Before this commit, the logic to generate all the emitted C forward
declarations (types, global variables, and functions) that has to be
printed before each decompiled function was scattered across three
classes: FuncDeclCreationAction, TypeDeclCreationAction, and
GlobalDeclCreationAction.
These are all gone now, because the scattered logic was very confusing
to follow. Now we only have a single class that takes care of
declarations with global scope: DeclCreator.
Thanks to this, I was able to drop a bunch of useless layers of software
engineering used to shape the creation of the declaration as if it was
some kind of clang ASTConsumer, which is pointless.
This class handles the creation of type declarations in clang's AST, and
holds the relationships between llvm Types and Values with those clang's
type declarations.
Before this commit, we assigned names to struct types without looking at
the function names of which they were return types.
Now we do, so that the name of the generated type for the function `f`
is `f_ret_type`.
This also fixes errors when reparsing the generated C code, where the
names of the struct types did not match.
With this commit, the declarations of local variables and function
parameters now use the name of the associated `llvm::Value` if present,
instead of always using the prefix "param_" or "var_".
Replicate the changes made by this commit
f2a0df309f78e1b5d7c5f81ada5110523644559e perfomed by Pietro on the
branch containing the development fixes for `revng-c`.
Handle the emission of variadic functions (such as the
`indirect_handler` helper function) both in regards if declaration and
definition.
Handle also `undef` values in calls to the `indirect_handler` function.
Pietro Fezzardi