As discussed in https://reviews.llvm.org/D68549, the actual issue
here seems to be that the BumpPtrAllocator is growing far too slow
because of the 256 different StringPools used as the backend for ConstString.
At the same time the original patch made ConstString allocate memory in
256MiB slabs for the same reason, meaning that the RSS usage of LLDB increased
by a few hundred MiB for all users without bringing any noticeable speedup
for most of them.
llvm-svn: 375062
BumpPtrAllocator allocates in 4KiB chunks, which with any larger
project is going to result in a large number of allocations.
Increasing allocation size this way can save 10%-20% of symbol
load time for a huge C++ project with correctly built debuginfo.
Differential Revision: https://reviews.llvm.org/D68549
llvm-svn: 374583
There is an alternative method to GetConstCStringWithLength that
takes a StringRef. GetConstCStringWithLength also calls this
method in the end, so directly calling the StringRef saves
us from a unnecessary conversion to a C-string.
llvm-svn: 358357
A lot of comments in LLDB are surrounded by an ASCII line to delimit the
begging and end of the comment.
Its use is not really consistent across the code base, sometimes the
lines are longer, sometimes they are shorter and sometimes they are
omitted. Furthermore, it looks kind of weird with the 80 column limit,
where the comment actually extends past the line, but not by much.
Furthermore, when /// is used for Doxygen comments, it looks
particularly odd. And when // is used, it incorrectly gives the
impression that it's actually a Doxygen comment.
I assume these lines were added to improve distinguishing between
comments and code. However, given that todays editors and IDEs do a
great job at highlighting comments, I think it's worth to drop this for
the sake of consistency. The alternative is fixing all the
inconsistencies, which would create a lot more churn.
Differential revision: https://reviews.llvm.org/D60508
llvm-svn: 358135
My apologies for the large patch. With the exception of ConstString.h
itself it was entirely produced by sed.
ConstString has exactly one const char * data member, so passing a
ConstString by reference is not any more efficient than copying it by
value. In both cases a single pointer is passed. But passing it by
value makes it harder to accidentally return the address of a local
object.
(This fixes rdar://problem/48640859 for the Apple folks)
Differential Revision: https://reviews.llvm.org/D59030
llvm-svn: 355553
LLDB testsuite fails when built by GCC8 on:
LLDB :: SymbolFile/DWARF/find-basic-namespace.cpp
This is because this code in LLDB codebase has undefined behavior:
#include <algorithm>
#include <string.h>
// lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp:1731
static struct section_64 {
char sectname[16];
char segname[16];
} sect64 = { {'_','_','a','p','p','l','e','_','n','a','m','e','s','p','a','c'}, "__DWARF" };
int main() {
return std::min<size_t>(strlen(sect64.sectname), sizeof(sect64.sectname));
}
It has been discussed as a (false) bugreport to GCC:
wrong-code: LLDB testcase fails: SymbolFile/DWARF/find-basic-namespace.cpp
https://bugzilla.redhat.com/show_bug.cgi?id=1672436
Differential Revision: https://reviews.llvm.org/D57781
llvm-svn: 353280
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
This patch removes the comments following the header includes. They were
added after running IWYU over the LLDB codebase. However they add little
value, are often outdates and burdensome to maintain.
Differential revision: https://reviews.llvm.org/D54385
llvm-svn: 346625
Summary:
This issue came up because it caused problems in our unit tests. The StringPool did connect counterparts only once and silently ignored the values passed in subsequent calls.
The simplest solution for the unit tests would be silent overwrite. In practice, however, it seems useful to assert that we never overwrite a different mangled counterpart.
If we ever have mangled counterparts for other languages than C++, this makes it more likely to notice collisions.
I added an assertion that allows the following cases:
* inserting a new value
* overwriting the empty string
* overwriting with an identical value
I fixed the unit tests, which used "random" strings and thus produced collisions.
It would be even better if there was a way to reset or isolate the StringPool, but that's a different story.
Reviewers: jingham, friss, labath
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D50536
llvm-svn: 339669
This is intended as a clean up after the big clang-format commit
(r280751), which unfortunately resulted in many of the comment
paragraphs in LLDB being very hard to read.
FYI, the script I used was:
import textwrap
import commands
import os
import sys
import re
tmp = "%s.tmp"%sys.argv[1]
out = open(tmp, "w+")
with open(sys.argv[1], "r") as f:
header = ""
text = ""
comment = re.compile(r'^( *//) ([^ ].*)$')
special = re.compile(r'^((([A-Z]+[: ])|([0-9]+ )).*)|(.*;)$')
for line in f:
match = comment.match(line)
if match and not special.match(match.group(2)):
# skip intentionally short comments.
if not text and len(match.group(2)) < 40:
out.write(line)
continue
if text:
text += " " + match.group(2)
else:
header = match.group(1)
text = match.group(2)
continue
if text:
filled = textwrap.wrap(text, width=(78-len(header)),
break_long_words=False)
for l in filled:
out.write(header+" "+l+'\n')
text = ""
out.write(line)
os.rename(tmp, sys.argv[1])
Differential Revision: https://reviews.llvm.org/D46144
llvm-svn: 331197
This patch removes the HashString function from StringExtraces and
replaces its uses with calls to djbHash from DJB.h.
This change is *almost* NFC. While the algorithm is identical, the
djbHash implementation in StringExtras used 0 as its default seed while
the implementation in DJB uses 5381. The latter has been shown to result
in less collisions and improved avalanching and is used by the DWARF
accelerator tables.
Because some test were implicitly relying on the hash order, I've
reverted to using zero as a seed for the following two files:
lld/include/lld/Core/SymbolTable.h
llvm/lib/Support/StringMap.cpp
Differential revision: https://reviews.llvm.org/D43615
llvm-svn: 326091
It looks like some of our tests depend on the ordering of hashed values.
I'm reverting my changes while I try to reproduce and fix this locally.
Failing builds:
lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/18388
lab.llvm.org:8011/builders/clang-cmake-x86_64-sde-avx512-linux/builds/6743
lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast/builds/15607
llvm-svn: 326082
This removes the HashString function from StringExtraces and replaces
its uses with calls to djbHash from DJB.h
This is *almost* NFC. While the algorithm is identical, the djbHash
implementation in StringExtras used 0 as its seed while the
implementation in DJB uses 5381. The latter has been shown to result in
less collisions and improved avalanching.
https://reviews.llvm.org/D43615
(cherry picked from commit 77f7f965bc9499a9ae768a296ca5a1f7347d1d2c)
llvm-svn: 326081
Summary: ConstStrings are immutable, so there is no need to grab even a reader lock in order to read the length field.
Reviewers: #lldb, labath
Reviewed By: labath
Subscribers: zturner, labath, lldb-commits
Differential Revision: https://reviews.llvm.org/D32306
Patch by Scott Smith <scott.smith@purestorage.com>
llvm-svn: 301642
This patch makes adjustments to header file includes in
lldbUtility based on recommendations by the iwyu tool
(include-what-you-use). The goal here is to make sure that
all files include the exact set of headers which are needed
for that file only, to eliminate cases of dead includes (e.g.
someone deleted some code but forgot to delete the header
includes that that code necessitated), and to eliminate the
case where header includes are picked up transitively.
llvm-svn: 299676
Summary:
The std::call_once implementation in libstdc++ has problems on few systems: NetBSD, OpenBSD and Linux PPC. LLVM ships with a homegrown implementation llvm::call_once to help on these platforms.
This change is required in the NetBSD LLDB port. std::call_once with libstdc++ results with crashing the debugger.
Sponsored by <The NetBSD Foundation>
Reviewers: labath, joerg, emaste, mehdi_amini, clayborg
Reviewed By: labath, clayborg
Subscribers: #lldb
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D29288
llvm-svn: 294202
Summary:
Per discussion in D28616, having two ways two request logging (log
enable lldb XXX verbose && log enable -v lldb XXX) is confusing. This
removes the first option and standardizes all code to use the second
one.
I've added a LLDB_LOGV macro as a shorthand for if(log &&
log->GetVerbose()) and switched most of the affected log statements to
use that (I've only left a couple of cases that were doing complex
computations in an if(log) block).
Reviewers: jingham, zturner
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D29510
llvm-svn: 294113
This moves the following classes from Core -> Utility.
ConstString
Error
RegularExpression
Stream
StreamString
The goal here is to get lldbUtility into a state where it has
no dependendencies except on itself and LLVM, so it can be the
starting point at which to start untangling LLDB's dependencies.
These are all low level and very widely used classes, and
previously lldbUtility had dependencies up to lldbCore in order
to use these classes. So moving then down to lldbUtility makes
sense from both the short term and long term perspective in
solving this problem.
Differential Revision: https://reviews.llvm.org/D29427
llvm-svn: 293941