* Add inline to the helper functions because gcc-9 won't inline all of
them without the hint. I've avoided `__attribute__((always_inline))`
because gcc and clang will inline without it, and improves
compatibility.
* Replace the byte-by-byte copy in update() with endian::readbe32()
since perf reports that 1/2 of the time is spent copying into the
buffer before this patch.
When lld uses --build-id=sha1 it spends 30-45% of CPU in SHA1 depending on the binary (not wall-time since it is parallel). This patch speeds up SHA1 by a factor of 2 on clang-8 and 3 on gcc-6. This leads to a >10% improvement in overall linking time.
lld-speed-test benchmarks run on an Intel i9-9900k with Turbo disabled on CPU 0 compiled with clang-9. Stats recorded with `perf stat -r 5`. All inputs are using `--build-id=sha1`.
| Input | Before (seconds) | After (seconds) |
| --- | --- | --- |
| chrome | 2.14 | 1.82 (-15%) |
| chrome-icf | 2.56 | 2.29 (-10%) |
| clang | 0.65 | 0.53 (-18%) |
| clang-fsds | 0.69 | 0.58 (-16%) |
| clang-gdb-index | 21.71 | 19.3 (-11%) |
| gold | 0.42 | 0.34 (-19%) |
| gold-fsds | 0.431 | 0.355 (-17%) |
| linux-kernel | 0.625 | 0.575 (-8%) |
| llvm-as | 0.045 | 0.039 (-14%) |
| llvm-as-fsds | 0.035 | 0.039 (-11%) |
| mozilla | 11.3 | 9.8 (-13%) |
| mozilla-gc | 11.84 | 10.36 (-12%) |
| mozilla-O0 | 8.2 | 5.84 (-28%) |
| scylla | 5.59 | 4.52 (-19%) |
Reviewed By: ruiu, MaskRay
Differential Revision: https://reviews.llvm.org/D69295
Summary: The attached test case replicates a null dereference crash in
`yaml::Document::skip()`. This was fixed by adding a check and early
return in the method.
Reviewers: Bigcheese, hintonda, beanz
Reviewed By: hintonda
Subscribers: hiraditya, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69974
Summary:
The signed one is needed for implementation of `ConstantRange::smul_sat()`,
unsigned is for completeness only.
Reviewers: nikic, RKSimon, spatel
Reviewed By: nikic
Subscribers: hiraditya, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69993
Summary:
This patch adds PrintArgInline (after PrintArg) that strips the
leading spaces from an argument before printing them, for usage
inline.
Related bug: PR42943 <https://bugs.llvm.org/show_bug.cgi?id=42943>
Patch by Daan Sprenkels!
Reviewers: jhenderson, chandlerc, hintonda
Reviewed By: jhenderson
Subscribers: hiraditya, kristina, llvm-commits, dsprenkels
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69501
Summary: This patch fixes a number of bugs found in the YAML parser
through fuzzing. In general, this makes the parser more robust against
malformed inputs.
The fixes are mostly improved null checking and returning errors in
more cases. In some cases, asserts were changed to regular errors,
this provides the same robustness but also protects release builds
from the triggering conditions. This also improves the fuzzability of
the YAML parser since asserts can act as a roadblock to further
fuzzing once they're hit.
Each fix has a corresponding test case:
- TestAnchorMapError - Added proper null pointer handling in
`Stream::printError` if N is null and `KeyValueNode::getValue` if
getKey returns null, `Input::createHNodes` `dyn_casts` changed to
`dyn_cast_or_null` so the null pointer checks are actually able to
fail
- TestFlowSequenceTokenErrors - Added case in
`Document::parseBlockNode` for FlowMappingEnd, FlowSequenceEnd, or
FlowEntry tokens outside of mappings or sequences
- TestDirectiveMappingNoValue - Changed assert to regular error
return in `Scanner::scanValue`
- TestUnescapeInfiniteLoop - Fixed infinite loop in
`ScalarNode::unescapeDoubleQuoted` by returning an error for
unrecognized escape codes
- TestScannerUnexpectedCharacter - Changed asserts to regular error
returns in `Scanner::consume`
- TestUnknownDirective - For both of the inputs the stream doesn't
fail and correctly returns TK_Error, but there is no valid root
node for the document. There's no reasonable way to make the
scanner fail for unknown directives without breaking the YAML spec
(see spec-07-01.test). I think the assert is unnecessary given
that an error is still generated for this case.
The `SimpleKeys.clear()` line fixes a bug found by AddressSanitizer
triggered by multiple test cases - when TokenQueue is cleared
SimpleKeys is still holding dangling pointers into it, so SimpleKeys
should be cleared as well.
Patch by Thomas Finch!
Reviewers: chandlerc, Bigcheese, hintonda
Reviewed By: Bigcheese, hintonda
Subscribers: hintonda, kristina, beanz, dexonsmith, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61608
Summary: Currently there is no implementation of `sys::getHostCPUName()` for Darwin ARM targets. This patch makes it so that LLVM running on ARM makes reasonable guesses about the CPU features of the host CPU.
Reviewers: t.p.northover, lhames, efriedma
Reviewed By: efriedma
Subscribers: rjmccall, efriedma, kristof.beyls, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69597
This class was a bit overengineered, and was triggering some PVS warnings.
Instead, put strings into a NameType and let clients unconditionally treat it
as a Node.
Use `/proc/self/exe` to get the current executable
path on GNU Hurd.
Patch by sthibaul (Samuel Thibault)
Differential Revision: https://reviews.llvm.org/D69683
Summary:
Add a flag `F_no_mmap` to `FileOutputBuffer` to support
`--[no-]mmap-output-file` in ELF LLD. LLD currently explicitly ignores
this flag for compatibility with GNU ld and gold.
We need this flag to speed up link time for large binaries in certain
scenarios. When we link some of our larger binaries we find that LLD
takes 50+ GB of memory, which causes memory pressure. The memory
pressure causes the VM to flush dirty pages of the output file to disk.
This is normally okay, since we should be flushing cold pages. However,
when using BtrFS with compression we need to write 128KB at a time when
we flush a page. If any page in that 128KB block is written again, then
it must be flushed a second time, and so on. Since LLD doesn't write
sequentially this causes write amplification. The same 128KB block will
end up being flushed multiple times, causing the linker to many times
more IO than necessary. We've observed 3-5x faster builds with
-no-mmap-output-file when we hit this scenario.
The bad scenario only applies to compressed filesystems, which group
together multiple pages into a single compressed block. I've tested
BtrFS, but the problem will be present for any compressed filesystem
on Linux, since it is caused by the VM.
Silently ignoring --no-mmap-output-file caused a silent regression when
we switched from gold to lld. We pass --no-mmap-output-file to fix this
edge case, but since lld silently ignored the flag we didn't realize it
wasn't being respected.
Benchmark building a 9 GB binary that exposes this edge case. I linked 3
times with --mmap-output-file and 3 times with --no-mmap-output-file and
took the average. The machine has 24 cores @ 2.4 GHz, 112 GB of RAM,
BtrFS mounted with -compress-force=zstd, and an 80% full disk.
| Mode | Time |
|---------|-------|
| mmap | 894 s |
| no mmap | 126 s |
When compression is disabled, BtrFS performs just as well with and
without mmap on this benchmark.
I was unable to reproduce the regression with any binaries in
lld-speed-test.
Reviewed By: ruiu, MaskRay
Differential Revision: https://reviews.llvm.org/D69294
Summary:
Compare two values, and if they are different, return the position of the
most significant bit that is different in the values.
Needed for D69387.
Reviewers: nikic, spatel, sanjoy, RKSimon
Reviewed By: nikic
Subscribers: xbolva00, hiraditya, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69439
Summary:
There are `*_ov()` functions already, so at least for consistency it may be good to also have saturating variants.
These may or may not be needed for `ConstantRange`'s `shlWithNoWrap()`
Reviewers: spatel, nikic
Reviewed By: nikic
Subscribers: hiraditya, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69398
Summary:
There are `*_ov()` functions already, so at least for consistency it may be good to also have saturating variants.
These may or may not be needed for `ConstantRange`'s `mulWithNoWrap()`
Reviewers: spatel, nikic
Reviewed By: nikic
Subscribers: hiraditya, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69397
This reverts commit 32ce14e55e.
In post-commit review, Pavel pointed out that there's a simpler way to
ignore SIGPIPE in lldb that doesn't rely on llvm's handlers.
This roughly mimics `std::thread(...).detach()` except it allows to
customize the stack size. Required for https://reviews.llvm.org/D50993.
I've decided against reusing the existing `llvm_execute_on_thread` because
it's not obvious what to do with the ownership of the passed
function/arguments:
1. If we pass possibly owning functions data to `llvm_execute_on_thread`,
we'll lose the ability to pass small non-owning non-allocating functions
for the joining case (as it's used now). Is it important enough?
2. If we use the non-owning interface in the new use case, we'll force
clients to transfer ownership to the spawned thread manually, but
similar code would still have to exist inside
`llvm_execute_on_thread(_async)` anyway (as we can't just pass the same
non-owning pointer to pthreads and Windows implementations, and would be
forced to wrap it in some structure, and deal with its ownership.
Patch by Dmitry Kozhevnikov!
Differential Revision: https://reviews.llvm.org/D51103
Works on this dependency chain:
ArrayRef.h ->
Hashing.h -> --CUT--
Host.h ->
StringMap.h / StringRef.h
ArrayRef is very popular, but Host.h is rarely needed. Move the
IsBigEndianHost constant to SwapByteOrder.h. Clients of that header are
more likely to need it.
llvm-svn: 375316
Occasionally, during test teardown, LLDB writes to a closed pipe.
Sometimes the communication is inherently unreliable, so LLDB tries to
avoid being killed due to SIGPIPE (it calls `signal(SIGPIPE, SIG_IGN)`).
However, LLVM's default SIGPIPE behavior overrides LLDB's, causing it to
exit with IO_ERR.
Opt LLDB out of the default SIGPIPE behavior. I expect that this will
resolve some LLDB test suite flakiness (tests randomly failing with
IO_ERR) that we've seen since r344372.
rdar://55750240
Differential Revision: https://reviews.llvm.org/D69148
llvm-svn: 375288
Reland r375051 (reverted in r375052) after fixing lld tests on Windows in r375126 and r375131.
Original description: Update GlobPattern in libSupport to handle a few more cases. It does not fully match the `fnmatch` used by GNU objcopy since named character classes (e.g. `[[:digit:]]`) are not supported, but this should support most existing use cases (mostly just `*` is what's used anyway).
This will be used to implement the `--wildcard` flag in llvm-objcopy to be more compatible with GNU objcopy.
This is split off of D66613 to land the libSupport changes separately. The llvm-objcopy part will land soon.
Reviewers: jhenderson, MaskRay, evgeny777, espindola, alexshap
Reviewed By: MaskRay
Subscribers: nickdesaulniers, emaste, arichardson, hiraditya, jakehehrlich, abrachet, seiya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66613
llvm-svn: 375149
This reverts r375051 (git commit a409afaad6)
The patch does not work on Windows due to `\` in filenames being interpreted as escaping rather than literal path separators when used by lld linker scripts.
llvm-svn: 375052
Summary: Update GlobPattern in libSupport to handle a few more cases. It does not fully match the `fnmatch` used by GNU objcopy since named character classes (e.g. `[[:digit:]]`) are not supported, but this should support most existing use cases (mostly just `*` is what's used anyway).
This will be used to implement the `--wildcard` flag in llvm-objcopy to be more compatible with GNU objcopy.
This is split off of D66613 to land the libSupport changes separately. The llvm-objcopy part will land soon.
Reviewers: jhenderson, MaskRay, evgeny777, espindola, alexshap
Reviewed By: MaskRay
Subscribers: nickdesaulniers, emaste, arichardson, hiraditya, jakehehrlich, abrachet, seiya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66613
undo objcopy changes to make this libsupport only
llvm-svn: 375051
Before this patch, changing the working directory of the RedirectingFS
would just forward to its external file system. This prevented us from
having a working directory that only existed in the VFS mapping.
This patch adds support for a virtual working directory in the
RedirectingFileSystem. It now keeps track of its own WD in addition to
updating the WD of the external file system. This ensures that we can
still fall through for relative paths.
This change was originally motivated by the reproducer infrastructure in
LLDB where we want to deal transparently with relative paths.
Differential revision: https://reviews.llvm.org/D65677
llvm-svn: 374955
This reverts the original commit and the follow up:
Revert "[VirtualFileSystem] Support virtual working directory in the RedirectingFS"
Revert "[test] Update YAML mapping in VirtualFileSystemTest"
llvm-svn: 374935
Before this patch, changing the working directory of the RedirectingFS
would just forward to its external file system. This prevented us from
having a working directory that only existed in the VFS mapping.
This patch adds support for a virtual working directory in the
RedirectingFileSystem. It now keeps track of its own WD in addition to
updating the WD of the external file system. This ensures that we can
still fall through for relative paths.
This change was originally motivated by the reproducer infrastructure in
LLDB where we want to deal transparently with relative paths.
Differential revision: https://reviews.llvm.org/D65677
llvm-svn: 374917
The FileCheck utility is enhanced to support a `--ignore-case`
option. This is useful in cases where the output of Unix tools
differs in case (e.g. case not specified by Posix).
Reviewers: Bigcheese, jakehehrlich, rupprecht, espindola, alexshap, jhenderson, MaskRay
Differential Revision: https://reviews.llvm.org/D68146
llvm-svn: 374538
The intended usage is to measure relatively expensive operations. So the
cost of the statistic is negligible compared to the cost of a measured
operation and can be enabled all the time without impairing the
compilation time.
rdar://problem/55715134
Reviewers: dsanders, bogner, rtereshin
Reviewed By: dsanders
Subscribers: hiraditya, jkorous, dexonsmith, ributzka, cfe-commits, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68252
llvm-svn: 374490
r179397 added Parallel.h and implemented it terms of concrt in 2013.
In 2015, a cross-platform implementation of the functions has appeared
and is in use everywhere but on Windows (r232419). r246219 hints that
<thread> had issues in MSVC2013, but r296906 suggests they've been fixed
now that we require 2015+.
So remove the concrt code. It's less code, and it sounds like concrt has
conceptual and performance issues, see PR41198.
I built blink_core.dll in a debug component build with full symbols and
in a release component build without any symbols. I couldn't measure a
performance difference for linking blink_core.dll before and after this
patch.
Differential Revision: https://reviews.llvm.org/D68820
llvm-svn: 374421
This improves readability of Windows path string literals in LLVM IR.
The LLVM assembler has supported \\ in IR strings for a long time, but
the lexer doesn't tolerate escaped quotes, so they have to be printed as
\22 for now.
llvm-svn: 374415
Reid Kleckner