Richard Smith identified this in post commit review of r270466. The
string sections in particular (in the future, possibly all sections - so
I'm not going to bother pulling out just the string sections for the
extra lifetime handling right now) need to remain valid during
processing of all inputs so that elements of the DWPStringPool can be
looked up repeatedly without having to make in-memory copies of string
contents in the noncompressed case (more common in dwp+dwp merge steps
where the memory is a bigger problem because the files are larger).
Using the SmallVector (or any vector) a reallocation on push_back could
cause any of the nested SmallStrings in small mode to move in memory and
invalid pointers to their contents. Using a deque the SmallStrings will
never move around since no elements are removed from the container.
llvm-svn: 270797
Now that the string pool is referential rather than maintaining its own
copy of string data, compressed sections (well, technically only the
debug_str section*) need to be preserved for the lifetime of the pool to
match.
* I'm not currently optimizing for memory footprint with compressed
input - the major memory limit I'm hitting is on dwp+dwp merge steps
and we aren't currently compressing contents in dwp files, just in the
.dwo inputs.
llvm-svn: 270462
MC only needs to know if the output is PIC or not. It never has to
decide about creating GOTs and PLTs for example. The only thing that
MC itself uses this information for is expanding "macros" in sparc and
mips. The rest I am pretty sure could be moved to CodeGen.
This is a cleanup and isolates the code from future changes to
Reloc::Model.
llvm-svn: 269909
This diagnostic could be improved by adding the name of the input file
containing the invalid data and/or some information about how to
identify the specific offending attribute/tag in the input. But that's
not an immediate priority as these corner cases of invalid input
shouldn't come up too often.
llvm-svn: 269727
The diagnostic could be improved a bit to include information about
which input file had the mistake (& which unit (counted, since the name
of the unit won't be accessible) within the input).
llvm-svn: 269723
Actually use the error return path rather than printing the duplicate
information then a separate error. But also just tidy up/deduplicate
some of the code for generating the diagnostic text.
llvm-svn: 269692
Removed some unused headers, replaced some headers with forward class declarations.
Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'
Patch by Eugene Kosov <claprix@yandex.ru>
Differential Revision: http://reviews.llvm.org/D19219
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266595
Produce the first specific error message for a malformed Mach-O file describing
the problem instead of the generic message for object_error::parse_failed of
"Invalid data was encountered while parsing the file”. Many more good error
messages will follow after this first one.
This is built on Lang Hames’ great work of adding the ’Error' class for
structured error handling and threading Error through MachOObjectFile
construction. And making createMachOObjectFile return Expected<...> .
So to to get the error to the llvm-obdump tool, I changed the stack of
these methods to also return Expected<...> :
object::ObjectFile::createObjectFile()
object::SymbolicFile::createSymbolicFile()
object::createBinary()
Then finally in ParseInputMachO() in MachODump.cpp the error can
be reported and the specific error message can be printed in llvm-objdump
and can be seen in the existing test case for the existing malformed binary
but with the updated error message.
Converting these interfaces to Expected<> from ErrorOr<> does involve
touching a number of places. To contain the changes for now use of
errorToErrorCode() and errorOrToExpected() are used where the callers
are yet to be converted.
Also there some were bugs in the existing code that did not deal with the
old ErrorOr<> return values. So now with Expected<> since they must be
checked and the error handled, I added a TODO and a comment:
“// TODO: Actually report errors helpfully” and a call something like
consumeError(ObjOrErr.takeError()) so the buggy code will not crash
since needed to deal with the Error.
Note there is one fix also needed to lld/COFF/InputFiles.cpp that goes along
with this that I will commit right after this. So expect lld not to built
after this commit and before the next one.
llvm-svn: 265606
To start with, handle DW_FORM_string names. Follow up commit will handle
the interesting quirk with type units I was originally aiming for here.
llvm-svn: 265452
If you're building dwps from other dwps, it can be hard to track down a
duplicate CU ID if it comes from two compilations of the same file in
different modes, etc. By including the .dwo path (which is hopefully
more unique than the file path) it can help track down where the
duplicates came from.
llvm-svn: 264520
Going to be reading the DW_AT_GNU_dwo_name shortly as well, and there
was already enough duplication here that it was worth refactoring
rather than adding even more.
llvm-svn: 264350
These diagnostics aren't perfect - in the case of merging several dwos
into dwps and those dwps into more dwps - just getting the message about
the original source file name might not be much help (since it's the
same in both dwos, by definition - but doesn't tell you which chain of
dwps to backtrack)
It might be worth adding the DW_AT_dwo_id to the split debug info to
improve the diagnostic experience - might help track down the duplicates
better.
llvm-svn: 261988
Though a bit odd, this is handy for a few reasons - for example, in a
build system that wants consistent input/output of build steps, but
where split-dwarf might be overriden/disabled by the user on a per-file
basis.
llvm-svn: 261987
Figured this would be a problem, but didn't want to jump the gun - large
inputs demonstrate it pretty easily (mostly for type units, but might as
well do the same for CUs too). A random sample 6m27s -> 27s change.
Also, by checking this up-front for CUs (rather than when building the
cu_index) we can probably provide better error messages (see FIXMEs),
hopefully providing the name of the CUs rather than just their
signature.
llvm-svn: 261364
This avoids a operator precedence warning for mixing + and | in an
expression. I checked that this matches the definition in the Split
DWARF proposal.
Patch by Cong Liu!
Differential Revision: http://reviews.llvm.org/D17375
llvm-svn: 261207
Today, we always take into account the possibility that object files
produced by MC may be consumed by an incremental linker. This results
in us initialing fields which vary with time (TimeDateStamp) which harms
hermetic builds (e.g. verifying a self-host went well) and produces
sub-optimal code because we cannot assume anything about the relative
position of functions within a section (call sites can get redirected
through incremental linker thunks).
Let's provide an MCTargetOption which controls this behavior so that we
can disable this functionality if we know a-priori that the build will
not rely on /incremental.
llvm-svn: 256203
It's O(N^2) because it does a simple walk through the existing types to
find duplicates, but that will be fixed in a follow-up commit to use a
mapping data structure of some kind.
llvm-svn: 255482
This is a preliminary change towards deduplicating type units based on
their signatures. Next change will skip emission of types when their
signature has already been seen.
llvm-svn: 255154
This probably shouldn't be generated in the .dwo file for CUs, only for
TUs, but it's in the sample .dwos (generated by clang) so dwp should
reflect that.
Arguably the DWP tool could be smart enough to know that the CUs
shouldn't need a debug_line.dwo section and skip that even when it's
legitimately generated for TUs, but that's a bit more off-book.
llvm-svn: 254767
This is very rudimentary support for debug_cu_index, but it is enough to
allow llvm-dwarfdump to find the offsets for contributions and
correctly dump debug_info.
It will need to actually find the real signature of the unit and build
the real hash table with the right number of buckets, as per the DWP
specification.
It will also need to be expanded to cover the tu_index as well.
llvm-svn: 254489
This doesn't deduplicate strings in the debug_str section, nor does it
properly wire up the index so that debug_info can /find/ these strings,
but it does correct the str_offsets specifically.
Follow up patches to address those related/next issues.
llvm-svn: 254431
This just concatenates the common DWP sections without doing any of the
fancy DWP things like:
1) update str_offsets
2) deduplicating strings
3) merging/creating cu/tu_index
Patches for these will follow shortly.
(also not sure about target triple/object file type for this tool - do I
really need a whole triple just to write an object file that contains
purely static/hardcoded bytes in each section? & I guess I should just
pick it based on the first input, maybe, rather than hardcoding for now
- but we only produce .dwo on ELF platforms with objcopy for now anyway)
llvm-svn: 254355
David Blaikie