diff --git a/.circleci/build-verilator.sh b/.circleci/build-verilator.sh
index 2c0b6a13..acd038fb 100755
--- a/.circleci/build-verilator.sh
+++ b/.circleci/build-verilator.sh
@@ -23,7 +23,7 @@ if [ ! -d "$LOCAL_VERILATOR_DIR" ]; then
     run "mkdir -p $REMOTE_CHIPYARD_DIR"
     copy $LOCAL_CHIPYARD_DIR/ $SERVER:$REMOTE_CHIPYARD_DIR
 
-    run "make -C $REMOTE_CHIPYARD_DIR/sims/verisim VERILATOR_INSTALL_DIR=$REMOTE_VERILATOR_DIR verilator_install"
+    run "make -C $REMOTE_SIM_DIR VERILATOR_INSTALL_DIR=$REMOTE_VERILATOR_DIR verilator_install"
 
     # copy so that circleci can cache
     mkdir -p $LOCAL_CHIPYARD_DIR
diff --git a/.circleci/check-commit.sh b/.circleci/check-commit.sh
index 4ad48ed5..630bbd08 100755
--- a/.circleci/check-commit.sh
+++ b/.circleci/check-commit.sh
@@ -26,7 +26,7 @@ search () {
     done
 }
 
-submodules=("boom" "firechip" "hwacha" "icenet" "rocket-chip" "sifive-blocks" "sifive-cache" "testchipip")
+submodules=("boom" "hwacha" "icenet" "rocket-chip" "sifive-blocks" "sifive-cache" "testchipip")
 dir="generators"
 
 search
diff --git a/.circleci/config.yml b/.circleci/config.yml
index 42397ea8..e03f2a9c 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -78,14 +78,14 @@ jobs:
             - checkout
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Build Verilator
                 command: |
                     .circleci/build-verilator.sh
                 no_output_timeout: 120m
             - save_cache:
-                key: verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                key: verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
                 paths:
                     - "/home/riscvuser/verilator"
     prepare-example:
@@ -108,7 +108,7 @@ jobs:
                     - riscv-tools-installed-v1-{{ checksum "../riscv-tools.hash" }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Building the example subproject using Verilator
                 command: .circleci/do-rtl-build.sh example
@@ -137,7 +137,7 @@ jobs:
                     - riscv-tools-installed-v1-{{ checksum "../riscv-tools.hash" }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Building the boomexample subproject using Verilator
                 command: .circleci/do-rtl-build.sh boomexample
@@ -166,7 +166,7 @@ jobs:
                     - riscv-tools-installed-v1-{{ checksum "../riscv-tools.hash" }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Building the boomrocketexample subproject using Verilator
                 command: .circleci/do-rtl-build.sh boomrocketexample
@@ -195,7 +195,7 @@ jobs:
                     - riscv-tools-installed-v1-{{ checksum "../riscv-tools.hash" }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Building the boom subproject using Verilator
                 command: .circleci/do-rtl-build.sh boom
@@ -224,7 +224,7 @@ jobs:
                     - riscv-tools-installed-v1-{{ checksum "../riscv-tools.hash" }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Building the rocketchip subproject using Verilator
                 command: .circleci/do-rtl-build.sh rocketchip
@@ -253,7 +253,7 @@ jobs:
                     - esp-tools-installed-v1-{{ checksum "../esp-tools.hash" }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Building the hwacha subproject using Verilator
                 command: .circleci/do-rtl-build.sh hwacha
@@ -282,7 +282,7 @@ jobs:
                     - example-{{ .Branch }}-{{ .Revision }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Run example tests
                 command: .circleci/run-tests.sh example
@@ -306,7 +306,7 @@ jobs:
                     - boomexample-{{ .Branch }}-{{ .Revision }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Run boomexample tests
                 command: .circleci/run-tests.sh boomexample
@@ -330,7 +330,7 @@ jobs:
                     - boomrocketexample-{{ .Branch }}-{{ .Revision }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Run boomrocketexample tests
                 command: .circleci/run-tests.sh boomrocketexample
@@ -354,7 +354,7 @@ jobs:
                     - boom-{{ .Branch }}-{{ .Revision }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Run boom tests
                 command: .circleci/run-tests.sh boom
@@ -378,7 +378,7 @@ jobs:
                     - rocketchip-{{ .Branch }}-{{ .Revision }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Run rocketchip tests
                 command: .circleci/run-tests.sh rocketchip
@@ -402,7 +402,7 @@ jobs:
                     - hwacha-{{ .Branch }}-{{ .Revision }}
             - restore_cache:
                 keys:
-                    - verilator-installed-v3-{{ checksum "sims/verisim/verilator.mk" }}
+                    - verilator-installed-v3-{{ checksum "sims/verilator/verilator.mk" }}
             - run:
                 name: Run hwacha tests
                 command: .circleci/run-tests.sh hwacha
diff --git a/.circleci/defaults.sh b/.circleci/defaults.sh
index a17dca78..91b8f589 100755
--- a/.circleci/defaults.sh
+++ b/.circleci/defaults.sh
@@ -23,7 +23,7 @@ REMOTE_RISCV_DIR=$REMOTE_WORK_DIR/riscv-tools-install
 REMOTE_ESP_DIR=$REMOTE_WORK_DIR/esp-tools-install
 REMOTE_CHIPYARD_DIR=$REMOTE_WORK_DIR/chipyard
 REMOTE_VERILATOR_DIR=$REMOTE_WORK_DIR/verilator
-REMOTE_SIM_DIR=$REMOTE_CHIPYARD_DIR/sims/verisim
+REMOTE_SIM_DIR=$REMOTE_CHIPYARD_DIR/sims/verilator
 
 # local variables (aka within the docker container)
 LOCAL_CHECKOUT_DIR=$HOME/project
@@ -31,7 +31,7 @@ LOCAL_RISCV_DIR=$HOME/riscv-tools-install
 LOCAL_ESP_DIR=$HOME/esp-tools-install
 LOCAL_CHIPYARD_DIR=$LOCAL_CHECKOUT_DIR
 LOCAL_VERILATOR_DIR=$HOME/verilator
-LOCAL_SIM_DIR=$LOCAL_CHIPYARD_DIR/sims/verisim
+LOCAL_SIM_DIR=$LOCAL_CHIPYARD_DIR/sims/verilator
 
 # key value store to get the build strings
 declare -A mapping
diff --git a/common.mk b/common.mk
index 68a7e632..11e8c167 100644
--- a/common.mk
+++ b/common.mk
@@ -73,8 +73,9 @@ $(HARNESS_SMEMS_FILE) $(HARNESS_SMEMS_FIR): $(HARNESS_SMEMS_CONF)
 verilog: $(sim_vsrcs)
 
 #########################################################################################
-# helper rules to run simulator
+# helper rules to run simulations
 #########################################################################################
+.PHONY: run-binary run-fast
 run-binary: $(sim)
 	(set -o pipefail && $(sim) $(PERMISSIVE_ON) +max-cycles=$(timeout_cycles) $(SIM_FLAGS) $(VERBOSE_FLAGS) $(PERMISSIVE_OFF) $(BINARY) 3>&1 1>&2 2>&3 | spike-dasm > $(sim_out_name).out)
 
@@ -90,6 +91,8 @@ run-binary-fast: $(sim)
 run-binary-debug: $(sim_debug)
 	(set -o pipefail && $(sim_debug) $(PERMISSIVE_ON) +max-cycles=$(timeout_cycles) $(SIM_FLAGS) $(VERBOSE_FLAG) $(WAVEFORM_FLAG) $(PERMISSIVE_OFF) $(BINARY) 3>&1 1>&2 2>&3 | spike-dasm > $(sim_out_name).out)
 
+run-fast: run-asm-tests-fast run-bmark-tests-fast
+
 #########################################################################################
 # run assembly/benchmarks rules
 #########################################################################################
diff --git a/sims/vsim/.gitignore b/sims/vcs/.gitignore
similarity index 100%
rename from sims/vsim/.gitignore
rename to sims/vcs/.gitignore
diff --git a/sims/vsim/Makefile b/sims/vcs/Makefile
similarity index 99%
rename from sims/vsim/Makefile
rename to sims/vcs/Makefile
index 6364d2f8..6caf5919 100644
--- a/sims/vsim/Makefile
+++ b/sims/vcs/Makefile
@@ -56,6 +56,7 @@ VCS_NONCC_OPTS = \
 	-error=PCWM-L \
 	-timescale=1ns/10ps \
 	-quiet \
+	-q \
 	+rad \
 	+v2k \
 	+vcs+lic+wait \
diff --git a/sims/verisim/.gitignore b/sims/verilator/.gitignore
similarity index 100%
rename from sims/verisim/.gitignore
rename to sims/verilator/.gitignore
diff --git a/sims/verisim/Makefile b/sims/verilator/Makefile
similarity index 100%
rename from sims/verisim/Makefile
rename to sims/verilator/Makefile
diff --git a/sims/verisim/verilator.mk b/sims/verilator/verilator.mk
similarity index 100%
rename from sims/verisim/verilator.mk
rename to sims/verilator/verilator.mk