Merging in the new codegen branch

[ghc-hetmet.git] / compiler / codeGen / StgCmmGran.hs

diff --git a/compiler/codeGen/StgCmmGran.hs b/compiler/codeGen/StgCmmGran.hs
new file mode 100644 (file)
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+++ b/compiler/codeGen/StgCmmGran.hs
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+-----------------------------------------------------------------------------
+--
+-- (c) The University of Glasgow -2006
+--
+-- Code generation relaed to GpH
+--     (a) parallel
+--     (b) GranSim
+--
+-----------------------------------------------------------------------------
+
+{-# OPTIONS -w #-}
+-- The above warning supression flag is a temporary kludge.
+-- While working on this module you are encouraged to remove it and fix
+-- any warnings in the module. See
+--     http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
+-- for details
+
+module StgCmmGran (
+       staticGranHdr,staticParHdr,
+       granThunk, granYield,
+       doGranAllocate
+  ) where
+
+-- This entire module consists of no-op stubs at the moment
+-- GranSim worked once, but it certainly doesn't any more
+-- I've left the calls, though, in case anyone wants to resurrect it
+
+import StgCmmMonad
+import Id
+import Cmm
+
+staticGranHdr :: [CmmLit]
+staticGranHdr = []
+
+staticParHdr :: [CmmLit]
+staticParHdr = []
+
+doGranAllocate :: VirtualHpOffset -> FCode ()
+-- Must be lazy in the amount of allocation
+doGranAllocate n = return ()
+
+granFetchAndReschedule :: [(Id,GlobalReg)] -> Bool -> FCode ()
+granFetchAndReschedule regs node_reqd = return ()
+
+granYield :: [LocalReg] -> Bool -> FCode ()
+granYield regs node_reqd = return ()
+
+granThunk :: Bool -> FCode ()
+granThunk node_points = return ()
+
+-----------------------------------------------------------------
+{-   ------- Everything below here is commented out -------------
+-----------------------------------------------------------------
+
+-- Parallel header words in a static closure
+staticParHdr :: [CmmLit]
+-- Parallel header words in a static closure
+staticParHdr = []
+
+staticGranHdr :: [CmmLit]
+-- Gransim header words in a static closure
+staticGranHdr = []
+
+doGranAllocate :: CmmExpr -> Code      
+-- macro DO_GRAN_ALLOCATE
+doGranAllocate hp 
+  | not opt_GranMacros = nopC
+  | otherwise         = panic "doGranAllocate"
+
+
+
+-------------------------
+granThunk :: Bool -> FCode ()
+-- HWL: insert macros for GrAnSim; 2 versions depending on liveness of node
+-- (we prefer fetchAndReschedule-style context switches to yield ones)
+granThunk node_points 
+  | node_points = granFetchAndReschedule [] node_points 
+  | otherwise   = granYield             [] node_points
+
+granFetchAndReschedule :: [(Id,GlobalReg)]  -- Live registers
+                      -> Bool                  -- Node reqd?
+                      -> Code
+-- Emit code for simulating a fetch and then reschedule.
+granFetchAndReschedule regs node_reqd
+  | opt_GranMacros && (node `elem` map snd regs || node_reqd)
+  = do { fetch
+       ; reschedule liveness node_reqd }
+  | otherwise
+  = nopC
+  where
+    liveness = mkRegLiveness regs 0 0
+
+fetch = panic "granFetch"
+       -- Was: absC (CMacroStmt GRAN_FETCH [])
+       --HWL: generate GRAN_FETCH macro for GrAnSim
+       --     currently GRAN_FETCH and GRAN_FETCH_AND_RESCHEDULE are miai
+
+reschedule liveness node_reqd = panic "granReschedule"
+       -- Was: absC  (CMacroStmt GRAN_RESCHEDULE [
+       --                mkIntCLit (I# (word2Int# liveness_mask)), 
+       --                mkIntCLit (if node_reqd then 1 else 0)])
+    
+
+-------------------------
+-- The @GRAN_YIELD@ macro is taken from JSM's  code for Concurrent Haskell. It
+-- allows to context-switch at  places where @node@ is  not alive (it uses the
+-- @Continue@ rather  than the @EnterNodeCode@  function in the  RTS). We emit
+-- this kind of macro at the beginning of the following kinds of basic bocks:
+-- \begin{itemize}
+--  \item Slow entry code where node is not alive (see @CgClosure.lhs@). Normally 
+--        we use @fetchAndReschedule@ at a slow entry code.
+--  \item Fast entry code (see @CgClosure.lhs@).
+--  \item Alternatives in case expressions (@CLabelledCode@ structures), provided
+--        that they are not inlined (see @CgCases.lhs@). These alternatives will 
+--        be turned into separate functions.
+
+granYield :: [(Id,GlobalReg)]   -- Live registers
+          -> Bool               -- Node reqd?
+          -> Code 
+
+granYield regs node_reqd
+  | opt_GranMacros && node_reqd = yield liveness
+  | otherwise                  = nopC
+  where
+     liveness = mkRegLiveness regs 0 0
+
+yield liveness = panic "granYield"
+       -- Was : absC (CMacroStmt GRAN_YIELD 
+        --                  [mkIntCLit (I# (word2Int# liveness_mask))])
+
+-}