Teach libDebugInfo (llvm-dwarfdump) and lldb about DWARF tags and
attributes for pointer authentication. These values have been emitted by
Apple clang for several releases. Although upstream LLVM doesn't emit
these values yet, we hope to upstream that part sometime soon.
Differential revision: https://reviews.llvm.org/D130215
The DumpDataExtractor function had two branches for printing floating
point values. One branch (APFloat) was used if we had a Target object
around and could query it for the appropriate semantics. If we didn't
have a Target, we used host operations to read and format the value.
This patch changes second path to use APFloat as well. To make it work,
I pick reasonable defaults for different byte size. Notably, I did not
include x87 long double in that list (as it is ambibuous and
architecture-specific). This exposed a bug where we were printing
register values using the target-less branch, even though the registers
definitely belong to a target, and we had it available. Fixing this
prompted the update of several tests for register values due to slightly
different floating point outputs.
The most dubious aspect of this patch is the change in
TypeSystemClang::GetFloatTypeSemantics to recognize `10` as a valid size
for x87 long double. This was necessary because because sizeof(long
double) on x86_64 is 16 even though it only holds 10 bytes of useful
data. This generalizes the hackaround present in the target-free branch
of the dumping function.
Differential Revision: https://reviews.llvm.org/D129750
Without this patch, clang will not wrap in an ElaboratedType node types written
without a keyword and nested name qualifier, which goes against the intent that
we should produce an AST which retains enough details to recover how things are
written.
The lack of this sugar is incompatible with the intent of the type printer
default policy, which is to print types as written, but to fall back and print
them fully qualified when they are desugared.
An ElaboratedTypeLoc without keyword / NNS uses no storage by itself, but still
requires pointer alignment due to pre-existing bug in the TypeLoc buffer
handling.
---
Troubleshooting list to deal with any breakage seen with this patch:
1) The most likely effect one would see by this patch is a change in how
a type is printed. The type printer will, by design and default,
print types as written. There are customization options there, but
not that many, and they mainly apply to how to print a type that we
somehow failed to track how it was written. This patch fixes a
problem where we failed to distinguish between a type
that was written without any elaborated-type qualifiers,
such as a 'struct'/'class' tags and name spacifiers such as 'std::',
and one that has been stripped of any 'metadata' that identifies such,
the so called canonical types.
Example:
```
namespace foo {
struct A {};
A a;
};
```
If one were to print the type of `foo::a`, prior to this patch, this
would result in `foo::A`. This is how the type printer would have,
by default, printed the canonical type of A as well.
As soon as you add any name qualifiers to A, the type printer would
suddenly start accurately printing the type as written. This patch
will make it print it accurately even when written without
qualifiers, so we will just print `A` for the initial example, as
the user did not really write that `foo::` namespace qualifier.
2) This patch could expose a bug in some AST matcher. Matching types
is harder to get right when there is sugar involved. For example,
if you want to match a type against being a pointer to some type A,
then you have to account for getting a type that is sugar for a
pointer to A, or being a pointer to sugar to A, or both! Usually
you would get the second part wrong, and this would work for a
very simple test where you don't use any name qualifiers, but
you would discover is broken when you do. The usual fix is to
either use the matcher which strips sugar, which is annoying
to use as for example if you match an N level pointer, you have
to put N+1 such matchers in there, beginning to end and between
all those levels. But in a lot of cases, if the property you want
to match is present in the canonical type, it's easier and faster
to just match on that... This goes with what is said in 1), if
you want to match against the name of a type, and you want
the name string to be something stable, perhaps matching on
the name of the canonical type is the better choice.
3) This patch could expose a bug in how you get the source range of some
TypeLoc. For some reason, a lot of code is using getLocalSourceRange(),
which only looks at the given TypeLoc node. This patch introduces a new,
and more common TypeLoc node which contains no source locations on itself.
This is not an inovation here, and some other, more rare TypeLoc nodes could
also have this property, but if you use getLocalSourceRange on them, it's not
going to return any valid locations, because it doesn't have any. The right fix
here is to always use getSourceRange() or getBeginLoc/getEndLoc which will dive
into the inner TypeLoc to get the source range if it doesn't find it on the
top level one. You can use getLocalSourceRange if you are really into
micro-optimizations and you have some outside knowledge that the TypeLocs you are
dealing with will always include some source location.
4) Exposed a bug somewhere in the use of the normal clang type class API, where you
have some type, you want to see if that type is some particular kind, you try a
`dyn_cast` such as `dyn_cast<TypedefType>` and that fails because now you have an
ElaboratedType which has a TypeDefType inside of it, which is what you wanted to match.
Again, like 2), this would usually have been tested poorly with some simple tests with
no qualifications, and would have been broken had there been any other kind of type sugar,
be it an ElaboratedType or a TemplateSpecializationType or a SubstTemplateParmType.
The usual fix here is to use `getAs` instead of `dyn_cast`, which will look deeper
into the type. Or use `getAsAdjusted` when dealing with TypeLocs.
For some reason the API is inconsistent there and on TypeLocs getAs behaves like a dyn_cast.
5) It could be a bug in this patch perhaps.
Let me know if you need any help!
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D112374
Refactor the string conversion of the `lldb::InstructionControlFlowKind` enum out
of `Instruction::Dump` to enable reuse of this logic by the
JSON TraceDumper (to be implemented in separate diff).
Will coordinate the landing of this change with D130320 since there will be a minor merge conflict between
these changes.
Test Plan:
Run unittests
```
> ninja check-lldb
[4/5] Running lldb unit test suite
Testing Time: 10.13s
Passed: 1084
```
Verify '-k' flag's output
```
(lldb) thread trace dump instructions -k
thread #1: tid = 1375377
libstdc++.so.6`std::ostream::flush() + 43
7048: 0x00007ffff7b54dab return retq
7047: 0x00007ffff7b54daa other popq %rbx
7046: 0x00007ffff7b54da7 other movq %rbx, %rax
7045: 0x00007ffff7b54da5 cond jump je 0x11adb0 ; <+48>
7044: 0x00007ffff7b54da2 other cmpl $-0x1, %eax
libc.so.6`_IO_fflush + 249
7043: 0x00007ffff7161729 return retq
7042: 0x00007ffff7161728 other popq %rbp
7041: 0x00007ffff7161727 other popq %rbx
7040: 0x00007ffff7161725 other movl %edx, %eax
7039: 0x00007ffff7161721 other addq $0x8, %rsp
7038: 0x00007ffff7161709 cond jump je 0x87721 ; <+241>
7037: 0x00007ffff7161707 other decl (%rsi)
7036: 0x00007ffff71616fe cond jump je 0x87707 ; <+215>
7035: 0x00007ffff71616f7 other cmpl $0x0, 0x33de92(%rip) ; __libc_multiple_threads
7034: 0x00007ffff71616ef other movq $0x0, 0x8(%rsi)
7033: 0x00007ffff71616ed cond jump jne 0x87721 ; <+241>
7032: 0x00007ffff71616e9 other subl $0x1, 0x4(%rsi)
7031: 0x00007ffff71616e2 other movq 0x88(%rbx), %rsi
7030: 0x00007ffff71616e0 cond jump jne 0x87721 ; <+241>
7029: 0x00007ffff71616da other testl $0x8000, (%rbx) ; imm = 0x8000
```
Differential Revision: https://reviews.llvm.org/D130580
TestStackFromStdModule.py started failing due to f4fb72e6d4
(https://reviews.llvm.org/D128146), with a clang assertion failure:
assert(isa<InjectedClassNameType>(Decl->TypeForDecl))
This diff move the logic of `GetControlFlowKind()` from Disassembler.cpp to DisassemblerLLVMC.cpp.
Here's details:
- Actual logic of GetControlFlowKind() move to `DisassemblerLLVMC.cpp`, and we can check underlying architecture using `DisassemblerScope` there.
- With this change, passing 'triple' to `GetControlFlowKind()` is no more required.
Reviewed By: wallace
Differential Revision: https://reviews.llvm.org/D130320
This can cause a deadlock if other threads use the common pattern of
"lock the StackFrameList, get a frame, lock the StackFrame."
Differential Revision: https://reviews.llvm.org/D130524
Some codepaths lead to `namespace_map == nullptr` when we get to
`ClangASTSource::FindCompleteType`. This occurred while debugging
an lldb session that had `settings set target.import-std-module true`.
In that case, with `LLDBLog::Expressions` logging enabled, we would
dereference a `nullptr` and crash.
This commit moves the logging until after we check for `nullptr`.
**Testing**
* Fixed the specific crash I was seeing while debugging an `lldb`
session with `import-std-module` enabled.
Differential Revision: https://reviews.llvm.org/D130561
Previously we just checked via S regs and were not checking
memory content after pushes.
The vpush test confirms that the fix in https://reviews.llvm.org/D130307
is working.
Memory will only be checked if an "after" state is provided.
Reviewed By: clayborg
Differential Revision: https://reviews.llvm.org/D130468
* Look for files that end width arm/thumb.dat,
meaning we don't try to run, for example, vim swap files.
* Print the name of the test that failed.
Reviewed By: clayborg
Differential Revision: https://reviews.llvm.org/D130467
Also correct the test failed message. It implies that what
it's done is compare the 'before' and 'ater' states from the
test input.
Except that that's the whole point of the test, that the state changes.
It should tell you that it compared the result of the emulation to the
'after'.
Reviewed By: clayborg
Differential Revision: https://reviews.llvm.org/D130464
Since some s and d registers overlap we will error if we find both.
This prevents you overwriting one with the other in a test case.
Reviewed By: clayborg
Differential Revision: https://reviews.llvm.org/D130462
This teaches ProcessElfCore to recognise the MTE tag segments.
https://www.kernel.org/doc/html/latest/arm64/memory-tagging-extension.html#core-dump-support
These segments contain all the tags for a matching memory segment
which will have the same size in virtual address terms. In real terms
it's 2 tags per byte so the data in the segment is much smaller.
Since MTE is the only tag type supported I have hardcoded some
things to those values. We could and should support more formats
as they appear but doing so now would leave code untested until that
happens.
A few things to note:
* /proc/pid/smaps is not in the core file, only the details you have
in "maps". Meaning we mark a region tagged only if it has a tag segment.
* A core file supports memory tagging if it has at least 1 memory
tag segment, there is no other flag we can check to tell if memory
tagging was enabled. (unlike a live process that can support memory
tagging even if there are currently no tagged memory regions)
Tests have been added at the commands level for a core file with
mte and without.
There is a lot of overlap between the "memory tag read" tests here and the unit tests for
MemoryTagManagerAArch64MTE::UnpackTagsFromCoreFileSegment, but I think it's
worth keeping to check ProcessElfCore doesn't cause an assert.
Depends on D129487
Reviewed By: omjavaid
Differential Revision: https://reviews.llvm.org/D129489
Refactor the code responsible for sending the "k" packet and move it
into GDBRemoteCommunicationClient::KillProcess() method. This is part
of refactoring to enable multiprocess support in the client,
and to support using the vKill packet instead.
As part of the refactoring, the following functional changes apply:
- Some redundant logging has been removed, as any failures are returned
via exit_string anyway.
- SetLastStopPacket() is no longer called. It is used only to populate
the thread list, and since the process has just exited and we're
terminating the process instance, there's really no reason to set it.
- On successful kill, exit_string is set to "killed", to clearly
indicate that the process has terminated on our request rather than
on its own.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D130340
Make compiler-rt an LLDB test dependency if the corresponding target
exists. Similarly we already have `asan` and `tsan` as optional test
dependencies, but we need the `compiler-rt` target when enabling
compiler-rt trough LLVM_ENABLE_RUNTIMES.
This is the first part of support for reading MTE tags from Linux
core files. The format is documented here:
https://www.kernel.org/doc/html/latest/arm64/memory-tagging-extension.html#core-dump-support
This patch adds a method to unpack from the format the core
file uses, which is different to the one chosen for GDB packets.
MemoryTagManagerAArch64MTE is not tied one OS so another OS
might choose a different format in future. However, infrastructure
to handle that would go untested until then so I've chosen not to
attempt to handle that.
Reviewed By: omjavaid
Differential Revision: https://reviews.llvm.org/D129487
This commit adds a fuzzer for LLDB's expression evaluator.
The fuzzer takes a different approach than the current fuzzers
present, and uses an approach that is currently being used for
clang fuzzers.
Instead of fuzzing the evaluator with randomly mutated
characters, protobufs are used to generate a subset of C++. This
is then converted to valid C++ code and sent to the expression
evaluator. In addition, libprotobuf_mutator is used to mutate
the fuzzer's inputs from valid C++ code to valid C++ code, rather
than mutating from valid code to total nonsense.
Differential revision: https://reviews.llvm.org/D129377
Checking if a path is absolute can be expensive and currently the result is not cached in the FileSpec object. This patch adds caching and also code to clear the cache if the file is modified.
Differential Revision: https://reviews.llvm.org/D130396
The FileSpect APIs allow users to modify instance variables directly by getting a non const reference to the directory and filename instance variables. This makes it impossibly to control all of the times the FileSpec object is modified so we can clear the cache. This patch modifies the APIs of FileSpec so no one can modify the directory or filename directly by adding set accessors and by removing the get accessors that are non const.
Many clients were using FileSpec::GetCString(...) which returned a unique C string from a ConstString'ified version of the result of GetPath() which returned a std::string. This caused many locations to use this convenient function incorrectly and could cause many strings to be added to the constant string pool that didn't need to. Most clients were converted to using FileSpec::GetPath().c_str() when possible. Other clients were modified to use the newly renamed version of this function which returns an actualy ConstString:
ConstString FileSpec::GetPathAsConstString(bool denormalize = true) const;
This avoids the issue where people were getting an already uniqued "const char *" that came from a ConstString only to put the "const char *" back into a "ConstString" object. By returning the ConstString instead of a "const char *" clients can be more efficient with the result.
The patch:
- Removes the non const GetDirectory() and GetFilename() get accessors
- Adds set accessors to replace the above functions: SetDirectory() and SetFilename().
- Adds ClearDirectory() and ClearFilename() to replace usage of the FileSpec::GetDirectory().Clear()/FileSpec::GetFilename().Clear() call sites
- Fixed all incorrect usage of FileSpec::GetCString() to use FileSpec::GetPath().c_str() where appropriate, and updated other call sites that wanted a ConstString to use the newly returned ConstString appropriately and efficiently.
Differential Revision: https://reviews.llvm.org/D130309
Previously you got:
AssertionError: False is not True : Emulation test succeeded.
Which is a bit of a head scratcher. The message is used when
the test fails, not when it succeeds.
DW_OP_skip/DW_OP_bra can move offset to the end of the data, which means that this was the last instruction to execute and the interpreter should terminate.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D130285
This patch adds support for evaluating expressions which reference
a captured `this` from within the context of a C++ lambda expression.
Currently LLDB doesn't provide Clang with enough information to
determine that we're inside a lambda expression and are allowed to
access variables on a captured `this`; instead Clang simply fails
to parse the expression.
There are two problems to solve here:
1. Make sure `clang::Sema` doesn't reject the expression due to an
illegal member access.
2. Materialize all the captured variables/member variables required
to evaluate the expression.
To address (1), we currently import the outer structure's AST context
onto `$__lldb_class`, making the `contextClass` and the `NamingClass`
match, a requirement by `clang::Sema::BuildPossibleImplicitMemberExpr`.
To address (2), we inject all captured variables as locals into the
expression source code.
**Testing**
* Added API test
This is required in preparation for the follow-up patch which adds
support for evaluating expressions from within C++ lambdas. In such
cases we need to materialize variables which are not part of the
current frame but instead are ivars on a 'this' pointer of the current
frame.
Using invalidated vector iterator is at best a UB and could crash depending on STL implementation.
Fixing via minimal changes to preserve the existing code style.
Coverity warning 1454828 (scan.coverity.com)
Differential Revision: https://reviews.llvm.org/D130312
Extract a bit of copy/pasted regex filtering logic into a separate
function and simplify it a little bit.
Differential Revision: https://reviews.llvm.org/D130219
Update the process ID after handling fork/vfork to ensure that
the process plugin reports the correct PID immediately.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D130037
`IntegerLiteral::Create` operates on integer types. For that reason
when we parse DWARF into an AST, when we encounter a constant
initialized enum member variable, we try to determine the underlying
integer type before creating the `IntegerLiteral`. However, we
currently don't desugar the type and for enum typedefs
`dyn_cast<EnumType>` fails. In debug builds this triggers following
assert:
```
Assertion failed: (type->isIntegerType() && "Illegal type in IntegerLiteral"), function IntegerLiteral, file Expr.cpp, line 892
```
This patch turns the `dyn_cast<EnumType>` into a `getAs<EnumType>`
which `dyn_cast`s the canonical type, allowing us to get to the
underlying integer type.
**Testing**
* API test
* Manual repro is fixed
Differential Revision: https://reviews.llvm.org/D130213
This patch adds support for formatting `std::map::const_iterator`.
It's just a matter of adding `const_` to the existing regex.
**Testing**
* Added test case to existing API tests
Differential Revision: https://reviews.llvm.org/D129962
This reverts commit 5778ada8e5.
The watchpoint tests all stall on aarch64-ubuntu bots. Reverting till I can
get my hands on an system to test this out.
This reverts commit 555ae5b8f5.
Apparently, there's something different about how Linux ARM handles watchpoints,
as all the watchpoint tests seem to stall on the Ubuntu aarch64 bots.
Reverting till I can get my hands on a linux system and see what is
wrong.
That was causing hit counts to be double-counted on x86_64 Linux.
It looks like StopInfoWatchpoint::ShouldStopSynchronous gets called
twice for a give stop on Linux (not on Darwin). I had taken out the
"have I been called already" check when I reworked this part of the
code because it didn't seem necessary. Putting that back in because
it looks like it is on some systems.
We were just emitting "invalid module" w/o saying which module. That's
not particularly helpful.
Differential Revision: https://reviews.llvm.org/D129338
Since we want to present the "new & old" values for watchpoint hits, on architectures,
including the ARM family, that stop before the triggering instruction is run, we need
to single step over the instruction before stopping for realz. This was incorrectly
done directly in the StopInfoWatchpoint::ShouldStop. That causes problems if more than
one thread stops "for a reason" at the same time as the watchpoint, since the other actions
didn't expect the process to make progress in this part of the execution control machinery.
The correct way to do this is to schedule the step over using ThreadPlans, and then to restore
the stop info after that plan stops, so that the rest of the stop info actions can happen when
all the other threads have handled their immediate actions as well.
Differential Revision: https://reviews.llvm.org/D129814
Enable stdio forwarding when nonstop mode is enabled, and disable it
once it is disabled. This makes it possible to cleanly handle stdio
forwarding while running multiple processes in non-stop mode.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128932
Stop all processes and clear notification queues when disabling non-stop
mode. Ensure that no stop notifications are sent for processes stopped
due to the mode switch.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128893
Fix the response to `?` packet for threads that are running at the time
(in non-stop mode). The previous code would wrongly send or queue
an empty response for them.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128879
Introduce a new %Stdio notification category and use it to send process
output asynchronously when running in non-stop mode. This is an LLDB
extension since GDB does not use the 'O' packet for process output,
just for replies to 'qRcmd' packets.
Using the async notification mechanism implies that only the first
output packet is sent immediately to the client. The client needs
to request subsequent notifications (if any) using the new vStdio packet
(that works pretty much like vStopped for the Stop notification queue).
The packet handler in lldb-server tests is updated to handle the async
stdio packets in addition to the regular O packets. However, due
to the implications noted above, it can only handle the first output
packet sent by the server. Subsequent packets need to be explicitly
requested via vStdio.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128849
Improve handling of multiple successive continue packets in non-stop
mode. More specifically:
1. Explicitly send error response (instead of crashing on assertion)
if the user attempts to resume the same process twice. Since we
do not support thread-level non-stop mode, one needs to always stop
the process explicitly before resuming another thread set.
2. Actually stop the process if "vCont;t" is delivered to a running
process. Similarly, we only support stopping all the running threads
simultaneously (via -1) and return an error in any other case.
With this patch, running multiple processes simultaneously is still
unsupported. The patch also employs a hack to avoid enabling stdio
forwarding on "vCont;t" packet. Both of these issues are addressed
by followup patches.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128710
Improve handling of multiple successive continue packets in non-stop
mode. More specifically:
1. Explicitly send error response (instead of crashing on assertion)
if the user attempts to resume the same process twice. Since we
do not support thread-level non-stop mode, one needs to always stop
the process explicitly before resuming another thread set.
2. Actually stop the process if "vCont;t" is delivered to a running
process. Similarly, we only support stopping all the running threads
simultaneously (via -1) and return an error in any other case.
With this patch, running multiple processes simultaneously is still
unsupported. The patch also employs a hack to avoid enabling stdio
forwarding on "vCont;t" packet. Both of these issues are addressed
by followup patches.
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.llvm.org/D128710
Reland 486787210d which broke tests on Arm and Windows.
* Windows -- on Windows const static data members with no out-of-class
definition do have valid addresses, in constract to other platforms
(Linux, macos) where they don't. Adjusted the test to expect success
on Windows and failure on other platforms.
* Arm -- `int128` is not available on 32-bit ARM, so disable the test
for this architecture.
Print the enum values and their description in the help output for
argument values. Until now, there was no way to get these values and
their description.
Example output:
(lldb) help <description-verbosity>
<description-verbosity> -- How verbose the output of 'po' should be.
compact : Only show the description string
full : Show the full output, including persistent variable's
name and type
Differential revision: https://reviews.llvm.org/D129707
Refactor the command option enum values and the command argument table
to connect the two. This has two benefits:
- We guarantee that two options that use the same argument type have
the same accepted values.
- We can print the enum values and their description in the help
output. (D129707)
Differential revision: https://reviews.llvm.org/D129703
Remove m_inferior_prev_state that's not suitable for multiprocess
debugging and that does not seem to be really used at all.
The only use of the variable right now is to "prevent" sending the stop
reason after attach/launch. However, this code is never actually run
since none of the process plugins actually use eStateLaunching or
eStateAttaching. Through adding an assert, I've confirmed that it's
never hit in any of the LLDB tests or while attaching/launching debugged
process via lldb-server and via lldb CLI.
Differential Revision: https://reviews.llvm.org/D128878
Sponsored by: The FreeBSD Foundation
clang 14 removed -gz=zlib-gnu support and ld.lld/llvm-objcopy removed zlib-gnu
support recently. Remove lldb support by migrating away from
llvm::object::Decompressor::isCompressedELFSection.
The API has another user llvm-dwp, so it is not removed in this patch.
Reviewed By: labath
Differential Revision: https://reviews.llvm.org/D129724
This adds support for using const static integral data members as described by C++11 [class.static.data]p3
to LLDB's expression evaluator.
So far LLDB treated these data members are normal static variables. They already work as intended when they are declared in the class definition and then defined in a namespace scope. However, if they are declared and initialised in the class definition but never defined in a namespace scope, all LLDB expressions that use them will fail to link when LLDB can't find the respective symbol for the variable.
The reason for this is that the data members which are only declared in the class are not emitted into any object file so LLDB can never resolve them. Expressions that use these variables are expected to directly use their constant value if possible. Clang can do this for us during codegen, but it requires that we add the constant value to the VarDecl we generate for these data members.
This patch implements this by:
* parsing the constant values from the debug info and adding it to variable declarations we encounter.
* ensuring that LLDB doesn't implicitly try to take the address of expressions that might be an lvalue that points to such a special data member.
The second change is caused by LLDB's way of storing lvalues in the expression parser. When LLDB parses an expression, it tries to keep the result around via two mechanisms:
1. For lvalues, LLDB generates a static pointer variable and stores the address of the last expression in it: `T *$__lldb_expr_result_ptr = &LastExpression`
2. For everything else, LLDB generates a static variable of the same type as the last expression and then direct initialises that variable: `T $__lldb_expr_result(LastExpression)`
If we try to print a special const static data member via something like `expr Class::Member`, then LLDB will try to take the address of this expression as it's an lvalue. This means LLDB will try to take the address of the variable which causes that Clang can't replace the use with the constant value. There isn't any good way to detect this case (as there a lot of different expressions that could yield an lvalue that points to such a data member), so this patch also changes that we only use the first way of capturing the result if the last expression does not have a type that could potentially indicate it's coming from such a special data member.
This change shouldn't break most workflows for users. The only observable side effect I could find is that the implicit persistent result variables for const int's now have their own memory address:
Before this change:
```
(lldb) p i
(const int) $0 = 123
(lldb) p &$0
(const int *) $1 = 0x00007ffeefbff8e8
(lldb) p &i
(const int *) $2 = 0x00007ffeefbff8e8
```
After this change we capture `i` by value so it has its own value.
```
(lldb) p i
(const int) $0 = 123
(lldb) p &$0
(const int *) $1 = 0x0000000100155320
(lldb) p &i
(const int *) $2 = 0x00007ffeefbff8e8
```
Reviewed By: Michael137
Differential Revision: https://reviews.llvm.org/D81471
Convert the m_debugged_processes map from NativeProcessProtocol pointers
to structs, and combine the additional set(s) holding the additional
process properties into a flag field inside this struct. This is
desirable since there are more properties to come and having a single
structure with all information should be cleaner and more efficient than
using multiple sets for that.
Suggested by Pavel Labath in D128893.
Differential Revision: https://reviews.llvm.org/D129652
jGetLoadedDynamicLibrariesInfos normally checks with dyld to find
the list of binaries loaded in the inferior, and getting the filepath,
before trying to parse the Mach-O binary in inferior memory.
This allows for debugserver to parse a Mach-O binary present in memory,
but not yet registered with dyld. This patch also adds some simple
sanity checks that we're reading a Mach-O header before we begin
stepping through load commands, because we won't have the sanity check
of consulting dyld for the list of loaded binaries before parsing.
Also adds a testcase.
[This patch was reverted after causing a testsuite failure on a CI bot;
I haven't been able to repro the failure outside the CI, but I have a
theory that my sanity check on cputype which only matched arm64 and
x86_64 - and the CI machine may have a watch simulator that is still
using i386.]
Differential Revision: https://reviews.llvm.org/D128956
rdar://95737734
Add `pcm-info` to the `target module dump` subcommands.
This dump command shows information about clang .pcm files. This command
effectively runs `clang -module-file-info` and produces identical output.
The .pcm file format is tightly coupled to the clang version. The clang
embedded in lldb is not guaranteed to match the version of the clang executable
available on the local system.
There have been times when I've needed to view the details about a .pcm file
produced by lldb's embedded clang, but because the clang executable was a
slightly different version, the `-module-file-info` invocation failed. With
this command, users can inspect .pcm files generated by lldb too.
Differential Revision: https://reviews.llvm.org/D129456
It's more natural to use uint8_t * (std::byte needs C++17 and llvm has
too much uint8_t *) and most callers use uint8_t * instead of char *.
The functions are recently moved into `llvm::compression::zlib::`, so
downstream projects need to make adaption anyway.
Thanks to ymeng@fb.com for coming up with this change.
`thread trace dump info` can dump some metrics that can be useful for
analyzing the performance and quality of a trace. This diff adds a --json
option for dumping this information in json format that can be easily
understood my machines.
Differential Revision: https://reviews.llvm.org/D129332
It turns out that cgroup filtering is relatively trivial and works
really nicely. Thid diffs adds automatic cgroup filtering when in
per-cpu mode, unless a new --disable-cgroup-filtering flag is passed in
the start command. At least on Meta machines, all processes are spawned
inside a cgroup by default, which comes super handy, because per cpu
tracing is now much more precise.
A manual test gave me this result
- Without filtering:
Total number of trace items: 36083
Total number of continuous executions found: 229
Number of continuous executions for this thread: 2
Total number of PSB blocks found: 98
Number of PSB blocks for this thread 2
Total number of unattributed PSB blocks found: 38
- With filtering:
Total number of trace items: 87756
Total number of continuous executions found: 123
Number of continuous executions for this thread: 2
Total number of PSB blocks found: 10
Number of PSB blocks for this thread 3
Total number of unattributed PSB blocks found: 2
Filtering gives us great results. The number of instructions collected
more than double (probalby because we have less noise in the trace), and
we have much less unattributed PSBs blocks and unrelated PSBs in
general. The ones that are unrelated probably belong to other processes
in the same cgroup.
Differential Revision: https://reviews.llvm.org/D129257
Thanks to fredzhou@fb.com for coming up with this feature.
When tracing in per-cpu mode, we have information of in which cpu we are execution each instruction, which comes from the context switch trace. This diff makes this information available as a `cpu changed event`, which an additional accessor in the cursor `GetCPU()`. As cpu changes are very infrequent, any consumer should listen to cpu change events instead of querying the actual cpu of a trace item. Once a cpu change event is seen, the consumer can invoke GetCPU() to get that information. Also, it's possible to invoke GetCPU() on an arbitrary instruction item, which will return the last cpu seen. However, this call is O(logn) and should be used sparingly.
Manually tested with a sample program that starts on cpu 52, then goes to 18, and then goes back to 52.
Differential Revision: https://reviews.llvm.org/D129340
A trace bundle contains many trace files, and, in the case of intel pt, the
largest files are often the context switch traces because they are not
compressed by default. As a way to improve this, I'm adding a --compact option
to the `trace save` command that filters out unwanted processes from the
context switch traces. Eventually we can do the same for intel pt traces as
well.
Differential Revision: https://reviews.llvm.org/D129239
This metric was missing. We were only measuring in per-thread mode, and
this completes the work.
For a sample trace I have, the `dump info` command shows
```
Timing for this thread:
Decoding instructions: 0.12s
```
I also improved a bit the TaskTime function so that callers don't need to
specify the template argument
Differential Revision: https://reviews.llvm.org/D129249
Thanks to rnofenko@fb.com for coming up with these changes.
This diff adds support for passing units in the trace size inputs. For example,
it's now possible to specify 64KB as the trace size, instead of the
problematic 65536. This makes the user experience a bit friendlier.
Differential Revision: https://reviews.llvm.org/D129613
This patch fixes TestConvenienceVariables.test for AArch64 Windows.
Clang/LLD was unable to find printf apparently available as a macro
definition in stdio.h.
This patch fixes TestThreadAPI for AArch64 windows by switching over to
PDB debug info instead of DWARF. This is needed to step over library
functions like printf as there is debug info mismatch between DWARF and
PDB. PDB DWARF interworking is not fully supported by LLDB at the
moment.
This patch fixes marks TestLoadUnload.test_static_init_during_load as
xfail for AArch64 windows. It is failing similar to Linux and already
marked xfail for linux.
Jonas Devlieghere