Differences

This shows you the differences between two versions of the page.

--- tools:start [2023/04/07 08:56]
rajit [Tools]
+++ tools:start [2023/06/23 11:23] (current)
rajit [Tools]
@@ Line 8: / Line 8: @@
    * [[prs2sim|prs2sim]]: a production rule to sim file converter
    * [[ext2sp|ext2sp]]: converts magic extract files into a hierarchical spice file
+   * [[tools:layout:|Layout generation]]
    * [[lvp|lvp]]: layout versus production rules
@@ Line 22: / Line 23: @@
    * [[http://opencircuitdesign.com/magic/index.html|magic]]: The Magic VLSI layout editor
    * [[http://opencircuitdesign.com/irsim/index.html|irsim]]: A switch-level circuit simulator
-   * Gemini: a netlist comparison for strict layout-versus-schematic checking {{:tools:gemini-2.7.2.tar.gz|Gemini}}
+   * Layout versus schematic (LVS) checking:
+      * Gemini: a netlist comparison for strict layout-versus-schematic checking {{:tools:gemini-2.7.2.tar.gz|Gemini}}
+      * [[http://opencircuitdesign.com/netgen/index.html|netgen]]: another tool for LVS
 Two useful concepts to keep in mind when using the ACT tools are //expanded names// and //mangled names//.
@@ Line 40: / Line 43: @@
 ===== Mangled names =====
+Expanded ACT type names can contain characters like ''<'','' >'', and '','' (among others). Instances can have names like ''a[3].b[5].z'', including the characters ''['', '']'', and ''.''. When exporting an ACT design to another format for use by a third-party tool, names with such characters in them can be potentially problematic. A good example of this is when exporting a SPICE netlist---different versions of SPICE have different syntactic restrictions. To handle this in a disciplined manner, the ACT library has the notion of a //mangled// name. A mangled name is generated by re-writing a user-specified list of special characters with an underscore and a number/character combination. This mapping is invertible, so a name can be unmangled as well. The set of characters to be mangled is specified in the ACT configuration option ''act.mangle_string'' (usually found in the global configuration file ''global.conf'').
+The standard name mangling prefix character is an underscore. Name mangling operates character-by-character as follows:
+   *  An underscore is replaced by two underscores.
+   * A character that is not in the mangle string is a pass-through, so it is not modified.
+   * If a character is at position k in the name mangling string, it is replaced with an underscore followed by k. The position character is 0 to 9 for positions 0 to 9, followed by a-z. Up to 36 characters can be mangled.
+Name mangling can at most double the length of the string.
+Process names have a special case in terms of name mangling. If an expanded process has no parameters, its mangled name is obtained simply be omitting the trailing ''<>''. This is to make the output more readable when templates are not being used.