Examine the captured trace in the Trace tab:
Observe that within a trace range:
Called functions are not traced, only the calls to functions.
There are many discontinuities, which are identified by the message
Warning: Trace Pause. This shows where instruction executions or data accesses occur, but are not captured because of the current trace conditions.
Display the source analysis view for the captured trace:
Click the Source tab.
Scroll through the source analysis view.
Observe that program flow does not go into
if (sample_ready == 0)very often. Also, the same four or five lines of C appear, waiting forsample_readyto equal zero.Track the program flow:
Click the trace.c tab in the Code window to display the source view.
Move the Analysis window so that it does not overlay the source view in the Code window.
Click the Trace tab in the Analysis window to view the captured trace.
Select the first element in the captured trace.
Press Down to move through the trace, and observe the flow through the source code.
Scroll down through the captured trace until you see the first sample with the type
NoExecand the symbolic namemain\#80. This shows the trace sample whensample_readyequals zero.Select the trace sample with the type
NoExec.Press Down until the trace sample containing the call to
GetData()is highlighted. Observe that only the function calls to the three functions are traced, with a discontinuity between them. Figure 10.33 shows an example.
Trace ranges can not be used to capture unexpected program flow changes, such as exceptions handlers.
You can calculate the time elapsed during a discontinuity by measuring the time difference between the trace samples captured immediately before and after the discontinuity.
Setting trace ranges in conjunction with trace start and end points
the following in the RealView Debugger Command Line Reference Guide:
Chapter 2 RealView Debugger Commands for details of the DISASSEMBLE, ETM_CONFIG, and TRACE commands.
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