Summary:
This argument was added back in 2010 (r118882) to support the ability to unwind
from functions whose eh_frame entry does not cover the entire range of
the function.
However, due to the caching happening in FuncUnwinders, this solution is
very fragile. FuncUnwinders will cache the plan it got from eh_frame
regardless of the value of the current_offset, so our ability to unwind
from a given function depended what was the value of "current_offset" the
first time that this function was called.
Furthermore, since the "image show-unwind" command did not know what's
the right offset to pass, this created an unfortunate situation where
"image show-unwind" would show no valid plans for a function, even
though they were available and being used.
In this patch I implement the feature slightly differently. Instead of
giving just a base address to the eh_frame unwinder, I give it the
entire range we are interested in. Then, I change the unwinder to return
the first plan that covers (even partially) that range. This way even a
partial plan will be returned, regardless of the address in the function
where we are stopped at.
This solution is still not 100% correct, as it will not handle a
function which is covered by two independent fde entries. However, I
don't expect anybody will write this kind of functions, and this wasn't
handled by the previous implementation either. If this is ever needed in
the future. The eh_frame unwinder can be extended to return "composite"
unwind plans created by merging sevelar fde entries.
I also create a test which triggers this scenario. As doing this is
virtually impossible without hand-written assembly, the test only works
on x86 linux.
Reviewers: jasonmolenda, clayborg
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D60829
llvm-svn: 358964
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
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
Summary:
instead of returning the architecture through by-ref argument and a
boolean value indicating success, we can just return the ArchSpec
directly. Since the ArchSpec already has an invalid state, it can be
used to denote the failure without the additional bool.
Reviewers: clayborg, zturner, espindola
Subscribers: emaste, arichardson, JDevlieghere, lldb-commits
Differential Revision: https://reviews.llvm.org/D56129
llvm-svn: 350291
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 $PWD
Differential revision: https://reviews.llvm.org/D55584
llvm-svn: 349215
This is intended as a clean up after the big clang-format commit
(r280751), which unfortunately resulted in many of the comment
paragraphs in LLDB being very hard to read.
FYI, the script I used was:
import textwrap
import commands
import os
import sys
import re
tmp = "%s.tmp"%sys.argv[1]
out = open(tmp, "w+")
with open(sys.argv[1], "r") as f:
header = ""
text = ""
comment = re.compile(r'^( *//) ([^ ].*)$')
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
Summary:
The classes have no dependencies, and they are used both by lldb and
lldb-server, so it makes sense for them to live in the lowest layers.
Reviewers: zturner, jingham
Subscribers: emaste, mgorny, lldb-commits
Differential Revision: https://reviews.llvm.org/D34746
llvm-svn: 306682
Summary:
instead of using a boolean to differentiate between the two section
types, use an enum to make the intent clearer.
I also remove the RegisterKind argument from the constructor, as this
can be deduced from the Type argument.
Reviewers: clayborg, jasonmolenda
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D34681
llvm-svn: 306521
Summary:
This is a beefed-up version of D33504, which adds support for dwarf 4
debug_frame section format.
The main difference here is that the decision whether to use eh_frame or
debug_frame is done on a per-function basis instead of per-object file.
This is necessary because one module can contain both sections (for
example, the start files added by the linker will typically pull in
eh_frame), but we want to be able to access both, for maximum
information.
I also add unit test for parsing various CFI formats (eh_frame,
debug_frame v3 and debug_frame v4).
Reviewers: jasonmolenda, clayborg
Subscribers: mgorny, aprantl, abidh, lldb-commits, tatyana-krasnukha
Differential Revision: https://reviews.llvm.org/D34613
llvm-svn: 306397
This reverts commit r303847 as it introduces a number of regressions.
Investigation has showed that we are parsing the CIE entries in the
debug_frame section incorrectly -- we are parsing them the same way as
eh_frame, but the entries in debug_frame have a couple of extra entries
which have not been taken into account.
llvm-svn: 303854
There are some differences between eh_frame and debug_frame formats that
are not considered by DWARFCallFrameInfo::GetFDEIndex. An FDE entry
contains CIE_pointer in debug_frame in same place as cie_id in eh_frame.
As described in dwarf standard (section 6.4.1), CIE_pointer is an
"offset into the .debug_frame section". So, variable cie_offset should
be equal cie_id for debug_frame.
FDE entries with zeroth CIE pointer (which is actually placed in cie_id
variable) shouldn't be ignored also.
I have also added a little change which allow to use debug_info section
when eh_frame is absent. This case really can take place on some platforms.
Patch from tatyana-krasnukha.
https://reviews.llvm.org/D33504
llvm-svn: 303847
The Timer destructor would grab a global mutex in order to update
execution time. Add a class to define a category once, statically; the
class adds itself to an atomic singly linked list, and thus subsequent
updates only need to use an atomic rather than grab a lock and perform a
hashtable lookup.
Differential Revision: https://reviews.llvm.org/D32823
Patch by Scott Smith <scott.smith@purestorage.com>.
llvm-svn: 303058
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
*** to conform to clang-format’s LLVM style. This kind of mass change has
*** two obvious implications:
Firstly, merging this particular commit into a downstream fork may be a huge
effort. Alternatively, it may be worth merging all changes up to this commit,
performing the same reformatting operation locally, and then discarding the
merge for this particular commit. The commands used to accomplish this
reformatting were as follows (with current working directory as the root of
the repository):
find . \( -iname "*.c" -or -iname "*.cpp" -or -iname "*.h" -or -iname "*.mm" \) -exec clang-format -i {} +
find . -iname "*.py" -exec autopep8 --in-place --aggressive --aggressive {} + ;
The version of clang-format used was 3.9.0, and autopep8 was 1.2.4.
Secondly, “blame” style tools will generally point to this commit instead of
a meaningful prior commit. There are alternatives available that will attempt
to look through this change and find the appropriate prior commit. YMMV.
llvm-svn: 280751
It's always hard to remember when to include this file, and
when you do include it it's hard to remember what preprocessor
check it needs to be behind, and then you further have to remember
whether it's windows.h or win32.h which you need to include.
This patch changes the name to PosixApi.h, which is more appropriately
named, and makes it independent of any preprocessor setting.
There's still the issue of people not knowing when to include this,
because there's not a well-defined set of things it exposes other
than "whatever is missing on Windows", but at least this should
make it less painful to fix when problems arise.
This patch depends on LLVM revision r278170.
llvm-svn: 278177
Summary:
This adds the knowledge of the DW_CFA_GNU_args_size instruction to the eh_frame parsing code.
Right now it is ignored as I am unsure how is it supposed to be handled, but now we are at least
able to parse the rest of the FDE containing this instruction.
I also add a fix for a bug which was exposed by this instruction. Namely, a mismatched sequence
of remember/restore instructions in the input could cause us to pop an empty stack and crash. Now
we just log the error and ignore the offending instruction.
Reviewers: jasonmolenda
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D22266
llvm-svn: 275260
as an asynchronous unwind plan source.
Two small fixes to the compact unwind dumper tool for
armv7 encodings.
A change to DWARFCallFrameInfo to strip the 0th bit on
addresses in eh_frame sections when armv7. In the
clang generated examples I have, the 0th bit is set for
thumb functions and that's causing the unwinder to pick
the wrong function for eh_frame info.
llvm-svn: 271970
* Generate artificial symbol names from eh_fame during symbol parsing
so these symbols are already present when we calcualte the size of
the symbols where 0 is specified.
* Fix symbol size calculation for the last symbol in the file where
it have to last until the end of the parent section.
This is the re-commit of the original change after fixing some test
failures on OSX.
Differential revision: http://reviews.llvm.org/D16996
llvm-svn: 261205
* Generate artificial symbol names from eh_fame during symbol parsing
so these symbols are already present when we calcualte the size of
the symbols where 0 is specified.
* Fix symbol size calculation for the last symbol in the file where
it have to last until the end of the parent section.
Differential revision: http://reviews.llvm.org/D16996
llvm-svn: 260369
"gcc" register numbers are now correctly referred to as "ehframe"
register numbers. In almost all cases, ehframe and dwarf register
numbers are identical (the one exception is i386 darwin where ehframe
regnums were incorrect).
The old "gdb" register numbers, which I incorrectly thought were
stabs register numbers, are now referred to as "Process Plugin"
register numbers. This is the register numbering scheme that the
remote process controller stub (lldb-server, gdbserver, core file
support, kdp server, remote jtag devices, etc) uses to refer to the
registers. The process plugin register numbers may not be contiguous
- there are remote jtag devices that have gaps in their register
numbering schemes.
I removed all of the enums for "gdb" register numbers that we had
in lldb - these were meaningless - and I put LLDB_INVALID_REGNUM
in all of the register tables for the Process Plugin regnum slot.
This change is almost entirely mechnical; the one actual change in
here is to ProcessGDBRemote.cpp's ParseRegisters() which parses the
qXfer:features:read:target.xml response. As it parses register
definitions from the xml, it will assign sequential numbers as the
eRegisterKindLLDB numbers (the lldb register numberings must be
sequential, without any gaps) and if the xml file specifies register
numbers, those will be used as the eRegisterKindProcessPlugin
register numbers (and those may have gaps). A J-Link jtag device's
target.xml does contain a gap in register numbers, and it only
specifies the register numbers for the registers after that gap.
The device supports many different ARM boards and probably selects
different part of its register file as appropriate.
http://reviews.llvm.org/D12791
<rdar://problem/22623262>
llvm-svn: 247741
Previously we handled only a few opcode DWARF CFI opcode when we
were parsing the CIE. With this change we use mostly the same code
what we use for parsing the PDE which cover more opcode.
Differential revision: http://reviews.llvm.org/D10866
llvm-svn: 241332
The CFA offset shouldn't be irestored to the saved value in case
of a DW_CFA_restore_state opcode.
Differential revision: http://reviews.llvm.org/D10843
llvm-svn: 241331
Removed some unused variables, added some consts, changed some casts
to const_cast. I don't think any of these changes are very
controversial.
Differential Revision: http://reviews.llvm.org/D9674
llvm-svn: 237218
Summary: Just what it says on the box.
Reviewers: jasonmolenda
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D9150
llvm-svn: 235493
Summary:
This patch enables evaluation of DWARF expressions setting the CFA during stack unwinding.
This makes TestSigtrampUnwind "almost" pass on linux. I am not enabling the test yet since the
symbol name for the signal trampoline does not get resolved properly due to a different bug, but
apart from that, the backtrace is sane.
I am unsure how this change affects Mac. I think it makes the unwinder prefer the DWARF unwind
plan instead of some custom platform-dependant plan. However, it does not affect the end result
- the stack unwinding works as expected.
Reviewers: jasonmolenda
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D7792
llvm-svn: 230211
Summary:
This change refactors UnwindPlan::Row to be able to store the fact that the CFA is value is set
by evaluating a dwarf expression (DW_CFA_def_cfa_expression). This is achieved by creating a new
class CFAValue and moving all CFA setting/getting code there. Note that code using the new
CFAValue::isDWARFExpression is not yet present and will be added in a follow-up patch. Therefore,
this patch should not change the functionality in any way.
Test Plan: Ran tests on Mac and Linux. No regressions detected.
Reviewers: jasonmolenda, clayborg
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D7755
llvm-svn: 230210
eh_frame data. These two pieces of information are used in the
process of exception handler unwinding on SysV ABI systems.
This patch reads the data from the eh_frame section
(DWARFCallFrameInfo.cpp), allows for it to be saved & read out
of a given UnwindPlan (UnwindPlan.h, UnwindPlan.cpp) - as well
as printing the information in the UnwindPlan::Dump method - and
adds methods to the FuncUnwinders object so that higher levels
can query if a given function has an LSDA / personality routine
defined.
It's only lightly tested, but seems to be working correctly as long
as your have this information in eh_frame. Does not address getting
this information from compact unwind yet on Darwin systems.
<rdar://problem/18742797>
llvm-svn: 222214
In practice, 64bit eh_frame is not used even for x86_64 binaries. The main reason is in eh_frame we almost always use pc-relative addressing, so addresses are within 32bits and gcc just sticks to 32bit eh_frame.
I generated 64bit eh_frame for Android Java runtime and unwind successfully in gdb, and in lldb with this patch.
Patch by Tong Shen.
llvm-svn: 216409
in LLDB that load the canonical frame address rather than a location list.
- Handles the simple case where a CFA can be pulled from the current stack frame.
- Fixes more than one hundred failing tests with gcc 4.8!
TODO: Use UnwindPlan::GetRowForFunctionOffset if the DWARFExpression needs
to be evaluated in a context analogous to a virtual unwind (perhaps using RegisterContextLLDB).
- Also adds some comments to DWARFCallFrameInfo whenever I got confused.
llvm-svn: 187361
LLDB is crashing when logging is enabled from lldb-perf-clang. This has to do with the global destructor chain as the process and its threads are being torn down.
All logging channels now make one and only one instance that is kept in a global pointer which is never freed. This guarantees that logging can correctly continue as the process tears itself down.
llvm-svn: 178191
DWARFCallFrameInfo method which returns a RangeVector pre-size the
vector based on the number of entries it will be adding insted of
growing the vector as items are added.
llvm-svn: 177773
This returns a vector of <file address, size> entries for all of
the functions in the module that have an eh_frame FDE.
Update ObjectFileMachO to use the eh_frame FDE function addresses if
the LC_FUNCTION_STARTS section is missing, to fill in the start
addresses of any symbols that have been stripped from the binary.
Generally speaking, lldb works best if it knows the actual start
address of every function in a module - it's especially important
for unwinding, where lldb inspects the instructions in the prologue
of the function. In a stripped binary, it is deprived of this
information and it reduces the quality of our unwinds and saved
register retrieval.
Other ObjectFile users may want to use the function addresses from
DWARFCallFrameInfo to fill in any stripped symbols like ObjectFileMachO
does already.
<rdar://problem/13365659>
llvm-svn: 177624
track the EH FDEs for the functions in a module to using a
RangeDataVector, a more light-weight data structure that only refers
to File addresses. Makes the initial FDE scan about 3x faster, uses
less memory.
<rdar://problem/13465650>
llvm-svn: 177585
Major fixed to allow reading files that are over 4GB. The main problems were that the DataExtractor was using 32 bit offsets as a data cursor, and since we mmap all of our object files we could run into cases where if we had a very large core file that was over 4GB, we were running into the 4GB boundary.
So I defined a new "lldb::offset_t" which should be used for all file offsets.
After making this change, I enabled warnings for data loss and for enexpected implicit conversions temporarily and found a ton of things that I fixed.
Any functions that take an index internally, should use "size_t" for any indexes and also should return "size_t" for any sizes of collections.
llvm-svn: 173463
Full UnwindPlan is trying to do an impossible unwind; in that case
invalidate the Full UnwindPlan and replace it with the architecture
default unwind plan.
This is a scenario that happens occasionally with arm unwinds in
particular; the instruction analysis based full unwindplan can
mis-parse the functions and the stack walk stops prematurely. Now
we can do a simpleminded frame-chain walk to find the caller frame
and continue the unwind. It's not ideal but given the complicated
nature of analyzing the arm functions, and the lack of eh_frame
information on iOS, it is a distinct improvement and fixes some
long-standing problems with the unwinder on that platform.
This is fixing <rdar://problem/12091421>. I may re-use this
invalidate feature in the future if I can identify other cases where
the full unwindplan's unwind information is clearly incorrect.
This checkin also includes some cleanup for the volatile register
definition in the arm ABI plugin for <rdar://problem/10652166>
although work remains to be done for that bug.
llvm-svn: 166757
Alex Langford