Allow sail to be scripted using sail

Currently the -is option allows a list of interactive commands to be
passed to the interactive toplevel, however this is only capable of
executing a sequential list of instructions which is quite limiting.

This commit allows sail interactive commands to be invoked from sail
functions running in the interpreter which can be freely interleaved
with ordinary sail code, for example one could test an assertion at each
QEMU/GDB breakpoint like so:

$include <aarch64.sail>

function main() -> unit = {
  sail_gdb_start("target-select remote localhost:1234");
  while true do {
    sail_gdb_continue(); // Run until breakpoint
    sail_gdb_sync();     // Sync register state with QEMU
    if not(my_assertion()) {
      print_endline("Assertion failed")
    }
  }
}

1 files changed, 13 insertions, 17 deletions

diff --git a/src/slice.ml b/src/slice.ml
index 1ac390bd..83010733 100644
--- a/src/slice.ml
+++ b/src/slice.ml
@@ -361,24 +361,20 @@ let () =
   let slice_roots = ref IdSet.empty in
   let slice_cuts = ref IdSet.empty in
 
-  (fun arg ->
+  ArgString ("identifiers", fun arg -> Action (fun () ->
     let args = Str.split (Str.regexp " +") arg in
     let ids = List.map mk_id args |> IdSet.of_list in
     Specialize.add_initial_calls ids;
     slice_roots := IdSet.union ids !slice_roots
-  ) |> register_command
-         ~name:"slice_roots"
-         ~help:(sprintf ":slice_roots %s - Set the roots for %s" (arg "identifiers") (command "slice"));
+  )) |> register_command ~name:"slice_roots" ~help:"Set the roots for :slice";
 
-  (fun arg ->
+  ArgString ("identifiers", fun arg -> Action (fun () ->
     let args = Str.split (Str.regexp " +") arg in
     let ids = List.map mk_id args |> IdSet.of_list in
     slice_cuts := IdSet.union ids !slice_cuts
-  ) |> register_command
-         ~name:"slice_cuts"
-         ~help:(sprintf ":slice_cuts %s - Set the roots for %s" (arg "identifiers") (command "slice"));
+  )) |> register_command ~name:"slice_cuts" ~help:"Set the cuts for :slice";
 
-  (fun arg ->
+  Action (fun () ->
     let module NodeSet = Set.Make(Node) in
     let module G = Graph.Make(Node) in
     let g = graph_of_ast !ast in
@@ -388,10 +384,11 @@ let () =
     ast := filter_ast cuts g !ast
   ) |> register_command
          ~name:"slice"
-         ~help:(sprintf ":slice - Slice AST to the definitions which the functions given by %s depend on, up to the functions given by %s"
-                        (command "slice_roots") (command "slice_cuts"));
+         ~help:"Slice AST to the definitions which the functions given \
+                by :slice_roots depend on, up to the functions given \
+                by :slice_cuts";
 
-  (fun arg ->
+  Action (fun () ->
     let module NodeSet = Set.Make(Node) in
     let module NodeMap = Map.Make(Node) in
     let module G = Graph.Make(Node) in
@@ -409,7 +406,7 @@ let () =
          ~name:"thin_slice"
          ~help:(sprintf ":thin_slice - Slice AST to the function definitions given with %s" (command "slice_roots"));
 
-  (fun arg ->
+  ArgString ("format", fun arg -> Action (fun () ->
     let format = if arg = "" then "svg" else arg in
     let dotfile, out_chan = Filename.open_temp_file "sail_graph_" ".gz" in
     let image = Filename.temp_file "sail_graph_" ("." ^ format) in
@@ -418,9 +415,8 @@ let () =
     let _ = Unix.system (Printf.sprintf "dot -T%s %s -o %s" format dotfile image) in
     let _ = Unix.system (Printf.sprintf "xdg-open %s" image) in
     ()
-  ) |> register_command
-         ~name:"graph"
-         ~help:(sprintf ":graph %s - Draw a callgraph using dot in %s (default svg if none provided), and open with xdg-open"
-                        (arg "format") (arg "format"));
+  )) |> register_command
+          ~name:"graph"
+          ~help:"Draw a callgraph using dot in :0 (e.g. svg), and open with xdg-open"