102 Commits

Author SHA1 Message Date
Craig Topper
29463612d2 [RISCV] Replace RISCV -> RISC-V in comments. NFC
To be consistent with RISC-V branding guidelines
https://riscv.org/about/risc-v-branding-guidelines/
Think we should be using RISC-V where possible.

More patches will follow.

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D146449
2023-03-27 09:50:17 -07:00
Francesco Petrogalli
ee6d07fae2 [Target][RISCV] Update SubtargetFeature definition for RV32/RV64 (NFCI).
This is done for consistency with other Predicate/Subtargetfeature
pairs, where the second parameter of the SubtargetFeature correspond
to the NAME of the def of the Predicate associated to the
SubtargetFeature.

Differential Revision: https://reviews.llvm.org/D146129
2023-03-17 08:49:45 +01:00
Craig Topper
22b564c64b [RISCV] Add preferred function and loop alignment RISCVSubtarget. NFC
These seem like properties we will want to adjust based on -mtune.
Move them to subtarget like is done on ARM and AArch64. Don't add
any overrides yet.

Note there's a slight change here. We are now passing Align(1) for
preferred function alignment where we previously passed the minimum
alignment. As far as I could tell, it will be maxed with min when
it used so this should be ok.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D144048
2023-02-17 08:43:40 -08:00
Roland McGrath
34b21e817f [RISCV] Use OS-specific stack-guard ABI for Fuchsia
Fuchsia provides a slot relative to tp for the stack-guard value,
which is cheaper to materialize than the default GOT load.

Reviewed By: phosek

Differential Revision: https://reviews.llvm.org/D143353
2023-02-05 18:45:59 -08:00
Craig Topper
5c126e35c1 [RISCV] Remove RISCVSubtarget::getArchMinVLen()/getArchMaxVLen().
Fold them into their only callers, getRealMinVLen()/getArchMaxVLen().

It is unclear right now when these are needed so removing to discourage
misuse.

Between Zvl*b extensions, vector length command line options, and
vscale range, we have several ways to influence vector length. We
need to try to keep all code on the same page.
2023-01-10 15:32:11 -08:00
Craig Topper
011cbb3912 [RISCV] Move -riscv-v-vector-bits-max/min options to RISCVTargetMachine.
Split from D139873.

Reviewed By: reames, kito-cheng

Differential Revision: https://reviews.llvm.org/D140283
2022-12-20 11:55:33 -08:00
Craig Topper
7e2fbf6f7d [RISCV] Simplify RISCVSubtarget. NFC
The flags, initialization of the flags, and the getter methods for
features defined in RISCV.td can be generated by TableGen.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D139746
2022-12-09 16:26:16 -08:00
Craig Topper
66ff073182 [RISCV] Support F16 vectors with Zfhmin+Zvfh.
I've enabled Zfhmin on 2 basic tests to show this isn't
completely broken.

Reviewed By: monkchiang

Differential Revision: https://reviews.llvm.org/D139562
2022-12-07 19:14:11 -08:00
Monk Chiang
7b50c18360 [RISCV] Codegen support for Zfhmin.
The Zfhmin subset only has FLH, FSH, FMV.X.H, FMV.H.X, FCVT.S.H, and FCVT.H.S.
If the D extension is present, the FCVT.D.H and FCVT.H.D instructions are also included.
Since most instructions are not included for Zfhmin, so most operations are promoted.
The patch primarily about making f16 a legal type.

RISC-V ISA info:
https://wiki.riscv.org/display/HOME/Recently+Ratified+Extensions

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D139391
2022-12-06 22:14:15 -08:00
WuXinlong
0dbc52a0ab Add MC support of RISCV Zcd Extension
This patch add the instructions of Zcd extension.

Zcd is a subset of C Ext which include the double-precision floating-point instructions (c.fld, c.fldsp, c.fsd, c.fsdsp).

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D134177
2022-11-24 05:48:06 +08:00
WuXinlong
16bf359a3f Add MC support of RISCV Zcf Extension
This patch add the instructions of Zcf extension.

Zcf is a subset of C Ext which include the single-precision floating-point instructions.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D134176
2022-11-23 15:09:02 +08:00
WuXinlong
219417b2c6 [RISCV] Add CodeGen support and MC testcase of RISCV Zca Extension
This patch add the support of RISCV Zca ext

`Zca` is a subset of C extension instructions that are compatible with the Zc extension.

So this patch implements Zca code generation with reference to the C extension and sets the 2-byte alignment for the Zca extension, just like C extension does.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D130483
2022-11-22 17:22:26 +08:00
Philip Reames
780c539844 [RISCV] Implement assembler support for XVentanaCondOps
This change provides an implementation of the XVentanaCondOps vendor extension. This extension is defined in version 1.0.0 of the VTx-family custom instructions specification (https://github.com/ventanamicro/ventana-custom-extensions/releases/download/v1.0.0/ventana-custom-extensions-v1.0.0.pdf) by Ventana Micro Systems.

In addition to the technical contribution, this change is intended to be a test case for our vendor extension policy.

Once this lands, I plan to use this extension to prototype selection lowering to conditional moves. There's an RVI proposal in flight, and the expectation is that lowering to these and the new RVI instructions is likely to be substantially similar.

Differential Revision: https://reviews.llvm.org/D137350
2022-11-14 09:01:54 -08:00
wangpc
c66b69777c [RISCV] Don't use zero-stride vector load if there's no optimized u-arch
For vector strided instructions, as the RVV spec says:

> When rs2=x0, then an implementation is allowed, but not required, to
> perform fewer memory operations than the number of active elements, and
> may perform different numbers of memory operations across different
> dynamic executions of the same static instruction.

So compiler shouldn't assume that fewer memory operations will be
performed when rs2=x0.

We add a target feature to specify whether u-arch supports optimized
zero-stride vector load. And we do vector splat optimization iff this
feature is supported.

This feature is enabled by default since most designs implement this
optimization.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D137699
2022-11-14 13:51:30 +08:00
Piyou Chen
7d7940fd77 [RISCV] add svinval extension
1. Add the svinval extension support
2. Add the svinval Predicates for its instruction

Note: the svinval instructions defined in https://reviews.llvm.org/D117654

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D136571
2022-10-26 09:45:30 -07:00
Piyou Chen
f8b8426861 [RISCV] Add Svnapot extension
Reviewed By: kito-cheng

Differential Revision: https://reviews.llvm.org/D136570
2022-10-24 01:27:04 -07:00
Craig Topper
2b32e4f98b [RISCV] Add basic support for the sifive-7-series short forward branch optimization.
sifive-7-series has macrofusion support to convert a branch over
a single instruction into a conditional instruction. This can be
an improvement if the branch is hard to predict.

This patch adds support for the most basic case, a branch over a
move instruction. This is implemented as a pseudo instruction so
we can hide the control flow until all code motion passes complete.

I've disabled a recent select optimization if this feature is enabled
in the subtarget.

Related gcc patch for the same optimization https://www.mail-archive.com/gcc-patches@gcc.gnu.org/msg211045.html

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D135814
2022-10-17 13:56:22 -07:00
Craig Topper
52708be182 [RISCV] Remove support for the unratified Zbe, Zbf, and Zbm extensions.
These extensions do not appear to be on their way to ratification.
2022-09-22 13:04:41 -07:00
Craig Topper
182aa0cbe0 [RISCV] Remove support for the unratified Zbp extension.
This extension does not appear to be on its way to ratification.

Still need some follow up to simplify the RISCVISD nodes.
2022-09-21 21:22:42 -07:00
Craig Topper
70a64fe7b1 [RISCV] Remove support for the unratified Zbt extension.
This extension does not appear to be on its way to ratification.

Out of the unratified bitmanip extensions, this one had the
largest impact on the compiler.

Posting this patch to start a discussion about whether we should
remove these extensions. We'll talk more at the RISC-V sync meeting this
Thursday.

Reviewed By: asb, reames

Differential Revision: https://reviews.llvm.org/D133834
2022-09-20 20:26:48 -07:00
Philip Reames
eda2af575f [RISCV][MC] Add support for experimental Zawrs extension
This implements experimental support for the Zawrs extension as specified here: https://github.com/riscv/riscv-zawrs/releases/download/V1.0-rc3/Zawrs.pdf. Despite the 1.0 version name, this has not been ratified and there was a major change to proposed specification between rc2 and rc3.  Once this is ratified, it'll move out of experimental status.

This change adds assembly support, but does not include C language or IR intrinsics. We can decide if we want them, and handle that in a separate patch.

Differential Revision: https://reviews.llvm.org/D133443
2022-09-20 10:15:11 -07:00
Philip Reames
a4a29438f4 [RISCV][MC] Add minimal support for Ztso extension
This is a minimalist implementation which simply adds the extension (in the experimental namespace since its not ratified), and wires up the setting of the required ELF header flag. Future changes will include codegen changes to exploit the stronger memory model.

This is intended to implement v0.1 of the proposed specification which can be found in Chapter 25 of https://github.com/riscv/riscv-isa-manual/releases/download/draft-20220723-10eea63/riscv-spec.pdf.

Differential Revision: https://reviews.llvm.org/D133239
2022-09-07 09:30:57 -07:00
Craig Topper
e4177201eb [RISCV][M68k] Replace fixed size BitVector with std::bitset.
Saves a heap allocation and avoids an explicit call to the BitVector constructor.

Reviewed By: reames, myhsu

Differential Revision: https://reviews.llvm.org/D132674
2022-08-25 12:45:08 -07:00
Shao-Ce SUN
7167a4207e [RISCV] Add zihintntl instructions
Reviewed By: kito-cheng

Differential Revision: https://reviews.llvm.org/D121670
2022-08-22 12:06:30 +08:00
Craig Topper
37c47b2cac [RISCV] Change how mtune aliases are implemented.
The previous implementation translated from names like sifive-7-series
to sifive-7-rv32 or sifive-7-rv64. This also required sifive-7-rv32
and sifive-7-rv64 to be valid CPU names. As those are not real
CPUs it doesn't make sense to accept them in -mcpu.

This patch does away with the translation and adds sifive-7-series
directly to RISCV.td. Removing sifive-7-rv32 and sifive-7-rv64.
sifive-7-series is only allowed in -mtune.

I've also added "rocket" to RISCV.td but have not removed rocket-rv32
or rocket-rv64.

To prevent -mcpu=sifive-7-series or -mcpu=rocket being used with llc,
I've added a Feature32Bit to all rv32 CPUs. And made it an error to
have an rv32 triple without Feature32Bit. sifive-7-series and rocket
do not have Feature32Bit or Feature64Bit set so the user would need
to provide -mattr=+32bit or -mattr=+64bit along with the -mcpu to
avoid the error.

SiFive no longer names their newer products with 3, 5, or 7 series.
Instead we have p200 series, x200 series, p500 series, and p600 series.
Following the previous behavior would require a sifive-p500-rv32 and
sifive-p500-rv64 in order to support -mtune=sifive-p500-series. There
is currently no p500 product, but it could start getting confusing if
there was in the future.

I'm open to hearing alternatives for how to achieve my main goal
of removing sifive-7-rv32/rv64 as a CPU name.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D131708
2022-08-18 16:22:25 -07:00
WuXinlong
515ece1a90 [RISCV] Add MC support of RISCV Zca Extension
This patch adds support for part of Zc extension which will be frozen soon.

This extension is designed to continue reducing the binary size of RISC-V programs.
In this patch:
`Zca` is a subset of C extension instructions that are compatible with the Zc extension.

The spec of Zc ext is [[ https://github.com/riscv/riscv-code-size-reduction/releases | Here ]]

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D130141
2022-08-18 12:13:35 +08:00
Nikita Popov
f5ed0cb217 [RISCV] Add target feature to force-enable atomics
This adds a +forced-atomics target feature with the same semantics
as +atomics-32 on ARM (D130480). For RISCV targets without the +a
extension, this forces LLVM to assume that lock-free atomics
(up to 32/64 bits for riscv32/64 respectively) are available.

This means that atomic load/store are lowered to a simple load/store
(and fence as necessary), as these are guaranteed to be atomic
(as long as they're aligned). Atomic RMW/CAS are lowered to __sync
(rather than __atomic) libcalls. Responsibility for providing the
__sync libcalls lies with the user (for privileged single-core code
they can be implemented by disabling interrupts). Code using
+forced-atomics and -forced-atomics are not ABI compatible if atomic
variables cross the ABI boundary.

For context, the difference between __sync and __atomic is that the
former are required to be lock-free, while the latter requires a
shared global lock provided by a shared object library. See
https://llvm.org/docs/Atomics.html#libcalls-atomic for a detailed
discussion on the topic.

This target feature will be used by Rust's riscv32i target family
to support the use of atomic load/store without atomic RMW/CAS.

Differential Revision: https://reviews.llvm.org/D130621
2022-08-09 16:04:46 +02:00
ksyx
3198364e6e [RISCV][Clang] Add support for Zmmul extension
This patch implements recently ratified extension Zmmul, a subextension
of M (Integer Multiplication and Division) consisting only
multiplication part of it.

Differential Revision: https://reviews.llvm.org/D103313
Reviewed By: craig.topper, jrtc27, asb
2022-07-18 20:26:08 -04:00
Philip Reames
da60558d8a [RISCV] Rename getMin/MaxVLen to getArchMin/MaxVlen and make protected [nfc] 2022-06-28 15:54:40 -07:00
Alex Bradbury
7bcfcabbd1 [RISCV] Implement support for the Zicbop extension
Implements the ratified RISC-V Base Cache Management Operation ISA
Extension: Zicbop, as described in
https://github.com/riscv/riscv-CMOs/blob/master/specifications/cmobase-v1.0.pdf.

This is implemented in a separate patch to Zicbom and Zicboz due to it
requiring a new ASM operand type to be defined.

Differential Revision: https://reviews.llvm.org/D117433
2022-06-28 12:43:26 +01:00
Alex Bradbury
4f40ca53ce [RISCV] Implement support for the Zicbom and Zicboz extensions
Implements the ratified RISC-V Base Cache Management Operation ISA
Extensions: Zicbom and Zicboz, as described in
https://github.com/riscv/riscv-CMOs/blob/master/specifications/cmobase-v1.0.pdf.

Zicbop is implemented in a separate patch due to it requiring a new ASM
operand type to be defined.

As discussed in the relevant issue in the upstream spec
https://github.com/riscv/riscv-CMOs/issues/47, the cbo.* instructions
use the format (rs1) or 0(rs1) for their operand, similar to the AMOs.

Differential Revision: https://reviews.llvm.org/D117432
2022-06-28 12:43:25 +01:00
Philip Reames
767ba58f80 [RISCV] Make getMinRVVVectorSizeInBits and getMaxRVVVectorSizeInBits protected [nfc]
These are now only used in the implementation of getRealMinVLen and getRealMaxVLEn, and useRVVForFixedLengthVectors; make them protected to discourage new users.
2022-06-25 11:11:31 -07:00
Craig Topper
4045b62d4c [RISCV] Add macrofusion infrastructure and one example usage.
This adds the macrofusion plumbing and support fusing LUI+ADDI(W).

This is similar to D73643, but handles a different case. Other cases
can be added in the future.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D128393
2022-06-23 08:38:39 -07:00
Philip Reames
8a3b6ba756 [RISCV] Add a subtarget feature to enable unaligned scalar loads and stores
A RISCV implementation can choose to implement unaligned load/store support. We currently don't have a way for such a processor to indicate a preference for unaligned load/stores, so add a subtarget feature.

There doesn't appear to be a formal extension for unaligned support. The RISCV Profiles (https://github.com/riscv/riscv-profiles/blob/main/profiles.adoc#rva20u64-profile) docs use the name Zicclsm, but a) that doesn't appear to actually been standardized, and b) isn't quite what we want here anyway due to the perf comment.

Instead, we can follow precedent from other backends and have a feature flag for the existence of misaligned load/stores with sufficient performance that user code should actually use them.

Differential Revision: https://reviews.llvm.org/D126085
2022-05-26 15:25:47 -07:00
Zi Xuan Wu (Zeson)
861489af1b [NFC][RISCV] Enable TuneNoDefaultUnroll feature to control targets which use default unroll preference
In RISCVTargetTransformInfo, enumerating the processor family is not a good way to predict.
Because it needs to enumerate many subtarget family and is hard to update if add new subtarget.
Instead, create a feature to distinguish whether targets want to use default unroll preference or not.

Keep TuneSiFive7 because it's flag to indicate subtarget family, which may used in other place.

Differential Revision: https://reviews.llvm.org/D125741
2022-05-19 12:21:49 +08:00
Craig Topper
ed242b54c9 [RISCV] Enable subregister liveness tracking for RVV.
RVV makes heavy use of subregisters due to LMUL>1 and segment
load/store tuples. Enabling subregister liveness tracking improves the quality
of the register allocation.

I've added a command line that can be used to turn it off if it causes compile
time or functional issues. I used the command line to keep the old behavior
for one interesting test case that was testing register allocation.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D125108
2022-05-11 12:49:03 -07:00
Craig Topper
76192182d0 [RISCV] Remove riscv-v-fixed-length-vector-elen-max command line option.
This was added before Zve extensions were defined. I think users
should use Zve32x or Zve32f now. Though we will lose support for limiting
ELEN to 16 or 8, but I hope no one was using that.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D123418
2022-04-11 10:14:48 -07:00
Craig Topper
c266e50430 [RISCV] Remove ExtZvl enum from RISCVSubtarget. NFC
Having an enum with names that contain the string representation
of their value doesn't add any value. We can just use the numbers.

Reviewed By: kito-cheng, frasercrmck

Differential Revision: https://reviews.llvm.org/D123417
2022-04-11 10:01:17 -07:00
Craig Topper
bbd2ecf9f0 [RISCV] Add +experimental-zvfh extension to cover half types in vectors.
Currently we allow half types in vectors if the scalar Zfh extension
is enabled. This behavior is not inline with the vector spec. For f32
and f64 types, the Zve32f, Zve64f, Zve64d, and V explicitly control
the availablity of floating point types in vectors.

In order to make our compiler compliant, we either need to remove all support
for half in vectors or we need an extension to control it.

Draft spec here https://github.com/riscv/riscv-v-spec/pull/780

Reviewed By: kito-cheng

Differential Revision: https://reviews.llvm.org/D121345
2022-03-17 10:04:02 -07:00
Lehua Ding
1648852c98 [RISCV][RVV] Fix vslide1up/down intrinsics overflow bug for SEW=64 on RV32
Reviewed By: craig.topper, kito-cheng

Differential Revision: https://reviews.llvm.org/D120899
2022-03-13 18:06:09 +08:00
Shao-Ce SUN
0e38b29543 [RISCV] add the MC layer support of Zfinx extension
This patch added the MC layer support of Zfinx extension.

Authored-by: StephenFan
Co-Authored-by: Shao-Ce Sun

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D93298
2022-03-02 14:25:19 +08:00
Mircea Trofin
cb2160760e [nfc][codegen] Move RegisterBank[Info].h under CodeGen
This wraps up from D119053. The 2 headers are moved as described,
fixed file headers and include guards, updated all files where the old
paths were detected (simple grep through the repo), and `clang-format`-ed it all.

Differential Revision: https://reviews.llvm.org/D119876
2022-03-01 21:53:25 -08:00
Nikita Popov
c7fe6f9c92 Revert "[RISCV] add the MC layer support of Zfinx extension"
This reverts commit 7798ecca9c3db42241169d31fea4fb820ed01830.

As reported in https://reviews.llvm.org/D93298#3331641 and
following, this causes assertion failures with inline assembly.
2022-02-24 12:14:31 +01:00
Shao-Ce SUN
7798ecca9c [RISCV] add the MC layer support of Zfinx extension
This patch added the MC layer support of Zfinx extension.

Authored-by: StephenFan
Co-Authored-by: Shao-Ce Sun

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D93298
2022-02-17 21:54:13 +08:00
jacquesguan
bfb4c0c370 [RISCV] Recover the implication between Zve* extensions and the V extension.
This revision recover the implication between Zve* extensions and the V extension.

Differential Revision: https://reviews.llvm.org/D119210
2022-02-14 15:52:07 +08:00
Shao-Ce SUN
005fd8aa70 [RISCV] Add support for Zihintpause extention
Add support for the 'pause' hint instruction as an alias for
'fence w, 0'. To do this allow the 'fence' operands pred and succ
to be set to 0 (the empty set). This will also allow future hints
to be encoded as 'fence 0, <x>' and 'fence <x>, 0'.

This patch revised from @mundaym's D93019.

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D117789
2022-02-03 20:55:47 +08:00
Craig Topper
09606d6a63 [RISCV] Update the computeKnownBitsForTargetNode for RISCVISD::READ_VLENB to consider Zve/Zvl.
We had previously hardcoded this to assume that vector registers
are 128 bits. This was true when only V existed, but after Zve
extensions were added this became incorrect.

This patch adjusts it to support 128, 64, or 32 bit vectors depending
on Zvl. The 128-bit limit is artificial, but we don't have any test
coverage showing that we larger values so I was being conservative.

None of our lit tests depend on this code today due to the custom
lowering of ISD::VSCALE that inserts the appropriate left or right
shift to convert from VLENB to VSCALE. That code was added after
this code in computeKnownBitsForTargetNode.

Reviewed By: frasercrmck

Differential Revision: https://reviews.llvm.org/D118582
2022-01-31 09:13:14 -08:00
eopXD
b089e4072a [RISCV] Don't allow i64 vector div by constant to use mulh with Zve64x
EEW=64 of mulh and its vairants requires V extension.

Authored by: Craig Topper <craig.topper@sifive.com> @craig.topper

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D117947
2022-01-25 09:55:05 -08:00
SForeKeeper
70f83f3084 [RISCV] add support for zbkx subextension in MC layer.
This patch adds support for zbkx extension from K extension(v1.0.0) in MC layer.
Instructions with same functionality and same encoding is defined in the bitmanip extension.
It defines {Xperm8, Xperm4} as instruction aliases for xperm.* in Zbp extension. When Zbkx is enabled while Zbp is not, xperm.h will not be available. When Zbkx and Zbp are both enabled, the instructions will be decoded in Zbp format.

[[ https://reviews.llvm.org/D94999 | D94999 ]] this is the patch that introduces xperm.* instructions.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D117889
2022-01-24 20:38:46 +08:00
jacquesguan
ba16e3c31f [RISCV] Decouple Zve* extensions and the V extension.
According to the spec, there are some difference between V and Zve64d. For example, the vmulh integer multiply variants that return the high word of the product (vmulh.vv, vmulh.vx, vmulhu.vv, vmulhu.vx, vmulhsu.vv, vmulhsu.vx) are not included for EEW=64 in Zve64*, but V extension does support these instructions. So we should decouple Zve* extensions and the V extension.

Differential Revision: https://reviews.llvm.org/D117854
2022-01-24 14:55:21 +08:00