This commit is the final step in ensuring all the pipes commit what they
should. It also asserts this actually happens, enabling us to easily
catch future problems.
This commit introduces new tags to specify how LLVMContainer should
deduplicate sets of equivalent functions, typically managed by an
`OpaqueFunctionPool`.
This commit introduces a function to obtain the name assigned to a
`llvm::Function` associated to a `model::Function`. This simplifies the
codebase but also enables us to introduce an option to produce
human-friendly names for debugging/testing purposes.
Before this commit, we used to attach to call site a metadata to trace
back the call site to the CFG (i.e., `FunctionMetadata`).
This led several passes in revng-c to depend on `FunctionMetadata` just
for this.
This commit, attaches to call sites a reference to the prototype itself
(on the `revng.prototype` metadata), breaking many of such dependencies.
This comit propagates the deduced info about inputs and outputs of pipes
all the way up to the runner, so that the requested output of a pipe can
be passed to its invocation.
Various parts of revng replace `llvm::GlobalVariable`s representing CSVs
with Allocal/Load/Store. In particular, these are PromoteCSV,
RootAnalyzer and PromoteGlobalToLocalVars.
Before this commit, those places were sloppy when replacing CSVs with
Alloca/Load/Store, and did that iterating on a container sorted by
pointers. This caused Alloca/Load/Store to be emitted in different order
accross runs, which in turn caused more non-determinism down the
pipeline.
This commit fixes the non-deterministic behavior, sorting CSVs based on
their names, which should always be present and deterministic.
This commit switches the approach with which we run the ABI analyses: we
now run them until we reach a fixed point. This enables proper
interprocedural propagation of arguments and return values.
Basically, we now inject reads before call sites, so that, if a function
immediately calls another one, the arguments of the callee are
propagated to the caller.
This commit also updates the logic with which we propagate function
prototypes (and names) to callers. The main advantage of this, is that
function wrappers (in particular, PLT entries) now have the same name as
the function they wrap.
This commit drops calls to `_init_$CPU_STATE` for non-general purpose
registers. Instead, these part of the CPU state are initialized using
the initializer of the CSV, which is in turn provided by QEMU.
This enables us to properly initialize as appropriate fields such as
x86-64's DF flag.
During this phase (EnforceABI) the binary is not meant to be run
so the debug info is not useful anymore, so we are striping them
now in order to avoid taking care of them during the pipeline.
This commit improves the formalization of how we handle names.
The main changes are:
* Now `_` is a reserved prefix and all the generated names start with
`_`.
* The model verification routine now checks that `CustomName`s in the
global scope do not collide with any local namespace (e.g., fields of
a `StructType`).
* We changed the prefix `prefix_` to `unreserved_` to better convey the
fact that the prefix has been introduce to use an non-reserved name.
Before this commit, we were blinding adding the `nomerge` attribute to
function calls. Now we copy attributes over, so we preserve all the
attributes.
In this way the only place where we add the `nomerge` attribute becomes
Isolate.
Alessandro Di Federico