# ToggleTraceInstructions ## Description Toggle instruction tracing. This command starts instruction tracing. You can then use all the debugger commands as usual: the debugger will save all the modified register values for each instruction. When you click on an instruction trace event in the Tracing window, IDA displays the corresponding register values preceding the execution of this instruction. In the 'Result' column of the Tracing window, you can also see which registers were modified by this instruction. By using this information, you can for example quickly determine which instruction modified a specific register, or you can even backtrace the execution flow. Note that the IP register is never printed in the 'Result' column, although it is usually modified by almost any instruction (except perhaps some prefixed instructions like REP MOVSB, ...). Internally, the debugger runs the current thread step by step to properly obtain all the required register values. This explains why instruction tracing is slower than a normal execution. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.hex-rays.com/ida-actions/toggletraceinstructions.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.