Make sure we figure out correct plt entry field in case linker has generated a small value below realistic entry size like 4 bytes or below.
Differential revision: http://reviews.llvm.org/D19252
llvm-svn: 267405
RegisterContextLLDB::InitializeNonZerothFrame already has code to attempt
to detect and handle the case where the PC points beyond the end of a
function, but there are certain cases where this doesn't work correctly.
In fact, there are *two* different places where this detection is attempted,
and the failure is in fact a result of an unfortunate interaction between
those two separate attempts.
First, the ResolveSymbolContextForAddress routine is called with the
resolve_tail_call_address flag set to true. This causes the routine
to internally accept a PC pointing beyond the end of a function, and
still resolving the PC to that function symbol.
Second, the InitializeNonZerothFrame routine itself maintains a
"decr_pc_and_recompute_addr_range" flag and, if that turns out to
be true, itself decrements the PC by one and searches again for
a symbol at that new PC value.
Both approaches correctly identify the symbol associated with the PC.
However, the problem is now that later on, we also need to find the
DWARF CFI record associated with the PC. This is done in the
RegisterContextLLDB::GetFullUnwindPlanForFrame routine, and uses
the "m_current_offset_backed_up_one" member variable.
However, that variable only actually contains the PC "backed up by
one" if the *second* approach above was taken. If the function was
already identified via the first approach above, that member variable
is *not* backed up by one but simply points to the original PC.
This in turn causes GetEHFrameUnwindPlan to not correctly identify
the DWARF CFI record associated with the PC.
Now, in many cases, if the first method had to back up the PC by one,
we *still* use the second method too, because of this piece of code:
// Or if we're in the middle of the stack (and not "above" an asynchronous event like sigtramp),
// and our "current" pc is the start of a function...
if (m_sym_ctx_valid
&& GetNextFrame()->m_frame_type != eTrapHandlerFrame
&& GetNextFrame()->m_frame_type != eDebuggerFrame
&& addr_range.GetBaseAddress().IsValid()
&& addr_range.GetBaseAddress().GetSection() == m_current_pc.GetSection()
&& addr_range.GetBaseAddress().GetOffset() == m_current_pc.GetOffset())
{
decr_pc_and_recompute_addr_range = true;
}
In many cases, when the PC is one beyond the end of the current function,
it will indeed then be exactly at the start of the next function. But this
is not always the case, e.g. if there happens to be alignment padding
between the end of one function and the start of the next.
In those cases, we may sucessfully look up the function symbol via
ResolveSymbolContextForAddress, but *not* set decr_pc_and_recompute_addr_range,
and therefore fail to find the correct DWARF CFI record.
A very simple fix for this problem is to just never use the first method.
Call ResolveSymbolContextForAddress with resolve_tail_call_address set
to false, which will cause it to fail if the PC is beyond the end of
the current function; or else, identify the next function if the PC
is also at the start of the next function. In either case, we will
then set the decr_pc_and_recompute_addr_range variable and back up the
PC anyway, but this time also find the correct DWARF CFI.
A related problem is that the ResolveSymbolContextForAddress sometimes
returns a "symbol" with empty name. This turns out to be an ELF section
symbol. Now, usually those get type eSymbolTypeInvalid. However, there
is code in ObjectFileELF::ParseSymbols that tries to change the type of
invalid symbols to eSymbolTypeCode or eSymbolTypeData if the symbol
lies within the code or data section.
Unfortunately, this check also hits the symbol for the code section
itself, which is then marked as eSymbolTypeCode. While the size of
the section symbol is 0 according to the ELF file, LLDB considers
this size invalid and attempts to figure out the "correct" size.
Depending on how this goes, we may end up with a symbol that overlays
part of the code section, even outside areas covered by real function
symbols.
Therefore, if we call ResolveSymbolContextForAddress with PC pointing
beyond the end of a function, we may get this bogus section symbol.
This again means InitializeNonZerothFrame thinks we have a valid PC,
but then we don't find any unwind info for it.
The fix for this problem is me to simply always leave ELF section
symbols as type eSymbolTypeInvalid.
Differential Revision: http://reviews.llvm.org/D18975
llvm-svn: 267363
This adds basic parsing of the EABI attributes section. This section contains
additional information about the target for which the file was built. Attempt
to infer additional architecture information from that section.
llvm-svn: 267291
Code in ObjectFileELF::ParseTrampolineSymbols assumes that the sh_info
field of the .rel(a).plt section identifies the .plt section.
However, with recent GNU ld this is no longer true. As a result of this:
https://sourceware.org/bugzilla/show_bug.cgi?id=18169
in object files generated with current linkers the sh_info field of
.rel(a).plt now points to the .got.plt section (or .got on some targets).
This causes LLDB to fail to identify any PLT stubs, causing a number of
test case failures.
This patch changes LLDB to simply always look for the .plt section by
name. This should be safe across all linkers and targets.
Differential Revision: http://reviews.llvm.org/D18973
llvm-svn: 266316
Build-id support is being added to lld and by default it may produce a
64-bit build-id.
Prior to this change lldb would reject such a build-id. However, it then
falls back to a 4-byte crc32, which is a poorer quality identifier.
Differential Revision: http://reviews.llvm.org/D18096
llvm-svn: 263432
Most address represented in lldb as section plus offset and handling of
absolute addresses is problematic in several location because of lack
of necessary information (e.g. Target) or because of performance issues.
This CL change the way ObjectFileELF handle the absolute symbols with
creating a pseudo section for each symbol. With this change all existing
code designed to work with addresses in the form of section plus offset
will work with absolute symbols as well.
Differential revision: http://reviews.llvm.org/D17450
llvm-svn: 261859
* 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
This patch adds logic to detect if underlying binary is using arm hard float abi and use that information while handling return values in ABISysV_arm.
Differential revision: http://reviews.llvm.org/D16627
llvm-svn: 259885
Summary:
The issue arises because LLDB is not
able to read the vdso library correctly.
The fix adds memory allocation callbacks
to allocate sufficient memory in case the
requested offsets don't fit in the memory
buffer allocated for the ELF.
Reviewers: lldb-commits, clayborg, deepak2427, ovyalov, labath, tberghammer
Differential Revision: http://reviews.llvm.org/D16107
llvm-svn: 258122
The ELF symbol table always contain the size of the symbols so we
don't have to try to guess them based on the address of the next
symbol (it is needed for mach-o).
The change fixes an issue when a symbol is removed after a 0 size
symbol (e.g. because the second one is not public) what previously
caused the symbol lookup algorithm to end up with showing the 0 size
symbol even for the later addresses (what are not part of any symbol).
That symbol lookup error can confuse the user and also confuses the
current stack unwinder.
Re-commit this CL after fixing the issue with gcc-4.9.2 on i386 Linux.
Differential revision: http://reviews.llvm.org/D16186
llvm-svn: 258113
The ELF symbol table always contain the size of the symbols so we
don't have to try to guess them based on the address of the next
symbol (it is needed for mach-o).
The change fixes an issue when a symbol is removed after a 0 size
symbol (e.g. because the second one is not public) what previously
caused the symbol lookup algorithm to end up with showing the 0 size
symbol even for the later addresses (what are not part of any symbol).
That symbol lookup error can confuse the user and also confuses the
current stack unwinder.
Differential revision: http://reviews.llvm.org/D16186
llvm-svn: 258040
Summary:
This was used with the old ARM vs. Thumb detection code but is not
required anymore.
Reviewers: tberghammer, clayborg
Subscribers: fjricci, aemerson, lldb-commits, rengolin
Differential Revision: http://reviews.llvm.org/D16099
llvm-svn: 257429
(There are changes in the copies of these four files in the FreeBSD base
system, and I've changed these ones to reduce gratuitous diffs in future
imports.)
llvm-svn: 256723
Summary:
DWARF 5 proposes a reinvented .debug_macro section. This change follows
that spec.
Currently, only GCC produces the .debug_macro section and hence
the added test is annottated with expectedFailureClang.
Reviewers: spyffe, clayborg, tberghammer
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D15437
llvm-svn: 255729
To do this I added a few new ways to determine the OS from PT_NOTE notes in the ELF file:
1 - Look for "LINUX" notes which indicate "linux" should be the OS
2 - Look through the "CORE" notes with NT_FILE as the type and sniff data from the paths listed in this section. On Ubuntu they contain "/lib/x86_64-linux-gnu" which has the triple and allows us to set "linux" as the OS in the architecture returned from ObjectFileELF::GetArchitecture().
Setting the OS correctly allows us to get the triple correct so we can extract registers without asserting and killing LLDB.
Also use the data from the NT_FILE to set the main executable if one isn't set in ProcessElfCore::DoLoadCore().
llvm-svn: 251537
* Remove an unneccessary re-computaion on arch spec from the ELF file
* Use a local cache to optimize name based section lookups in symtab
parsing
* Optimize C++ method basename validation with replacing a regex with
hand written code
These modifications reduce the time required to parse the symtab from
large applications by ~25% (tested with LLDB as inferior)
Differential revision: http://reviews.llvm.org/D14088
llvm-svn: 251402
* ArchSpec::MergeFrom() would erroneously promote an unspecified
unknown to a specified unknown when both the ArchSpec and the merged
in ArchSpec were both unspecified unknowns. This no longer happens,
which fixes issues with global module cache lookup in some
situations.
* Added ArchSpec::DumpTriple(Stream&) that now properly prints
unspecified unknowns as '*' and specified unknows as 'unknown'.
This makes it trivial to tell the difference between the two.
Converted printing code over ot using DumpTriple() rather than
building from scratch.
* Fixed up a couple places that were not guaranteeing that an
unspecified unknown was recorded as such.
llvm-svn: 250253
GP registers for o32 applications were always giving zero value because SetType() on the RegisterValue was causing the accessor functions to pickup the value from m_scalar of RegisterValue which is zero.
In this patch byte size and byte order of register value is set at the time of setting the value of the register.
llvm-svn: 249020
.ARM.exidx/.ARM.extab sections contain unwind information used on ARM
architecture from unwinding from an exception.
Differential revision: http://reviews.llvm.org/D13245
llvm-svn: 248903
The Go runtime schedules user level threads (goroutines) across real threads.
This adds an OS plugin to create memory threads for goroutines.
It supports the 1.4 and 1.5 go runtime.
Differential Revision: http://reviews.llvm.org/D5871
llvm-svn: 247852
SUMMARY:
This patch provides support for MIPS specific DT_MIPS_RLD_MAP_REL tag in LLDB.
This tag allows debugging of MIPS position independent executables and provides access to shared library information.
Reviewers: clayborg
Subscribers: mohit.bhakkad, sagar, jaydeep, lldb-commits
Differential Revision: http://reviews.llvm.org/D12794
llvm-svn: 247666
Change the mapping symbol handling to handle the case when the mapping
symbols are prefixed with an arbitrary prefix. This isn't strictly standard
compliance, but if all symbols in an object file is prefixed with objcopy
then the prefix will be added to the mapping symbol also. We still want to
treat these symbols as mapping symbols to get the correct address class data.
Differential revision: http://reviews.llvm.org/D12755
llvm-svn: 247400
* Create new dwo symbol file class
* Add handling for .dwo sections
* Change indexes in SymbolFileDWARF to store compile unit offset next to
DIE offset
* Propagate queries from dwarf compile unit to the dwo compile unit
where applicable
Differential revision: http://reviews.llvm.org/D12291
llvm-svn: 247132
These are 2 new value currently in experimental status used when split
debug info is enabled.
Differential revision: http://reviews.llvm.org/D12238
llvm-svn: 245931
The POSIX linker generally reports the load bias for the loaded
libraries but in some case it is useful to handle a library based on
absolute load address. Example usecases:
* Windows linker uses absolute addresses
* Library list came from different source (e.g. /proc/<pid>/maps)
Differential revision: http://reviews.llvm.org/D12233
llvm-svn: 245834
SUMMARY:
The patch detects MIPS application specific extensions (ASE) like micromips by reading
ELF header.e_flags and SHT_MIPS_ABIFLAGS section. MIPS triple does not contain ASE
information like micromips, mips16, DSP, MSA etc. These can be read from header.e_flags
or SHT_MIPS_ABIFLAGS section.
Reviewers: clayborg
Subscribers: mohit.bhakkad, sagar, lldb-commits
Differential Revision: http://reviews.llvm.org/D11133
llvm-svn: 242381
On Android the oatdata and the oatexec symbols in
system@framework@boot.oat covers the full .text section what causes
issues with displaying unusable symbol name to the user and very slow
unwinding speed because the instruction emulation based unwind plans
try to emulate all instructions in these symbols. Don't add these
symbols to the symbol list as they have no use for the debugger and
they are causing a lot of trouble.
Differential revision: http://reviews.llvm.org/D11065
llvm-svn: 242017
Summary: Use string::find(char) for single character strings.
Reviewers: abidh, ki.stfu, clayborg
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D10943
llvm-svn: 241390
* Add in-memory object file handling to the core dynamic loader
* Fix in memory object file handling in ObjectFileELF (previously
only part of the file was loaded before parsing)
* Fix load address setting in ObjectFileELF for 32-bit targets
when the load bias is negative
* Change hack in DYLDRendezvous.cpp to be more specific and not to
interfere with object files with fixed load address
Differential revision: http://reviews.llvm.org/D10800
llvm-svn: 241057
A few extras were fixed
- Symbol::GetAddress() now returns an Address object, not a reference. There were places where people were accessing the address of a symbol when the symbol's value wasn't an address symbol. On MacOSX, undefined symbols have a value zero and some places where using the symbol's address and getting an absolute address of zero (since an Address object with no section and an m_offset whose value isn't LLDB_INVALID_ADDRESS is considered an absolute address). So fixing this required some changes to make sure people were getting what they expected.
- Since some places want to access the address as a reference, I added a few new functions to symbol:
Address &Symbol::GetAddressRef();
const Address &Symbol::GetAddressRef() const;
Linux test suite passes just fine now.
<rdar://problem/21494354>
llvm-svn: 240702
* Add and fix the emulation of several instruction.
* Disable frame pointer usage on Android.
* Specify return address register for the unwind plan instead of explict
tracking the value of RA.
* Replace prologue detection heuristics (unreliable in several cases)
with a logic to follow the branch instructions and restore the CFI
value based on them. The target address for a branch should have the
same CFI as the source address (if they are in the same function).
* Handle symbols in ELF files where the symbol size is not specified
with calcualting their size based on the next symbol (already done
in MachO files).
* Fix architecture in FuncUnwinders with filling up the inforamtion
missing from the object file with the architecture of the target.
* Add code to read register wehn the value is set to "IsSame" as it
meanse the value of a register in the parent frame is the same as the
value in the current frame.
Differential revision: http://reviews.llvm.org/D10447
llvm-svn: 240533
Setting the OSType in the ArchSpec triple is needed to correctly setup
up the register context plugin. ArchSpec::SetArchitecture, for Mach-O
only, sets the OSType. For ELF it was left to the ObjectFileELF to fill
in the missing OSType.
This change moves the ObjectFileELF logic into ArchSpec.
A new optional 'os' parameter has been added to SetArchitecture.
For ELF, this value is the from the ELF header.e_ident[EI_OSABI].
The default value is 0 or ELFOSABI_NONE.
The real work of determining the OSType was done by the ObjectFileELF
helper function GetOsFromOSABI. This logic has been moved
SetArchitecture.
GetOsFromOSABI has been commented as being deprectated. It is left in
to support asserts.
For ELF the vendor value returned from SetArchitecture should be
UnknownVendor. An unneeded resetting in ObjectFileELF has been removed
and replaced with an assert.
This fixes a problem reading a core file on FreeBSD/ARM because the spec
triple was arm-unknown-unknown.
Patch by Tom Rix.
Differential Revision: http://reviews.llvm.org/D9292
llvm-svn: 239148
The ELF data contains two different errors in some ELF files on android.
* The link field of the symbol table don't point to the plt section or
to the dynsym section even when it is present in the ELF files.
* The size of the plt entries aren't specified in the section header of
the plt section.
This CL adds some workarounds for these two issue with finding the
sections by name if the link field is empty and by using a heuristic to
calculate the size and offset of the plt entries.
Differential revision: http://reviews.llvm.org/D9560
llvm-svn: 236818
