Commit Graph

2011 Commits

Author SHA1 Message Date
Med Ismail Bennani
e8966125e2 [lldb/Commands] Fix disk completion from root directory
This patch should fix path completion starting from the root directory.

To do so, this patch adds a special case when setting the search
directory when the completion buffer points to the root directory.

Differential Revision: https://reviews.llvm.org/D152013

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-06-06 10:58:34 -07:00
Med Ismail Bennani
6a9c3e6115 [lldb/Commands] Add support to auto-completion for user commands
This patch should allow the user to set specific auto-completion type
for their custom commands.

To do so, we had to hoist the `CompletionType` enum so the user can
access it and add a new completion type flag to the CommandScriptAdd
Command Object.

So now, the user can specify which completion type will be used with
their custom command, when they register it.

This also makes the `crashlog` custom commands use disk-file completion
type, to browse through the user file system and load the report.

Differential Revision: https://reviews.llvm.org/D152011

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-06-06 10:58:34 -07:00
Med Ismail Bennani
1e82b20118 [lldb/Target] Add ability to set a label to targets
This patch add the ability for the user to set a label for a target.

This can be very useful when debugging targets with the same executables
in the same session.

Labels can be set either at the target creation in the command
interpreter or at any time using the SBAPI.

Target labels show up in the `target list` output, following the target
index, and they also allow the user to switch targets using them.

rdar://105016191

Differential Revision: https://reviews.llvm.org/D151859

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-06-06 10:58:34 -07:00
Dave Lee
061a839033 [lldb] Prevent dwim-print from showing kNoResult error
Expression evaluation for `void` valued expressions sets an error using the `kNoResult`
code. Like the `expression` command, `dwim-print` should also not print such errors.

Before:

```
(lldb) dwim-print (void)printf("hi\n")
hi
Error: 'unknown error'
```

After:

```
(lldb) dwim-print (void)printf("hi\n")
hi
```

rdar://109746544

Differential Revision: https://reviews.llvm.org/D151351
2023-05-30 15:38:42 -07:00
Jason Molenda
f32d24d577 Revert "[lldb] Disable variable watchpoints when going out of scope"
Reverting https://reviews.llvm.org/D151366 until Ismail has a chance
to look at the ubuntu CI test failures and can reland.

This reverts commit 7c847ac4bd.
2023-05-26 15:32:10 -07:00
Med Ismail Bennani
7c847ac4bd [lldb] Disable variable watchpoints when going out of scope
If we use a variable watchpoint with a condition using a scope variable,
if we go out-of-scope, the watpoint remains active which can the
expression evaluator to fail to parse the watchpoint condition (because
of the missing varible bindings).

This was discovered after `watchpoint_callback.test` started failing on
the green dragon bot.

This patch should address that issue by setting an internal breakpoint
on the return addresss of the current frame when creating a variable
watchpoint. The breakpoint has a callback that will disable the watchpoint
if the the breakpoint execution context matches the watchpoint execution
context.

This is only enabled for local variables.

This patch also re-enables the failing test following e1086384e5.

rdar://109574319

Differential Revision: https://reviews.llvm.org/D151366

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2023-05-25 15:07:09 -07:00
Dave Lee
db81455213 [lldb] Delay removal of persistent results
Follow up to "Suppress persistent result when running po" (D144044).

This change delays removal of the persistent result until after `Dump` has been called.
In doing so, the persistent result is available for the purpose of getting its object
description.

In the original change, the persistent result removal happens indirectly, by setting
`EvaluateExpressionOptions::SetSuppressPersistentResult`. In practice this has worked,
however this exposed a latent bug in swift-lldb. The subtlety, and the bug, depend on
when the persisteted result variable is removed.

When the result is removed via `SetSuppressPersistentResult`, it happens within the call
to `Target::EvaluateExpression`. That is, by the time the call returns, the persistent
result is already removed.

The issue occurs shortly thereafter, when `ValueObject::Dump` is called, it cannot make
use of the persistent result variable (instead it uses the `ValueObjectConstResult`). In
swift-lldb, this causes an additional expression evaluation to happen. It first tries an
expression that reference `$R0` etc, but that always fails because `$R0` is removed. The
fallback to this failure does work most of the time, but there's at least one bug
involving imported Clang types.

Differential Revision: https://reviews.llvm.org/D150619
2023-05-18 09:44:11 -07:00
Jonas Devlieghere
3ebb33632a [lldb] Complete OptionValue cleanup (NFC)
Make the `Get.*Value` and `Set.*Value` function private and migrate the
last remaining call sites to the new overloaded/templated functions.
2023-05-14 20:18:47 -07:00
Jim Ingham
e19387e693 We can't let GetStackFrameCount get interrupted or it will give the
wrong answer. Plus, it's useful in some places to have a way to force
the full stack to be created even in the face of
interruption. Moreover, most of the time when you're just getting
frames, you don't need to know the number of frames in the stack to
start with. You just keep calling
Thread::GetStackFrameAtIndex(index++) and when you get a null
StackFrameSP back, you're done. That's also more amenable to
interruption if you are doing some work frame by frame.

So this patch makes GetStackFrameCount always return the full count,
suspending interruption. I also went through all the places that use
GetStackFrameCount to make sure that they really needed the full stack
walk. In many cases, they did not. For instance frame select -r 10 was
getting the number of frames just to check whether cur_frame_idx + 10
was within the stack. It's better in that case to see if that frame
exists first, since that doesn't force a full stack walk, and only
deal with walking off the end of the stack if it doesn't...

I also added a test for some of these behaviors.

Differential Revision: https://reviews.llvm.org/D150236
2023-05-11 14:48:54 -07:00
Kazu Hirata
e6b52355a1 [lldb] Replace None with std::nullopt in comments (NFC)
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
2023-05-06 08:56:24 -07:00
Alex Langford
e9eaf7b430 Re-land "[lldb] Expose a const iterator for SymbolContextList"
Re-lands 04aa943be8 with modifications
to fix tests.
I originally reverted this because it caused a test to fail on Linux.
The problem was that I inverted a condition on accident.
2023-05-05 11:19:21 -07:00
Jonas Devlieghere
917b3a7e62 [lldb] Move Core/FileSpecList -> Utility/FileSpecList (NFC)
There's no reason for FileSpecList to live in lldb/Core while FileSpec
lives in lldb/Utility. Move FileSpecList next to FileSpec.
2023-05-04 22:00:17 -07:00
Alex Langford
3d6073a9c3 Revert "[lldb] Expose a const iterator for SymbolContextList"
This reverts commit 04aa943be8.

This broke the debian buildbot and I'm not sure why. Reverting so I can
investigate.
2023-05-04 16:49:30 -07:00
Alex Langford
04aa943be8 [lldb] Expose a const iterator for SymbolContextList
There are many situations where we'll iterate over a SymbolContextList
with the pattern:
```
SymbolContextList sc_list;
// Fill in sc_list here
for (auto i = 0; i < sc_list.GetSize(); i++) {
  SymbolContext sc;
  sc_list.GetSymbolAtContext(i, sc);

  // Do work with sc
}
```
Adding an iterator to iterate over the instances directly means we don't
have to do bounds checking or create a copy of every element of the
SymbolContextList.

Differential Revision: https://reviews.llvm.org/D149900
2023-05-04 16:36:44 -07:00
Alex Langford
50e79d725c [lldb] Minor cleanups at callsites of FileSpec::GetFileNameExtension
FileSpec::GetFileNameExtension returns a StringRef. In some cases we
are calling it and then storing the result in a local. To prevent
cases where we store the StringRef, mutate the Filespec, and then try to
use the stored StringRef afterwards, I've audited the callsites and made
adjustments to mitigate: Either marking the FileSpec it comes from as
const (to avoid mutations) or by not storing the StringRef in a local if
it makes sense not to.

Differential Revision: https://reviews.llvm.org/D149671
2023-05-02 17:20:29 -07:00
Jonas Devlieghere
ddd9358bca [lldb] Remove unused will_modify argument (NFC)
Various OptionValue related classes are passing around will_modify but
the value is never used. This patch simplifies the interfaces by
removing the redundant argument.
2023-05-02 00:20:34 -07:00
Jonas Devlieghere
fe3ee68074 [lldb] Fix warning: extra ';' outside of a function is incompatible with C++98
Fix warning, remove trailing whitespace and fix formatting.
2023-05-01 21:23:47 -07:00
Jonas Devlieghere
9cb3af1e86 [lldb] Fix bug introduced by fdbe7c7faa
I didn't account for the scenario where the string was set but was
empty. This commit restores the old behavior and fixes
TestMemoryFind.py.
2023-05-01 21:23:14 -07:00
Jonas Devlieghere
fdbe7c7faa [lldb] Refactor OptionValue to return a std::optional (NFC)
Refactor OptionValue to return a std::optional instead of taking a fail
value. This allows the caller to handle situations where there's no
value, instead of being unable to distinguish between the absence of a
value and the value happening the match the fail value. When a fail
value is required, std::optional::value_or() provides the same
functionality.
2023-05-01 21:08:23 -07:00
Jim Ingham
930c8ac5f5 Improve the help output for type XXX delete where XXX is summary, format,
etc...

Differential Revision: https://reviews.llvm.org/D148282
2023-05-01 14:21:27 -07:00
Alex Langford
6fcdfc378c [lldb] Change return type of FileSpec::GetFileNameExtension
These don't really need to be in ConstStrings. It's nice that comparing
ConstStrings is fast (just a pointer comparison) but the cost of
creating the ConstString usually already includes the cost of doing a
StringRef comparison anyway, so this is just extra work and extra memory
consumption for basically no benefit.

Differential Revision: https://reviews.llvm.org/D149300
2023-04-26 15:56:29 -07:00
Alex Langford
c997acb97a [lldb] Add support for specifying language when setting watchpoint by expression
This is useful in contexts where you have multiple languages in play:
You may be stopped in a frame for language A, but want to set a watchpoint
with an expression using language B. The current way to do this is to
use the setting `target.language` while setting the watchpoint and
unset it after the watchpoint is set, but that's kind of clunky and
somewhat error-prone. This should add a better way to do this.

rdar://108202559

Differential Revision: https://reviews.llvm.org/D149111
2023-04-26 10:24:28 -07:00
Jim Ingham
076341d108 Make sure SelectMostRelevantFrame happens only when returning to the user.
This is a user facing action, it is meant to focus the user's attention on
something other than the 0th frame when you stop somewhere where that's
helpful. For instance, stopping in pthread_kill after an assert will select
the assert frame.

This is not something you want to have happen internally in lldb, both
because internally you really don't want the selected frame changing out
from under you, and because the recognizers can do arbitrary work, and that
can cause deadlocks or other unexpected behavior.

However, it's not something that the current code does
explicitly after a stop has been delivered, it's expected to happen implicitly
as part of stopping. I changing this to call SMRF explicitly after a user
stop, but that got pretty ugly quickly.

So I added a bool to control whether to run this and audited all the current
uses to determine whether we're returning to the user or not.

Differential Revision: https://reviews.llvm.org/D148863
2023-04-21 14:21:25 -07:00
David Spickett
c9083bea16 [LLDB] Don't print register fields when asked for a specific format
Previously if a register had fields we would always print them after the
value if the register was asked for by name.
```
(lldb) register read MDCR_EL3
MDCR_EL3 = 0x00000000
         = {
             ETBAD = 0
<...>
             RLTE = 0
           }
```
This can be quite annoying if there are a whole lot of fields but you
want to see the register in a specific format.
```
(lldb) register read MDCR_EL3 -f i
MDCR_EL3 = 0x00000000   unknown     udf    #0x0
         = {
             ETBAD = 0
<...lots of fields...>
```
Since it pushes the interesting bit far up the terminal. To solve this,
don't print fields if the user passes --format. If they're doing that
then I think it's reasonable to assume they know what they want and only
want to see that output.

This also gives users a way to silence fields, but not change the format.
By doing `register read foo -f x`. In case they are not useful or perhaps
they are trying to work around a crash.

I have customised the help text for --format for register read to explain this:
```
-f <format> ( --format <format> )
     Specify a format to be used for display. If this is set, register fields will not be dispayed.
```

Reviewed By: jasonmolenda

Differential Revision: https://reviews.llvm.org/D148790
2023-04-21 11:47:05 +00:00
David Spickett
2ad771cf7b [lldb] Change some pointers to refs in register printing code
No one was passing nullptr for these.

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D148228
2023-04-17 07:40:13 +00:00
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
Mariya Podchishchaeva
42ae055b4c [NFC] Fix potential for use-after-free in DumpModuleInfoAction
Since each `DumpModuleInfoAction` can now contain a pointer to a
`raw_ostream`, saving there a poiter that owned by a local `unique_ptr`
may cause use-after-free. Clarify ownership and save a `shared_ptr`
inside of `DumpModuleInfoAction` instead.
Found by static analyzer.

Reviewed By: tahonermann, aaron.ballman

Differential Revision: https://reviews.llvm.org/D146412
2023-03-30 06:44:23 -04:00
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
Dave Lee
abddb83598 [lldb] Fix type of --apply-fixits (NFC) 2023-03-23 22:49:29 -07:00
Arthur Eubanks
088da8a0e5 [lldb][NFC] makeArrayRef -> ArrayRef
makeArrayRef is deprecated.
2023-03-23 14:05:06 -07:00
Dave Lee
4d18d97b59 [lldb] Fix dwim-print error message for missing expr 2023-03-22 14:25:32 -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
Dave Lee
3854963854 Recommit [lldb] Change dwim-print to default to disabled persistent results
Change `dwim-print` to now disable persistent results by default, unless requested by
the user with the `--persistent-result` flag.

Ex:

```
(lldb) dwim-print 1 + 1
(int) 2
(lldb) dwim-print --persistent-result on -- 1 + 1
(int) $0 = 2
```

Users who wish to enable persistent results can make and use an alias that includes
`--persistent-result on`.

Updates: To recommit this, both TestPersistentResult.py and TestPAlias.py needed to be
updated, as well as the changes in D146230.

Differential Revision: https://reviews.llvm.org/D145609
2023-03-21 10:42:24 -07:00
Jonas Devlieghere
147b609640 [lldb] Unify WatchpointSP variable names (NFC)
LLDB uses `_up`, `_sp` and `_wp` suffixes for unique, shared and weak
pointers respectively. This can become confusing in combination with
watchpoints which are commonly abbreviated to `wp`. Update
CommandObjectWatchpoint to use `watch_sp` for all `WatchpointSP`
variables.
2023-03-17 10:09:40 -07:00
Jonas Devlieghere
2a76429778 [lldb] Set the watchpoint spec for expression watchpoints
When setting a variable watchpoint, the watchpoint stores the variable
name in the watchpoint spec. For expression variables we should store
the expression in the watchpoint spec. This patch adds that
functionality.

rdar://106096860

Differential revision: https://reviews.llvm.org/D146262
2023-03-17 09:55:57 -07:00
Jim Ingham
fe61b38258 Add a Debugger interruption mechanism in conjunction with the
Command Interpreter mechanism.

Differential Revision: https://reviews.llvm.org/D145136
2023-03-15 16:45:14 -07:00
Dave Lee
9e6a65f52c Revert "[lldb] Change dwim-print to default to disabled persistent results"
This reverts commit 8bad4ae679.
2023-03-15 14:00:00 -07:00
Dave Lee
8bad4ae679 [lldb] Change dwim-print to default to disabled persistent results
Change `dwim-print` to now disable persistent results by default, unless requested by
the user with the `--persistent-result` flag.

Ex:

```
(lldb) dwim-print 1 + 1
(int) 2
(lldb) dwim-print --persistent-result on -- 1 + 1
(int) $0 = 2
```

Users who wish to enable persistent results can make and use an alias that includes
`--persistent-result on`.

Differential Revision: https://reviews.llvm.org/D145609
2023-03-15 13:34:19 -07:00
Dave Lee
5e0ee1b395 [lldb] Make repeat commands work for regex commands
Fix logic for repeat commands, so that regex commands (specificially `bt`) are
given the opportunity to provide a repeat command.

rdar://104562616

Differential Revision: https://reviews.llvm.org/D143695
2023-03-08 16:21:42 -08:00
Augusto Noronha
581ac50d58 [lldb] Only replace valobj with persisted one if not null in DWIMPrint
Differential Revision: https://reviews.llvm.org/D145612
2023-03-08 14:18:40 -08:00
Med Ismail Bennani
601583e5a3 [lldb/Utility] Fix layering violation caused by ScriptedMetadata
This patch moves `ScriptedMetadata.h` from the `Interpreter` directory to
the `Utility` sub-directory since `ProcessInfo.h` depends on it.

It also gets rid of the unused `OptionGroupPythonClassWithDict`
constructor for `ScriptedMetadata` which would address the layering
violation.

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2023-03-06 13:14:15 -08:00
Dave Lee
8794712e88 [lldb] Add variable completion to dwim-print
Enable completion of variables for `dwim-print` command.

Differential Revision: https://reviews.llvm.org/D145124
2023-03-06 10:42:32 -08:00
Med Ismail Bennani
b9d4c94a60 [lldb/Plugins] Add Attach capabilities to ScriptedProcess
This patch adds process attach capabilities to the ScriptedProcess
plugin. This doesn't really expects a PID or process name, since the
process state is already script, however, this allows to create a
scripted process without requiring to have an executuble in the target.

In order to do so, this patch also turns the scripted process related
getters and setters from the `ProcessLaunchInfo` and
`ProcessAttachInfo` classes to a `ScriptedMetadata` instance and moves
it in the `ProcessInfo` class, so it can be accessed interchangeably.

This also adds the necessary SWIG wrappers to convert the internal
`Process{Attach,Launch}InfoSP` into a `SB{Attach,Launch}Info` to pass it
as argument the scripted process python implementation and convert it
back to the internal representation.

rdar://104577406

Differential Revision: https://reviews.llvm.org/D143104

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2023-03-03 19:33:02 -08:00
Med Ismail Bennani
3014a1c5a1 [lldb] Add scripted process launch/attach option to {,platform }process commands
This patch does several things:

First, it refactors the `CommandObject{,Platform}ProcessObject` command
option class into a separate `CommandOptionsProcessAttach` option group.

This will make sure both the `platform process attach` and `process attach`
command options will always stay in sync without having with duplicate
them each time. But more importantly, making this class an `OptionGroup`
allows us to combine with a `OptionGroupPythonClassWithDict` to add
support for the scripted process managing class name and user-provided
dictionary options.

This patch also improves feature parity between `ProcessLaunchInfo` and
`ProcessAttachInfo` with regard to ScriptedProcesses, by exposing the
various getters and setters necessary to use them through the SBAPI.

This is foundation work for adding support to "attach" to a process from
the scripted platform.

Differential Revision: https://reviews.llvm.org/D139945

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2023-03-03 19:33:02 -08:00
Med Ismail Bennani
9a9fce1fed [lldb] Fix {break,watch}point command function stopping behaviour
In order to run a {break,watch}point command, lldb can resolve to the
script interpreter to run an arbitrary piece of code or call into a
user-provided function. To do so, we will generate a wrapping function,
where we first copy lldb's internal dictionary keys into the
interpreter's global dictionary, copied inline the user code before
resetting the global dictionary to its previous state.

However, {break,watch}point commands can optionally return a value that
would tell lldb whether we should stop or not. This feature was
only implemented for breakpoint commands and since we inlined the user
code directly into the wrapping function, introducing an early return,
that caused lldb to let the interpreter global dictionary tinted with the
internal dictionary keys.

This patch fixes that issue while also adding the stopping behaviour to
watchpoint commands.

To do so, this patch refactors the {break,watch}point command creation
method, to let the lldb wrapper function generator know if the user code is
a function call or a arbitrary expression.

Then the wrapper generator, if the user input was a function call, the
wrapper function will call the user function and save the return value into
a variable. If the user input was an arbitrary expression, the wrapper  will
inline it into a nested function, call the nested function and save the
return value into the same variable. After resetting the interpreter global
dictionary to its previous state, the generated wrapper function will return
the varible containing the return value.

rdar://105461140

Differential Revision: https://reviews.llvm.org/D144688

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2023-02-28 11:39:58 -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
Dave Lee
920b46e108 [lldb] Add expression command options in dwim-print
Adopt `expression`'s options in `dwim-print`.

This is primarily added to support the `--language`/`-l` flag.

Differential Revision: https://reviews.llvm.org/D144114
2023-02-17 17:50:08 -08:00
Dave Lee
3328ee550c [lldb] Suppress persistent result when running po
Remove the persistent result variable after executing `po`.

Without this change, the following behavior happens:

```
(lldb) p thing
(NSObject *) $0 = 0x600000008000
(lldb) po thing
<NSObject: 0x600000008000>
(lldb) p thing
(NSObject *) $2 = 0x600000008000
(lldb) p $1
(NSObject *) $1 = 0x600000008000
```

Even though `po` hides the persistent result variable, it's still created - as $1 in
this example. It can be accessed even though its existence is not evident.

With this change, the persistent result is removed after the object description has
printed. Instead, this is the behavior:

```
(lldb) p thing
(NSObject *) $0 = 0x600000008000
(lldb) po thing
<NSObject: 0x600000008000>
(lldb) p thing
(NSObject *) $1 = 0x600000008000
```

The difference here is that the `po` doens't silently create a persistent result.

Differential Revision: https://reviews.llvm.org/D144044
2023-02-16 21:05:19 -08:00
Jim Ingham
9093f3c39b Report a useful error when someone passes an incorrect python class name. 2023-02-14 13:47:14 -08:00
Jason Molenda
eaeb8ddd4a [LLDB] add arch-specific watchpoint behavior defaults to lldb
lldb was originally designed to get the watchpoint exception behavior
from the gdb remote serial protocol stub -- exceptions are either
received before the instruction executes, or after the instruction
has executed.  This behavior was reported via two lldb extensions
to gdb RSP, so generic remote stubs like gdbserver or a JTAG stub,
would not tell lldb which behavior was correct, and it would default
to "exceptions are received after the instruction has executed".
Two architectures hard coded their correct "exceptions before
instruction" behavior, to work around this issue.

Most architectures have a fixed behavior of watchpoint exceptions,
and we can center that information in lldb.  We can allow a remote
stub to override the default behavior via our packet extensions
if it's needed on a specific target.

This patch also separates the fetching of the number of watchpoints
from whether exceptions are before/after the insn.  Currently if
lldb couldn't fetch the number of watchpoints (not really needed), it
also wouldn't get when exceptions are received, and watchpoint
handling would fail.  lldb doesn't actually use the number of
watchpoints for anything beyond printing it to the user.

Differential Revision: https://reviews.llvm.org/D143215
rdar://101426626
2023-02-14 11:35:39 -08:00