The forwarding header is left in place because of its use in
`polly/lib/External/isl/interface/extract_interface.cc`, but I have
added a GCC warning about the fact it is deprecated, because it is used
in `isl` from where it is included by Polly.
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
Rework the change to prevent build failures. NFCI.
The failing code was submitted as
cf7a8305a2b4ddfd299c748136cb9a2960ef7089 and reverted via
8bd65e535fb33bc48805bafed8217b16a853e158.
The rework in this new commit prevents failures like the following:
FAILED: tools/clang/lib/Basic/CMakeFiles/obj.clangBasic.dir/Targets/RISCV.cpp.o
/usr/bin/c++ [bunch of non interesting stuff] -c <path-to>/llvm-project/clang/lib/Basic/Targets/RISCV.cpp
In file included from <path-to>/llvm-project/clang/lib/Basic/Targets/RISCV.cpp:19:
<path-to>/llvm-project/llvm/include/llvm/TargetParser/RISCVTargetParser.h:29:10: fatal error: llvm/TargetParser/RISCVTargetParserDef.inc: No such file or directory
29 | #include "llvm/TargetParser/RISCVTargetParserDef.inc"
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
These failures happen because the library LLVMTargetParser depends on
RISCVTargetParserTableGen, which is a tablegen target that generates
the list of CPUs in
llvm/TargetParser/RISCVTargetParserDef.inc. This *.inc file is
included by the public header file
llvm/TargetParser/RISCVTargetParser.h.
The header file llvm/TargetParser/RISCVTargetParser.h is also used in
components (clangDriver and clangBasic) that link into
LLVMTargetParser, but on some configurations such components might end
up being built before TargetParser is ready.
The fix is to make sure that clangDriver and clangBasic depend on the
tablegen target RISCVTargetParserTableGen, which generates the .inc
file whether or not LLVMTargetParser is ready.
WRT the original patch at https://reviews.llvm.org/D137517, this
commit is just adding RISCVTargetParserTableGen in the DEPENDS list of
clangDriver and clangBasic.
This patch removes the file `llvm/include/llvm/TargetParser/RISCVTargetParser.def` and replaces it with a tablegen-generated `.inc` file out of `llvm/lib/Target/RISCV/RISCV.td`.
The module system has been updated to make sure we can build clang/llvm with `-DLLVM_ENABLE_MODULES=On`
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D137517
For `-foo=bar`, getSpelling return `-foo=` which is exactly what we need from
the diagnostic. Drop `-` from the err_drv_unsupported_option_argument template.
This change makes `--` long option diagnostics more convenient.
Reviewed By: lenary
Differential Revision: https://reviews.llvm.org/D137659
We may need hosted Clang/LLVM to compile and `getHostCpuName`
can be used for native detection.
Tests are added in riscv-cpus.c just like what AArch64/PPC
have done.
Reviewed By: kito-cheng
Differential Revision: https://reviews.llvm.org/D136930
-gsplit-dwarf produces a .dwo file which will not be processed by the linker. If
.dwo files contain relocations, they will not be resolved. Therefore the
practice is that .dwo files do not contain relocations.
Address ranges and location description need to use forms/entry kinds indexing
into .debug_addr (DW_FORM_addrx/DW_RLE_startx_endx/etc), which is currently not
implemented.
There is a difficult-to-read MC error with -gsplit-dwarf with RISC-V for both -mrelax and -mno-relax.
```
% clang --target=riscv64-linux-gnu -g -gsplit-dwarf -c a.c
error: A dwo section may not contain relocations
```
We expect to fix -mno-relax soon, so report a driver error for -mrelax for now.
Link: https://github.com/llvm/llvm-project/issues/56642
Reviewed By: compnerd, kito-cheng
Differential Revision: https://reviews.llvm.org/D130190
1. Remove computeDefaultABIFromArch and add computeDefaultABI in
RISCVISAInfo.
2. Add parseFeatureBits which may used in D118333.
Differential Revision: https://reviews.llvm.org/D119250
Every generated IR has a corresponding target-abi value, so
encoding a non-empty value would improve the robustness and
correctness.
Reviewed By: asb, jrtc27, arichardson
Differential Revision: https://reviews.llvm.org/D105555
RISCVISAInfo::toFeatures needs to allocate strings using
ArgList::MakeArgString, but toFeatures lives in Support and
MakeArgString lives in Option.
toFeature only has one caller, so the simple fix is to have that
caller pass a lamdba that wraps MakeArgString to break the
dependency.
Differential Revision: https://reviews.llvm.org/D112032
How many place you need to modify when implementing a new extension for RISC-V?
At least 7 places as I know:
- Add new SubtargetFeature at RISCV.td
- -march parser in RISCV.cpp
- RISCVTargetInfo::initFeatureMap@RISCV.cpp for handling feature vector.
- RISCVTargetInfo::getTargetDefines@RISCV.cpp for pre-define marco.
- Arch string parser for ELF attribute in RISCVAsmParser.cpp
- ELF attribute emittion in RISCVAsmParser.cpp, and make sure it's in
canonical order...
- ELF attribute emittion in RISCVTargetStreamer.cpp, and again, must in
canonical order...
And now, this patch provide an unified infrastructure for handling (almost)
everything of RISC-V arch string.
After this patch, you only need to update 2 places for implement an extension
for RISC-V:
- Add new SubtargetFeature at RISCV.td, hmmm, it's hard to avoid.
- Add new entry to RISCVSupportedExtension@RISCVISAInfo.cpp or
SupportedExperimentalExtensions@RISCVISAInfo.cpp .
Most codes are come from existing -march parser, but with few new feature/bug
fixes:
- Accept version for -march, e.g. -march=rv32i2p0.
- Reject version info with `p` but without minor version number like `rv32i2p`.
Differential Revision: https://reviews.llvm.org/D105168
I've removed the Zbs W instructions that are not part of the frozen spec.
References to B as an extension name have been removed. Tests are updated or split accordingly.
Reviewed By: luismarques
Differential Revision: https://reviews.llvm.org/D110669
At this point it looks like a B extension will never exist. Instead
Zba, Zbb, Zbc, and Zbs are individual extensions being ratified
together as a package. Unknown at this time when or if the other
Zb* extensions will be ratified.
This patch removes references to the B extension. I've updated and
split tests accordingly.
This has been split from D110669 to make review a little easier.
Differential Revision: https://reviews.llvm.org/D111338
This consists of 3 compressed instructions, c.not, c.neg, and c.zext.w.
I believe these have been picked up by the Zce effort using different
encodings. I don't think it makes sense to keep them in bitmanip. It
will eventually cause a conflict if/when Zce is implemented in llvm.
Differential Revision: https://reviews.llvm.org/D110871
As v1.0-rc specs say Zvamo is removed from standard extension,
Zvamo has to be specified explicitly.
Reviewed By: evandro
Differential Revision: https://reviews.llvm.org/D105396
This is mostly a mechanical change, but a testcase that contains
parts of the StringRef class (clang/test/Analysis/llvm-conventions.cpp)
isn't touched.
Summary:
1. gcc uses `-march` and `-mtune` flag to chose arch and
pipeline model, but clang does not have `-mtune` flag,
we uses `-mcpu` to chose both infos.
2. Add SiFive e31 and u54 cpu which have default march
and pipeline model.
3. Specific `-mcpu` with rocket-rv[32|64] would select
pipeline model only, and use the driver's arch choosing
logic to get default arch.
Reviewers: lenary, asb, evandro, HsiangKai
Reviewed By: lenary, asb, evandro
Tags: #llvm, #clang
Differential Revision: https://reviews.llvm.org/D71124
Currently if two multi-letter extensions are provided in a -march=
string, the verification code checks the version of the first and
consumes the second, resulting in that part of the architecture
string being ignored. This adds a test that when a version number has
been parsed for an extension, there are no subsequent characters.
Differential Revision: https://reviews.llvm.org/D83819
This adds support for enabling experimental/unratified RISC-V ISA
extensions in the -march string in the case where an explicit version
number has been declared, and the -menable-experimental-extensions flag
has been provided.
This follows the design as discussed on the mailing lists in the
following RFC: http://lists.llvm.org/pipermail/llvm-dev/2020-January/138364.html
Since the RISC-V toolchain definition currently rejects any extension
with an explicit version number, the parsing logic has been tweaked to
support this, and to allow standard extensions to have their versions
checked in future patches.
The bitmanip 'b' extension has been added as a first use of this support,
it should easily extend to other as yet unratified extensions (such as
the vector 'v' extension).
Differential Revision: https://reviews.llvm.org/D73891
This patch adds the support required for using the __riscv_save and
__riscv_restore libcalls to implement a size-optimization for prologue
and epilogue code, whereby the spill and restore code of callee-saved
registers is implemented by common functions to reduce code duplication.
Logic is also included to ensure that if both this optimization and
shrink wrapping are enabled then the prologue and epilogue code can be
safely inserted into the basic blocks chosen by shrink wrapping.
Differential Revision: https://reviews.llvm.org/D62686
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
Summary:
Clang/LLVM is a cross-compiler, and so we don't have to make a choice
about `-march`/`-mabi` at build-time, but we may have to compute a
default `-march`/`-mabi` when compiling a program. Until now, each
place that has needed a default `-march` has calculated one itself.
This patch adds a single place where a default `-march` is calculated,
in order to avoid calculating different defaults in different places.
This patch adds a new function `riscv::getRISCVArch` which encapsulates
this logic based on GCC's for computing a default `-march` value
when none is provided. This patch also updates the logic in
`riscv::getRISCVABI` to match the logic in GCC's build system for
computing a default `-mabi`.
This patch also updates anywhere that `-march` is used to now use the
new function which can compute a default. In particular, we now
explicitly pass a `-march` value down to the gnu assembler.
GCC has convoluted logic in its build system to choose a default
`-march`/`-mabi` based on build options, which would be good to match.
This patch is based on the logic in GCC 9.2.0. This commit's logic is
different to GCC's only for baremetal targets, where we default
to rv32imac/ilp32 or rv64imac/lp64 depending on the target triple.
Tests have been updated to match the new logic.
Reviewers: asb, luismarques, rogfer01, kito-cheng, khchen
Reviewed By: asb, luismarques
Subscribers: sameer.abuasal, rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, shiva0217, jrtc27, MaskRay, zzheng, edward-jones, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, s.egerton, pzheng, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D69383
This adds support for reserving GPRs such that the compiler will not
choose a register for register allocation. The implementation follows
the same design as for AArch64; each reserved register becomes a target
feature and used for getting the reserved registers for a given
MachineFunction. The backend checks that it does not need to write to
any reserved register; if it does a relevant error is generated.
Differential Revision: https://reviews.llvm.org/D67185
When running clang as a native compiler in RISC-V Linux the flag
-mabi=ilp32d / -mabi=lp64d is always mandatory. This change makes it the
default there.
Differential Revision: https://reviews.llvm.org/D65634
llvm-svn: 371494
I plan to reuse it in a later patch.
This is almost NFC except a small change in control flow when diagnosing
+d without +f.
Differential Revision: https://reviews.llvm.org/D66002
llvm-svn: 371492
Summary:
LLVM issues a warning if passed unknown target features. Neither I nor
@asb noticed this until after https://reviews.llvm.org/D63498 landed.
This patch stops passing the (unknown) "save-restore" target feature to
the LLVM backend, but continues to emit a warning if a driver asks for
`-msave-restore`. The default of assuming `-mno-save-restore` (and
emitting no warnings) remains.
Reviewers: asb
Reviewed By: asb
Subscribers: rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, kito-cheng, shiva0217, jrtc27, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, cfe-commits, asb
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64008
llvm-svn: 364777
Summary:
The GCC RISC-V toolchain accepts `-msave-restore` and `-mno-save-restore`
to control whether libcalls are used for saving and restoring the stack within
prologues and epilogues.
Clang currently errors if someone passes -msave-restore or -mno-save-restore.
This means that people need to change build configurations to use clang. This
patch adds these flags, so that clang invocations can now match gcc.
As the RISC-V backend does not currently have a `save-restore` target feature,
we emit a warning if someone requests `-msave-restore`. LLVM does not error if
we pass the (unimplemented) target features `+save-restore` or `-save-restore`.
Reviewers: asb, luismarques
Reviewed By: asb
Subscribers: rbar, johnrusso, simoncook, apazos, sabuasal, niosHD, kito-cheng, shiva0217, jrtc27, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63498
llvm-svn: 364018
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
