Print from UVM Library

[R_C1363912821]

Hi All,

Internal prints from UVM library are not in Sync with other prints. e.g. the UVM_ERROR print in log below (For Questa 10.0a running on windows) is out of sync as it displays the complete path of file from which print comes (that too without '/'):

# UVM_ERROR C:Users

# RCDocumentsUVMuvmsrc/base/uvm_phases.svh(1860) @ 1000: reporter [PH_TIMEOUT] Phase timeout of 1000 hit, phase 'run' ready to end

# UVM_WARNING @ 1000: run [OBJTN_CLEAR] Object 'common.run' cleared objection counts for run

Is there to way to modify the display so that all prints look alike.

Thanks,

RC

[jadec]

If you have C code, printing directly to the console or standard error. You could modify it to call a dpi exported SV function and print those messages through UVM as well. This would fix the synchronization and allow you to take advantage of filtering and counting in UVM.

[R_C1363912821]

Jadec, can you please provide example or steps required for this?

[jadec]

package my_pkg;

import uvm_pkg::*;
`include "uvm_macros.svh"

import "DPI-C" context function void c_hello();

export "DPI-C" function my_uvm_report_info;

function void my_uvm_report_info( string src, string msg, int line=0, string file="" );
  uvm_report_info( src, msg, line, file );
endfunction

endpackage

#include "svdpi.h" 
void c_hello() {
  my_uvm_report_info( "c_hello", "Hello World!", __LINE__, __FILE__ );
}

Calling c_hello from UVM gives:

UVM_INFO @ 0: reporter [RNTST] Running test my_test...

UVM_INFO /export/home/jadec/test/uvm/dpi_msg/c_hello.c(0) @ 0: reporter [c_hello] Hello World!

UVM_INFO @ 0: uvm_test_done [TEST_DONE] All end_of_test objections have been dropped. Calling global_stop_request()

[R_C1363912821]

Hi Jadec, Thanks for providing the example, the issue is that i dont have a C compiler so i get error

"# ** Fatal: (vsim-7019) Can't locate a C compiler for compilation of DPI export tasks/functions."

is there any other solution?

[jadec]

The assumption was that you were already using DPI. What are you doing that generates those other non-UVM messages?

[R_C1363912821]

There is nothing like non UVM, the prints that are out of sync are from the UVM library

# UVM_ERROR C:Users

# RCDocumentsUVMuvmsrc/base/uvm_phases.svh(1860) @ 1000: reporter [PH_TIMEOUT] Phase timeout of 1000 hit, phase 'run' ready to end

The issue is that it does not display the path properly (i.e. path is without '/')

[jadec]

So the problem is just that filename in your UVM messages is incorrect? One possible issue is that backslashes(\) may be handled incorrectly.

[R_C1363912821]

yes thats the only problem. I am running simulation on windows (Questa 10.0a), can this be a reason?

[jadec]

Windows uses backslashes for the path, but most tools will let you use forward slashes instead (which may provide a workaround).

UVM internally just uses `__FILE__ macro so this is probably an issue with how the simulator handles the filename. You can also disable the filename display entirely using defines: UVM_REPORT_DISABLE_FILE_LINE or UVM_REPORT_DISABLE_FILE during UVM compile.

[Bart]

Hi R_C

Seems like a possible bug in the UVM report_server that can't handle windows path separators..

If jadec's option to exclude the filename is not sufficient, you could try replacing the default report server with a custom implementation. This would allow you to detect & convert any problematic data for the report print..

class custom_server extends uvm_report_server;
    static bit initialized = init();

    static function bit init();
      uvm_report_global_server glob = new;
      custom_server mysrv = new;
      glob.set_server(mysrv);
    endfunction

    virtual function string compose_message( uvm_severity severity, string name, string id, string message, string filename, int    line);
     uvm_severity_type sev = uvm_severity_type'(severity);
     return { "# ", sev.name(), " (", filename, ") ", name, ": [", id, "]: ", message };
    endfunction
  endclass

Note that the static init() function is enough to set the mysrv instance of custom_server as the global report server.

All reports will now use the compose_message() function to create a string to be used in the report. The code in this example is simple - take a look at the default implementation in uvm_report_server.svh under src/base for a better example - but you should be able to use basic string processing to get the output you need..

[jadec]

You can pass a filename directly to UVM:

uvm_report_info( get_type_name(), "build", UVM_MEDIUM, "my\\bad\\nfile", 123 ); // NOTE: SV syntax requires escaping the backslash

UVM prints it correctly:

UVM_INFO my\bad\nfile(123) @ 0: uvm_test_top [my_test] build

So the filename string is likely getting corrupted before that.

[uwes]

hi,

you need a c-compiler to use DPI (even on windows you can get gcc) and link the result into the simulator.

[uwes]

yes thats the only problem. I am running simulation on windows (Questa 10.0a), can this be a reason?

the issue is that in sv a backslash is a special character. the windows filename "c:\foo\some\name" is just "c:" + "\f" + "oo" + "\s" + "ome" +"\n" + "ame". which results only for "\n" in a line break the other escape like sequences are ignored (are just "f" "s").

module test78;
       initial
       $display("c:\foo\some\name");
endmodule

ncsim> run
c:foosome
ame
ncsim: *W,RNQUIE: Simulation is complete.

btw: java for instance checks and allows only some characters to be prefixed by "\"

[jadec]

But in this case UVM, isn't including the filename directly (nor is the user), it's using `__FILE__ macro. Special characters in the filename should be properly escaped so the resulting string is correct (especially ones common for the OS).

[uwes]

so this finally boils down to a simulator issue and not to an UVM issue. as `__FILE__ and `__LINE__ are being defined by the compiler the compiler should take care of the correct string encoding on that platform.