Various improvements to menhir parser, and performance improvments for Z3 calls

New option -memo_z3 memoizes calls to the Z3 solver, and saves these
results between calls to sail. This greatly increases the performance
of sail when re-checking large specifications by about an order of
magnitude. For example:

time sail -no_effects prelude.sail aarch64_no_vector.sail

real	0m4.391s
user	0m0.856s
sys	0m0.464s

After running with -memo_z3 once, running again gives:

time sail -memo_z3 -no_effects prelude.sail aarch64_no_vector.sail

real	0m0.457s
user	0m0.448s
sys	0m0.008s

Both the old and the new parser should now have better error messages
where the location of the parse error is displayed visually in the
error message and highlighted.

1 files changed, 10 insertions, 8 deletions

diff --git a/src/reporting_basic.ml b/src/reporting_basic.ml
index e552dca4..a47ee8ae 100644
--- a/src/reporting_basic.ml
+++ b/src/reporting_basic.ml
@@ -87,14 +87,6 @@
 (*  IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.                         *)
 (**************************************************************************)
 
-let format_pos ff p =
-  let open Lexing in
-  begin
-    Format.fprintf ff "file \"%s\", line %d, character %d:\n"
-                   p.pos_fname p.pos_lnum (p.pos_cnum - p.pos_bol);
-    Format.pp_print_flush ff ()
-  end
-
 let rec skip_lines in_chan = function
   | n when n <= 0 -> ()
   | n -> input_line in_chan; skip_lines in_chan (n - 1)
@@ -126,6 +118,16 @@ let print_code1 ff fname lnum1 cnum1 cnum2 =
     end
   with _ -> ()
 
+let format_pos ff p =
+  let open Lexing in
+  begin
+    Format.fprintf ff "file \"%s\", line %d, character %d:\n\n"
+                   p.pos_fname p.pos_lnum (p.pos_cnum - p.pos_bol);
+    print_code1 ff p.pos_fname p.pos_lnum (p.pos_cnum - p.pos_bol) (p.pos_cnum - p.pos_bol + 1);
+    Format.fprintf ff "\n\n";
+    Format.pp_print_flush ff ()
+  end
+
 let print_code2 ff fname lnum1 cnum1 lnum2 cnum2 =
   try
     let in_chan = open_in fname in