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tag engine now allows from simultaneous retire and request - but had to use unsafe

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This commit is contained in:
Yehowshua Immanuel 2025-03-25 01:15:49 -04:00
parent 5588fafebd
commit ed8e0b8337
2 changed files with 62 additions and 34 deletions
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83
bs/TagEngine.bs
View file

@ -34,12 +34,8 @@ mkTagEngine =
methodRequestTagCalled :: PulseWire
methodRequestTagCalled <- mkPulseWire
methodRetireTagCalled :: PulseWire
methodRetireTagCalled <- mkPulseWire
tagResponse :: RWire UIntLog2N(numTags)
tagResponse <- mkRWireSBR
methodRetireTagCalledValid :: RWire UIntLog2N(numTags)
methodRetireTagCalledValid <- mkUnsafeRWire
debugOnce <- mkReg True
@ -53,15 +49,48 @@ mkTagEngine =
$display "inUseVec : " (fshow |> readVReg inUseVec)
$display "stackPtr : " (fshow stackPtr)
debugOnce := False
<+>
rules
when (methodRequestTagCalled && methodRetireTagCalled) ==>
"update stack pointer": when True ==>
do
$display "ho ho ho"
-- let
-- nextStackPtr =
-- case of (methodRequestTagCalled, methodRetireTagCalled) of
-- (True, True) ->
stackPtr :=
case (methodRequestTagCalled, methodRetireTagCalledValid.wget) of
(True, Just tag) -> stackPtr
(True, Nothing) ->
case stackPtr of
Just 0 -> Nothing
Just sampledStackPtr -> Just |> sampledStackPtr - 1
Nothing -> Nothing
(False, Just tag) ->
case stackPtr of
Just sampledStackPtr -> Just |> sampledStackPtr + 1
Nothing -> Nothing
(False, Nothing) -> stackPtr
"update free stack": when True ==>
do
case (methodRequestTagCalled, methodRetireTagCalledValid.wget) of
(True, Just tag) -> do action {}
(True, Nothing) -> do action {}
(False, Just tag) -> do
case stackPtr of
Just sampledStackPtr -> do
(select freeStackVec (sampledStackPtr + 1)) := tag
Nothing -> do
(select freeStackVec 0) := tag
(False, Nothing) -> do action {}
"update in use": when True ==>
do
case (methodRequestTagCalled, methodRetireTagCalledValid.wget) of
(True, Just tag) -> do action {}
(True, Nothing) ->
case stackPtr of
Just sampledStackPtr -> do
(select inUseVec sampledStackPtr) := True
Nothing -> do action {}
(False, Just tag) -> do
(select inUseVec tag) := False
(False, Nothing) -> do action {}
counter <- mkReg(0 :: UIntLog2N(numTags))
return $
@ -71,23 +100,19 @@ mkTagEngine =
requestTag =
do
methodRequestTagCalled.send
stackPtr :=
if sampledStackPtr == 0
then Nothing
else Just |> sampledStackPtr - 1
(select inUseVec sampledStackPtr) := True
return |> Just |> readReg (select freeStackVec sampledStackPtr)
when
Just sampledStackPtr <- stackPtr
case methodRetireTagCalledValid.wget of
Just tag -> do
return |> Just tag
Nothing -> do
return |>
case stackPtr of
Just sampledStackPtr ->
Just |> readReg (select freeStackVec sampledStackPtr)
Nothing -> Nothing
-- retireTag isn't guarded so its up to external module to only attempt to
-- retire valid tags... At any rate, we can notify the requestor of failures
-- to retire tags - although the requestor can merely ignore this
-- notification.
retireTag :: UIntLog2N(numTags) -> ActionValue BasicResult
retireTag tag =
do
methodRetireTagCalled.send
let
tagValid = tag < reifiedNumTags
tagInUse = readReg (select inUseVec tag)
@ -97,9 +122,7 @@ mkTagEngine =
Just n -> n + 1
if (tagValid && tagInUse)
then do
(select inUseVec tag) := False
(select freeStackVec nextStackPtrUint) := tag
stackPtr := Just nextStackPtrUint
methodRetireTagCalledValid.wset tag
return Success
else do
return Failure

13
bs/Tests/TagEngineTester.bs
View file

@ -7,6 +7,7 @@ mkTagEngineTester :: Module Empty
mkTagEngineTester = do
tagEngine :: TagEngine 5 <- mkTagEngine
count :: Reg (UInt 4) <- mkReg 0;
runOnce :: Reg Bool <- mkReg False
s :: ActionSeq
s <-
@ -30,7 +31,11 @@ mkTagEngineTester = do
|> do requestTagAction
|> do requestTagAction
|> do retireTagAction 3
|> do requestTagAction
|> do $display "BEGIN TRY SIMULTANEOUS RETIRE and REQUEST"
|> do
retireTagAction 4
requestTagAction
|> do $display "END TRY SIMULTANEOUS RETIRE and REQUEST"
|> do requestTagAction
|> do retireTagAction 4
|> do retireTagAction 4
@ -42,7 +47,7 @@ mkTagEngineTester = do
addRules $
rules
"testIncrement": when (count < 10) ==>
"testIncrement": when (runOnce == False) ==>
do
count := count + 1
s.start
s.start
runOnce := True