4.3.1. Using the Execution group

The Execution group contains:

Go

Click this button to start from the current location of the PC and run until the program:

  • ends

  • encounters an error condition

  • reaches a breakpoint

  • reaches a halt condition.

This option can also be used to resume program execution after stopping.

High-level Step Into

Click this button to step by lines of source code until the PC is located in another function or context. Normally, click this button to step up by one call level, but, depending on the function stepped into, it might cause the program to execute until it reaches source code.If the source line makes a function call, RealView Debugger steps into the function, unless there is no source code available for this function.

To see an example using this option:

  1. Connect to your target and load an image, for example dhrystone.axf.

  2. Click on the Src tab to view the source file dhry_1.c.

  3. Set a simple breakpoint by double-clicking on line 78.

  4. View the Output pane message:

    bi \DHRY_1\#78:5
    
  5. Click Go and the program begins execution and runs up to the breakpoint.

    The Output pane shows where execution stops.

  6. Click High-level Step Into once. A red box shows the location of the PC at line 91.

  7. Click High-level Step Into several times to move through the lines of source code.

In this example, RealView Debugger completes two high-level steps at the start. Therefore, the first high-level step takes the PC from the entry point to main(), and the second steps to after the function prolog.

Note

You can get to main() using Go (as above) or a single step. The single step executes (from the high-level code) up to main().

High-level Step Over

Click this button to step by lines of source code over function calls.

If the source line makes a call to a function, RealView Debugger executes the function completely before stopping, assuming that there is no stopping condition in the function call, for example a breakpoint.

Low-level Step Into

Click this button to step by instructions into functions. RealView Debugger executes the assembly language instruction at the current location of the PC.

Low-level Step Over

Click this button to step by instructions over function calls. RealView Debugger executes the assembly instruction at the current location of the PC.

If the assembly instruction makes a call to a function, RealView Debugger executes the function completely before stopping, assuming that there is no stopping condition in the function call, for example a breakpoint.

Go until Return

Click this button to start from the current PC in the current function and to run until it returns to the calling function.

Stop Execution

Click this button to stop the program currently executing on the target processor.

Note

In source code, repeated uses of low-level step commands might be necessary to complete execution if the source line contains multiple ARM instructions. Low-level step instructions, Low-level Step Into or Low-level Step Over, complete one assembly instruction at a time. This means that a call to a subroutine is treated as one instruction if you execute a step over.

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