Xilinx Constraints Guide

Chapter 2: Entry Strategies for Xilinx Constraints
If the wildcard character is used as part of a longer instance name, the wildcard
represents one or more characters at that position.
In a location, you can use a wildcard character for either the row number or the column
number. For example, the following constraint specifies placement of any instance under
the hierarchy of loads_of_logic in any SLICE in column 8.
INST "/loads_of_logic/*" LOC=SLICE_X*Y8;
Wildcard characters cannot be used for both the row number and the column number in
a single constraint, since such a constraint is meaningless.
Traversing Hierarchies
Top-level block names (design names) are ignored when searching for instance name
matches. You can use the asterisk wildcard character (*) to traverse the hierarchy of a
design within a UCF and NCF file. The following syntax applies (where level1 is an
example hierarchy level name).
UCF Design Hierarchy
* Traverses all levels of the hierarchy
level1/* Traverses all blocks in level1 and below
level1/*/ Traverses all blocks in the level1 hierarchy
level but no further
Consider the following design hierarchy.
UCF Design Hierarchy
With the example design hierarchy, the following specifications illustrate the scope of
the wildcard.
INST * =>
INST /* =>
INST /*/ =>
INST $A1/* =>
INST $A1/*/ =>
INST $A1/*/* =>
INST $A1/*/*/ =>
INST $A1/*/*/* =>
INST $A1/*/*/*/ =>
INST /*/*22/ =>
INST /*/*22 =>
Constraints Guide
34 www.xilinx.com UG625 (v. 13.2) July 6, 2011