This window displays all recorded snapshots in the current trace. Typically, there is one snapshot per event recorded. Other windows often display the times of various events or use time ranges to describe lifespans of various objects. Those times refer to the snap, which is a 0-up counter of snapshot records. Thus, a snapshot is a collection of observations of a target's state, usually while suspended, along with any mark up. Double-clicking a snapshot activates the selected point in time, i.e., the entire Debugger UI will navigate to the selected snapshot. NOTE: Navigating through time is not permitted while in Control Target mode.
The table has the following columns:
This action is available in the menu whenever the focused window has an associated snapshot. It will prompt for a new description for the current snapshot. This is a shortcut to modifying the description in the time table, but can be accessed outside of the time window.
This action is available when a trace is active. It prompts for a time schedule.
This is the same form as the notation in the sub-title of the Threads window. In many
cases, it is simply the snapshot number, e.g., 3, which will go to the snapshot
with key 3. It may optionally include an emulation schedule. For example, 3:10
will use snapshot 3 for an emulator's initial state and step 10 machine instructions on
snapshot 3's event thread. If the snapshot does not give an event thread, then the thread must
be specified in the expression, e.g., 3:t1-10. That expression will start at
snapshot 3, get the thread with key 1, and step it 10 machine instructions. The stepping
commands can be repeated any number of times, separated by semicolons, to step threads in a
specified sequence. For example, 3:t1-10;t2-5 will do the same as before, then get
thread 2 and step it 5 times.
The emulator's state can also be patched by the schedule. Instead of specifying the number
of steps, write a Sleigh statement, e.g., 3:t1-{r0=0x1234};10. This will
start at snapshot 3, patch thread 1's r0 to 0x1234, then step 10 instructions. As for steps,
the thread key may be omitted for Sleigh commands. Each command without a thread specified
implicitly uses the one from the previous command, or in the case of the first command, the
event thread. Only one Sleigh statement is permitted per command.
A second command sequence may be appended, following a dot, to command the emulator at the
level of p-code operations as well. This is particularly useful when debugging a processor
specification. See the P-code Stepper
window. For example, 3:2.10 will start at snapshot 3 and step the event thread 2
machine instructions then 10 p-code operations. The same thread-by-thread sequencing and state
patching commands are allowed in the p-code command sequence. NOTE: the entire
instruction sequence precedes the entire p-code sequence, i.e., only a single dot is allowed.
Once the schedule enters p-code mode, it cannot re-enter instruction mode.
This toggle action is always available in the drop-down actions of the Time window. It is enabled by default. The emulation service, which enables trace extrapolation and interpolation, writes emulated state into the trace's scratch space, which comprises all negative snaps. When this toggle is enabled, those snapshots are hidden. They can be displayed by disabling this toggle. Note that navigating into scratch space may cause temporary undefined behavior in some windows, and may prevent interaction with the target.