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
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
This moves the following classes from Core -> Utility.
ConstString
Error
RegularExpression
Stream
StreamString
The goal here is to get lldbUtility into a state where it has
no dependendencies except on itself and LLVM, so it can be the
starting point at which to start untangling LLDB's dependencies.
These are all low level and very widely used classes, and
previously lldbUtility had dependencies up to lldbCore in order
to use these classes. So moving then down to lldbUtility makes
sense from both the short term and long term perspective in
solving this problem.
Differential Revision: https://reviews.llvm.org/D29427
llvm-svn: 293941
unittests. If I have time, I'd like to see if I can write some
tests of the eh_frame augmentation which is a wholly separate code
path (it seems like maybe it should be rolled into the main instruction
scanning codepath, to be honest, and operate on the generated
UnwindPlan instead of bothering with raw instructions at all).
Outside the eh_frame augmentation, I'm comfortable that this unwind
generator is being tested well now.
llvm-svn: 283186
'push 0x20(%esp)' which clang can generate when emitting
-fomit-frame-pointer code for 32-bit.
Add a unit test program which includes this instruction.
Also fix a bug in the refactoring/rewrite of the x86 assembly
instruction profiler where I'd hard coded it as a 64-bit disassembler
instead of using the ArchSpec to pick a 32-bit or 64-bit disassembler
from llvm. When the disassembler would hit an instruction
that is invalid in 64-bit mode, it would stop disassembling the function.
This likely led to the TestSBData testsuite failure on linux with 32-bit
i386 and gcc-4.9; I'll test that in a bit.
The newly added unit test program is 32-bit i386 code and it includes
an instruction which is invalid in 64-bit mode so it will catch this.
<rdar://problem/28557876>
llvm-svn: 282991
a linux bot test failure. That one is fixed; hopefully there won't
be any others turned up this time.
The eh_frame augmentation code wasn't working right after the
reorg/rewrite of the classes. It works correctly now for the one
test that was failing - but we'll see what the test bots come up
with.
<rdar://problem/28509178>
llvm-svn: 282659
A testbot found a regression introduced in the testsuite with
the changes in r282565 on Ubuntu (TestStepNoDebug.ReturnValueTestCase).
I'll get this set up on an ubuntu box and figure out what is happening
there -- likely a problem with the eh_frame augmentation, which isn't
used on macosx.
llvm-svn: 282566
x86AssemblyInspectionEngine and the current UnwindAssembly_x86 to
allow for the core engine to be exercised by unit tests.
The UnwindAssembly_x86 class will have access to Targets, Processes,
Threads, RegisterContexts -- it will be working in the full lldb
environment.
x86AssemblyInspectionEngine is layered away from all of that, it is
given some register definitions and a bag of bytes to profile.
I wrote an initial unittest for a do-nothing simple x86_64/i386
function to start with. I'll be adding more.
The x86 assembly unwinder was added to lldb early in its bringup;
I made some modernization changes as I was refactoring the code
to make it more consistent with how we write lldb today.
I also added RegisterContextMinidump_x86_64.cpp to the xcode project
file so I can run the unittests from that.
The testsuite passes with this change, but there was quite a bit of
code change by the refactoring and it's possible there are some
issues. I'll be testing this more in the coming days, but it looks
like it is behaving correctly as far as I can tell with automated
testing.
<rdar://problem/28509178>
llvm-svn: 282565
*** 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
Summary:
This doesn't exist in other LLVM projects any longer and doesn't
do anything.
Reviewers: chaoren, labath
Subscribers: emaste, tberghammer, lldb-commits, danalbert
Differential Revision: http://reviews.llvm.org/D12586
llvm-svn: 246749
Summary: This aligns the library names used by the Makefile build to be the same as those create by the CMake build to make switching between the two easier. The only major difficulty was lldbHost which was one library in the CMake system and several in the Makefile system. Most of the other changes are trivial renames.
Reviewers: labath
Subscribers: emaste, tberghammer, lldb-commits
Differential Revision: http://reviews.llvm.org/D11154
llvm-svn: 242196
Gcc for android use the leal instruction to substract from the stack
pointer in the prologue of a function call. This patch add basic support
for evaluating this instruction to support stack unwinding on
android-x86.
Differential revision: http://reviews.llvm.org/D8583
llvm-svn: 233178
This continues the effort to reduce header footprint and improve
build speed by removing clang and other unnecessary headers
from Target.h. In one case, some headers were included solely
for the purpose of declaring a nested class in Target, which was
not needed by anybody outside the class. In this case the
definition and implementation of the nested class were isolated
in the .cpp file so the header could be removed.
llvm-svn: 231107
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
signed and unsigned types in comparisons.
For the text offset, use the addr_t type that is used elsewhere to get
these kinds of offsets, and which it is being compared against. This
seems to make things more consistent.
For the other, the numbers are clearly small and uninteresting, so just
cast them to the most boring 'int' type.
llvm-svn: 229085
saved/restored across a mid-function epilogue. We ignore
repeated push/pops of a register so once we saw one 'pop %rbp',
we'd ignore it the second time we saw it.
<rdar://problem/19417410>
llvm-svn: 225853
it will do the right thing on x86 routines with a mid-function
epilogue sequence (where the unwind rules need to be reinstalled
after the epilogue has completed).
<rdar://problem/19417410>
llvm-svn: 225773
which will verify if the eh_frame instructions include details about
the prologue or not. Both clang and gcc include prologue instructions
but there's no requirement for them to do so -- and I'm sure we'll
have to interoperate with a compiler that doesn't generate prologue
info at some point.
I don't have any compilers that omit the prologue instructions so the
testing was of the "makre sure augmented unwind info is still created".
With an eh_frame without prologue, this code should reject the
augmentation scheme altogether and we should fall back to using assembly
instruction profiling.
llvm-svn: 225771
step through the complete function looking for any epilogue
instructions. If we find an epilogue sequence, re-instate
the correct unwind instructions if there is more code past
that epilogue -- this will correctly handle an x86 function
with multiple epilogues in it.
NB there is still a bug with the "eh_frame augmented"
UnwindPlans and mid-function epilogues. Looking at that next.
<rdar://problem/18863406>
llvm-svn: 225770
it more generally available.
Add checks to UnwindAssembly_x86::AugmentUnwindPlanFromCallSite() so
that it won't try to augment an UnwindPlan that already describes
the function epilogue.
Add a test case for backtracing out of _sigtramp on Darwin systems.
This could probably be adapted to test the same thing on linux/bsd but
the function names of sigtramp and kill are probably platform
specific and I'm not sure what they should be.
llvm-svn: 225578
which registers have been spilled (saved to the stack) - and
if we see that same register being saved to the stack again,
don't record that, it's something specific to this stack frame.
I found a code sequence for i386 where clang did a push %esi
and then later in the function it did movl %esi, -0x7c(%ebp)
and that second save of a scratch value overrode the original
push location.
<rdar://problem/19171178>
llvm-svn: 225431
Most of the changes are to the FuncUnwinders class -- as we've added
more types of unwind information, the way this class was written was
making it a mess to maintain. Instead of trying to keep one
"non-call site" unwind plan and one "call site" unwind plan, track
all the different types of unwind plans we can possibly retrieve for
each function and have the call-site/non-call-site accessor methods
retrieve those.
Add a real "fast unwind plan" for x86_64 / i386 -- when doing an
unwind through a function, this only has to read the first 4 bytes
to tell if the function has a standard prologue sequence. If so,
we can use the architecture default unwind plan to backtrace
through this function. If we try to retrieve the save location for
other registers later on, a real unwind plan will be used. This
one is just for doing fast backtraces.
Change the compact unwind plan importer to fill in the valid address
range it is valid for.
Compact unwind, in theory, may have multiple entries for a single
function. The FuncUnwinders rewrite includes the start of supporting
this correctly. In practice compact unwind encodings are used for
the entire range of the function today -- in fact, sometimes the same
encoding is used for multiple functions that have the same unwind
rules. But I want to handle a single function that has multiple
different compact unwind UnwindPlans eventually.
llvm-svn: 224689
section for x86_64 and i386 targets on Darwin systems. Currently only the
compact unwind encoding for normal frame-using functions is supported but it
will be easy handle frameless functions when I have a bit more free time to
test it. The LSDA and personality routines for functions are also retrieved
correctly for functions from the compact unwind section.
This new code is very fresh -- it passes the lldb testsuite and I've done
by-hand inspection of many functions and am getting correct behavior for all
of them. There may need to be some bug fixing over the next couple weeks as
I exercise and test it further. But I think it's fine right now so I'm
committing it.
<rdar://problem/13220837>
llvm-svn: 223625
MSVC warns that not all control paths return a value when a switch
doesn't have a default case handler. Changed explicit value checks
to a default check.
Also, it caught a case where bitwise AND was being used instead of
logical AND. I'm not sure what this fixes, but presumably it is
not covered by any kind of test case.
llvm-svn: 221636
a nop). Fixes an instruction stepping problem when trying to step
over the final instructions of an epilogue.
<rdar://problem/18068877>
llvm-svn: 221241
I wrote this originally as a part of an unwind library that was using
a different coding convention and some of that old style remained after
its integration into lldb.
llvm-svn: 216419
We decided to use assmbly profiler instead of eh_frame for frame 0 because for compiler generated code, eh_frame is usually synchronous(a.k.a. only valid at call site); and we have no way to tell if it's asynchronous or not.
But for x86 & x86_64 compiler generated code:
1. clang & GCC describes all prologue instructions in eh_frame;
2. mid-function stack pointer altering instructions can be easily detected.
So we can grab eh_frame, and use assembly profiler to augment it into asynchronous unwind table.
This change also benefits hand-written assembly; eh_frame for hand-written assembly is often asynchronous,so we have a much better chance to successfully unwind through them.
Change by Tong Shen.
llvm-svn: 216406
to recognize an epilogue that ends with a jmp to
objc_retainAutoreleaseReturnValue instead of a ret instruction.
<rdar://problem/17889928>
llvm-svn: 214783
This change has the practical effect of fixing some backtrace
scenarios that would fail with inferiors running on the Android Art
host-side JVM under Linux x86_64 on Ubuntu 14.04.
See this lldb-commits thread for more details:
http://lists.cs.uiuc.edu/pipermail/lldb-commits/Week-of-Mon-20140721/011988.html
Change by Tong Shen.
Reviewed by Jason Molenda.
Tested:
Ubuntu 14.04 x86_64, clang-3.5-built lldb.
MacOSX 10.10 Preview 4, Xcode 6 Beta 4-built lldb.
llvm-svn: 213914
This is a mechanical change addressing the various sign comparison warnings that
are identified by both clang and gcc. This helps cleanup some of the warning
spew that occurs during builds.
llvm-svn: 205390
the CFA instructions when it was profiling an -fomit-frame-pointer function
and a "volatile" register was saved on the stack (e.g. an argument register).
<rdar://problem/15036546>
llvm-svn: 191267
<rdar://problem/13594769>
Main changes in this patch include:
- cleanup plug-in interface and use ConstStrings for plug-in names
- Modfiied the BSD Archive plug-in to be able to pick out the correct .o file when .a files contain multiple .o files with the same name by using the timestamp
- Modified SymbolFileDWARFDebugMap to properly verify the timestamp on .o files it loads to ensure we don't load updated .o files and cause problems when debugging
The plug-in interface changes:
Modified the lldb_private::PluginInterface class that all plug-ins inherit from:
Changed:
virtual const char * GetPluginName() = 0;
To:
virtual ConstString GetPluginName() = 0;
Removed:
virtual const char * GetShortPluginName() = 0;
- Fixed up all plug-in to adhere to the new interface and to return lldb_private::ConstString values for the plug-in names.
- Fixed all plug-ins to return simple names with no prefixes. Some plug-ins had prefixes and most ones didn't, so now they all don't have prefixed names, just simple names like "linux", "gdb-remote", etc.
llvm-svn: 181631
- generate-vers.pl has to be called by cmake to generate the version number
- parallel builds not yet supported; dependency on clang must be explicitly specified
Tested on Linux.
- Building on Mac will require code-signing logic to be implemented.
- Building on Windows will require OS-detection logic and some selective directory inclusion
Thanks to Carlo Kok (who originally prepared these CMakefiles for Windows) and Ben Langmuir
who ported them to Linux!
llvm-svn: 175795
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
Pavel Labath