+{-# OPTIONS -w #-}
+-- The above warning supression flag is a temporary kludge.
+-- While working on this module you are encouraged to remove it and fix
+-- any warnings in the module. See
+-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
+-- for details
+
-----------------------------------------------------------------------------
--
-- (c) The University of Glasgow 2004-2006
--
-----------------------------------------------------------------------------
-
module CgCallConv (
-- Argument descriptors
mkArgDescr, argDescrType,
-- Liveness
- isBigLiveness, buildContLiveness, mkRegLiveness,
+ isBigLiveness, mkRegLiveness,
smallLiveness, mkLivenessCLit,
-- Register assignment
constructSlowCall, slowArgs, slowCallPattern,
-- Returns
- CtrlReturnConvention(..),
- ctrlReturnConvAlg,
dataReturnConvPrim,
getSequelAmode
) where
-#include "HsVersions.h"
-
import CgUtils
import CgMonad
import SMRep
-import MachOp
import Cmm
import CLabel
import Maybes
import Id
import Name
-import TyCon
import Bitmap
import Util
import StaticFlags
import FastString
import Outputable
+import Unique
import Data.Bits
#include "../includes/StgFun.h"
-------------------------
-argDescrType :: ArgDescr -> Int
+argDescrType :: ArgDescr -> StgHalfWord
-- The "argument type" RTS field type
argDescrType (ArgSpec n) = n
argDescrType (ArgGen liveness)
argBits (PtrArg : args) = False : argBits args
argBits (arg : args) = take (cgRepSizeW arg) (repeat True) ++ argBits args
-stdPattern :: [CgRep] -> Maybe Int
+stdPattern :: [CgRep] -> Maybe StgHalfWord
stdPattern [] = Just ARG_NONE -- just void args, probably
stdPattern [PtrArg] = Just ARG_P
--
-------------------------------------------------------------------------
+-- TODO: This along with 'mkArgDescr' should be unified
+-- with 'CmmInfo.mkLiveness'. However that would require
+-- potentially invasive changes to the 'ClosureInfo' type.
+-- For now, 'CmmInfo.mkLiveness' handles only continuations and
+-- this one handles liveness everything else. Another distinction
+-- between these two is that 'CmmInfo.mkLiveness' information
+-- about the stack layout, and this one is information about
+-- the heap layout of PAPs.
mkLiveness :: Name -> Int -> Bitmap -> FCode Liveness
mkLiveness name size bits
| size > mAX_SMALL_BITMAP_SIZE -- Bitmap does not fit in one word
- = do { let lbl = mkBitmapLabel name
- ; emitRODataLits lbl ( mkWordCLit (fromIntegral size)
+ = do { let lbl = mkBitmapLabel (getUnique name)
+ ; emitRODataLits "mkLiveness" lbl ( mkWordCLit (fromIntegral size)
: map mkWordCLit bits)
; return (BigLiveness lbl) }
all_non_ptrs = 0xff
reg_bits [] = 0
- reg_bits ((id, VanillaReg i) : regs) | isFollowableArg (idCgRep id)
+ reg_bits ((id, VanillaReg i _) : regs) | isFollowableArg (idCgRep id)
= (1 `shiftL` (i - 1)) .|. reg_bits regs
reg_bits (_ : regs)
= reg_bits regs
-- don't forget the zero case
constructSlowCall []
- = (mkRtsApFastLabel SLIT("stg_ap_0"), [], [])
+ = (mkRtsApFastLabel (sLit "stg_ap_0"), [], [])
constructSlowCall amodes
= (stg_ap_pat, these, rest)
stg_ap_pat = mkRtsApFastLabel arg_pat
(arg_pat, these, rest) = matchSlowPattern amodes
-enterRtsRetLabel arg_pat
- | tablesNextToCode = mkRtsRetInfoLabel arg_pat
- | otherwise = mkRtsRetLabel arg_pat
-
-- | 'slowArgs' takes a list of function arguments and prepares them for
-- pushing on the stack for "extra" arguments to a function which requires
-- fewer arguments than we currently have.
(these, rest) = splitAt n amodes
-- These cases were found to cover about 99% of all slow calls:
-slowCallPattern (PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: _) = (SLIT("stg_ap_pppppp"), 6)
-slowCallPattern (PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: _) = (SLIT("stg_ap_ppppp"), 5)
-slowCallPattern (PtrArg: PtrArg: PtrArg: PtrArg: _) = (SLIT("stg_ap_pppp"), 4)
-slowCallPattern (PtrArg: PtrArg: PtrArg: VoidArg: _) = (SLIT("stg_ap_pppv"), 4)
-slowCallPattern (PtrArg: PtrArg: PtrArg: _) = (SLIT("stg_ap_ppp"), 3)
-slowCallPattern (PtrArg: PtrArg: VoidArg: _) = (SLIT("stg_ap_ppv"), 3)
-slowCallPattern (PtrArg: PtrArg: _) = (SLIT("stg_ap_pp"), 2)
-slowCallPattern (PtrArg: VoidArg: _) = (SLIT("stg_ap_pv"), 2)
-slowCallPattern (PtrArg: _) = (SLIT("stg_ap_p"), 1)
-slowCallPattern (VoidArg: _) = (SLIT("stg_ap_v"), 1)
-slowCallPattern (NonPtrArg: _) = (SLIT("stg_ap_n"), 1)
-slowCallPattern (FloatArg: _) = (SLIT("stg_ap_f"), 1)
-slowCallPattern (DoubleArg: _) = (SLIT("stg_ap_d"), 1)
-slowCallPattern (LongArg: _) = (SLIT("stg_ap_l"), 1)
+slowCallPattern (PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: _) = (sLit "stg_ap_pppppp", 6)
+slowCallPattern (PtrArg: PtrArg: PtrArg: PtrArg: PtrArg: _) = (sLit "stg_ap_ppppp", 5)
+slowCallPattern (PtrArg: PtrArg: PtrArg: PtrArg: _) = (sLit "stg_ap_pppp", 4)
+slowCallPattern (PtrArg: PtrArg: PtrArg: VoidArg: _) = (sLit "stg_ap_pppv", 4)
+slowCallPattern (PtrArg: PtrArg: PtrArg: _) = (sLit "stg_ap_ppp", 3)
+slowCallPattern (PtrArg: PtrArg: VoidArg: _) = (sLit "stg_ap_ppv", 3)
+slowCallPattern (PtrArg: PtrArg: _) = (sLit "stg_ap_pp", 2)
+slowCallPattern (PtrArg: VoidArg: _) = (sLit "stg_ap_pv", 2)
+slowCallPattern (PtrArg: _) = (sLit "stg_ap_p", 1)
+slowCallPattern (VoidArg: _) = (sLit "stg_ap_v", 1)
+slowCallPattern (NonPtrArg: _) = (sLit "stg_ap_n", 1)
+slowCallPattern (FloatArg: _) = (sLit "stg_ap_f", 1)
+slowCallPattern (DoubleArg: _) = (sLit "stg_ap_d", 1)
+slowCallPattern (LongArg: _) = (sLit "stg_ap_l", 1)
slowCallPattern _ = panic "CgStackery.slowCallPattern"
-------------------------------------------------------------------------
--
-------------------------------------------------------------------------
--- A @CtrlReturnConvention@ says how {\em control} is returned.
-
-data CtrlReturnConvention
- = VectoredReturn Int -- size of the vector table (family size)
- | UnvectoredReturn Int -- family size
-
-ctrlReturnConvAlg :: TyCon -> CtrlReturnConvention
-ctrlReturnConvAlg tycon
- = case (tyConFamilySize tycon) of
- size -> -- we're supposed to know...
- if (size > (1::Int) && size <= mAX_FAMILY_SIZE_FOR_VEC_RETURNS) then
- VectoredReturn size
- else
- UnvectoredReturn size
- -- NB: unvectored returns Include size 0 (no constructors), so that
- -- the following perverse code compiles (it crashed GHC in 5.02)
- -- data T1
- -- data T2 = T2 !T1 Int
- -- The only value of type T1 is bottom, which never returns anyway.
-
dataReturnConvPrim :: CgRep -> CmmReg
-dataReturnConvPrim PtrArg = CmmGlobal (VanillaReg 1)
-dataReturnConvPrim NonPtrArg = CmmGlobal (VanillaReg 1)
+dataReturnConvPrim PtrArg = CmmGlobal (VanillaReg 1 VGcPtr)
+dataReturnConvPrim NonPtrArg = CmmGlobal (VanillaReg 1 VNonGcPtr)
dataReturnConvPrim LongArg = CmmGlobal (LongReg 1)
dataReturnConvPrim FloatArg = CmmGlobal (FloatReg 1)
dataReturnConvPrim DoubleArg = CmmGlobal (DoubleReg 1)
-- getSequelAmode returns an amode which refers to an info table. The info
--- table will always be of the RET(_VEC)?_(BIG|SMALL) kind. We're careful
+-- table will always be of the RET_(BIG|SMALL) kind. We're careful
-- not to handle real code pointers, just in case we're compiling for
-- an unregisterised/untailcallish architecture, where info pointers and
-- code pointers aren't the same.
= do { EndOfBlockInfo virt_sp sequel <- getEndOfBlockInfo
; case sequel of
OnStack -> do { sp_rel <- getSpRelOffset virt_sp
- ; returnFC (CmmLoad sp_rel wordRep) }
+ ; returnFC (CmmLoad sp_rel bWord) }
- UpdateCode -> returnFC (CmmLit (CmmLabel mkUpdInfoLabel))
- CaseAlts lbl _ _ True -> returnFC (CmmLit (CmmLabel mkSeqInfoLabel))
- CaseAlts lbl _ _ False -> returnFC (CmmLit (CmmLabel lbl))
+ UpdateCode -> returnFC (CmmLit (CmmLabel mkUpdInfoLabel))
+ CaseAlts lbl _ _ -> returnFC (CmmLit (CmmLabel lbl))
}
-------------------------------------------------------------------------
--
--- Build a liveness mask for the current stack
---
--------------------------------------------------------------------------
-
--- There are four kinds of things on the stack:
---
--- - pointer variables (bound in the environment)
--- - non-pointer variables (boudn in the environment)
--- - free slots (recorded in the stack free list)
--- - non-pointer data slots (recorded in the stack free list)
---
--- We build up a bitmap of non-pointer slots by searching the environment
--- for all the pointer variables, and subtracting these from a bitmap
--- with initially all bits set (up to the size of the stack frame).
-
-buildContLiveness :: Name -- Basis for label (only)
- -> [VirtualSpOffset] -- Live stack slots
- -> FCode Liveness
-buildContLiveness name live_slots
- = do { stk_usg <- getStkUsage
- ; let StackUsage { realSp = real_sp,
- frameSp = frame_sp } = stk_usg
-
- start_sp :: VirtualSpOffset
- start_sp = real_sp - retAddrSizeW
- -- In a continuation, we want a liveness mask that
- -- starts from just after the return address, which is
- -- on the stack at real_sp.
-
- frame_size :: WordOff
- frame_size = start_sp - frame_sp
- -- real_sp points to the frame-header for the current
- -- stack frame, and the end of this frame is frame_sp.
- -- The size is therefore real_sp - frame_sp - retAddrSizeW
- -- (subtract one for the frame-header = return address).
-
- rel_slots :: [WordOff]
- rel_slots = sortLe (<=)
- [ start_sp - ofs -- Get slots relative to top of frame
- | ofs <- live_slots ]
-
- bitmap = intsToReverseBitmap frame_size rel_slots
-
- ; WARN( not (all (>=0) rel_slots),
- ppr name $$ ppr live_slots $$ ppr frame_size $$ ppr start_sp $$ ppr rel_slots )
- mkLiveness name frame_size bitmap }
-
-
--------------------------------------------------------------------------
---
-- Register assignment
--
-------------------------------------------------------------------------
-- For primops, *all* arguments must be passed in registers
assignReturnRegs args
- = assign_regs args (mkRegTbl [])
+ -- when we have a single non-void component to return, use the normal
+ -- unpointed return convention. This make various things simpler: it
+ -- means we can assume a consistent convention for IO, which is useful
+ -- when writing code that relies on knowing the IO return convention in
+ -- the RTS (primops, especially exception-related primops).
+ -- Also, the bytecode compiler assumes this when compiling
+ -- case expressions and ccalls, so it only needs to know one set of
+ -- return conventions.
+ | [(rep,arg)] <- non_void_args, CmmGlobal r <- dataReturnConvPrim rep
+ = ([(arg, r)], [])
+ | otherwise
+ = assign_regs args (mkRegTbl [])
-- For returning unboxed tuples etc,
-- we use all regs
+ where
+ non_void_args = filter ((/= VoidArg).fst) args
assign_regs :: [(CgRep,a)] -- Arg or result values to assign
-> AvailRegs -- Regs still avail: Vanilla, Float, Double, Longs
where
go [] acc supply = (acc, []) -- Return the results reversed (doesn't matter)
go ((VoidArg,_) : args) acc supply -- Skip void arguments; they aren't passed, and
- = go args acc supply -- there's nothign to bind them to
+ = go args acc supply -- there's nothing to bind them to
go ((rep,arg) : args) acc supply
= case assign_reg rep supply of
Just (reg, supply') -> go args ((arg,reg):acc) supply'
assign_reg :: CgRep -> AvailRegs -> Maybe (GlobalReg, AvailRegs)
assign_reg FloatArg (vs, f:fs, ds, ls) = Just (FloatReg f, (vs, fs, ds, ls))
assign_reg DoubleArg (vs, fs, d:ds, ls) = Just (DoubleReg d, (vs, fs, ds, ls))
-assign_reg LongArg (vs, fs, ds, l:ls) = Just (LongReg l, (vs, fs, ds, ls))
-assign_reg PtrArg (v:vs, fs, ds, ls) = Just (VanillaReg v, (vs, fs, ds, ls))
-assign_reg NonPtrArg (v:vs, fs, ds, ls) = Just (VanillaReg v, (vs, fs, ds, ls))
+assign_reg LongArg (vs, fs, ds, l:ls) = pprTrace "longArg" (ppr l) $ Just (LongReg l, (vs, fs, ds, ls))
+assign_reg PtrArg (v:vs, fs, ds, ls) = Just (VanillaReg v VGcPtr, (vs, fs, ds, ls))
+assign_reg NonPtrArg (v:vs, fs, ds, ls) = Just (VanillaReg v VNonGcPtr, (vs, fs, ds, ls))
-- PtrArg and NonPtrArg both go in a vanilla register
assign_reg other not_enough_regs = Nothing
mkRegTbl' regs_in_use vanillas floats doubles longs
= (ok_vanilla, ok_float, ok_double, ok_long)
where
- ok_vanilla = mapCatMaybes (select VanillaReg) vanillas
+ ok_vanilla = mapCatMaybes (select (\i -> VanillaReg i VNonGcPtr)) vanillas
+ -- ptrhood isn't looked at, hence we can use any old rep.
ok_float = mapCatMaybes (select FloatReg) floats
ok_double = mapCatMaybes (select DoubleReg) doubles
ok_long = mapCatMaybes (select LongReg) longs
- -- rep isn't looked at, hence we can use any old rep.
select :: (Int -> GlobalReg) -> Int{-cand-} -> Maybe Int
-- one we've unboxed the Int, we make a GlobalReg
projects / ghc-hetmet.git / blobdiff