Author: edelsohn Branch: extradoc Changeset: r4096:3b2a3ebfb225 Date: 2012-02-20 20:03 -0500 http://bitbucket.org/pypy/extradoc/changeset/3b2a3ebfb225/
Log: merge diff --git a/planning/separate-compilation.txt b/planning/separate-compilation.txt new file mode 100644 --- /dev/null +++ b/planning/separate-compilation.txt @@ -0,0 +1,81 @@ +Separate Compilation +==================== + +Goal +---- + +Translation extension modules written in RPython. +The best form is probably the MixedModule. + +Strategy +-------- + +The main executable (bin/pypy-c or libpypy-c.dll) exports RPython +functions; this "first translation" also produces a pickled object +that describe these functions: signatures, exception info, etc. + +It will probably be necessary to list all exported functions and methods, +or mark them with some @exported decorator. + +The translation of an extension module (the "second translation") will +reuse the information from the pickled object; the content of the +MixedModule is annotated as usual, except that functions exported by +the main executable are now external calls. + +The extension module simply has to export a single function +"init_module()", which at runtime uses space operations to create and +install a module. + + +Roadmap +------- + +* First, a framework to test and measure progress; builds two + shared libraries (.so or .dll): + + - the first one is the "core module", which exports functions + - that can be called from the second module, which exports a single + entry point that we call call with ctypes. + +* Find a way to mark functions as "exported". We need to either + provide a signature, or be sure that the functions is somehow + annotated (because it is already used by the core interpreter) + +* Pass structures (as opaque pointers). At this step, only the core + module has access to the fields. + +* Implement access to struct fields: an idea is to use a Controller + object, and redirect attribute access to the ClassRepr computed by + the first translation. + +* Implement method calls, again with the help of the Controller which + can replace calls to bound methods with calls to exported functions. + +* Share the ExceptionTransformer between the modules: a RPython + exception raised on one side can be caught by the other side. + +* Support subclassing. Two issues here: + + - isinstance() is translated into a range check, but these minid and + maxid work because all classes are known at translation time. + Subclasses defined in the second module must use the same minid + and maxid as their parent; isinstance(X, SecondModuleClass) should + use an additional field. Be sure to not confuse classes + separately created in two extension modules. + + - virtual methods, that override methods defined in the first + module. + +* specialize.memo() needs to know all possible values of a + PreBuildConstant to compute the results during translation and build + some kind of lookup table. The most obvious case is the function + space.gettypeobject(typedef). Fortunately a PBC defined in a module + can only be used from the same module, so the list of prebuilt + results is probably local to the same module and this is not really + an issue. + +* Integration with GC. The GC functions should be exported from the + first module, and we need a way to register the static roots of the + second module. + +* Integration with the JIT. _______________________________________________ pypy-commit mailing list pypy-commit@python.org http://mail.python.org/mailman/listinfo/pypy-commit
