259 Commits

Author SHA1 Message Date
Adrian Prantl
f01f80ce6c
[lldb] Extend frame recognizers to hide frames from backtraces (#104523)
Compilers and language runtimes often use helper functions that are
fundamentally uninteresting when debugging anything but the
compiler/runtime itself. This patch introduces a user-extensible
mechanism that allows for these frames to be hidden from backtraces and
automatically skipped over when navigating the stack with `up` and
`down`.

This does not affect the numbering of frames, so `f <N>` will still
provide access to the hidden frames. The `bt` output will also print a
hint that frames have been hidden.

My primary motivation for this feature is to hide thunks in the Swift
programming language, but I'm including an example recognizer for
`std::function::operator()` that I wished for myself many times while
debugging LLDB.

rdar://126629381


Example output. (Yes, my proof-of-concept recognizer could hide even
more frames if we had a method that returned the function name without
the return type or I used something that isn't based off regex, but it's
really only meant as an example).

before:
```
(lldb) thread backtrace --filtered=false
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
  * frame #0: 0x0000000100001f04 a.out`foo(x=1, y=1) at main.cpp:4:10
    frame #1: 0x0000000100003a00 a.out`decltype(std::declval<int (*&)(int, int)>()(std::declval<int>(), std::declval<int>())) std::__1::__invoke[abi:se200000]<int (*&)(int, int), int, int>(__f=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:149:25
    frame #2: 0x000000010000399c a.out`int std::__1::__invoke_void_return_wrapper<int, false>::__call[abi:se200000]<int (*&)(int, int), int, int>(__args=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:216:12
    frame #3: 0x0000000100003968 a.out`std::__1::__function::__alloc_func<int (*)(int, int), std::__1::allocator<int (*)(int, int)>, int (int, int)>::operator()[abi:se200000](this=0x000000016fdff280, __arg=0x000000016fdff224, __arg=0x000000016fdff220) at function.h:171:12
    frame #4: 0x00000001000026bc a.out`std::__1::__function::__func<int (*)(int, int), std::__1::allocator<int (*)(int, int)>, int (int, int)>::operator()(this=0x000000016fdff278, __arg=0x000000016fdff224, __arg=0x000000016fdff220) at function.h:313:10
    frame #5: 0x0000000100003c38 a.out`std::__1::__function::__value_func<int (int, int)>::operator()[abi:se200000](this=0x000000016fdff278, __args=0x000000016fdff224, __args=0x000000016fdff220) const at function.h:430:12
    frame #6: 0x0000000100002038 a.out`std::__1::function<int (int, int)>::operator()(this= Function = foo(int, int) , __arg=1, __arg=1) const at function.h:989:10
    frame #7: 0x0000000100001f64 a.out`main(argc=1, argv=0x000000016fdff4f8) at main.cpp:9:10
    frame #8: 0x0000000183cdf154 dyld`start + 2476
(lldb) 
```

after

```
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
  * frame #0: 0x0000000100001f04 a.out`foo(x=1, y=1) at main.cpp:4:10
    frame #1: 0x0000000100003a00 a.out`decltype(std::declval<int (*&)(int, int)>()(std::declval<int>(), std::declval<int>())) std::__1::__invoke[abi:se200000]<int (*&)(int, int), int, int>(__f=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:149:25
    frame #2: 0x000000010000399c a.out`int std::__1::__invoke_void_return_wrapper<int, false>::__call[abi:se200000]<int (*&)(int, int), int, int>(__args=0x000000016fdff280, __args=0x000000016fdff224, __args=0x000000016fdff220) at invoke.h:216:12
    frame #6: 0x0000000100002038 a.out`std::__1::function<int (int, int)>::operator()(this= Function = foo(int, int) , __arg=1, __arg=1) const at function.h:989:10
    frame #7: 0x0000000100001f64 a.out`main(argc=1, argv=0x000000016fdff4f8) at main.cpp:9:10
    frame #8: 0x0000000183cdf154 dyld`start + 2476
Note: Some frames were hidden by frame recognizers
```
2024-08-20 16:01:22 -07:00
Adrian Prantl
d1bc75c0bc Convert ValueObject::Dump() to return llvm::Error() (NFCish)
This change by itself has no measurable effect on the LLDB
testsuite. I'm making it in preparation for threading through more
errors in the Swift language plugin.
2024-06-20 10:32:06 -07:00
Miro Bucko
265589785c
[nfc][lldb] Move FastSearch from CommandObjectMemoryFind to Process (#93688)
Moving CommandObjectMemoryFind::FastSearch() to Process::FindInMemory(). Plan to expose FindInMemory as public API in SBProcess.
2024-05-29 10:37:57 -07:00
GeorgeHuyubo
5bf653ca42
Revert "Read and store gnu build id from loaded core file" (#92181)
Reverts llvm/llvm-project#92078
2024-05-14 14:36:17 -07:00
GeorgeHuyubo
536abf827b
Read and store gnu build id from loaded core file (#92078)
As we have debuginfod as symbol locator available in lldb now, we want
to make full use of it.
In case of post mortem debugging, we don't always have the main
executable available.
However, the .note.gnu.build-id of the main executable(some other
modules too), should be available in the core file, as those binaries
are loaded in memory and dumped in the core file.

We try to iterate through the NT_FILE entries, read and store the gnu
build id if possible. This will be very useful as this id is the unique
key which is needed for querying the debuginfod server.

Test:
Build and run lldb. Breakpoint set to
https://github.com/llvm/llvm-project/blob/main/lldb/source/Plugins/SymbolLocator/Debuginfod/SymbolLocatorDebuginfod.cpp#L147
Verified after this commit, module_uuid is the correct gnu build id of
the main executable which caused the crash(first in the NT_FILE entry)
2024-05-14 14:35:35 -07:00
Kazu Hirata
744f38913f [lldb] Use StringRef::{starts,ends}_with (NFC)
This patch replaces uses of StringRef::{starts,ends}with with
StringRef::{starts,ends}_with for consistency with
std::{string,string_view}::{starts,ends}_with in C++20.

I'm planning to deprecate and eventually remove
StringRef::{starts,ends}with.
2023-12-16 14:39:37 -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
Pete Lawrence
92d8a28cc6
[lldb] Part 2 of 2 - Refactor CommandObject::DoExecute(...) return void (not bool) (#69991)
[lldb] Part 2 of 2 - Refactor `CommandObject::DoExecute(...)` to return
`void` instead of ~~`bool`~~

Justifications:
- The code doesn't ultimately apply the `true`/`false` return values.
- The methods already pass around a `CommandReturnObject`, typically
with a `result` parameter.
- Each command return object already contains:
	- A more precise status
	- The error code(s) that apply to that status

Part 1 refactors the `CommandObject::Execute(...)` method.
- See
[https://github.com/llvm/llvm-project/pull/69989](https://github.com/llvm/llvm-project/pull/69989)

rdar://117378957
2023-10-30 13:21:00 -07:00
Fangrui Song
678e3ee123 [lldb] Fix duplicate word typos; NFC
Those fixes were taken from https://reviews.llvm.org/D137338
2023-09-01 21:32:24 -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
Jonas Devlieghere
9cb3af1e86
[lldb] Fix bug introduced by fdbe7c7faa54
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
David Spickett
e6ec76c647 [LLDB] Apply FixCodeAddress to all forms of address arguments
This is a follow up to https://reviews.llvm.org/D141629
and applies the change it made to all paths through ToAddress
(now DoToAddress).

I have included the test from my previous attempt
https://reviews.llvm.org/D136938.

The initial change only applied fixing to addresses that
would parse as integers, so my test case failed. Since
ToAddress has multiple exit points, I've wrapped it into
a new method DoToAddress.

Now you can call ToAddress, it will call DoToAddress and
no matter what path you take, the address will be fixed.

For the memory tagging commands we actually want the full
address (to work out mismatches). So I added ToRawAddress
for that.

I have tested this on a QEMU AArch64 Linux system with
Memory Tagging, Pointer Authentication and Top Byte Ignore
enabled. By running the new test and all other tests in
API/linux/aarch64.

Some commands have had calls to the ABI plugin removed
as ToAddress now does this for them.

The "memory region" command still needs to use the ABI plugin
to detect the end of memory when there are non-address bits.

Reviewed By: jasonmolenda

Differential Revision: https://reviews.llvm.org/D142715
2023-02-13 10:15:52 +00:00
serge-sans-paille
984b800a03
Move from llvm::makeArrayRef to ArrayRef deduction guides - last part
This is a follow-up to https://reviews.llvm.org/D140896, split into
several parts as it touches a lot of files.

Differential Revision: https://reviews.llvm.org/D141298
2023-01-10 11:47:43 +01:00
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
Fangrui Song
f43886e7ba [lldb] llvm::Optional::value() && => operator*/operator->
std::optional::value() has undesired exception checking semantics and is
unavailable in older Xcode (see _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS). The
call sites block std::optional migration.
2022-12-17 20:37:13 +00:00
David Spickett
c831cea5ef [LLDB] Fix "memory region --all" when there is no ABI plugin
There are two conditions for the loop exit. Either we hit LLDB_INVALID_ADDRESS
or the ABI tells us we are beyond mappable memory.

I made a mistake in that second part that meant if you had no ABI plugin
--all would stop on the first loop and return nothing.

If there's no ABI plugin we should only check for LLDB_INVALID_ADDRESS.

Depends on D134029

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D134030
2022-09-23 12:32:38 +00:00
David Spickett
ee582001bf [LLDB] Properly return errors from "memory region --all"
When I wrote the initial version I forgot that a region being
unmapped is not an error. There are real errors that we don't
want to hide, such as the remote not supporting the
qMemoryRegionInfo packet (gdbserver does not).

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D134029
2022-09-23 12:32:12 +00:00
Fangrui Song
59d2495fe2 [lldb] LLVM_FALLTHROUGH => [[fallthrough]]. NFC 2022-08-08 11:31:49 -07:00
Kazu Hirata
1d9231de70 [lldb] Remove redundant member initialization (NFC)
Identified with readability-redundant-member-init.
2022-07-24 12:27:09 -07:00
Slava Gurevich
459cfa5e94 [LLDB][NFC][Reliability] Fix uninitialized variables from Coverity scan
Improve LLDB reliability by fixing the following "uninitialized variables" static code inspection warnings from
scan.coverity.com:

1094796 1095721 1095728 1095737 1095741
1095756 1095779 1095789 1095805 1214552
1229457 1232475 1274006 1274010 1293427
1364800 1364802 1364804 1364812 1364816
1374902 1374909 1384975 1399312 1420451
1431704 1454230 1454554 1454615 1454579
1454594 1454832 1457759 1458696 1461909
1467658 1487814 1487830 1487845

Differential Revision: https://reviews.llvm.org/D130098
2022-07-20 14:50:48 -07:00
Kazu Hirata
5cff5142a8 Use value instead of getValue (NFC) 2022-07-15 20:03:13 -07:00
Jonas Devlieghere
7ced9fff95
[lldb] Refactor command option enum values (NFC)
Refactor the command option enum values and the command argument table
to connect the two. This has two benefits:

 - We guarantee that two options that use the same argument type have
   the same accepted values.
 - We can print the enum values and their description in the help
   output. (D129707)

Differential revision: https://reviews.llvm.org/D129703
2022-07-14 21:18:07 -07:00
Kazu Hirata
96d1b4ddb2 [lld] Don't use Optional::hasValue (NFC)
This patch replaces x.hasValue() with x where x is contextually
convertible to bool.
2022-06-26 19:29:40 -07:00
Kazu Hirata
3b7c3a654c Revert "Don't use Optional::hasValue (NFC)"
This reverts commit aa8feeefd3ac6c78ee8f67bf033976fc7d68bc6d.
2022-06-25 11:56:50 -07:00
Kazu Hirata
aa8feeefd3 Don't use Optional::hasValue (NFC) 2022-06-25 11:55:57 -07:00
Kazu Hirata
ed8fceaa09 Don't use Optional::getValue (NFC) 2022-06-20 23:35:53 -07:00
Chelsea Cassanova
0f02dd34f2 [lldb/Commands] Prevent crash due to reading memory from page zero.
Adds a check to ensure that a process exists before attempting to get
its ABI to prevent lldb from crashing due to trying to read from page zero.

Differential revision: https://reviews.llvm.org/D127016
2022-06-08 18:10:41 -04:00
David Spickett
068f14f1e4 [lldb] Add --show-tags option to "memory find"
This is off by default. If you get a result and that
memory has memory tags, when --show-tags is given you'll
see the tags inline with the memory content.

```
(lldb) memory read mte_buf mte_buf+64 --show-tags
<...>
0xfffff7ff8020: 00 00 00 00 00 00 00 00 0d f0 fe ca 00 00 00 00 ................ (tag: 0x2)
<...>
(lldb) memory find -e 0xcafef00d mte_buf mte_buf+64 --show-tags
data found at location: 0xfffff7ff8028
0xfffff7ff8028: 0d f0 fe ca 00 00 00 00 00 00 00 00 00 00 00 00 ................ (tags: 0x2 0x3)
0xfffff7ff8038: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ (tags: 0x3 0x4)
```

The logic for handling alignments is the same as for memory read
so in the above example because the line starts misaligned to the
granule it covers 2 granules.

Depends on D125089

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D125090
2022-05-19 14:40:01 +01:00
David Spickett
13e1cf8065 Reland "[lldb] Add --all option to "memory region""
This reverts commit 3e928c4b9dfb01efd2cb968795e605760828e873.

This fixes an issue seen on Windows where we did not properly
get the section names of regions if they overlapped. Windows
has regions like:
[0x00007fff928db000-0x00007fff949a0000) ---
[0x00007fff949a0000-0x00007fff949a1000) r-- PECOFF header
[0x00007fff949a0000-0x00007fff94a3d000) r-x .hexpthk
[0x00007fff949a0000-0x00007fff94a85000) r-- .rdata
[0x00007fff949a0000-0x00007fff94a88000) rw- .data
[0x00007fff949a0000-0x00007fff94a94000) r-- .pdata
[0x00007fff94a94000-0x00007fff95250000) ---

I assumed that you could just resolve the address and get the section
name using the start of the region but here you'd always get
"PECOFF header" because they all have the same start point.

The usual command repeating loop used the end address of the previous
region when requesting the next, or getting the section name.
So I've matched this in the --all scenario.

In the example above, somehow asking for the region at
0x00007fff949a1000 would get you a region that starts at
0x00007fff949a0000 but has a different end point. Using the load
address you get (what I assume is) the correct section name.
2022-05-19 13:16:36 +01:00
David Spickett
29e556fc2b [lldb] Change implementation of memory read --show-tags option
This does 2 things:
* Moves it after the short options. Which makes sense given it's
  a niche, default off option.
  (if 2 files for one option seems a bit much, I am going to reuse
  them for "memory find" later)
* Fixes the use of repeated commands. For example:
    memory read buf --show-tags
    <shows tags>
    memory read
    <shows tags>

Added tests for the repetition and updated existing help tests.

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D125089
2022-05-18 16:49:09 +01:00
David Spickett
3e928c4b9d Revert "[lldb] Add --all option to "memory region""
This reverts commit 8e648f195c3d57e573fdd8023edcfd80e0516c61
due to test failures on Windows:
https://lab.llvm.org/buildbot/#/builders/83/builds/19094
2022-05-18 11:57:20 +00:00
David Spickett
8e648f195c [lldb] Add --all option to "memory region"
This adds an option to the memory region command
to print all regions at once. Like you can do by
starting at address 0 and repeating the command
manually.

memory region [-a] [<address-expression>]

(lldb) memory region --all
[0x0000000000000000-0x0000000000400000) ---
[0x0000000000400000-0x0000000000401000) r-x <...>/a.out PT_LOAD[0]
<...>
[0x0000fffffffdf000-0x0001000000000000) rw- [stack]
[0x0001000000000000-0xffffffffffffffff) ---

The output matches exactly what you'd get from
repeating the command. Including that it shows
unmapped areas between the mapped regions.

(this is why Process GetMemoryRegions is not
used, that skips unmapped areas)

Help text has been updated to show that you can have
an address or --all but not both.

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D111791
2022-05-18 10:33:39 +00:00
David Spickett
b809c4cdb7 [lldb] Add FixAnyAddress to ABI plugins
FixAnyAddress is to be used when we don't know or don't care
whether we're fixing a code or data address.

By using FixAnyAddress over the others, you document that no
specific choice was made.

On all existing platforms apart from Arm Thumb, you could use
either FixCodeAddress or FixDataAddress and be fine. Up until
now I've chosen to use FixDataAddress but if I had
chosen to use FixCodeAddress that would have broken Arm Thumb.

Hence FixAnyAddress, to give you the "safest" option when you're
in generic code.

Uses of FixDataAddress in memory region code have been changed
to FixAnyAddress. The functionality is unchanged.

Reviewed By: omjavaid, JDevlieghere

Differential Revision: https://reviews.llvm.org/D124000
2022-04-28 14:57:40 +01:00
David Spickett
68e73eaee6 [lldb] Handle empty search string in "memory find"
Given that you'd never find empty string, just error.

Also add a test that an invalid expr generates an error.

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D123793
2022-04-19 09:19:38 +00:00
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
Jonas Devlieghere
2165c36be4
[lldb] Return a DataBuffer from FileSystem::CreateDataBuffer (NFC)
The concrete class (DataBufferLLVM) is an implementation detail.
2022-04-01 17:31:20 -07:00
Shafik Yaghmour
24f9a2f53d [LLDB] Applying clang-tidy modernize-use-equals-default over LLDB
Applied modernize-use-equals-default clang-tidy check over LLDB.

This check is already present in the lldb/.clang-tidy config.

Differential Revision: https://reviews.llvm.org/D121844
2022-03-31 13:21:49 -07:00
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
Jim Ingham
635f03fe97 Add a repeat command option for "thread backtrace --count N".
This way if you have a long stack, you can issue "thread backtrace --count 10"
and then subsequent <Return>-s will page you through the stack.

This took a little more effort than just adding the repeat command, since
the GetRepeatCommand API was returning a "const char *".  That meant the command
had to keep the repeat string alive, which is inconvenient.  The original
API returned either a nullptr, or a const char *, so I changed the private API to
return an llvm::Optional<std::string>.  Most of the patch is propagating that change.

Also, there was a little thinko in fetching the repeat command.  We don't
fetch repeat commands for commands that aren't being added to history, which
is in general reasonable.  And we don't add repeat commands to the history -
also reasonable.  But we do want the repeat command to be able to generate
the NEXT repeat command.  So I adjusted the logic in HandleCommand to work
that way.

Differential Revision: https://reviews.llvm.org/D119046
2022-02-14 15:48:06 -08:00
David Spickett
2937b28218 Reland "[lldb] Remove non address bits when looking up memory regions"
This reverts commit 0df522969a7a0128052bd79182c8d58e00556e2f.

Additional checks are added to fix the detection of the last memory region
in GetMemoryRegions or repeating the "memory region" command when the
target has non-address bits.

Normally you keep reading from address 0, looking up each region's end
address until you get LLDB_INVALID_ADDR as the region end address.
(0xffffffffffffffff)

This is what the remote will return once you go beyond the last mapped region:
[0x0000fffffffdf000-0x0001000000000000) rw- [stack]
[0x0001000000000000-0xffffffffffffffff) ---

Problem is that when we "fix" the lookup address, we remove some bits
from it. On an AArch64 system we have 48 bit virtual addresses, so when
we fix the end address of the [stack] region the result is 0.
So we loop back to the start.

[0x0000fffffffdf000-0x0001000000000000) rw- [stack]
[0x0000000000000000-0x0000000000400000) ---

To fix this I added an additional check for the last range.
If the end address of the region is different once you apply
FixDataAddress, we are at the last region.

Since the end of the last region will be the last valid mappable
address, plus 1. That 1 will be removed by the ABI plugin.

The only side effect is that on systems with non-address bits, you
won't get that last catch all unmapped region from the max virtual
address up to 0xf...f.

[0x0000fffff8000000-0x0000fffffffdf000) ---
[0x0000fffffffdf000-0x0001000000000000) rw- [stack]
<ends here>

Though in some way this is more correct because that region is not
just unmapped, it's not mappable at all.

No extra testing is needed because this is already covered by
TestMemoryRegion.py, I simply forgot to run it on system that had
both top byte ignore and pointer authentication.

This change has been tested on a qemu VM with top byte ignore,
memory tagging and pointer authentication enabled.

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D115508
2022-02-10 10:42:49 +00:00
David Spickett
070090d08e [lldb] Add option to show memory tags in memory read output
This adds an option --show-tags to "memory read".

(lldb) memory read mte_buf mte_buf+32 -f "x" -s8 --show-tags
0x900fffff7ff8000: 0x0000000000000000 0x0000000000000000 (tag: 0x0)
0x900fffff7ff8010: 0x0000000000000000 0x0000000000000000 (tag: 0x1)

Tags are printed on the end of each line, if that
line has any tags associated with it. Meaning that
untagged memory output is unchanged.

Tags are printed based on the granule(s) of memory that
a line covers. So you may have lines with 1 tag, with many
tags, no tags or partially tagged lines.

In the case of partially tagged lines, untagged granules
will show "<no tag>" so that the ordering is obvious.
For example, a line that covers 2 granules where the first
is not tagged:

(lldb) memory read mte_buf-16 mte_buf+16 -l32 -f"x" --show-tags
0x900fffff7ff7ff0: 0x00000000 <...> (tags: <no tag> 0x0)

Untagged lines will just not have the "(tags: ..." at all.
Though they may be part of a larger output that does have
some tagged lines.

To do this I've extended DumpDataExtractor to also print
memory tags where it has a valid execution context and
is asked to print them.

There are no special alignment requirements, simply
use "memory read" as usual. All alignment is handled
in DumpDataExtractor.

We use MakeTaggedRanges to find all the tagged memory
in the current dump, then read all that into a MemoryTagMap.

The tag map is populated once in DumpDataExtractor and re-used
for each subsequently printed line (or recursive call of
DumpDataExtractor, which some formats do).

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D107140
2022-01-26 14:40:39 +00:00
David Spickett
7d19566c3b [lldb] Ignore non-address bits in "memory find" arguments
This removes the non-address bits before we try to use
the addresses.

Meaning that when results are shown, those results won't
show non-address bits either. This follows what "memory read"
has done. On the grounds that non-address bits are a property
of a pointer, not the memory pointed to.

I've added testing and merged the find and read tests into one
file.

Note that there are no API side changes because "memory find"
does not have an equivalent API call.

Reviewed By: omjavaid

Differential Revision: https://reviews.llvm.org/D117299
2022-01-24 10:42:49 +00:00
Kazu Hirata
abb0ed4495 [Commands] Remove redundant member initialization (NFC)
Identified with readability-redundant-member-init.
2022-01-23 11:07:14 -08:00
David Spickett
88fdce5be6 [lldb] Remove non address bits from memory read arguments
Addresses on AArch64 can have top byte tags, memory tags and pointer
authentication signatures in the upper bits.

While testing memory tagging I found that memory read couldn't
read a range if the two addresses had different tags. The same
could apply to signed pointers given the right circumstance.

(lldb) memory read mte_buf_alt_tag mte_buf+16
error: end address (0x900fffff7ff8010) must be greater than the start
address (0xa00fffff7ff8000).

Or it would try to read a lot more memory than expected.

(lldb) memory read mte_buf mte_buf_alt_tag+16
error: Normally, 'memory read' will not read over 1024 bytes of data.
error: Please use --force to override this restriction just once.
error: or set target.max-memory-read-size if you will often need a
larger limit.

Fix this by removing non address bits before we calculate the read
range. A test is added for AArch64 Linux that confirms this by using
the top byte ignore feature.

This means that if you do read with a tagged pointer the output
does not include those tags. This is potentially confusing but I think
overall it's better that we don't pretend that we're reading memory
from a range that the process is unable to map.

(lldb) p ptr1
(char *) $4 = 0x3400fffffffff140 "\x80\xf1\xff\xff\xff\xff"
(lldb) p ptr2
(char *) $5 = 0x5600fffffffff140 "\x80\xf1\xff\xff\xff\xff"
(lldb) memory read ptr1 ptr2+16
0xfffffffff140: 80 f1 ff ff ff ff 00 00 38 70 bc f7 ff ff 00 00  ........8p......

Reviewed By: omjavaid, danielkiss

Differential Revision: https://reviews.llvm.org/D103626
2022-01-11 13:24:09 +00:00
David Spickett
3a870bffb1 [lldb] Add missing space in C string format memory read warning
Also add tests to check that we print the warning in the right
circumstances.

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D114877
2021-12-08 11:20:25 +00:00
Venkata Ramanaiah Nalamothu
7f05ff8be4 [Bug 49018][lldb] Fix incorrect help text for 'memory write' command
Certain commands like 'memory write', 'register read' etc all use
the OptionGroupFormat options but the help usage text for those
options is not customized to those commands.

One such example is:

  (lldb) help memory read
           -s <byte-size> ( --size <byte-size> )
               The size in bytes to use when displaying with the selected format.
  (lldb) help memory write
	   -s <byte-size> ( --size <byte-size> )
               The size in bytes to use when displaying with the selected format.

This patch allows such commands to overwrite the help text for the options
in the OptionGroupFormat group as needed and fixes help text of memory write.

llvm.org/pr49018.

Reviewed By: DavidSpickett

Differential Revision: https://reviews.llvm.org/D114448
2021-11-26 19:14:26 +05:30
Venkata Ramanaiah Nalamothu
94038c570f [lldb] Fix 'memory write' to not allow specifying values when writing file contents
Currently the 'memory write' command allows specifying the values when
writing the file contents to memory but the values are actually ignored. This
patch fixes that by erroring out when values are specified in such cases.

Reviewed By: DavidSpickett

Differential Revision: https://reviews.llvm.org/D114544
2021-11-26 15:50:36 +05:30
Michał Górny
14735cab65 [lldb] [gdb-remote] Add eOpenOptionReadWrite for future gdb compat
Modify OpenOptions enum to open the future path into synchronizing
vFile:open bits with GDB.  Currently, LLDB and GDB use different flag
models effectively making it impossible to match bits.  Notably, LLDB
uses two bits to indicate read and write status, and uses union of both
for read/write.  GDB uses a value of 0 for read-only, 1 for write-only
and 2 for read/write.

In order to future-proof the code for the GDB variant:

1. Add a distinct eOpenOptionReadWrite constant to be used instead
   of (eOpenOptionRead | eOpenOptionWrite) when R/W access is required.

2. Rename eOpenOptionRead and eOpenOptionWrite to eOpenOptionReadOnly
   and eOpenOptionWriteOnly respectively, to make it clear that they
   do not mean to be combined and require update to all call sites.

3. Use the intersection of all three flags when matching against
   the three possible values.

This commit does not change the actual bits used by LLDB.

Differential Revision: https://reviews.llvm.org/D106984
2021-08-09 12:06:59 +02:00