remove some redundant SRT-related stuff

compiler/codeGen/StgCmm.hs

@@ -149,10 +149,10 @@ cgTopRhs :: Id -> StgRhs -> FCode CgIdInfo
 cgTopRhs bndr (StgRhsCon _cc con args)
   = forkStatics (cgTopRhsCon bndr con args)
 
-cgTopRhs bndr (StgRhsClosure cc bi fvs upd_flag srt args body)
+cgTopRhs bndr (StgRhsClosure cc bi fvs upd_flag _srt args body)
   = ASSERT(null fvs)    -- There should be no free variables
     setSRTLabel (mkSRTLabel (idName bndr) (idCafInfo bndr)) $
-    forkStatics (cgTopRhsClosure bndr cc bi upd_flag srt args body)
+    forkStatics (cgTopRhsClosure bndr cc bi upd_flag args body)
 
 
 ---------------------------------------------------------------

compiler/codeGen/StgCmmBind.hs

@@ -68,16 +68,14 @@ cgTopRhsClosure :: Id
 		-> CostCentreStack	-- Optional cost centre annotation
 		-> StgBinderInfo
 		-> UpdateFlag
-		-> SRT
-		-> [Id]		        -- Args
+                -> [Id]                 -- Args
 		-> StgExpr
 		-> FCode CgIdInfo
 
-cgTopRhsClosure id ccs _ upd_flag srt args body = do
+cgTopRhsClosure id ccs _ upd_flag args body = do
   {	-- LAY OUT THE OBJECT
     let name = idName id
   ; lf_info <- mkClosureLFInfo id TopLevel [] upd_flag args
-  ; has_srt <- getSRTInfo srt
   ; mod_name <- getModuleName
   ; dflags   <- getDynFlags
   ; let descr         = closureDescription dflags mod_name name
@@ -86,7 +84,7 @@ cgTopRhsClosure id ccs _ upd_flag srt args body = do
     	cg_id_info    = litIdInfo id lf_info (CmmLabel closure_label)
         caffy         = idCafInfo id
         info_tbl      = mkCmmInfo closure_info -- XXX short-cut
-        closure_rep   = mkStaticClosureFields info_tbl ccs caffy has_srt []
+        closure_rep   = mkStaticClosureFields info_tbl ccs caffy []
 
   	 -- BUILD THE OBJECT, AND GENERATE INFO TABLE (IF NECESSARY)
   ; emitDataLits closure_label closure_rep

compiler/codeGen/StgCmmCon.hs

@@ -92,7 +92,6 @@ cgTopRhsCon id con args
                              info_tbl
                              dontCareCCS                -- Because it's static data
                              caffy                      -- Has CAF refs
-                             False                      -- no SRT
                              payload
 
                 -- BUILD THE OBJECT

compiler/codeGen/StgCmmExpr.hs

@@ -79,8 +79,8 @@ cgExpr (StgLetNoEscape _ _ binds expr) =
      ; cgExpr expr 
      ; emitLabel join_id}
 
-cgExpr (StgCase expr _live_vars _save_vars bndr srt alt_type alts) =
-  cgCase expr bndr srt alt_type alts
+cgExpr (StgCase expr _live_vars _save_vars bndr _srt alt_type alts) =
+  cgCase expr bndr alt_type alts
 
 cgExpr (StgLam {}) = panic "cgExpr: StgLam"
 
@@ -283,9 +283,9 @@ data GcPlan
 			-- of the case alternative(s) into the upstream check
 
 -------------------------------------
-cgCase :: StgExpr -> Id -> SRT -> AltType -> [StgAlt] -> FCode ()
+cgCase :: StgExpr -> Id -> AltType -> [StgAlt] -> FCode ()
 
-cgCase (StgOpApp (StgPrimOp op) args _) bndr _srt (AlgAlt tycon) alts
+cgCase (StgOpApp (StgPrimOp op) args _) bndr (AlgAlt tycon) alts
   | isEnumerationTyCon tycon -- Note [case on bool]
   = do { tag_expr <- do_enum_primop op args
 
@@ -360,7 +360,7 @@ would make this special case go away.
   -- code that enters the HValue, then we'll get a runtime panic, because
   -- the HValue really is a MutVar#.  The types are compatible though,
   -- so we can just generate an assignment.
-cgCase (StgApp v []) bndr _ alt_type@(PrimAlt _) alts
+cgCase (StgApp v []) bndr alt_type@(PrimAlt _) alts
   | isUnLiftedType (idType v)
   || reps_compatible
   = -- assignment suffices for unlifted types
@@ -373,7 +373,7 @@ cgCase (StgApp v []) bndr _ alt_type@(PrimAlt _) alts
   where
     reps_compatible = idPrimRep v == idPrimRep bndr
 
-cgCase scrut@(StgApp v []) _ _ (PrimAlt _) _ 
+cgCase scrut@(StgApp v []) _ (PrimAlt _) _
   = -- fail at run-time, not compile-time
     do { mb_cc <- maybeSaveCostCentre True
        ; withSequel (AssignTo [idToReg (NonVoid v)] False) (cgExpr scrut)
@@ -396,11 +396,11 @@ case a of v
 (taking advantage of the fact that the return convention for (# State#, a #)
 is the same as the return convention for just 'a')
 -}
-cgCase (StgOpApp (StgPrimOp SeqOp) [StgVarArg a, _] _) bndr srt alt_type alts
+cgCase (StgOpApp (StgPrimOp SeqOp) [StgVarArg a, _] _) bndr alt_type alts
   = -- handle seq#, same return convention as vanilla 'a'.
-    cgCase (StgApp a []) bndr srt alt_type alts
+    cgCase (StgApp a []) bndr alt_type alts
 
-cgCase scrut bndr _srt alt_type alts
+cgCase scrut bndr alt_type alts
   = -- the general case
     do { up_hp_usg <- getVirtHp        -- Upstream heap usage
        ; let ret_bndrs = chooseReturnBndrs bndr alt_type alts

compiler/codeGen/StgCmmHeap.hs

@@ -153,10 +153,9 @@ mkStaticClosureFields
         :: CmmInfoTable
         -> CostCentreStack
         -> CafInfo
-        -> Bool                 -- SRT is non-empty?
         -> [CmmLit]             -- Payload
         -> [CmmLit]             -- The full closure
-mkStaticClosureFields info_tbl ccs caf_refs has_srt payload
+mkStaticClosureFields info_tbl ccs caf_refs payload
   = mkStaticClosure info_lbl ccs payload padding
         static_link_field saved_info_field
   where
@@ -181,7 +180,7 @@ mkStaticClosureFields info_tbl ccs caf_refs has_srt payload
         | otherwise  = ASSERT(null payload) [mkIntCLit 0]
 
     static_link_field
-        | is_caf || staticClosureNeedsLink has_srt info_tbl
+        | is_caf || staticClosureNeedsLink (mayHaveCafRefs caf_refs) info_tbl
         = [static_link_value]
         | otherwise
         = []

compiler/codeGen/StgCmmUtils.hs

@@ -44,9 +44,9 @@ module StgCmmUtils (
 	mkWordCLit,
 	newStringCLit, newByteStringCLit,
 	packHalfWordsCLit,
-	blankWord,
+        blankWord,
 
-        getSRTInfo, srt_escape
+        srt_escape
   ) where
 
 #include "HsVersions.h"
@@ -66,12 +66,10 @@ import Type
 import TyCon
 import Constants
 import SMRep
-import StgSyn	( SRT(..) )
 import Module
 import Literal
 import Digraph
 import ListSetOps
-import VarSet
 import Util
 import Unique
 import DynFlags
@@ -804,19 +802,5 @@ assignTemp' e
        emitAssign reg e
        return (CmmReg reg)
 
--------------------------------------------------------------------------
---
---	Static Reference Tables
---
--------------------------------------------------------------------------
-
--- | Returns 'True' if there is a non-empty SRT, or 'False' otherwise
--- NB. the SRT attached to an StgBind is still used in the new codegen
--- to decide whether we need a static link field on a static closure
--- or not.
-getSRTInfo :: SRT -> FCode Bool
-getSRTInfo (SRTEntries vs) = return (not (isEmptyVarSet vs))
-getSRTInfo _               = return False
-
 srt_escape :: StgHalfWord
 srt_escape = -1