in the test suite. While this is not really an interesting tool and option to run
on a Mach-O file to show the symbol table in a generic libObject format
it shouldn’t crash.
The reason for the crash was in MachOObjectFile::getSymbolType() when it was
calling MachOObjectFile::getSymbolSection() without checking its return value
for the error case.
What makes this fix require a fair bit of diffs is that the method getSymbolType() is
in the class ObjectFile defined without an ErrorOr<> so I needed to add that all
the sub classes. And all of the uses needed to be updated and the return value
needed to be checked for the error case.
The MachOObjectFile version of getSymbolType() “can” get an error in trying to
come up with the libObject’s internal SymbolRef::Type when the Mach-O symbol
symbol type is an N_SECT type because the code is trying to select from the
SymbolRef::ST_Data or SymbolRef::ST_Function values for the SymbolRef::Type.
And it needs the Mach-O section to use isData() and isBSS to determine if
it will return SymbolRef::ST_Data.
One other possible fix I considered is to simply return SymbolRef::ST_Other
when MachOObjectFile::getSymbolSection() returned an error. But since in
the past when I did such changes that “ate an error in the libObject code” I
was asked instead to push the error out of the libObject code I chose not
to implement the fix this way.
As currently written both the COFF and ELF versions of getSymbolType()
can’t get an error. But if isReservedSectionNumber() wanted to check for
the two known negative values rather than allowing all negative values or
the code wanted to add the same check as in getSymbolAddress() to use
getSection() and check for the error then these versions of getSymbolType()
could return errors.
At the end of the day the error printed now is the generic “Invalid data was
encountered while parsing the file” for object_error::parse_failed. In the
future when we thread Lang’s new TypedError for recoverable error handling
though libObject this will improve. And where the added // Diagnostic(…
comment is, it would be changed to produce and error message
like “bad section index (42) for symbol at index 8” for this case.
llvm-svn: 264187
In executable and shared object ELF files, relocations in the file contain the final virtual address rather than section offset so this is adjusted to display section offset.
Differential revision: http://reviews.llvm.org/D15965
llvm-svn: 263971
The section alignment field was marked optional but not provided a
default value: initialize it with 0.
While we are here, ensure that the section alignment is plausible.
llvm-svn: 263692
The dynamic table is also an array of a fixed structure, so it can be
represented with a DynReginoInfo.
No major functionality change. The extra error checking is covered by
existing tests with a broken dynamic program header.
Idea extracted from r260488. I did the extra cleanups.
llvm-svn: 261107
We used to keep both a section and a pointer to the first symbol.
The oddity of keeping a section for dynamic symbols is because there is
a DT_SYMTAB but no DT_SYMTABZ, so to print the table we have to find the
size via a section table.
The reason for still keeping a pointer to the first symbol is because we
want to be able to print relocation tables even if the section table is
missing (it is mandatory only for files used in linking).
With this patch we keep just a DynRegionInfo. This then requires
changing a few places that were asking for a Elf_Shdr but actually just
needed the first symbol.
The test change is to delete the program header pointer.
Now that we use the information of both DT_SYMTAB and .dynsym, we don't
depend on the sh_entsize of .dynsym if we see DT_SYMTAB.
Note: It is questionable if it is worth it putting the effort to report
broken sh_entsize given that in files with no section table we have to
assume it is sizeof(Elf_Sym), but that is for another change.
Extracted from r260488.
llvm-svn: 261099
Original commit message:
[readobj] Dump DT_JMPREL relocations when outputting dynamic relocations.
The bits of r260488 it depends on have been committed.
llvm-svn: 260970
This requires making an error message a bit more generic, but that seems
a reasonable tradeoff.
Extracted from r260488 but simplified a bit.
llvm-svn: 260967
Original messages:
Revert "[readobj] Handle ELF files with no section table or with no program headers."
Revert "[readobj] Dump DT_JMPREL relocations when outputting dynamic relocations."
r260489 depends on r260488 and among other issues r260488 deleted error
handling code.
llvm-svn: 260962
This adds support for finding the dynamic table and dynamic symbol table via
the section table or the program header table. If there's no section table an
attempt is made to figure out the length of the dynamic symbol table.
llvm-svn: 260488
at least as big as the mach header to be identified as a Mach-O file and
make sure smaller files are not identified as a Mach-O files but as
unknown files. Also fix identify_magic() so it looks at all 4 bytes of
the filetype field when determining the type of the Mach-O file.
Then fix the macho-invalid-header test case to check that it is an
unknown file and make sure it does not get the error for
object_error::parse_failed. And also update the unit tests.
llvm-svn: 258883
llvm-objdump when printing the Mach Header to print the unknown
cputype and cpusubtype fields as decimal instead of not printing
them at all. And change the test to check for that.
llvm-svn: 258826
in MachOObjectFile::getSymbolByIndex() when a Mach-O file has
a symbol table load command but the number of symbols are zero.
The code in MachOObjectFile::symbol_begin_impl() should not be
assuming there is a symbol at index 0, in cases there is no symbol
table load command or the count of symbol is zero. So I also fixed
that. And needed to fix MachOObjectFile::symbol_end_impl() to
also do the same thing for no symbol table or one with zero entries.
The code in MachOObjectFile::getSymbolByIndex() should trigger
the report_fatal_error() for programmatic errors for any index when
there is no symbol table load command and not return the end iterator.
So also fixed that. Note there is no test case as this is a programmatic
error.
The test case using the file macho-invalid-bad-symbol-index has
a symbol table load command with its number of symbols (nsyms)
is zero. Which was incorrectly testing the bad triggering of the
report_fatal_error() in in MachOObjectFile::getSymbolByIndex().
This test case is an invalid Mach-O file but not for that reason.
It appears this Mach-O file use to have an nsyms value of 11,
and what makes this Mach-O file invalid is the counts and
indexes into the symbol table of the dynamic load command
are now invalid because the number of symbol table entries
(nsyms) is now zero. Which can be seen with the existing
llvm-obdump:
% llvm-objdump -private-headers macho-invalid-bad-symbol-index
…
Load command 4
cmd LC_SYMTAB
cmdsize 24
symoff 4216
nsyms 0
stroff 4392
strsize 144
Load command 5
cmd LC_DYSYMTAB
cmdsize 80
ilocalsym 0
nlocalsym 8 (past the end of the symbol table)
iextdefsym 8 (greater than the number of symbols)
nextdefsym 2 (past the end of the symbol table)
iundefsym 10 (greater than the number of symbols)
nundefsym 1 (past the end of the symbol table)
...
And the native darwin tools generates an error for this file:
% nm macho-invalid-bad-symbol-index
nm: object: macho-invalid-bad-symbol-index truncated or malformed object (ilocalsym plus nlocalsym in LC_DYSYMTAB load command extends past the end of the symbol table)
I added new checks for the indexes and sizes for these in the
constructor of MachOObjectFile. And added comments for what
would be a proper diagnostic messages.
And changed the test case using macho-invalid-bad-symbol-index
to test for the new error now produced.
Also added a test with a valid Mach-O file with a symbol table
load command where the number of symbols is zero that shows
the report_fatal_error() is not called.
llvm-svn: 258576
but to return object_error::parse_failed. Then made the code in llvm-nm
do for Mach-O files what is done in the darwin native tools which is to
print "bad string index" for bad string indexes. Updated the error message
in the llvm-objdump test, and added tests to show llvm-nm prints
"bad string index" and a test to print the actual bad string index value
which in this case is 0xfe000002 when printing the fields as raw hex.
llvm-svn: 258520
but to return object_error::parse_failed. Then made the code in llvm-nm
do for Mach-O files what is done in the darwin native tools which is to
print "(?,?)" or just "s" for bad section indexes. Also added a test to show
it prints the bad section index of "42" when printing the fields as raw hex.
llvm-svn: 258434
Some architecture specific ELF section flags might have the same value
(for example SHF_X86_64_LARGE and SHF_HEX_GPREL) and we have to check
machine architectures to select an appropriate set of possible flags.
The patch selects architecture specific flags into separate arrays
`ElfxxxSectionFlags` and combines `ElfSectionFlags` and `ElfxxxSectionFlags`
before pass to the `StreamWriter::printFlags()` method.
Differential Revision: http://reviews.llvm.org/D16269
llvm-svn: 258334
MIPS 32-bit ABI uses REL relocation record format to save dynamic
relocations. The patch teaches llvm-readobj to show dynamic relocations
in this format.
Differential Revision: http://reviews.llvm.org/D16114
llvm-svn: 258001
We always create archives with just he filename as the member name, but
other archives can put a more complicated path in there.
This patches handles it by computing just the filename as we do when
adding a new member.
If storing the path is important for some reason, we should probably
have an orthogonal option for doing that and do it for both old and new
members.
Fixes pr25877.
llvm-svn: 256001
A manipulation (in this case, mkdir) can make slack between creating and touching %t.older/evenlen.
I would make this rewrote with python if this were still unstable.
llvm-svn: 254965
Note, this was reviewed (and more details are in) http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20151109/312083.html
These intrinsics currently have an explicit alignment argument which is
required to be a constant integer. It represents the alignment of the
source and dest, and so must be the minimum of those.
This change allows source and dest to each have their own alignments
by using the alignment attribute on their arguments. The alignment
argument itself is removed.
There are a few places in the code for which the code needs to be
checked by an expert as to whether using only src/dest alignment is
safe. For those places, they currently take the minimum of src/dest
alignments which matches the current behaviour.
For example, code which used to read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* %dest, i8* %src, i32 500, i32 8, i1 false)
will now read:
call void @llvm.memcpy.p0i8.p0i8.i32(i8* align 8 %dest, i8* align 8 %src, i32 500, i1 false)
For out of tree owners, I was able to strip alignment from calls using sed by replacing:
(call.*llvm\.memset.*)i32\ [0-9]*\,\ i1 false\)
with:
$1i1 false)
and similarly for memmove and memcpy.
I then added back in alignment to test cases which needed it.
A similar commit will be made to clang which actually has many differences in alignment as now
IRBuilder can generate different source/dest alignments on calls.
In IRBuilder itself, a new argument was added. Instead of calling:
CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, /* isVolatile */ false)
you now call
CreateMemCpy(Dst, Src, getInt64(Size), DstAlign, SrcAlign, /* isVolatile */ false)
There is a temporary class (IntegerAlignment) which takes the source alignment and rejects
implicit conversion from bool. This is to prevent isVolatile here from passing its default
parameter to the source alignment.
Note, changes in future can now be made to codegen. I didn't change anything here, but this
change should enable better memcpy code sequences.
Reviewed by Hal Finkel.
llvm-svn: 253511
Also adds a 'trivial' ELF file. This was generated by assembling
and linking a file with the symbol main which contains a single
return instruction.
llvm-svn: 251096
This patch includes a fix for a llvm-readobj test. With this patch,
the tool does no longer print out COFF headers for the short import
file, but that's probably desirable because the header for the short
import file is dummy.
llvm-svn: 246283
COFF short import files are special kind of files that contains only
DLL-exported symbol names. That's different from object files because
it has no data except symbol names.
This change implements a SymbolicFile interface for the short import
files so that symbol names can be accessed through that interface.
llvm-ar is now able to read the file and create symbol table entries
for short import files.
llvm-svn: 246276
In tree they are only used by llvm-readobj, but it is also used by
https://github.com/mono/CppSharp.
While at it, add some missing error checking.
llvm-svn: 244320
lld might end up using a small part of this, but it will be in a much
refactored form. For now this unblocks avoiding the full section scan in the
ELFFile constructor.
This also has a (very small) error handling improvement.
llvm-svn: 244282
This makes llvm-nm consistent with binutils nm on executables and DLLs.
For a vanilla hello world executable, the address of main should include
the default image base of 0x400000.
llvm-svn: 243755
llvm-readobj exists for testing llvm. We can safely stop the program
the first time we know the input in corrupted.
This is in preparation for making it handle a few more broken files.
llvm-svn: 242656
For now the Archive owns the buffers of the thin archive members.
This makes for a simple API, but all the buffers are destructed
only when the archive is destructed. This should be fine since we
close the files after mmap so we should not hit an open file
limit.
llvm-svn: 242215
They should probably be created on anything that is not windows or linux, but I will
test on freebsd before changing that.
With this it is possible to bootstrap with llvm-ar instead of ar+ranlib on OS X.
llvm-svn: 241849
It looks like ld64 requires it. With this we seem to be able to bootstrap using
llvm-ar+/usr/bin/true instead of ar+ranlib (currently on stage2).
llvm-svn: 241842
No support for the symbol table yet (but will hopefully add it today).
We always use the long filename format so that we can align the member,
which is an advantage of the BSD format.
llvm-svn: 241721
Use AddressAlign field's value to properly align sections content in the
yaml2obj tool. Before this change the yaml2obj ignored AddressAlign and
always aligned section on 16 bytes boundary.
llvm-svn: 241674
getSymbolValue now returns a value that in convenient for most callers:
* 0 for undefined
* symbol size for common symbols
* offset/address for symbols the rest
Code that needs something more specific can check getSymbolFlags.
llvm-svn: 241605
They are implemented like that in some object formats, but for the interface
provided by lib/Object, SF_Undefined and SF_Common are different things.
This matches the ELF and COFF implementation and fixes llvm-nm for MachO.
llvm-svn: 241587
When talking about the virtual address of sections the coff spec says:
... for simplicity, compilers should set this to zero. Otherwise, it is an
arbitrary value that is subtracted from offsets during relocation.
We don't currently subtract it, so check that it is zero.
If some producer does create such files, we can change getRelocationOffset
instead.
llvm-svn: 241447
SHT_NOBITS sections do not have content in an object file. Now the yaml2obj
tool does not accept `Content` field for such sections, and the obj2yaml
tool does not attempt to read the section content from a file.
Restore r241350 and r241352.
llvm-svn: 241377
r241350 broke lld tests.
r241352 depends on r241350.
Original messages:
"[ELFYAML] Fix handling SHT_NOBITS sections by obj2yaml/yaml2obj tools"
"[ELFYAML] Make the Size field for .bss section optional"
llvm-svn: 241354
SHT_NOBITS sections do not have content in an object file. Now yaml2obj
tool does not accept `Content` field for such sections, and obj2yaml
tool does not attempt to read the section content from a file.
llvm-svn: 241350
Kevin Enderby