Incorporating elf into sequential interpreter

Fix an effect bug on aliased id

1 files changed, 724 insertions, 0 deletions

diff --git a/src/lem_interp/run_with_elf.ml b/src/lem_interp/run_with_elf.ml
new file mode 100644
index 00000000..422f429a
--- /dev/null
+++ b/src/lem_interp/run_with_elf.ml
@@ -0,0 +1,724 @@
+open Printf ;;
+open Big_int ;;
+open Interp_ast ;;
+open Interp_interface ;;
+open Interp_inter_imp ;;
+open Run_interp_model ;;
+
+open Sail_interface ;;
+
+module StringMap = Map.Make(String)
+
+let file = ref "" ;;
+
+let rec foldli f acc ?(i=0) = function
+  | [] -> acc
+  | x::xs -> foldli f (f i acc x) ~i:(i+1) xs
+;;
+
+let endian = ref E_big_endian ;;
+
+let hex_to_big_int s = big_int_of_int64 (Int64.of_string s) ;;
+
+let data_mem = (ref Mem.empty : (memory_byte Run_interp_model.Mem.t) ref) ;;
+let prog_mem = (ref Mem.empty : (memory_byte Run_interp_model.Mem.t) ref) ;;
+let reg = ref Reg.empty ;;
+
+let add_mem byte addr mem =
+  assert(byte >= 0 && byte < 256);
+  (*Printf.printf "adder is %s, byte is %s\n" (string_of_big_int addr) (string_of_int byte);*)
+  let mem_byte = memory_byte_of_int byte in
+  mem := Mem.add addr mem_byte !mem
+
+let get_reg reg name =
+  let reg_content = Reg.find name reg in reg_content
+
+let rec load_memory_segment' (bytes,addr) mem =
+  match bytes with
+  | [] -> ()
+  | byte::bytes' ->
+    let data_byte = Char.code byte in
+    let addr' = Nat_big_num.succ addr in
+    begin add_mem data_byte addr mem;
+      load_memory_segment' (bytes',addr') mem
+    end
+
+let rec load_memory_segment (segment: Elf_interpreted_segment.elf64_interpreted_segment) mem =
+  let (Byte_sequence.Sequence bytes) = segment.Elf_interpreted_segment.elf64_segment_body in
+  let addr = segment.Elf_interpreted_segment.elf64_segment_base in
+  load_memory_segment' (bytes,addr) mem
+
+
+let rec load_memory_segments segments =
+  begin match segments with
+    | [] -> ()
+    | segment::segments' ->
+      let (x,w,r) = segment.Elf_interpreted_segment.elf64_segment_flags in
+      begin
+        (if x
+         then load_memory_segment segment prog_mem
+         else load_memory_segment segment data_mem);
+        load_memory_segments segments'
+      end    
+  end
+  
+let rec read_mem mem address length = 
+  if length = 0  
+  then []
+  else
+    let byte =
+      try Mem.find address mem with
+      | Not_found -> failwith "start address not found"
+    in
+    byte :: (read_mem mem (Nat_big_num.succ address) (length - 1))
+
+let register_state_zero register_data rbn : register_value =
+  let (dir,width,start_index) =
+    try List.assoc rbn register_data with
+    | Not_found -> failwith ("register_state_zero lookup failed (" ^ rbn)
+  in register_value_zeros dir width start_index
+
+type model = PPC | AArch64 | MIPS
+
+let ppc_register_data_all =  [
+  (* special registers *)
+  ("CR",    (D_increasing, 32, 32));
+  ("CTR",   (D_increasing, 64, 0 ));
+  ("LR",    (D_increasing, 64, 0 ));
+  ("XER",   (D_increasing, 64, 0 ));
+  ("VRSAVE",(D_increasing, 32, 32));
+  ("FPSCR", (D_increasing, 64, 0 ));
+  ("VSCR",  (D_increasing, 32, 96));
+
+  (* general purpose registers *)
+  ("GPR0",  (D_increasing, 64, 0 ));
+  ("GPR1",  (D_increasing, 64, 0 ));
+  ("GPR2",  (D_increasing, 64, 0 ));
+  ("GPR3",  (D_increasing, 64, 0 ));
+  ("GPR4",  (D_increasing, 64, 0 ));
+  ("GPR5",  (D_increasing, 64, 0 ));
+  ("GPR6",  (D_increasing, 64, 0 ));
+  ("GPR7",  (D_increasing, 64, 0 ));
+  ("GPR8",  (D_increasing, 64, 0 ));
+  ("GPR9",  (D_increasing, 64, 0 ));
+  ("GPR10", (D_increasing, 64, 0 ));
+  ("GPR11", (D_increasing, 64, 0 ));
+  ("GPR12", (D_increasing, 64, 0 ));
+  ("GPR13", (D_increasing, 64, 0 ));
+  ("GPR14", (D_increasing, 64, 0 ));
+  ("GPR15", (D_increasing, 64, 0 ));
+  ("GPR16", (D_increasing, 64, 0 ));
+  ("GPR17", (D_increasing, 64, 0 ));
+  ("GPR18", (D_increasing, 64, 0 ));
+  ("GPR19", (D_increasing, 64, 0 ));
+  ("GPR20", (D_increasing, 64, 0 ));
+  ("GPR21", (D_increasing, 64, 0 ));
+  ("GPR22", (D_increasing, 64, 0 ));
+  ("GPR23", (D_increasing, 64, 0 ));
+  ("GPR24", (D_increasing, 64, 0 ));
+  ("GPR25", (D_increasing, 64, 0 ));
+  ("GPR26", (D_increasing, 64, 0 ));
+  ("GPR27", (D_increasing, 64, 0 ));
+  ("GPR28", (D_increasing, 64, 0 ));
+  ("GPR29", (D_increasing, 64, 0 ));
+  ("GPR30", (D_increasing, 64, 0 ));
+  ("GPR31", (D_increasing, 64, 0 ));
+  (* vector registers *)
+  ("VR0",  (D_increasing, 128, 0 ));
+  ("VR1",  (D_increasing, 128, 0 ));
+  ("VR2",  (D_increasing, 128, 0 ));
+  ("VR3",  (D_increasing, 128, 0 ));
+  ("VR4",  (D_increasing, 128, 0 ));
+  ("VR5",  (D_increasing, 128, 0 ));
+  ("VR6",  (D_increasing, 128, 0 ));
+  ("VR7",  (D_increasing, 128, 0 ));
+  ("VR8",  (D_increasing, 128, 0 ));
+  ("VR9",  (D_increasing, 128, 0 ));
+  ("VR10", (D_increasing, 128, 0 ));
+  ("VR11", (D_increasing, 128, 0 ));
+  ("VR12", (D_increasing, 128, 0 ));
+  ("VR13", (D_increasing, 128, 0 ));
+  ("VR14", (D_increasing, 128, 0 ));
+  ("VR15", (D_increasing, 128, 0 ));
+  ("VR16", (D_increasing, 128, 0 ));
+  ("VR17", (D_increasing, 128, 0 ));
+  ("VR18", (D_increasing, 128, 0 ));
+  ("VR19", (D_increasing, 128, 0 ));
+  ("VR20", (D_increasing, 128, 0 ));
+  ("VR21", (D_increasing, 128, 0 ));
+  ("VR22", (D_increasing, 128, 0 ));
+  ("VR23", (D_increasing, 128, 0 ));
+  ("VR24", (D_increasing, 128, 0 ));
+  ("VR25", (D_increasing, 128, 0 ));
+  ("VR26", (D_increasing, 128, 0 ));
+  ("VR27", (D_increasing, 128, 0 ));
+  ("VR28", (D_increasing, 128, 0 ));
+  ("VR29", (D_increasing, 128, 0 ));
+  ("VR30", (D_increasing, 128, 0 ));
+  ("VR31", (D_increasing, 128, 0 ));
+  (* floating-point registers *)
+  ("FPR0",  (D_increasing, 64, 0 ));
+  ("FPR1",  (D_increasing, 64, 0 ));
+  ("FPR2",  (D_increasing, 64, 0 ));
+  ("FPR3",  (D_increasing, 64, 0 ));
+  ("FPR4",  (D_increasing, 64, 0 ));
+  ("FPR5",  (D_increasing, 64, 0 ));
+  ("FPR6",  (D_increasing, 64, 0 ));
+  ("FPR7",  (D_increasing, 64, 0 ));
+  ("FPR8",  (D_increasing, 64, 0 ));
+  ("FPR9",  (D_increasing, 64, 0 ));
+  ("FPR10", (D_increasing, 64, 0 ));
+  ("FPR11", (D_increasing, 64, 0 ));
+  ("FPR12", (D_increasing, 64, 0 ));
+  ("FPR13", (D_increasing, 64, 0 ));
+  ("FPR14", (D_increasing, 64, 0 ));
+  ("FPR15", (D_increasing, 64, 0 ));
+  ("FPR16", (D_increasing, 64, 0 ));
+  ("FPR17", (D_increasing, 64, 0 ));
+  ("FPR18", (D_increasing, 64, 0 ));
+  ("FPR19", (D_increasing, 64, 0 ));
+  ("FPR20", (D_increasing, 64, 0 ));
+  ("FPR21", (D_increasing, 64, 0 ));
+  ("FPR22", (D_increasing, 64, 0 ));
+  ("FPR23", (D_increasing, 64, 0 ));
+  ("FPR24", (D_increasing, 64, 0 ));
+  ("FPR25", (D_increasing, 64, 0 ));
+  ("FPR26", (D_increasing, 64, 0 ));
+  ("FPR27", (D_increasing, 64, 0 ));
+  ("FPR28", (D_increasing, 64, 0 ));
+  ("FPR29", (D_increasing, 64, 0 ));
+  ("FPR30", (D_increasing, 64, 0 ));
+  ("FPR31", (D_increasing, 64, 0 ));
+]
+
+let initial_stack_and_reg_data_of_PPC_elf_file e_entry all_data_memory =
+  (* set up initial registers, per 3.4.1 of 64-bit PowerPC ELF Application Binary Interface Supplement 1.9 *)
+
+  let auxiliary_vector_space = Nat_big_num.of_string "17592186042368" (*"0xffffffff800"*) in
+  (* notionally there should be at least an AT_NULL auxiliary vector entry there, but our examples will never read it *)
+
+  (* take start of stack roughly where running gdb on hello5 on bim says it is*)
+  let initial_GPR1_stack_pointer = Nat_big_num.of_string "17592186040320" (*"0xffffffff000"*) in
+  let initial_GPR1_stack_pointer_value =
+    Interp_interface.register_value_of_integer 64 0 Interp_interface.D_increasing initial_GPR1_stack_pointer in
+  (* ELF says we need an initial zero doubleword there *)
+  let initial_stack_data =
+    (* the code actually uses the stack, both above and below, so we map a bit more memory*)
+    (* this is a fairly big but arbitrary chunk *)
+    (* let initial_stack_data_address = Nat_big_num.sub initial_GPR1_stack_pointer (Nat_big_num.of_int 128) in
+        [("initial_stack_data", initial_stack_data_address, Lem_list.replicate (128+32) 0 ))] in *)
+    (* this is the stack memory that test 1938 actually uses *)
+    [ ("initial_stack_data1", Nat_big_num.sub initial_GPR1_stack_pointer (Nat_big_num.of_int 128),
+       Lem_list.replicate 8 0 );
+      ("initial_stack_data2", Nat_big_num.sub initial_GPR1_stack_pointer (Nat_big_num.of_int 8),
+       Lem_list.replicate 8  0 );
+      ("initial_stack_data3", Nat_big_num.add initial_GPR1_stack_pointer (Nat_big_num.of_int 16),
+       Lem_list.replicate 8  0 )] in
+  
+  (* read TOC from the second field of the function descriptor pointed to by e_entry*)
+  let initial_GPR2_TOC =
+    Interp_interface.register_value_of_address
+      (Interp_interface.address_of_byte_list
+         (List.map (fun b -> match b with Some b -> b | None -> failwith "Address had undefined")
+             (List.map byte_of_byte_lifted
+                (read_mem all_data_memory
+                   (Nat_big_num.add (Nat_big_num.of_int 8) e_entry) 8))))
+      Interp_interface.D_increasing in
+  (* these initial register values are all mandated to be zero, but that's handled by the generic zeroing below
+      let initial_GPR3_argc = (Nat_big_num.of_int 0) in
+      let initial_GPR4_argv = (Nat_big_num.of_int 0) in
+      let initial_GPR5_envp = (Nat_big_num.of_int 0) in
+      let initial_FPSCR = (Nat_big_num.of_int 0) in
+  *)
+  let initial_register_abi_data : (string * Interp_interface.register_value) list =
+    [ ("GPR1", initial_GPR1_stack_pointer_value);
+      ("GPR2", initial_GPR2_TOC);
+  (*
+    ("GPR3", initial_GPR3_argc);
+    ("GPR4", initial_GPR4_argv);
+    ("GPR5", initial_GPR5_envp);
+    ("FPSCR", initial_FPSCR);
+    *)
+    ] in
+
+  (initial_stack_data, initial_register_abi_data)
+
+
+let aarch64_reg bit_count name = (name, (D_decreasing, bit_count, bit_count - 1))
+
+let aarch64_PC_data = [aarch64_reg 64 "_PC"]
+
+(* most of the PSTATE fields are aliases to other registers so they
+   don't appear here *)
+let aarch64_PSTATE_data  = [
+  aarch64_reg 1 "PSTATE_nRW";
+  aarch64_reg 1 "PSTATE_E";
+  aarch64_reg 5 "PSTATE_M";
+]
+
+let aarch64_general_purpose_registers_data = [
+  aarch64_reg 64 "R0";
+  aarch64_reg 64 "R1";
+  aarch64_reg 64 "R2";
+  aarch64_reg 64 "R3";
+  aarch64_reg 64 "R4";
+  aarch64_reg 64 "R5";
+  aarch64_reg 64 "R6";
+  aarch64_reg 64 "R7";
+  aarch64_reg 64 "R8";
+  aarch64_reg 64 "R9";
+  aarch64_reg 64 "R10";
+  aarch64_reg 64 "R11";
+  aarch64_reg 64 "R12";
+  aarch64_reg 64 "R13";
+  aarch64_reg 64 "R14";
+  aarch64_reg 64 "R15";
+  aarch64_reg 64 "R16";
+  aarch64_reg 64 "R17";
+  aarch64_reg 64 "R18";
+  aarch64_reg 64 "R19";
+  aarch64_reg 64 "R20";
+  aarch64_reg 64 "R21";
+  aarch64_reg 64 "R22";
+  aarch64_reg 64 "R23";
+  aarch64_reg 64 "R24";
+  aarch64_reg 64 "R25";
+  aarch64_reg 64 "R26";
+  aarch64_reg 64 "R27";
+  aarch64_reg 64 "R28";
+  aarch64_reg 64 "R29";
+  aarch64_reg 64 "R30";
+]
+
+let aarch64_SIMD_registers_data = [
+  aarch64_reg 128 "V0";
+  aarch64_reg 128 "V1";
+  aarch64_reg 128 "V2";
+  aarch64_reg 128 "V3";
+  aarch64_reg 128 "V4";
+  aarch64_reg 128 "V5";
+  aarch64_reg 128 "V6";
+  aarch64_reg 128 "V7";
+  aarch64_reg 128 "V8";
+  aarch64_reg 128 "V9";
+  aarch64_reg 128 "V10";
+  aarch64_reg 128 "V11";
+  aarch64_reg 128 "V12";
+  aarch64_reg 128 "V13";
+  aarch64_reg 128 "V14";
+  aarch64_reg 128 "V15";
+  aarch64_reg 128 "V16";
+  aarch64_reg 128 "V17";
+  aarch64_reg 128 "V18";
+  aarch64_reg 128 "V19";
+  aarch64_reg 128 "V20";
+  aarch64_reg 128 "V21";
+  aarch64_reg 128 "V22";
+  aarch64_reg 128 "V23";
+  aarch64_reg 128 "V24";
+  aarch64_reg 128 "V25";
+  aarch64_reg 128 "V26";
+  aarch64_reg 128 "V27";
+  aarch64_reg 128 "V28";
+  aarch64_reg 128 "V29";
+  aarch64_reg 128 "V30";
+  aarch64_reg 128 "V31";
+]
+
+let aarch64_special_purpose_registers_data = [
+  aarch64_reg 32 "CurrentEL";
+  aarch64_reg 32 "DAIF";
+  aarch64_reg 32 "NZCV";
+  aarch64_reg 64 "SP_EL0";
+  aarch64_reg 64 "SP_EL1";
+  aarch64_reg 64 "SP_EL2";
+  aarch64_reg 64 "SP_EL3";
+  aarch64_reg 32 "SPSel";
+  aarch64_reg 32 "SPSR_EL1";
+  aarch64_reg 32 "SPSR_EL2";
+  aarch64_reg 32 "SPSR_EL3";
+  aarch64_reg 64 "ELR_EL1";
+  aarch64_reg 64 "ELR_EL2";
+  aarch64_reg 64 "ELR_EL3";
+]
+
+let aarch64_general_system_control_registers_data = [
+  aarch64_reg 64 "HCR_EL2";
+  aarch64_reg 64 "ID_AA64MMFR0_EL1";
+  aarch64_reg 64 "RVBAR_EL1";
+  aarch64_reg 64 "RVBAR_EL2";
+  aarch64_reg 64 "RVBAR_EL3";
+  aarch64_reg 32 "SCR_EL3";
+  aarch64_reg 32 "SCTLR_EL1";
+  aarch64_reg 32 "SCTLR_EL2";
+  aarch64_reg 32 "SCTLR_EL3";
+  aarch64_reg 64 "TCR_EL1";
+  aarch64_reg 32 "TCR_EL2";
+  aarch64_reg 32 "TCR_EL3";
+]
+
+let aarch64_debug_registers_data = [
+  aarch64_reg 32 "DBGPRCR_EL1";
+  aarch64_reg 32 "OSDLR_EL1";
+]
+
+let aarch64_performance_monitors_registers_data = []
+let aarch64_generic_timer_registers_data = []
+let aarch64_generic_interrupt_controller_CPU_interface_registers_data = []
+
+let aarch64_external_debug_registers_data = [
+  aarch64_reg 32 "EDSCR";
+]
+
+let aarch32_general_system_control_registers_data = [
+  aarch64_reg 32 "SCR";
+]
+
+let aarch32_debug_registers_data = [
+  aarch64_reg 32 "DBGOSDLR";
+  aarch64_reg 32 "DBGPRCR";
+]
+
+let aarch64_register_data_all =
+  aarch64_PC_data @
+  aarch64_PSTATE_data @
+  aarch64_general_purpose_registers_data @
+  aarch64_SIMD_registers_data @
+  aarch64_special_purpose_registers_data @
+  aarch64_general_system_control_registers_data @
+  aarch64_debug_registers_data @
+  aarch64_performance_monitors_registers_data @
+  aarch64_generic_timer_registers_data @
+  aarch64_generic_interrupt_controller_CPU_interface_registers_data @
+  aarch64_external_debug_registers_data @
+  aarch32_general_system_control_registers_data @
+  aarch32_debug_registers_data
+
+let initial_stack_and_reg_data_of_AAarch64_elf_file e_entry all_data_memory =
+  let (reg_SP_EL0_direction, reg_SP_EL0_width, reg_SP_EL0_initial_index) =
+    List.assoc "SP_EL0" aarch64_register_data_all in
+  
+  (* we compiled a small program that prints out SP and run it a few
+      times on the Nexus9, these are the results:
+      0x0000007fe7f903e0
+      0x0000007fdcdbf3f0
+      0x0000007fcbe1ba90
+      0x0000007fcf378280
+      0x0000007fdd54b8d0
+      0x0000007fd961bc10
+      0x0000007ff3be6350
+      0x0000007fd6bf6ef0
+      0x0000007fff7676f0
+      0x0000007ff2c34560 *)
+  let initial_SP_EL0 = Nat_big_num.of_string "549739036672" (*"0x0000007fff000000"*) in
+  let initial_SP_EL0_value =
+    Interp_interface.register_value_of_integer
+      reg_SP_EL0_width
+      reg_SP_EL0_initial_index
+      reg_SP_EL0_direction
+      initial_SP_EL0
+  in
+
+  (* ELF says we need an initial zero doubleword there *)
+  (* the code actually uses the stack, both above and below, so we map a bit more memory*)
+  let initial_stack_data =
+    (* this is a fairly big but arbitrary chunk: *)
+    (* let initial_stack_data_address = Nat_big_num.sub initial_GPR1_stack_pointer (Nat_big_num.of_int 128) in
+        [("initial_stack_data", initial_stack_data_address, Lem_list.replicate (128+32) 0 ))] in *)
+    
+    [ ("initial_stack_data1", Nat_big_num.sub initial_SP_EL0 (Nat_big_num.of_int 16),  Lem_list.replicate 8 0);
+      ("initial_stack_data2", Nat_big_num.sub initial_SP_EL0 (Nat_big_num.of_int 8),   Lem_list.replicate 8 0)
+    ]
+  in
+
+  let initial_register_abi_data : (string * Interp_interface.register_value) list =
+    [("SP_EL0", initial_SP_EL0_value)]
+  in
+
+  (initial_stack_data, initial_register_abi_data)
+
+
+let initial_system_state_of_elf_file name = 
+
+  (* call ELF analyser on file *)
+  match Sail_interface.populate_and_obtain_global_symbol_init_info name with
+  | Error.Fail s -> failwith ("populate_and_obtain_global_symbol_init_info: " ^ s)
+  | Error.Success 
+      ((elf_epi: Sail_interface.executable_process_image),
+       (symbol_map: Elf_file.global_symbol_init_info))
+    ->
+    let (segments, e_entry, e_machine) =
+      begin match elf_epi with
+        | ELF_Class_32 _ -> failwith "cannot handle ELF_Class_32"
+        | ELF_Class_64 (segments,e_entry,e_machine) ->
+          (* remove all the auto generated segments (they contain only 0s) *)
+          let segments =
+            Lem_list.mapMaybe
+              (fun (seg, prov) -> if prov = Elf_file.FromELF then Some seg else None)
+              segments
+          in
+          (segments,e_entry,e_machine)
+      end
+    in
+
+    (* construct program memory and start address *)
+    begin
+      prog_mem := Mem.empty;
+      data_mem := Mem.empty;
+      load_memory_segments segments;
+
+      let (isa_defs, isa_memory_access, isa_externs, startaddr,
+           initial_stack_data, initial_register_abi_data, register_data_all) =
+        match Nat_big_num.to_int e_machine with
+        | 21  (* EM_PPC64 *) ->
+          let startaddr =
+            let e_entry = Uint64.of_int64 (Nat_big_num.to_int64 e_entry) in
+            match Abi_power64.abi_power64_compute_program_entry_point segments e_entry with
+            | Error.Fail s -> failwith "Failed computing entry point"
+            | Error.Success s -> Nat_big_num.of_int64 (Uint64.to_int64 s)
+          in
+          let (initial_stack_data, initial_register_abi_data) =
+            initial_stack_and_reg_data_of_PPC_elf_file e_entry !data_mem in
+
+            (Power.defs,
+              (Power_extras.read_memory_functions,Power_extras.memory_writes,[],[],Power_extras.barrier_functions),
+              Power_extras.power_externs,
+              startaddr,
+              initial_stack_data,
+              initial_register_abi_data,
+              ppc_register_data_all)
+
+        | 183 (* EM_AARCH64 *) ->
+            let startaddr =
+              let e_entry = Uint64.of_int64 (Nat_big_num.to_int64 e_entry) in
+              match Abi_aarch64_le.abi_aarch64_le_compute_program_entry_point segments e_entry with
+                | Error.Fail s -> failwith "Failed computing entry point"
+                | Error.Success s -> Nat_big_num.of_int64 (Uint64.to_int64 s)
+            in
+
+            let (initial_stack_data, initial_register_abi_data) =
+              initial_stack_and_reg_data_of_AAarch64_elf_file e_entry !data_mem in
+            
+            (ArmV8.defs,
+             (ArmV8_extras.aArch64_read_memory_functions,
+              ArmV8_extras.aArch64_memory_writes,
+	      ArmV8_extras.aArch64_memory_eas,
+	      ArmV8_extras.aArch64_memory_vals,
+              ArmV8_extras.aArch64_barrier_functions),
+             [],
+             startaddr,
+             initial_stack_data,
+             initial_register_abi_data,
+             aarch64_register_data_all)
+
+        | _ -> failwith (Printf.sprintf "Sail sequential interpreter can't handle the e_machine value %s, only EM_PPC64 and EM_AARCH64 are supported." (Nat_big_num.to_string e_machine))
+      in
+      
+      (* pull the object symbols from the symbol table *)
+      let symbol_table : (string * Nat_big_num.num * int * word8 list (*their bytes*)) list =
+        let rec convert_symbol_table symbol_map =
+          begin match symbol_map with
+          | [] -> []
+          | ((name: string),
+             ((typ: Nat_big_num.num),
+              (size: Nat_big_num.num (*number of bytes*)),
+              (address: Nat_big_num.num),
+              (mb: Byte_sequence.byte_sequence option (*present iff type=stt_object*)),
+              (binding: Nat_big_num.num)))
+	    (*              (mb: Byte_sequence_wrapper.t option (*present iff type=stt_object*)) )) *)
+            ::symbol_map' ->
+            if Nat_big_num.equal typ Elf_symbol_table.stt_object && not (Nat_big_num.equal size (Nat_big_num.of_int 0))
+            then
+              (
+                (* an object symbol - map *)
+                (*Printf.printf "*** size %d ***\n" (Nat_big_num.to_int size);*)
+                let bytes =
+                  (match mb with
+                   | None -> raise (Failure "this cannot happen")
+                   | Some (Sequence bytes) ->
+                     List.map (fun (c:char) -> Char.code c) bytes) in
+                 (name, address, List.length bytes, bytes):: convert_symbol_table symbol_map'
+              )
+              else
+                (* not an object symbol or of zero size - ignore *)
+                convert_symbol_table symbol_map'
+          end
+        in
+        (List.map (fun (n,a,bs) -> (n,a,List.length bs,bs)) initial_stack_data) @ convert_symbol_table symbol_map
+      in
+
+      (* invert the symbol table to use for pp *)
+      let symbol_table_pp : ((Interp_interface.address * int) * string) list =
+        (* map symbol to (bindings, footprint),
+           if a symbol appears more then onece keep the one with higher
+           precedence (stb_global > stb_weak > stb_local) *)
+        let map =
+          List.fold_left
+            (fun map (name, (typ, size, address, mb, binding)) ->
+               if String.length name <> 0 &&
+                  (if String.length name = 1 then Char.code (String.get name 0) <> 0 else true) &&
+                  not (Nat_big_num.equal address (Nat_big_num.of_int 0))
+               then
+                 try
+                   let (binding', _) = StringMap.find name map in
+                   if  Nat_big_num.equal binding' Elf_symbol_table.stb_local ||
+                       Nat_big_num.equal binding Elf_symbol_table.stb_global
+                   then
+                     StringMap.add name (binding,
+                                         (Interp_interface.address_of_integer address, Nat_big_num.to_int size)) map
+                   else map
+                 with Not_found ->
+                   StringMap.add name (binding,
+                                       (Interp_interface.address_of_integer address, Nat_big_num.to_int size)) map
+                     
+               else map
+            )
+            StringMap.empty
+            symbol_map
+        in
+
+        List.map (fun (name, (binding, fp)) -> (fp, name)) (StringMap.bindings map)
+      in
+
+
+      (* Now we examine the rest of the data memory,
+         removing the footprint of the symbols and chunking it into aligned chunks *)
+      
+      let rec remove_symbols_from_data_memory data_mem symbols =
+        match symbols with
+        | [] -> data_mem
+        | (name,address,size,bs)::symbols' ->
+          let data_mem' =
+            Mem.filter
+              (fun a v ->
+                 not (Nat_big_num.greater_equal a address &&
+                      Nat_big_num.less a (Nat_big_num.add (Nat_big_num.of_int (List.length bs)) address)))
+              data_mem in
+          remove_symbols_from_data_memory data_mem' symbols' in
+
+      let trimmed_data_memory : (Nat_big_num.num * memory_byte) list =
+        Mem.bindings (remove_symbols_from_data_memory !data_mem symbol_table) in
+
+      (* make sure that's ordered increasingly.... *)
+      let trimmed_data_memory =
+        List.sort (fun (a,b) (a',b') -> Nat_big_num.compare a a') trimmed_data_memory in
+
+      let aligned a n =  (* a mod n = 0 *)
+        let n_big = Nat_big_num.of_int n in
+        Nat_big_num.equal (Nat_big_num.modulus a n_big) ((Nat_big_num.of_int 0)) in
+
+      let isplus a' a n =   (* a' = a+n *)
+        Nat_big_num.equal a' (Nat_big_num.add (Nat_big_num.of_int n) a) in
+
+      let rec chunk_data_memory dm =
+        match dm with
+        | (a0,b0)::(a1,b1)::(a2,b2)::(a3,b3)::(a4,b4)::(a5,b5)::(a6,b6)::(a7,b7)::dm'  when
+            (aligned a0 8 && isplus a1 a0 1 && isplus a2 a0 2 && isplus a3 a0 3 &&
+             isplus a4 a0 4 && isplus a5 a0 5 && isplus a6 a0 6 && isplus a7 a0 7) ->
+          (a0,8,[b0;b1;b2;b3;b4;b5;b6;b7]) :: chunk_data_memory dm'
+        | (a0,b0)::(a1,b1)::(a2,b2)::(a3,b3)::dm' when
+            (aligned a0 4 && isplus a1 a0 1 && isplus a2 a0 2 && isplus a3 a0 3) ->
+              (a0,4,[b0;b1;b2;b3]) :: chunk_data_memory dm'
+        | (a0,b0)::(a1,b1)::dm' when
+            (aligned a0 2 && isplus a1 a0 1) ->
+              (a0,2,[b0;b1]) :: chunk_data_memory dm'
+        | (a0,b0)::dm' ->
+            (a0,1,[b0]):: chunk_data_memory dm'
+        | [] -> [] in
+
+      let initial_register_state =
+        fun rbn ->
+          try
+            List.assoc rbn initial_register_abi_data
+          with
+            Not_found ->
+              (register_state_zero register_data_all) rbn
+      in
+
+      (* construct initial system state *)
+      let initial_system_state =
+        (isa_defs,
+	  isa_memory_access,
+	  isa_externs,
+          register_data_all,
+          initial_register_state,
+          (Interp_interface.address_of_integer startaddr))
+      in
+
+      (initial_system_state, symbol_table_pp)
+
+    end
+
+let eager_eval = ref true
+
+let args = [
+  ("--file", Arg.Set_string file, "filename binary code to load in memory");
+  ("--quiet", Arg.Clear Run_interp_model.debug, "do not display interpreter actions");
+  ("--interactive", Arg.Clear eager_eval , "interactive execution");
+]
+
+let time_it action arg =
+  let start_time = Sys.time () in
+  ignore (action arg);
+  let finish_time = Sys.time () in
+  finish_time -. start_time
+;;
+
+let eq_zero = function
+  | Bitvector(bools,_,_) -> List.for_all (not) bools
+;;
+
+let rec fde_loop count main_func parameters mem reg ?mode track_dependencies prog =
+  debugf "\n**** instruction %d  ****\n" count;
+  match Run_interp_model.run ~main_func ~parameters ~mem ~reg ~eager_eval:!eager_eval ~track_dependencies:(ref track_dependencies) ?mode prog with
+  | false, _,_, _ -> eprintf "FAILURE\n"; exit 1
+  | true, mode, track_dependencies, (my_reg, my_mem) ->
+      if eq_zero (get_reg my_reg "CIA") then
+        (if not(!test_format) 
+	 then eprintf "\nSUCCESS: returned with value %s\n"
+          (Printing_functions.val_to_string (get_reg my_reg "GPR3"))
+	 else print_test_results my_reg my_mem)	    
+      else
+        fde_loop (count+1) main_func parameters my_mem my_reg ~mode:mode track_dependencies prog
+;;
+
+let run () =
+  Arg.parse args (fun _ -> raise (Arg.Bad "anonymous parameter")) "" ;
+  if !file = "" then begin
+    Arg.usage args "";
+    exit 1;
+  end;
+  if !eager_eval then Run_interp_model.debug := true;
+
+  let (((locations,start_address),_),(symbol_map)) = populate_and_obtain_symbol_to_address_mapping !file in
+  let total_size = (List.length locations) in
+
+  let t = time_it (List.iter load_memory) locations in
+
+  let addr = read_mem !mem (big_int_of_int start_address) 8 in
+  let _ = begin
+    startaddr := addr;
+    mainaddr := "0x" ^ (List.fold_left (^) "" (List.map (Printf.sprintf "%02x") addr));
+  end in
+  if not(!test_format) then
+    Printf.printf "start address: %s\n" !mainaddr;
+  let my_reg = init_reg () in
+  reg := my_reg;
+  if !test_format 
+  then if List.mem_assoc "TEST_MEM" symbol_map
+    then test_memory_addr := 
+      let num = (List.assoc "TEST_MEM" symbol_map) in
+      match big_int_to_vec true (big_int_of_int num) (big_int_of_int 64) with
+	| Bytevector location -> (num,location);
+    else ();
+  (* entry point: unit -> unit fde *)
+  let funk_name = "fde" in
+  let parms = [] in
+  let name = Filename.basename !file in
+  if !print_bytes 
+  then lem_print_memory !mem
+  else let t =time_it (fun () -> fde_loop 0 funk_name parms !mem !reg false (name, Power.defs)) () in
+       if not(!test_format) then eprintf "Execution time: %f seconds\n" t
+;;
+
+run () ;;