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-rw-r--r--src/Machine.hs16
1 files changed, 12 insertions, 4 deletions
diff --git a/src/Machine.hs b/src/Machine.hs
index 5962469..e17f468 100644
--- a/src/Machine.hs
+++ b/src/Machine.hs
@@ -105,8 +105,12 @@ readA 6 s = with ars $ \rs -> do
(_,_,_,_,_,_,r) <- readIORef rs
return $ convertLong r s
readA 7 s = isSupervisor >>= \sup -> if sup
- then with ssp $ \sp -> readIORef sp
- else with usp $ \sp -> readIORef sp
+ then with ssp $ \sp -> do
+ v <- readIORef sp
+ return $ convertLong v s
+ else with usp $ \sp -> do
+ v <- readIORef sp
+ return $ convertLong v s
readA _ _ = return $ error "Incorrect Address register read"
@@ -160,8 +164,12 @@ writeA 6 s r = with ars $ \rs -> do
(r0,r1,r2,r3,r4,r5,r6) <- readIORef rs
writeIORef rs (r0,r1,r2,r3,r4,r5,combineLong r r6 s)
writeA 7 s r = isSupervisor >>= \sup -> if sup
- then with ssp $ \sp -> writeIORef sp r
- else with usp $ \sp -> writeIORef sp r
+ then with ssp $ \sp -> do
+ v <- readIORef sp
+ writeIORef sp $ combineLong r v s
+ else with usp $ \sp -> do
+ v <- readIORef sp
+ writeIORef sp $ combineLong r v s
writeA _ _ _ = return $ error "Incorrect Address register write"