Commit Graph

60 Commits

Author SHA1 Message Date
Jason Molenda e589e7e336 The lldb unwinder can now use the unwind information from the compact-unwind
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
2014-12-08 03:09:00 +00:00
Zachary Turner ba80da60c8 Fix some compiler warnings, one of which was a legit bug.
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
2014-11-10 22:31:51 +00:00
Jason Molenda 8030ffda91 Add recognition for another x86 epilogue sequence (ret followed by
a nop).  Fixes an instruction stepping problem when trying to step
over the final instructions of an epilogue.
<rdar://problem/18068877> 

llvm-svn: 221241
2014-11-04 05:48:11 +00:00
Jason Molenda aff1b357b0 Add a new disassembly-format specification so that the disassembler
output style can be customized.  Change the built-in default to be
more similar to gdb's disassembly formatting.

The disassembly-format for a gdb-like output is

${addr-file-or-load} <${function.name-without-args}${function.concrete-only-addr-offset-no-padding}>: 

The disassembly-format for the lldb style output is

{${function.initial-function}{${module.file.basename}`}{${function.name-without-args}}:\n}{${function.changed}\n{${module.file.basename}`}{${function.name-without-args}}:\n}{${current-pc-arrow} }{${addr-file-or-load}}: 

The two backticks in the lldb style formatter triggers the sub-expression evaluation in
CommandInterpreter::PreprocessCommand() so you can't use that one as-is ... changing to
use ' characters instead of ` would work around that.

<rdar://problem/9885398> 

llvm-svn: 219544
2014-10-10 23:07:36 +00:00
Jason Molenda 7b967f1477 Remove trailing whitespace from lines in UnwindAssembly-x86.cpp. No other changes.
llvm-svn: 216420
2014-08-25 23:46:06 +00:00
Jason Molenda 31e7191513 Clean up the coding conventions in UnwindAssembly-x86.cpp a little bit.
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
2014-08-25 23:45:24 +00:00
Jason Molenda 1786ebf3d4 Have augment_unwind_plan_from_call_site update the UnwindPlan
name/from-compiler settings to indicate that it was augmented
by assembly profiling.

llvm-svn: 216412
2014-08-25 22:16:23 +00:00
Todd Fiala 0562524b45 On x86 & x86_64, try to use eh_frame for frame 0.
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
2014-08-25 20:29:09 +00:00
Jason Molenda 300dfcd28d Add code to AssemblyParse_x86::get_non_call_site_unwind_plan
to recognize an epilogue that ends with a jmp to 
objc_retainAutoreleaseReturnValue instead of a ret instruction.
<rdar://problem/17889928> 

llvm-svn: 214783
2014-08-04 21:26:55 +00:00
Todd Fiala d947406427 Fix an x86 assembler stack unwind calculation for non-volatile registers.
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
2014-07-25 01:15:34 +00:00
Jean-Daniel Dupas e7c7c3de93 Replace uint32_t by lldb::RegisterKing in register context API.
llvm-svn: 212172
2014-07-02 09:51:28 +00:00
Bruce Mitchener d93c4a3339 Fix typos.
llvm-svn: 212132
2014-07-01 21:22:11 +00:00
Saleem Abdulrasool 3985c8c646 sanitise sign comparisons
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
2014-04-02 03:51:35 +00:00
Joerg Sonnenberger 340a17595e Convert to UNIX line endings.
llvm-svn: 191367
2013-09-25 10:37:32 +00:00
Jason Molenda 378a462c1a Fix a bug where the x86 assembly instruction profiler would not correctly adjust
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
2013-09-24 03:28:54 +00:00
Jason Molenda 6b3e6d5487 Disassembler::DisassembleRange() currently calls Target::ReadMemory
with prefer_file_cache == false.  This is what we want to do when
the user is doing a disassemble command -- show the actual memory
contents in case the memory has been corrupted or something -- but
when we're profiling functions for stepping or unwinding
(ThreadPlanStepRange::GetInstructionsForAddress,
UnwindAssemblyInstEmulation::GetNonCallSiteUnwindP) we can read
__TEXT instructions directly out of the file, if it exists.
<rdar://problem/14397491> 

llvm-svn: 190638
2013-09-12 23:23:35 +00:00
Jim Ingham 56d404281f The DisassemblerLLVMC has a retain cycle - the InstructionLLVMC's contained in its instruction
list have a shared pointer back to their DisassemblerLLVMC.  This checkin force clears the InstructionList
in all the places we use the DisassemblerSP to stop the leaking for now.  I'll go back and fix this
for real when I have time to do so.

<rdar://problem/14581918>

llvm-svn: 187473
2013-07-31 02:19:15 +00:00
Greg Clayton 57abc5d6a6 <rdar://problem/13854277>
<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
2013-05-10 21:47:16 +00:00
Greg Clayton 7b0992d9cd After discussing with Chris Lattner, we require C++11, so lets get rid of the macros and just use C++11.
llvm-svn: 179805
2013-04-18 22:45:39 +00:00
Greg Clayton e01e07b6e7 Since we use C++11, we should switch over to using std::unique_ptr when C++11 is being used. To do this, we follow what we have done for shared pointers and we define a STD_UNIQUE_PTR macro that can be used and it will "do the right thing". Due to some API differences in std::unique_ptr and due to the fact that we need to be able to compile without C++11, we can't use move semantics so some code needed to change so that it can compile with either C++.
Anyone wanting to use a unique_ptr or auto_ptr should now use the "STD_UNIQUE_PTR(TYPE)" macro.

llvm-svn: 179779
2013-04-18 18:10:51 +00:00
Greg Clayton 5160ce5c72 <rdar://problem/13521159>
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
2013-03-27 23:08:40 +00:00
Jim Ingham 0f063ba6b4 Convert from the C-based LLVM Disassembler shim to the full MC Disassembler API's.
Calculate "can branch" using the MC API's rather than our hand-rolled regex'es.
As extra credit, allow setting the disassembly flavor for x86 based architectures to intel or att.

<rdar://problem/11319574>
<rdar://problem/9329275>

llvm-svn: 176392
2013-03-02 00:26:47 +00:00
Daniel Malea 23720cc66c Adding CMake build system to LLDB. Some known issues remain:
- 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
2013-02-21 20:58:22 +00:00
Sean Callanan 5deaa4c902 Made LLDB compile with LLVM top-of-tree again.
The results from Clang name lookups changed to
be ArrayRefs, so I had to change the way we
check for the presence of a result and the way
we iterate across results.

llvm-svn: 170927
2012-12-21 21:34:42 +00:00
Daniel Malea 89660bf795 More Linux warnings fixes (remove default labels as needed):
- as per http://llvm.org/docs/CodingStandards.html#don-t-use-default-labels-in-fully-covered-switches-over-enumerations

Patch by Matt Kopec!

llvm-svn: 169633
2012-12-07 20:51:09 +00:00
Daniel Malea d01b2953fa Resolve printf formatting warnings on Linux:
- use macros from inttypes.h for format strings instead of OS-specific types

Patch from Matt Kopec!

llvm-svn: 168945
2012-11-29 21:49:15 +00:00
Jason Molenda 60f0bd4944 Add a new capability to RegisterContextLLDB: To recognize when the
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
2012-10-26 06:08:58 +00:00
Jason Molenda 7cd5e831e5 Change how the UnwindAssemblyInstEmulation class tracks the setup of
the function's prologue instructions so we can re-instate that prologue
if we hit an early return mid-function.  Add some additional heuristics
to differentiate between prologue and epilogue instruction sequences.

This fixes the specific problem of correctly unwinding through a function
which has an epilogue one instruction after the last prologue setup
instruction has completed.
<rdar://problem/12091139> 

llvm-svn: 166465
2012-10-23 03:08:31 +00:00
Jason Molenda 5c1ac4ea72 Add code to UnwindAssemblyInstEmulation::GetNonCallSiteUnwindPlanFromAssembly
to handle an addition class of early-return instructions we find in arm code:
tail-call optimziation returns where we restore the register state from the
function entry and jump directly (not branch & link) to another function --
when that other function returns, it will return to our caller.

Previously this mid-function epilogue sequence was not being correctly detected.
We would not re-instate the prologue setup instructions for the rest of the function
so unwinds would break from that point until the end of the function.
<rdar://problem/12502597> 

llvm-svn: 166081
2012-10-17 00:41:14 +00:00
Jason Molenda 22f2fff3ff Change the scratch buffer for x86 assembly instructions in AssemblyParse_x86 from
malloc'ed heap to an llvm SmallVector.

llvm-svn: 165703
2012-10-11 06:04:37 +00:00
Jason Molenda 64dc7798a4 Move the scratch buffer allocation for x86 instructions from being allocated each instruction,
to once in the AssemblyParse_x86 ctor.
an instruction

llvm-svn: 165662
2012-10-10 21:37:00 +00:00
Jason Molenda a72778119e Free the opcode_data malloc'ed memory instead of leaking it - thanks for catching that, Chris.
llvm-svn: 165597
2012-10-10 03:47:23 +00:00
Jason Molenda a8399a8cf1 Change the x86 unwinder from using edis as its disassembler
API (to get the length of x86 instructions) to using the LLVM-MC
disassembler.
<rdar://problem/12411000>

llvm-svn: 165587
2012-10-10 01:45:33 +00:00
Greg Clayton 43e0af06b4 Stop using the "%z" size_t modifier and cast all size_t values to uint64_t. Some platforms don't support this modification.
llvm-svn: 164148
2012-09-18 18:04:04 +00:00
Greg Clayton 1f7460716b <rdar://problem/11757916>
Make breakpoint setting by file and line much more efficient by only looking for inlined breakpoint locations if we are setting a breakpoint in anything but a source implementation file. Implementing this complex for a many reasons. Turns out that parsing compile units lazily had some issues with respect to how we need to do things with DWARF in .o files. So the fixes in the checkin for this makes these changes:
- Add a new setting called "target.inline-breakpoint-strategy" which can be set to "never", "always", or "headers". "never" will never try and set any inlined breakpoints (fastest). "always" always looks for inlined breakpoint locations (slowest, but most accurate). "headers", which is the default setting, will only look for inlined breakpoint locations if the breakpoint is set in what are consudered to be header files, which is realy defined as "not in an implementation source file". 
- modify the breakpoint setting by file and line to check the current "target.inline-breakpoint-strategy" setting and act accordingly
- Modify compile units to be able to get their language and other info lazily. This allows us to create compile units from the debug map and not have to fill all of the details in, and then lazily discover this information as we go on debuggging. This is needed to avoid parsing all .o files when setting breakpoints in implementation only files (no inlines). Otherwise we would need to parse the .o file, the object file (mach-o in our case) and the symbol file (DWARF in the object file) just to see what the compile unit was.
- modify the "SymbolFileDWARFDebugMap" to subclass lldb_private::Module so that the virtual "GetObjectFile()" and "GetSymbolVendor()" functions can be intercepted when the .o file contenst are later lazilly needed. Prior to this fix, when we first instantiated the "SymbolFileDWARFDebugMap" class, we would also make modules, object files and symbol files for every .o file in the debug map because we needed to fix up the sections in the .o files with information that is in the executable debug map. Now we lazily do this in the DebugMapModule::GetObjectFile()

Cleaned up header includes a bit as well.

llvm-svn: 162860
2012-08-29 21:13:06 +00:00
Jason Molenda 4d04d477d9 When emulating instructions that read from memory,
return 0x0 as the read value instead of uninitialized
stack data so we get consistent behavior from the
emulator.
<rdar://problem/12058770>

llvm-svn: 161795
2012-08-13 21:53:35 +00:00
Jason Molenda 24a8378c4f Change UnwindAssemblyInstEmulation::GetNonCallSiteUnwindPlanFromAssembly so it records
the state of the unwind instructions once the prologue has finished.  If it hits an
early return epilogue in the middle of the function, re-instate the prologue after that
epilogue has completed so that we can still unwind for cases where the flow of control
goes past that early-return.  <rdar://problem/11775059>

Move the UnwindPlan operator== definition into the .cpp file, expand the definition a bit.

Add some casts to a SBCommandInterpreter::HandleCompletion() log statement so it builds without
warning on 64- and 32-bit systems.

llvm-svn: 160337
2012-07-17 01:57:24 +00:00
Jason Molenda 1d42c7bc32 Switch nearly all of the use of the UnwindPlan::Row's to go through
a shared pointer to ease some memory management issues with a patch
I'm working on.

The main complication with using SPs for these objects is that most
methods that build up an UnwindPlan will construct a Row to a given
instruction point in a function, then add additional regsaves in
the next instruction point to that row and push it again.  A little
care is needed to not mutate the previous instruction point's Row
once these are switched to being held behing shared pointers.

llvm-svn: 160214
2012-07-14 04:52:53 +00:00
Jason Molenda 7298ea1871 Revert the change I committed yesterday, it caused a regression
with one armv7 unwind.  I'll look at updating this or finding a
different way of fixing it later tonight.

llvm-svn: 160198
2012-07-13 22:40:51 +00:00
Jason Molenda d59fd74eec When parsing the epilogue of a thumbv2 function, when we see the
frame pointer overwritten with the caller's fp value, return to 
expressing the CFA in terms of the stack pointer.
<rdar://problem/11855862>

llvm-svn: 160150
2012-07-12 23:43:02 +00:00
Jason Molenda 75b9cfd1f0 Simplify the CreateDefaultUnwindPlan methods for the x86 and arm unwinders
a bit -- we're creating the UnwindPlan here, we can set the register set to
whatever is convenient for us, no need to handle different register sets.

A handful of small comment fixes I noticed while reading through the code.

llvm-svn: 159924
2012-07-09 07:47:47 +00:00
Jason Molenda 6f5e8c2647 Add support for function with stack frame checks added by the compiler;
these functions will end in the sequence

  mov %rbp, %rsp
  ret
  call __stack_chk_fail

instead of the usual mov, ret.  The x86 assembly profiler only looked
for functions ending in 'ret' and added the Unwind row describing how to
set the CFA based on that -- the addition of the call insn (which is jumped
to earlier in the function body) threw off that inspection.

Resolves the need to "step" twice to get out of these functions when doing
source-level stepping.

<rdar://problem/11469705>

llvm-svn: 157454
2012-05-25 01:54:06 +00:00
Greg Clayton ba812f4284 <rdar://problem/11330621>
Fixed the DisassemblerLLVMC disassembler to parse more efficiently instead of parsing opcodes over and over. The InstructionLLVMC class now only reads the opcode in the InstructionLLVMC::Decode function. This can be done very efficiently for ARM and architectures that have fixed opcode sizes. For x64 it still calls the disassembler to get the byte size.

Moved the lldb_private::Instruction::Dump(...) function up into the lldb_private::Instruction class and it now uses the function that gets the mnemonic, operandes and comments so that all disassembly is using the same code.

Added StreamString::FillLastLineToColumn() to allow filling a line up to a column with a character (which is used by the lldb_private::Instruction::Dump(...) function).

Modified the Opcode::GetData() fucntion to "do the right thing" for thumb instructions.

llvm-svn: 156532
2012-05-10 02:52:23 +00:00
Greg Clayton 1ac04c3088 Thread hardening part 3. Now lldb_private::Thread objects have std::weak_ptr
objects for the backlink to the lldb_private::Process. The issues we were
running into before was someone was holding onto a shared pointer to a 
lldb_private::Thread for too long, and the lldb_private::Process parent object
would get destroyed and the lldb_private::Thread had a "Process &m_process"
member which would just treat whatever memory that used to be a Process as a
valid Process. This was mostly happening for lldb_private::StackFrame objects
that had a member like "Thread &m_thread". So this completes the internal
strong/weak changes.

Documented the ExecutionContext and ExecutionContextRef classes so that our
LLDB developers can understand when and where to use ExecutionContext and 
ExecutionContextRef objects.

llvm-svn: 151009
2012-02-21 00:09:25 +00:00
Johnny Chen 62212f0e62 Patch from Daniel Dunbar for future-proof against http://llvm.org/viewvc/llvm-project?view=rev&revision=145331.
llvm-svn: 145345
2011-11-29 01:09:49 +00:00
Jason Molenda 560183fd2d Fix verbose logging of unwinders.
llvm-svn: 140817
2011-09-29 22:34:41 +00:00
Greg Clayton c14ee32db5 Converted the lldb_private::Process over to use the intrusive
shared pointers.

Changed the ExecutionContext over to use shared pointers for
the target, process, thread and frame since these objects can
easily go away at any time and any object that was holding onto
an ExecutionContext was running the risk of using a bad object.

Now that the shared pointers for target, process, thread and
frame are just a single pointer (they all use the instrusive
shared pointers) the execution context is much safer and still
the same size. 

Made the shared pointers in the the ExecutionContext class protected
and made accessors for all of the various ways to get at the pointers,
references, and shared pointers.

llvm-svn: 140298
2011-09-22 04:58:26 +00:00
Jason Molenda 113f2d5289 Tighten up the 'log enable lldb unwind' printing for
the arm emulate instruction unwinder so you can leave it
on by default and not be overwhelmed.  Set verbose mode to
get the full story on how the unwindplans were created.

llvm-svn: 139897
2011-09-16 01:32:10 +00:00
Peter Collingbourne 5e494f4fe9 Add UnwindAssembly plugins to makefile build
llvm-svn: 131650
2011-05-19 17:34:58 +00:00
Greg Clayton 9a8fa9161f Added generic register numbers for simple ABI argument registers and defined
the appropriate registers for arm and x86_64. The register names for the
arguments that are the size of a pointer or less are all named "arg1", "arg2",
etc. This allows you to read these registers by name:

(lldb) register read arg1 arg2 arg3
...

You can also now specify you want to see alternate register names when executing
the read register command:

(lldb) register read --alternate
(lldb) register read -A

llvm-svn: 131376
2011-05-15 04:12:07 +00:00