Since isort 5.11.0 if a import statement ends with a trailing comma it's
excluded for sorting, which makes the black-formatted import lines
unformatted by isort. Disable this behavior in the config so all import
lines are sorted as they should.
Smoke test that exercises the linux/x86-64 path: feeds malloc/calloc/
realloc plus a NonExistentFunction through the analysis and asserts that
the typed symbols pick up a prototype while the unknown one does not.
Remove the workaround that suppressed the redundant
self-assignment that the pass now occasionally introduces in
non-legacy mode.
The remaining self-assignments are not bugs but sub-optimal C
generation, so we just disable the -Wself-assign warning in the
tests.
The sub-optimal code generation comes from passes that emit local
variables (allocas) before conversion to Clift, e.g. STS and
ExitSSA (with more planned). Each of these passes generates local
variables independently and they don't know about each other; the
order between them might also be swapped in the future. The only
clean fix is to unify them into a single transformation pass that
takes the results of multiple analyses (in the LLVM sense) and
emits local variables once. We have plans to do that, and when
it's done the warning can be re-enabled.
Introduce a new canonicalisation pass that forces a small set of
exponential-dataflow-prone instructions (SelectInst plus the FShl
and FShr intrinsic patterns) to be stored into a dedicated local
variable. Without this, expanding their value into C expressions
during decompilation can blow up into exponential path enumeration
on real binaries.
This is a temporary workaround. A more principled split of
pathological dataflows is planned and will replace this pass.
The macro is no longer necessary: the code now ensures we never
need to assign anything to an array, which would be ill-advised
nevertheless given that array-typed rvalues in C immediately
decay to pointers.
The macro is no longer necessary: the code now ensures we never
need to bitcast anything to an array, which would be ill-advised
nevertheless given that array-typed rvalues in C immediately
decay to pointers.
Run -strip-dead-prototypes as part of the LLVM-pass list invoked
just before the Clifter, so that all unused helpers are stripped
away. In particular, this prevents some LLVM intrinsics that
return structs containing i1 (e.g. the overflow intrinsics) from
ending up in the C output and tripping later passes.
assign_array is necessary as a fallback for when the decompiled C
code may need assignments among array types. bit_cast_to_array is
necessary because when the target type of a bitcast is an array
the regular bit_cast macro is not enough.
Rework primitive-types.h so that the various bit_cast macros share
a single implementation based on `typeof`/`__typeof__`. As a
consequence both keywords are added to the model's reserved-name
set so that user identifiers cannot collide with them.
Add a canonicalisation pass that rewrites extractvalue from a
pointer-returning struct as an i8 GEP plus a load. Together with
ArithmeticToGEP this lets later passes consume the result through
the same GEP-based interface they use for ordinary memory accesses.
Introduce the ArithmeticToGEP canonicalisation pass. It detects
pointers (LLVM-typed pointer values, model pointers flagged by the
"revng.pointers" metadata, and pointer-tagged extract values) and
rewrites integer arithmetic computed on top of them as i8 GEPs,
followed by a ptrtoint when the original use needs an integer.
For each obvious pointer the pass also walks backwards through Add
chains and disambiguates the pointer operand of each Add when the
other operand cannot be a pointer, so the rewrite extends to integer
arithmetic that only later flows into a pointer use.
This commit introduces an analysis to import prototypes from a SQLite
database of well-known prototypes, typically built from debug info of
operating systems.
This analysis supersedes import-well-known-models.
Refactor the binary import and dependency resolution infrastructure to
support multiple platforms (Linux, Windows, macOS) via a
configuration-driven root system.
Major changes:
* Overhaul PDB and DWARF importers for platform-aware debug info
loading.
* Refactor LDDTree into a template-based architecture with
platform-specific implementations (ELF, PE/COFF).
* Mostly rewrite the PDB importer, which had significant limitations.
Rework the python mixin infrastructure for the model. Mixins are now
specified explicitly instead of using the `ast` module. The mixins are
loaded relative to the generated python file, this allows to have two
models: `revng.model` and `revng.project.model`. The latter is augmented
via mixins to have project-specific facilities such as `get_artifact`
and artifact accessors.
Giacomo Vercesi