Summary: getSubroutineName is currently only used by llvm-symbolizer, thus add a binary test containing a cross-cu inlining example.
Reviewers: samsonov, dblaikie
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D5394
llvm-svn: 218245
To reduce the size of -gmlt data, skip the subprograms without any
inlined subroutines. Since we've now got the ability to make these
determinations in the backend (funnily enough - we added the flag so we
wouldn't produce ranges under -gmlt, but with this change we use the
flag, but go back to producing ranges under -gmlt).
Instead, just produce CU ranges to inform the consumer which parts of
the code are described by this CU's line table. Tools could inspect the
line table directly to compute the range, but the CU ranges only seem to
be about 0.5% of object/executable size, so I'm not too worried about
teaching llvm-symbolizer that trick just yet - it's certainly a possible
piece of future work.
Update an llvm-symbolizer test just to demonstrate that this schema is
acceptable there (if it wasn't, the compiler-rt tests would catch this,
but good to have an in-llvm-tree test for llvm-symbolizer's behavior
here)
Building the clang binary with -gmlt with this patch reduces the total
size of object files by 5.1% (5.56% without ranges) without compression
and the executable by 4.37% (4.75% without ranges).
llvm-svn: 218129
Previous algorithm for constructing [Address ranges]->[Compile Units]
mapping was wrong. It somewhat relied on the assumption that address ranges
for different compile units may not overlap. It is not so.
For example, two compile units may contain the definition of the same
linkonce_odr function. These definitions will be merged at link-time,
resulting in equivalent .debug_ranges entries for both these units
Instead of sorting and merging original address ranges (from .debug_ranges
and .debug_aranges), implement a different approach: save endpoints
of all ranges, and then use a sweep-line approach to construct
the desired mapping. If we find that certain address maps to
several compilation units, we just pick any of them.
llvm-svn: 210860
Turns out that DW_AT_ranges_base attribute sets the offset for
DW_AT_ranges values specified in the .dwo file, but not for DW_AT_ranges specified
in the skeleton compile unit DIE in the main executable. This is extremely confusing,
and would hopefully be fixed in DWARF-5 when it's finalized. For now this
behavior makes sense, as otherwise Fission would break DWARF consumers who
doesn't know anything about DW_AT_ranges_base.
llvm-svn: 210809
Change --functions option in llvm-symbolizer tool to accept
values "none", "short" or "linkage". Update the tests and docs
accordingly.
llvm-svn: 209050
This is important for symbolizing executables with debug info in
unavailable .dwo files. Even if all DIE entries are missing, we can
still symbolize an address: function name can be fetched from symbol table,
and file/line info can be fetched from line table.
llvm-svn: 206665
Alexey Samsonov