[nix] add vcs-prof-vcd derivation

nix/t1/run/default.nix

@@ -12,6 +12,7 @@
 let
   runVerilatorEmu = callPackage ./run-verilator-emu.nix { };
   runVCSEmu = callPackage ./run-vcs-emu.nix { };
+  runFsdb2vcd = callPackage ./run-fsdb2vcd.nix { };
 
   # cases is now { mlir = { hello = ...; ...  }; ... }
   emuAttrs = lib.pipe cases [
@@ -32,6 +33,7 @@ let
             verilator-emu-trace = runVerilatorEmu verilator-emu-trace case;
             vcs-emu = runVCSEmu vcs-emu case;
             vcs-emu-trace = runVCSEmu vcs-emu-trace case;
+            vcs-prof-vcd = runFsdb2vcd (runVCSEmu vcs-emu-trace case);
           };
         in
         # Now we have { caseName = "hello", case = <derivation> }

nix/t1/run/run-fsdb2vcd.nix

@@ -0,0 +1,22 @@
+{ lib, stdenvNoCC, vcs-fhs-env }:
+vcs-emu-trace:
+
+let
+  caseName = vcs-emu-trace.caseName;
+in
+stdenvNoCC.mkDerivation (finalAttr: {
+  name = "${caseName}-vcs-prof-vcd";
+
+  __noChroot = true;
+
+  dontUnpack = true;
+
+  buildCommand = ''
+    mkdir -p "$out"
+
+    fhsEnv="${vcs-fhs-env}/bin/vcs-fhs-env"
+    "$fhsEnv" -c "fsdb2vcd ${vcs-emu-trace}/*.fsdb -o ${caseName}.prof.vcd -s /TestBench/verification/profData"
+
+    cp -t "$out" "${caseName}.prof.vcd"
+  '';
+})