| Commit message (Collapse) | Author | Age | Files | Lines |
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D62502 had a bug (visible only with D62503 reverted), where it would
error out if attempting to read a string from memory and the memory page
after the string happened to be unmapped.
This fixes the problem by checking for whether ReadMemory read *any*
bytes, instead of checking whether it returned an error. A greater
question is whether ReadMemory should even return an error if it read at
least one byte, but I'm leaving that for a separate patch.
llvm-svn: 364748
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operator new doesn't return a null pointer, even if one turns off
exceptions (it calls std::terminate instead). Therefore, all of this is
dead code.
llvm-svn: 364744
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Reverting this again as it doesn't appear to solve the flakiness on the
LLDB standalone bot.
llvm-svn: 364722
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llvm-svn: 364702
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MachO only for this patch.
Differential Revision: https://reviews.llvm.org/D63914
<rdar://problem/51463642>
llvm-svn: 364686
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The arbitrary timeout when flushing GDB remote packets caused
non-determinism and flakiness between test runs. I suspect it is what's
causing the flakiness of the reproducer tests on GreenDragon, and want
to see if removing it causes that to go away.
This change was originally introduced in r197579 to discard a
`$T02thread:01;#4` that QEMU was sending. If anybody knows how to test
that this continues working after removing this code, I'd love to hear
it.
llvm-svn: 364669
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on a thread. When talking to some older gdb-remote stubs, We were getting
a stop reason from the stop reply packet and setting it on the relevant
thread before we updated the full stop list. That would get discarded when
the full list was updated.
Also, if you already have a thread list when you go to see if there is an
Operating System plugin, and you do indeed load a new OS plugin, you have to
re-fetch the thread list or it will only show the raw threads.
Differential Revision: https://reviews.llvm.org/D62887
llvm-svn: 364666
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llvm-svn: 364614
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Reenable SysV x86_64 ABI usage on NetBSD that was accidentally removed
in r364216. This fixes numerous test failures with messages similar
to the following:
error: Can't run the expression locally: Interpreter doesn't handle
one of the expression's opcodes
llvm-svn: 364503
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This fixes two replay issues that caused the tests to behave
erratically:
1. It fixes an off-by-one error, where all replies where shifted by 1
because of a `+` packet that should've been ignored.
2. It fixes another off-by-one-error, where an asynchronous ^C was
offsetting all subsequent packets. The reason is that we
'synchronize' requests and replies. In reality, a stop reply is only
sent when the process halt. During replay however, we instantly
report the stop, as the reply to packets like continue (vCont).
Both packets should be ignored, and indeed, checking the gdb-remote log,
no unexpected packets are received anymore.
Additionally, be more pedantic when it comes to unexpected packets and
return an failure form the replay server. This way we should be able to
catch these things faster in the future.
llvm-svn: 364494
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The qemu x86_64 target returns a target.xml register definition file which
includes other xml files and they include others, etc. Also, the registers
are not put in register groups like lldb wants to see.
This patch (1) puts registers that aren't in a register group in a "general"
register group, (2) change ProcessGDBRemote::GetGDBServerRegisterInfo to
be a method that starts the parsing, asking a recurisve function to fetch
and parse target.xml, (3) adds
ProcessGDBRemote::GetGDBServerRegisterInfoXMLAndProcess which can recusively
call itself to read and parse included xml files, (4) in addition to expecting
the top-level <target> element (which only happens in the top level xml file),
also an xml file that consists of a <feature> node - read the register
defintions and includes from that <feature> element.
<rdar://problem/49537922>
Differential revision: https://reviews.llvm.org/D63802
llvm-svn: 364484
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This reverts commit a7335393f50246b59db450dc6005f7c8f29e73a6.
It seems this is breaking a bunch of tests (https://reviews.llvm.org/D62503#1549874) so reverting until I find the time to repro and fix.
llvm-svn: 364355
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Summary:
With the last round of refactors, supporting type units in dwo files
becomes almost trivial. This patch contains a couple of small fixes,
which taken as a whole make type units work in the split dwarf scenario
(both DWARF4 and DWARF5):
- DWARFContext: make sure we actually read the debug_types.dwo section
- DWARFUnit: set string offsets base on all units in the dwo file, not
just the main CU
- ManualDWARFIndex: index all units in the file
- SymbolFileDWARFDwo: Search for the single compile unit in the file, as
we can no longer assume it will be the first one
The last part makes it obvious that there is still some work to be done
here, namely that we do not support dwo files with multiple compile
units. That is something that should be easier after the DIERef
refactors, but it still requires more work.
Tests are added for the type units+split dwarf + dwarf4/5 scenarios, as
well as a test that checks we behave reasonably in the presence of dwo
files with multiple CUs.
Reviewers: clayborg, JDevlieghere, aprantl
Subscribers: arphaman, lldb-commits
Differential Revision: https://reviews.llvm.org/D63643
llvm-svn: 364274
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llvm-svn: 364223
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Summary:
Implement the ABI for WIndows-x86_64 including register info and calling convention.
Handled nested struct returned in register (SysV doesn't have it supported)
Reviewers: xiaobai, compnerd
Reviewed By: compnerd
Subscribers: labath, jasonmolenda, fedor.sergeev, mgorny, teemperor, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D62213
llvm-svn: 364216
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Summary:
This change extracts functionalities from processwindows into a
introduced processdebugger that can be reused in native process
debugging.
The main reason is that the native process debugging
can't directly be based on processwindows or be implemented
as a pass-through to this plugin since the plugin has ties to
Target and Process classes that are needed in host debugging but
not necessary in native debugging.
Reviewers: labath, Hui, jfb, clayborg, amccarth
Reviewed By: labath
Subscribers: amccarth, dexonsmith, mgorny, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D63166
llvm-svn: 364210
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Summary:
ObjCLanguageRuntime was being pulled into LanguageRuntime because of
Breakpoint Preconditions. If we move BreakpointPrecondition out of Breakpoint,
we can extend the LanguageRuntime plugin interface so that LanguageRuntimes
can give us a BreakpointPrecondition for exceptions.
Differential Revision: https://reviews.llvm.org/D63181
llvm-svn: 364098
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Introduce two common helpers to take care of splitting and recombining
YMM registers to/from XSAVE-like data. Since FreeBSD, Linux and NetBSD
all use XSAVE-like data structures but with potentially different field
layouts, the function takes two pointers -- to XMM register and to YMM
high bits, and copies the data from/to YMMReg type.
While at it, remove support for big endian. To mine and Pavel Labath's
combined knowledge, there is no such thing on x86. Furthermore,
assuming that the YMM register data would be swapped for big endian
seems to be a weird assumption.
Differential Revision: https://reviews.llvm.org/D63610
llvm-svn: 364042
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Summary:
When dwo support was introduced, it used a trick where debug info
entries were referenced by the offset of the compile unit in the main
file, but the die offset was relative to the dwo file. Although there
was some elegance to it, this representation was starting to reach its
breaking point:
- the fact that the skeleton compile unit owned the DWO file meant that
it was impossible (or at least hard and unintuitive) to support DWO
files containing more than one compile unit. These kinds of files are
produced by LTO for example.
- it made it impossible to reference any DIEs in the skeleton compile
unit (although the skeleton units are generally empty, clang still
puts some info into them with -fsplit-dwarf-inlining).
- (current motivation) it made it very hard to support type units placed
in DWO files, as type units don't have any skeleton units which could
be referenced in the main file
This patch addresses this problem by introducing an new
"dwo_num" field to the DIERef class, whose purpose is to identify the
dwo file. It's kind of similar to the dwo_id field in DWARF5 unit
headers, but while this is a 64bit hash whose main purpose is to catch
file mismatches, this is just a smaller integer used to indentify a
loaded dwo file. Currently, this is based on the index of the skeleton
compile unit which owns the dwo file, but it is intended to be
eventually independent of that (to support the LTO use case).
Simultaneously the cu_offset is dropped to conserve space, as it is no
longer necessary. This means we can remove the "BaseObjectOffset" field
from the DWARFUnit class. It also means we can remove some of the
workarounds put in place to support the skeleton-unit+dwo-die combo.
More work is needed to remove all of them, which is out of scope of this
patch.
Reviewers: JDevlieghere, clayborg, aprantl
Subscribers: mehdi_amini, dexonsmith, arphaman, lldb-commits
Differential Revision: https://reviews.llvm.org/D63428
llvm-svn: 364009
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Remove most of the abstraction over ptrace() register operations,
as it has little value and introduces more code than it saves.
Instead, leave a single ptrace() wrapper method and call it directly
from ReadRegisterSet() and WriteRegisterSet() with correct PT_* request
and buffer.
Remove the remaining direct ReadGPR() and WriteGPR() invocations
with ReadRegisterSet() and WriteRegisterSet().
Cleanup suggested by Pavel Labath in D63545.
Differential Revision: https://reviews.llvm.org/D63594
llvm-svn: 363923
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That commit changed DIERef from a struct to a class, but did not update
the forward-declarations. This fixes one forward-declaration, and
removes other (unused) decls.
llvm-svn: 363915
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Summary:
Instead of accessing the fields directly, use accessor functions to
provide access to the DIERef components. This allows us to decouple the
external interface, from the internal representation. The external
interface can use llvm::Optional and similar goodies, while the data can
still be stored internally in a more compact representation.
I also document the purpose of the existing DIERef fields.
The main motivation for this change is a need to introduce an additional
field to the DIERef class, but I believe the change has its own merit.
Reviewers: JDevlieghere, aprantl, clayborg
Subscribers: arphaman, lldb-commits
Differential Revision: https://reviews.llvm.org/D63400
llvm-svn: 363910
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Summary:
These fields are unused and have been since their inception, from what
I can tell.
Reviewers: compnerd, JDevlieghere, davide, labath
Subscribers: kubamracek, lldb-commits
Differential Revision: https://reviews.llvm.org/D63357
llvm-svn: 363881
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llvm-svn: 363827
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Remove the checks for FPU presence, FXSAVE support and usage from
the code for x86_64. Those are always true for this architecture,
and in fact are hardcoded to true inside NetBSD kernel.
Differential Revision: https://reviews.llvm.org/D63554
llvm-svn: 363823
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Summary:
This patch makes the DIERef class always valid by default constructor
and operator bool. This allows one to express the validity of a DIERef
in the type system. Places which are working with potentially-invalid
DIERefs have been updated to use Optional<DIERef> instead.
The constructor taking a DWARFFormValue was not needed, as all places
which were constructing a DIERef this way were immediately converting it
into a DWARFDIE or a user_id. This can be done without constructing an
intermediate DIERef.
Reviewers: JDevlieghere, clayborg, aprantl
Subscribers: arphaman, lldb-commits
Differential Revision: https://reviews.llvm.org/D63399
llvm-svn: 363767
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Summary:
This is the fifth patch to improve module loading in a series that started here (where I explain the motivation and solution): D62499
Reading strings with ReadMemory is really slow when reading the path of the shared library. This is because we don't know the length of the path so use PATH_MAX (4096) and these strings are actually super close to the boundary of an unreadable page. So even though we use process_vm_readv it will usually fail because the read size spans to the unreadable page and we then default to read the string word by word with ptrace.
This new function is very similar to another ReadCStringFromMemory that already exists in lldb that makes sure it never reads cross page boundaries and checks if we already read the entire string by finding '\0'.
I was able to reduce the GetLoadedSharedLibraries call from 30ms to 4ms (or something of that order).
Reviewers: clayborg, xiaobai, labath
Reviewed By: labath
Subscribers: emaste, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D62503
llvm-svn: 363750
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Summary:
This is the fourth patch to improve module loading in a series that started here (where I explain the motivation and solution): D62499
Implement the `xfer:libraries-svr4` packet by adding a new function that generates the list and then in Handle_xfer I generate the XML for it. The XML is really simple so I'm just using string concatenation because I believe it's more readable than having to deal with a DOM api.
Reviewers: clayborg, xiaobai, labath
Reviewed By: labath
Subscribers: emaste, mgorny, srhines, krytarowski, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D62502
llvm-svn: 363707
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Summary:
A user_id_t carries the same information as a DIERef, but it takes up
less space.
Furthermore, DIERef::operator<'s implementation is very
questionable, as it does not take the cu_offset and section fields into
account. Using just the die offset was correct in the days when all
debug info lived in a single section, but since we started supporting
DWO debug info, this was no longer true. The comparison operator could
be fixed, but it seems like using the user_id_t for these purposes is a
better idea overall.
I think this did not cause any bugs, because the only place the
comparison operator was used is in m_function_scope_qualified_name_map,
and this one is local to a dwo file, but I am not 100% sure of that.
Reviewers: clayborg, JDevlieghere
Subscribers: aprantl, lldb-commits
Differential Revision: https://reviews.llvm.org/D63322
llvm-svn: 363528
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Summary:
This is the third patch to improve module loading in a series that started here (where I explain the motivation and solution): D62499
Add functions to read the r_debug location to know where the linked list of loaded libraries are so I can generate the `xfer:libraries-svr4` packet.
I'm also using this function to implement `GetSharedLibraryInfoAddress` that was "not implemented" for linux.
Most of this code was inspired by the current ds2 implementation here: https://github.com/facebook/ds2/blob/master/Sources/Target/POSIX/ELFProcess.cpp.
Reviewers: clayborg, xiaobai, labath
Reviewed By: clayborg, labath
Subscribers: emaste, krytarowski, mgorny, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D62501
llvm-svn: 363458
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Improve manual indexing performance when indexing non objective C code.
Differential Revision: https://reviews.llvm.org/D63171
llvm-svn: 363441
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llvm-svn: 363400
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llvm-svn: 363382
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Previously it was storing a *pointer*, which left open the possibility
of this pointer being null. We never made use of that possibility (it
does not make sense), and most of the code was already assuming that.
However, there were a couple of null-checks scattered around the code.
This patch replaces the reference with a pointer, making the
non-null-ness explicit, and removes the remaining null-checks.
llvm-svn: 363381
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In a dwo/debug_types world, the die offset is not enough to uniquely
idendify a debug info entry. Pass the the entire DIERef object instead.
This is technically NFC, because only AppleIndex implemented this
method (and there, the die offset *is* enough for unique
identification). However, this makes the code simpler, and simplifies
some of the follow-up patches.
llvm-svn: 363373
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Summary:
this revision adds Lexing, Parsing and Basic Semantic for the consteval specifier as specified by http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1073r3.html
with this patch, the consteval specifier is treated as constexpr but can only be applied to function declaration.
Changes:
- add the consteval keyword.
- add parsing of consteval specifier for normal declarations and lambdas expressions.
- add the whether a declaration is constexpr is now represented by and enum everywhere except for variable because they can't be consteval.
- adapt diagnostic about constexpr to print constexpr or consteval depending on the case.
- add tests for basic semantic.
Reviewers: rsmith, martong, shafik
Reviewed By: rsmith
Subscribers: eraman, efriedma, rnkovacs, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61790
llvm-svn: 363362
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Summary:
Type units don't represent actual compilations and a lot of the
operations that we do with lldb compile units (getting their line
tables, variables, etc.) don't make sense for them. There is also a lot
more of them (sometimes over 100x), so making them more lightweight pays
off.
The main change in this patch is that we stop creating lldb CompileUnits
for DWARF type units. The trickiest part here is that the SymbolFile
interface requires that we assign consecutive sequence IDs to the
compile units we create. As DWARF type and compile units can come in any
order (in v5), this means we can no longer use 1-1 mapping between DWARF
and lldb compile units. Instead I build a translation table between the
two indices. To avoid pessimizing the case where there are no type
units, I build the translation table only in case we have at least one
type unit.
Additionaly, I also tried to strenghted type safete by replacing
DWARFUnit with DWARFCompileUnit where applicable. Though that was not
stricly necessary, I found it a good way to ensure that the
transformations I am doing here make sense. In the places where I was
changing the function signatures, and where it was obvious that the
objects being handled were not null, I also replaced pointers with
references.
There shouldn't be any major functional change with this patch. The only
change I observed is that now the types in the type units will not be
parsed when one calls Module::ParseAllDebugSymbols, unless they are
referenced from other compile units. This makes sense, given how
ParseAllDebugSymbols is implemented (it iterates over all compile
units), and it only matters for one hand-writted test where I did not
bother to reference the types from the compile units (which I now do).
Reviewers: clayborg, JDevlieghere, aprantl
Subscribers: jdoerfert, lldb-commits
Differential Revision: https://reviews.llvm.org/D63005
llvm-svn: 363250
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This replaces the `info` typedef with a nested struct named Info. This
means we now have FooProvider and FooProvider::Info, instead of two
related but separate classes FooProvider and FooInfo. This change is
mostly cosmetic.
llvm-svn: 363211
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with a call to snprintf() to find the size of the formatted string,
malloc memory, then snprintf again to format it into the buffer, instead
of calling asprintf.
Orig commit msg:
When reading ObjC class table, use new SPI if it is avail
In the latest OS betas, the objc runtime has a special interface
for the debugger, class_getNameRaw(), instead of the existing
class_getName(), which will return class names in their raw, unmangled
(in the case of swift) form. When lldb can access the unmangled
names of classes, it won't need to fetch them out of the inferior
process after we run our "get the objc class table" expression.
If the new interface is absent (debugging a process on an older
target), lldb will fall back to class_getName and reading any class
names that it got back in demangled form, at a bit of a performance
cost on the first expression.
<rdar://problem/50688054>
llvm-svn: 363206
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Summary:
PersistentStateExpressions (e.g. ClangPersistentVariables) have the
ability to define types using expressions that persist throughout the
debugging session. GetCompilerTypeFromPersistentDecl is a useful
operation to have if you need to use any of those persistently declared types,
like in CommandObjectMemory.
This decouples clang from CommandObjectMemory and decouples Plugins from
Commands in general.
Differential Revision: https://reviews.llvm.org/D62797
llvm-svn: 363183
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This is a preparatory patch to allow reading type units from dwo files.
llvm-svn: 363146
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Summary:
This patch creates a cache of file lists in line tables referenced by
type units. This cache is used to avoid parsing a line table twice
(since a file list will generally be shared by many type units).
It also sets things up in a way that parsing of DW_AT_decl_file
attributes will keep working even when we stop creating lldb compile
units for dwarf type units, but it stops short of actually doing that.
This means that the request for files now go directly to SymbolFileDWARF
instead of being routed there indirectly via the
lldb_private::CompileUnit class.
As a result of this, a number of occurences of SymbolContext variables
in DWARFASTParserClang have become unused, so I remove them.
This patch reduces the number of times a file list is being parsed, but
the situation is still suboptimal, as the parsed list is being copied
multiple times. This will be fixed when we stop creating CompileUnits
for DWARF type units.
Reviewers: clayborg, aprantl, JDevlieghere
Subscribers: jdoerfert, lldb-commits
Differential Revision: https://reviews.llvm.org/D62894
llvm-svn: 363143
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The auxiliary vector method had the wrong signature.
Reviewers: MaskRay, teemperor, aadsm
Reviewed By: MaskRay, teemperor
Differential Revision: https://reviews.llvm.org/D63187
llvm-svn: 363135
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because it breaks the windows bot - asprintf() is not available.
llvm-svn: 363115
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llvm-svn: 363109
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In the latest OS betas, the objc runtime has a special interface
for the debugger, class_getNameRaw(), instead of the existing
class_getName(), which will return class names in their raw, unmangled
(in the case of swift) form. When lldb can access the unmangled
names of classes, it won't need to fetch them out of the inferior
process after we run our "get the objc class table" expression.
If the new interface is absent (debugging a process on an older
target), lldb will fall back to class_getName and reading any class
names that it got back in demangled form, at a bit of a performance
cost on the first expression.
<rdar://problem/50688054>
llvm-svn: 363103
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Summary:
This is the second patch to improve module loading in a series that started here (where I explain the motivation and solution): https://reviews.llvm.org/D62499
I need to read the aux vector to know where the r_debug map with the loaded libraries are.
The AuxVector class was made generic so it could be reused between the POSIX-DYLD plugin and NativeProcess*. The class itself ended up in the ProcessUtility plugin.
Reviewers: clayborg, xiaobai, labath, JDevlieghere
Reviewed By: clayborg, labath, JDevlieghere
Subscribers: emaste, JDevlieghere, mgorny, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D62500
llvm-svn: 363098
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This is a followup to rL362981, in which I moved GetObjCLanguageRuntime
from Process to ObjCLanguageRuntime, renaming it to Get along the way.
llvm-svn: 362984
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Summary:
This is the first of a few patches I have to improve the performance of dynamic module loading on Android.
In this first diff I'll describe the context of my main motivation and will then link to it in the other diffs to avoid repeating myself.
## Motivation
I have a few scenarios where opening a specific feature on an Android app takes around 40s when lldb is attached to it. The reason for that is because 40 modules are dynamicly loaded at that point in time and each one of them is taking ~1s.
## The problem
To learn about new modules we have a breakpoint on a linker function that is called twice whenever a module is loaded. One time just before it's loaded (so lldb can check which modules are loaded) and another right after it's loaded (so lldb can check again which ones are loaded and calculate the diference).
It's figuring out which modules are loaded that is taking quite some time. This is currently done by traversing the linked list of loaded shared libraries that the linker maintains in memory. Each item in the linked list requires its own `x` packet sent to the gdb server (this is android so the network also plays a part). In my scenario there are 400+ loaded libraries and even though we read 0x800 worth of bytes at a time we still make ~180 requests that end up taking 150-200ms.
We also do this twice, once before the module is loaded (state = eAdd) and another right after (state = eConsistent) which easly adds up to ~400ms per module.
## A solution
**Implement `xfer:libraries-svr4` in lldb-server:**
I noticed in the code that loads the new modules that it had support for the `xfer:libraries-svr4` packet (added ~4 years ago to support the ds2 debug server) but we didn't support it in lldb-server. This single packet returns an xml list of all the loaded modules by the process. The advantage is that there's no more need to make 180 requests to read the linked list. Additionally this new requests takes around 10ms.
**More efficient usage of the `xfer:libraries-svr4` packet in lldb:**
When `xfer:libraries-svr4` is available the Process class has a `LoadModules` function that requests this packet and then loads or unloads modules based on the current list of loaded modules by the process.
This is the function that is used by the DYLDRendezvous class to get the list of loaded modules before and after the module is loaded. However, this is really not needed since the LoadModules function already loaded or unloaded the modules accordingly. I changed this strategy to call LoadModules only once (after the process has loaded the module).
**Bugs**
I found a few issues in lldb while implementing this and have submitted independent patches for them.
I tried to devide this into multiple logical patches to make it easier to review and discuss.
## Tests
I wanted to put these set of diffs up before having all the tests up and running to start having them reviewed from a techical point of view. I'm also having some trouble making the tests running on linux so I need more time to make that happen.
# This diff
The `xfer` packages follow the same protocol, they are requested with `xfer:<object>:<read|write>:<annex>:<offset,length>` and a return that starts with `l` or `m` depending if the offset and length covers the entire data or not. Before implementing the `xfer:libraries-svr4` I refactored the `xfer:auxv` to generically handle xfer packets so we can easly add new ones.
The overall structure of the function ends up being:
* Parse the packet into its components: object, offset etc.
* Depending on the object do its own logic to generate the data.
* Return the data based on its size, the requested offset and length.
Reviewers: clayborg, xiaobai, labath
Reviewed By: labath
Subscribers: mgorny, krytarowski, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D62499
llvm-svn: 362982
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Summary:
In an effort to make Process more language agnostic, I removed
GetCPPLanguageRuntime from Process. I'm following up now with an equivalent
change for ObjC.
Differential Revision: https://reviews.llvm.org/D63052
llvm-svn: 362981
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