-----------------------------------------------------------------------------
--
-- Pretty-printing assembly language
--
-- (c) The University of Glasgow 1993-2005
--
-----------------------------------------------------------------------------

module X86.Ppr (
	pprNatCmmTop,
	pprBasicBlock,
	pprSectionHeader,
	pprData,
	pprInstr,
	pprUserReg,
	pprSize,
	pprImm,
	pprDataItem,
)

where

#include "HsVersions.h"
#include "nativeGen/NCG.h"

import X86.Regs
import X86.Instr
import X86.Cond
import Instruction
import Size
import Reg
import PprBase


import BlockId
import Cmm
import CLabel
import Unique		( pprUnique )
import Pretty
import FastString
import qualified Outputable
import Outputable	(panic, Outputable)

import Data.Word

#if i386_TARGET_ARCH && darwin_TARGET_OS
import Data.Bits
#endif

-- -----------------------------------------------------------------------------
-- Printing this stuff out

pprNatCmmTop :: NatCmmTop Instr -> Doc
pprNatCmmTop (CmmData section dats) = 
  pprSectionHeader section $$ vcat (map pprData dats)

 -- special case for split markers:
pprNatCmmTop (CmmProc [] lbl _ (ListGraph [])) = pprLabel lbl

pprNatCmmTop (CmmProc info lbl _ (ListGraph blocks)) = 
  pprSectionHeader Text $$
  (if null info then -- blocks guaranteed not null, so label needed
       pprLabel lbl
   else
#if HAVE_SUBSECTIONS_VIA_SYMBOLS
            pprCLabel_asm (mkDeadStripPreventer $ entryLblToInfoLbl lbl)
                <> char ':' $$
#endif
       vcat (map pprData info) $$
       pprLabel (entryLblToInfoLbl lbl)
  ) $$
  vcat (map pprBasicBlock blocks)
     -- above: Even the first block gets a label, because with branch-chain
     -- elimination, it might be the target of a goto.
#if HAVE_SUBSECTIONS_VIA_SYMBOLS
        -- If we are using the .subsections_via_symbols directive
        -- (available on recent versions of Darwin),
        -- we have to make sure that there is some kind of reference
        -- from the entry code to a label on the _top_ of of the info table,
        -- so that the linker will not think it is unreferenced and dead-strip
        -- it. That's why the label is called a DeadStripPreventer (_dsp).
  $$ if not (null info)
		    then text "\t.long "
		      <+> pprCLabel_asm (entryLblToInfoLbl lbl)
		      <+> char '-'
		      <+> pprCLabel_asm (mkDeadStripPreventer $ entryLblToInfoLbl lbl)
		    else empty
#endif


pprBasicBlock :: NatBasicBlock Instr -> Doc
pprBasicBlock (BasicBlock (BlockId id) instrs) =
  pprLabel (mkAsmTempLabel id) $$
  vcat (map pprInstr instrs)


pprData :: CmmStatic -> Doc
pprData (CmmAlign bytes)         = pprAlign bytes
pprData (CmmDataLabel lbl)       = pprLabel lbl
pprData (CmmString str)          = pprASCII str

#if  darwin_TARGET_OS
pprData (CmmUninitialised bytes) = ptext (sLit ".space ") <> int bytes
#else
pprData (CmmUninitialised bytes) = ptext (sLit ".skip ") <> int bytes
#endif

pprData (CmmStaticLit lit)       = pprDataItem lit

pprGloblDecl :: CLabel -> Doc
pprGloblDecl lbl
  | not (externallyVisibleCLabel lbl) = empty
  | otherwise = ptext IF_ARCH_sparc((sLit ".global "), 
				    (sLit ".globl ")) <>
		pprCLabel_asm lbl

pprTypeAndSizeDecl :: CLabel -> Doc
#if elf_OBJ_FORMAT
pprTypeAndSizeDecl lbl
  | not (externallyVisibleCLabel lbl) = empty
  | otherwise = ptext (sLit ".type ") <>
		pprCLabel_asm lbl <> ptext (sLit ", @object")
#else
pprTypeAndSizeDecl _
  = empty
#endif

pprLabel :: CLabel -> Doc
pprLabel lbl = pprGloblDecl lbl $$ pprTypeAndSizeDecl lbl $$ (pprCLabel_asm lbl <> char ':')


pprASCII :: [Word8] -> Doc
pprASCII str
  = vcat (map do1 str) $$ do1 0
    where
       do1 :: Word8 -> Doc
       do1 w = ptext (sLit "\t.byte\t") <> int (fromIntegral w)

pprAlign :: Int -> Doc


pprAlign bytes
	= ptext (sLit ".align ") <> int IF_OS_darwin(pow2, bytes)
  where

#if darwin_TARGET_OS
	pow2 = log2 bytes

	log2 :: Int -> Int  -- cache the common ones
	log2 1 = 0 
	log2 2 = 1
	log2 4 = 2
	log2 8 = 3
	log2 n = 1 + log2 (n `quot` 2)
#endif

-- -----------------------------------------------------------------------------
-- pprInstr: print an 'Instr'

instance Outputable Instr where
    ppr	 instr	= Outputable.docToSDoc $ pprInstr instr


#if  i386_TARGET_ARCH || x86_64_TARGET_ARCH
pprUserReg :: Reg -> Doc
pprUserReg = pprReg IF_ARCH_i386(II32,) IF_ARCH_x86_64(II64,)

#else
pprUserReg :: Reg -> Doc
pprUserReg = panic "X86.Ppr.pprUserReg: not defined"

#endif

pprReg :: Size -> Reg -> Doc

pprReg s r
  = case r of
      RegReal    (RealRegSingle i) -> ppr_reg_no s i
      RegReal    (RealRegPair _ _) -> panic "X86.Ppr: no reg pairs on this arch"
      RegVirtual (VirtualRegI  u)  -> text "%vI_" <> asmSDoc (pprUnique u)
      RegVirtual (VirtualRegHi u)  -> text "%vHi_" <> asmSDoc (pprUnique u)
      RegVirtual (VirtualRegF  u)  -> text "%vF_" <> asmSDoc (pprUnique u)
      RegVirtual (VirtualRegD  u)  -> text "%vD_" <> asmSDoc (pprUnique u)
  where
#if i386_TARGET_ARCH
    ppr_reg_no :: Size -> Int -> Doc
    ppr_reg_no II8   = ppr_reg_byte
    ppr_reg_no II16  = ppr_reg_word
    ppr_reg_no _    = ppr_reg_long

    ppr_reg_byte i = ptext
      (case i of {
	 0 -> sLit "%al";     1 -> sLit "%bl";
	 2 -> sLit "%cl";     3 -> sLit "%dl";
	_  -> sLit "very naughty I386 byte register"
      })

    ppr_reg_word i = ptext
      (case i of {
	 0 -> sLit "%ax";     1 -> sLit "%bx";
	 2 -> sLit "%cx";     3 -> sLit "%dx";
	 4 -> sLit "%si";     5 -> sLit "%di";
	 6 -> sLit "%bp";     7 -> sLit "%sp";
	_  -> sLit "very naughty I386 word register"
      })

    ppr_reg_long i = ptext
      (case i of {
	 0 -> sLit "%eax";    1 -> sLit "%ebx";
	 2 -> sLit "%ecx";    3 -> sLit "%edx";
	 4 -> sLit "%esi";    5 -> sLit "%edi";
	 6 -> sLit "%ebp";    7 -> sLit "%esp";
	 8 -> sLit "%fake0";  9 -> sLit "%fake1";
	10 -> sLit "%fake2"; 11 -> sLit "%fake3";
	12 -> sLit "%fake4"; 13 -> sLit "%fake5";
	_  -> sLit "very naughty I386 register"
      })
#elif x86_64_TARGET_ARCH
    ppr_reg_no :: Size -> Int -> Doc
    ppr_reg_no II8   = ppr_reg_byte
    ppr_reg_no II16  = ppr_reg_word
    ppr_reg_no II32  = ppr_reg_long
    ppr_reg_no _    = ppr_reg_quad

    ppr_reg_byte i = ptext
      (case i of {
	 0 -> sLit "%al";     1 -> sLit "%bl";
	 2 -> sLit "%cl";     3 -> sLit "%dl";
	 4 -> sLit "%sil";    5 -> sLit "%dil"; -- new 8-bit regs!
	 6 -> sLit "%bpl";    7 -> sLit "%spl";
	 8 -> sLit "%r8b";    9  -> sLit "%r9b";
	10 -> sLit "%r10b";   11 -> sLit "%r11b";
	12 -> sLit "%r12b";   13 -> sLit "%r13b";
	14 -> sLit "%r14b";   15 -> sLit "%r15b";
	_  -> sLit "very naughty x86_64 byte register"
      })

    ppr_reg_word i = ptext
      (case i of {
	 0 -> sLit "%ax";     1 -> sLit "%bx";
	 2 -> sLit "%cx";     3 -> sLit "%dx";
	 4 -> sLit "%si";     5 -> sLit "%di";
	 6 -> sLit "%bp";     7 -> sLit "%sp";
	 8 -> sLit "%r8w";    9  -> sLit "%r9w";
	10 -> sLit "%r10w";   11 -> sLit "%r11w";
	12 -> sLit "%r12w";   13 -> sLit "%r13w";
	14 -> sLit "%r14w";   15 -> sLit "%r15w";
	_  -> sLit "very naughty x86_64 word register"
      })

    ppr_reg_long i = ptext
      (case i of {
	 0 -> sLit "%eax";    1  -> sLit "%ebx";
	 2 -> sLit "%ecx";    3  -> sLit "%edx";
	 4 -> sLit "%esi";    5  -> sLit "%edi";
	 6 -> sLit "%ebp";    7  -> sLit "%esp";
	 8 -> sLit "%r8d";    9  -> sLit "%r9d";
	10 -> sLit "%r10d";   11 -> sLit "%r11d";
	12 -> sLit "%r12d";   13 -> sLit "%r13d";
	14 -> sLit "%r14d";   15 -> sLit "%r15d";
	_  -> sLit "very naughty x86_64 register"
      })

    ppr_reg_quad i = ptext
      (case i of {
	 0 -> sLit "%rax";	1 -> sLit "%rbx";
	 2 -> sLit "%rcx";	3 -> sLit "%rdx";
	 4 -> sLit "%rsi";	5 -> sLit "%rdi";
	 6 -> sLit "%rbp";	7 -> sLit "%rsp";
	 8 -> sLit "%r8";  	9 -> sLit "%r9";
	10 -> sLit "%r10";    11 -> sLit "%r11";
	12 -> sLit "%r12";    13 -> sLit "%r13";
	14 -> sLit "%r14";    15 -> sLit "%r15";
	16 -> sLit "%xmm0";   17 -> sLit "%xmm1";
	18 -> sLit "%xmm2";   19 -> sLit "%xmm3";
	20 -> sLit "%xmm4";   21 -> sLit "%xmm5";
	22 -> sLit "%xmm6";   23 -> sLit "%xmm7";
	24 -> sLit "%xmm8";   25 -> sLit "%xmm9";
	26 -> sLit "%xmm10";  27 -> sLit "%xmm11";
	28 -> sLit "%xmm12";  29 -> sLit "%xmm13";
	30 -> sLit "%xmm14";  31 -> sLit "%xmm15";
	_  -> sLit "very naughty x86_64 register"
      })
#else
     ppr_reg_no _ = panic "X86.Ppr.ppr_reg_no: no match"
#endif


pprSize :: Size -> Doc
pprSize x 
 = ptext (case x of
		II8   -> sLit "b"
		II16  -> sLit "w"
		II32  -> sLit "l"
		II64  -> sLit "q"
#if i386_TARGET_ARCH
		FF32  -> sLit "s"
		FF64  -> sLit "l"
		FF80  -> sLit "t"
#elif x86_64_TARGET_ARCH
		FF32  -> sLit "ss"	-- "scalar single-precision float" (SSE2)
		FF64  -> sLit "sd"	-- "scalar double-precision float" (SSE2)
                _     -> panic "X86.Ppr.pprSize: no match"
#else
		_     -> panic "X86.Ppr.pprSize: no match"
#endif
	        )

pprCond :: Cond -> Doc
pprCond c
 = ptext (case c of {
		GEU	-> sLit "ae";	LU    -> sLit "b";
		EQQ	-> sLit "e";	GTT   -> sLit "g";
		GE	-> sLit "ge";	GU    -> sLit "a";
		LTT	-> sLit "l";	LE    -> sLit "le";
		LEU	-> sLit "be";	NE    -> sLit "ne";
		NEG	-> sLit "s";	POS   -> sLit "ns";
	        CARRY   -> sLit "c";   OFLO  -> sLit "o";
		PARITY  -> sLit "p";   NOTPARITY -> sLit "np";
		ALWAYS	-> sLit "mp"})


pprImm :: Imm -> Doc
pprImm (ImmInt i)     = int i
pprImm (ImmInteger i) = integer i
pprImm (ImmCLbl l)    = pprCLabel_asm l
pprImm (ImmIndex l i) = pprCLabel_asm l <> char '+' <> int i
pprImm (ImmLit s)     = s

pprImm (ImmFloat _)  = ptext (sLit "naughty float immediate")
pprImm (ImmDouble _) = ptext (sLit "naughty double immediate")

pprImm (ImmConstantSum a b) = pprImm a <> char '+' <> pprImm b
pprImm (ImmConstantDiff a b) = pprImm a <> char '-'
                            <> lparen <> pprImm b <> rparen



pprAddr :: AddrMode -> Doc
pprAddr (ImmAddr imm off)
  = let	pp_imm = pprImm imm
    in
    if (off == 0) then
	pp_imm
    else if (off < 0) then
	pp_imm <> int off
    else
	pp_imm <> char '+' <> int off

pprAddr (AddrBaseIndex base index displacement)
  = let
	pp_disp  = ppr_disp displacement
	pp_off p = pp_disp <> char '(' <> p <> char ')'
	pp_reg r = pprReg archWordSize r
    in
    case (base, index) of
      (EABaseNone,  EAIndexNone) -> pp_disp
      (EABaseReg b, EAIndexNone) -> pp_off (pp_reg b)
      (EABaseRip,   EAIndexNone) -> pp_off (ptext (sLit "%rip"))
      (EABaseNone,  EAIndex r i) -> pp_off (comma <> pp_reg r <> comma <> int i)
      (EABaseReg b, EAIndex r i) -> pp_off (pp_reg b <> comma <> pp_reg r 
                                       <> comma <> int i)
      _				-> panic "X86.Ppr.pprAddr: no match"
	
  where
    ppr_disp (ImmInt 0) = empty
    ppr_disp imm        = pprImm imm


pprSectionHeader :: Section -> Doc
#if  i386_TARGET_ARCH

#    if darwin_TARGET_OS 
pprSectionHeader seg
 = case seg of
 	Text			-> ptext (sLit ".text\n\t.align 2")
	Data			-> ptext (sLit ".data\n\t.align 2")
	ReadOnlyData		-> ptext (sLit ".const\n.align 2")
	RelocatableReadOnlyData	-> ptext (sLit ".const_data\n.align 2")
	UninitialisedData	-> ptext (sLit ".data\n\t.align 2")
	ReadOnlyData16		-> ptext (sLit ".const\n.align 4")
	OtherSection _		-> panic "X86.Ppr.pprSectionHeader: unknown section"

#    else
pprSectionHeader seg
 = case seg of
 	Text			-> ptext (sLit ".text\n\t.align 4,0x90")
	Data			-> ptext (sLit ".data\n\t.align 4")
	ReadOnlyData		-> ptext (sLit ".section .rodata\n\t.align 4")
	RelocatableReadOnlyData	-> ptext (sLit ".section .data\n\t.align 4")
	UninitialisedData	-> ptext (sLit ".section .bss\n\t.align 4")
	ReadOnlyData16		-> ptext (sLit ".section .rodata\n\t.align 16")
	OtherSection _		-> panic "X86.Ppr.pprSectionHeader: unknown section"

#    endif

#elif x86_64_TARGET_ARCH
#    if  darwin_TARGET_OS 
pprSectionHeader seg
 = case seg of
	Text			-> ptext (sLit ".text\n.align 3")
	Data   			-> ptext (sLit ".data\n.align 3")
	ReadOnlyData		-> ptext (sLit ".const\n.align 3")
	RelocatableReadOnlyData	-> ptext (sLit ".const_data\n.align 3")
	UninitialisedData	-> ptext (sLit ".data\n\t.align 3")
	ReadOnlyData16		-> ptext (sLit ".const\n.align 4")
	OtherSection _		-> panic "PprMach.pprSectionHeader: unknown section"

#    else
pprSectionHeader seg
 = case seg of
	Text			-> ptext (sLit ".text\n\t.align 8")
	Data   			-> ptext (sLit ".data\n\t.align 8")
	ReadOnlyData		-> ptext (sLit ".section .rodata\n\t.align 8")
	RelocatableReadOnlyData	-> ptext (sLit ".section .data\n\t.align 8")
	UninitialisedData	-> ptext (sLit ".section .bss\n\t.align 8")
	ReadOnlyData16		-> ptext (sLit ".section .rodata.cst16\n\t.align 16")
	OtherSection _		-> panic "PprMach.pprSectionHeader: unknown section"

#    endif

#else
pprSectionHeader _		= panic "X86.Ppr.pprSectionHeader: not defined for this architecture"

#endif




pprDataItem :: CmmLit -> Doc
pprDataItem lit
  = vcat (ppr_item (cmmTypeSize $ cmmLitType lit) lit)
    where
	imm = litToImm lit

	-- These seem to be common:
	ppr_item II8   _ = [ptext (sLit "\t.byte\t") <> pprImm imm]
	ppr_item II32  _ = [ptext (sLit "\t.long\t") <> pprImm imm]

	ppr_item FF32  (CmmFloat r _)
           = let bs = floatToBytes (fromRational r)
             in  map (\b -> ptext (sLit "\t.byte\t") <> pprImm (ImmInt b)) bs

    	ppr_item FF64 (CmmFloat r _)
           = let bs = doubleToBytes (fromRational r)
             in  map (\b -> ptext (sLit "\t.byte\t") <> pprImm (ImmInt b)) bs

#if i386_TARGET_ARCH || x86_64_TARGET_ARCH
	ppr_item II16  _ = [ptext (sLit "\t.word\t") <> pprImm imm]
#endif
#if i386_TARGET_ARCH && darwin_TARGET_OS
        ppr_item II64 (CmmInt x _)  =
                [ptext (sLit "\t.long\t")
                    <> int (fromIntegral (fromIntegral x :: Word32)),
                 ptext (sLit "\t.long\t")
                    <> int (fromIntegral
                        (fromIntegral (x `shiftR` 32) :: Word32))]
#endif
#if i386_TARGET_ARCH || (darwin_TARGET_OS && x86_64_TARGET_ARCH)
	ppr_item II64  _ = [ptext (sLit "\t.quad\t") <> pprImm imm]
#endif
#if x86_64_TARGET_ARCH && !darwin_TARGET_OS
	-- x86_64: binutils can't handle the R_X86_64_PC64 relocation
	-- type, which means we can't do pc-relative 64-bit addresses.
	-- Fortunately we're assuming the small memory model, in which
	-- all such offsets will fit into 32 bits, so we have to stick
	-- to 32-bit offset fields and modify the RTS appropriately
        --
        -- See Note [x86-64-relative] in includes/rts/storage/InfoTables.h
	-- 
	ppr_item II64  x 
	   | isRelativeReloc x =
		[ptext (sLit "\t.long\t") <> pprImm imm,
		 ptext (sLit "\t.long\t0")]
	   | otherwise =
		[ptext (sLit "\t.quad\t") <> pprImm imm]
	   where
		isRelativeReloc (CmmLabelDiffOff _ _ _) = True
		isRelativeReloc _ = False
#endif

	ppr_item _ _
		= panic "X86.Ppr.ppr_item: no match"



pprInstr :: Instr -> Doc

pprInstr (COMMENT _) = empty -- nuke 'em
{-
pprInstr (COMMENT s)
   =  IF_ARCH_alpha( ((<>) (ptext (sLit "\t# ")) (ftext s))
     ,IF_ARCH_sparc( ((<>) (ptext (sLit "# "))   (ftext s))
     ,IF_ARCH_i386( ((<>) (ptext (sLit "# "))   (ftext s))
     ,IF_ARCH_x86_64( ((<>) (ptext (sLit "# "))   (ftext s))
     ,IF_ARCH_powerpc( IF_OS_linux(
        ((<>) (ptext (sLit "# ")) (ftext s)),
        ((<>) (ptext (sLit "; ")) (ftext s)))
     ,)))))
-}
pprInstr (DELTA d)
   = pprInstr (COMMENT (mkFastString ("\tdelta = " ++ show d)))

pprInstr (NEWBLOCK _)
   = panic "PprMach.pprInstr: NEWBLOCK"

pprInstr (LDATA _ _)
   = panic "PprMach.pprInstr: LDATA"

{-
pprInstr (SPILL reg slot)
   = hcat [
   	ptext (sLit "\tSPILL"),
	char ' ',
	pprUserReg reg,
	comma,
	ptext (sLit "SLOT") <> parens (int slot)]

pprInstr (RELOAD slot reg)
   = hcat [
   	ptext (sLit "\tRELOAD"),
	char ' ',
	ptext (sLit "SLOT") <> parens (int slot),
	comma,
	pprUserReg reg]
-}

pprInstr (MOV size src dst)
  = pprSizeOpOp (sLit "mov") size src dst

pprInstr (MOVZxL II32 src dst) = pprSizeOpOp (sLit "mov") II32 src dst
	-- 32-to-64 bit zero extension on x86_64 is accomplished by a simple
	-- movl.  But we represent it as a MOVZxL instruction, because
	-- the reg alloc would tend to throw away a plain reg-to-reg
	-- move, and we still want it to do that.

pprInstr (MOVZxL sizes src dst) = pprSizeOpOpCoerce (sLit "movz") sizes II32 src dst
	-- zero-extension only needs to extend to 32 bits: on x86_64, 
	-- the remaining zero-extension to 64 bits is automatic, and the 32-bit
	-- instruction is shorter.

pprInstr (MOVSxL sizes src dst) = pprSizeOpOpCoerce (sLit "movs") sizes archWordSize src dst

-- here we do some patching, since the physical registers are only set late
-- in the code generation.
pprInstr (LEA size (OpAddr (AddrBaseIndex (EABaseReg reg1) (EAIndex reg2 1) (ImmInt 0))) dst@(OpReg reg3))
  | reg1 == reg3
  = pprSizeOpOp (sLit "add") size (OpReg reg2) dst

pprInstr (LEA size (OpAddr (AddrBaseIndex (EABaseReg reg1) (EAIndex reg2 1) (ImmInt 0))) dst@(OpReg reg3))
  | reg2 == reg3
  = pprSizeOpOp (sLit "add") size (OpReg reg1) dst

pprInstr (LEA size (OpAddr (AddrBaseIndex (EABaseReg reg1) EAIndexNone displ)) dst@(OpReg reg3))
  | reg1 == reg3
  = pprInstr (ADD size (OpImm displ) dst)

pprInstr (LEA size src dst) = pprSizeOpOp (sLit "lea") size src dst

pprInstr (ADD size (OpImm (ImmInt (-1))) dst)
  = pprSizeOp (sLit "dec") size dst
pprInstr (ADD size (OpImm (ImmInt 1)) dst)
  = pprSizeOp (sLit "inc") size dst
pprInstr (ADD size src dst)
  = pprSizeOpOp (sLit "add") size src dst
pprInstr (ADC size src dst)
  = pprSizeOpOp (sLit "adc") size src dst
pprInstr (SUB size src dst) = pprSizeOpOp (sLit "sub") size src dst
pprInstr (IMUL size op1 op2) = pprSizeOpOp (sLit "imul") size op1 op2

{- A hack.  The Intel documentation says that "The two and three
   operand forms [of IMUL] may also be used with unsigned operands
   because the lower half of the product is the same regardless if
   (sic) the operands are signed or unsigned.  The CF and OF flags,
   however, cannot be used to determine if the upper half of the
   result is non-zero."  So there.  
-} 
pprInstr (AND size src dst) = pprSizeOpOp (sLit "and") size src dst
pprInstr (OR  size src dst) = pprSizeOpOp (sLit "or")  size src dst

pprInstr (XOR FF32 src dst) = pprOpOp (sLit "xorps") FF32 src dst
pprInstr (XOR FF64 src dst) = pprOpOp (sLit "xorpd") FF64 src dst
pprInstr (XOR size src dst) = pprSizeOpOp (sLit "xor")  size src dst

pprInstr (NOT size op) = pprSizeOp (sLit "not") size op
pprInstr (NEGI size op) = pprSizeOp (sLit "neg") size op

pprInstr (SHL size src dst) = pprShift (sLit "shl") size src dst
pprInstr (SAR size src dst) = pprShift (sLit "sar") size src dst
pprInstr (SHR size src dst) = pprShift (sLit "shr") size src dst

pprInstr (BT  size imm src) = pprSizeImmOp (sLit "bt") size imm src

pprInstr (CMP size src dst) 
  | is_float size =  pprSizeOpOp (sLit "ucomi") size src dst -- SSE2
  | otherwise     =  pprSizeOpOp (sLit "cmp")   size src dst
  where
	-- This predicate is needed here and nowhere else
    is_float FF32	= True	
    is_float FF64	= True
    is_float FF80	= True
    is_float _		= False

pprInstr (TEST size src dst) = pprSizeOpOp (sLit "test")  size src dst
pprInstr (PUSH size op) = pprSizeOp (sLit "push") size op
pprInstr (POP size op) = pprSizeOp (sLit "pop") size op

-- both unused (SDM):
-- pprInstr PUSHA = ptext (sLit "\tpushal")
-- pprInstr POPA = ptext (sLit "\tpopal")

pprInstr NOP = ptext (sLit "\tnop")
pprInstr (CLTD II32) = ptext (sLit "\tcltd")
pprInstr (CLTD II64) = ptext (sLit "\tcqto")

pprInstr (SETCC cond op) = pprCondInstr (sLit "set") cond (pprOperand II8 op)

pprInstr (JXX cond (BlockId id)) 
  = pprCondInstr (sLit "j") cond (pprCLabel_asm lab)
  where lab = mkAsmTempLabel id

pprInstr (JXX_GBL cond imm) = pprCondInstr (sLit "j") cond (pprImm imm)

pprInstr (JMP (OpImm imm)) = (<>) (ptext (sLit "\tjmp ")) (pprImm imm)
pprInstr (JMP op)          = (<>) (ptext (sLit "\tjmp *")) (pprOperand archWordSize op)
pprInstr (JMP_TBL op _)  = pprInstr (JMP op)
pprInstr (CALL (Left imm) _)    = (<>) (ptext (sLit "\tcall ")) (pprImm imm)
pprInstr (CALL (Right reg) _)   = (<>) (ptext (sLit "\tcall *")) (pprReg archWordSize reg)

pprInstr (IDIV sz op)	= pprSizeOp (sLit "idiv") sz op
pprInstr (DIV sz op)    = pprSizeOp (sLit "div")  sz op
pprInstr (IMUL2 sz op)  = pprSizeOp (sLit "imul") sz op

-- x86_64 only
pprInstr (MUL size op1 op2) = pprSizeOpOp (sLit "mul") size op1 op2

pprInstr (FDIV size op1 op2) = pprSizeOpOp (sLit "div") size op1 op2

pprInstr (CVTSS2SD from to)   = pprRegReg (sLit "cvtss2sd") from to
pprInstr (CVTSD2SS from to)   = pprRegReg (sLit "cvtsd2ss") from to
pprInstr (CVTTSS2SIQ from to) = pprOpReg  (sLit "cvttss2siq") from to
pprInstr (CVTTSD2SIQ from to) = pprOpReg  (sLit "cvttsd2siq") from to
pprInstr (CVTSI2SS from to)   = pprOpReg  (sLit "cvtsi2ssq") from to
pprInstr (CVTSI2SD from to)   = pprOpReg  (sLit "cvtsi2sdq") from to

    -- FETCHGOT for PIC on ELF platforms
pprInstr (FETCHGOT reg)
   = vcat [ ptext (sLit "\tcall 1f"),
            hcat [ ptext (sLit "1:\tpopl\t"), pprReg II32 reg ],
            hcat [ ptext (sLit "\taddl\t$_GLOBAL_OFFSET_TABLE_+(.-1b), "),
                   pprReg II32 reg ]
          ]

    -- FETCHPC for PIC on Darwin/x86
    -- get the instruction pointer into a register
    -- (Terminology note: the IP is called Program Counter on PPC,
    --  and it's a good thing to use the same name on both platforms)
pprInstr (FETCHPC reg)
   = vcat [ ptext (sLit "\tcall 1f"),
            hcat [ ptext (sLit "1:\tpopl\t"), pprReg II32 reg ]
          ]


-- -----------------------------------------------------------------------------
-- i386 floating-point

-- Simulating a flat register set on the x86 FP stack is tricky.
-- you have to free %st(7) before pushing anything on the FP reg stack
-- so as to preclude the possibility of a FP stack overflow exception.
pprInstr g@(GMOV src dst)
   | src == dst
   = empty
   | otherwise 
   = pprG g (hcat [gtab, gpush src 0, gsemi, gpop dst 1])

-- GLD sz addr dst ==> FFREE %st(7) ; FLDsz addr ; FSTP (dst+1)
pprInstr g@(GLD sz addr dst)
 = pprG g (hcat [gtab, text "ffree %st(7) ; fld", pprSize sz, gsp, 
                 pprAddr addr, gsemi, gpop dst 1])

-- GST sz src addr ==> FFREE %st(7) ; FLD dst ; FSTPsz addr
pprInstr g@(GST sz src addr)
 = pprG g (hcat [gtab, gpush src 0, gsemi, 
                 text "fstp", pprSize sz, gsp, pprAddr addr])

pprInstr g@(GLDZ dst)
 = pprG g (hcat [gtab, text "ffree %st(7) ; fldz ; ", gpop dst 1])
pprInstr g@(GLD1 dst)
 = pprG g (hcat [gtab, text "ffree %st(7) ; fld1 ; ", gpop dst 1])

pprInstr (GFTOI src dst) 
   = pprInstr (GDTOI src dst)

pprInstr g@(GDTOI src dst) 
   = pprG g (vcat [
         hcat [gtab, text "subl $8, %esp ; fnstcw 4(%esp)"],
         hcat [gtab, gpush src 0],
         hcat [gtab, text "movzwl 4(%esp), ", reg,
                     text " ; orl $0xC00, ", reg],
         hcat [gtab, text "movl ", reg, text ", 0(%esp) ; fldcw 0(%esp)"],
         hcat [gtab, text "fistpl 0(%esp)"],
         hcat [gtab, text "fldcw 4(%esp) ; movl 0(%esp), ", reg],
         hcat [gtab, text "addl $8, %esp"]
     ])
   where
     reg = pprReg II32 dst

pprInstr (GITOF src dst) 
   = pprInstr (GITOD src dst)

pprInstr g@(GITOD src dst) 
   = pprG g (hcat [gtab, text "pushl ", pprReg II32 src, 
                   text " ; ffree %st(7); fildl (%esp) ; ",
                   gpop dst 1, text " ; addl $4,%esp"])

{- Gruesome swamp follows.  If you're unfortunate enough to have ventured
   this far into the jungle AND you give a Rat's Ass (tm) what's going
   on, here's the deal.  Generate code to do a floating point comparison
   of src1 and src2, of kind cond, and set the Zero flag if true.

   The complications are to do with handling NaNs correctly.  We want the
   property that if either argument is NaN, then the result of the
   comparison is False ... except if we're comparing for inequality,
   in which case the answer is True.

   Here's how the general (non-inequality) case works.  As an
   example, consider generating the an equality test:

     pushl %eax		-- we need to mess with this
     <get src1 to top of FPU stack>
     fcomp <src2 location in FPU stack> and pop pushed src1
		-- Result of comparison is in FPU Status Register bits
		-- C3 C2 and C0
     fstsw %ax	-- Move FPU Status Reg to %ax
     sahf	-- move C3 C2 C0 from %ax to integer flag reg
     -- now the serious magic begins
     setpo %ah	   -- %ah = if comparable(neither arg was NaN) then 1 else 0
     sete  %al     -- %al = if arg1 == arg2 then 1 else 0
     andb %ah,%al  -- %al &= %ah
                   -- so %al == 1 iff (comparable && same); else it holds 0
     decb %al	   -- %al == 0, ZeroFlag=1  iff (comparable && same); 
                      else %al == 0xFF, ZeroFlag=0
     -- the zero flag is now set as we desire.
     popl %eax

   The special case of inequality differs thusly:

     setpe %ah     -- %ah = if incomparable(either arg was NaN) then 1 else 0
     setne %al     -- %al = if arg1 /= arg2 then 1 else 0
     orb %ah,%al   -- %al = if (incomparable || different) then 1 else 0
     decb %al      -- if (incomparable || different) then (%al == 0, ZF=1)
                                                     else (%al == 0xFF, ZF=0)
-}
pprInstr g@(GCMP cond src1 src2) 
   | case cond of { NE -> True; _ -> False }
   = pprG g (vcat [
        hcat [gtab, text "pushl %eax ; ",gpush src1 0],
        hcat [gtab, text "fcomp ", greg src2 1, 
                    text "; fstsw %ax ; sahf ;  setpe %ah"],
        hcat [gtab, text "setne %al ;  ",
              text "orb %ah,%al ;  decb %al ;  popl %eax"]
    ])
   | otherwise
   = pprG g (vcat [
        hcat [gtab, text "pushl %eax ; ",gpush src1 0],
        hcat [gtab, text "fcomp ", greg src2 1, 
                    text "; fstsw %ax ; sahf ;  setpo %ah"],
        hcat [gtab, text "set", pprCond (fix_FP_cond cond), text " %al ;  ",
              text "andb %ah,%al ;  decb %al ;  popl %eax"]
    ])
    where
        {- On the 486, the flags set by FP compare are the unsigned ones!
           (This looks like a HACK to me.  WDP 96/03)
        -}
        fix_FP_cond :: Cond -> Cond
        fix_FP_cond GE   = GEU
        fix_FP_cond GTT  = GU
        fix_FP_cond LTT  = LU
        fix_FP_cond LE   = LEU
        fix_FP_cond EQQ  = EQQ
        fix_FP_cond NE   = NE
	fix_FP_cond _	 = panic "X86.Ppr.fix_FP_cond: no match"
        -- there should be no others


pprInstr g@(GABS _ src dst)
   = pprG g (hcat [gtab, gpush src 0, text " ; fabs ; ", gpop dst 1])

pprInstr g@(GNEG _ src dst)
   = pprG g (hcat [gtab, gpush src 0, text " ; fchs ; ", gpop dst 1])

pprInstr g@(GSQRT sz src dst)
   = pprG g (hcat [gtab, gpush src 0, text " ; fsqrt"] $$ 
             hcat [gtab, gcoerceto sz, gpop dst 1])

pprInstr g@(GSIN sz l1 l2 src dst)
   = pprG g (pprTrigOp "fsin" False l1 l2 src dst sz)

pprInstr g@(GCOS sz l1 l2 src dst)
   = pprG g (pprTrigOp "fcos" False l1 l2 src dst sz)

pprInstr g@(GTAN sz l1 l2 src dst)
   = pprG g (pprTrigOp "fptan" True l1 l2 src dst sz)

-- In the translations for GADD, GMUL, GSUB and GDIV,
-- the first two cases are mere optimisations.  The otherwise clause
-- generates correct code under all circumstances.

pprInstr g@(GADD _ src1 src2 dst)
   | src1 == dst
   = pprG g (text "\t#GADD-xxxcase1" $$ 
             hcat [gtab, gpush src2 0,
                   text " ; faddp %st(0),", greg src1 1])
   | src2 == dst
   = pprG g (text "\t#GADD-xxxcase2" $$ 
             hcat [gtab, gpush src1 0,
                   text " ; faddp %st(0),", greg src2 1])
   | otherwise
   = pprG g (hcat [gtab, gpush src1 0, 
                   text " ; fadd ", greg src2 1, text ",%st(0)",
                   gsemi, gpop dst 1])


pprInstr g@(GMUL _ src1 src2 dst)
   | src1 == dst
   = pprG g (text "\t#GMUL-xxxcase1" $$ 
             hcat [gtab, gpush src2 0,
                   text " ; fmulp %st(0),", greg src1 1])
   | src2 == dst
   = pprG g (text "\t#GMUL-xxxcase2" $$ 
             hcat [gtab, gpush src1 0,
                   text " ; fmulp %st(0),", greg src2 1])
   | otherwise
   = pprG g (hcat [gtab, gpush src1 0, 
                   text " ; fmul ", greg src2 1, text ",%st(0)",
                   gsemi, gpop dst 1])


pprInstr g@(GSUB _ src1 src2 dst)
   | src1 == dst
   = pprG g (text "\t#GSUB-xxxcase1" $$ 
             hcat [gtab, gpush src2 0,
                   text " ; fsubrp %st(0),", greg src1 1])
   | src2 == dst
   = pprG g (text "\t#GSUB-xxxcase2" $$ 
             hcat [gtab, gpush src1 0,
                   text " ; fsubp %st(0),", greg src2 1])
   | otherwise
   = pprG g (hcat [gtab, gpush src1 0, 
                   text " ; fsub ", greg src2 1, text ",%st(0)",
                   gsemi, gpop dst 1])


pprInstr g@(GDIV _ src1 src2 dst)
   | src1 == dst
   = pprG g (text "\t#GDIV-xxxcase1" $$ 
             hcat [gtab, gpush src2 0,
                   text " ; fdivrp %st(0),", greg src1 1])
   | src2 == dst
   = pprG g (text "\t#GDIV-xxxcase2" $$ 
             hcat [gtab, gpush src1 0,
                   text " ; fdivp %st(0),", greg src2 1])
   | otherwise
   = pprG g (hcat [gtab, gpush src1 0, 
                   text " ; fdiv ", greg src2 1, text ",%st(0)",
                   gsemi, gpop dst 1])


pprInstr GFREE 
   = vcat [ ptext (sLit "\tffree %st(0) ;ffree %st(1) ;ffree %st(2) ;ffree %st(3)"),
            ptext (sLit "\tffree %st(4) ;ffree %st(5) ;ffree %st(6) ;ffree %st(7)") 
          ]

pprInstr _
	= panic "X86.Ppr.pprInstr: no match"


pprTrigOp :: String -> Bool -> CLabel -> CLabel -> Reg -> Reg -> Size -> Doc
pprTrigOp op -- fsin, fcos or fptan
          isTan -- we need a couple of extra steps if we're doing tan
          l1 l2 -- internal labels for us to use
          src dst sz
    = -- We'll be needing %eax later on
      hcat [gtab, text "pushl %eax;"] $$
      -- tan is going to use an extra space on the FP stack
      (if isTan then hcat [gtab, text "ffree %st(6)"] else empty) $$
      -- First put the value in %st(0) and try to apply the op to it
      hcat [gpush src 0, text ("; " ++ op)] $$
      -- Now look to see if C2 was set (overflow, |value| >= 2^63)
      hcat [gtab, text "fnstsw %ax"] $$
      hcat [gtab, text "test   $0x400,%eax"] $$
      -- If we were in bounds then jump to the end
      hcat [gtab, text "je     " <> pprCLabel_asm l1] $$
      -- Otherwise we need to shrink the value. Start by
      -- loading pi, doubleing it (by adding it to itself),
      -- and then swapping pi with the value, so the value we
      -- want to apply op to is in %st(0) again
      hcat [gtab, text "ffree %st(7); fldpi"] $$
      hcat [gtab, text "fadd   %st(0),%st"] $$
      hcat [gtab, text "fxch   %st(1)"] $$
      -- Now we have a loop in which we make the value smaller,
      -- see if it's small enough, and loop if not
      (pprCLabel_asm l2 <> char ':') $$
      hcat [gtab, text "fprem1"] $$
      -- My Debian libc uses fstsw here for the tan code, but I can't
      -- see any reason why it should need to be different for tan.
      hcat [gtab, text "fnstsw %ax"] $$
      hcat [gtab, text "test   $0x400,%eax"] $$
      hcat [gtab, text "jne    " <> pprCLabel_asm l2] $$
      hcat [gtab, text "fstp   %st(1)"] $$
      hcat [gtab, text op] $$
      (pprCLabel_asm l1 <> char ':') $$
      -- Pop the 1.0 tan gave us
      (if isTan then hcat [gtab, text "fstp %st(0)"] else empty) $$
      -- Restore %eax
      hcat [gtab, text "popl %eax;"] $$
      -- And finally make the result the right size
      hcat [gtab, gcoerceto sz, gpop dst 1]

--------------------------

-- coerce %st(0) to the specified size
gcoerceto :: Size -> Doc
gcoerceto FF64 = empty
gcoerceto FF32 = empty --text "subl $4,%esp ; fstps (%esp) ; flds (%esp) ; addl $4,%esp ; "
gcoerceto _    = panic "X86.Ppr.gcoerceto: no match"

gpush :: Reg -> RegNo -> Doc
gpush reg offset
   = hcat [text "ffree %st(7) ; fld ", greg reg offset]


gpop :: Reg -> RegNo -> Doc
gpop reg offset
   = hcat [text "fstp ", greg reg offset]

greg :: Reg -> RegNo -> Doc
greg reg offset = text "%st(" <> int (gregno reg - 8+offset) <> char ')'

gsemi :: Doc
gsemi = text " ; "

gtab :: Doc
gtab  = char '\t'

gsp :: Doc
gsp   = char ' '

gregno :: Reg -> RegNo
gregno (RegReal (RealRegSingle i)) = i
gregno _           = --pprPanic "gregno" (ppr other)
                     999   -- bogus; only needed for debug printing

pprG :: Instr -> Doc -> Doc
pprG fake actual
   = (char '#' <> pprGInstr fake) $$ actual


pprGInstr :: Instr -> Doc
pprGInstr (GMOV src dst)   = pprSizeRegReg (sLit "gmov") FF64 src dst
pprGInstr (GLD sz src dst) = pprSizeAddrReg (sLit "gld") sz src dst
pprGInstr (GST sz src dst) = pprSizeRegAddr (sLit "gst") sz src dst

pprGInstr (GLDZ dst) = pprSizeReg (sLit "gldz") FF64 dst
pprGInstr (GLD1 dst) = pprSizeReg (sLit "gld1") FF64 dst

pprGInstr (GFTOI src dst) = pprSizeSizeRegReg (sLit "gftoi") FF32 II32  src dst
pprGInstr (GDTOI src dst) = pprSizeSizeRegReg (sLit "gdtoi") FF64 II32 src dst

pprGInstr (GITOF src dst) = pprSizeSizeRegReg (sLit "gitof") II32 FF32  src dst
pprGInstr (GITOD src dst) = pprSizeSizeRegReg (sLit "gitod") II32 FF64 src dst

pprGInstr (GCMP co src dst) = pprCondRegReg (sLit "gcmp_") FF64 co src dst
pprGInstr (GABS sz src dst) = pprSizeRegReg (sLit "gabs") sz src dst
pprGInstr (GNEG sz src dst) = pprSizeRegReg (sLit "gneg") sz src dst
pprGInstr (GSQRT sz src dst) = pprSizeRegReg (sLit "gsqrt") sz src dst
pprGInstr (GSIN sz _ _ src dst) = pprSizeRegReg (sLit "gsin") sz src dst
pprGInstr (GCOS sz _ _ src dst) = pprSizeRegReg (sLit "gcos") sz src dst
pprGInstr (GTAN sz _ _ src dst) = pprSizeRegReg (sLit "gtan") sz src dst

pprGInstr (GADD sz src1 src2 dst) = pprSizeRegRegReg (sLit "gadd") sz src1 src2 dst
pprGInstr (GSUB sz src1 src2 dst) = pprSizeRegRegReg (sLit "gsub") sz src1 src2 dst
pprGInstr (GMUL sz src1 src2 dst) = pprSizeRegRegReg (sLit "gmul") sz src1 src2 dst
pprGInstr (GDIV sz src1 src2 dst) = pprSizeRegRegReg (sLit "gdiv") sz src1 src2 dst

pprGInstr _ = panic "X86.Ppr.pprGInstr: no match"

pprDollImm :: Imm -> Doc
pprDollImm i =  ptext (sLit "$") <> pprImm i


pprOperand :: Size -> Operand -> Doc
pprOperand s (OpReg r)   = pprReg s r
pprOperand _ (OpImm i)   = pprDollImm i
pprOperand _ (OpAddr ea) = pprAddr ea


pprMnemonic_  :: LitString -> Doc
pprMnemonic_ name = 
   char '\t' <> ptext name <> space


pprMnemonic  :: LitString -> Size -> Doc
pprMnemonic name size = 
   char '\t' <> ptext name <> pprSize size <> space


pprSizeImmOp :: LitString -> Size -> Imm -> Operand -> Doc
pprSizeImmOp name size imm op1
  = hcat [
	pprMnemonic name size,
	char '$',
	pprImm imm,
	comma,
	pprOperand size op1
    ]

	
pprSizeOp :: LitString -> Size -> Operand -> Doc
pprSizeOp name size op1
  = hcat [
	pprMnemonic name size,
	pprOperand size op1
    ]


pprSizeOpOp :: LitString -> Size -> Operand -> Operand -> Doc
pprSizeOpOp name size op1 op2
  = hcat [
	pprMnemonic name size,
	pprOperand size op1,
	comma,
	pprOperand size op2
    ]


pprOpOp :: LitString -> Size -> Operand -> Operand -> Doc
pprOpOp name size op1 op2
  = hcat [
	pprMnemonic_ name,
	pprOperand size op1,
	comma,
	pprOperand size op2
    ]


pprSizeReg :: LitString -> Size -> Reg -> Doc
pprSizeReg name size reg1
  = hcat [
	pprMnemonic name size,
	pprReg size reg1
    ]


pprSizeRegReg :: LitString -> Size -> Reg -> Reg -> Doc
pprSizeRegReg name size reg1 reg2
  = hcat [
	pprMnemonic name size,
	pprReg size reg1,
        comma,
        pprReg size reg2
    ]


pprRegReg :: LitString -> Reg -> Reg -> Doc
pprRegReg name reg1 reg2
  = hcat [
	pprMnemonic_ name,
	pprReg archWordSize reg1,
        comma,
        pprReg archWordSize reg2
    ]


pprOpReg :: LitString -> Operand -> Reg -> Doc
pprOpReg name op1 reg2
  = hcat [
	pprMnemonic_ name,
	pprOperand archWordSize op1,
        comma,
        pprReg archWordSize reg2
    ]


pprCondRegReg :: LitString -> Size -> Cond -> Reg -> Reg -> Doc
pprCondRegReg name size cond reg1 reg2
  = hcat [
    	char '\t',
	ptext name,
    	pprCond cond,
	space,
	pprReg size reg1,
        comma,
        pprReg size reg2
    ]

pprSizeSizeRegReg :: LitString -> Size -> Size -> Reg -> Reg -> Doc
pprSizeSizeRegReg name size1 size2 reg1 reg2
  = hcat [
    	char '\t',
	ptext name,
    	pprSize size1,
        pprSize size2,
	space,
	pprReg size1 reg1,

        comma,
        pprReg size2 reg2
    ]


pprSizeRegRegReg :: LitString -> Size -> Reg -> Reg -> Reg -> Doc
pprSizeRegRegReg name size reg1 reg2 reg3
  = hcat [
	pprMnemonic name size,
	pprReg size reg1,
        comma,
        pprReg size reg2,
        comma,
        pprReg size reg3
    ]


pprSizeAddrReg :: LitString -> Size -> AddrMode -> Reg -> Doc
pprSizeAddrReg name size op dst
  = hcat [
	pprMnemonic name size,
	pprAddr op,
	comma,
	pprReg size dst
    ]


pprSizeRegAddr :: LitString -> Size -> Reg -> AddrMode -> Doc
pprSizeRegAddr name size src op
  = hcat [
	pprMnemonic name size,
	pprReg size src,
	comma,
	pprAddr op
    ]


pprShift :: LitString -> Size -> Operand -> Operand -> Doc
pprShift name size src dest
  = hcat [
	pprMnemonic name size,
	pprOperand II8 src,  -- src is 8-bit sized
	comma,
	pprOperand size dest
    ]


pprSizeOpOpCoerce :: LitString -> Size -> Size -> Operand -> Operand -> Doc
pprSizeOpOpCoerce name size1 size2 op1 op2
  = hcat [ char '\t', ptext name, pprSize size1, pprSize size2, space,
	pprOperand size1 op1,
	comma,
	pprOperand size2 op2
    ]


pprCondInstr :: LitString -> Cond -> Doc -> Doc
pprCondInstr name cond arg
  = hcat [ char '\t', ptext name, pprCond cond, space, arg]

