[project @ 2000-12-19 17:32:44 by simonpj]

[ghc-hetmet.git] / ghc / compiler / nativeGen / MachMisc.lhs

diff --git a/ghc/compiler/nativeGen/MachMisc.lhs b/ghc/compiler/nativeGen/MachMisc.lhs
index 8f5c168..7113822 100644 (file)
--- a/ghc/compiler/nativeGen/MachMisc.lhs
+++ b/ghc/compiler/nativeGen/MachMisc.lhs
@@ -50,11 +50,12 @@ import MachRegs             ( stgReg, callerSaves, RegLoc(..),
 #                         endif
                        )
 import PrimRep         ( PrimRep(..) )
-import Stix            ( StixTree(..), StixReg(..), CodeSegment )
+import Stix            ( StixTree(..), StixReg(..), CodeSegment, DestInfo(..) )
 import Panic           ( panic )
 import GlaExts         ( word2Int#, int2Word#, shiftRL#, and#, (/=#) )
 import Outputable      ( pprPanic, ppr )
 import IOExts          ( trace )
+import FastTypes
 \end{code}
 
 \begin{code}
@@ -168,11 +169,11 @@ exactLog2 x
   = if (x <= 0 || x >= 2147483648) then
        Nothing
     else
-       case (fromInteger x) of { I# x# ->
+       case iUnbox (fromInteger x) of { x# ->
        if (w2i ((i2w x#) `and#` (i2w (0# -# x#))) /=# x#) then
          Nothing
        else
-         Just (toInteger (I# (pow2 x#)))
+         Just (toInteger (iBox (pow2 x#)))
        }
   where
     shiftr x y = shiftRL# x y
@@ -283,6 +284,7 @@ primRepToSize FloatRep          = IF_ARCH_alpha( TF, IF_ARCH_i386( F, IF_ARCH_sparc(
 primRepToSize DoubleRep            = IF_ARCH_alpha( TF, IF_ARCH_i386( DF,IF_ARCH_sparc( DF,)))
 primRepToSize ArrayRep     = IF_ARCH_alpha( Q,  IF_ARCH_i386( L, IF_ARCH_sparc( W ,)))
 primRepToSize ByteArrayRep  = IF_ARCH_alpha( Q,         IF_ARCH_i386( L, IF_ARCH_sparc( W ,)))
+primRepToSize PrimPtrRep    = IF_ARCH_alpha( Q,         IF_ARCH_i386( L, IF_ARCH_sparc( W ,)))
 primRepToSize WeakPtrRep    = IF_ARCH_alpha( Q,         IF_ARCH_i386( L, IF_ARCH_sparc( W ,)))
 primRepToSize ForeignObjRep = IF_ARCH_alpha( Q,  IF_ARCH_i386( L, IF_ARCH_sparc( W ,)))
 primRepToSize BCORep        = IF_ARCH_alpha( Q,  IF_ARCH_i386( L, IF_ARCH_sparc( W ,)))
@@ -436,6 +438,15 @@ We might as well make use of whatever unique FP facilities Intel have
 chosen to bless us with (let's not be churlish, after all).
 Hence GLDZ and GLD1.  Bwahahahahahahaha!
 
+LATER (10 Nov 2000): idiv gives problems with the register spiller,
+because the spiller is simpleminded and because idiv has fixed uses of
+%eax and %edx.  Rather than make the spiller cleverer, we do away with
+idiv, and instead have iquot and irem fake (integer) insns, which have
+no operand register constraints -- ie, they behave like add, sub, mul.
+The printer-outer transforms them to a sequence of real insns which does
+the Right Thing (tm).  As with the FP stuff, this gives ropey code, 
+but we don't care, since it doesn't get used much.  We hope.
+
 \begin{code}
 #if i386_TARGET_ARCH
 
@@ -455,12 +466,14 @@ Hence GLDZ and GLD1.  Bwahahahahahahaha!
 
              | ADD           Size Operand Operand
              | SUB           Size Operand Operand
+             | IMUL          Size Operand Operand
 
--- Multiplication (signed and unsigned), Division (signed and unsigned),
--- result in %eax, %edx.
+-- Quotient and remainder.  SEE comment above -- these are not
+-- real x86 insns; instead they are expanded when printed
+-- into a sequence of real insns.
 
-             | IMUL          Size Operand Operand
-             | IDIV          Size Operand
+              | IQUOT         Size Operand Operand
+              | IREM          Size Operand Operand
 
 -- Simple bit-twiddling.
 
@@ -529,7 +542,7 @@ Hence GLDZ and GLD1.  Bwahahahahahahaha!
 
 -- Jumping around.
 
-             | JMP           Operand -- target
+             | JMP           DestInfo Operand -- possible dests, target
              | JXX           Cond CLabel -- target
              | CALL          Imm
 
@@ -552,10 +565,14 @@ i386_insert_ffrees insns
 
 ffree_before_nonlocal_transfers insn
    = case insn of
-        CALL _                                      -> [GFREE, insn]
-        JMP (OpImm (ImmCLbl clbl)) | isAsmTemp clbl -> [insn]
-        JMP _                                       -> [GFREE, insn]
-        other                                       -> [insn]
+        CALL _                                        -> [GFREE, insn]
+        -- Jumps to immediate labels are local
+        JMP _ (OpImm (ImmCLbl clbl)) | isAsmTemp clbl -> [insn]
+        -- If a jump mentions dests, it is a local jump thru
+        -- a case table.
+        JMP (DestInfo _) _                            -> [insn]
+        JMP _ _                                       -> [GFREE, insn]
+        other                                         -> [insn]
 
 
 -- if you ever add a new FP insn to the fake x86 FP insn set,
@@ -629,7 +646,7 @@ is_G_instr instr
              | BI            Cond Bool Imm -- cond, annul?, target
              | BF            Cond Bool Imm -- cond, annul?, target
 
-             | JMP           MachRegsAddr      -- target
+             | JMP           DestInfo MachRegsAddr      -- target
              | CALL          Imm Int Bool -- target, args, terminal
 
 data RI = RIReg Reg