This commit updates the `DataFlowNode` data structure used in
`TypeShrinking` to be compatible with the newer version `GenericGraph`
provided by revng.
The change basically encompasses inverting the inheritance and dropping
CRTP.
- Use uint32_t
- Define Top as uin32_t max
- Fix copyright notice
- Use using namespace llvm in cpp files
- Change hasSideEffects to isDataFlowSink
- Outline isAddLike
- Add option to ignore certain analysis results
This commits adds two passes
- FilterForDecompilationFunctionPass deletes the body of a Function if
it's not a isolated function produced by revng
- FilterForDecompilationModulePass deletes all the bodies of the
functions that are not isolated functions generated by revng
These passes are used at the beginning of the decompilation pipeline, to
prevent all the passes of the decompilation pipeline to run on root and
other big functions coming from QEMU that do not need to be decompiled.
This fixes an issue causing crashes when calling the public API
`decompileFunction`, that was internally adding a `MakeEnvNullPass`
(formerly a `ModulePass`) to a `FunctionPassManager.
This pass substitutes the `@env` global variable with a null pointer
`@env` is a pointer to the CPU state in QEMU, and is not meant to be
visible in the decompiled code.
This pass is used to remove all references to it before decompilation.
When the `Successor` field is consumed to create the `Sequence` nodes,
we blank the field so that we do not have redundant information in our
graph representation.
Change the AST debug printing from a recursive descent on the AST nodes
in the graph, to an iterative printing of respectively nodes and their
outgoing edges.
Also, we now print the edge going to the `Successor` field, if present.
Reorganize the AST dot printing in order to use LLVM facilities for
files handling. In addition, clean up the code, and add a function
(useful in debug) in order to dump the dot of and AST from GDB (accepts
a `char *` instead of a `std::string`.
Now, when the `debug-log=restructure` flag is active, debug graphs are
organized in a more rational way.
First of all, all the graphs are now put in a single directory, and are
divided first by function name and then by type.
Also, as in the case of the tiling debug graphs, their name is more
consistent with the rest of the codebase.
We now craft a new decompilation pipeline. We remove the exceptions
introduced as fallbacks to preserve the semantics, and we perform passes
of `dce` and `simplifycfg` to remove all the superfluos basic block
remaining after this change. To do this, we need an additional pass that
removes also the calls to the `llvm.assume` intrinsic, and another pass
of `dce` to remove all the dead uses.
In addition, we also remove dead stores to the `cpu_loop_exiting` global
variable in order to improve the decompiled code.
As a byproduct of this, we remove also the dependency from the
`-remove-pc-stores` pass, since its jobs is included by the changes
mentioned above.
Alessandro Di Federico