[trace][intelpt] fix some test failures

Minor fixes needed and now `./bin/lldb-dotest -p TestTrace` passes
correctly.

- There was an incorrect iteration.
- Some error messages changed.
- The way repeat commands are handled changed a bit, so I had to create
a new --continue arg in "thread trace dump instructions" to handle this
correctly.

Differential Revision: https://reviews.llvm.org/D122023

lldb/source/Commands/CommandObjectThread.cpp

@@ -2032,7 +2032,7 @@ public:
 
     unsigned i = 0;
     for (llvm::StringRef plugin_name =
-             PluginManager::GetTraceExporterPluginNameAtIndex(i++);
+             PluginManager::GetTraceExporterPluginNameAtIndex(i);
          !plugin_name.empty();
          plugin_name = PluginManager::GetTraceExporterPluginNameAtIndex(i++)) {
       if (ThreadTraceExportCommandCreator command_creator =
@@ -2147,6 +2147,10 @@ public:
         m_show_tsc = true;
         break;
       }
+      case 'C': {
+        m_continue = true;
+        break;
+      }
       default:
         llvm_unreachable("Unimplemented option");
       }
@@ -2159,6 +2163,7 @@ public:
       m_raw = false;
       m_forwards = false;
       m_show_tsc = false;
+      m_continue = false;
     }
 
     llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
@@ -2173,6 +2178,7 @@ public:
     bool m_raw;
     bool m_forwards;
     bool m_show_tsc;
+    bool m_continue;
   };
 
   CommandObjectTraceDumpInstructions(CommandInterpreter &interpreter)
@@ -2192,24 +2198,19 @@ public:
 
   llvm::Optional<std::string> GetRepeatCommand(Args &current_command_args,
                                                uint32_t index) override {
-    current_command_args.GetCommandString(m_repeat_command);
-    m_create_repeat_command_just_invoked = true;
-    return m_repeat_command;
+    std::string cmd;
+    current_command_args.GetCommandString(cmd);
+    if (cmd.find("--continue") == std::string::npos)
+      cmd += " --continue";
+    return cmd;
   }
 
 protected:
   bool DoExecute(Args &args, CommandReturnObject &result) override {
-    if (!IsRepeatCommand())
+    if (!m_options.m_continue)
       m_dumpers.clear();
 
-    bool status = CommandObjectIterateOverThreads::DoExecute(args, result);
-
-    m_create_repeat_command_just_invoked = false;
-    return status;
-  }
-
-  bool IsRepeatCommand() {
-    return !m_repeat_command.empty() && !m_create_repeat_command_just_invoked;
+    return CommandObjectIterateOverThreads::DoExecute(args, result);
   }
 
   bool HandleOneThread(lldb::tid_t tid, CommandReturnObject &result) override {
@@ -2249,10 +2250,6 @@ protected:
   }
 
   CommandOptions m_options;
-
-  // Repeat command helpers
-  std::string m_repeat_command;
-  bool m_create_repeat_command_just_invoked = false;
   std::map<lldb::tid_t, std::unique_ptr<TraceInstructionDumper>> m_dumpers;
 };
 

lldb/source/Commands/Options.td

@@ -1116,6 +1116,12 @@ let Command = "thread trace dump instructions" in {
   def thread_trace_dump_instructions_show_tsc : Option<"tsc", "t">,
     Group<1>,
     Desc<"For each instruction, print the corresponding timestamp counter if available.">;
+  def thread_trace_dump_instructions_continue: Option<"continue", "C">,
+    Group<1>,
+    Desc<"Continue dumping instructions right where the previous invocation of this "
+    "command was left, or from the beginning if this is the first invocation. The --skip "
+    "argument is discarded and the other arguments are preserved from the previous "
+    "invocation when possible.">;
 }
 
 let Command = "thread trace dump info" in {

lldb/test/API/commands/trace/TestTraceDumpInfo.py

@@ -18,7 +18,7 @@ class TestTraceDumpInfo(TraceIntelPTTestCaseBase):
             os.path.join(self.getSourceDir(), "intelpt-trace", "a.out"))
 
         self.expect("thread trace dump info",
-            substrs=["error: invalid process"],
+            substrs=["error: Command requires a current process."],
             error=True)
 
         # Now we check the output when there's a running target without a trace

lldb/test/API/commands/trace/TestTraceDumpInstructions.py

@@ -19,7 +19,7 @@ class TestTraceDumpInstructions(TraceIntelPTTestCaseBase):
             os.path.join(self.getSourceDir(), "intelpt-trace", "a.out"))
 
         self.expect("thread trace dump instructions",
-            substrs=["error: invalid process"],
+            substrs=["error: Command requires a current process."],
             error=True)
 
         # Now we check the output when there's a running target without a trace

lldb/test/API/commands/trace/TestTraceExport.py

@@ -23,7 +23,7 @@ class TestTraceExport(TraceIntelPTTestCaseBase):
             os.path.join(self.getSourceDir(), "intelpt-trace", "a.out"))
 
         self.expect(f"thread trace export ctf --file {ctf_test_file}",
-            substrs=["error: invalid process"],
+            substrs=["error: Command requires a current process."],
             error=True)
 
         # Now we check the output when there's a running target without a trace
@@ -172,4 +172,3 @@ class TestTraceExport(TraceIntelPTTestCaseBase):
         data_index = index_of_first_layer_1_block
         for i in range(len(expected_block_names)):
             self.assertTrue(data[data_index + i]['name'] == expected_block_names[i])
-

lldb/test/API/commands/trace/TestTraceSave.py

@@ -18,7 +18,7 @@ class TestTraceSave(TraceIntelPTTestCaseBase):
             os.path.join(self.getSourceDir(), "intelpt-trace", "a.out"))
 
         self.expect("process trace save",
-            substrs=["error: invalid process"],
+            substrs=["error: Command requires a current process."],
             error=True)
 
         # Now we check the output when there's a running target without a trace