Commit Graph

31 Commits

Author SHA1 Message Date
David Blaikie 60fbd3bdb7 llvm-dwp: Handle dwo files produced by GCC
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
2016-04-05 20:16:38 +00:00
David Blaikie 9b49256fa8 llvm-dwp: Simplify hashing code a bit
llvm-svn: 265426
2016-04-05 17:51:40 +00:00
David Blaikie 4dd03f0e12 llvm-dwp: Include the dwo name (if available) when diagnosing duplicate CU IDs from dwp input files
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
2016-03-26 20:32:14 +00:00
David Blaikie ce7c6cfe0e llvm-dwp: Coalesce code for reading the CU's DW_AT_GNU_dwo_id and DW_AT_name
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
2016-03-24 22:17:08 +00:00
David Blaikie f72dbc101c llvm-dwp: Add missing copyright notice to llvm-dwp.cpp
Addressing feedback on IRC by Sean Silva.

llvm-svn: 262416
2016-03-01 22:29:00 +00:00
David Blaikie ddb27369a0 Revert "llvm-dwp: Keep ObjectFiles alive until object emission their contents can be referenced directly rather than copied"
Accidentally committed.

This reverts commit r262389.

llvm-svn: 262395
2016-03-01 21:24:04 +00:00
David Blaikie 578f2cdd2d llvm-dwp: Keep ObjectFiles alive until object emission their contents can be referenced directly rather than copied
llvm-svn: 262389
2016-03-01 20:40:02 +00:00
David Blaikie f1958da1c3 llvm-dwp: provide diagnostics for duplicate DWO IDs
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
2016-02-26 07:30:15 +00:00
David Blaikie 5d6d4dc306 llvm-dwp: Support empty .dwo files
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
2016-02-26 07:04:58 +00:00
David Blaikie 852c02baf9 llvm-dwp: Improve performance (N^2 to amortized N) by using a MapVector instead of linear searches through a vector
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
2016-02-19 21:09:26 +00:00
David Blaikie 9a5d3645b4 llvm-dwp: Don't test compression when zlib isn't available
llvm-svn: 261298
2016-02-19 02:03:45 +00:00
David Blaikie 74f5b28211 llvm-dwp: Support compressed input
llvm-svn: 261296
2016-02-19 01:51:44 +00:00
Benjamin Kramer e593094a15 Add parentheses around arithmetic in operand of '|'.
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
2016-02-18 13:23:17 +00:00
David Blaikie 8bce5a053d llvm-dwp: Support for type units when merging DWPs into larger DWPs
llvm-svn: 261072
2016-02-17 07:00:24 +00:00
David Blaikie 376b33a0d0 Fix the hash function.
llvm-svn: 261071
2016-02-17 07:00:22 +00:00
David Blaikie 23919372d1 [llvm-dwp] Merge cu_index from DWPs
This is almost feature complete - just missing tu_index merging now.

llvm-svn: 259971
2016-02-06 01:15:26 +00:00
David Majnemer 03e2cc3007 [MC, COFF] Support link /incremental conditionally
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
2015-12-21 22:09:27 +00:00
David Blaikie f5cb6279a6 [llvm-dwp] Deduplicate type units
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
2015-12-14 07:42:00 +00:00
David Blaikie c3826da895 [llvm-dwp] Sink debug_types.dwo emission into the code parsing the type signatures (NFC)
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
2015-12-09 21:02:33 +00:00
David Blaikie 9e51c844da [llvm-dwp] Add coverage for both the presence and absence of type units, and fix/remove the emission of a broken tu_index when no type units are present
llvm-svn: 254833
2015-12-05 03:41:53 +00:00
David Blaikie 2ed678c6af [llvm-dwp] clang-format this to catch anything I've missed along the way
llvm-svn: 254828
2015-12-05 03:06:30 +00:00
David Blaikie 24c8ac93f3 [llvm-dwp] Support debug_tu_index
llvm-svn: 254827
2015-12-05 03:05:45 +00:00
David Blaikie 7c4ffe018a [llvm-dwp] Implement the required on-disk probed hash table
llvm-svn: 254770
2015-12-04 21:30:23 +00:00
David Blaikie b7020255e5 [llvm-dwp] Include the debug_line.dwo section
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
2015-12-04 21:16:42 +00:00
David Blaikie ad07b5d65e [llvm-dwp] Retrieve the DWOID from the CU for the cu_index entry
llvm-svn: 254731
2015-12-04 17:20:04 +00:00
David Blaikie b3757c008b [llvm-dwp] Include only the non-empty columns in the cu_index
llvm-svn: 254555
2015-12-02 22:01:56 +00:00
David Blaikie b073cb9be2 [llvm-dwp] Emit a rather fictional debug_cu_index
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
2015-12-02 06:21:34 +00:00
David Blaikie bb94e440d5 [llvm-dwp] Deduplicate strings in the debug_str.dwo section
Also, ensure that references to those strings in debug_str_offsets.dwo
correctly refer to the deduplicated strings.

llvm-svn: 254441
2015-12-01 19:17:58 +00:00
David Blaikie 98ad82a6a1 [llvm-dwp] Correctly update debug_str_offsets.dwo when linking dwo files
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
2015-12-01 18:07:07 +00:00
David Blaikie 242b948817 [llvm-dwp] Initial partial prototype
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
2015-12-01 00:48:39 +00:00
David Blaikie df05525d86 llvm-dwp: Initial layout
llvm-svn: 254354
2015-12-01 00:48:34 +00:00