added gitignore

.gitignore

@@ -0,0 +1,47 @@
+# ============================================================================
+# Simulation build artifacts — none of this belongs in the repo, it is all
+# regenerated by the run scripts (Makefile / run_vivado.sh / run.do / *.f).
+# ============================================================================
+
+# ---- Vivado / xsim ----
+xsim.dir/
+xsim.covdb/
+.Xil/
+*.wdb
+*.jou
+*.pb
+*.wcfg
+xvlog.log
+xelab.log
+xsim.log
+xsimcrash.log
+webtalk*
+usage_statistics_webtalk.*
+
+# ---- QuestaSim / ModelSim ----
+work/
+transcript
+vsim.wlf
+vsim_stacktrace.vstf
+modelsim.ini
+*.mti
+
+# ---- Cadence Xcelium / Incisive ----
+xcelium.d/
+INCA_libs/
+xrun.history
+xrun.log
+.simvision/
+*.shm/
+waves.shm/
+
+# ---- UVM / misc run output ----
+tr_db.log
+*.vcd
+
+# ---- Editor / OS junk ----
+.vscode/
+*~
+*.swp
+*.bak
+.DS_Store