zve*, +zvl*

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D117860
2022-01-22 20:18:40 -08:00
eopXD
8eae99dfe5 [RISCV] Add the zve extension according to the v1.0 spec
`zve` is the new standard vector extension to specify varying degrees of
vector support for embedding processors. The `zve` extension is related
to the `zvl` extension and other updates that are added in v1.0.

According to https://github.com/riscv-non-isa/riscv-c-api-doc/pull/21,
Clang defines macro `__riscv_v_max_elen`,  `__riscv_v_max_elen_fp` for
`zve` and it can be used by applications that uses the vector extension.

Authored by: Zakk Chen <zakk.chen@sifive.com> @khchen
Co-Authored by: Eop Chen <eop.chen@sifive.com> @eopXD

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D112408
2022-01-19 23:48:28 -08:00
wangpc
41454ab256 [RISCV] Use constant pool for large integers
For large integers (for example, magic numbers generated by
TargetLowering::BuildSDIV when dividing by constant), we may
need about 4~8 instructions to build them.
In the same time, it just takes two instructions to load
constants (with extra cycles to access memory), so it may be
profitable to put these integers into constant pool.

Reviewed By: asb, craig.topper

Differential Revision: https://reviews.llvm.org/D114950
2021-12-31 14:48:48 +08:00
wangpc
af0ecfccae [RISCV] Generate pseudo instruction li
Add an alias of `addi [x], zero, imm` to generate pseudo
instruction li, which makes assembly mush more readable.
For existed tests, users can update them by running script
`llvm/utils/update_llc_test_checks.py`.

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D112692
2021-11-22 14:01:37 +08:00
Craig Topper
0274be28d7 [RISCV] Lower vector CTLZ_ZERO_UNDEF/CTTZ_ZERO_UNDEF by converting to FP and extracting the exponent.
If we have a large enough floating point type that can exactly
represent the integer value, we can convert the value to FP and
use the exponent to calculate the leading/trailing zeros.

The exponent will contain log2 of the value plus the exponent bias.
We can then remove the bias and convert from log2 to leading/trailing
zeros.

This doesn't work for zero since the exponent of zero is zero so we
can only do this for CTLZ_ZERO_UNDEF/CTTZ_ZERO_UNDEF. If we need
a value for zero we can use a vmseq and a vmerge to handle it.

We need to be careful to make sure the floating point type is legal.
If it isn't we'll continue using the integer expansion. We could split the vector
and concatenate the results but that needs some additional work and evaluation.

Differential Revision: https://reviews.llvm.org/D111904
2021-11-17 10:29:41 -08:00
Craig Topper
d55be79d75 [RISCV] Expand scalable vector CTTZ/CTLZ/CTPOP.
Differential Revision: https://reviews.llvm.org/D112233
2021-10-21 10:50:04 -07:00