Implement -X=GADTs and -X=RelaxedPolyRec

[ghc-hetmet.git] / compiler / nativeGen / MachCodeGen.hs

diff --git a/compiler/nativeGen/MachCodeGen.hs b/compiler/nativeGen/MachCodeGen.hs
index fca5be3..79c8d69 100644 (file)
--- a/compiler/nativeGen/MachCodeGen.hs
+++ b/compiler/nativeGen/MachCodeGen.hs
@@ -1148,16 +1148,30 @@ getRegister e@(CmmMachOp mop [x, y]) -- dyadic MachOps
          -- in
          return (Any rep code)
         
-    {- Case2: shift length is complex (non-immediate) -}
+    {- Case2: shift length is complex (non-immediate)
+      * y must go in %ecx.
+      * we cannot do y first *and* put its result in %ecx, because
+        %ecx might be clobbered by x.
+      * if we do y second, then x cannot be 
+        in a clobbered reg.  Also, we cannot clobber x's reg
+        with the instruction itself.
+      * so we can either:
+        - do y first, put its result in a fresh tmp, then copy it to %ecx later
+        - do y second and put its result into %ecx.  x gets placed in a fresh
+          tmp.  This is likely to be better, becuase the reg alloc can
+          eliminate this reg->reg move here (it won't eliminate the other one,
+          because the move is into the fixed %ecx).
+    -}
     shift_code rep instr x y{-amount-} = do
-        (x_reg, x_code) <- getNonClobberedReg x
+        x_code <- getAnyReg x
+       tmp <- getNewRegNat rep
         y_code <- getAnyReg y
        let 
-          code = x_code `appOL`
+          code = x_code tmp `appOL`
                  y_code ecx `snocOL`
-                 instr (OpReg ecx) (OpReg x_reg)
+                 instr (OpReg ecx) (OpReg tmp)
         -- in
-        return (Fixed rep x_reg code)
+        return (Fixed rep tmp code)
 
     --------------------
     add_code :: MachRep -> CmmExpr -> CmmExpr -> NatM Register
@@ -1839,6 +1853,9 @@ getAmode (CmmMachOp (MO_Add rep)
   && not (is64BitInteger offset)
   = x86_complex_amode x y shift offset
 
+getAmode (CmmMachOp (MO_Add rep) [x,y])
+  = x86_complex_amode x y 0 0
+
 getAmode (CmmLit lit) | not (is64BitLit lit)
   = return (Amode (ImmAddr (litToImm lit) 0) nilOL)
 
@@ -2378,6 +2395,25 @@ assignIntCode pk dst src
 #if i386_TARGET_ARCH || x86_64_TARGET_ARCH
 
 -- integer assignment to memory
+
+-- specific case of adding/subtracting an integer to a particular address.
+-- ToDo: catch other cases where we can use an operation directly on a memory 
+-- address.
+assignMem_IntCode pk addr (CmmMachOp op [CmmLoad addr2 _,
+                                                 CmmLit (CmmInt i _)])
+   | addr == addr2, pk /= I64 || not (is64BitInteger i),
+     Just instr <- check op
+   = do Amode amode code_addr <- getAmode addr
+        let code = code_addr `snocOL`
+                   instr pk (OpImm (ImmInt (fromIntegral i))) (OpAddr amode)
+        return code
+   where
+        check (MO_Add _) = Just ADD
+        check (MO_Sub _) = Just SUB
+        check _ = Nothing
+        -- ToDo: more?
+
+-- general case
 assignMem_IntCode pk addr src = do
     Amode addr code_addr <- getAmode addr
     (code_src, op_src)   <- get_op_RI src
@@ -3325,10 +3361,10 @@ genCCall target dest_regs args vols = do
         (arg_reg, arg_code) <- getSomeReg arg
          delta <- getDeltaNat
          setDeltaNat (delta-arg_size)
-        let code' = code `appOL` toOL [
-                       MOV arg_rep (OpReg arg_reg) (OpAddr  (spRel 0)),
+        let code' = code `appOL` arg_code `appOL` toOL [
                        SUB wordRep (OpImm (ImmInt arg_size)) (OpReg rsp) ,
-                       DELTA (delta-arg_size)]
+                       DELTA (delta-arg_size),
+                       MOV arg_rep (OpReg arg_reg) (OpAddr  (spRel 0))]
         push_args rest code'
 
        | otherwise = do
@@ -4541,6 +4577,8 @@ remainderCode rep div x y = do
 -- -----------------------------------------------------------------------------
 --  Coercing to/from integer/floating-point...
 
+-- When going to integer, we truncate (round towards 0).
+
 -- @coerce(Int2FP|FP2Int)@ are more complicated integer/float
 -- conversions.  We have to store temporaries in memory to move
 -- between the integer and the floating point register sets.
@@ -4626,7 +4664,7 @@ coerceFP2Int from to x = do
 coerceFP2Int from to x = do
   (x_op, x_code) <- getOperand x  -- ToDo: could be a safe operand
   let
-        opc  = case from of F32 -> CVTSS2SI; F64 -> CVTSD2SI
+        opc  = case from of F32 -> CVTTSS2SIQ; F64 -> CVTTSD2SIQ
         code dst = x_code `snocOL` opc x_op dst
   -- in
   return (Any to code) -- works even if the destination rep is <I32