[project @ 1999-01-14 17:58:41 by sof]

Assorted minor Haskell 98 changes:

  * Maximal munch rule for "--" comments
  * _ as lower-case letter, "_" is a reserved id. Prefixing unused
    variable names in patterns with '_' causes the renamer not to
    report such names as being unused.
  * allow empty decls
  * comprehensions are now list comprehensions, not monadic.
  * use Monad.fail to signal pattern matching errors within
    do expressions.
  * remove record punning.
  * empty contexts are now legal  (go wild!)
  * allow records with no fields
  * allow newtypes with a labelled field
  * default default is now (Integer, Double)
  * turn off defaulting mechanism for args & res to a _ccall_.
  * allow LHSs of the form  (a -.- b) x = ...
  * Main.main can now have type (IO a)
  * nuked Void (and its use in the compiler sources.)
  * deriving machinery for Enum now also generate 'succ' and 'pred'
    method bindings.

1 files changed, 26 insertions, 11 deletions

diff --git a/ghc/compiler/codeGen/CgExpr.lhs b/ghc/compiler/codeGen/CgExpr.lhs
index 3cc58a675d..ddf179dffe 100644
--- a/ghc/compiler/codeGen/CgExpr.lhs
+++ b/ghc/compiler/codeGen/CgExpr.lhs
@@ -1,7 +1,7 @@
 %
 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
 %
-% $Id: CgExpr.lhs,v 1.18 1998/12/22 12:55:55 simonm Exp $
+% $Id: CgExpr.lhs,v 1.19 1999/01/14 17:58:46 sof Exp $
 %
 %********************************************************
 %*							*
@@ -18,6 +18,7 @@ import Constants	( mAX_SPEC_SELECTEE_SIZE, mAX_SPEC_AP_SIZE )
 import StgSyn
 import CgMonad
 import AbsCSyn
+import AbsCUtils	( mkAbstractCs )
 import CLabel		( mkClosureTblLabel )
 
 import SMRep		( fixedHdrSize )
@@ -423,15 +424,29 @@ Little helper for primitives that return unboxed tuples.
 \begin{code}
 primRetUnboxedTuple :: PrimOp -> [StgArg] -> Type -> Code
 primRetUnboxedTuple op args res_ty
-  = let (tc,ty_args) = case splitTyConAppThroughNewTypes res_ty of
-			  Nothing -> pprPanic "primRetUnboxedTuple" (ppr res_ty)
-			  Just pr -> pr
-
-	prim_reps         = map typePrimRep ty_args
-	temp_uniqs        = map mkBuiltinUnique [0..length ty_args]
-	temp_amodes       = zipWith CTemp temp_uniqs prim_reps
+  = getArgAmodes args	    `thenFC` \ arg_amodes ->
+    {-
+      put all the arguments in temporaries so they don't get stomped when
+      we push the return address.
+    -}
+    let
+      n_args		  = length args
+      arg_uniqs	          = map mkBuiltinUnique [0 .. n_args-1]
+      arg_reps		  = map getArgPrimRep args
+      arg_temps		  = zipWith CTemp arg_uniqs arg_reps
+    in
+    absC (mkAbstractCs (zipWith CAssign arg_temps arg_amodes)) `thenC`
+    {-
+      allocate some temporaries for the return values.
+    -}
+    let
+      (tc,ty_args)      = case splitTyConAppThroughNewTypes res_ty of
+			    Nothing -> pprPanic "primRetUnboxedTuple" (ppr res_ty)
+			    Just pr -> pr
+      prim_reps          = map typePrimRep ty_args
+      temp_uniqs         = map mkBuiltinUnique [ n_args .. n_args + length ty_args - 1]
+      temp_amodes        = zipWith CTemp temp_uniqs prim_reps
     in
-    returnUnboxedTuple temp_amodes 
-	(getArgAmodes args  `thenFC` \ arg_amodes ->		
-	 absC (COpStmt temp_amodes op arg_amodes []))
+    returnUnboxedTuple temp_amodes (absC (COpStmt temp_amodes op arg_temps []))
+
 \end{code}