Revert "Add a faster vector indexing function that doesn't use GMP"

This reverts commit 0353519.

Author: Alasdair

src/sail_c_backend/c_backend.ml

@@ -483,15 +483,6 @@ end) : CONFIG = struct
         | _ -> no_change
       end
     | "vector_access", [AV_cval (vec, _); AV_cval (n, _)] -> AE_val (AV_cval (V_call (Bvaccess, [vec; n]), typ))
-    | "vector_access", [v; AV_cval (n, _)] -> (
-        match destruct_vector ctx.tc_env (aval_typ v) with
-        | Some _ -> (
-            match cval_ctyp n with
-            | CT_fint 64 -> AE_app (Pure_extern (mk_id "fast_vector_access"), args, typ)
-            | _ -> no_change
-          )
-        | None -> no_change
-      )
     | "add_int", [AV_cval (op1, _); AV_cval (op2, _)] -> begin
         match destruct_range ctx.local_env typ with
         | None -> no_change
@@ -1452,11 +1443,6 @@ module Codegen (Config : CODEGEN_CONFIG) = struct
               | cval :: _ -> sprintf "vector_access_%s" (sgen_ctyp_name (cval_ctyp cval))
               | _ -> c_error "vector access function with bad arity."
             end
-          | "fast_vector_access", _ -> begin
-              match args with
-              | cval :: _ -> sprintf "fast_vector_access_%s" (sgen_ctyp_name (cval_ctyp cval))
-              | _ -> c_error "vector access function with bad arity."
-            end
           | "vector_init", _ -> sprintf "vector_init_%s" (sgen_ctyp_name ctyp)
           | "vector_update_subrange", _ -> sprintf "vector_update_subrange_%s" (sgen_ctyp_name ctyp)
           | "vector_update_subrange_inc", _ -> sprintf "vector_update_subrange_inc_%s" (sgen_ctyp_name ctyp)
@@ -2061,19 +2047,6 @@ module Codegen (Config : CODEGEN_CONFIG) = struct
             (ksprintf string "vector_access_%s(%s *rop, %s op, sail_int n)" (sgen_id id) (sgen_ctyp ctyp) (sgen_id id))
             [c_stmt "int m = sail_int_get_ui(n)"; sail_copy ~suffix:";" (sgen_ctyp_name ctyp) "rop, op.data[m]"]
       in
-      let fast_vector_access =
-        if is_stack_ctyp ctx ctyp then
-          c_function
-            ~return:("static " ^ sgen_ctyp ctyp)
-            (ksprintf string "fast_vector_access_%s(%s op, int64_t n)" (sgen_id id) (sgen_id id))
-            [c_stmt "return op.data[n]"]
-        else
-          c_function ~return:"static void"
-            (ksprintf string "fast_vector_access_%s(%s *rop, %s op, int64_t n)" (sgen_id id) (sgen_ctyp ctyp)
-               (sgen_id id)
-            )
-            [sail_copy ~suffix:";" (sgen_ctyp_name ctyp) "rop, op.data[n]"]
-      in
       let internal_vector_init =
         c_function ~return:"static void"
           (ksprintf string "internal_vector_init_%s(%s *rop, const int64_t len)" (sgen_id id) (sgen_id id))
@@ -2132,7 +2105,6 @@ module Codegen (Config : CODEGEN_CONFIG) = struct
           Impl vector_reinit;
           Impl vector_undefined;
           Impl vector_access;
-          Impl fast_vector_access;
           Impl vector_set;
           Impl vector_update;
           Impl vector_equal;