6785 - Radiant / Synplify Pro: Why does Postsyn reject the user's pre-synthesis constraints on an FDC file when Reveal Inserter is included in the project?

Description: 

The issue is caused by some differences in the behavior of the Verific and Synplify language parsers related to the handling of the escape characters in the instance name.

 

Solution:

This is not yet fixed by Synplify Pro and no timeline yet provided by the third-party tool.

Currently, there is a manual workaround so the user can resume work on the project. If the user removes the \ characters from the Synplify-generated .ldc file, then the constraints will be accepted by the database.

For users using the command line/tcl flow for radiant, this should be done in a few simple steps:

1. Run the normal flow up to synplify or synpwrap if the lattice-supplied wrapper is used.

2. Find the Synplify Output .ldc file (the .ldc file will be named <project name>_<implementation_name>.ldc')

3. Remove all the '\' characters from the constraints that are inside the '{}' brackets (a simple search and replace should do).

4. Run postsyn command, should not see any constraints dropped

5. Run the rest of the flow as normal

 

After this process, the user should see that no constraints are dropped.

 

For the GUI flow it would be as follows:

1. Run the project through synthesis.

2. Find the Synplify Output .ldc file, this should be located in the project implementation directory.

(the ldc file will be named <project name>_<implementation_name>.ldc')

Note that the succeeding screenshots are based on an example project only.

3. Remove all the '\' characters from the constraints that are inside the '{}' brackets (a simple search and replace should do).

4. Enter into the Radiant Tcl console the command found at the top of the postsyn report into the tcl console (the postsyn report will have the filename <project_name>_<implementation_name>_syn.psn)

Note: the path for the .vm file may need to be edited, the implementation directory would likely need to be appended to the front of the .vm file in the command, or the absolute path can be used.

5. After running postsyn in the tcl console, it should seen that 0 constraints are dropped

6. Run map and PAR flow as normal (Do not "run from start")

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