Configurable word size for test signature file output (#136)

2 files changed, 24 insertions, 10 deletions

diff --git a/c_emulator/riscv_sim.c b/c_emulator/riscv_sim.c
index a2d1bce..e908ebb 100644
--- a/c_emulator/riscv_sim.c
+++ b/c_emulator/riscv_sim.c
@@ -68,6 +68,7 @@ size_t spike_dtb_len = 0;
 char *sig_file = NULL;
 uint64_t mem_sig_start = 0;
 uint64_t mem_sig_end = 0;
+int signature_granularity = 4;
 
 bool config_print_instr = true;
 bool config_print_reg = true;
@@ -120,6 +121,7 @@ static struct option options[] = {
   {"show-times",                  required_argument, 0, 'p'},
   {"report-arch",                 no_argument,       0, 'a'},
   {"test-signature",              required_argument, 0, 'T'},
+  {"signature-granularity",       required_argument, 0, 'g'},
 #ifdef RVFI_DII
   {"rvfi-dii",                    required_argument, 0, 'r'},
 #endif
@@ -230,6 +232,7 @@ char *process_args(int argc, char **argv)
                     "b:"
                     "t:"
                     "T:"
+                    "g"
                     "h"
 #ifdef RVFI_DII
                     "r:"
@@ -308,6 +311,10 @@ char *process_args(int argc, char **argv)
       sig_file = strdup(optarg);
       fprintf(stderr, "using %s for test-signature output.\n", sig_file);
       break;
+    case 'g':
+      signature_granularity = atoi(optarg);
+      fprintf(stderr, "setting signature-granularity to %d bytes\n", signature_granularity);
+      break;
     case 'h':
       print_usage(argv[0], 0);
       break;
@@ -578,10 +585,10 @@ void write_signature(const char *file)
     fprintf(stderr, "Cannot open file '%s': %s\n", file, strerror(errno));
     return;
   }
-  /* write out words in signature area */
-  for (uint64_t addr = mem_sig_start; addr < mem_sig_end; addr += 4) {
+  /* write out words depending on signature granularity in signature area */
+  for (uint64_t addr = mem_sig_start; addr < mem_sig_end; addr += signature_granularity) {
     /* most-significant byte first */
-    for (int i = 3; i >= 0; i--) {
+    for (int i = signature_granularity - 1; i >= 0; i--) {
       uint8_t byte = (uint8_t) read_mem(addr+i);
       fprintf(f, "%02x", byte);
     }
diff --git a/ocaml_emulator/riscv_ocaml_sim.ml b/ocaml_emulator/riscv_ocaml_sim.ml
index fb06c40..6e612ad 100644
--- a/ocaml_emulator/riscv_ocaml_sim.ml
+++ b/ocaml_emulator/riscv_ocaml_sim.ml
@@ -11,6 +11,7 @@ let opt_file_arguments = ref ([] : string list)
 let opt_dump_dts = ref false
 let opt_dump_dtb = ref false
 let opt_signature_file = ref (None : string option)
+let signature_granularity_ref = ref 4
 let opt_isa = ref (None : string option)
 
 let report_arch () =
@@ -25,6 +26,9 @@ let set_signature_file s =
   P.config_print_mem_access := false;
   P.config_print_platform := false
 
+let set_signature_granularity sg =
+  signature_granularity_ref := sg
+
 let options = Arg.align ([("-dump-dts",
                            Arg.Set opt_dump_dts,
                            " dump the platform device-tree source to stdout");
@@ -61,6 +65,9 @@ let options = Arg.align ([("-dump-dts",
                           ("-test-signature",
                            Arg.String set_signature_file,
                            " file for signature output (requires ELF signature symbols)");
+                          ("-signature-granularity",
+                           Arg.Int set_signature_granularity,
+                           " test signature granularity (in bytes)");
                           ("-isa",
                            Arg.String (fun s -> opt_isa := Some s),
                            " requested isa");
@@ -109,13 +116,13 @@ let check_elf () =
 let write_bytes fl bytes =
   let i = ref 0 in
   while !i < Bytes.length bytes do
-    let s = Printf.sprintf "%02x%02x%02x%02x\n"
-	(int_of_char (Bytes.get bytes (!i+3)))
-	(int_of_char (Bytes.get bytes (!i+2)))
-	(int_of_char (Bytes.get bytes (!i+1)))
-	(int_of_char (Bytes.get bytes (!i+0))) in
-    output_string fl s;
-    i := !i + 4
+    for j = !signature_granularity_ref - 1 downto 0 do
+      let s = Printf.sprintf "%02x"
+          (int_of_char (Bytes.get bytes (!i + j))) in
+      output_string fl s;
+    done;
+    output_string fl "\n";
+    i := !i + !signature_granularity_ref;
   done
 
 let write_signature f sig_start sig_end =