X-Git-Url: https://git.stderr.nl/gitweb?a=blobdiff_plain;f=Alu.hs;h=adc350f06dff902d2dc8250191f7c692270aa4e5;hb=ee868ded42dccf7679190420e8d348aa8d727b98;hp=f26bb831b45f85526d7b9b3f23ad9e70445bc0fd;hpb=d704c6a23e75f563d4816a0e01219fa7a3be266c;p=matthijs%2Fmaster-project%2Fc%CE%BBash.git

diff --git a/Alu.hs b/Alu.hs
index f26bb83..adc350f 100644
--- a/Alu.hs
+++ b/Alu.hs
@@ -16,13 +16,14 @@ program = [
             (High, High, dontcare) -- r1 = z (0)
           ]
 
-initial_state = (Regs Low High, Low, Low)
+--initial_state = (Regs Low High, Low, Low)
+initial_state = ((Low, High), Low, Low)
 
 -- Register bank
 
 type RegAddr = Bit
---type RegisterBankState = (Bit, Bit)
-data RegisterBankState = Regs { r0, r1 :: Bit} deriving (Show)
+type RegisterBankState = (Bit, Bit)
+--data RegisterBankState = Regs { r0, r1 :: Bit} deriving (Show)
 
 register_bank :: 
   (RegAddr, Bit, Bit) -> -- (addr, we, d)
@@ -30,49 +31,42 @@ register_bank ::
   (RegisterBankState, Bit) -- (s', o)
 
 register_bank (Low, Low, _) s = -- Read r0
-  (s, r0 s)
+  --(s, r0 s)
+  (s, fst s)
 
 register_bank (High, Low, _) s = -- Read r1
-  (s, r1 s)
+  --(s, r1 s)
+  (s, snd s)
 
 register_bank (addr, High, d) s = -- Write
   (s', dontcare)
   where
-    Regs r0 r1 = s
-    r0' = if addr == Low then d else r0
-    r1' = if addr == High then d else r1
-    s' = Regs r0' r1'
+    --Regs r0 r1 = s
+    (r0, r1) = s
+    r0' = case addr of Low -> d; High -> r0
+    r1' = case addr of High -> d; Low -> r1
+    --s' = Regs r0' r1'
+    s' = (r0', r1')
 
 -- ALU
 
 type AluOp = Bit
 
 alu :: AluOp -> Bit -> Bit -> Bit
+{-# NOINLINE alu #-}
 alu High a b = a `hwand` b
 alu Low a b = a `hwor` b
 
-salu :: AluOp -> Bit -> Bit -> () -> ((), Bit)
-salu High a b s = (s, a `hwand` b)
-salu Low a b s = (s, a `hwor` b)
-
 type ExecState = (RegisterBankState, Bit, Bit)
-exec :: (RegAddr, Bit, AluOp) -> ExecState -> (ExecState, ())
+exec :: (RegAddr, Bit, AluOp) -> ExecState -> (ExecState, (Bit))
 
 -- Read & Exec
-exec (addr, Low, op) s =
-  (s', ())
+exec (addr, we, op) s =
+  (s', z')
   where
     (reg_s, t, z) = s
-    (reg_s', t') = register_bank (addr, Low, dontcare) reg_s
+    (reg_s', t') = register_bank (addr, we, z) reg_s
     z' = alu op t' t
     s' = (reg_s', t', z')
 
--- Write
-exec (addr, High, op) s =
-  (s', ())
-  where
-    (reg_s, t, z) = s
-    (reg_s', _) = register_bank (addr, High, z) reg_s
-    s' = (reg_s', t, z)
-
 -- vim: set ts=8 sw=2 sts=2 expandtab: