This abstraction isn't really tied to DWARF at all! Really, we're just
loading some information from an ELF file which is useful for debugging.
That *includes* DWARF, but it also includes other information. For
instance, the other change here:
Now, if DWARF information is missing, `debug.SelfInfo.ElfModule` will
name symbols by finding a matching symtab entry. We actually already do
this on Mach-O, so it makes obvious sense to do the same on ELF! This
change is what motivated the restructuring to begin with.
The symtab work is derived from #22077.
Co-authored-by: geemili <opensource@geemili.xyz>
heap.zig: define new default page sizes
heap.zig: add min/max_page_size and their options
lib/std/c: add miscellaneous declarations
heap.zig: add pageSize() and its options
switch to new page sizes, especially in GPA/stdlib
mem.zig: remove page_size
The implementation assumed that compilation units did not overlap, which
is not the case. The new implementation uses .debug_ranges to iterate
over the requested PCs.
This partially resolves#20990. The dump-cov tool is fixed but the same
fix needs to be applied to `std.Build.Fuzz.WebServer` (sorting the PC
list before passing it to be resolved by debug info).
I am observing LLVM emit multiple 8-bit counters for the same PC
addresses when enabling `-fsanitize-coverage=inline-8bit-counters`. This
seems like a bug in LLVM. I can't fathom why that would be desireable.
* libfuzzer: close file after mmap
* fuzzer/main.js: connect with EventSource and debug dump the messages.
currently this prints how many fuzzer runs have been attempted to
console.log.
* extract some `std.debug.Info` logic into `std.debug.Coverage`.
Prepares for consolidation across multiple different executables which
share source files, and makes it possible to send all the
PC/SourceLocation mapping data with 4 memcpy'd arrays.
* std.Build.Fuzz:
- spawn a thread to watch the message queue and signal event
subscribers.
- track coverage map data
- respond to /events URL with EventSource messages on a timer
* std.debug.Dwarf: add `sortCompileUnits` along with a field to track
the state for the purpose of assertions and correct API usage.
This makes batch lookups faster.
- in the future, findCompileUnit should be enhanced to rely on sorted
compile units as well.
* implement `std.debug.Dwarf.resolveSourceLocations` as well as
`std.debug.Info.resolveSourceLocations`. It's still pretty slow, since
it calls getLineNumberInfo for each array element, repeating a lot of
work unnecessarily.
* integrate these APIs with `std.Progress` to understand what is taking
so long.
The output I'm seeing from this tool shows a lot of missing source
locations. In particular, the main area of interest is missing for my
tokenizer fuzzing example.
with debug info resolved.
begin efforts of providing `std.debug.Info`, a cross-platform
abstraction for loading debug information into an in-memory format that
supports queries such as "what is the source location of this virtual
memory address?"
Unlike `std.debug.SelfInfo`, this API does not assume the debug
information in question happens to match the host CPU architecture, OS,
or other target properties.
