X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fprelude%2Fprimops.txt.pp;h=adb2e110ff8ced4fc4348f767daa93185a37c4bf;hb=6ee9554a738c442719ded861504acb729fd3d431;hp=13ce30232a2330f587041ed772f5698c1d94f8c1;hpb=87c631be70d0a6d29b621f9a46b8d465c275ad86;p=ghc-hetmet.git

diff --git a/compiler/prelude/primops.txt.pp b/compiler/prelude/primops.txt.pp
index 13ce302..adb2e11 100644
--- a/compiler/prelude/primops.txt.pp
+++ b/compiler/prelude/primops.txt.pp
@@ -545,6 +545,10 @@ primop   DoubleDivOp   "/##"   Dyadic
 primop   DoubleNegOp   "negateDouble#"  Monadic   Double# -> Double#
 
 primop   Double2IntOp   "double2Int#"          GenPrimOp  Double# -> Int#
+   {Truncates a {\tt Double#} value to the nearest {\tt Int#}.
+    Results are undefined if the truncation if truncation yields
+    a value outside the range of {\tt Int#}.}
+
 primop   Double2FloatOp   "double2Float#" GenPrimOp Double# -> Float#
 
 primop   DoubleExpOp   "expDouble#"      Monadic
@@ -614,6 +618,13 @@ primop   DoubleDecodeOp   "decodeDouble#" GenPrimOp
     represent an {\tt Integer\#} holding the mantissa.}
    with out_of_line = True
 
+primop   DoubleDecode_2IntOp   "decodeDouble_2Int#" GenPrimOp    
+   Double# -> (# Int#, Int#, Int# #)
+   {Convert to arbitrary-precision integer.
+    First {\tt Int\#} in result is the high 32 bits of the mantissa, and the
+    second is the low 32. The third is the exponent.}
+   with out_of_line = True
+
 ------------------------------------------------------------------------
 section "Float#" 
 	{Operations on single-precision (32-bit) floating-point numbers.}
@@ -652,6 +663,9 @@ primop   FloatDivOp   "divideFloat#"      Dyadic
 primop   FloatNegOp   "negateFloat#"      Monadic    Float# -> Float#
 
 primop   Float2IntOp   "float2Int#"      GenPrimOp  Float# -> Int#
+   {Truncates a {\tt Float#} value to the nearest {\tt Int#}.
+    Results are undefined if the truncation if truncation yields
+    a value outside the range of {\tt Int#}.}
 
 primop   FloatExpOp   "expFloat#"      Monadic          
    Float# -> Float#
@@ -717,6 +731,12 @@ primop   FloatDecodeOp   "decodeFloat#" GenPrimOp
     represent an {\tt Integer\#} holding the mantissa.}
    with out_of_line = True
 
+primop   FloatDecode_IntOp   "decodeFloat_Int#" GenPrimOp
+   Float# -> (# Int#, Int# #)
+   {Convert to arbitrary-precision integer.
+    First {\tt Int\#} in result is the mantissa; second is the exponent.}
+   with out_of_line = True
+
 ------------------------------------------------------------------------
 section "Arrays"
 	{Operations on {\tt Array\#}.}
@@ -1233,7 +1253,7 @@ primop  CatchOp "catch#" GenPrimOp
 primop  RaiseOp "raise#" GenPrimOp
    a -> b
    with
-   strictness  = { \ arity -> mkStrictSig (mkTopDmdType [lazyDmd] BotRes) }
+   strictness  = { \ _arity -> mkStrictSig (mkTopDmdType [lazyDmd] BotRes) }
       -- NB: result is bottom
    out_of_line = True
 
@@ -1653,7 +1673,7 @@ section "Tag to enum stuff"
 primop  DataToTagOp "dataToTag#" GenPrimOp
    a -> Int#
    with
-   strictness  = { \ arity -> mkStrictSig (mkTopDmdType [seqDmd] TopRes) }
+   strictness  = { \ _arity -> mkStrictSig (mkTopDmdType [seqDmd] TopRes) }
 	-- dataToTag# must have an evaluated argument
 
 primop  TagToEnumOp "tagToEnum#" GenPrimOp     
@@ -1788,7 +1808,14 @@ pseudoop   "unsafeCoerce#"
            known to be empty.  Also, a {\tt newtype} of a type {\tt T} has the same representation
            at runtime as {\tt T}.
 
-        Other uses of {\tt unsafeCoerce\#} are undefined.
+        Other uses of {\tt unsafeCoerce\#} are undefined.  In particular, you should not use
+	{\tt unsafeCoerce\#} to cast a T to an algebraic data type D, unless T is also
+	an algebraic data type.  For example, do not cast {\tt Int->Int} to {\tt Bool}, even if
+        you later cast that {\tt Bool} back to {\tt Int->Int} before applying it.  The reasons
+        have to do with GHC's internal representation details (for the congnoscenti, data values
+	can be entered but function closures cannot).  If you want a safe type to cast things
+	to, use {\tt Any}, which is not an algebraic data type.
+	
         }
 
 -- NB. It is tempting to think that casting a value to a type that it doesn't have is safe