On Wed, Apr 13, 2011 at 10:21:06AM +0200, Jens Axel Søgaard wrote: > 2011/4/13 Hendrik Boom <hend...@topoi.pooq.com>: > > On Tue, Apr 12, 2011 at 08:17:02PM -0600, Jay McCarthy wrote: > >> LLVM definitely supports tail-calls and GC. > >> > >> TCO: > >> http://llvm.org/docs/CodeGenerator.html#tailcallopt > > > > Good to hear. What does the restriction > > > > when generating GOT/PIC code only module-local calls (visibility = > > hidden or protected) are supported. > > mean? > > A tail-call to a function located to another module will use stack space. > But that's not too helpful -what is a module? > > The docs are here: > http://docs.huihoo.com/llvm/LangRef.html#modulestructure > > It says: > > LLVM programs are composed of "Module"s, each of which is a translation > > unit of the input programs. > > Each module consists of functions, global variables, and symbol table > > entries. Modules may be > > combined together with the LLVM linker, which merges function (and global > > variable) definitions, > > resolves forward declarations, and merges symbol table entries. > > In the case of a C compiler it could mean one of: > * a module corresponds to a source file > * a module corresponds to the source files that turn into one linker unit > Which one is the correct one depends on how the C compiler uses the > LLVM backend. > > I do not know which is correct for llvm-gcc.
Isn't is possible to tailcall a fumction dynamically, i.e., one fetched form a variable or some such? One for which you don't know statically what's being called,, let alone whether it's in the same module? Possibly even one thta has been JIT-compiled, considering that LLVM does have a JIT mode? -- hendrik _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
