Implement -cheri-trace-format

Fixes #29

qemu-options.hx

@@ -3284,6 +3284,13 @@ STEXI
 @item -bc @var{count}
 Set GDB breakpoint in <count> instructions after start.
 ETEXI
+
+DEF("cheri-trace-format", HAS_ARG, QEMU_OPTION_cheri_trace_format, \
+"-cheri-trace-format [text|cvtrace]     Select CHERI trace mode.\n", QEMU_ARCH_ALL)
+STEXI
+@item -cheri-trace-format @var{type}
+Set CHERI trace format to <type> (text or cvtrace)
+ETEXI
 #endif
 
 

target-mips/op_helper.c

@@ -3523,12 +3523,7 @@ target_ulong helper_cscc_addr(CPUMIPSState *env, uint32_t cs, uint32_t cb)
     return (target_ulong)addr;
 }
 
-#ifdef CHERI_DEFAULT_CVTRACE
-#define CHERI_DEFAULT_TRACE_FLAG CPU_LOG_CVTRACE
-#else
-#define CHERI_DEFAULT_TRACE_FLAG CPU_LOG_INSTR
-#endif
-
+extern int cl_default_trace_format;
 
 #define USER_TRACE_DEBUG 0
 #if USER_TRACE_DEBUG
@@ -3546,10 +3541,10 @@ void helper_instr_start(CPUMIPSState *env, target_ulong pc)
         user_trace_dbg("Delaying tracing request at 0x%lx "
             "until next switch to user mode, ASID %lu\n",
             pc, env->CP0_EntryHi & 0xFF);
-        env->trace_level_before_suspend = CHERI_DEFAULT_TRACE_FLAG;
+        env->trace_level_before_suspend = cl_default_trace_format;
         env->tracing_suspended = true;
     } else {
-        qemu_set_log(qemu_loglevel | CHERI_DEFAULT_TRACE_FLAG);
+        qemu_set_log(qemu_loglevel | cl_default_trace_format);
         user_trace_dbg("Switching on tracing @ 0x%lx ASID %lu\n",
             pc, env->CP0_EntryHi & 0xFF);
         env->tracing_suspended = false;
@@ -3561,7 +3556,7 @@ void helper_instr_stop(CPUMIPSState *env, target_ulong pc)
 {
     user_trace_dbg("Switching off tracing @ 0x%lx ASID %lu\n",
         pc, env->CP0_EntryHi & 0xFF);
-    qemu_set_log(qemu_loglevel & ~CHERI_DEFAULT_TRACE_FLAG);
+    qemu_set_log(qemu_loglevel & ~cl_default_trace_format);
     /* Make sure a kernel -> user switch does not turn on tracing */
     env->trace_level_before_suspend = 0;
     env->tracing_suspended = false;
@@ -3576,8 +3571,8 @@ void helper_instr_start_user_mode_only(CPUMIPSState *env, target_ulong pc)
     env->user_only_tracing_enabled = true;
     /* Disable tracing if we are not currently in user mode */
     if (!IN_USERSPACE(env)) {
-        env->trace_level_before_suspend = qemu_loglevel & CHERI_DEFAULT_TRACE_FLAG;
-        qemu_set_log(qemu_loglevel & ~CHERI_DEFAULT_TRACE_FLAG);
+        env->trace_level_before_suspend = qemu_loglevel & cl_default_trace_format;
+        qemu_set_log(qemu_loglevel & ~cl_default_trace_format);
         env->tracing_suspended = true;
     } else {
         env->tracing_suspended = false;
@@ -3653,7 +3648,7 @@ void helper_cheri_debug_message(struct CPUMIPSState* env, uint64_t pc)
     uint32_t mode = qemu_loglevel & (CPU_LOG_CVTRACE | CPU_LOG_INSTR);
     if (!mode && env->tracing_suspended) {
         /* Always print these messages even if user-space only tracing is on */
-        mode = CHERI_DEFAULT_TRACE_FLAG;
+        mode = cl_default_trace_format;
     }
     if (!mode) {
         return;
@@ -5605,9 +5600,9 @@ static void update_tracing_on_mode_change(CPUMIPSState *env, const char* new_mod
         /* When changing from user mode to kernel mode disable tracing */
         user_trace_dbg("%s -> %s: 0x%lx ASID %lu -- switching off tracing \n",
             env->last_mode, new_mode, env->active_tc.PC, env->CP0_EntryHi & 0xFF);
-        env->trace_level_before_suspend = qemu_loglevel & CHERI_DEFAULT_TRACE_FLAG;
+        env->trace_level_before_suspend = qemu_loglevel & cl_default_trace_format;
         env->tracing_suspended = true;
-        qemu_set_log(qemu_loglevel & ~CHERI_DEFAULT_TRACE_FLAG);
+        qemu_set_log(qemu_loglevel & ~cl_default_trace_format);
     } else if (strcmp(new_mode, TRACE_MODE_USER) == 0) {
         /* When changing back to user mode restore instruction tracing */
         assert(!IN_USERSPACE(env));

target-mips/translate.c

@@ -4583,6 +4583,7 @@ static void gen_logic_imm(DisasContext *ctx, uint32_t opc,
         MIPS_DEBUG("NOP");
 #ifdef TARGET_CHERI
         if (opc == OPC_ORI && rs == 0) {
+        // XXXAR: do we really want this early return in CVTRACE mode?
 #ifndef CHERI_DEFAULT_CVTRACE
 	    /* Don't mix with CheriVis tracing. */
             if (qemu_loglevel_mask(CPU_LOG_CVTRACE))

vl.c

@@ -186,6 +186,14 @@ uint8_t qemu_extra_params_fw[2];
 
 int icount_align_option;
 
+#ifdef CONFIG_CHERI
+#ifdef CHERI_DEFAULT_CVTRACE
+    int cl_default_trace_format = CPU_LOG_CVTRACE;
+#else
+    int cl_default_trace_format = CPU_LOG_INSTR;
+#endif
+#endif
+
 /* The bytes in qemu_uuid[] are in the order specified by RFC4122, _not_ in the
  * little-endian "wire format" described in the SMBIOS 2.6 specification.
  */
@@ -3878,6 +3886,16 @@ int main(int argc, char **argv, char **envp)
             case QEMU_OPTION_breakpoint:
                 cl_breakpoint = strtoull(optarg, NULL, 0);
                 break;
+            case QEMU_OPTION_cheri_trace_format:
+                if (strcmp(optarg, "text") == 0)
+                    cl_default_trace_format = CPU_LOG_INSTR;
+                else if (strcmp(optarg, "cvtrace") == 0)
+                    cl_default_trace_format = CPU_LOG_CVTRACE;
+                else {
+                    printf("Invalid choice for cheri-trace-format: '%s'\n", optarg);
+                    exit(1);
+                }
+                break;
             case QEMU_OPTION_breakcount:
                 cl_breakcount = strtoull(optarg, NULL, 0);
                 break;