diff --git a/lldb/source/Commands/CommandObjectThread.cpp b/lldb/source/Commands/CommandObjectThread.cpp
index e5662dd..bfed4ef 100644
--- a/lldb/source/Commands/CommandObjectThread.cpp
+++ b/lldb/source/Commands/CommandObjectThread.cpp
@@ -161,36 +161,30 @@
 
     ~CommandOptions() override = default;
 
-    Error SetOptionValue(uint32_t option_idx, const char *option_arg,
+    Error SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
                          ExecutionContext *execution_context) override {
       Error error;
       const int short_option = m_getopt_table[option_idx].val;
-      auto option_strref = llvm::StringRef::withNullAsEmpty(option_arg);
 
       switch (short_option) {
       case 'c': {
-        bool success;
-        int32_t input_count =
-            StringConvert::ToSInt32(option_arg, -1, 0, &success);
-        if (!success)
-          error.SetErrorStringWithFormat(
-              "invalid integer value for option '%c'", short_option);
-        if (input_count < -1)
+        int32_t input_count = 0;
+        if (option_arg.getAsInteger(0, m_count)) {
           m_count = UINT32_MAX;
-        else
-          m_count = input_count;
-      } break;
-      case 's': {
-        bool success;
-        m_start = StringConvert::ToUInt32(option_arg, 0, 0, &success);
-        if (!success)
           error.SetErrorStringWithFormat(
               "invalid integer value for option '%c'", short_option);
+        } else if (input_count < 0)
+          m_count = UINT32_MAX;
       } break;
+      case 's':
+        if (option_arg.getAsInteger(0, m_start))
+          error.SetErrorStringWithFormat(
+              "invalid integer value for option '%c'", short_option);
+        break;
       case 'e': {
         bool success;
         m_extended_backtrace =
-            Args::StringToBoolean(option_strref, false, &success);
+            Args::StringToBoolean(option_arg, false, &success);
         if (!success)
           error.SetErrorStringWithFormat(
               "invalid boolean value for option '%c'", short_option);
@@ -335,17 +329,15 @@
 
     ~CommandOptions() override = default;
 
-    Error SetOptionValue(uint32_t option_idx, const char *option_arg,
+    Error SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
                          ExecutionContext *execution_context) override {
       Error error;
       const int short_option = m_getopt_table[option_idx].val;
-      auto option_strref = llvm::StringRef::withNullAsEmpty(option_arg);
 
       switch (short_option) {
       case 'a': {
         bool success;
-        bool avoid_no_debug =
-            Args::StringToBoolean(option_strref, true, &success);
+        bool avoid_no_debug = Args::StringToBoolean(option_arg, true, &success);
         if (!success)
           error.SetErrorStringWithFormat(
               "invalid boolean value for option '%c'", short_option);
@@ -357,8 +349,7 @@
 
       case 'A': {
         bool success;
-        bool avoid_no_debug =
-            Args::StringToBoolean(option_strref, true, &success);
+        bool avoid_no_debug = Args::StringToBoolean(option_arg, true, &success);
         if (!success)
           error.SetErrorStringWithFormat(
               "invalid boolean value for option '%c'", short_option);
@@ -369,9 +360,9 @@
       } break;
 
       case 'c':
-        m_step_count = StringConvert::ToUInt32(option_arg, UINT32_MAX, 0);
-        if (m_step_count == UINT32_MAX)
-          error.SetErrorStringWithFormat("invalid step count '%s'", option_arg);
+        if (option_arg.getAsInteger(0, m_step_count))
+          error.SetErrorStringWithFormat("invalid step count '%s'",
+                                         option_arg.str().c_str());
         break;
 
       case 'C':
@@ -383,23 +374,18 @@
         OptionEnumValueElement *enum_values =
             GetDefinitions()[option_idx].enum_values;
         m_run_mode = (lldb::RunMode)Args::StringToOptionEnum(
-            option_strref, enum_values, eOnlyDuringStepping, error);
+            option_arg, enum_values, eOnlyDuringStepping, error);
       } break;
 
-      case 'e': {
-        if (strcmp(option_arg, "block") == 0) {
+      case 'e':
+        if (option_arg == "block") {
           m_end_line_is_block_end = 1;
           break;
         }
-        uint32_t tmp_end_line =
-            StringConvert::ToUInt32(option_arg, UINT32_MAX, 0);
-        if (tmp_end_line == UINT32_MAX)
+        if (option_arg.getAsInteger(0, m_end_line))
           error.SetErrorStringWithFormat("invalid end line number '%s'",
-                                         option_arg);
-        else
-          m_end_line = tmp_end_line;
+                                         option_arg.str().c_str());
         break;
-      } break;
 
       case 'r':
         m_avoid_regexp.clear();
@@ -921,7 +907,7 @@
 
     ~CommandOptions() override = default;
 
-    Error SetOptionValue(uint32_t option_idx, const char *option_arg,
+    Error SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
                          ExecutionContext *execution_context) override {
       Error error;
       const int short_option = m_getopt_table[option_idx].val;
@@ -934,27 +920,24 @@
           m_until_addrs.push_back(tmp_addr);
       } break;
       case 't':
-        m_thread_idx =
-            StringConvert::ToUInt32(option_arg, LLDB_INVALID_INDEX32);
-        if (m_thread_idx == LLDB_INVALID_INDEX32) {
+        if (option_arg.getAsInteger(0, m_thread_idx)) {
+          m_thread_idx = LLDB_INVALID_INDEX32;
           error.SetErrorStringWithFormat("invalid thread index '%s'",
-                                         option_arg);
+                                         option_arg.str().c_str());
         }
         break;
       case 'f':
-        m_frame_idx =
-            StringConvert::ToUInt32(option_arg, LLDB_INVALID_FRAME_ID);
-        if (m_frame_idx == LLDB_INVALID_FRAME_ID) {
+        if (option_arg.getAsInteger(0, m_frame_idx)) {
+          m_frame_idx = LLDB_INVALID_FRAME_ID;
           error.SetErrorStringWithFormat("invalid frame index '%s'",
-                                         option_arg);
+                                         option_arg.str().c_str());
         }
         break;
       case 'm': {
         OptionEnumValueElement *enum_values =
             GetDefinitions()[option_idx].enum_values;
         lldb::RunMode run_mode = (lldb::RunMode)Args::StringToOptionEnum(
-            llvm::StringRef::withNullAsEmpty(option_arg), enum_values,
-            eOnlyDuringStepping, error);
+            option_arg, enum_values, eOnlyDuringStepping, error);
 
         if (error.Success()) {
           if (run_mode == eAllThreads)
@@ -1339,7 +1322,7 @@
       m_json_stopinfo = false;
     }
 
-    Error SetOptionValue(uint32_t option_idx, const char *option_arg,
+    Error SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
                          ExecutionContext *execution_context) override {
       const int short_option = m_getopt_table[option_idx].val;
       Error error;
@@ -1432,21 +1415,21 @@
 
     ~CommandOptions() override = default;
 
-    Error SetOptionValue(uint32_t option_idx, const char *option_arg,
+    Error SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
                          ExecutionContext *execution_context) override {
       Error error;
       const int short_option = m_getopt_table[option_idx].val;
-      auto option_strref = llvm::StringRef::withNullAsEmpty(option_arg);
 
       switch (short_option) {
       case 'x': {
         bool success;
-        bool tmp_value = Args::StringToBoolean(option_strref, false, &success);
+        bool tmp_value = Args::StringToBoolean(option_arg, false, &success);
         if (success)
           m_from_expression = tmp_value;
         else {
           error.SetErrorStringWithFormat(
-              "invalid boolean value '%s' for 'x' option", option_arg);
+              "invalid boolean value '%s' for 'x' option",
+              option_arg.str().c_str());
         }
       } break;
       default:
@@ -1616,9 +1599,8 @@
       m_force = false;
     }
 
-    Error SetOptionValue(uint32_t option_idx, const char *option_arg,
+    Error SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
                          ExecutionContext *execution_context) override {
-      bool success;
       const int short_option = m_getopt_table[option_idx].val;
       Error error;
 
@@ -1629,14 +1611,12 @@
           return Error("only one source file expected.");
         break;
       case 'l':
-        m_line_num = StringConvert::ToUInt32(option_arg, 0, 0, &success);
-        if (!success || m_line_num == 0)
-          return Error("invalid line number: '%s'.", option_arg);
+        if (option_arg.getAsInteger(0, m_line_num))
+          return Error("invalid line number: '%s'.", option_arg.str().c_str());
         break;
       case 'b':
-        m_line_offset = StringConvert::ToSInt32(option_arg, 0, 0, &success);
-        if (!success)
-          return Error("invalid line offset: '%s'.", option_arg);
+        if (option_arg.getAsInteger(0, m_line_offset))
+          return Error("invalid line offset: '%s'.", option_arg.str().c_str());
         break;
       case 'a':
         m_load_addr = Args::StringToAddress(execution_context, option_arg,
@@ -1764,7 +1744,7 @@
 
     ~CommandOptions() override = default;
 
-    Error SetOptionValue(uint32_t option_idx, const char *option_arg,
+    Error SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
                          ExecutionContext *execution_context) override {
       Error error;
       const int short_option = m_getopt_table[option_idx].val;