remove empty dir

[ghc-hetmet.git] / ghc / compiler / codeGen / CgHeapery.lhs

diff --git a/ghc/compiler/codeGen/CgHeapery.lhs b/ghc/compiler/codeGen/CgHeapery.lhs
index 5e6c122..184af90 100644 (file)
--- a/ghc/compiler/codeGen/CgHeapery.lhs
+++ b/ghc/compiler/codeGen/CgHeapery.lhs
@@ -1,7 +1,7 @@
 %
 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
 %
-% $Id: CgHeapery.lhs,v 1.41 2004/09/30 10:35:45 simonpj Exp $
+% $Id: CgHeapery.lhs,v 1.47 2005/06/21 10:44:41 simonmar Exp $
 %
 \section[CgHeapery]{Heap management functions}
 
@@ -23,7 +23,6 @@ module CgHeapery (
 
 #include "HsVersions.h"
 
-import Constants       ( mIN_UPD_SIZE )
 import StgSyn          ( AltType(..) )
 import CLabel          ( CLabel, mkRtsCodeLabel )
 import CgUtils         ( mkWordCLit, cmmRegOffW, cmmOffsetW,
@@ -34,14 +33,14 @@ import CgTicky              ( staticTickyHdr, tickyDynAlloc, tickyAllocHeap )
 import CgParallel      ( staticGranHdr, staticParHdr, doGranAllocate )
 import CgStackery      ( getFinalStackHW, getRealSp )
 import CgCallConv      ( mkRegLiveness )
-import ClosureInfo     ( closureSize, closureUpdReqd,
-                         staticClosureNeedsLink, 
-                         mkConInfo, 
+import ClosureInfo     ( closureSize, staticClosureNeedsLink, 
+                         mkConInfo,  closureNeedsUpdSpace,
                          infoTableLabelFromCI, closureLabelFromCI,
                          nodeMustPointToIt, closureLFInfo,                     
                          ClosureInfo )
 import SMRep           ( CgRep(..), cgRepSizeW, separateByPtrFollowness,
-                         WordOff, fixedHdrSize, isVoidArg, primRepToCgRep )
+                         WordOff, fixedHdrSize, thunkHdrSize,
+                         isVoidArg, primRepToCgRep )
 
 import Cmm             ( CmmLit(..), CmmStmt(..), CmmExpr(..), GlobalReg(..),
                          CmmReg(..), hpReg, nodeReg, spReg )
@@ -54,10 +53,9 @@ import TyCon         ( tyConPrimRep )
 import CostCentre      ( CostCentreStack )
 import Util            ( mapAccumL, filterOut )
 import Constants       ( wORD_SIZE )
+import Packages                ( HomeModules )
 import Outputable
 
-import GLAEXTS
-
 \end{code}
 
 
@@ -125,7 +123,8 @@ getHpRelOffset virtual_offset
 
 \begin{code}
 layOutDynConstr, layOutStaticConstr
-       :: DataCon      
+       :: HomeModules
+       -> DataCon      
        -> [(CgRep,a)]
        -> (ClosureInfo,
            [(a,VirtualHpOffset)])
@@ -133,13 +132,13 @@ layOutDynConstr, layOutStaticConstr
 layOutDynConstr    = layOutConstr False
 layOutStaticConstr = layOutConstr True
 
-layOutConstr is_static data_con args
-   = (mkConInfo is_static data_con tot_wds ptr_wds,
+layOutConstr  is_static hmods data_con args
+   = (mkConInfo hmods is_static data_con tot_wds ptr_wds,
       things_w_offsets)
   where
-    (tot_wds,           -- #ptr_wds + #nonptr_wds
-     ptr_wds,           -- #ptr_wds
-     things_w_offsets) = mkVirtHeapOffsets args
+    (tot_wds,           --  #ptr_wds + #nonptr_wds
+     ptr_wds,           --  #ptr_wds
+     things_w_offsets) = mkVirtHeapOffsets False{-not a thunk-} args
 \end{code}
 
 @mkVirtHeapOffsets@ always returns boxed things with smaller offsets
@@ -148,8 +147,9 @@ list
 
 \begin{code}
 mkVirtHeapOffsets
-         :: [(CgRep,a)]        -- Things to make offsets for
-         -> (WordOff,          -- *Total* number of words allocated
+         :: Bool               -- True <=> is a thunk
+         -> [(CgRep,a)]        -- Things to make offsets for
+         -> (WordOff,          -- _Total_ number of words allocated
              WordOff,          -- Number of words allocated for *pointers*
              [(a, VirtualHpOffset)])
                                -- Things with their offsets from start of 
@@ -157,7 +157,7 @@ mkVirtHeapOffsets
 
 -- First in list gets lowest offset, which is initial offset + 1.
 
-mkVirtHeapOffsets things
+mkVirtHeapOffsets is_thunk things
   = let non_void_things                      = filterOut (isVoidArg . fst) things
        (ptrs, non_ptrs)              = separateByPtrFollowness non_void_things
        (wds_of_ptrs, ptrs_w_offsets) = mapAccumL computeOffset 0 ptrs
@@ -165,8 +165,11 @@ mkVirtHeapOffsets things
     in
     (tot_wds, wds_of_ptrs, ptrs_w_offsets ++ non_ptrs_w_offsets)
   where
+    hdr_size   | is_thunk   = thunkHdrSize
+               | otherwise  = fixedHdrSize
+
     computeOffset wds_so_far (rep, thing)
-      = (wds_so_far + cgRepSizeW rep, (thing, fixedHdrSize + wds_so_far))
+      = (wds_so_far + cgRepSizeW rep, (thing, hdr_size + wds_so_far))
 \end{code}
 
 
@@ -187,26 +190,36 @@ mkStaticClosureFields
        -> [CmmLit]             -- Payload
        -> [CmmLit]             -- The full closure
 mkStaticClosureFields cl_info ccs caf_refs payload
-  = mkStaticClosure info_lbl ccs payload padding_wds static_link_field
+  = mkStaticClosure info_lbl ccs payload padding_wds 
+       static_link_field saved_info_field
   where
     info_lbl = infoTableLabelFromCI cl_info
 
-    upd_reqd = closureUpdReqd cl_info
+    -- CAFs must have consistent layout, regardless of whether they
+    -- are actually updatable or not.  The layout of a CAF is:
+    --
+    --        3 saved_info
+    --        2 static_link
+    --        1 indirectee
+    --        0 info ptr
+    --
+    -- the static_link and saved_info fields must always be in the same
+    -- place.  So we use closureNeedsUpdSpace rather than
+    -- closureUpdReqd here:
+
+    is_caf = closureNeedsUpdSpace cl_info
 
-    -- for the purposes of laying out the static closure, we consider all
-    -- thunks to be "updatable", so that the static link field is always
-    -- in the same place.
     padding_wds
-       | not upd_reqd = []
-       | otherwise    = replicate n (mkIntCLit 0) -- a bunch of 0s
-       where n = max 0 (mIN_UPD_SIZE - length payload)
+       | not is_caf = []
+       | otherwise  = ASSERT(null payload) [mkIntCLit 0]
 
-       -- We always have a static link field for a thunk, it's used to
-       -- save the closure's info pointer when we're reverting CAFs
-       -- (see comment in Storage.c)
     static_link_field
-       | upd_reqd || staticClosureNeedsLink cl_info = [static_link_value]
-       | otherwise                                  = []
+       | is_caf || staticClosureNeedsLink cl_info = [static_link_value]
+       | otherwise                                = []
+
+    saved_info_field
+       | is_caf     = [mkIntCLit 0]
+       | otherwise  = []
 
        -- for a static constructor which has NoCafRefs, we set the
        -- static link field to a non-zero value so the garbage
@@ -215,14 +228,16 @@ mkStaticClosureFields cl_info ccs caf_refs payload
        | caf_refs      = mkIntCLit 0
        | otherwise     = mkIntCLit 1
 
+
 mkStaticClosure :: CLabel -> CostCentreStack -> [CmmLit]
-  -> [CmmLit] -> [CmmLit] -> [CmmLit]
-mkStaticClosure info_lbl ccs payload padding_wds static_link_field
+  -> [CmmLit] -> [CmmLit] -> [CmmLit] -> [CmmLit]
+mkStaticClosure info_lbl ccs payload padding_wds static_link_field saved_info_field
   =  [CmmLabel info_lbl]
   ++ variable_header_words
   ++ payload
   ++ padding_wds
   ++ static_link_field
+  ++ saved_info_field
   where
     variable_header_words
        =  staticGranHdr