[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 hardwar

[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 fc6b72523f3d73b921690a713e97a433c96066c6)

show more ...

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/9

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 a6c62bf1a4717accc852463b664cd1012237d334,
commit a0a1ff3ab40e347589b4e27d8fd350c600526735 and commit
fc6b72523f3d73b921690a713e97a433c96066c6.

show more ...

[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 hardwa

[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

show more ...

[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

[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2

Improve LLDB reliability by fixing the following "uninitialized variables" static code inspection warnings from
scan.c

[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2

Improve LLDB reliability by fixing the following "uninitialized variables" static code inspection warnings from
scan.coverity.com:

1476275, 1274012, 1455035, 1364789, 1454282
1467483, 1406152, 1406255, 1454837, 1454416
1467446, 1462022, 1461909, 1420566, 1327228
1367767, 1431254, 1467299, 1312678, 1431780
1454731, 1490403

Differential Revision: https://reviews.llvm.org/D130528

show more ...

Revert "[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2"

This reverts commit b9aedd94e6796e4b4866ab4c091b736b3db58cb7.

[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2

Improve LLDB reliability by fixing the following "uninitialized variables" static code inspection warnings from
scan.c

[LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan. Part 2

Improve LLDB reliability by fixing the following "uninitialized variables" static code inspection warnings from
scan.coverity.com:

1476275, 1274012, 1455035, 1364789, 1454282
1467483, 1406152, 1406255, 1454837, 1454416
1467446, 1462022, 1461909, 1420566, 1327228
1367767, 1431254, 1467299, 1312678, 1431780
1454731, 1490403

Differential Revision: https://reviews.llvm.org/D130528

show more ...

[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
inf

[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.

show more ...

[lldb] Convert "LLDB" log channel to the new API

[lldb][NFC] Inclusive Language: rename master plan to controlling plan

[NFC] As part of using inclusive language within the llvm project, this patch
renames master plan to controlling plan in lldb.

[lldb][NFC] Inclusive Language: rename master plan to controlling plan

[NFC] As part of using inclusive language within the llvm project, this patch
renames master plan to controlling plan in lldb.

Reviewed By: jingham

Differential Revision: https://reviews.llvm.org/D113019

show more ...

[lldb] Avoid moving ThreadPlanSP from plans vector

Change `ThreadPlanStack::PopPlan` and `::DiscardPlan` to not do the following:

1. Move the last plan, leaving a moved `ThreadPlanSP` in the plans

[lldb] Avoid moving ThreadPlanSP from plans vector

Change `ThreadPlanStack::PopPlan` and `::DiscardPlan` to not do the following:

1. Move the last plan, leaving a moved `ThreadPlanSP` in the plans vector
2. Operate on the last plan
3. Pop the last plan off the plans vector

This leaves a period of time where the last element in the plans vector has been moved. I am not sure what, if any, guarantees there are when doing this, but it seems like it would/could leave a null `ThreadPlanSP` in the container. There are asserts in place to prevent empty/null `ThreadPlanSP` instances from being pushed on to the stack, and so this could break that invariant during multithreaded access to the thread plan stack.

An open question is whether this use of `std::move` was the result of a measure performance problem.

Differential Revision: https://reviews.llvm.org/D106171

show more ...

[lldb] Minor refinements to ThreadPlan::RestoreThreadState (NFC)

Correct `RestoreThreadState` to a `void` return type. Also, update the signature of its
callee, `Thread::RestoreThreadStateFromCheckp

[lldb] Minor refinements to ThreadPlan::RestoreThreadState (NFC)

Correct `RestoreThreadState` to a `void` return type. Also, update the signature of its
callee, `Thread::RestoreThreadStateFromCheckpoint`, by updating it to a `void` return
type, and making it non-`virtual`.

Differential Revision: https://reviews.llvm.org/D96688

show more ...

[lldb] Don't use static locals for return value storage in some *AsCString functions

Let's just return a std::string to make this safe. formatv seemed overkill for formatting
the return values as th

[lldb] Don't use static locals for return value storage in some *AsCString functions

Let's just return a std::string to make this safe. formatv seemed overkill for formatting
the return values as they all just append an integer value to a constant string.

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D84505

show more ...

Make ThreadPlans use TID and Process, rather than Thread *.

Differential Revision: https://reviews.llvm.org/D75711

[lldb][NFC] Fix all formatting errors in .cpp file headers

Summary:
A *.cpp file header in LLDB (and in LLDB) should like this:
```
//===-- TestUtilities.cpp ----------------------------------------

[lldb][NFC] Fix all formatting errors in .cpp file headers

Summary:
A *.cpp file header in LLDB (and in LLDB) should like this:
```
//===-- TestUtilities.cpp -------------------------------------------------===//
```
However in LLDB most of our source files have arbitrary changes to this format and
these changes are spreading through LLDB as folks usually just use the existing
source files as templates for their new files (most notably the unnecessary
editor language indicator `-*- C++ -*-` is spreading and in every review
someone is pointing out that this is wrong, resulting in people pointing out that this
is done in the same way in other files).

This patch removes most of these inconsistencies including the editor language indicators,
all the different missing/additional '-' characters, files that center the file name, missing
trailing `===//` (mostly caused by clang-format breaking the line).

Reviewers: aprantl, espindola, jfb, shafik, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: dexonsmith, wuzish, emaste, sdardis, nemanjai, kbarton, MaskRay, atanasyan, arphaman, jfb, abidh, jsji, JDevlieghere, usaxena95, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D73258

show more ...

[Logging] Replace Log::Printf with LLDB_LOG macro (NFC)

This patch replaces explicit calls to log::Printf with the new LLDB_LOGF
macro. The macro is similar to LLDB_LOG but supports printf-style for

[Logging] Replace Log::Printf with LLDB_LOG macro (NFC)

This patch replaces explicit calls to log::Printf with the new LLDB_LOGF
macro. The macro is similar to LLDB_LOG but supports printf-style format
strings, instead of formatv-style format strings.

So instead of writing:

if (log)
log->Printf("%s\n", str);

You'd write:

LLDB_LOG(log, "%s\n", str);

This change was done mechanically with the command below. I replaced the
spurious if-checks with vim, since I know how to do multi-line
replacements with it.

find . -type f -name '*.cpp' -exec \
sed -i '' -E 's/log->Printf\(/LLDB_LOGF\(log, /g' "{}" +

Differential revision: https://reviews.llvm.org/D65128

llvm-svn: 366936

show more ...

[Target] Return an llvm::Expected from GetEntryPointAddress (NFC)

Instead of taking a status and potentially returning an invalid address,
return an expected which is guaranteed to contain a valid

[Target] Return an llvm::Expected from GetEntryPointAddress (NFC)

Instead of taking a status and potentially returning an invalid address,
return an expected which is guaranteed to contain a valid address.

llvm-svn: 366521

show more ...

Fall back to dyld's _dyld_start when no LC_MAIN / main() func can be found

The new DriverKit user-land kernel drivers in macOS 10.15 / Catalina
do not have a main() function or an LC_MAIN load comm

Fall back to dyld's _dyld_start when no LC_MAIN / main() func can be found

The new DriverKit user-land kernel drivers in macOS 10.15 / Catalina
do not have a main() function or an LC_MAIN load command. lldb uses
the address of main() as the return address for inferior function
calls; it puts a breakpoint on main, runs the inferior function call,
and when the main() breakpoint is hit, lldb knows unambiguously that
the inferior function call ran to completion - no other function calls
main.

This change hoists the logic for finding the "entry address" from
ThreadPlanCallFunction to Target. It changes the logic to first
try to get the entry address from the main executable module,
but if that module does not have one, it will iterate through all
modules looking for an entry address.

The patch also adds code to ObjectFileMachO to use dyld's
_dyld_start function as an entry address.

<rdar://problem/52343958>

Differential Revision: https://reviews.llvm.org/D64897

llvm-svn: 366493

show more ...

[NFC] Remove ASCII lines from comments

A lot of comments in LLDB are surrounded by an ASCII line to delimit the
begging and end of the comment.

Its use is not really consistent across the code base

[NFC] Remove ASCII lines from comments

A lot of comments in LLDB are surrounded by an ASCII line to delimit the
begging and end of the comment.

Its use is not really consistent across the code base, sometimes the
lines are longer, sometimes they are shorter and sometimes they are
omitted. Furthermore, it looks kind of weird with the 80 column limit,
where the comment actually extends past the line, but not by much.
Furthermore, when /// is used for Doxygen comments, it looks
particularly odd. And when // is used, it incorrectly gives the
impression that it's actually a Doxygen comment.

I assume these lines were added to improve distinguishing between
comments and code. However, given that todays editors and IDEs do a
great job at highlighting comments, I think it's worth to drop this for
the sake of consistency. The alternative is fixing all the
inconsistencies, which would create a lot more churn.

Differential revision: https://reviews.llvm.org/D60508

llvm-svn: 358135

show more ...

Use std::make_shared in LLDB (NFC)

Unlike std::make_unique, which is only available since C++14,
std::make_shared is available since C++11. Not only is std::make_shared
a lot more readable compared

Use std::make_shared in LLDB (NFC)

Unlike std::make_unique, which is only available since C++14,
std::make_shared is available since C++11. Not only is std::make_shared
a lot more readable compared to ::reset(new), it also performs a single
heap allocation for the object and control block.

Differential revision: https://reviews.llvm.org/D57990

llvm-svn: 353764

show more ...

Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the ne

Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636

show more ...

Remove header grouping comments.

This patch removes the comments grouping header includes. They were
added after running IWYU over the LLDB codebase. However they add little
value, are often outdate

Remove header grouping comments.

This patch removes the comments grouping header includes. They were
added after running IWYU over the LLDB codebase. However they add little
value, are often outdates and burdensome to maintain.

llvm-svn: 346626

show more ...

Move dumping code out of RegisterValue class

Summary:
The dump function was the only part of this class which depended on
high-level functionality. This was due to the DumpDataExtractor
function, wh

Move dumping code out of RegisterValue class

Summary:
The dump function was the only part of this class which depended on
high-level functionality. This was due to the DumpDataExtractor
function, which uses info from a running target to control dump format
(although, RegisterValue doesn't really use the high-level part of
DumpDataExtractor).

This patch follows the same approach done for the DataExtractor class,
and extracts the dumping code into a separate function/file. This file
can stay in the higher level code, while the RegisterValue class and
anything that does not depend in dumping can stay go to lower layers.

The XCode project will need to be updated after this patch.

Reviewers: zturner, jingham, clayborg

Subscribers: lldb-commits, mgorny

Differential Revision: https://reviews.llvm.org/D48351

llvm-svn: 337832

show more ...

Reflow paragraphs in comments.

This is intended as a clean up after the big clang-format commit
(r280751), which unfortunately resulted in many of the comment
paragraphs in LLDB being very hard to r

Reflow paragraphs in comments.

This is intended as a clean up after the big clang-format commit
(r280751), which unfortunately resulted in many of the comment
paragraphs in LLDB being very hard to read.

FYI, the script I used was:

import textwrap
import commands
import os
import sys
import re
tmp = "%s.tmp"%sys.argv[1]
out = open(tmp, "w+")
with open(sys.argv[1], "r") as f:
header = ""
text = ""
comment = re.compile(r'^( *//) ([^ ].*)$')
special = re.compile(r'^((([A-Z]+[: ])|([0-9]+ )).*)|(.*;)$')
for line in f:
match = comment.match(line)
if match and not special.match(match.group(2)):
# skip intentionally short comments.
if not text and len(match.group(2)) < 40:
out.write(line)
continue

if text:
text += " " + match.group(2)
else:
header = match.group(1)
text = match.group(2)

continue

if text:
filled = textwrap.wrap(text, width=(78-len(header)),
break_long_words=False)
for l in filled:
out.write(header+" "+l+'\n')
text = ""

out.write(line)

os.rename(tmp, sys.argv[1])

Differential Revision: https://reviews.llvm.org/D46144

llvm-svn: 331197

show more ...

Rename Error -> Status.

This renames the LLDB error class to Status, as discussed
on the lldb-dev mailing list.

A change of this magnitude cannot easily be done without
find and replace, but that h

Rename Error -> Status.

This renames the LLDB error class to Status, as discussed
on the lldb-dev mailing list.

A change of this magnitude cannot easily be done without
find and replace, but that has potential to catch unwanted
occurrences of common strings such as "Error". Every effort
was made to find all the obvious things such as the word "Error"
appearing in a string, etc, but it's possible there are still
some lingering occurences left around. Hopefully nothing too
serious.

llvm-svn: 302872

show more ...