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
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
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
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
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
are defined as enumerations. Current bits include:
eEmulateInstructionOptionAutoAdvancePC
eEmulateInstructionOptionIgnoreConditions
Modified the EmulateInstruction class to have a few more pure virtuals that
can help clients understand how many instructions the emulator can handle:
virtual bool
SupportsEmulatingIntructionsOfType (InstructionType inst_type) = 0;
Where instruction types are defined as:
//------------------------------------------------------------------
/// Instruction types
//------------------------------------------------------------------
typedef enum InstructionType
{
eInstructionTypeAny, // Support for any instructions at all (at least one)
eInstructionTypePrologueEpilogue, // All prologue and epilogue instructons that push and pop register values and modify sp/fp
eInstructionTypePCModifying, // Any instruction that modifies the program counter/instruction pointer
eInstructionTypeAll // All instructions of any kind
} InstructionType;
This allows use to tell what an emulator can do and also allows us to request
these abilities when we are finding the plug-in interface.
Added the ability for an EmulateInstruction class to get the register names
for any registers that are part of the emulation. This helps with being able
to dump and log effectively.
The UnwindAssembly class now stores the architecture it was created with in
case it is needed later in the unwinding process.
Added a function that can tell us DWARF register names for ARM that goes
along with the source/Utility/ARM_DWARF_Registers.h file:
source/Utility/ARM_DWARF_Registers.c
Took some of plug-ins out of the lldb_private namespace.
llvm-svn: 130189
Jason Molenda