X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FnativeGen%2FAsmCodeGen.lhs;h=92a8bc26184b33fa8f3f987fe2a7b6e9180c11de;hb=5819de0c5d78effa16e4c59987268eadb96b8d1d;hp=d5926765b43a0ffbd8409bf60bd5bdc57832d6cb;hpb=f810b7273ec4329665e2f84fa2a78b5438e73a08;p=ghc-hetmet.git diff --git a/ghc/compiler/nativeGen/AsmCodeGen.lhs b/ghc/compiler/nativeGen/AsmCodeGen.lhs index d592676..92a8bc2 100644 --- a/ghc/compiler/nativeGen/AsmCodeGen.lhs +++ b/ghc/compiler/nativeGen/AsmCodeGen.lhs @@ -1,14 +1,12 @@ % -% (c) The AQUA Project, Glasgow University, 1993-1996 +% (c) The AQUA Project, Glasgow University, 1993-1998 % \begin{code} -#include "HsVersions.h" - -module AsmCodeGen ( writeRealAsm, dumpRealAsm ) where +module AsmCodeGen ( nativeCodeGen ) where -IMP_Ubiq(){-uitous-} -IMPORT_1_3(IO(Handle)) +#include "HsVersions.h" +#include "NCG.h" import MachMisc import MachRegs @@ -16,16 +14,36 @@ import MachCode import PprMach import AbsCStixGen ( genCodeAbstractC ) -import AbsCSyn ( AbstractC, MagicId ) +import AbsCSyn ( AbstractC, MagicId(..) ) +import AbsCUtils ( mkAbsCStmtList, magicIdPrimRep ) import AsmRegAlloc ( runRegAllocate ) -import OrdList ( OrdList ) -import PrimOp ( commutableOp, PrimOp(..) ) -import PrimRep ( PrimRep{-instance Eq-} ) -import RegAllocInfo ( mkMRegsState, MRegsState ) -import Stix ( StixTree(..), StixReg(..), CodeSegment ) -import UniqSupply ( returnUs, thenUs, mapUs, SYN_IE(UniqSM), UniqSupply ) -import Outputable ( printDoc ) -import Pretty ( Doc, vcat, Mode(..) ) +import MachOp ( MachOp(..), isCommutableMachOp, isComparisonMachOp ) +import RegAllocInfo ( findReservedRegs ) +import Stix ( StixReg(..), StixStmt(..), StixExpr(..), StixVReg(..), + pprStixStmts, pprStixStmt, + stixStmt_CountTempUses, stixStmt_Subst, + liftStrings, + initNat, + mkNatM_State, + uniqOfNatM_State, deltaOfNatM_State, + importsOfNatM_State ) +import UniqSupply ( returnUs, thenUs, initUs, + UniqSM, UniqSupply, + lazyMapUs ) +import MachMisc ( IF_ARCH_i386(i386_insert_ffrees,) ) +#if darwin_TARGET_OS +import PprMach ( pprDyldSymbolStub ) +import List ( group, sort ) +#endif + +import qualified Pretty +import Outputable +import FastString + +-- DEBUGGING ONLY +--import OrdList + +import List ( intersperse ) \end{code} The 96/03 native-code generator has machine-independent and @@ -33,9 +51,9 @@ machine-dependent modules (those \tr{#include}'ing \tr{NCG.h}). This module (@AsmCodeGen@) is the top-level machine-independent module. It uses @AbsCStixGen.genCodeAbstractC@ to produce @StixTree@s -(defined in module @Stix@), using support code from @StixInfo@ (info -tables), @StixPrim@ (primitive operations), @StixMacro@ (Abstract C -macros), and @StixInteger@ (GMP arbitrary-precision operations). +(defined in module @Stix@), using support code from @StixPrim@ +(primitive operations), @StixMacro@ (Abstract C macros), and +@StixInteger@ (GMP arbitrary-precision operations). Before entering machine-dependent land, we do some machine-independent @genericOpt@imisations (defined below) on the @StixTree@s. @@ -74,55 +92,98 @@ The machine-dependent bits break down as follows: \end{description} So, here we go: -\begin{code} -writeRealAsm :: Handle -> AbstractC -> UniqSupply -> IO () -writeRealAsm handle absC us - = _scc_ "writeRealAsm" (printDoc LeftMode handle (runNCG absC us)) - -dumpRealAsm :: AbstractC -> UniqSupply -> Doc -dumpRealAsm = runNCG - -runNCG absC - = genCodeAbstractC absC `thenUs` \ treelists -> - let - stix = map (map genericOpt) treelists - in - codeGen stix -\end{code} -@codeGen@ is the top-level code-generation function: \begin{code} -codeGen :: [[StixTree]] -> UniqSM Doc - -codeGen trees - = mapUs genMachCode trees `thenUs` \ dynamic_codes -> - let - static_instrs = scheduleMachCode dynamic_codes - in - returnUs (vcat (map pprInstr static_instrs)) +nativeCodeGen :: AbstractC -> UniqSupply -> (SDoc, Pretty.Doc) +nativeCodeGen absC us + = let absCstmts = mkAbsCStmtList absC + (results, us1) = initUs us (lazyMapUs absCtoNat absCstmts) + stix_sdocs = [ stix | (stix, insn, imports) <- results ] + insn_sdocs = [ insn | (stix, insn, imports) <- results ] + imports = [ imports | (stix, insn, imports) <- results ] + + insn_sdoc = my_vcat insn_sdocs IF_OS_darwin(Pretty.$$ dyld_stubs,) + stix_sdoc = vcat stix_sdocs + +#if darwin_TARGET_OS + -- Generate "symbol stubs" for all external symbols that might + -- come from a dynamic library. + + dyld_stubs = Pretty.vcat $ map pprDyldSymbolStub $ + map head $ group $ sort $ concat imports +#endif + +# ifdef NCG_DEBUG + my_trace m x = trace m x + my_vcat sds = Pretty.vcat ( + intersperse ( + Pretty.char ' ' + Pretty.$$ Pretty.ptext SLIT("# ___ncg_debug_marker") + Pretty.$$ Pretty.char ' ' + ) + sds + ) +# else + my_vcat sds = Pretty.vcat sds + my_trace m x = x +# endif + in + my_trace "nativeGen: begin" + (stix_sdoc, insn_sdoc) + + +absCtoNat :: AbstractC -> UniqSM (SDoc, Pretty.Doc, [FastString]) +absCtoNat absC + = _scc_ "genCodeAbstractC" genCodeAbstractC absC `thenUs` \ stixRaw -> + _scc_ "genericOpt" genericOpt stixRaw `bind` \ stixOpt -> + _scc_ "liftStrings" liftStrings stixOpt `thenUs` \ stixLifted -> + _scc_ "genMachCode" genMachCode stixLifted `thenUs` \ (pre_regalloc, imports) -> + _scc_ "regAlloc" regAlloc pre_regalloc `bind` \ almost_final -> + _scc_ "x86fp_kludge" x86fp_kludge almost_final `bind` \ final_mach_code -> + _scc_ "vcat" Pretty.vcat (map pprInstr final_mach_code) `bind` \ final_sdoc -> + _scc_ "pprStixTrees" pprStixStmts stixOpt `bind` \ stix_sdoc -> + returnUs ({-\_ -> Pretty.vcat (map pprInstr almost_final),-} + stix_sdoc, final_sdoc, imports) + where + bind f x = x f + + x86fp_kludge :: [Instr] -> [Instr] + x86fp_kludge = IF_ARCH_i386(i386_insert_ffrees,id) + + regAlloc :: InstrBlock -> [Instr] + regAlloc = runRegAllocate allocatableRegs findReservedRegs \end{code} -Top level code generator for a chunk of stix code: -\begin{code} -genMachCode :: [StixTree] -> UniqSM InstrList +Top level code generator for a chunk of stix code. For this part of +the computation, we switch from the UniqSM monad to the NatM monad. +The latter carries not only a Unique, but also an Int denoting the +current C stack pointer offset in the generated code; this is needed +for creating correct spill offsets on architectures which don't offer, +or for which it would be prohibitively expensive to employ, a frame +pointer register. Viz, x86. -genMachCode stmts - = mapUs stmt2Instrs stmts `thenUs` \ blocks -> - returnUs (foldr (.) id blocks asmVoid) -\end{code} +The offset is measured in bytes, and indicates the difference between +the current (simulated) C stack-ptr and the value it was at the +beginning of the block. For stacks which grow down, this value should +be either zero or negative. -The next bit does the code scheduling. The scheduler must also deal -with register allocation of temporaries. Much parallelism can be -exposed via the OrdList, but more might occur, so further analysis -might be needed. +Switching between the two monads whilst carrying along the same Unique +supply breaks abstraction. Is that bad? \begin{code} -scheduleMachCode :: [InstrList] -> [Instr] - -scheduleMachCode - = concat . map (runRegAllocate freeRegsState reservedRegs) - where - freeRegsState = mkMRegsState (extractMappedRegNos freeRegs) +genMachCode :: [StixStmt] -> UniqSM (InstrBlock, [FastString]) + +genMachCode stmts initial_us + = let initial_st = mkNatM_State initial_us 0 + (instr_list, final_st) = initNat initial_st (stmtsToInstrs stmts) + final_us = uniqOfNatM_State final_st + final_delta = deltaOfNatM_State final_st + final_imports = importsOfNatM_State final_st + in + if final_delta == 0 + then ((instr_list, final_imports), final_us) + else pprPanic "genMachCode: nonzero final delta" + (int final_delta) \end{code} %************************************************************************ @@ -142,91 +203,151 @@ have introduced some new opportunities for constant-folding wrt address manipulations. \begin{code} -genericOpt :: StixTree -> StixTree -\end{code} - -For most nodes, just optimize the children. +genericOpt :: [StixStmt] -> [StixStmt] +genericOpt = map stixStmt_ConFold . stixPeep -\begin{code} -genericOpt (StInd pk addr) = StInd pk (genericOpt addr) -genericOpt (StAssign pk dst src) - = StAssign pk (genericOpt dst) (genericOpt src) -genericOpt (StJump addr) = StJump (genericOpt addr) +stixPeep :: [StixStmt] -> [StixStmt] -genericOpt (StCondJump addr test) - = StCondJump addr (genericOpt test) +-- This transformation assumes that the temp assigned to in t1 +-- is not assigned to in t2; for otherwise the target of the +-- second assignment would be substituted for, giving nonsense +-- code. As far as I can see, StixTemps are only ever assigned +-- to once. It would be nice to be sure! -genericOpt (StCall fn pk args) - = StCall fn pk (map genericOpt args) -\end{code} - -Fold indices together when the types match: -\begin{code} -genericOpt (StIndex pk (StIndex pk' base off) off') - | pk == pk' - = StIndex pk (genericOpt base) - (genericOpt (StPrim IntAddOp [off, off'])) +stixPeep ( t1@(StAssignReg pka (StixTemp (StixVReg u pk)) rhs) + : t2 + : ts ) + | stixStmt_CountTempUses u t2 == 1 + && sum (map (stixStmt_CountTempUses u) ts) == 0 + = +# ifdef NCG_DEBUG + trace ("nativeGen: inlining " ++ showSDoc (pprStixExpr rhs)) +# endif + (stixPeep (stixStmt_Subst u rhs t2 : ts)) -genericOpt (StIndex pk base off) - = StIndex pk (genericOpt base) (genericOpt off) +stixPeep (t1:t2:ts) = t1 : stixPeep (t2:ts) +stixPeep [t1] = [t1] +stixPeep [] = [] \end{code} -For PrimOps, we first optimize the children, and then we try our hand -at some constant-folding. - -\begin{code} -genericOpt (StPrim op args) = primOpt op (map genericOpt args) -\end{code} - -Replace register leaves with appropriate StixTrees for the given -target. +For most nodes, just optimize the children. \begin{code} -genericOpt leaf@(StReg (StixMagicId id)) - = case (stgReg id) of - Always tree -> genericOpt tree - Save _ -> leaf - -genericOpt other = other +stixExpr_ConFold :: StixExpr -> StixExpr +stixStmt_ConFold :: StixStmt -> StixStmt + +stixStmt_ConFold stmt + = case stmt of + StAssignReg pk reg@(StixTemp _) src + -> StAssignReg pk reg (stixExpr_ConFold src) + StAssignReg pk reg@(StixMagicId mid) src + -- Replace register leaves with appropriate StixTrees for + -- the given target. MagicIds which map to a reg on this arch are left unchanged. + -- Assigning to BaseReg is always illegal, so we check for that. + -> case mid of { + BaseReg -> panic "stixStmt_ConFold: assignment to BaseReg"; + other -> + case get_MagicId_reg_or_addr mid of + Left realreg + -> StAssignReg pk reg (stixExpr_ConFold src) + Right baseRegAddr + -> stixStmt_ConFold (StAssignMem pk baseRegAddr src) + } + StAssignMem pk addr src + -> StAssignMem pk (stixExpr_ConFold addr) (stixExpr_ConFold src) + StVoidable expr + -> StVoidable (stixExpr_ConFold expr) + StJump dsts addr + -> StJump dsts (stixExpr_ConFold addr) + StCondJump addr test + -> let test_opt = stixExpr_ConFold test + in + if manifestlyZero test_opt + then StComment (mkFastString ("deleted: " ++ showSDoc (pprStixStmt stmt))) + else StCondJump addr (stixExpr_ConFold test) + StData pk datas + -> StData pk (map stixExpr_ConFold datas) + other + -> other + where + manifestlyZero (StInt 0) = True + manifestlyZero other = False + +stixExpr_ConFold expr + = case expr of + StInd pk addr + -> StInd pk (stixExpr_ConFold addr) + StCall fn cconv pk args + -> StCall fn cconv pk (map stixExpr_ConFold args) + StIndex pk (StIndex pk' base off) off' + -- Fold indices together when the types match: + | pk == pk' + -> StIndex pk (stixExpr_ConFold base) + (stixExpr_ConFold (StMachOp MO_Nat_Add [off, off'])) + StIndex pk base off + -> StIndex pk (stixExpr_ConFold base) (stixExpr_ConFold off) + + StMachOp mop args + -- For PrimOps, we first optimize the children, and then we try + -- our hand at some constant-folding. + -> stixMachOpFold mop (map stixExpr_ConFold args) + StReg (StixMagicId mid) + -- Replace register leaves with appropriate StixTrees for + -- the given target. MagicIds which map to a reg on this arch are left unchanged. + -- For the rest, BaseReg is taken to mean the address of the reg table + -- in MainCapability, and for all others we generate an indirection to + -- its location in the register table. + -> case get_MagicId_reg_or_addr mid of + Left realreg -> expr + Right baseRegAddr + -> case mid of + BaseReg -> stixExpr_ConFold baseRegAddr + other -> stixExpr_ConFold (StInd (magicIdPrimRep mid) baseRegAddr) + other + -> other \end{code} Now, try to constant-fold the PrimOps. The arguments have already been optimized and folded. \begin{code} -primOpt - :: PrimOp -- The operation from an StPrim - -> [StixTree] -- The optimized arguments - -> StixTree - -primOpt op arg@[StInt x] - = case op of - IntNegOp -> StInt (-x) - IntAbsOp -> StInt (abs x) - _ -> StPrim op arg - -primOpt op args@[StInt x, StInt y] - = case op of - CharGtOp -> StInt (if x > y then 1 else 0) - CharGeOp -> StInt (if x >= y then 1 else 0) - CharEqOp -> StInt (if x == y then 1 else 0) - CharNeOp -> StInt (if x /= y then 1 else 0) - CharLtOp -> StInt (if x < y then 1 else 0) - CharLeOp -> StInt (if x <= y then 1 else 0) - IntAddOp -> StInt (x + y) - IntSubOp -> StInt (x - y) - IntMulOp -> StInt (x * y) - IntQuotOp -> StInt (x `quot` y) - IntRemOp -> StInt (x `rem` y) - IntGtOp -> StInt (if x > y then 1 else 0) - IntGeOp -> StInt (if x >= y then 1 else 0) - IntEqOp -> StInt (if x == y then 1 else 0) - IntNeOp -> StInt (if x /= y then 1 else 0) - IntLtOp -> StInt (if x < y then 1 else 0) - IntLeOp -> StInt (if x <= y then 1 else 0) - _ -> StPrim op args +stixMachOpFold + :: MachOp -- The operation from an StMachOp + -> [StixExpr] -- The optimized arguments + -> StixExpr + +stixMachOpFold mop arg@[StInt x] + = case mop of + MO_NatS_Neg -> StInt (-x) + other -> StMachOp mop arg + +stixMachOpFold mop args@[StInt x, StInt y] + = case mop of + MO_32U_Gt -> StInt (if x > y then 1 else 0) + MO_32U_Ge -> StInt (if x >= y then 1 else 0) + MO_32U_Eq -> StInt (if x == y then 1 else 0) + MO_32U_Ne -> StInt (if x /= y then 1 else 0) + MO_32U_Lt -> StInt (if x < y then 1 else 0) + MO_32U_Le -> StInt (if x <= y then 1 else 0) + MO_Nat_Add -> StInt (x + y) + MO_Nat_Sub -> StInt (x - y) + MO_NatS_Mul -> StInt (x * y) + MO_NatS_Quot | y /= 0 -> StInt (x `quot` y) + MO_NatS_Rem | y /= 0 -> StInt (x `rem` y) + MO_NatS_Gt -> StInt (if x > y then 1 else 0) + MO_NatS_Ge -> StInt (if x >= y then 1 else 0) + MO_Nat_Eq -> StInt (if x == y then 1 else 0) + MO_Nat_Ne -> StInt (if x /= y then 1 else 0) + MO_NatS_Lt -> StInt (if x < y then 1 else 0) + MO_NatS_Le -> StInt (if x <= y then 1 else 0) + MO_Nat_Shl | y >= 0 && y < 32 -> do_shl x y + other -> StMachOp mop args + where + do_shl :: Integer -> Integer -> StixExpr + do_shl v 0 = StInt v + do_shl v n | n > 0 = do_shl (v*2) (n-1) \end{code} When possible, shift the constants to the right-hand side, so that we @@ -235,51 +356,65 @@ also assume that constants have been shifted to the right when possible. \begin{code} -primOpt op [x@(StInt _), y] | commutableOp op = primOpt op [y, x] +stixMachOpFold op [x@(StInt _), y] | isCommutableMachOp op + = stixMachOpFold op [y, x] \end{code} We can often do something with constants of 0 and 1 ... \begin{code} -primOpt op args@[x, y@(StInt 0)] - = case op of - IntAddOp -> x - IntSubOp -> x - IntMulOp -> y - AndOp -> y - OrOp -> x - SllOp -> x - SraOp -> x - SrlOp -> x - ISllOp -> x - ISraOp -> x - ISrlOp -> x - _ -> StPrim op args - -primOpt op args@[x, y@(StInt 1)] - = case op of - IntMulOp -> x - IntQuotOp -> x - IntRemOp -> StInt 0 - _ -> StPrim op args +stixMachOpFold mop args@[x, y@(StInt 0)] + = case mop of + MO_Nat_Add -> x + MO_Nat_Sub -> x + MO_NatS_Mul -> y + MO_NatU_Mul -> y + MO_Nat_And -> y + MO_Nat_Or -> x + MO_Nat_Xor -> x + MO_Nat_Shl -> x + MO_Nat_Shr -> x + MO_Nat_Sar -> x + MO_Nat_Ne | x_is_comparison -> x + other -> StMachOp mop args + where + x_is_comparison + = case x of + StMachOp mopp [_, _] -> isComparisonMachOp mopp + _ -> False + +stixMachOpFold mop args@[x, y@(StInt 1)] + = case mop of + MO_NatS_Mul -> x + MO_NatU_Mul -> x + MO_NatS_Quot -> x + MO_NatU_Quot -> x + MO_NatS_Rem -> StInt 0 + MO_NatU_Rem -> StInt 0 + other -> StMachOp mop args \end{code} Now look for multiplication/division by powers of 2 (integers). \begin{code} -primOpt op args@[x, y@(StInt n)] - = case op of - IntMulOp -> case exactLog2 n of - Nothing -> StPrim op args - Just p -> StPrim SllOp [x, StInt p] - IntQuotOp -> case exactLog2 n of - Nothing -> StPrim op args - Just p -> StPrim SraOp [x, StInt p] - _ -> StPrim op args +stixMachOpFold mop args@[x, y@(StInt n)] + = case mop of + MO_NatS_Mul + -> case exactLog2 n of + Nothing -> unchanged + Just p -> StMachOp MO_Nat_Shl [x, StInt p] + MO_NatS_Quot + -> case exactLog2 n of + Nothing -> unchanged + Just p -> StMachOp MO_Nat_Shr [x, StInt p] + other + -> unchanged + where + unchanged = StMachOp mop args \end{code} Anything else is just too hard. \begin{code} -primOpt op args = StPrim op args +stixMachOpFold mop args = StMachOp mop args \end{code}