This patch pushes the error handling boundary for the GetBitSize()
methods from Runtime into the Type and CompilerType APIs. This makes it
easier to diagnose problems thanks to more meaningful error messages
being available. GetBitSize() is often the first thing LLDB asks about a
type, so this method is particularly important for a better user
experience.
rdar://145667239
The old behavior was to return a null string in the error case,when
refactoring the error handling I thought it would be a good idea to
print the error in the description, but that breaks clients that try to
print a description first and then do something else in the error case.
The API is not great but it's clear that in-band errors are also not a
good idea.
rdar://133956263
ValueObject is part of lldbCore for historical reasons, but conceptually
it deserves to be its own library. This does introduce a (link-time) circular
dependency between lldbCore and lldbValueObject, which is unfortunate
but probably unavoidable because so many things in LLDB rely on
ValueObject. We already have cycles and these libraries are never built
as dylibs so while this doesn't improve the situation, it also doesn't
make things worse.
The header includes were updated with the following command:
```
find . -type f -exec sed -i.bak "s%include \"lldb/Core/ValueObject%include \"lldb/ValueObject/ValueObject%" '{}' \;
```
Our customers is reporting a serious performance issue (expanding a this
pointer takes 70 seconds in VSCode) in a specific execution context.
Profiling shows the hot path is triggered by an expression evaluation
from libStdC++ synthetic children provider for `std::vector<bool>` since
it uses `CreateValueFromExpression()`.
This PR added a new `SBValue::CreateBoolValue()` API and switch
`std::vector<bool>` synthetic children provider to use the new API
without performing expression evaluation.
Note: there might be other cases of `CreateValueFromExpression()` in our
summary/synthetic children providers which I will sweep through in later
PRs.
With this PR, the customer's scenario reduces from 70 seconds => 50
seconds. I will add other PRs to further optimize the remaining 50
seconds (mostly from type/namespace lookup).
Testing:
`test/API/functionalities/data-formatter/data-formatter-stl/libstdcpp/vbool/TestDataFormatterStdVBool.py`
passes with the PR
---------
Co-authored-by: jeffreytan81 <jeffreytan@fb.com>
This patch removes all of the Set.* methods from Status.
This cleanup is part of a series of patches that make it harder use the
anti-pattern of keeping a long-lives Status object around and updating
it while dropping any errors it contains on the floor.
This patch is largely NFC, the more interesting next steps this enables
is to:
1. remove Status.Clear()
2. assert that Status::operator=() never overwrites an error
3. remove Status::operator=()
Note that step (2) will bring 90% of the benefits for users, and step
(3) will dramatically clean up the error handling code in various
places. In the end my goal is to convert all APIs that are of the form
` ResultTy DoFoo(Status& error)
`
to
` llvm::Expected<ResultTy> DoFoo()
`
How to read this patch?
The interesting changes are in Status.h and Status.cpp, all other
changes are mostly
` perl -pi -e 's/\.SetErrorString/ = Status::FromErrorString/g' $(git
grep -l SetErrorString lldb/source)
`
plus the occasional manual cleanup.
This change by itself has no measurable effect on the LLDB
testsuite. I'm making it in preparation for threading through more
errors in the Swift language plugin.
Create additional helper functions for the ValueObject class, for:
- returning the value as an APSInt or APFloat
- additional type casting options
- additional ways to create ValueObjects from various types of data
- dereferencing a ValueObject
These helper functions are needed for implementing the Data Inspection
Language, described in
https://discourse.llvm.org/t/rfc-data-inspection-language/69893
I previously added this API via https://reviews.llvm.org/D142792 in
2023, along with changes to the ValueObject class to treat pointer types
as addresses, and to annotate those ValueObjects with the original
uint64_t byte sequence AND the name of the symbol once stripped, if that
points to a symbol.
I did this unconditionally for all pointer type ValueObjects, and it
caused several regressions in the Objective-C data formatters which have
a ValueObject of an object, it has the address of its class -- but with
ObjC, sometimes it is a "tagged pointer" which is metadata, not an
actual pointer. (e.g. a small NSInteger value is stored entirely in the
tagged pointer, instead of a separate object) Treating these
not-addresses as addresses -- clearing the non-addressable-bits -- is
invalid.
The original version of this patch we're using downstream only does this
bits clearing for pointer types that are specifically decorated with the
pointerauth typequal, but not all of those clang changes are upstreamed
to github main yet, so I tried this simpler approach and hit the tagged
pointer issue and bailed on the whole patch.
This patch, however, is simply adding SBValue::GetValueAsAddress so
script writers who know that an SBValue has an address in memory, can
strip off any metadata. It's an important API to have for script writers
when AArch64 ptrauth is in use, so I'm going to put this part of the
patch back on github main now until we can get the rest of that original
patch upstreamed.
Change GetNumChildren()/CalculateNumChildren() methods return
llvm::Expected
This is an NFC change that does not yet add any error handling or change
any code to return any errors.
This is the second big change in the patch series started with
https://github.com/llvm/llvm-project/pull/83501
A follow-up PR will wire up error handling.
Change GetNumChildren()/CalculateNumChildren() methods return
llvm::Expected
This is an NFC change that does not yet add any error handling or change
any code to return any errors.
This is the second big change in the patch series started with
https://github.com/llvm/llvm-project/pull/83501
A follow-up PR will wire up error handling.
The function was using the default version of ValueObject::Dump, which
has a default of using the synthetic-ness of the top-level value for
determining whether to print _all_ values as synthetic. This resulted in
some unusual behavior, where e.g. a std::vector is stringified as
synthetic if its dumped as the top level object, but in its raw form if
it is a member of a struct without a pretty printer.
The SBValue class already has properties which determine whether one
should be looking at the synthetic view of the object (and also whether
to use dynamic types), so it seems more natural to use that.
Add the ability to get a C++ vtable ValueObject from another
ValueObject.
This patch adds the ability to ask a ValueObject for a ValueObject that
represents the virtual function table for a C++ class. If the
ValueObject is not a C++ class with a vtable, a valid ValueObject value
will be returned that contains an appropriate error. If it is successful
a valid ValueObject that represents vtable will be returned. The
ValueObject that is returned will have a name that matches the demangled
value for a C++ vtable mangled name like "vtable for <class-name>". It
will have N children, one for each virtual function pointer. Each
child's value is the function pointer itself, the summary is the
symbolication of this function pointer, and the type will be a valid
function pointer from the debug info if there is debug information
corresponding to the virtual function pointer.
The vtable SBValue will have the following:
- SBValue::GetName() returns "vtable for <class>"
- SBValue::GetValue() returns a string representation of the vtable
address
- SBValue::GetSummary() returns NULL
- SBValue::GetType() returns a type appropriate for a uintptr_t type for
the current process
- SBValue::GetLoadAddress() returns the address of the vtable adderess
- SBValue::GetValueAsUnsigned(...) returns the vtable address
- SBValue::GetNumChildren() returns the number of virtual function
pointers in the vtable
- SBValue::GetChildAtIndex(...) returns a SBValue that represents a
virtual function pointer
The child SBValue objects that represent a virtual function pointer has
the following values:
- SBValue::GetName() returns "[%u]" where %u is the vtable function
pointer index
- SBValue::GetValue() returns a string representation of the virtual
function pointer
- SBValue::GetSummary() returns a symbolicated respresentation of the
virtual function pointer
- SBValue::GetType() returns the function prototype type if there is
debug info, or a generic funtion prototype if there is no debug info
- SBValue::GetLoadAddress() returns the address of the virtual function
pointer
- SBValue::GetValueAsUnsigned(...) returns the virtual function pointer
- SBValue::GetNumChildren() returns 0
- SBValue::GetChildAtIndex(...) returns invalid SBValue for any index
Examples of using this API via python:
```
(lldb) script vtable = lldb.frame.FindVariable("shape_ptr").GetVTable()
(lldb) script vtable
vtable for Shape = 0x0000000100004088 {
[0] = 0x0000000100003d20 a.out`Shape::~Shape() at main.cpp:3
[1] = 0x0000000100003e4c a.out`Shape::~Shape() at main.cpp:3
[2] = 0x0000000100003e7c a.out`Shape::area() at main.cpp:4
[3] = 0x0000000100003e3c a.out`Shape::optional() at main.cpp:7
}
(lldb) script c = vtable.GetChildAtIndex(0)
(lldb) script c
(void ()) [0] = 0x0000000100003d20 a.out`Shape::~Shape() at main.cpp:3
```
This reverts commit a7b78cac9a77e3ef6bbbd8ab1a559891dc693401.
With updates to the tests.
TestWatchTaggedAddress.py: Updated the expected watchpoint types,
though I'm not sure there should be a differnt default for the two
ways of setting them, that needs to be confirmed.
TestStepOverWatchpoint.py: Skipped this everywhere because I think
what used to happen is you couldn't put 2 watchpoints on the same
address (after alignment). I guess that this is now allowed because
modify watchpoints aren't accounted for, but likely should be.
Needs investigating.
This reverts commit 933ad5c897ee366759a54869b35b2d7285a92137.
This caused 1 test failure and an unexpected pass on AArch64 Linux:
https://lab.llvm.org/buildbot/#/builders/96/builds/45765
Wasn't reported because the bot was already red at the time.
Watchpoints in lldb can be either 'read', 'write', or 'read/write'. This
is exposing the actual behavior of hardware watchpoints. gdb has a
different behavior: a "write" type watchpoint only stops when the
watched memory region *changes*.
A user is using a watchpoint for one of three reasons:
1. Want to find what is changing/corrupting this memory.
2. Want to find what is writing to this memory.
3. Want to find what is reading from this memory.
I believe (1) is the most common use case for watchpoints, and it
currently can't be done in lldb -- the user needs to continue every time
the same value is written to the watched-memory manually. I think gdb's
behavior is the correct one. There are some use cases where a developer
wants to find every function that writes/reads to/from a memory region,
regardless of value, I want to still allow that functionality.
This is also a bit of groundwork for my large watchpoint support
proposal
https://discourse.llvm.org/t/rfc-large-watchpoint-support-in-lldb/72116
where I will be adding support for AArch64 MASK watchpoints which watch
power-of-2 memory regions. A user might ask to watch 24 bytes, and a
MASK watchpoint stub can do this with a 32-byte MASK watchpoint if it is
properly aligned. And we need to ignore writes to the final 8 bytes of
that watched region, and not show those hits to the user.
This patch adds a new 'modify' watchpoint type and it is the default.
Re-landing this patch after addressing testsuite failures found in CI on
Linux, Intel machines, and windows.
rdar://108234227
Watchpoints in lldb can be either 'read', 'write', or 'read/write'. This
is exposing the actual behavior of hardware watchpoints. gdb has a
different behavior: a "write" type watchpoint only stops when the
watched memory region *changes*.
A user is using a watchpoint for one of three reasons:
1. Want to find what is changing/corrupting this memory.
2. Want to find what is writing to this memory.
3. Want to find what is reading from this memory.
I believe (1) is the most common use case for watchpoints, and it
currently can't be done in lldb -- the user needs to continue every time
the same value is written to the watched-memory manually. I think gdb's
behavior is the correct one. There are some use cases where a developer
wants to find every function that writes/reads to/from a memory region,
regardless of value, I want to still allow that functionality.
This is also a bit of groundwork for my large watchpoint support
proposal
https://discourse.llvm.org/t/rfc-large-watchpoint-support-in-lldb/72116
where I will be adding support for AArch64 MASK watchpoints which watch
power-of-2 memory regions. A user might ask to watch 24 bytes, and a
MASK watchpoint stub can do this with a 32-byte MASK watchpoint if it is
properly aligned. And we need to ignore writes to the final 8 bytes of
that watched region, and not show those hits to the user.
This patch adds a new 'modify' watchpoint type and it is the default.
rdar://108234227
StreamFile subclasses Stream (from lldbUtility) and is backed by a File
(from lldbHost). It does not depend on anything from lldbCore or any of its
sibling libraries, so I think it makes sense for this to live in
lldbHost instead.
Differential Revision: https://reviews.llvm.org/D157460
Existing callers of `GetChildAtIndex` pass true for can_create. This change
makes true the default value, callers don't have to pass an opaque true.
See also D151966 for the same change to `GetChildMemberWithName`.
Differential Revision: https://reviews.llvm.org/D152031
It turns out all existing callers of `GetChildMemberWithName` pass true for `can_create`.
This change makes `true` the default value, callers don't have to pass an opaque true.
Differential Revision: https://reviews.llvm.org/D151966
As with D151615, which changed `GetIndexOfChildMemberWithName` to take a `StringRef`
instead of a `ConstString`, this change does the same for `GetIndexOfChildWithName`.
Differential Revision: https://reviews.llvm.org/D151811
`GetChildMemberWithName` does not need a `ConstString`. This change makes the function
take a `StringRef` instead, which alleviates the need for callers to construct a
`ConstString`. I don't expect this change to improve performance, only ergonomics.
This is in support of Alex's effort to replace `ConstString` where appropriate.
There are related `ValueObject` functions that can also be changed, if this is accepted.
Differential Revision: https://reviews.llvm.org/D151615
LLDB should guarantee that the strings returned by SBAPI methods
live forever. I went through every method that returns a string and made
sure that it was added to the ConstString StringPool before returning if
it wasn't obvious that it was already doing so.
I've also updated the docs to document this behavior.
Differential Revision: https://reviews.llvm.org/D150804
Revert while I investigate two CI bot failures;
the more important is the lldb-arm-ubuntu where
the FixAddress is removing the 0th bit so we're
adding the `actual=` decorator on a string pointer,
```
Got output:
(char *) strptr = 0x00400817 (actual=0x400816) ptr = [{ },{H}]
```
in TestDataFormatterSmartArray.py line 229.
This reverts commit 4d635be2dbadc77522eddc9668697385a3b9f8b4.
On target where metadata is stored in bits that aren't used for
virtual addressing -- AArch64 Top Byte Ignore and pointer authentication
are two examples -- an SBValue object representing a pointer will
return the address with metadata for SBValue::GetValueAsUnsigned.
Users may want to get the virtual address without the metadata;
this new method gives them a way to do this.
Differential Revision: https://reviews.llvm.org/D142792
hold an error should:
(a) return false for IsValid, since that's the current behavior and is
a convenient way to check "should I get the value for this".
(b) preserve the error when an SBValue is made from it, and print the
error in the ValueObjectPrinter.
Make that happen.
Differential Revision: https://reviews.llvm.org/D144664
Applied modernize-use-equals-default clang-tidy check over LLDB.
This check is already present in the lldb/.clang-tidy config.
Differential Revision: https://reviews.llvm.org/D121844
Remove the last remaining references to the reproducers from the
instrumentation. This patch renames the relevant files and macros.
Differential revision: https://reviews.llvm.org/D117712
This patch moves the Declaration class from the Symbol library to the
Core library. This will allow to use it in a more generic fashion and
aims to lower the dependency cycles when it comes to the linking.
The patch also does some cleaning up by making column information
permanent and removing the LLDB_ENABLE_DECLARATION_COLUMNS directives.
Differential revision: https://reviews.llvm.org/D101556
Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
Every call to the protected SBAddress constructor and the SetAddress
method takes the address of a valid object which means we might as well
pass it as a const reference instead of a pointer and drop the null
check.
Differential revision: https://reviews.llvm.org/D88249
This cleanup patch unifies all methods called GetByteSize() in the
ValueObject hierarchy to return an optional, like the methods in
CompilerType do. This means fewer magic 0 values, which could fix bugs
down the road in languages where types can have a size of zero, such
as Swift and C (but not C++).
Differential Revision: https://reviews.llvm.org/D84285
This re-lands the patch with bogus :m_byte_size(0) initalizations removed.
This cleanup patch unifies all methods called GetByteSize() in the
ValueObject hierarchy to return an optional, like the methods in
CompilerType do. This means fewer magic 0 values, which could fix bugs
down the road in languages where types can have a size of zero, such
as Swift and C (but not C++).
Differential Revision: https://reviews.llvm.org/D84285
Summary:
`CalculateSyntheticValue` and `GetSyntheticValue` have a `use_synthetic` parameter
that makes the function do nothing when it's false. We obviously always pass true
to the function (or check that the value we pass is true), because there really isn't
any point calling with function with a `false`. This just removes all of this.
Reviewers: labath, JDevlieghere, davide
Reviewed By: davide
Subscribers: davide
Differential Revision: https://reviews.llvm.org/D79568
I previously removed the code in ValueObject::GetExpressionPath that
took advantage of the parameter `qualify_cxx_base_classes`. As a result,
this is now unused and can be removed.
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
Summary:
A *.cpp file header in LLDB (and in LLDB) should like this:
```
//===-- TestUtilities.cpp -------------------------------------------------===//
```
However in LLDB most of our source files have arbitrary changes to this format and
these changes are spreading through LLDB as folks usually just use the existing
source files as templates for their new files (most notably the unnecessary
editor language indicator `-*- C++ -*-` is spreading and in every review
someone is pointing out that this is wrong, resulting in people pointing out that this
is done in the same way in other files).
This patch removes most of these inconsistencies including the editor language indicators,
all the different missing/additional '-' characters, files that center the file name, missing
trailing `===//` (mostly caused by clang-format breaking the line).
Reviewers: aprantl, espindola, jfb, shafik, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: dexonsmith, wuzish, emaste, sdardis, nemanjai, kbarton, MaskRay, atanasyan, arphaman, jfb, abidh, jsji, JDevlieghere, usaxena95, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D73258
This is a half-implemented feature that as far as we can tell was
never used by anything since its original inclusion in 2014. This
patch removes it to make remaining the code easier to understand.
Differential Revision: https://reviews.llvm.org/D71310
Summary:
NFC = [[ https://llvm.org/docs/Lexicon.html#nfc | Non functional change ]]
This commit is the result of modernizing the LLDB codebase by using
`nullptr` instread of `0` or `NULL`. See
https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-nullptr.html
for more information.
This is the command I ran and I to fix and format the code base:
```
run-clang-tidy.py \
-header-filter='.*' \
-checks='-*,modernize-use-nullptr' \
-fix ~/dev/llvm-project/lldb/.* \
-format \
-style LLVM \
-p ~/llvm-builds/debug-ninja-gcc
```
NOTE: There were also changes to `llvm/utils/unittest` but I did not
include them because I felt that maybe this library shall be updated in
isolation somehow.
NOTE: I know this is a rather large commit but it is a nobrainer in most
parts.
Reviewers: martong, espindola, shafik, #lldb, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: arsenm, jvesely, nhaehnle, hiraditya, JDevlieghere, teemperor, rnkovacs, emaste, kubamracek, nemanjai, ki.stfu, javed.absar, arichardson, kbarton, jrtc27, MaskRay, atanasyan, dexonsmith, arphaman, jfb, jsji, jdoerfert, lldb-commits, llvm-commits
Tags: #lldb, #llvm
Differential Revision: https://reviews.llvm.org/D61847
llvm-svn: 361484
