81 Commits

Author SHA1 Message Date
Philip Reames
22e199e6af [RISCV] Accept zicsr and zifencei command line options
This change adds the definition of the two extensions, but does not either a) make any instruction conditional on them or b) enabled the extensions by default. (The *instructions* do remain enabled by default per ISA version 2.0 which is our current default.)

This is meant to be a building block towards something like https://reviews.llvm.org/D141666, and in the meantime, address one of the most surprising of the current user experience warts. The current behavior of rejecting the extensions at the command line despite emitting code which appears to use them is surprising to anyone not deeply versed in the details of this situation.

Between versions 2.0 and 2.1 of the base I specification, a backwards incompatible change was made to remove selected instructions and CSRs from the base ISA. These instructions were grouped into a set of new extensions (these), but were no longer required by the base ISA. This change is described in “Preface to Document Version 20190608-Base-Ratified” from the specification document.

As LLVM currently implements only version 2.0 of the base specification, accepting these extensions at the command line introduces a configuration which doesn't actually match any spec version. It's a pretty harmless variant since the 2.0 extension definitions, to my knowledge, exactly match the text from the 2.0 I text before they were moved into standalone extensions in 2.1 of I. (The version numbering in that sentence is a tad confusing to say the least. Hopefully I got it right.)

It is worth noting that we already have numerous examples of accepting extensions in the march string which didn't exist in version of the spec document corresponding to our current base I version, so this doesn't set any new precedent.

Differential Revision: https://reviews.llvm.org/D143953
2023-02-16 10:41:41 -08:00
Manolis Tsamis
d4012bc43f [RISCV] Add vendor-defined XTheadMAC (multiply-accumulate) extension
The vendor-defined XTHeadMAC (no comparable standard extension exists
at the time of writing) extension adds multiply accumulate instructions.

It is supported by the C9xx cores (e.g., found in the wild in the
Allwinner D1) by Alibaba T-Head.

The current (as of this commit) public documentation for this
extension is available at:
  https://github.com/T-head-Semi/thead-extension-spec/releases/download/2.2.2/xthead-2023-01-30-2.2.2.pdf

Support for these instructions has already landed in GNU Binutils:
  https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=4041e11db3ec3611921d10150572a92689aa3154

Co-authored-by: Philipp Tomsich <philipp.tomsich@vrull.eu>

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D143847
2023-02-14 20:25:47 +01:00
Philipp Tomsich
fc02eeb24f [RISCV] Add vendor-defined XTheadBb (basic bit-manipulation) extension
The vendor-defined XTHeadBb (predating the standard Zbb extension)
extension adds some bit-manipulation extensions with somewhat similar
semantics as some of the Zbb instructions.

It is supported by the C9xx cores (e.g., found in the wild in the
Allwinner D1) by Alibaba T-Head.

The current (as of this commit) public documentation for XTHeadBb is
available from:
  https://github.com/T-head-Semi/thead-extension-spec/releases/download/2.2.2/xthead-2023-01-30-2.2.2.pdf

Support for these instructions has already landed in GNU Binutils:
  https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=8254c3d2c94ae5458095ea6c25446ba89134b9da

Depends on D143036

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D143439
2023-02-13 17:02:09 +01:00
Philipp Tomsich
04a2baf58f [RISCV] Add vendor-defined XTHeadBs (single-bit) extension
The vendor-defined XTHeadBs (predating the standard Zbs extension)
extension adds a bit-test instruction (th.tst) with similar semantics
as bexti from Zbs.  It is supported by the C9xx cores (e.g., found in
the wild in the Allwinner D1) by Alibaba T-Head.

The current (as of this commit) public documentation for XTHeadBs is
available from:
  https://github.com/T-head-Semi/thead-extension-spec/releases/download/2.2.2/xthead-2023-01-30-2.2.2.pdf

Support for these instructions has already landed in GNU Binutils:
  https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=8254c3d2c94ae5458095ea6c25446ba89134b9da

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D143036
2023-02-13 16:28:26 +01:00
Philipp Tomsich
0bda199285 Revert "[RISCV] Add vendor-defined XTHeadBs (single-bit) extension"
This reverts commit 656188ddc4075eb50260607b3497589873f373d2.
2023-02-08 08:00:45 +01:00
Philipp Tomsich
b0c3132226 Revert "[RISCV] Add vendor-defined XTheadBb (basic bit-manipulation) extension"
This reverts commit 19a59099095b3cbc9846e5330de26fca0a44ccbe.
2023-02-08 08:00:34 +01:00
Philipp Tomsich
19a5909909 [RISCV] Add vendor-defined XTheadBb (basic bit-manipulation) extension
The vendor-defined XTHeadBb (predating the standard Zbb extension)
extension adds some bit-manipulation extensions with somewhat similar
semantics as some of the Zbb instructions.

It is supported by the C9xx cores (e.g., found in the wild in the
Allwinner D1) by Alibaba T-Head.

The current (as of this commit) public documentation for XTHeadBb is
available from:
  https://github.com/T-head-Semi/thead-extension-spec/releases/download/2.2.2/xthead-2023-01-30-2.2.2.pdf

Support for these instructions has already landed in GNU Binutils:
  https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=8254c3d2c94ae5458095ea6c25446ba89134b9da

Depends on D143036

Differential Revision: https://reviews.llvm.org/D143439
2023-02-08 07:57:27 +01:00
Philipp Tomsich
656188ddc4 [RISCV] Add vendor-defined XTHeadBs (single-bit) extension
The vendor-defined XTHeadBs (predating the standard Zbs extension)
extension adds a bit-test instruction (th.tst) with similar semantics
as bexti from Zbs.  It is supported by the C9xx cores (e.g., found in
the wild in the Allwinner D1) by Alibaba T-Head.

The current (as of this commit) public documentation for XTHeadBs is
available from:
  https://github.com/T-head-Semi/thead-extension-spec/releases/download/2.2.2/xthead-2023-01-30-2.2.2.pdf

Support for these instructions has already landed in GNU Binutils:
  https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=8254c3d2c94ae5458095ea6c25446ba89134b9da

Depends on D143394

Differential Revision: https://reviews.llvm.org/D143036
2023-02-08 07:57:27 +01:00
Philipp Tomsich
e25b30d90a [RISCV] Add vendor-defined XTHeadBa (address-generation) extension
The vendor-defined XTHeadBa (predating the standard Zba extension)
extension adds an address-generation instruction (th.addsl) with
similar semantics as sh[123]add from Zba.  It is supported by the C9xx
cores (e.g., found in the wild in the Allwinner D1) by Alibaba T-Head.

The current (as of this commit) public documentation for XTHeadBa is
available from:
  https://github.com/T-head-Semi/thead-extension-spec/releases/download/2.2.2/xthead-2023-01-30-2.2.2.pdf

Support for these instructions has already landed in GNU Binutils:
  https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=8254c3d2c94ae5458095ea6c25446ba89134b9da

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D143029
2023-02-08 07:54:52 +01:00
Philipp Tomsich
9ac73d1251 [RISCV] Fix wrong comment style. NFC 2023-01-29 22:00:32 +01:00
Philipp Tomsich
4732e3cc1d [RISCV] Alphabetize X-extensions (and add a comment). NFC. 2023-01-29 21:55:12 +01:00
Craig Topper
3d7a59bdc0 [RISCV] Bump Zca, Zcb, Zcd, Zcf version to 1.0.
Differential Revision: https://reviews.llvm.org/D142596
2023-01-28 22:04:34 -08:00
WuXinlong
42c36da9c9 [RISCV] Add MC support of RISCV Zcb Extension
This patch add the instructions of Zcb extension.

Instructions in zcb extensions shorten part of bit manipulation instructions.

Co-authored-by: Craig Topper <craig.topper@sifive.com>

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D131141
2023-01-26 12:54:00 -08:00
Elena Lepilkina
31ee6ae059 [llvm-objdump] Fix reporting error for processing target features
Differential Revision: https://reviews.llvm.org/D142003
2023-01-18 16:56:51 +03:00
Elena Lepilkina
537cdf92c4 [llvm-objdump][RISCV] Use new common method to parse ARCH RISCV attribute
Differential Revision: https://reviews.llvm.org/D139553
2023-01-16 16:57:55 +03:00
Kito Cheng
f601039e81 [Driver][RISCV] Adjust the priority between -mcpu, -mtune and -march
RISC-V supports `-march`, `-mtune`, and `-mcpu`: `-march` provides the
architecture extension information, `-mtune` provide the pipeline model, and
`-mcpu` provides both.

What's the priority among those options for now(w/o this patch)?

Pipeline model:
- Take from `-mtune` if present.
- Take from `-mcpu` if present
- Use the default pipeline model: `generic-rv32` or `generic-rv64`
Architecture extension has quite complicated behavior now:
- Take union from `-march` and `-mcpu` if both are present.
- Take from `-march` if present.
- Take from `-mcpu` if present.
- Implied from `-mabi` if present.
- Use the default architecture depending on the target triple

We treat `-mcpu`/`-mtune` and `-mcpu`/`-march` differently, and it's
kind of counterintuitive: -march is explicitly specified but ignored.

This patch adjusts the priority between `-mcpu`/`-march`, letting it use
architecture extension information from `-march` if it's present.

So the priority of architecture extension information becomes:
- Take from `-march` if present.
- Take from `-mcpu` if present.
- Implied from `-mabi` if present.
- Use the default architecture depending on the target triple

And this also match what we implement in RISC-V GCC too.

Reviewed By: craig.topper, MaskRay

Differential Revision: https://reviews.llvm.org/D140693
2023-01-13 23:58:31 +08:00
Kito Cheng
f4c887c3a8 [RISCV] Add H extension
`h` was the prefix of multi-letter extension name, but it become a
extension name in later RISC-V isa spec.

Fortunately we don't have any extension really defined is prefixed
with `h`, so we can just change that.

Reviewed By: reames

Differential Revision: https://reviews.llvm.org/D136817
2023-01-10 09:52:03 +08:00
serge-sans-paille
38818b60c5
Move from llvm::makeArrayRef to ArrayRef deduction guides - llvm/ part
Use deduction guides instead of helper functions.

The only non-automatic changes have been:

1. ArrayRef(some_uint8_pointer, 0) needs to be changed into ArrayRef(some_uint8_pointer, (size_t)0) to avoid an ambiguous call with ArrayRef((uint8_t*), (uint8_t*))
2. CVSymbol sym(makeArrayRef(symStorage)); needed to be rewritten as CVSymbol sym{ArrayRef(symStorage)}; otherwise the compiler is confused and thinks we have a (bad) function prototype. There was a few similar situation across the codebase.
3. ADL doesn't seem to work the same for deduction-guides and functions, so at some point the llvm namespace must be explicitly stated.
4. The "reference mode" of makeArrayRef(ArrayRef<T> &) that acts as no-op is not supported (a constructor cannot achieve that).

Per reviewers' comment, some useless makeArrayRef have been removed in the process.

This is a follow-up to https://reviews.llvm.org/D140896 that introduced
the deduction guides.

Differential Revision: https://reviews.llvm.org/D140955
2023-01-05 14:11:08 +01:00
wangpc
c570287fbf [RISCV][NFC] Move RISCVISAInfo back to Support
So that there is no cyclic dependency if we want to use it in
tablegen.

Reviewed By: fpetrogalli

Differential Revision: https://reviews.llvm.org/D140529
2023-01-03 13:55:39 +08:00
Archibald Elliott
f09cf34d00 [Support] Move TargetParsers to new component
This is a fairly large changeset, but it can be broken into a few
pieces:
- `llvm/Support/*TargetParser*` are all moved from the LLVM Support
  component into a new LLVM Component called "TargetParser". This
  potentially enables using tablegen to maintain this information, as
  is shown in https://reviews.llvm.org/D137517. This cannot currently
  be done, as llvm-tblgen relies on LLVM's Support component.
- This also moves two files from Support which use and depend on
  information in the TargetParser:
  - `llvm/Support/Host.{h,cpp}` which contains functions for inspecting
    the current Host machine for info about it, primarily to support
    getting the host triple, but also for `-mcpu=native` support in e.g.
    Clang. This is fairly tightly intertwined with the information in
    `X86TargetParser.h`, so keeping them in the same component makes
    sense.
  - `llvm/ADT/Triple.h` and `llvm/Support/Triple.cpp`, which contains
    the target triple parser and representation. This is very intertwined
    with the Arm target parser, because the arm architecture version
    appears in canonical triples on arm platforms.
- I moved the relevant unittests to their own directory.

And so, we end up with a single component that has all the information
about the following, which to me seems like a unified component:
- Triples that LLVM Knows about
- Architecture names and CPUs that LLVM knows about
- CPU detection logic for LLVM

Given this, I have also moved `RISCVISAInfo.h` into this component, as
it seems to me to be part of that same set of functionality.

If you get link errors in your components after this patch, you likely
need to add TargetParser into LLVM_LINK_COMPONENTS in CMake.

Differential Revision: https://reviews.llvm.org/D137838
2022-12-20 11:05:50 +00:00
Kazu Hirata
405fc404bf [ADT] Don't including None.h (NFC)
These source files no longer use None, so they do not need to include
None.h.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2022-12-06 20:14:51 -08:00
Kazu Hirata
aadaaface2 [llvm] Use std::nullopt instead of None (NFC)
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated.  The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2022-12-02 21:11:44 -08:00
Kazu Hirata
7c421b53d1 [Support] Use std::optional in RISCVISAInfo.cpp (NFC)
This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2022-11-25 21:48:18 -08:00
Fangrui Song
bc0caabef5 RISCVISAInfo: Internalize struct FindByName 2022-11-23 17:22:49 -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
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
Kito Cheng
ae116f43ff [RISCV] Drop single letter b extension support
It splited into several zb* extensions, and `b` is dropped after
0.93, so it time to retired that as other non-ratified zb* extensions.

Currntly clang can accept that with warning:

$ clang -target riscv64-elf ~/hello.c -S  -march=rv64gcb
'+b' is not a recognized feature for this target (ignoring feature)
'+b' is not a recognized feature for this target (ignoring feature)
'+b' is not a recognized feature for this target (ignoring feature)

Reviewed By: asb, luismarques

Differential Revision: https://reviews.llvm.org/D136812
2022-10-27 23:53:32 +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
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
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
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
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
Kazu Hirata
109df7f9a4 [llvm] Qualify auto in range-based for loops (NFC)
Identified with readability-qualified-auto.
2022-08-13 12:55:42 -07:00
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
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
Shao-Ce SUN
1919adb19b [RISCV] Fix the problem of parsing long version numbers
For example, when parsing Zbpbo0p911, an error will be reported:
"multi-character extensions must be separated by underscores"

Reviewed By: asb

Differential Revision: https://reviews.llvm.org/D128644
2022-06-28 11:48:14 +08:00
Craig Topper
232c00ba5b [RISCV] Add extra space into error message about unsupported extension version.
Differential Revision: https://reviews.llvm.org/D125491
2022-05-12 12:56:29 -07:00
Tsukasa OI
7fe0630fcb [RISCV] 'K'-extension ordering
This commit adds 'K' to supported extension list (before 'J').
It makes "Zk*" extensions correctly placed before "Zv*" extensions.

Multi-letter "Z*" extensions are first ordered with the most closely
related alphabetical extension category ("IMAF...").  This is represented
in LLVM as `AllStdExts' variable in `llvm/lib/Support/RISCVISAInfo.cpp'.

However, it did not have 'k' making "Zk*" extensions not correctly ordered.

Reviewed By: kito-cheng

Differential Revision: https://reviews.llvm.org/D124340
2022-05-11 00:52:00 +08:00
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
eopXD
550b2eaaa6 [RISCV] Add combination crypto extensions in ISAInfo
The crypto extension have several shorthand extensions that don't consist of any extra instructions.
Take `zk` for example, while the extension would imply `zkn, zkr, zkt`. The 3 extensions should also
combine back into `zk` to maintain the canonical order in isa strings.

This patch addresses the above.

Reviewed By: VincentWu

Differential Revision: https://reviews.llvm.org/D119530
2022-03-08 09:52:38 -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
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
Zakk Chen
cfe7f69036 [RISCV][NFC] Refactor RISCVISAInfo.
1. Remove computeDefaultABIFromArch and add computeDefaultABI in
RISCVISAInfo.
2. Add parseFeatureBits which may used in D118333.

Differential Revision: https://reviews.llvm.org/D119250
2022-02-08 18:37:43 -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