Use Coq strings instead of idents to name external and builtin functions.

The AST.ident type represents source-level identifiers as unique positive numbers.  However, the mapping identifiers <-> AST.ident differs between runs of CompCert on different source files.  This is problematic when we need to produce or recognize external functions and builtin functions with fixed names, for example:
* in $ARCH/Machregs.v to define the register conventions for builtin functions;
* in the VST program logic from Princeton to treat thread primitives specially.

So far, we used AST.ident_of_string to recover the ident associated with a string.  However, this function is defined in OCaml and doesn't execute within Coq.  This is a problem both for VST and for future executability of CompCert within Coq.

This commit replaces "ident" by "string" in the arguments of EF_external, EF_builtin, EF_inline_asm, EF_annot, and EF_annot_val.  This provides stable names for externals and builtins, as needed.  For inline asm and annotations, it's a matter of taste, but using strings feels more natural.  EF_debug keeps using idents, since some kinds of EF_debug annotations talk about program variables.

1 files changed, 3 insertions, 3 deletions

diff --git a/driver/Interp.ml b/driver/Interp.ml
index f453af95..579b936d 100644
--- a/driver/Interp.ml
+++ b/driver/Interp.ml
@@ -59,7 +59,7 @@ let print_eventval_list p = function
 let print_event p = function
   | Event_syscall(id, args, res) ->
       fprintf p "extcall %s(%a) -> %a"
-                (extern_atom id)
+                (camlstring_of_coqstring id)
                 print_eventval_list args
                 print_eventval res
   | Event_vload(chunk, id, ofs, res) ->
@@ -74,7 +74,7 @@ let print_event p = function
                 print_eventval arg
   | Event_annot(text, args) ->
       fprintf p "annotation \"%s\" %a"
-                (extern_atom text)
+                (camlstring_of_coqstring text)
                 print_eventval_list args
 
 (* Printing states *)
@@ -387,7 +387,7 @@ let rec convert_external_args ge vl tl =
   | _, _ -> None
 
 let do_external_function id sg ge w args m =
-  match extern_atom id, args with
+  match camlstring_of_coqstring id, args with
   | "printf", Vptr(b, ofs) :: args' ->
       extract_string m b ofs >>= fun fmt ->
       print_string (do_printf m fmt args');