The number of hardware threads available to a ThreadPool can be limited if setting an affinity mask.
For example:
> start /B /AFFINITY 0xF lld-link.exe ...
Would let LLD only use 4 hyper-threads.
Previously, there was an outstanding issue on Windows Server 2019 on dual-CPU machines, which was preventing from using both CPU sockets. In normal conditions, when no affinity mask was set, ProcessorGroup::AllThreads was different from ProcessorGroup::UsableThreads. The previous code in llvm/lib/Support/Windows/Threading.inc L201 was improperly assuming those two values to be equal, and consequently was limiting the execution to only one CPU socket.
Differential Revision: https://reviews.llvm.org/D92419
The number of hardware threads available to a ThreadPool can be limited if setting an affinity mask.
For example:
> start /B /AFFINITY 0xF lld-link.exe ...
Would let LLD only use 4 hyper-threads.
Previously, there was an outstanding issue on Windows Server 2019 on dual-CPU machines, which was preventing from using both CPU sockets. In normal conditions, when no affinity mask was set, ProcessorGroup::AllThreads was different from ProcessorGroup::UsableThreads. The previous code in llvm/lib/Support/Windows/Threading.inc L201 was improperly assuming those two values to be equal, and consequently was limiting the execution to only one CPU socket.
Differential Revision: https://reviews.llvm.org/D92419
The pipe signal handler must be installed before any other handlers are
registered. This is because the Unix RegisterHandlers function does not
perform a sigaction() for SIGPIPE unless a one-shot handler is present,
to allow long-lived processes (like lldb) to fully opt-out of llvm's
SIGPIPE handling and ignore the signal safely.
Fixes a bug introduced in D70277.
Tested by running Nick's test case:
% xcrun ./bin/clang -E -fno-integrated-cc1 x.c | tee foo.txt | head
I verified that child cc1 process exits with IO_ERR, and that the parent
recognizes the error code, exiting cleanly.
Differential Revision: https://reviews.llvm.org/D94324
Make llvm::Signpost more generic by untying from llvm::Timer. This
allows signposts to be used in a different context.
My motivation for doing this is being able to use signposts in LLDB.
Differential revision: https://reviews.llvm.org/D93655
Check if all possible values for a pair of knownbits give the same icmp result - these are based off the checks performed in InstCombineCompares.cpp and D86578.
Add exhaustive unit test coverage - a followup will update InstCombineCompares.cpp to use this.
Add a triple for powerpcle-*-*.
This is a little-endian encoding of the 32-bit PowerPC ABI, useful in certain niche situations:
1) A loader such as the FreeBSD loader which will be loading a little endian kernel. This is required for PowerPC64LE to load properly in pseries VMs.
Such a loader is implemented as a freestanding ELF32 LSB binary.
2) Userspace emulation of a 32-bit LE architecture such as x86 on 64-bit hosts such as PowerPC64LE with tools like box86 requires having a 32-bit LE toolchain and library set, as they operate by translating only the main binary and switching to native code when making library calls.
3) The Void Linux for PowerPC project is experimenting with running an entire powerpcle userland.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D93918
This introduces asm support for the Branch Record Buffer extension, through
the new 'brbe' subtarget feature. It consists of a new set of system registers
that enable the handling of branch records.
Patch written by Simon Tatham.
Reviewed By: ostannard
Differential Revision: https://reviews.llvm.org/D92389
This extends the command-line support for the 'armv8.7-a' architecture
name to the ARM target.
Based on a patch written by Momchil Velikov.
Reviewed By: ostannard
Differential Revision: https://reviews.llvm.org/D93231
This introduces command-line support for the 'armv8.7-a' architecture name
(and an alias without the '-', as usual), and for the 'ls64' extension name.
Based on patches written by Simon Tatham.
Reviewed By: ostannard
Differential Revision: https://reviews.llvm.org/D91776
Currently unknown keys when inputting mapping traits have the location set to the Value.
Example:
```
YAML:1:14: error: unknown key 'UnknownKey'
{UnknownKey: SomeValue}
^~~~~~~~~
```
This is unhelpful for a user as it draws them to fix the wrong item.
Reviewed By: silvas
Differential Revision: https://reviews.llvm.org/D93037
This is the first in a series of patches that attempts to migrate
existing cost instructions to return a new InstructionCost class
in place of a simple integer. This new class is intended to be
as light-weight and simple as possible, with a full range of
arithmetic and comparison operators that largely mirror the same
sets of operations on basic types, such as integers. The main
advantage to using an InstructionCost is that it can encode a
particular cost state in addition to a value. The initial
implementation only has two states - Normal and Invalid - but these
could be expanded over time if necessary. An invalid state can
be used to represent an unknown cost or an instruction that is
prohibitively expensive.
This patch adds the new class and changes the getInstructionCost
interface to return the new class. Other cost functions, such as
getUserCost, etc., will be migrated in future patches as I believe
this to be less disruptive. One benefit of this new class is that
it provides a way to unify many of the magic costs in the codebase
where the cost is set to a deliberately high number to prevent
optimisations taking place, e.g. vectorization. It also provides
a route to represent the extremely high, and unknown, cost of
scalarization of scalable vectors, which is not currently supported.
Differential Revision: https://reviews.llvm.org/D91174
Add an overload of `RedirectingFileSystem::create` that builds a
redirecting filesystem off of a simple vector of string pairs. This is
intended to be used to support `clang::arcmt::FileRemapper` and
`clang::PreprocessorOptions::RemappedFiles`.
Differential Revision: https://reviews.llvm.org/D91317
Uniformly return uniquely-owned filesystems from VFS creation APIs. The
one exception is `getRealFileSystem`, which has a single instance and
needs to be shared.
This is almost NFC, except that it fixes a memory leak in
`vfs::collectVFSFromYAML()`.
Depends on https://reviews.llvm.org/D92888
Differential Revision: https://reviews.llvm.org/D92890
Update all the users of `AlignedCharArrayUnion` to stop peeking inside
(to look at `buffer`) so that a follow-up patch can replace it with an
alias to `std::aligned_union_t`.
This was reviewed as part of https://reviews.llvm.org/D92512, but I'm
splitting this bit out to commit first to reduce churn in case the
change to `AlignedCharArrayUnion` needs to be reverted for some
unexpected reason.
Use a fast path for column width computation for ascii characters. Especially
relevant for llvm-objdump.
before:
% time ./bin/llvm-objdump -D -j .text /lib/libc.so.6 >/dev/null
./bin/llvm-objdump -D -j .text /lib/libc.so.6 > /dev/null 0.75s user 0.01s system 99% cpu 0.757 total
after:
% time ./bin/llvm-objdump -D -j .text /lib/libc.so.6 >/dev/null
./bin/llvm-objdump -D -j .text /lib/libc.so.6 > /dev/null 0.37s user 0.01s system 99% cpu 0.378 total
Differential Revision: https://reviews.llvm.org/D92180
This also teaches MachO writers/readers about the MachO cpu subtype,
beyond the minimal subtype reader support present at the moment.
This also defines a preprocessor macro to allow users to distinguish
__arm64__ from __arm64e__.
arm64e defaults to an "apple-a12" CPU, which supports v8.3a, allowing
pointer-authentication codegen.
It also currently defaults to ios14 and macos11.
Differential Revision: https://reviews.llvm.org/D87095
This implementation of `ELFDumper<ELFT>::printAttributes()` in llvm-readobj has issues:
1) It crashes when the content of the attribute section is empty.
2) It uses `unwrapOrError` and `reportWarning` calls, though
ideally we want to use `reportUniqueWarning`.
3) It contains a TODO about redundant format version check.
`lib/Support/ELFAttributeParser.cpp` uses a hardcoded constant instead of the named constant.
This patch fixes all these issues.
Differential revision: https://reviews.llvm.org/D92318
The static_assert in "libcxx/include/memory" was the main offender here,
but then I figured I might as well `git grep -i instantat` and fix all
the instances I found. One was in user-facing HTML documentation;
the rest were in comments or tests.
This retrieves CPU affinity via FreeBSD's cpuset(2) API, and makes LLVM
respect affinity settings configured by the user via the cpuset(1)
command.
In particular, this allows to reduce the number of threads used on
machines with high core counts, which can interact badly with
parallelized build systems. This is particularly noticable with lld,
which spawns lots of threads even for linking e.g. hello_world!
This fix is related to PR48193, but does not adress the more fundamental
problem, which is that LLVM by default grabs as many CPUs and/or threads
as possible.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D92271
I took the "Permitted"/"Not Permitted" combo from the `Tag_ARM_ISA_use` case (GNU tools print "Yes").
Reviewed By: compnerd, MaskRay, simon_tatham
Differential Revision: https://reviews.llvm.org/D90305
Truncates the APInt if the bit width is greater than the width specified,
otherwise do nothing
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D91445
In some places the parser guards against dereferencing `End`, while in
others it relies on the presence of a trailing `'\0'` to elide checks.
Add the remaining guards needed to ensure the parser never attempts to
dereference `End`, making it safe to not require a null-terminated input
buffer.
Update the parser fuzzer harness so that it tests with buffers that are
guaranteed to be non-null-terminated, null-terminated, and 1-terminated,
additionally ensuring the result of the parse is the same in each case.
Some of the regression tests were written by inspection, and some are
cases caught by the fuzzer which required additional fixes in the
parser.
Differential Revision: https://reviews.llvm.org/D84050
When we produce an YAML output, we also print leading zeroes currently.
An output might look like this:
```
- Name: .dynsym
Type: SHT_DYNSYM
Address: 0x0000000000001000
EntSize: 0x0000000000000018
```
There are probably no reason to print leading zeroes.
It just makes harder to read values. This patch stops printing them.
The output becomes like:
```
- Name: .dynsym
Type: SHT_DYNSYM
Address: 0x1000
EntSize: 0x18
```
This affects obj2yaml mostly, but also dsymutil and llvm-xray tools output.
Differential revision: https://reviews.llvm.org/D90930
Kazu Hirata