Summary:
This fixes a bug in the logic for choosing the unwind plan. Based on the
comment in UnwindAssembly-x86, the intention was that a plan which
describes the function epilogue correctly does not need to be augmented
(and it should be used directly). However, the way this was implemented
(by returning false) meant that the higher level code
(FuncUnwinders::GetEHFrameAugmentedUnwindPlan) interpreted this as a
failure to produce _any_ plan and proceeded with other fallback options.
The fallback usually chosed for "asynchronous" plans was the
"instruction emulation" plan, which tended to fall over on certain
functions with multiple epilogues (that's a separate bug).
This patch simply changes the function to return true, which signals the
caller that the unmodified plan is ready to be used.
The attached test case demonstrates the case where we would previously
fall back to the instruction emulation plan, and unwind incorrectly --
the test asserts that the "augmented" eh_frame plan is used, and that
the unwind is correct.
Reviewers: jasonmolenda, jankratochvil
Subscribers: davide, echristo, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D82378
Fix a bug where UnwindAssemblyInstEmulation would confuse which
register is used to compute the Canonical Frame Address after it
had branched over a mid-function epilogue (where the CFA reg changes
from $fp to $sp in the process of epiloguing). Reinstate the
correct CFA register after we forward the unwind rule for branch
targets. The failure mode was that UnwindAssemblyInstEmulation
would think CFA was set in terms of $sp after one of these epilogues,
and if it sees modifications to $sp after the branch target, it would
change the CFA offset in the unwind rule -- even though the CFA is
defined in terms of $fp and the $sp changes are irrelevant to correct
calculation.
<rdar://problem/60300528>
Differential Revision: https://reviews.llvm.org/D78077
LLDB has a few different styles of header guards and they're not very
consistent because things get moved around or copy/pasted. This patch
unifies the header guards across LLDB and converts everything to match
LLVM's style.
Differential revision: https://reviews.llvm.org/D74743
Use LLDB_PLUGIN_DEFINE_ADV to make the name of the generated initializer
match the name of the plugin. This is a step towards generating the
initializers with a def file. I'm landing this change in pieces so I can
narrow down what exactly breaks the Windows bot.
This patch changes the way we initialize and terminate the plugins in
the system initializer. It uses an approach similar to LLVM's
TARGETS_TO_BUILD with a def file that enumerates the plugins.
The previously landed patch got reverted because it was lacking:
(1) A plugin definition for the Objective-C language runtime,
(2) The dependency between the Static and WASM dynamic loader,
(3) Explicit initialization of ScriptInterpreterNone for lldb-test.
All issues have been addressed in this patch.
Differential revision: https://reviews.llvm.org/D73067
This patch changes the way we initialize and terminate the plugins in
the system initializer. It uses an approach similar to LLVM's
TARGETS_TO_BUILD with a def file that enumerates the plugins.
Differential revision: https://reviews.llvm.org/D73067
This is a step towards making the initialize and terminate calls be
generated by CMake, which in turn is towards making it possible to
disable plugins at configuration time.
Differential revision: https://reviews.llvm.org/D74245
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
Unwind plan augmentation should compute the plan row at offset x from
the instruction before offset x, but currently we compute it from the
instruction at offset x. Note that this behavior is a regression
introduced when moving the x86 assembly inspection engine to its own
file
(1c9858b298 (diff-375a2be066db6f34bb9a71442c9b71fcL913));
the original version handled this properly by copying the previous
instruction out before advancing the instruction pointer.
The relevant bug with more info is here: https://bugs.llvm.org/show_bug.cgi?id=43561
Differential Revision: https://reviews.llvm.org/D68454
Patch by Jaroslav Sevcik <jarin@google.com>.
llvm-svn: 374342
Summary:
Add __kernel_rt_sigreturn to the list of trap handlers for Linux (it's
used as such on aarch64 at least), and __restore_rt as well (used on
x86_64).
Skip decrement-and-recompute for trap handlers in
InitializeNonZerothFrame, as signal dispatch may point the child frame's
return address to the start of the return trampoline.
Parse the 'S' flag for signal handlers from eh_frame augmentation, and
propagate it to the unwind plan.
Reviewers: labath, jankratochvil, compnerd, jfb, jasonmolenda
Reviewed By: jasonmolenda
Subscribers: clayborg, MaskRay, wuzish, nemanjai, kbarton, jrtc27, atanasyan, jsji, javed.absar, kristof.beyls, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D63667
llvm-svn: 366580
The x86 assembly inspection engine has code to support detecting a
mid-function epilogue that ends in a RET instruction; add support for
recognizing an epilogue that ends in a JMP, and add a check that the
unwind state has been restored to the original stack setup; reinstate
the post-prologue unwind state after this JMP instruction.
The assembly inspection engine used for other architectures,
UnwindAssemblyInstEmulation, detects mid-function epilogues by
tracking branch instructions within the function and "forwards"
the current unwind state to the targets of the branches. If
an epilogue unwinds the stack and exits, followed by a branch
target, we get back to the correct unwind state. The x86
unwinder should move to this same algorithm, or possibly even
look at implementing an x86 instruction emulation plugin and
get UnwindAssemblyInstEmulation to work for x86 too. I added
a branch instruction recognizier method that will be necessary
if we want to switch the algorithm.
Differential Revision: https://reviews.llvm.org/D62764
<rdar://problem/51074422>
llvm-svn: 362456
Summary:
NFC = [[ https://llvm.org/docs/Lexicon.html#nfc | Non functional change ]]
This commit is the result of modernizing the LLDB codebase by using
`nullptr` instread of `0` or `NULL`. See
https://clang.llvm.org/extra/clang-tidy/checks/modernize-use-nullptr.html
for more information.
This is the command I ran and I to fix and format the code base:
```
run-clang-tidy.py \
-header-filter='.*' \
-checks='-*,modernize-use-nullptr' \
-fix ~/dev/llvm-project/lldb/.* \
-format \
-style LLVM \
-p ~/llvm-builds/debug-ninja-gcc
```
NOTE: There were also changes to `llvm/utils/unittest` but I did not
include them because I felt that maybe this library shall be updated in
isolation somehow.
NOTE: I know this is a rather large commit but it is a nobrainer in most
parts.
Reviewers: martong, espindola, shafik, #lldb, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: arsenm, jvesely, nhaehnle, hiraditya, JDevlieghere, teemperor, rnkovacs, emaste, kubamracek, nemanjai, ki.stfu, javed.absar, arichardson, kbarton, jrtc27, MaskRay, atanasyan, dexonsmith, arphaman, jfb, jsji, jdoerfert, lldb-commits, llvm-commits
Tags: #lldb, #llvm
Differential Revision: https://reviews.llvm.org/D61847
llvm-svn: 361484
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
The `ap` suffix is a remnant of lldb's former use of auto pointers,
before they got deprecated. Although all their uses were replaced by
unique pointers, some variables still carried the suffix.
In r353795 I removed another auto_ptr remnant, namely redundant calls to
::get for unique_pointers. Jim justly noted that this is a good
opportunity to clean up the variable names as well.
I went over all the changes to ensure my find-and-replace didn't have
any undesired side-effects. I hope I didn't miss any, but if you end up
at this commit doing a git blame on a weirdly named variable, please
know that the change was unintentional.
llvm-svn: 353912
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
Summary: Replace 0xc9 (LEAVE) with 0xcb (RETF) in ret_pattern_p(). Also put 0xc3 first, since it is the most common form and will match first.
Reviewers: jasonmolenda
Reviewed By: jasonmolenda
Subscribers: labath, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D57928
llvm-svn: 353643
instructions
Summary: This patch makes `x86AssemblyInspectionEngine` to process zero value of
the `B` field of the `REX` prefix in a correct way for `PUSH` and `POP`
instructions. MSVC sometimes emits `pushq %rbp` instruction as `0x40 0x55`, and
it was not parsed correctly before.
Reviewers: jasonmolenda, labath
Reviewed By: jasonmolenda, labath
Subscribers: abidh, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D57745
llvm-svn: 353281
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
This patch simplifies boolean expressions acorss LLDB. It was generated
using clang-tidy with the following command:
run-clang-tidy.py -checks='-*,readability-simplify-boolean-expr' -format -fix $PWD
Differential revision: https://reviews.llvm.org/D55584
llvm-svn: 349215
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
Summary:
This patch fixes issues with a stack realignment.
MSVC maintains two frame pointers (`ebx` and `ebp`) for a realigned stack - one
is used for access to function parameters, while another is used for access to
locals. To support this the patch:
- adds an alternative frame pointer (`ebx`);
- considers stack realignment instructions (e.g. `and esp, -32`);
- along with CFA (Canonical Frame Address) which point to the position next to
the saved return address (or to the first parameter on the stack) introduces
AFA (Aligned Frame Address) which points to the position of the stack pointer
right after realignment. AFA is used for access to registers saved after the
realignment (see the test);
Here is an example of the code with the realignment:
```
struct __declspec(align(256)) OverAligned {
char c;
};
void foo(int foo_arg) {
OverAligned oa_foo = { 1 };
auto aaa_foo = 1234;
}
void bar(int bar_arg) {
OverAligned oa_bar = { 2 };
auto aaa_bar = 5678;
foo(1111);
}
int main() {
bar(2222);
return 0;
}
```
and here is the `bar` disassembly:
```
push ebx
mov ebx, esp
sub esp, 8
and esp, -100h
add esp, 4
push ebp
mov ebp, [ebx+4]
mov [esp+4], ebp
mov ebp, esp
sub esp, 200h
mov byte ptr [ebp-200h], 2
mov dword ptr [ebp-4], 5678
push 1111 ; foo_arg
call j_?foo@@YAXH@Z ; foo(int)
add esp, 4
mov esp, ebp
pop ebp
mov esp, ebx
pop ebx
retn
```
Reviewers: labath, zturner, jasonmolenda, stella.stamenova
Reviewed By: jasonmolenda
Subscribers: abidh, lldb-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D53435
llvm-svn: 345577
These three classes have no external dependencies, but they are used
from various low-level APIs. Moving them down to Utility improves
overall code layering (although it still does not break any particular
dependency completely).
The XCode project will need to be updated after this change.
Differential Revision: https://reviews.llvm.org/D49740
llvm-svn: 339127
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
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
The rationale here is that ArchSpec is used throughout the codebase,
including in places which should not depend on the rest of the code in
the Core module.
This commit touches many files, but most of it is just renaming of
#include lines. In a couple of cases, I removed the #include ArchSpec
line altogether, as the file was not using it. In one or two places,
this necessitated adding other #includes like lldb-private-defines.h.
llvm-svn: 318048
blocks of memory, and if the final bytes of that block look like a long
x86 instruction, it can cause the llvm disassembler to read past the end
of the buffer. Use the maximum allowed instruction length that we pass
to the llvm disassembler as a way to limit this to the size of the buffer.
An example of how to trigger this is when lldb does a function call, it
puts a breakpoint on the beginning of main() and uses that as the return
address from the function call. When we stop at that location, lldb may
try to find the first frame up the stack. Because this is on the first
instruction of a function, it will get the word-size value at the stack
pointer and assume that this was the caller's pc value. But this is random
stack memory and could point to anything - an object in memory, something
in the data section, whatever. And if we have a symbol for that thing,
we'll try to disassemble it.
This was leading to infrequent crashes in customer scenarios; figured out
what was happening with address sanitizer.
<rdar://problem/30463256>
llvm-svn: 307454
Summary:
The instruction pattern:
and $-16, %esp
sub $imm, %esp
...
lea imm(%ebp), %esp
appears when the compiler is realigning the stack (for example in
main(), or almost everywhere with -mstackrealign switch). The "and"
instruction is very difficult to model, but that's not necessary, as
these frames are always %ebp-based (the compiler also needs a way to
restore the original %esp). Therefore the plans we were generating for
these function were almost correct already. The only place we were doing
it wrong were the last instructions of the epilogue (usually just
"ret"), where we had to revert to %esp-based unwinding, as the %ebp had
been popped already.
This was wrong because our "distance of esp from cfa" counter had picked
up the "sub" instruction (and incremented the counter) but it had not
seen that the register was reset by the "lea" instruction.
This patch fixes that shortcoming, and adds a test for handling
functions like this.
I have not been able to tickle the compiler into producing a 64-bit
function with this pattern, but I don't see a reason why it couldn't
produce it, if it chose to, so I add a x86_64 test as well.
Reviewers: jasonmolenda, tberghammer
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D34750
llvm-svn: 306666
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
Add missing linkage of the lldbPluginUnwindAssemblyX86 to LLVMMCDisasm
library. This fixes the following build failure when linking against
shared libraries:
lib64/liblldbPluginUnwindAssemblyX86.a(x86AssemblyInspectionEngine.cpp.o):x86AssemblyInspectionEngine.cpp:function lldb_private::x86AssemblyInspectionEngine::instruction_length(unsigned char*, int&): error: undefined reference to 'LLVMDisasmInstruction'
lib64/liblldbPluginUnwindAssemblyX86.a(x86AssemblyInspectionEngine.cpp.o):x86AssemblyInspectionEngine.cpp:function lldb_private::x86AssemblyInspectionEngine::~x86AssemblyInspectionEngine(): error: undefined reference to 'LLVMDisasmDispose'
lib64/liblldbPluginUnwindAssemblyX86.a(x86AssemblyInspectionEngine.cpp.o):x86AssemblyInspectionEngine.cpp:function lldb_private::x86AssemblyInspectionEngine::x86AssemblyInspectionEngine(lldb_private::ArchSpec const&): error: undefined reference to 'LLVMCreateDisasm'
Differential Revision: https://reviews.llvm.org/D31369
llvm-svn: 298777
In an effort to move the various DataBuffer / DataExtractor
classes from Core -> Utility, we have to separate the low-level
functionality from the higher level functionality. Only a
few functions required anything other than reading/writing
raw bytes, so those functions are separated out into a
more appropriate area. Specifically, Dump() and DumpHexBytes()
are moved into free functions in Core/DumpDataExtractor.cpp,
and GetGNUEHPointer is moved into a static function in the
only file that it's referenced from.
Differential Revision: https://reviews.llvm.org/D30560
llvm-svn: 296910
All references to Host and Core have been removed, so this
class can now safely be lowered into Utility.
Differential Revision: https://reviews.llvm.org/D30559
llvm-svn: 296909
With this patch, the only dependency left is from Utility
to Host. After this is broken, Utility will finally be
standalone.
Differential Revision: https://reviews.llvm.org/D29909
llvm-svn: 295088
Pavel Labath