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Development Tools User’s Manual
IXP2400/IXP2800 Network Processors
Developer Workbench
Same Instruction in More Than One Pipeline Stage:
It is possible, due to branching, for the same instruction to be in more than one pipeline stage. In
this case, the Pipe Stage marker on that instruction will have multiple arrowheads filled in, possibly
with different colors. This also means that there will be fewer than 6
markers in the thread window.
Context Swapping Issues:
When a context swap is in progress, the latter stages of the pipeline have instructions from the
context being swapped out and the early stages have instructions from the context being swapped
in. In this case, the thread windows for both contexts have Pipe Stage markers displayed. However,
the marker for each thread window will show arrowheads only for those stages in which the thread
has instructions.
For example, if a thread only has an instruction in stage 4, then its marker will only show a single
arrowhead, corresponding to stage 4. The other thread marker will show arrowheads for each of the
four stages in which it has instructions.
When a context is completely swapped out, its thread window displays all five arrowheads unfilled
to mark the instruction at which execution will resume when the context is swapped back in.
2.13.8.11
Document and Thread Window History
The Workbench maintains a history of previously visited document and thread windows along with
their scrolled positions. When a project is opened the history is cleared. A window and its scrolled
position gets added to the history when any of the following events occur
•
The user changes focus from one document window to another.
•
The user opens a new thread window.
•
The user opens a file.
•
The user creates a new file.
•
The user executes the
Go To Macro
command.
•
The user executes the
Go To Source
command.
•
The user executes the
Go To Instruction
command.
•
The user selects a different chip, Microengine, or thread to be displayed in a thread window
using the combo boxes in the toolbar of the thread window. A breakpoint is hit, causing a
different thread window to get focus
To move backwards through the history, the user selects
Back
from the
Window
menu. To move
forward through the history, the user selects
Forward
from the
Window
menu. There are toolbar
buttons for these commands that can be added to the toolbar by selecting
Customize
from the
Tools
menu.
If the user goes
Back
one or more times and then one of the events listed above occurs, all the
history that was forward of the window that was returned to will be deleted. For example, assume
the history contains windows A, B, C, D, E and F. If the user goes back to C then executes a
Go To
Macro
command, windows D, E and F are deleted from the history.