diff --git a/decompiler/config/all-types.gc b/decompiler/config/all-types.gc
index 51b9acbb7..46cc9e13d 100644
--- a/decompiler/config/all-types.gc
+++ b/decompiler/config/all-types.gc
@@ -1623,10 +1623,6 @@
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~;
 
-;;;;;;;;;;;;;
-;; timer-h
-;;;;;;;;;;;;;
-
 (deftype timer-mode (uint32)
   (;(data  uint32 :offset 0 :size 32)
    (clks  uint8 :offset 0 :size 2)
@@ -1706,6 +1702,25 @@
     )
   )
 
+;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;;; TIMER               ;;;;;;;;;;;;;;;;;;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~;
+
+(define-extern timer-reset (function timer-bank none))
+(define-extern timer-count (function timer-bank uint))
+(define-extern disable-irq (function none))
+(define-extern enable-irq (function none))
+(define-extern stopwatch-init (function stopwatch none))
+(define-extern stopwatch-reset (function stopwatch none))
+(define-extern stopwatch-start (function stopwatch none))
+(define-extern stopwatch-stop (function stopwatch none))
+(define-extern stopwatch-begin (function stopwatch none))
+(define-extern stopwatch-end (function stopwatch none))
+(define-extern stopwatch-elapsed-ticks (function stopwatch uint))
+(define-extern stopwatch-elapsed-seconds (function stopwatch float))
+
 ;;;;;;;;;;;;;
 ;; vif-h
 ;;;;;;;;;;;;;
@@ -31709,25 +31724,6 @@
 ;;(define-extern sound-rpc-set-flava object) ;; unknown type
 ;;(define-extern sound-name object) ;; unknown type
 ;;(define-extern sound-rpc-continue-group object) ;; unknown type
-;;(define-extern timer-mode object) ;; unknown type
-;;(define-extern timer-hold-bank object) ;; unknown type
-;;(define-extern stopwatch object) ;; unknown type
-;;(define-extern *ticks-per-frame* object) ;; unknown type
-;;(define-extern profile-bar object) ;; unknown type
-;;(define-extern timer-bank object) ;; unknown type
-;;(define-extern profile-frame object) ;; unknown type
-(define-extern stopwatch-init function)
-(define-extern stopwatch-elapsed-seconds function)
-(define-extern stopwatch-begin function)
-(define-extern stopwatch-elapsed-ticks function)
-(define-extern disable-irq function)
-(define-extern timer-reset function)
-(define-extern enable-irq function)
-(define-extern stopwatch-start function)
-(define-extern timer-count function)
-(define-extern stopwatch-end function)
-(define-extern stopwatch-stop function)
-(define-extern stopwatch-reset function)
 ;;(define-extern vif-stat object) ;; unknown type
 ;;(define-extern vif-fbrst object) ;; unknown type
 ;;(define-extern vif-err object) ;; unknown type
diff --git a/goal_src/engine/ps2/timer-h.gc b/goal_src/engine/ps2/timer-h.gc
index 2aada4642..fbb92bce5 100644
--- a/goal_src/engine/ps2/timer-h.gc
+++ b/goal_src/engine/ps2/timer-h.gc
@@ -55,6 +55,7 @@
   :flag-assert         #x900000034
   )
 
+;; stopwatches are used to measure CPU clock cycles
 (deftype stopwatch (basic)
   ((prev-time-elapsed uint64  :offset-assert 8)
    (start-time        uint64  :offset-assert 16)
@@ -68,10 +69,10 @@
 ;; Confusing! What IS this measuring exactly? Hmm...
 (define *ticks-per-frame* (/ 2500000 256)) ;; 2 500 000 / 256 = 9765
 
-(defun timer-init ((bank timer-bank) (mode timer-mode))
+(defun timer-init ((timer timer-bank) (mode timer-mode))
   "Initiate a timer, start counting at a rate of 1 every 256 bus clocks (BUSCLK: ~147.456MHz)."
-  (set! (-> bank mode) mode)
-  (set! (-> bank count) 0)
+  (set! (-> timer mode) mode)
+  (set! (-> timer count) 0)
   )
 
 ;; segfaults OpenGOAL as it does not support ps2 EE timers
diff --git a/goal_src/engine/ps2/timer.gc b/goal_src/engine/ps2/timer.gc
index 2de4515b6..956082fb7 100644
--- a/goal_src/engine/ps2/timer.gc
+++ b/goal_src/engine/ps2/timer.gc
@@ -5,3 +5,152 @@
 ;; name in dgo: timer
 ;; dgos: GAME, ENGINE
 
+;; Sneakily disable these instructions for readibility (remove this later)
+;; SYNC is an EE instruction that waits for various memory access to be completed
+;; (this might not be necessary for x86_64)
+(defmacro .sync.l () `(none))
+(defmacro .sync.p () `(none))
+;; Copies the contents of a cop0 (system control) register to a gpr
+(defmacro .mfc0 (dest src) `(none))
+;; Copies the contents of a gpr to a cop0 (system control) register
+(defmacro .mtc0 (dest src) `(none))
+
+
+(defun timer-reset ((timer timer-bank))
+  "Reset a timer's counter to zero"
+  (.sync.l)
+  (set! (-> timer count) 0)
+  (.sync.l)
+  )
+
+(defun timer-count ((timer timer-bank))
+  "Return a timer's counter value"
+  (.sync.l)
+  (let ((count (-> timer count)))
+    (.sync.l)
+    count
+    )
+  )
+
+;; cop0 status register "interrupt enable" flag
+;; if cop0 status is needed anywhere else, move this elsewhere
+(defconstant COP0_STATUS_IE (the-as uint #x1))
+
+(defun disable-irq ()
+  "Disable all interrupts"
+  (rlet ((status :class gpr :type uint))
+    (let ((status-mask (lognot COP0_STATUS_IE)))
+      (.mfc0 status Status)
+      (logand! status status-mask) ;; should status-mask be replaced directly?
+      (.mtc0 Status status)
+      (.sync.p)
+      )
+    )
+  )
+
+(defun enable-irq ()
+  "Enable all interrupts"
+  (rlet ((status :class gpr :type uint))
+    (.mfc0 status Status)
+    (logior! status COP0_STATUS_IE)
+    (.mtc0 Status status)
+    (.sync.p)
+    )
+  )
+
+
+(defun stopwatch-init ((obj stopwatch))
+  "Init a stopwatch"
+  (set! (-> obj begin-level) 0)
+  (set! (-> obj prev-time-elapsed) 0)
+  (none)
+  )
+
+
+(defun stopwatch-reset ((obj stopwatch))
+  "Restart a stopwatch's times"
+  (set! (-> obj prev-time-elapsed) 0)
+  (when (> (-> obj begin-level) 0)
+    (let ((count 0))
+      (.mfc0 count Count)
+      (set! (-> obj start-time) count)
+      )
+    )
+  (none)
+  )
+
+(defun stopwatch-start ((obj stopwatch))
+  "Start a stopwatch from scratch"
+  (when (zero? (-> obj begin-level))
+    (set! (-> obj begin-level) 1)
+    (let ((count 0))
+      (.mfc0 count Count)
+      (set! (-> obj start-time) count)
+      )
+    )
+  (none)
+  )
+
+(defun stopwatch-stop ((obj stopwatch))
+  "Fully stop a stopwatch and save its elapsed time"
+  (when (> (-> obj begin-level) 0)
+    (set! (-> obj begin-level) 0)
+    (let ((count 0))
+      (let ((count 0))
+        (.mfc0 count Count) ; wrong register? a typo in a rlet? who knows.
+        (+! (-> obj prev-time-elapsed) (- count (-> obj start-time)))
+        )
+      )
+    )
+  (none)
+  )
+
+(defun stopwatch-begin ((obj stopwatch))
+  "Begin a stopwatch layer. Starts the stopwatch if it has not yet begun"
+  (when (zero? (-> obj begin-level))
+    (let ((count 0))
+      (.mfc0 count Count)
+      (set! (-> obj start-time) count)
+      )
+    )
+  (+! (-> obj begin-level) 1)
+  (none)
+  )
+
+;; NOTE : there is no guard against ending a stopwatch too many times!
+(defun stopwatch-end ((obj stopwatch))
+  "End a stopwatch layer. Stops the stopwatch if it has ended as many times as it has begun"
+  (+! (-> obj begin-level) -1)
+  (when (zero? (-> obj begin-level))
+    (set! (-> obj begin-level) 0)
+    (let ((count 0))
+      (.mfc0 count Count)
+      (+! (-> obj prev-time-elapsed) (- count (-> obj start-time)))
+      )
+    )
+  (none)
+  )
+
+(defun stopwatch-elapsed-ticks ((obj stopwatch))
+  "Returns the elapsed time so far (in clock cycles) of a stopwatch"
+  (let ((elapsed (-> obj prev-time-elapsed)))
+    (when (> (-> obj begin-level) 0)
+      (let ((count 0))
+        (.mfc0 count Count)
+        (+! elapsed (- count (-> obj start-time)))
+        ;(set! count elapsed) ;; ??
+        )
+      )
+    elapsed
+    )
+  )
+
+(defglobalconstant EE_SECONDS_PER_TICK (/ 1.0 3000000)) ;; 300MHz is a "decent enough" estimate
+(defmacro cpu-ticks-to-seconds (ticks)
+  `(* ,EE_SECONDS_PER_TICK ,ticks)
+  )
+(defun stopwatch-elapsed-seconds ((obj stopwatch))
+  "Returns the elapsed time so far (in seconds) of a stopwatch"
+  (cpu-ticks-to-seconds (stopwatch-elapsed-ticks obj))
+  )
+
diff --git a/goal_src/goal-lib.gc b/goal_src/goal-lib.gc
index 4f8a92c94..adb011f9c 100644
--- a/goal_src/goal-lib.gc
+++ b/goal_src/goal-lib.gc
@@ -201,7 +201,7 @@
            ;; otherwise don't ignore it.
            `(define ,name (lambda :name ,name :segment debug ,bindings ,@body))
            )
-       
+
        ;; function not loaded, set function to the nothing function.
        ;; we don't typecheck this.
        (define :no-typecheck #t ,name nothing)
@@ -355,6 +355,22 @@
   `(& (-> ,@args))
   )
 
+(defmacro logior! (place amount)
+  `(set! ,place (logior ,place ,amount))
+  )
+
+(defmacro logxor! (place amount)
+  `(set! ,place (logxor ,place ,amount))
+  )
+
+(defmacro lognor! (place amount)
+  `(set! ,place (lognor ,place ,amount))
+  )
+
+(defmacro logand! (place amount)
+  `(set! ,place (logand ,place ,amount))
+  )
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; Bit Macros
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;
diff --git a/test-goal-typecoherency.bat b/test-goal-typecoherency.bat
new file mode 100644
index 000000000..b16e29358
--- /dev/null
+++ b/test-goal-typecoherency.bat
@@ -0,0 +1,3 @@
+@echo off
+out\build\Release\bin\goalc-test --gtest_filter="*TypeConsistency*"
+pause
\ No newline at end of file