481 Commits

Author SHA1 Message Date
jimingham
c2b01c87dc
Make ValueObjectPrinter's handling of its ValueObject pointers more principled (NFC) (#81314)
I get a small but fairly steady stream of crash reports which I can only
explain by ValueObjectPrinter trying to access its m_valobj field, and
finding it NULL. I have never been able to reproduce any of these, and
the reports show a state too long after the fact to know what went
wrong.

I've read through this section of lldb a bunch of times trying to figure
out how this could happen, but haven't ever found anything actually
wrong that could cause this. OTOH, ValueObjectPrinter is somewhat sloppy
about how it handles the ValueObject it is printing.

a) lldb allows you to make a ValueObjectPrinter with a Null incoming
ValueObject. However, there's no affordance to set the ValueObject in
the Printer after the fact, and it doesn't really make sense to do that.
So I change the ValueObjectPrinter API's to take a ValueObject
reference, rather than a pointer. All the places that make
ValueObjectPrinters already check the non-null status of their
ValueObject's before making the ValueObjectPrinter, so sadly, I didn't
find the bug, but this will enforce the intent.
b) The next step in printing the ValueObject is deciding which of the
associated DynamicValue/SyntheticValue we are actually printing (based
on the use_dynamic and use_synthetic settings in the original
ValueObject. This was put in a pointer by GetMostSpecializedValue, but
most of the printer code just accessed the pointer, and it was hard to
reason out whether we were guaranteed to always call this before using
m_valobj. So far as I could see we always do (sigh, didn't find the bug
there either) but this was way too hard to reason about.

In fact, we figure out once which ValueObject we're going to print and
don't change that through the life of the printer. So I changed this to
both set the "most specialized value" in the constructor, and then to
always access it through GetMostSpecializedValue(). That makes it easier
to reason about the use of this ValueObject as well.

This is an NFC change, all it does is make the code easier to reason
about.
2024-02-12 15:24:11 -08:00
Dave Lee
af97edff70
[lldb] Refactor GetFormatFromCString to always check for partial matches (NFC) (#81018)
Refactors logic in `ParseInternal` that was previously calling
`GetFormatFromCString` twice, once with `partial_match_ok` set to false,
and the second time set to true.

With this change, lldb formats (ie `%@`, `%S`, etc) are checked first.
If a format is not one of those, then `GetFormatFromCString` is called
once, and now always checks for partial matches.
2024-02-08 09:32:12 -08:00
Michael Buch
d7fb94b6da
[lldb][TypeSynthetic][NFC] Make SyntheticChildrenFrontend::Update() return an enum (#80167)
This patch changes the return value of
`SyntheticChildrenFrontend::Update` to a scoped enum that aims to
describe what the return value means.
2024-02-08 11:09:45 +00:00
Dave Lee
9ff83f12fe
[lldb] Remove unnecessary FormatCache::GetEntry (NFC) (#80603)
The implementation of `FormatCache::Entry
&FormatCache::GetEntry(ConstString)` is effectively a duplication of
`std::map::operator[]`. This change deletes `GetEntry` and replaces its
use with `operator[]`.
2024-02-04 11:47:24 -08:00
Greg Clayton
dd95877958
[lldb] Make only one function that needs to be implemented when searching for types (#74786)
This patch revives the effort to get this Phabricator patch into
upstream:

https://reviews.llvm.org/D137900

This patch was accepted before in Phabricator but I found some
-gsimple-template-names issues that are fixed in this patch.

A fixed up version of the description from the original patch starts
now.

This patch started off trying to fix Module::FindFirstType() as it
sometimes didn't work. The issue was the SymbolFile plug-ins didn't do
any filtering of the matching types they produced, and they only looked
up types using the type basename. This means if you have two types with
the same basename, your type lookup can fail when only looking up a
single type. We would ask the Module::FindFirstType to lookup "Foo::Bar"
and it would ask the symbol file to find only 1 type matching the
basename "Bar", and then we would filter out any matches that didn't
match "Foo::Bar". So if the SymbolFile found "Foo::Bar" first, then it
would work, but if it found "Baz::Bar" first, it would return only that
type and it would be filtered out.

Discovering this issue lead me to think of the patch Alex Langford did a
few months ago that was done for finding functions, where he allowed
SymbolFile objects to make sure something fully matched before parsing
the debug information into an AST type and other LLDB types. So this
patch aimed to allow type lookups to also be much more efficient.

As LLDB has been developed over the years, we added more ways to to type
lookups. These functions have lots of arguments. This patch aims to make
one API that needs to be implemented that serves all previous lookups:

- Find a single type
- Find all types
- Find types in a namespace

This patch introduces a `TypeQuery` class that contains all of the state
needed to perform the lookup which is powerful enough to perform all of
the type searches that used to be in our API. It contain a vector of
CompilerContext objects that can fully or partially specify the lookup
that needs to take place.

If you just want to lookup all types with a matching basename,
regardless of the containing context, you can specify just a single
CompilerContext entry that has a name and a CompilerContextKind mask of
CompilerContextKind::AnyType.

Or you can fully specify the exact context to use when doing lookups
like: CompilerContextKind::Namespace "std"
CompilerContextKind::Class "foo"
CompilerContextKind::Typedef "size_type"

This change expands on the clang modules code that already used a
vector<CompilerContext> items, but it modifies it to work with
expression type lookups which have contexts, or user lookups where users
query for types. The clang modules type lookup is still an option that
can be enabled on the `TypeQuery` objects.

This mirrors the most recent addition of type lookups that took a
vector<CompilerContext> that allowed lookups to happen for the
expression parser in certain places.

Prior to this we had the following APIs in Module:

```
void
Module::FindTypes(ConstString type_name, bool exact_match, size_t max_matches,
                  llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
                  TypeList &types);

void
Module::FindTypes(llvm::ArrayRef<CompilerContext> pattern, LanguageSet languages,
                  llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files,
                  TypeMap &types);

void Module::FindTypesInNamespace(ConstString type_name,
                                  const CompilerDeclContext &parent_decl_ctx,
                                  size_t max_matches, TypeList &type_list);
```

The new Module API is much simpler. It gets rid of all three above
functions and replaces them with:

```
void FindTypes(const TypeQuery &query, TypeResults &results);
```
The `TypeQuery` class contains all of the needed settings:

- The vector<CompilerContext> that allow efficient lookups in the symbol
file classes since they can look at basename matches only realize fully
matching types. Before this any basename that matched was fully realized
only to be removed later by code outside of the SymbolFile layer which
could cause many types to be realized when they didn't need to.
- If the lookup is exact or not. If not exact, then the compiler context
must match the bottom most items that match the compiler context,
otherwise it must match exactly
- If the compiler context match is for clang modules or not. Clang
modules matches include a Module compiler context kind that allows types
to be matched only from certain modules and these matches are not needed
when d oing user type lookups.
- An optional list of languages to use to limit the search to only
certain languages

The `TypeResults` object contains all state required to do the lookup
and store the results:
- The max number of matches
- The set of SymbolFile objects that have already been searched
- The matching type list for any matches that are found

The benefits of this approach are:
- Simpler API, and only one API to implement in SymbolFile classes
- Replaces the FindTypesInNamespace that used a CompilerDeclContext as a
way to limit the search, but this only worked if the TypeSystem matched
the current symbol file's type system, so you couldn't use it to lookup
a type in another module
- Fixes a serious bug in our FindFirstType functions where if we were
searching for "foo::bar", and we found a "baz::bar" first, the basename
would match and we would only fetch 1 type using the basename, only to
drop it from the matching list and returning no results
2023-12-12 16:51:49 -08:00
David Spickett
68fbc8eec3 [lldb][NFC] Use UNUSED_IF_ASSERT_DISABLED instead of (void) cast
Uses of (void) remain where they are for purposes other than an
assert variable.
2023-11-03 14:20:05 +00:00
Greg Clayton
7fbd427f5e
Add the ability to get a C++ vtable ValueObject from another ValueObj… (#67599)
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
```
2023-10-30 17:46:18 -07:00
Michael Buch
0dfcfb53d7
[lldb][DataFormatter] VectorType: fix format for arrays with size not a power-of-2 (#68907)
To get the number of children for a VectorType (i.e.,
a type declared with a `vector_size`/`ext_vector_type` attribute)
LLDB previously did following calculation:
1. Get byte-size of the vector container from Clang (`getTypeInfo`).
2. Get byte-size of the element type we want to interpret the array as.
   (e.g., sometimes we want to interpret an `unsigned char vec[16]`
   as a `float32[]`).
3. `numChildren = containerSize / reinterpretedElementSize`

However, for step 1, clang will return us the *aligned* container
byte-size.
So for a type such as `float __attribute__((ext_vector_type(3)))`
(which is an array of 3 4-byte floats), clang will round up the
byte-width of the array to `16`.
(see
[here](ab6a66dbec/clang/lib/AST/ASTContext.cpp (L1987-L1992)))

This means that for vectors where the size isn't a power-of-2, LLDB
will miscalculate the number of elements.

**Solution**

This patch changes step 1 such that we calculate the container size
as `numElementsInSource * byteSizeOfElement`.
2023-10-13 20:07:41 +01:00
Walter Erquinigo
ed0a14144b
[LLDB] Fix type formatting empty c-strings (#68924)
The type formatter code is effectively considering empty strings as read
errors, which is wrong. The fix is very simple. We should rely on the
error object and stop checking the size. I also added a test.
2023-10-13 14:14:23 -04:00
Alex
140f6167b8
[lldb][NFCI] Remove typedef for TypeCategoryMap::ValueSP (#65555)
lldb already has a `ValueSP` type. This was confusing to me when reading
TypeCategoryMap, especially when `ValueSP` is not qualified. From first
glance it looks like it's referring to a
`std::shared_ptr<lldb_private::Value>` when it's really referring to a
`std::shared_ptr<lldb_private::TypeCategoryImpl>`.
2023-09-07 10:16:55 -07:00
Alex Langford
5bff905c0d [lldb][NFCI] Remove unused method TypeCategoryMap::Get(uint32_t, ValueSP &)
Differential Revision: https://reviews.llvm.org/D159387
2023-09-05 10:53:56 -07:00
walter erquinigo
79d5d9a082 [lldb] Allow synthetic providers in C++ and fix linking problems
- Allow the definition of synthetic formatters in C++ even when LLDB is built without python scripting support.
- Fix linking problems with the CXXSyntheticChildren

Differential Revision: https://reviews.llvm.org/D158010
2023-08-30 14:14:28 -04:00
Dave Lee
b43375bb81 [lldb] Add log indicating which kind of data formatter
The `formatter` logs include a function name, but these functions are mostly templates
and the template type parameter is not printed, which is useful context.

This change adds a new log which is printed upon entry of `FormatManager::Get`, which
shows the formatter context as either `format`, `summary`, or `synthetic`.

Differential Revision: https://reviews.llvm.org/D154128
2023-06-30 16:51:14 -07:00
Dave Lee
a1a74f7cde [lldb] Default can_create to true in GetChildAtIndex (NFC)
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
2023-06-13 15:51:32 -07:00
Augusto Noronha
f94c7ffe46 [lldb] Never print children if the max depth has been reached
When formatting a variable, the max depth would potentially be ignored
if the current value object failed to print itself. Change that to
always respect the max depth, even if failure occurs.

rdar://109855463

Differential Revision: https://reviews.llvm.org/D152409
2023-06-13 11:03:04 -07:00
Augusto Noronha
b1ebfc5de3 [lldb] Unconditionally increment depth when printing children
The `target.max-children-depth` setting and `--depth` flag would be
ignored if treating pointer as arrays, fix that by always incrementing
the current depth when printing a new child.

rdar://109855463

Differential Revision: https://reviews.llvm.org/D151950
2023-06-08 13:30:30 -07:00
Fangrui Song
65ceb42d63 Replace deprecated startswith_insensitive with starts_with_insensitive 2023-06-05 11:01:27 -07:00
Dave Lee
c7eb1b0747 [lldb] Consult summary provider before printing children of root references
When printing the root of a value, if it's a reference its children are unconditionally
printed - in contrast to pointers whose children are only printed if a sufficient
pointer depth is given.

However, the children are printed even when there's a summary provider that says not to.
If a summary provider exists, this change consults it to determine if children should be
printed.

For example, given a variable of type `std::string &`, this change has the following
effect:

Before:

```
(lldb) p string_ref
(std::string &) string_ref = "one two three four five six seven eight nine ten": {
  __r_ = {
    std::__1::__compressed_pair_elem<std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__rep, 0, false> = {
      __value_ = {
         = {
          __l = (__data_ = "one two three four five six seven eight nine ten", __size_ = 48, __cap_ = 64, __is_long_ = 1)
          __s = (__data_ = "@\0p\U00000001\0`\0\00\0\0\0\0\0\0\0@", __padding_ = "\x80t<", __size_ = '\0', __is_long_ = '\x01')
          __r = {
            __words ={...}
          }
        }
      }
    }
  }
}
```

After:

```
(lldb) p string_ref
(std::string &) string_ref = "one two three four five six seven eight nine ten"
```

rdar://73248786

Differential Revision: https://reviews.llvm.org/D151748
2023-05-30 15:35:03 -07:00
Dave Lee
8d4f0e0795 [lldb] Refine call to decl printing helper (NFC)
When `ValueObjectPrinter` calls its `m_decl_printing_helper`, not all state is passed to
the helper. In particular, the helper doesn't have access to `m_curr_depth`, and thus
can't act on the logic within `ShouldShowName`.

To address this, this change passes in a modified copy of `m_options`. The modified copy
has has `m_hide_name` set according to the results of `ShouldShowName`. This allows
helper functions to know whether the name should be shown or hidden, without having
access to `ValueObjectPrinter`'s full state.

This is NFC in mainline lldb, as the only decl printing helper doesn't make use of this.
However in swift-lldb at least, there are decl printing helpers that do need this
information passed to them. See https://github.com/apple/llvm-project/pull/6795 where a
test is also included.

Differential Revision: https://reviews.llvm.org/D150129
2023-05-15 15:20:48 -07:00
Jorge Gorbe Moya
d69518b4e5 Re-land "[lldb] Make the libcxx unique_ptr prettyprinter support custom deleters."
This reverts commit 45351120105a7257ccb1e38ec1b1f8a452269da2.
2023-05-01 16:19:01 -07:00
Jorge Gorbe Moya
4535112010 Revert "[lldb] Make the libcxx unique_ptr prettyprinter support custom deleters."
This reverts commit d366da97bd24ddfb91c9f260fa0aaf105d947652.
2023-05-01 14:14:09 -07:00
Jorge Gorbe Moya
d366da97bd [lldb] Make the libcxx unique_ptr prettyprinter support custom deleters.
The unique_ptr prettyprinter calls `GetValueOfLibCXXCompressedPair`,
which looks for a `__value_` child. However, when the second value in
the compressed pair is not an empty class, there are two `__value_`
children because `__compressed_pair` derives twice from
`__compressed_pair_elem`, one for each member of the pair. And then the
lookup fails because it's ambiguous.

This patch makes the following changes:

- Rename `GetValueOfLibCXXCompressedPair` to
  `GetFirstValueOfLibCXXCompressedPair`, and add a similar function to
  get the second value. Put both functions in
  Plugin/Language/CPlusPlus/LibCxx.cpp because it seems inappropriate to
  have libcxx-specific helpers separate from all the libcxx-dependent
  code.

- Read the second value of the `__ptr_` pair and display a "deleter"
  child in the unique_ptr synthetic child provider, when available.

- Add a test case for the non-empty deleter case.

Differential Revision: https://reviews.llvm.org/D148662
2023-05-01 13:08:04 -07:00
David Spickett
e07a421dd5 [lldb] Show register fields using bitfield struct types
This change uses the information from target.xml sent by
the GDB stub to produce C types that we can use to print
register fields.

lldb-server *does not* produce this information yet. This will
only work with GDB stubs that do. gdbserver or qemu
are 2 I know of. Testing is added that uses a mocked lldb-server.
```
(lldb) register read cpsr x0 fpcr fpsr x1
    cpsr = 0x60001000
         = (N = 0, Z = 1, C = 1, V = 0, TCO = 0, DIT = 0, UAO = 0, PAN = 0, SS = 0, IL = 0, SSBS = 1, BTYPE = 0, D = 0, A = 0, I = 0, F = 0, nRW = 0, EL = 0, SP = 0)
```

Only "register read" will display fields, and only when
we are not printing a register block.

For example, cpsr is a 32 bit register. Using the target's scratch type
system we construct a type:
```
struct __attribute__((__packed__)) cpsr {
  uint32_t N : 1;
  uint32_t Z : 1;
  ...
  uint32_t EL : 2;
  uint32_t SP : 1;
};
```

If this register had unallocated bits in it, those would
have been filled in by RegisterFlags as anonymous fields.
A new option "SetChildPrintingDecider" is added so we
can disable printing those.

Important things about this type:
* It is packed so that sizeof(struct cpsr) == sizeof(the real register).
  (this will hold for all flags types we create)
* Each field has the same storage type, which is the same as the type
  of the raw register value. This prevents fields being spilt over
  into more storage units, as is allowed by most ABIs.
* Each bitfield size matches that of its register field.
* The most significant field is first.

The last point is required because the most significant bit (MSB)
being on the left/top of a print out matches what you'd expect to
see in an architecture manual. In addition, having lldb print a
different field order on big/little endian hosts is not acceptable.

As a consequence, if the target is little endian we have to
reverse the order of the fields in the value. The value of each field
remains the same. For example 0b01 doesn't become 0b10, it just shifts
up or down.

This is needed because clang's type system assumes that for a struct
like the one above, the least significant bit (LSB) will be first
for a little endian target. We need the MSB to be first.

Finally, if lldb's host is a different endian to the target we have
to byte swap the host endian value to match the endian of the target's
typesystem.

| Host Endian | Target Endian | Field Order Swap | Byte Order Swap |
|-------------|---------------|------------------|-----------------|
| Little      | Little        | Yes              | No              |
| Big         | Little        | Yes              | Yes             |
| Little      | Big           | No               | Yes             |
| Big         | Big           | No               | No              |

Testing was done as follows:
* Little -> Little
  * LE AArch64 native debug.
* Big -> Little
  * s390x lldb running under QEMU, connected to LE AArch64 target.
* Little -> Big
  * LE AArch64 lldb connected to QEMU's GDB stub, which is running
    an s390x program.
* Big -> Big
 * s390x lldb running under QEMU, connected to another QEMU's GDB
   stub, which is running an s390x program.

As we are not allowed to link core code to plugins directly,
I have added a new plugin RegisterTypeBuilder. There is one implementation
of this, RegisterTypeBuilderClang, which uses TypeSystemClang to build
the CompilerType from the register fields.

Reviewed By: jasonmolenda

Differential Revision: https://reviews.llvm.org/D145580
2023-04-13 13:04:34 +00:00
Alex Langford
0e22b8cba7 [lldb] Change formatter helper function parameter list to remove ConstString
All of these functions take a ConstString for the type_name,
but this isn't really needed for two reasons:
1.) This parameter is always constructed from a static c-string
  constant.
2.) They are passed along to to `AddTypeSummary` as a StringRef anyway.

Differential Revision: https://reviews.llvm.org/D148050
2023-04-12 11:20:24 -07:00
Dave Lee
d03d98b71d [lldb] Replace sprintf with snprintf (NFC)
On macOS, `sprintf` is deprecated, using `snprintf` is recommended instead.

Differential Revision: https://reviews.llvm.org/D147246
2023-03-30 12:29:05 -07:00
Dave Lee
51dd8a20c1 [lldb] Fix value printing for a specific case
Fixes printing of spaces in cases where the following are true:

  1. Persistent results are disabled
  2. The type has a summary string

As reported by @jgorbe in D146783, two spaces were being printed before the summary
string, and no spaces were printed after.

Differential Revision: https://reviews.llvm.org/D147006
2023-03-28 09:38:46 -07:00
Dave Lee
23349d83a9 [lldb] Add ability to hide the root name of a value
When printing a value, allow the root value's name to be elided, without omiting the
names of child values.

At the API level, this adds `SetHideRootName()`, which joins the existing
`SetHideName()` function.

This functionality is used by `dwim-print` and `expression`.

Fixes an issue identified by @jgorbe in https://reviews.llvm.org/D145609.

Differential Revision: https://reviews.llvm.org/D146783
2023-03-24 14:07:31 -07:00
Alex Langford
5499b026d2 [lldb][CMake] Enforce not linking against plugin libs in core libs
Non-plugin lldb libraries should generally not be linking against lldb
plugin libraries. Enforce this in CMake.

Differential Revision: https://reviews.llvm.org/D146553
2023-03-21 16:24:36 -07:00
Jason Molenda
7e770f9c17 Revert "Add SBValue::GetValueAsAddress API for removing non-addressing metadata"
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.
2023-03-02 14:36:37 -08:00
Jason Molenda
4d635be2db Add SBValue::GetValueAsAddress API for removing non-addressing metadata
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
2023-03-02 13:32:37 -08:00
Jim Ingham
e8a2fd5e7b An SBValue whose underlying ValueObject has no valid value, but does
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
2023-02-28 16:41:20 -08:00
Dave Lee
63c77bf71d [lldb] Make persisting result variables configurable
Context: The `expression` command uses artificial variables to store the expression
result. This result variable is unconditionally kept around after the expression command
has completed. These variables are known as persistent results. These are the variables
`$0`, `$1`, etc, that are displayed when running `p` or `expression`.

This change allows users to control whether result variables are persisted, by
introducing a `--persistent-result` flag.

This change keeps the current default behavior, persistent results are created by
default. This change gives users the ability to opt-out by re-aliasing `p`. For example:

```
command unalias p
command alias p expression --persistent-result false --
```

For consistency, this flag is also adopted by `dwim-print`. Of note, if asked,
`dwim-print` will create a persistent result even for frame variables.

Differential Revision: https://reviews.llvm.org/D144230
2023-02-17 17:50:43 -08:00
Kazu Hirata
2fe8327406 [lldb] Use std::optional instead of llvm::Optional (NFC)
This patch replaces (llvm::|)Optional< with std::optional<.  I'll post
a separate patch to clean up the "using" declarations, #include
"llvm/ADT/Optional.h", etc.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2023-01-07 14:18:35 -08:00
Kazu Hirata
f190ce625a [lldb] Add #include <optional> (NFC)
This patch adds #include <optional> to those files containing
llvm::Optional<...> or Optional<...>.

I'll post a separate patch to actually replace llvm::Optional with
std::optional.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2023-01-07 13:43:00 -08:00
Adrian Prantl
6eaedbb52f Make CompilerType safe
When a process gets restarted TypeSystem objects associated with it
may get deleted, and any CompilerType objects holding on to a
reference to that type system are a use-after-free in waiting. Because
of the SBAPI, we don't have tight control over where CompilerTypes go
and when they are used. This is particularly a problem in the Swift
plugin, where the scratch TypeSystem can be restarted while the
process is still running. The Swift plugin has a lock to prevent
abuse, but where there's a lock there can be bugs.

This patch changes CompilerType to store a std::weak_ptr<TypeSystem>.
Most of the std::weak_ptr<TypeSystem>* uglyness is hidden by
introducing a wrapper class CompilerType::WrappedTypeSystem that has a
dyn_cast_or_null() method. The only sites that need to know about the
weak pointer implementation detail are the ones that deal with
creating TypeSystems.

rdar://101505232

Differential Revision: https://reviews.llvm.org/D136650
2022-11-16 15:51:26 -08:00
Jorge Gorbe Moya
d76566417e [lldb] Add matching based on Python callbacks for data formatters.
This patch adds a new matching method for data formatters, in addition
to the existing exact typename and regex-based matching. The new method
allows users to specify the name of a Python callback function that
takes a `SBType` object and decides whether the type is a match or not.

Here is an overview of the changes performed:

- Add a new `eFormatterMatchCallback` matching type, and logic to handle
  it in `TypeMatcher` and `SBTypeNameSpecifier`.

- Extend `FormattersMatchCandidate` instances with a pointer to the
  current `ScriptInterpreter` and the `TypeImpl` corresponding to the
  candidate type, so we can run registered callbacks and pass the type
  to them. All matcher search functions now receive a
  `FormattersMatchCandidate` instead of a type name.

- Add some glue code to ScriptInterpreterPython and the SWIG bindings to
  allow calling a formatter matching callback. Most of this code is
  modeled after the equivalent code for watchpoint callback functions.

- Add an API test for the new callback-based matching feature.

For more context, please check the RFC thread where this feature was
originally discussed:
https://discourse.llvm.org/t/rfc-python-callback-for-data-formatters-type-matching/64204/11

Differential Revision: https://reviews.llvm.org/D135648
2022-10-19 12:53:38 -07:00
Jorge Gorbe Moya
e5fd507f9b [NFCI] More TypeCategoryImpl refactoring.
The main aim of this patch is to delete the remaining instances of code
reaching into the internals of `TypeCategoryImpl`. I made the following
changes:

- Add some more methods to `TieredFormatterContainer` and
  `TypeCategoryImpl` to expose functionality that is implemented in
  `FormattersContainer`.

- Add new overloads of `TypeCategoryImpl::AddTypeXXX` to make it easier
  to add formatters to categories without reaching into the internal
  `FormattersContainer` objects.

- Remove the `GetTypeXXXContainer` and `GetRegexTypeXXXContainer`
  accessors from `TypeCategoryImpl` and update all call sites to use the
  new methods instead.

Differential Revision: https://reviews.llvm.org/D135399
2022-10-10 15:14:55 -07:00
Jorge Gorbe Moya
1f2a21820d [NFCI] Refactor FormatterContainerPair into TieredFormatterContainer.
`FormatterContainerPair` is (as its name indicates) a very thin wrapper
over two formatter containers, one for exact matches and another one for
regex matches. The logic to decide which subcontainer to access is
replicated everywhere `FormatterContainerPair`s are used.

So, for example, when we look for a formatter there's some adhoc code
that does a lookup in the exact match formatter container, and if it
fails it does a lookup in the regex match formatter container. The same
logic is then copied and pasted for summaries, filters, and synthetic
child providers.

This change introduces a new `TieredFormatterContainer` that has two
main characteristics:

- It generalizes `FormatterContainerPair` from 2 to any number of
  subcontainers, that are looked up in priority order.
- It centralizes all the logic to choose which subcontainer to use for
  lookups, add/delete, and indexing.

This allows us to have a single copy of the same logic, templatized for
each kind of formatter. It also simplifies the upcoming addition of a
new tier of callback-based matches. See
https://discourse.llvm.org/t/rfc-python-callback-for-data-formatters-type-matching/64204
for more details about this.

The rest of the change is mostly replacing copy-pasted code with calls
to methods of the relevant `TieredFormatterContainer`, and adding some
methods to the `TypeCategoryImpl` class so we can remove some of this
copy-pasted code from `SBTypeCategory`.

Differential Revision: https://reviews.llvm.org/D133910
2022-09-27 14:28:41 -07:00
Jorge Gorbe Moya
dce6887336 [NFCI] Clean up enum FormatCategoryItem.
- Merge pairs like `eFormatCategoryItemSummary` and
  `eFormatCategoryItemRegexSummary` into a single value. See explanation
  below.

- Rename `eFormatCategoryItemValue` to `eFormatCategoryItemFormat`. This
  makes the enum match the names used elsewhere for formatter kinds
  (format, summary, filter, synth).

- Delete unused values `eFormatCategoryItemValidator` and
  `eFormatCategoryItemRegexValidator`.

This enum is only used to reuse some code in CommandObjectType.cpp.  For
example, instead of having separate implementations for `type summary
delete`, `type format delete`, and so on, there's a single generic
implementation that takes an enum value, and then the specific commands
derive from it and set the right flags for the specific kind of
formatter.

Even though the enum distinguishes between regular and regex matches for
every kind of formatter, this distinction is never used: enum values are
always specified in pairs like
`eFormatCategoryItemSummary | eFormatCategoryItemRegexSummary`.

This causes some ugly code duplication in TypeCategory.cpp. In order to
handle every flag combination some code appears 8 times:

{format, summary, synth, filter} x {exact, regex}

Differential Revision: https://reviews.llvm.org/D134244
2022-09-20 10:41:06 -07:00
Joe Loser
47b76631e7 [lldb] Use std::size instead of llvm::array_lengthof
LLVM contains a helpful function for getting the size of a C-style
array: `llvm::array_lengthof`. This is useful prior to C++17, but not as
helpful for C++17 or later: `std::size` already has support for C-style
arrays.

Change call sites to use `std::size` instead.

Differential Revision: https://reviews.llvm.org/D133501
2022-09-08 14:21:55 -06:00
Jorge Gorbe Moya
fe01292457 Move FormattersMatchCandidate flags to a struct.
This removes some error-prone repetition in
FormatManager::GetPossibleMatches, where the same three boolean flags
are passed in a row multiple times as arguments to recursive calls to
GetPossibleMatches.

Instead of:
```
  // same flags, but with did_strip_typedef set to true.
  GetPossibleMatches(..., did_strip_ptr, did_strip_ref, true);
```
we can now say
```
  GetPossibleMatches(..., current_flags.WithStrippedTypedef());
```
which hopefully makes the intent clearer, and more readable in case we
add another flag.

Reviewed by: DavidSpickett, labath

Differential Revision: https://reviews.llvm.org/D131459
2022-08-09 10:48:49 -07:00
Dave Lee
2f9fc576be [lldb] Add setting for max depth of value object printing (NFC)
This adds a setting (`target.max-children-depth`) that will provide a default value for the `--depth` flag used by `expression` and `frame variable`.

The new setting uses the same default that's currently fixed in source: `UINT32_MAX`.

This provides two purposes:

1. Allowing downstream forks to provide a customized default.
2. Allowing users to set their own default.

Following `target.max-children-count`, a warning is emitted when the max depth is reached. The warning lets users know which flags or settings they can customize. This warning is shown only when the limit is the default value.

rdar://87466495

Differential Revision: https://reviews.llvm.org/D123954
2022-05-03 10:39:42 -07:00
Jonas Devlieghere
fc54427e76
[lldb] Refactor DataBuffer so we can map files as read-only
Currently, all data buffers are assumed to be writable. This is a
problem on macOS where it's not allowed to load unsigned binaries in
memory as writable. To be more precise, MAP_RESILIENT_CODESIGN and
MAP_RESILIENT_MEDIA need to be set for mapped (unsigned) binaries on our
platform.

Binaries are mapped through FileSystem::CreateDataBuffer which returns a
DataBufferLLVM. The latter is backed by a llvm::WritableMemoryBuffer
because every DataBuffer in LLDB is considered to be writable. In order
to use a read-only llvm::MemoryBuffer I had to split our abstraction
around it.

This patch distinguishes between a DataBuffer (read-only) and
WritableDataBuffer (read-write) and updates LLDB to use the appropriate
one.

rdar://74890607

Differential revision: https://reviews.llvm.org/D122856
2022-04-05 13:46:37 -07:00
Pavel Labath
13a3b0bb4b [lldb] Remove usages of case-insensitive c-string functions
They are not portable (which meant we had a hand-rolled implementation
for windows), and llvm::StringRef provides equivalent functionality.
2022-03-29 17:59:17 +02:00
Shafik Yaghmour
28c878aeb2 [LLDB] Applying clang-tidy modernize-use-default-member-init over LLDB
Applied modernize-use-default-member-init clang-tidy check over LLDB.
It appears in many files we had already switched to in class member init but
never updated the constructors to reflect that. This check is already present in
the lldb/.clang-tidy config.

Differential Revision: https://reviews.llvm.org/D121481
2022-03-14 13:32:03 -07:00
Pavel Labath
c34698a811 [lldb] Rename Logging.h to LLDBLog.h and clean up includes
Most of our code was including Log.h even though that is not where the
"lldb" log channel is defined (Log.h defines the generic logging
infrastructure). This worked because Log.h included Logging.h, even
though it should.

After the recent refactor, it became impossible the two files include
each other in this direction (the opposite inclusion is needed), so this
patch removes the workaround that was put in place and cleans up all
files to include the right thing. It also renames the file to LLDBLog to
better reflect its purpose.
2022-02-03 14:47:01 +01:00
Pavel Labath
a007a6d844 [lldb] Convert "LLDB" log channel to the new API 2022-02-02 14:13:08 +01:00
Benjamin Kramer
f15014ff54 Revert "Rename llvm::array_lengthof into llvm::size to match std::size from C++17"
This reverts commit ef8206320769ad31422a803a0d6de6077fd231d2.

- It conflicts with the existing llvm::size in STLExtras, which will now
  never be called.
- Calling it without llvm:: breaks C++17 compat
2022-01-26 16:55:53 +01:00
serge-sans-paille
ef82063207 Rename llvm::array_lengthof into llvm::size to match std::size from C++17
As a conquence move llvm::array_lengthof from STLExtras.h to
STLForwardCompat.h (which is included by STLExtras.h so no build
breakage expected).
2022-01-26 16:17:45 +01:00
Pavel Labath
31c7165a2b [lldb] Remove summary for signed char *
It conflicts with the summary for BOOL * (aka signed char *). This
partially reverts D112709.
2022-01-06 19:52:24 +01:00