Commit Graph

707 Commits

Author SHA1 Message Date
Greg Clayton
c4fb7180cb [lldb][NFC] Make the target's SectionLoadList private. (#113278)
Lots of code around LLDB was directly accessing the target's section
load list. This NFC patch makes the section load list private so the
Target class can access it, but everyone else now uses accessor
functions. This allows us to control the resolving of addresses and will
allow for functionality in LLDB which can lazily resolve addresses in
JIT plug-ins with a future patch.
2025-01-14 20:12:46 -08:00
Adrian Prantl
87659a17d0 Reland: [lldb] Implement a formatter bytecode interpreter in C++
Compared to the python version, this also does type checking and error
handling, so it's slightly longer, however, it's still comfortably
under 500 lines.

Relanding with more explicit type conversions.
2024-12-10 16:37:53 -08:00
Sylvestre Ledru
a2fb70523a Revert "[lldb] Add cast to fix compile error on 32-bit platforms"
This reverts commit f6012a209d.

Revert "[lldb] Add cast to fix compile error on 32-but platforms"

This reverts commit d300337e93.

Revert "[lldb] Improve log message to include missing strings"

This reverts commit 0be3348485.

Revert "[lldb] Add comment"

This reverts commit e2bb47443d.

Revert "[lldb] Implement a formatter bytecode interpreter in C++"

This reverts commit 9a9c1d4a61.
2024-12-11 00:00:44 +01:00
Adrian Prantl
9a9c1d4a61 [lldb] Implement a formatter bytecode interpreter in C++
Compared to the python version, this also does type checking and error
handling, so it's slightly longer, however, it's still comfortably
under 500 lines.
2024-12-10 09:36:38 -08:00
Dave Lee
1a650fde4a [lldb] Load embedded type summary section (#7859) (#8040)
Add support for type summaries embedded into the binary.

These embedded summaries will typically be generated by Swift macros,
but can also be generated by any other means.

rdar://115184658
2024-12-10 09:36:38 -08:00
Adrian Prantl
6a8a4d51a4 [lldb] Refactor UserExpression::Evaluate to only have one error channel. (#117186)
Prior to this patch, the function returned an exit status, sometimes a
ValueObject with an error and a Status object. This patch removes the
Status object and ensures the error is consistently returned as the
error of the ValueObject.
2024-11-21 15:37:04 -08:00
jeffreytan81
24feaab838 Fix statistics dump to report per-target (#113723)
"statistics dump" currently report the statistics of all targets in
debugger instead of current target. This is wrong because there is a
"statistics dump --all-targets" option that supposed to include
everything.

This PR fixes the issue by only report statistics for current target
instead of all. It also includes the change to reset statistics debug
info/symbol table parsing/indexing time during debugger destroy. This is
required so that we report current statistics if we plan to reuse
lldb/lldb-dap across debug sessions

---------

Co-authored-by: jeffreytan81 <jeffreytan@fb.com>
2024-11-17 20:36:54 -08:00
cmtice
310351d94d [LLDB] Add framework for Data Inspection Language (DIL) work. (#115666)
Add the framework code for hooking up and calling the Data Inspection
Language (DIL) implementation, as an alternate implementation for the
'frame variable' command. For now, this is an opt-in option, via a
target setting 'target.experimental.use-DIL'. See
https://discourse.llvm.org/t/rfc-data-inspection-language/69893 for more
information about this project.

This PR does not actually call any of the DIL code; instead the piece
that will eventually call the DIL code
(StackFrame::DILEvaluateVariableExpression) calls back into the original
'frame variable' implementation.
2024-11-14 08:53:16 -08:00
Jonas Devlieghere
f109517d15 [lldb] Support overriding the disassembly CPU & features (#115382)
Add the ability to override the disassembly CPU and CPU features through
a target setting (`target.disassembly-cpu` and
`target.disassembly-features`) and a `disassemble` command option
(`--cpu` and `--features`).

This is especially relevant for architectures like RISC-V which relies
heavily on CPU extensions.

The majority of this patch is plumbing the options through. I recommend
looking at DisassemblerLLVMC and the test for the observable change in
behavior.
2024-11-11 16:27:15 -08:00
walter erquinigo
e952728f88 [LLDB] Retry Add a target.launch-working-dir setting
This retries the PR 113521 skipping a test in a remote environment.
2024-11-05 13:29:51 -05:00
Walter Erquinigo
5d39e0c7e1 Revert "[LLDB] Add a target.launch-working-dir setting" (#114973)
Reverts llvm/llvm-project#113521 due to build bot failures mentioned in
the original PR.
2024-11-05 07:12:20 -05:00
Walter Erquinigo
6620cd2523 [LLDB] Add a target.launch-working-dir setting (#113521)
Internally we use bazel in a way in which it can drop you in a LLDB
session with the target launched in a particular cwd, which is needed
for things to work. We've been making this automation work via `process
launch -w`. However, if later the user wants to restart the process with
`r`, then they end up using a different cwd for relaunching the process.
As a way to fix this, I'm adding a target-level setting that allows
configuring a default cwd used for launching the process without needing
the user to specify it manually.
2024-11-05 06:33:25 -05:00
Jonas Devlieghere
a57296ad41 [lldb] Create dependent modules in parallel (#114507)
Create dependent modules in parallel in Target::SetExecutableModule.
This change was inspired by #110646 which takes the same approach when
attaching. Jason suggested we could use the same approach when you
create a target in LLDB.

I used Slack for benchmarking, which loads 902 images.

```
Benchmark 1: ./bin/lldb /Applications/Slack.app/Contents/MacOS/Slack
  Time (mean ± σ):      1.225 s ±  0.003 s    [User: 3.977 s, System: 1.521 s]
  Range (min … max):    1.220 s …  1.229 s    10 runs

Benchmark 2: ./bin/lldb /Applications/Slack.app/Contents/MacOS/Slack
  Time (mean ± σ):      3.253 s ±  0.037 s    [User: 3.013 s, System: 0.248 s]
  Range (min … max):    3.211 s …  3.310 s    10 runs
```

We see about a 2x speedup, which matches what Jason saw for the attach
scenario. I also ran this under TSan to confirm this doesn't introduce
any races or deadlocks.
2024-11-04 13:32:22 -08:00
Jonas Devlieghere
4c8cc5a63b Revert "[lldb] Create dependent modules in parallel (#114507)"
This reverts commit b360dfd503.
2024-11-03 12:34:47 -08:00
Jonas Devlieghere
b360dfd503 [lldb] Create dependent modules in parallel (#114507)
Create dependent modules in parallel in Target::SetExecutableModule.
This change was inspired by #110646 which takes the same approach when
attaching. Jason suggested we could use the same approach when you
create a target in LLDB.

I used Slack for benchmarking, which loads 902 images.

```
Benchmark 1: ./bin/lldb /Applications/Slack.app/Contents/MacOS/Slack
  Time (mean ± σ):      1.225 s ±  0.003 s    [User: 3.977 s, System: 1.521 s]
  Range (min … max):    1.220 s …  1.229 s    10 runs

Benchmark 2: ./bin/lldb /Applications/Slack.app/Contents/MacOS/Slack
  Time (mean ± σ):      3.253 s ±  0.037 s    [User: 3.013 s, System: 0.248 s]
  Range (min … max):    3.211 s …  3.310 s    10 runs
```

We see about a 2x speedup, which matches what Jason saw for the attach
scenario. I also ran this under TSan to confirm this doesn't introduce
any races or deadlocks.
2024-11-02 09:38:10 -07:00
Jonas Devlieghere
b852fb1ec5 [lldb] Move ValueObject into its own library (NFC) (#113393)
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%" '{}' \;
```
2024-10-24 20:20:48 -07:00
Adrian Prantl
84fdfb9ca6 [lldb] Store expression evaluator diagnostics in an llvm::Error (NFC) (#106442)
…NFC]

This patch is the first patch in a series reworking of Pete Lawrence's
(@PortalPete) amazing proposal for better expression evaluator error
messages (https://github.com/llvm/llvm-project/pull/80938)

This patch is preparatory patch for improving the rendering of
expression evaluator diagnostics. Currently diagnostics are rendered
into a string and the command interpreter layer then textually parses
words like "error:" to (sometimes) color the output accordingly. In
order to enable user interfaces to do better with diagnostics, we need
to store them in a machine-readable fromat. This patch does this by
adding a new llvm::Error kind wrapping a DiagnosticDetail struct that
is used when the error type is eErrorTypeExpression. Multiple
diagnostics are modeled using llvm::ErrorList.

Right now the extra information is not used by the CommandInterpreter,
this will be added in a follow-up patch!
2024-09-27 16:09:52 -07:00
Jonas Devlieghere
b3b6141ba1 [lldb] Fix two formatv issues in LDB_LOG (NFC) 2024-09-25 10:17:09 -07:00
dlav-sc
6ad268e391 [lldb] refactor Target::Install function (#108996)
refactor Target::Install function
2024-09-23 08:54:16 +01:00
Med Ismail Bennani
f732157a9d [lldb/Interpreter] Introduce ScriptedStopHook{,Python}Interface & make use of it (#109498)
This patch re-lands #105449 and fixes the various test failures.

---------

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2024-09-20 16:55:47 -07:00
David Spickett
801046e330 Revert "[lldb] Fix SWIG wrapper compilation error"
...and "[lldb/Interpreter] Introduce `ScriptedStopHook{,Python}Interface` & make use of it (#105449)"

This reverts commit 76b827bb4d, and commit 1e131ddfa8
because the first commit caused the test command-stop-hook-output.test to fail.
2024-09-20 09:57:07 +00:00
Med Ismail Bennani
1e131ddfa8 [lldb/Interpreter] Introduce ScriptedStopHook{,Python}Interface & make use of it (#105449)
This patch introduces new `ScriptedStopHook{,Python}Interface` classes
that make use of the Scripted Interface infrastructure and makes use of
it in `StopHookScripted`.

It also relax the requirement on the number of argument for initializing
scripting extension if the size of the interface parameter pack contains
1 less element than the extension maximum number of positional arguments
for this initializer.
This addresses the cases where the embedded interpreter session
dictionary is passed to the extension initializer which is not used most
of the time.

---------

Signed-off-by: Med Ismail Bennani <ismail@bennani.ma>
2024-09-19 23:35:34 -07:00
Youngsuk Kim
d7796855b8 [lldb] Nits on uses of llvm::raw_string_ostream (NFC) (#108745)
As specified in the docs,
1) raw_string_ostream is always unbuffered and
2) the underlying buffer may be used directly

( 65b13610a5 for further reference )

* Don't call raw_string_ostream::flush(), which is essentially a no-op.
* Avoid unneeded calls to raw_string_ostream::str(), to avoid excess
indirection.
2024-09-16 00:26:51 -04:00
Jacob Lalonde
22144e20cb [LLDB][Data Formatters] Calculate average and total time for summary providers within lldb (#102708)
This PR adds a statistics provider cache, which allows an individual
target to keep a rolling tally of it's total time and number of
invocations for a given summary provider. This information is then
available in statistics dump to help slow summary providers, and gleam
more into insight into LLDB's time use.
2024-09-10 09:58:43 -07:00
Adrian Prantl
b798f4bd50 [lldb] Make deep copies of Status explicit (NFC) (#107170) 2024-09-05 12:44:13 -07:00
Lang Hames
e6cbea1157 Revert "[lldb] unique_ptr-ify some GetUserExpression APIs. (#106034)"
This reverts commit 3c5ab5a75a while I investigate
bot failures (e.g. https://lab.llvm.org/buildbot/#/builders/163/builds/4286).
2024-08-28 15:49:40 +10:00
Lang Hames
3c5ab5a75a [lldb] unique_ptr-ify some GetUserExpression APIs. (#106034)
These methods already returned a uniquely owned object, this just makes
them self-documenting.
2024-08-28 15:36:57 +10:00
Adrian Prantl
0642cd768b [lldb] Turn lldb_private::Status into a value type. (#106163)
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.
2024-08-27 10:59:31 -07:00
Jason Molenda
c1e401f362 [lldb] Change the two remaining SInt64 settings in Target to uint (#105460)
TargetProperties.td had a few settings listed as signed integral values,
but the Target.cpp methods reading those values were reading them as
unsigned. e.g. target.max-memory-read-size, some accesses of
target.max-children-count, still today, previously
target.max-string-summary-length.

After Jonas' change to use templates to read these values in
https://reviews.llvm.org/D149774, when the code tried to fetch these
values, we'd eventually end up calling OptionValue::GetAsUInt64 which
checks that the value is actually a UInt64 before returning it; finding
that it was an SInt64, it would drop the user setting and return the
default value. This manifested as a bug that target.max-memory-read-size
is never used for memory read.

target.max-children-count is less straightforward, where one read of
that setting was fetching it as an int64_t, the other as a uint64_t.

I suspect all of these settings were originally marked as SInt64 so a
user could do -1 for "infinite", getting it static_cast to a UINT64_MAX
value along the way. I can't find any documentation for this behavior,
but it seems like something Greg would have done. We've partially lost
that behavior already via
https://github.com/llvm/llvm-project/pull/72233 for
target.max-string-summary-length, and this further removes it.

We're still fetching UInt64's and returning them as uint32_t's but I'm
not overly pressed about someone setting a count/size limit over 4GB.

I added a simple API test for the memory read setting limit.
2024-08-22 10:10:15 -07:00
royitaqi
47721d4618 [lldb] Realpath symlinks for breakpoints (#102223)
Improve the chance of resolving file/line breakpoints by realpath'ing the support files before doing a second match attempt, with some conditions applied.

A working [hello-world example](https://github.com/royitaqi/lldb_demos/blob/main/realpath/README.md).

See [patch](https://github.com/llvm/llvm-project/pull/102223) for more info about problem/motivation, details of the feature, new settings, telemetries and tests.
2024-08-15 11:26:24 -07:00
Alexandre Perez
0a01e8ff53 [lldb] Allow mapping object file paths (#101361)
This introduces a `target.object-map` which allows us to remap module
locations, much in the same way as source mapping works today. This is
useful, for instance, when debugging coredumps, so we can replace some
of the locations where LLDB attempts to load shared libraries and
executables from, without having to setup an entire sysroot.
2024-07-31 10:57:40 -07:00
Adrian Prantl
af31883341 Add a createError variant without error code (NFC) (#93209)
For the significant amount of call sites that want to create an
incontrovertible error, such a wrapper function creates a significant
readability improvement and lowers the cost of entry to add error
handling in more places.
2024-05-23 14:22:07 -07:00
aabhinavg
c285297889 [lldb] Fix redundant condition in Target.cpp (#91882)
This commit addresses issue #87244, where a redundant condition was
found in the Target.cpp file. Static analyzer cppcheck flagged the issue
in the Target.cpp file

fix #87244
2024-05-14 09:14:17 +01:00
Adrian Prantl
975eca0e6a Add a new SBExpressionOptions::SetLanguage() API (NFCI) (#89981)
that separates out language and version. To avoid reinventing the wheel
and introducing subtle incompatibilities, this API uses the table of
languages and versiond defined by the upcoming DWARF 6 standard
(https://dwarfstd.org/languages-v6.html). While the DWARF 6 spec is not
finialized, the list of languages is broadly considered stable.

The primary motivation for this is to allow the Swift language plugin to
switch between language dialects between, e.g., Swift 5.9 and 6.0 with
out introducing a ton of new language codes. On the main branch this
change is considered NFC.

Depends on https://github.com/llvm/llvm-project/pull/89980
2024-04-29 13:26:24 -07:00
Alex Langford
5779483527 [lldb][nfc] Move broadcaster class strings away from ConstString (#89690)
These are hardcoded strings that are already present in the data section
of the binary, no need to immediately place them in the ConstString
StringPools. Lots of code still calls `GetBroadcasterClass` and places
the return value into a ConstString. Changing that would be a good
follow-up.

Additionally, calls to these functions are still wrapped in ConstStrings
at the SBAPI layer. This is because we must guarantee the lifetime of
all strings handed out publicly.
2024-04-24 12:13:18 -07:00
Dave Lee
ca7492fae4 [lldb] Extract getter function for experimental target properties (NFC) (#83504)
In Swift's downstream lldb, there are a number of experimental properties. This change 
extracts a getter function containing the common logic for getting a boolean valued 
experimental property.

This also deletes `SetInjectLocalVariables` which isn't used anywhere.
2024-03-06 20:41:46 -08:00
Adrian Prantl
8a87f763a6 Aim debugserver workaround more precisely. (#83099) 2024-02-27 08:14:46 -08:00
Adrian Prantl
01450dd1c6 Change debugserver to report the cpu(sub)type of process, not the host.
This way debugserver can correctly report qProcessInfo for arm64
processes on arm64e-capable hosts.

Patch implemented with help from Jason Molenda!
2024-02-26 09:57:07 -08:00
Adrian Prantl
f9f331652d Replace ArchSpec::PiecewiseCompare() with Triple::operator==()
Looking ast the definition of both functions this is *almost* an NFC
change, except that Triple also looks at the SubArch (important) and
ObjectFormat (less so).

This fixes a bug that only manifests with how Xcode uses the SBAPI to
attach to a process by name: it guesses the architecture based on the
system. If the system is arm64 and the Process is arm64e Target fails
to update the triple because it deemed the two to be equivalent.

rdar://123338218
2024-02-26 09:57:07 -08:00
Adrian Prantl
3f91bdfdd5 Revert "Replace ArchSpec::PiecewiseCompare() with Triple::operator==()"
This reverts commit 5e6bed8c0ea2f7fe380127763c8f753adae0fc1b while investigating the bots.
2024-02-23 15:26:14 -08:00
Adrian Prantl
25940956e6 Replace ArchSpec::PiecewiseCompare() with Triple::operator==() (#82804)
Looking ast the definition of both functions this is *almost* an NFC
change, except that Triple also looks at the SubArch (important) and
ObjectFormat (less so).

This fixes a bug that only manifests with how Xcode uses the SBAPI to
attach to a process by name: it guesses the architecture based on the
system. If the system is arm64 and the Process is arm64e Target fails to
update the triple because it deemed the two to be equivalent.

rdar://123338218
2024-02-23 14:00:15 -08:00
Wanyi
2217837c33 Support statistics dump summary only mode (#80745)
Add a new --summary option to statistics dump command so that it is
much more light weight than the full version.
Introduce a new SBStatisticsOptions API setting the verbosity of statistics dump. 
[PR
#80218](https://github.com/llvm/llvm-project/pull/80218#discussion_r1473639878)
2024-02-06 19:47:34 -05:00
Alex Langford
0cea54a382 [lldb][NFCI] Remove EventData* param from BroadcastEvent (#78773)
BroadcastEvent currently takes its EventData* param and shoves it into
an Event object, which takes ownership of the pointer and places it into
a shared_ptr to manage the lifetime.

Instead of relying on `new` and passing raw pointers around, I think it
would make more sense to create the shared_ptr up front.
2024-01-22 10:46:20 -08:00
jimingham
9d3aec5535 Fix a stall in running quit while a live process is running (#74687)
We need to generate events when finalizing, or we won't know that we
succeeded in stopping the process to detach/kill. Instead, we stall and
then after our 20 interrupt timeout, we kill the process (even if we
were supposed to detach) and exit.

OTOH, we have to not generate events when the Process is being
destructed because shared_from_this has already been torn down, and
using it will cause crashes.
2023-12-07 14:36:27 -08:00
Jason Molenda
c73a3f16f8 [lldb] [mostly NFC] Large WP foundation: WatchpointResources (#68845)
This patch is rearranging code a bit to add WatchpointResources to
Process. A WatchpointResource is meant to represent a hardware
watchpoint register in the inferior process. It has an address, a size,
a type, and a list of Watchpoints that are using this
WatchpointResource.

This current patch doesn't add any of the features of
WatchpointResources that make them interesting -- a user asking to watch
a 24 byte object could watch this with three 8 byte WatchpointResources.
Or a Watchpoint on 1 byte at 0x1002 and a second watchpoint on 1 byte at
0x1003, these must both be served by a single WatchpointResource on that
doubleword at 0x1000 on a 64-bit target, if two hardware watchpoint
registers were used to track these separately, one of them may not be
hit. Or if you have one Watchpoint on a variable with a condition set,
and another Watchpoint on that same variable with a command defined or
different condition, or ignorecount, both of those Watchpoints need to
evaluate their criteria/commands when their WatchpointResource has been
hit.

There's a bit of code movement to rearrange things in the direction I'll
need for implementing this feature, so I want to start with reviewing &
landing this mostly NFC patch and we can focus on the algorithmic
choices about how WatchpointResources are shared and handled as they're
triggeed, separately.

This patch also stops printing "Watchpoint <n> hit: old value: <x>, new
vlaue: <y>" for Read watchpoints. I could make an argument for print
"Watchpoint <n> hit: current value <x>" but the current output doesn't
make any sense, and the user can print the value if they are
particularly interested. Read watchpoints are used primarily to
understand what code is reading a variable.

This patch adds more fallbacks for how to print the objects being
watched if we have types, instead of assuming they are all integral
values, so a struct will print its elements. As large watchpoints are
added, we'll be doing a lot more of those.

To track the WatchpointSP in the WatchpointResources, I changed the
internal API which took a WatchpointSP and devolved it to a Watchpoint*,
which meant touching several different Process files. I removed the
watchpoint code in ProcessKDP which only reported that watchpoints
aren't supported, the base class does that already.

I haven't yet changed how we receive a watchpoint to identify the
WatchpointResource responsible for the trigger, and identify all
Watchpoints that are using this Resource to evaluate their conditions
etc. This is the same work that a BreakpointSite needs to do when it has
been tiggered, where multiple Breakpoints may be at the same address.

There is not yet any printing of the Resources that a Watchpoint is
implemented in terms of ("watchpoint list", or
SBWatchpoint::GetDescription).

"watchpoint set var" and "watchpoint set expression" take a size
argument which was previously 1, 2, 4, or 8 (an enum). I've changed this
to an unsigned int. Most hardware implementations can only watch 1, 2,
4, 8 byte ranges, but with Resources we'll allow a user to ask for
different sized watchpoints and set them in hardware-expressble terms
soon.

I've annotated areas where I know there is work still needed with
LWP_TODO that I'll be working on once this is landed.

I've tested this on aarch64 macOS, aarch64 Linux, and Intel macOS.

https://discourse.llvm.org/t/rfc-large-watchpoint-support-in-lldb/72116
(cherry picked from commit fc6b72523f)
2023-11-30 14:59:10 -08:00
David Spickett
b0af8a1ede Revert "[lldb] [mostly NFC] Large WP foundation: WatchpointResources (#68845)"
...and follow ups.

As it has caused test failures on Linux Arm and AArch64:
https://lab.llvm.org/buildbot/#/builders/96/builds/49126
https://lab.llvm.org/buildbot/#/builders/17/builds/45824

```
  lldb-shell :: Subprocess/clone-follow-child-wp.test
  lldb-shell :: Subprocess/fork-follow-child-wp.test
  lldb-shell :: Subprocess/vfork-follow-child-wp.test
```

This reverts commit a6c62bf1a4,
commit a0a1ff3ab4 and commit
fc6b72523f.
2023-11-28 09:39:37 +00:00
Jason Molenda
fc6b72523f [lldb] [mostly NFC] Large WP foundation: WatchpointResources (#68845)
This patch is rearranging code a bit to add WatchpointResources to
Process. A WatchpointResource is meant to represent a hardware
watchpoint register in the inferior process. It has an address, a size,
a type, and a list of Watchpoints that are using this
WatchpointResource.

This current patch doesn't add any of the features of
WatchpointResources that make them interesting -- a user asking to watch
a 24 byte object could watch this with three 8 byte WatchpointResources.
Or a Watchpoint on 1 byte at 0x1002 and a second watchpoint on 1 byte at
0x1003, these must both be served by a single WatchpointResource on that
doubleword at 0x1000 on a 64-bit target, if two hardware watchpoint
registers were used to track these separately, one of them may not be
hit. Or if you have one Watchpoint on a variable with a condition set,
and another Watchpoint on that same variable with a command defined or
different condition, or ignorecount, both of those Watchpoints need to
evaluate their criteria/commands when their WatchpointResource has been
hit.

There's a bit of code movement to rearrange things in the direction I'll
need for implementing this feature, so I want to start with reviewing &
landing this mostly NFC patch and we can focus on the algorithmic
choices about how WatchpointResources are shared and handled as they're
triggeed, separately.

This patch also stops printing "Watchpoint <n> hit: old value: <x>, new
vlaue: <y>" for Read watchpoints. I could make an argument for print
"Watchpoint <n> hit: current value <x>" but the current output doesn't
make any sense, and the user can print the value if they are
particularly interested. Read watchpoints are used primarily to
understand what code is reading a variable.

This patch adds more fallbacks for how to print the objects being
watched if we have types, instead of assuming they are all integral
values, so a struct will print its elements. As large watchpoints are
added, we'll be doing a lot more of those.

To track the WatchpointSP in the WatchpointResources, I changed the
internal API which took a WatchpointSP and devolved it to a Watchpoint*,
which meant touching several different Process files. I removed the
watchpoint code in ProcessKDP which only reported that watchpoints
aren't supported, the base class does that already.

I haven't yet changed how we receive a watchpoint to identify the
WatchpointResource responsible for the trigger, and identify all
Watchpoints that are using this Resource to evaluate their conditions
etc. This is the same work that a BreakpointSite needs to do when it has
been tiggered, where multiple Breakpoints may be at the same address.

There is not yet any printing of the Resources that a Watchpoint is
implemented in terms of ("watchpoint list", or
SBWatchpoint::GetDescription).

"watchpoint set var" and "watchpoint set expression" take a size
argument which was previously 1, 2, 4, or 8 (an enum). I've changed this
to an unsigned int. Most hardware implementations can only watch 1, 2,
4, 8 byte ranges, but with Resources we'll allow a user to ask for
different sized watchpoints and set them in hardware-expressble terms
soon.

I've annotated areas where I know there is work still needed with
LWP_TODO that I'll be working on once this is landed.

I've tested this on aarch64 macOS, aarch64 Linux, and Intel macOS.

https://discourse.llvm.org/t/rfc-large-watchpoint-support-in-lldb/72116
2023-11-27 13:28:59 -08:00
Alex Langford
f4df0c48e9 [lldb][NFCI] Change parameter type in Target::AddNameToBreakpoint (#71241)
By itself this change does very little, but I plan on refactoring
something from StructuredData and it gets much easier with this change.
2023-11-06 12:45:02 -08:00
Jonas Devlieghere
f9632cee30 [lldb] Remove FileSpecList::GetFileSpecPointerAtIndex (NFC)
There's only one use and it eventually converts the pointer into a
reference. Simplify things and always use references.
2023-10-19 13:13:31 -07:00
José Lira Junior
ac0dda8942 [lldb] add stop-at-user-entry option to process launch (#67019)
## Description
This pull request adds a new `stop-at-user-entry` option to LLDB
`process launch` command, allowing users to launch a process and pause
execution at the entry point of the program (for C-based languages,
`main` function).

## Motivation
This option provides a convenient way to begin debugging a program by
launching it and breaking at the desired entry point.

## Changes Made
- Added `stop-at-user-entry` option to `Options.td` and the
corresponding case in `CommandOptionsProcessLaunch.cpp` (short option is
'm')
- Implemented `GetUserEntryPointName` method in the Language plugins
available at the moment.
- Declared the `CreateBreakpointAtUserEntry` method in the Target API.
- Create Shell test for the command
`command-process-launch-user-entry.test`.

## Usage
`process launch --stop-at-user-entry` or `process launch -m` launches
the process and pauses execution at the entry point of the program.
2023-10-09 16:43:59 -07:00