Let LLVM and C handle > native size arithmeticwip/llvm-big-prim

NCG needs to call slow FFI functions where we "borrow" the C compiler's
implementation, but there is no reason why we need to do that for LLVM,
or the unregisterized backend where everything is via C anyways!

3 files changed, 67 insertions, 60 deletions

diff --git a/compiler/GHC/CmmToC.hs b/compiler/GHC/CmmToC.hs
index 3008f01c5c..e259cdb55d 100644
--- a/compiler/GHC/CmmToC.hs
+++ b/compiler/GHC/CmmToC.hs
@@ -860,40 +860,43 @@ pprCallishMachOp_for_C mop
         MO_SubIntC    {} -> unsupported
         MO_U_Mul2     {} -> unsupported
         MO_Touch         -> unsupported
+        -- we could support prefetch via "__builtin_prefetch"
+        -- Not adding it for now
         (MO_Prefetch_Data _ ) -> unsupported
-        --- we could support prefetch via "__builtin_prefetch"
-        --- Not adding it for now
-        MO_I64_ToI   -> text "hs_int64ToInt"
-        MO_I64_FromI -> text "hs_intToInt64"
-        MO_W64_ToW   -> text "hs_word64ToWord"
-        MO_W64_FromW -> text "hs_wordToWord64"
-        MO_x64_Neg   -> text "hs_neg64"
-        MO_x64_Add   -> text "hs_add64"
-        MO_x64_Sub   -> text "hs_sub64"
-        MO_x64_Mul   -> text "hs_mul64"
-        MO_I64_Quot  -> text "hs_quotInt64"
-        MO_I64_Rem   -> text "hs_remInt64"
-        MO_W64_Quot  -> text "hs_quotWord64"
-        MO_W64_Rem   -> text "hs_remWord64"
-        MO_x64_And   -> text "hs_and64"
-        MO_x64_Or    -> text "hs_xor64"
-        MO_x64_Xor   -> text "hs_xor64"
-        MO_x64_Not   -> text "hs_not64"
-        MO_x64_Shl   -> text "hs_uncheckedShiftL64"
-        MO_I64_Shr   -> text "hs_uncheckedIShiftRA64"
-        MO_W64_Shr   -> text "hs_uncheckedShiftRL64"
-        MO_x64_Eq    -> text "hs_eq64"
-        MO_x64_Ne    -> text "hs_ne64"
-        MO_I64_Ge    -> text "hs_geInt64"
-        MO_I64_Gt    -> text "hs_gtInt64"
-        MO_I64_Le    -> text "hs_leInt64"
-        MO_I64_Lt    -> text "hs_ltInt64"
-        MO_W64_Ge    -> text "hs_geWord64"
-        MO_W64_Gt    -> text "hs_gtWord64"
-        MO_W64_Le    -> text "hs_leWord64"
-        MO_W64_Lt    -> text "hs_ltWord64"
+
+        MO_I64_ToI   -> dontReach64
+        MO_I64_FromI -> dontReach64
+        MO_W64_ToW   -> dontReach64
+        MO_W64_FromW -> dontReach64
+        MO_x64_Neg   -> dontReach64
+        MO_x64_Add   -> dontReach64
+        MO_x64_Sub   -> dontReach64
+        MO_x64_Mul   -> dontReach64
+        MO_I64_Quot  -> dontReach64
+        MO_I64_Rem   -> dontReach64
+        MO_W64_Quot  -> dontReach64
+        MO_W64_Rem   -> dontReach64
+        MO_x64_And   -> dontReach64
+        MO_x64_Or    -> dontReach64
+        MO_x64_Xor   -> dontReach64
+        MO_x64_Not   -> dontReach64
+        MO_x64_Shl   -> dontReach64
+        MO_I64_Shr   -> dontReach64
+        MO_W64_Shr   -> dontReach64
+        MO_x64_Eq    -> dontReach64
+        MO_x64_Ne    -> dontReach64
+        MO_I64_Ge    -> dontReach64
+        MO_I64_Gt    -> dontReach64
+        MO_I64_Le    -> dontReach64
+        MO_I64_Lt    -> dontReach64
+        MO_W64_Ge    -> dontReach64
+        MO_W64_Gt    -> dontReach64
+        MO_W64_Le    -> dontReach64
+        MO_W64_Lt    -> dontReach64
     where unsupported = panic ("pprCallishMachOp_for_C: " ++ show mop
                             ++ " not supported!")
+          dontReach64 = panic ("pprCallishMachOp_for_C: " ++ show mop
+                            ++ " should be not be encountered because the regular primop for this 64-bit operation is used instead.")
 
 -- ---------------------------------------------------------------------
 -- Useful #defines
diff --git a/compiler/GHC/CmmToLlvm/CodeGen.hs b/compiler/GHC/CmmToLlvm/CodeGen.hs
index dd2779ef71..b10b26d416 100644
--- a/compiler/GHC/CmmToLlvm/CodeGen.hs
+++ b/compiler/GHC/CmmToLlvm/CodeGen.hs
@@ -807,6 +807,8 @@ cmmPrimOpFunctions mop = do
       intrinTy2 = "p0i8." ++ showSDoc dflags (ppr $ llvmWord platform)
       unsupported = panic ("cmmPrimOpFunctions: " ++ show mop
                         ++ " not supported here")
+      dontReach64 = panic ("cmmPrimOpFunctions: " ++ show mop
+                        ++ " should be not be encountered because the regular primop for this 64-bit operation is used instead.")
 
   return $ case mop of
     MO_F32_Exp    -> fsLit "expf"
@@ -911,35 +913,35 @@ cmmPrimOpFunctions mop = do
     MO_Cmpxchg _     -> unsupported
     MO_Xchg _        -> unsupported
 
-    MO_I64_ToI       -> fsLit "hs_int64ToInt"
-    MO_I64_FromI     -> fsLit "hs_intToInt64"
-    MO_W64_ToW       -> fsLit "hs_word64ToWord"
-    MO_W64_FromW     -> fsLit "hs_wordToWord64"
-    MO_x64_Neg       -> fsLit "hs_neg64"
-    MO_x64_Add       -> fsLit "hs_add64"
-    MO_x64_Sub       -> fsLit "hs_sub64"
-    MO_x64_Mul       -> fsLit "hs_mul64"
-    MO_I64_Quot      -> fsLit "hs_quotInt64"
-    MO_I64_Rem       -> fsLit "hs_remInt64"
-    MO_W64_Quot      -> fsLit "hs_quotWord64"
-    MO_W64_Rem       -> fsLit "hs_remWord64"
-    MO_x64_And       -> fsLit "hs_and64"
-    MO_x64_Or        -> fsLit "hs_or64"
-    MO_x64_Xor       -> fsLit "hs_xor64"
-    MO_x64_Not       -> fsLit "hs_not64"
-    MO_x64_Shl       -> fsLit "hs_uncheckedShiftL64"
-    MO_I64_Shr       -> fsLit "hs_uncheckedIShiftRA64"
-    MO_W64_Shr       -> fsLit "hs_uncheckedShiftRL64"
-    MO_x64_Eq        -> fsLit "hs_eq64"
-    MO_x64_Ne        -> fsLit "hs_ne64"
-    MO_I64_Ge        -> fsLit "hs_geInt64"
-    MO_I64_Gt        -> fsLit "hs_gtInt64"
-    MO_I64_Le        -> fsLit "hs_leInt64"
-    MO_I64_Lt        -> fsLit "hs_ltInt64"
-    MO_W64_Ge        -> fsLit "hs_geWord64"
-    MO_W64_Gt        -> fsLit "hs_gtWord64"
-    MO_W64_Le        -> fsLit "hs_leWord64"
-    MO_W64_Lt        -> fsLit "hs_ltWord64"
+    MO_I64_ToI       -> dontReach64
+    MO_I64_FromI     -> dontReach64
+    MO_W64_ToW       -> dontReach64
+    MO_W64_FromW     -> dontReach64
+    MO_x64_Neg       -> dontReach64
+    MO_x64_Add       -> dontReach64
+    MO_x64_Sub       -> dontReach64
+    MO_x64_Mul       -> dontReach64
+    MO_I64_Quot      -> dontReach64
+    MO_I64_Rem       -> dontReach64
+    MO_W64_Quot      -> dontReach64
+    MO_W64_Rem       -> dontReach64
+    MO_x64_And       -> dontReach64
+    MO_x64_Or        -> dontReach64
+    MO_x64_Xor       -> dontReach64
+    MO_x64_Not       -> dontReach64
+    MO_x64_Shl       -> dontReach64
+    MO_I64_Shr       -> dontReach64
+    MO_W64_Shr       -> dontReach64
+    MO_x64_Eq        -> dontReach64
+    MO_x64_Ne        -> dontReach64
+    MO_I64_Ge        -> dontReach64
+    MO_I64_Gt        -> dontReach64
+    MO_I64_Le        -> dontReach64
+    MO_I64_Lt        -> dontReach64
+    MO_W64_Ge        -> dontReach64
+    MO_W64_Gt        -> dontReach64
+    MO_W64_Le        -> dontReach64
+    MO_W64_Lt        -> dontReach64
 
 
 -- | Tail function calls
diff --git a/compiler/GHC/StgToCmm/Prim.hs b/compiler/GHC/StgToCmm/Prim.hs
index ab1ac89576..dff86341b1 100644
--- a/compiler/GHC/StgToCmm/Prim.hs
+++ b/compiler/GHC/StgToCmm/Prim.hs
@@ -1707,6 +1707,8 @@ emitPrimOp dflags primop = case primop of
     -> PrimopCmmEmit
   opTranslate64 args mkMop callish =
     case platformWordSize platform of
+      -- LLVM and C `can handle larger than native size arithmetic natively.
+      _ | not ncg -> opTranslate args $ mkMop W64
       PW4 -> opCallish args callish
       PW8 -> opTranslate args $ mkMop W64