(this is clang related part)
Without these explicit includes, removing other headers, who implicitly
include llvm-config.h, may have non-trivial side effects. For example,
`clagd` may report even `llvm-config.h` as "no used" in case it defines
a macro, that is explicitly used with #ifdef. It is actually amplified
with different build configs which use different set of macros.
* Move the setup_host_tool calls to the directories of their tool.
Although it works to call it in libclc, it can only appear in a single
location so it fails the "what if everyone did this?" test and causes
problems for downstream code that also wants to use native versions of
these tools from other projects.
* Correct the TARGET "${${tool}_target}" check. "${${tool}_target}" may
be set to the path to the executable, which works in dependencies but
cannot be tested using if(TARGET). For lack of a better alternative,
just check that "${${tool}_target}" is non-empty and trust that if it
is, it is set to a meaningful value. If somehow it turns out to be a
valid target, its value will still show up in error messages anyway.
* Account for llvm-spirv possibly being provided in-tree. Per
https://github.com/KhronosGroup/SPIRV-LLVM-Translator?tab=readme-ov-file#llvm-in-tree-build
it is possible to drop llvm-spirv into LLVM and have it built as part of
LLVM's build. In this configuration, cross builds of LLVM require a
native version of llvm-spirv to be built.
-Wa,-mmapsyms=implicit enables the alternative mapping symbol scheme
discussed at #99718.
While not conforming to the current aaelf64 ABI, the option is
invaluable for those with full control over their toolchain, no reliance
on weird relocatable files, and a strong focus on minimizing both
relocatable and executable sizes.
The option is discouraged when portability of the relocatable objects is
a concern.
https://maskray.me/blog/2024-07-21-mapping-symbols-rethinking-for-efficiency
elaborates the risk.
Pull Request: https://github.com/llvm/llvm-project/pull/104542
Fix the builds with LLVM_TOOL_LLVM_DRIVER_BUILD enabled.
LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES is not completely
compatible with export_executable_symbols as the later will be ignored
if the previous is set to NO.
Fix the issue by passing if symbols need to be exported to
llvm_add_exectuable so the link flag can be determined directly
without calling export_executable_symbols_* later.
`LLVM_ENABLE_EXPORTED_SYMBOLS_IN_EXECUTABLES` is not completely
compatible with `export_executable_symbols` as the later will be ignored
if the previous is set to NO.
Fix the issue by passing if symbols need to be exported to
`llvm_add_exectuable` so the link flag can be determined directly
without calling `export_executable_symbols_*` later.
bb83a3d introduced `--print-enabled-extensions` command line option for
AArch64. This patch introduces RISC-V support for this option. This patch
adds documentation for this option.
`riscvExtensionsHelp` is renamed to `printSupportedExtensions` to by
synonymous with AArch64 and so it is clear what that function does.
This introduces the new `--print-enabled-extensions` command line option
to AArch64, which prints the list of extensions that are enabled for the
target specified by the combination of `--target`/`-march`/`-mcpu`
values.
The goal of the this option is both to enable the manual inspection of
the enabled extensions by users and to enhance the testability of
architecture versions and CPU targets implemented in the compiler.
As part of this change, a new field for `FEAT_*` architecture feature
names was added to the TableGen entries. The output of the existing
`--print-supported-extensions` option was updated accordingly to show
these in a separate column.
This introduces the new `--print-enabled-extensions` command line option
to AArch64, which prints the list of extensions that are enabled for the
target specified by the combination of `--target`/`-march`/`-mcpu`
values.
The goal of the this option is both to enable the manual inspection of
the enabled extensions by users and to enhance the testability of
architecture versions and CPU targets implemented in the compiler.
As part of this change, a new field for `FEAT_*` architecture feature
names was added to the TableGen entries. The output of the existing
`--print-supported-extensions` option was updated accordingly to show
these in a separate column.
Also delete `AllowTemporaryLabels = true` from MCContext::reset: when
llc supports -save-temp-labels in the next change, this assignment
should be removed to support -compile-twice.
Commit 6c0665e221
(https://reviews.llvm.org/D45164) enabled certain constant expression
evaluation for `MCObjectStreamer` at parse time (e.g. `.if` directives,
see llvm/test/MC/AsmParser/assembler-expressions.s).
`getUseAssemblerInfoForParsing` was added to make `clang -c` handling
inline assembly similar to `MCAsmStreamer` (e.g. `llvm-mc -filetype=asm`),
where such expression folding (related to
`AttemptToFoldSymbolOffsetDifference`) is unavailable.
I believe this is overly conservative. We can make some parse-time
expression folding work for `clang -c` even if `clang -S` would still
report an error, a MCAsmStreamer issue (we cannot print `.if`
directives) that should not restrict the functionality of
MCObjectStreamer.
```
% cat b.cc
asm(R"(
.pushsection .text,"ax"
.globl _start; _start: ret
.if . -_start == 1
ret
.endif
.popsection
)");
% gcc -S b.cc && gcc -c b.cc
% clang -S -fno-integrated-as b.cc # succeeded
% clang -c b.cc # succeeded with this patch
% clang -S b.cc # still failed
<inline asm>:4:5: error: expected absolute expression
4 | .if . -_start == 1
| ^
1 error generated.
```
However, removing `getUseAssemblerInfoForParsing` would make
MCDwarfFrameEmitter::Emit (for .eh_frame FDE) slow (~4% compile time
regression for sqlite3.c amalgamation) due to expensive
`AttemptToFoldSymbolOffsetDifference`. For now, make
`UseAssemblerInfoForParsing` false in MCDwarfFrameEmitter::Emit.
Close#62520
Link: https://discourse.llvm.org/t/rfc-clang-assembly-object-equivalence-for-files-with-inline-assembly/78841
Pull Request: https://github.com/llvm/llvm-project/pull/91082
Commit 6c0665e221
(https://reviews.llvm.org/D45164) enabled certain constant expression
evaluation for `MCObjectStreamer` at parse time (e.g. `.if` directives,
see llvm/test/MC/AsmParser/assembler-expressions.s).
`getUseAssemblerInfoForParsing` was added to make `clang -c` handling
inline assembly similar to `MCAsmStreamer` (e.g. `llvm-mc -filetype=asm`),
where such expression folding (related to
`AttemptToFoldSymbolOffsetDifference`) is unavailable.
I believe this is overly conservative. We can make some parse-time
expression folding work for `clang -c` even if `clang -S` would still
report an error, a MCAsmStreamer issue (we cannot print `.if`
directives) that should not restrict the functionality of
MCObjectStreamer.
```
% cat b.cc
asm(R"(
.pushsection .text,"ax"
.globl _start; _start: ret
.if . -_start == 1
ret
.endif
.popsection
)");
% gcc -S b.cc && gcc -c b.cc
% clang -S -fno-integrated-as b.cc # succeeded
% clang -c b.cc # succeeded with this patch
% clang -S b.cc # still failed
<inline asm>:4:5: error: expected absolute expression
4 | .if . -_start == 1
| ^
1 error generated.
```
Close#62520
Link: https://discourse.llvm.org/t/rfc-clang-assembly-object-equivalence-for-files-with-inline-assembly/78841
Pull Request: https://github.com/llvm/llvm-project/pull/91082
This introduces a new file, RISCVISAUtils.cpp and moves the rest of
RISCVISAInfo to the TargetParser library.
This will allow us to generate part of RISCVISAInfo.cpp using tablegen.
Move CCC_OVERRIDE_OPTIONS support to clangDriver so that it may be used outside of the
clang driver binary.
The override functionality will be used in LLDB, to apply adjustments to ClangImporter
flags. This will be useful as an escape hatch when there are issues that can be fixed
by adding or removing clang flags.
The only thing changed is the name, from `ApplyQAOverride` to `applyOverrideOptions`.
The convention is for such MC-specific options to reside in
MCTargetOptions. However, CompressDebugSections/RelaxELFRelocations do
not follow the convention: `CompressDebugSections` is defined in both
TargetOptions and MCAsmInfo and there is forwarding complexity.
Move the option to MCTargetOptions and hereby simplify the code. Rename
the misleading RelaxELFRelocations to X86RelaxRelocations. llvm-mc
-relax-relocations and llc -x86-relax-relocations can now be unified.
`Driver::ClangExecutable` is derived from:
* (-canonical-prefixes default): `realpath` on the executable path
* (-no-canonical-prefixes) argv[0] (consult PATH if argv[0] is a word)
`Dir` and `ResourceDir` are derived from `ClangExecutable`. Both
variables are used to derive certain include and library paths.
`InstalledDir` is a related concept used to derive certain other paths.
`InstalledDir` is weird in the -canonical-prefixes mode: Clang
calls `make_absolute` but does not follow symlinks
(FIXME from 9ade6a9a74).
This causes some search and library paths to be mix-and-matched.
The "Do a PATH lookup, if there are no directory components." logic
makes things worse.
`InstalledDir` is different when you invoke it via `PATH`:
```
% which clang
/usr/bin/clang
% clang -v |& grep InstalledDir
InstalledDir: /usr/bin
% /usr/lib/llvm-16/bin/clang -v |& grep InstalledDir
InstalledDir: /usr/lib/llvm-16/bin
```
I believe `InstalledDir` was a partial solution to
`-no-canonical-prefixes` and should be eventually removed.
This patch removes `SetInstallDir` and relies on Driver::Driver to set
`InstalledDir` to `Dir`. The behavior for regular file `clang` or
`-no-canonical-prefixes` is unchanged.
If a user creates a symlink to the regular file `clang` and uses the
default `-canonical-prefixes`, they now consistently get search and
library paths relative to the regular file `clang`, not mix-and-match
paths.
If a user creates a symlink to the regular file `clang` and replaces
some directorys from the actual installation, they should change the
symlink to a wrapper that calls the underlying clang with
`-no-canonical-prefixes`.
PR #71709 broke the Linux PIE build with `undefined symbol: alloca`
errors. With the newly included `clang/Basic/Builtins.h` in that PR, it
surfaces an issue with a combination of two previous patches.
26670dcba1 added `#undef alloca` so clang
builtins handling of alloca would work under MSVC (unsure if this is
still necessary).
194b6a3b1b added code that calls `alloca`
to workaround a Linux kernel < 4.1 bug. Given that Linux 4.1 was EOL in
2018, it should be ok to remove this workaround.
Previously, some tools such as `clang` or `lld` which require strict
order for certain command-line options, such as `clang -cc1` or `lld
-flavor`, would not longer work on Windows, when these tools were linked
as part of `llvm-driver`. This was caused by `InitLLVM` which was part
of the `*_main()` function of these tools, which in turn calls
`windows::GetCommandLineArguments`. That function completly replaces
argc/argv by new UTF-8 contents, so any ajustements to argc/argv made by
`llvm-driver` prior to calling these tools was reset.
`InitLLVM` is now called by the `llvm-driver`. Any tool that
participates in (or is part of) the `llvm-driver` doesn't call
`InitLLVM` anymore.
This patch replaces uses of StringRef::{starts,ends}with with
StringRef::{starts,ends}_with for consistency with
std::{string,string_view}::{starts,ends}_with in C++20.
I'm planning to deprecate and eventually remove
StringRef::{starts,ends}with.
```
$ ./bin/clang --target=arm-linux-gnueabihf --print-supported-extensions
<...>
All available -march extensions for ARM
crc
crypto
sha2
aes
dotprod
<...>
```
This follows the format set by RISC-V and AArch64. As for AArch64, ARM
doesn't have versioned extensions like RISC-V does. So there is only 1
column, which contains the name.
Any extension without a "feature" is hidden as these cannot be used with
-march.
This follows the RISC-V work done in
4b40ced4e5.
This uses AArch64's target parser instead. We just list the names,
without the "+" on them, which matches RISC-V's format.
```
$ ./bin/clang -target aarch64-linux-gnu --print-supported-extensions
clang version 18.0.0 (https://github.com/llvm/llvm-project.git 154da8aec20719c82235a6957aa6e461f5a5e030)
Target: aarch64-unknown-linux-gnu
Thread model: posix
InstalledDir: <...>
All available -march extensions for AArch64
aes
b16b16
bf16
brbe
crc
crypto
cssc
<...>
```
Since our extensions don't have versions in the same way there's just
one column with the name in.
Any extension without a feature name (including the special "none") is
not listed as those cannot be passed to -march, they're just for the
backend. For example the MTE extension can be added with "+memtag" but
MTE2 and MTE3 do not have feature names so they cannot be added to
-march.
This does not attempt to tackle the fact that clang allows invalid
combinations of AArch64 extensions, it simply lists the possible
options. It's still up to the user to ask for something sensible.
Equally, this has no context of what CPU is being selected. Neither does
the RISC-V option, the user has to be aware of that.
I've added a target parser test, and a high level clang test that checks
RISC-V and AArch64 work and that Intel, that doesn't support this, shows
the correct error.
This revision supports --print-supported-extensions,
it prints out all of the extensions and corresponding version supported.
Reviewed By: craig.topper, kito-cheng
Differential Revision: https://reviews.llvm.org/D146054
This is a big refactor of the clang driver's option handling to use
the Visibility flags introduced in https://reviews.llvm.org/D157149.
There are a few distinct parts, but they can't really be split into
separate commits and still be made to compile.
1. We split out some of the flags in ClangFlags to ClangVisibility.
Note that this does not include any subtractive flags.
2. We update the Flag definitions and OptIn/OptOut constructs in
Options.td by hand.
3. We introduce and use a script, update_options_td_flags, to ease
migration of flag definitions in Options.td, and we run that on
Options.td. I intend to remove this later, but I'm committing it so
that downstream forks can use the script to simplify merging.
4. We update calls to OptTable in the clang driver, cc1as, flang, and
clangd to use the visibility APIs instead of Include/Exclude flags.
5. We deprecate the Include/Exclude APIs and add a release note.
*if you are running into conflicts with this change:*
Note that https://reviews.llvm.org/D157150 may also be the culprit and
if so it should be handled first.
The script in `clang/utils/update_options_td_flags.py` can help. Take
the downstream side of all conflicts and then run the following:
```
% cd clang/include/clang/Driver
% ../../../utils/update_options_td_flags.py Options.td > Options.td.new
% mv Options.td.new Options.td
```
This will hopefully be sufficient, please take a look at the diff.
Differential Revision: https://reviews.llvm.org/D157151
