I am using it in https://reviews.llvm.org/D69399.
This change changes how obj2yaml dumps arrays of `llvm::yaml::Hex8/llvm::yaml::Hex16/llvm::yaml::Hex32`
from:
```
PayloadBytes:
- 0x01
- 0x02
...
```
To
```
PayloadBytes: [ 0x01, 0x02, ... ]
```
The latter way is shorter and looks better for arrays.
Differential revision: https://reviews.llvm.org/D69558
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
This reverts commit 32ce14e55e5a99dd99c3b4fd4bd0ccaaf2948c30.
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 reverts commit 40668abca4d307e02b33345cfdb7271549ff48d0.
This causes clang tests to fail, as stacksize=0 is being explicitly passed and
is no longer a no-op.
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
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
Summary:
The current implementation eats the current errors and just outputs
the message parameter passed to llvm::cantFail. This change appends
the original error message(s), so the user can see exactly why
cantFail failed. New logic is conditional on NDEBUG.
Reviewed By: lhames
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69057
llvm-svn: 375176
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 a409afaad64ce83ea44cc30ee5f96b6e613a6e98)
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
David added the JamCRC implementation in r246590. More recently, Eugene
added a CRC-32 implementation in r357901, which falls back to zlib's
crc32 function if present.
These checksums are essentially the same, so having multiple
implementations seems unnecessary. This replaces the CRC-32
implementation with the simpler one from JamCRC, and implements the
JamCRC interface in terms of CRC-32 since this means it can use zlib's
implementation when available, saving a few bytes and potentially making
it faster.
JamCRC took an ArrayRef<char> argument, and CRC-32 took a StringRef.
This patch changes it to ArrayRef<uint8_t> which I think is the best
choice, and simplifies a few of the callers nicely.
Differential revision: https://reviews.llvm.org/D68570
llvm-svn: 374148
Summary:
Fix initialization style of objects allocated on the stack and member
objects in unit test to use the "Type Var(init list)" and
"Type Member{init list}" convention. The latter fixes the buildbot
breakage.
Reviewers: jhenderson, probinson, arichardson, grimar, jdenny
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68425
llvm-svn: 373755
Summary:
Fix initialization style of objects allocated on the stack in unit test
to use the "Type Var(init list)" convention.
Reviewers: jhenderson, probinson, arichardson, grimar, jdenny
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68425
llvm-svn: 373717
Summary:
Most of the class definition in llvm/include/llvm/Support/FileCheck.h
are actually implementation details that should not be relied upon. This
commit moves all of it in a new header file under
llvm/lib/Support/FileCheck. It also takes advantage of the code movement
to put the code into a new llvm::filecheck namespace.
Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk
Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar, arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67649
llvm-svn: 373395
Summary:
Commit r366897 introduced the possibility to set a variable from an
expression, such as [[#VAR2:VAR1+3]]. While introducing this feature, it
introduced extra logic to allow using such a variable on the same line
later on. Unfortunately that extra logic is flawed as it relies on a
mapping from variable to expression defining it when the mapping is from
variable definition to expression. This flaw causes among other issues
PR42896.
This commit avoids the problem by forbidding all use of a variable
defined on the same line, and removes the now useless logic. Redesign
will be done in a later commit because it will require some amount of
refactoring first for the solution to be clean. One example is the need
for some sort of transaction mechanism to set a variable temporarily and
from an expression and rollback if the CHECK pattern does not match so
that diagnostics show the right variable values.
Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk
Subscribers: JonChesterfield, rogfer01, hfinkel, kristina, rnk, tra, arichardson, grimar, dblaikie, probinson, llvm-commits, hiraditya
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66141
llvm-svn: 370663
Summary:
This is motivated by D63591, where we realized that there isn't a really
good way of telling whether a DataExtractor is reading actual data, or
is it just returning default values because it reached the end of the
buffer.
This patch resolves that by providing a new "Cursor" class. A Cursor
object encapsulates two things:
- the current position/offset in the DataExtractor
- an error object
Storing the error object inside the Cursor enables one to use the same
pattern as the std::{io}stream API, where one can blindly perform a
sequence of reads and only check for errors once at the end of the
operation. Similarly to the stream API, as soon as we encounter one
error, all of the subsequent operations are skipped (return default
values) too, even if the would suceed with clear error state. Unlike the
std::stream API (but in line with other llvm APIs), we force the error
state to be checked through usage of llvm::Error.
Reviewers: probinson, dblaikie, JDevlieghere, aprantl, echristo
Subscribers: kristina, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63713
llvm-svn: 370042
Summary:
There was a subtle, but pretty important difference between the Slice
and regular versions of this function. The Slice function was
zero-initializing the rest of the buffer when the read syscall returned
less bytes than expected, while the regular function did not.
This patch removes the inconsistency by making both functions *not*
zero-initialize the buffer. The zeroing code is moved to the
MemoryBuffer class, which is currently the only user of this code. This
makes the API more consistent, and the code shorter.
While in there, I also refactor the functions to return the number of
bytes through the regular return value (via Expected<size_t>) instead of
a separate by-ref argument.
Reviewers: aganea, rnk
Subscribers: kristina, Bigcheese, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66471
llvm-svn: 369627
This recommits r368977, which was reverted in r369027 due to test
failures in lldb. The cause of this was different behavior of
readNativeFileSlice on windows and unix. These have been addressed in
r369269.
The original commit message was:
In case the function was called with a desired read size *and* the file
was not an "mmap()" candidate, the function was falling back to a
"pread()", but it was failing to check the result of that system call.
This meant that the function would return "success" even though the read
operation failed, and it returned a buffer full of uninitialized memory.
Reviewers: rnk, dblaikie
Subscribers: kristina, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66224
llvm-svn: 369370
Summary:
The windows version implementation of readNativeFileSlice, was trying to
match the POSIX behavior of not treating EOF as an error, but it was
only handling the case of reading from a pipe. Attempting to read past
the end of a regular file returns a slightly different error code, which
needs to be handled too. This patch adds ERROR_HANDLE_EOF to the list of
error codes to be treated as an end of file, and adds some unit tests
for the API.
This issue was found while attempting to land D66224, which caused a bunch of
lldb tests to start failing on windows.
Reviewers: rnk, aganea
Subscribers: kristina, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66344
llvm-svn: 369269
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.
llvm-svn: 369013
Summary:
In case the function was called with a desired read size *and* the file
was not an "mmap()" candidate, the function was falling back to a
"pread()", but it was failing to check the result of that system call.
This meant that the function would return "success" even though the read
operation failed, and it returned a buffer full of uninitialized memory.
Reviewers: rnk, dblaikie
Subscribers: kristina, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D66224
llvm-svn: 368977
This reverts commit r368849, because it breaks some bots (e.g.
llvm-clang-x86_64-win-fast).
It turns out this is not as NFC as we had hoped, because operator== will
consider two std::error_codes to be distinct even though they both hold
"success" values if they have different categories.
llvm-svn: 368854
Summary:
The main motivation for this is unit tests, which contain a large macro
for pretty-printing std::error_code, and this macro is duplicated in
every file that needs to do this. However, the functionality may be
useful elsewhere too.
In this patch I have reimplemented the existing ASSERT_NO_ERROR macros
to reuse the new functionality, but I have kept the macro (as a
one-liner) as it is slightly more readable than ASSERT_EQ(...,
std::error_code()).
Reviewers: sammccall, ilya-biryukov
Subscribers: zturner, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65643
llvm-svn: 368849
This fixes a bug for making path with a //net style root absolute. I
discovered the bug while writing a test case for the VFS, which uses
these paths because they're both legal absolute paths on Windows and
Unix.
Differential revision: https://reviews.llvm.org/D65675
llvm-svn: 368053
This updates all libraries and tools in LLVM Core to use 64-bit offsets
which directly or indirectly come to DataExtractor.
Differential Revision: https://reviews.llvm.org/D65638
llvm-svn: 368014
Using 64-bit offsets is required to fully implement 64-bit DWARF.
As these classes are used in many different libraries they should
temporarily support both 32- and 64-bit offsets.
Differential Revision: https://reviews.llvm.org/D64006
llvm-svn: 368013
Added AddOverflow, SubOverflow and MulOverflow to compute truncated results and return a flag indicating whether overflow occured.
Differential Revision: https://reviews.llvm.org/D65494
llvm-svn: 367470
