diff options
Diffstat (limited to 'compiler/GHC/CmmToAsm/PIC.hs')
| -rw-r--r-- | compiler/GHC/CmmToAsm/PIC.hs | 298 |
1 files changed, 154 insertions, 144 deletions
diff --git a/compiler/GHC/CmmToAsm/PIC.hs b/compiler/GHC/CmmToAsm/PIC.hs index 323d93d173..d4d8b55e7e 100644 --- a/compiler/GHC/CmmToAsm/PIC.hs +++ b/compiler/GHC/CmmToAsm/PIC.hs @@ -57,6 +57,7 @@ import GHC.Platform import GHC.CmmToAsm.Instr import GHC.Platform.Reg import GHC.CmmToAsm.Monad +import GHC.CmmToAsm.Config import GHC.Cmm.Dataflow.Collections @@ -163,7 +164,7 @@ cmmMakePicReference dflags lbl | OSAIX <- platformOS $ targetPlatform dflags = CmmMachOp (MO_Add W32) [ CmmReg (CmmGlobal PicBaseReg) - , CmmLit $ picRelative dflags + , CmmLit $ picRelative (wordWidth dflags) (platformArch $ targetPlatform dflags) (platformOS $ targetPlatform dflags) lbl ] @@ -172,7 +173,7 @@ cmmMakePicReference dflags lbl | ArchPPC_64 _ <- platformArch $ targetPlatform dflags = CmmMachOp (MO_Add W32) -- code model medium [ CmmReg (CmmGlobal PicBaseReg) - , CmmLit $ picRelative dflags + , CmmLit $ picRelative (wordWidth dflags) (platformArch $ targetPlatform dflags) (platformOS $ targetPlatform dflags) lbl ] @@ -181,7 +182,7 @@ cmmMakePicReference dflags lbl && absoluteLabel lbl = CmmMachOp (MO_Add (wordWidth dflags)) [ CmmReg (CmmGlobal PicBaseReg) - , CmmLit $ picRelative dflags + , CmmLit $ picRelative (wordWidth dflags) (platformArch $ targetPlatform dflags) (platformOS $ targetPlatform dflags) lbl ] @@ -404,7 +405,7 @@ howToAccessLabel dflags _ _ _ _ _ -- | Says what we have to add to our 'PIC base register' in order to -- get the address of a label. -picRelative :: DynFlags -> Arch -> OS -> CLabel -> CmmLit +picRelative :: Width -> Arch -> OS -> CLabel -> CmmLit -- Darwin, but not x86_64: -- The PIC base register points to the PIC base label at the beginning @@ -413,15 +414,15 @@ picRelative :: DynFlags -> Arch -> OS -> CLabel -> CmmLit -- We have already made sure that all labels that are not from the current -- module are accessed indirectly ('as' can't calculate differences between -- undefined labels). -picRelative dflags arch OSDarwin lbl +picRelative width arch OSDarwin lbl | arch /= ArchX86_64 - = CmmLabelDiffOff lbl mkPicBaseLabel 0 (wordWidth dflags) + = CmmLabelDiffOff lbl mkPicBaseLabel 0 width -- On AIX we use an indirect local TOC anchored by 'gotLabel'. -- This way we use up only one global TOC entry per compilation-unit -- (this is quite similar to GCC's @-mminimal-toc@ compilation mode) -picRelative dflags _ OSAIX lbl - = CmmLabelDiffOff lbl gotLabel 0 (wordWidth dflags) +picRelative width _ OSAIX lbl + = CmmLabelDiffOff lbl gotLabel 0 width -- PowerPC Linux: -- The PIC base register points to our fake GOT. Use a label difference @@ -429,9 +430,9 @@ picRelative dflags _ OSAIX lbl -- We have made sure that *everything* is accessed indirectly, so this -- is only used for offsets from the GOT to symbol pointers inside the -- GOT. -picRelative dflags ArchPPC os lbl +picRelative width ArchPPC os lbl | osElfTarget os - = CmmLabelDiffOff lbl gotLabel 0 (wordWidth dflags) + = CmmLabelDiffOff lbl gotLabel 0 width -- Most Linux versions: @@ -453,14 +454,14 @@ picRelative _ arch os lbl in result picRelative _ _ _ _ - = panic "PositionIndependentCode.picRelative undefined for this platform" + = panic "GHC.CmmToAsm.PIC.picRelative undefined for this platform" -------------------------------------------------------------------------------- -needImportedSymbols :: DynFlags -> Arch -> OS -> Bool -needImportedSymbols dflags arch os +needImportedSymbols :: NCGConfig -> Bool +needImportedSymbols config | os == OSDarwin , arch /= ArchX86_64 = True @@ -471,7 +472,7 @@ needImportedSymbols dflags arch os -- PowerPC Linux: -fPIC or -dynamic | osElfTarget os , arch == ArchPPC - = positionIndependent dflags || gopt Opt_ExternalDynamicRefs dflags + = ncgPIC config || ncgExternalDynamicRefs config -- PowerPC 64 Linux: always | osElfTarget os @@ -481,11 +482,15 @@ needImportedSymbols dflags arch os -- i386 (and others?): -dynamic but not -fPIC | osElfTarget os , arch /= ArchPPC_64 ELF_V1 && arch /= ArchPPC_64 ELF_V2 - = gopt Opt_ExternalDynamicRefs dflags && - not (positionIndependent dflags) + = ncgExternalDynamicRefs config && + not (ncgPIC config) | otherwise = False + where + platform = ncgPlatform config + arch = platformArch platform + os = platformOS platform -- gotLabel -- The label used to refer to our "fake GOT" from @@ -499,13 +504,16 @@ gotLabel --------------------------------------------------------------------------------- +-- Emit GOT declaration +-- Output whatever needs to be output once per .s file. +-- -- We don't need to declare any offset tables. -- However, for PIC on x86, we need a small helper function. -pprGotDeclaration :: DynFlags -> Arch -> OS -> SDoc -pprGotDeclaration dflags ArchX86 OSDarwin - | positionIndependent dflags - = vcat [ +pprGotDeclaration :: NCGConfig -> SDoc +pprGotDeclaration config = case (arch,os) of + (ArchX86, OSDarwin) + | ncgPIC config + -> vcat [ text ".section __TEXT,__textcoal_nt,coalesced,no_toc", text ".weak_definition ___i686.get_pc_thunk.ax", text ".private_extern ___i686.get_pc_thunk.ax", @@ -513,48 +521,49 @@ pprGotDeclaration dflags ArchX86 OSDarwin text "\tmovl (%esp), %eax", text "\tret" ] -pprGotDeclaration _ _ OSDarwin - = empty - --- Emit XCOFF TOC section -pprGotDeclaration _ _ OSAIX - = vcat $ [ text ".toc" - , text ".tc ghc_toc_table[TC],.LCTOC1" - , text ".csect ghc_toc_table[RW]" - -- See Note [.LCTOC1 in PPC PIC code] - , text ".set .LCTOC1,$+0x8000" - ] - - --- PPC 64 ELF v1 needs a Table Of Contents (TOC) -pprGotDeclaration _ (ArchPPC_64 ELF_V1) _ - = text ".section \".toc\",\"aw\"" --- In ELF v2 we also need to tell the assembler that we want ABI --- version 2. This would normally be done at the top of the file --- right after a file directive, but I could not figure out how --- to do that. -pprGotDeclaration _ (ArchPPC_64 ELF_V2) _ - = vcat [ text ".abiversion 2", - text ".section \".toc\",\"aw\"" - ] + (_, OSDarwin) -> empty --- Emit GOT declaration --- Output whatever needs to be output once per .s file. -pprGotDeclaration dflags arch os + -- Emit XCOFF TOC section + (_, OSAIX) + -> vcat $ [ text ".toc" + , text ".tc ghc_toc_table[TC],.LCTOC1" + , text ".csect ghc_toc_table[RW]" + -- See Note [.LCTOC1 in PPC PIC code] + , text ".set .LCTOC1,$+0x8000" + ] + + + -- PPC 64 ELF v1 needs a Table Of Contents (TOC) + (ArchPPC_64 ELF_V1, _) + -> text ".section \".toc\",\"aw\"" + + -- In ELF v2 we also need to tell the assembler that we want ABI + -- version 2. This would normally be done at the top of the file + -- right after a file directive, but I could not figure out how + -- to do that. + (ArchPPC_64 ELF_V2, _) + -> vcat [ text ".abiversion 2", + text ".section \".toc\",\"aw\"" + ] + + (arch, os) | osElfTarget os , arch /= ArchPPC_64 ELF_V1 && arch /= ArchPPC_64 ELF_V2 - , not (positionIndependent dflags) - = empty + , not (ncgPIC config) + -> empty | osElfTarget os , arch /= ArchPPC_64 ELF_V1 && arch /= ArchPPC_64 ELF_V2 - = vcat [ + -> vcat [ -- See Note [.LCTOC1 in PPC PIC code] text ".section \".got2\",\"aw\"", text ".LCTOC1 = .+32768" ] -pprGotDeclaration _ _ _ - = panic "pprGotDeclaration: no match" + _ -> panic "pprGotDeclaration: no match" + where + platform = ncgPlatform config + arch = platformArch platform + os = platformOS platform -------------------------------------------------------------------------------- @@ -563,43 +572,44 @@ pprGotDeclaration _ _ _ -- and one for non-PIC. -- -pprImportedSymbol :: DynFlags -> Platform -> CLabel -> SDoc -pprImportedSymbol dflags (Platform { platformMini = PlatformMini { platformMini_arch = ArchX86, platformMini_os = OSDarwin } }) importedLbl +pprImportedSymbol :: DynFlags -> NCGConfig -> CLabel -> SDoc +pprImportedSymbol dflags config importedLbl = case (arch,os) of + (ArchX86, OSDarwin) | Just (CodeStub, lbl) <- dynamicLinkerLabelInfo importedLbl - = case positionIndependent dflags of - False -> - vcat [ - text ".symbol_stub", - text "L" <> pprCLabel dflags lbl <> ptext (sLit "$stub:"), - text "\t.indirect_symbol" <+> pprCLabel dflags lbl, - text "\tjmp *L" <> pprCLabel dflags lbl - <> text "$lazy_ptr", - text "L" <> pprCLabel dflags lbl - <> text "$stub_binder:", - text "\tpushl $L" <> pprCLabel dflags lbl - <> text "$lazy_ptr", - text "\tjmp dyld_stub_binding_helper" - ] - True -> - vcat [ - text ".section __TEXT,__picsymbolstub2," - <> text "symbol_stubs,pure_instructions,25", - text "L" <> pprCLabel dflags lbl <> ptext (sLit "$stub:"), - text "\t.indirect_symbol" <+> pprCLabel dflags lbl, - text "\tcall ___i686.get_pc_thunk.ax", - text "1:", - text "\tmovl L" <> pprCLabel dflags lbl - <> text "$lazy_ptr-1b(%eax),%edx", - text "\tjmp *%edx", - text "L" <> pprCLabel dflags lbl - <> text "$stub_binder:", - text "\tlea L" <> pprCLabel dflags lbl - <> text "$lazy_ptr-1b(%eax),%eax", - text "\tpushl %eax", - text "\tjmp dyld_stub_binding_helper" - ] - $+$ vcat [ text ".section __DATA, __la_sym_ptr" - <> (if positionIndependent dflags then int 2 else int 3) + -> if not pic + then + vcat [ + text ".symbol_stub", + text "L" <> pprCLabel dflags lbl <> ptext (sLit "$stub:"), + text "\t.indirect_symbol" <+> pprCLabel dflags lbl, + text "\tjmp *L" <> pprCLabel dflags lbl + <> text "$lazy_ptr", + text "L" <> pprCLabel dflags lbl + <> text "$stub_binder:", + text "\tpushl $L" <> pprCLabel dflags lbl + <> text "$lazy_ptr", + text "\tjmp dyld_stub_binding_helper" + ] + else + vcat [ + text ".section __TEXT,__picsymbolstub2," + <> text "symbol_stubs,pure_instructions,25", + text "L" <> pprCLabel dflags lbl <> ptext (sLit "$stub:"), + text "\t.indirect_symbol" <+> pprCLabel dflags lbl, + text "\tcall ___i686.get_pc_thunk.ax", + text "1:", + text "\tmovl L" <> pprCLabel dflags lbl + <> text "$lazy_ptr-1b(%eax),%edx", + text "\tjmp *%edx", + text "L" <> pprCLabel dflags lbl + <> text "$stub_binder:", + text "\tlea L" <> pprCLabel dflags lbl + <> text "$lazy_ptr-1b(%eax),%eax", + text "\tpushl %eax", + text "\tjmp dyld_stub_binding_helper" + ] + $+$ vcat [ text ".section __DATA, __la_sym_ptr" + <> (if pic then int 2 else int 3) <> text ",lazy_symbol_pointers", text "L" <> pprCLabel dflags lbl <> ptext (sLit "$lazy_ptr:"), text "\t.indirect_symbol" <+> pprCLabel dflags lbl, @@ -607,71 +617,68 @@ pprImportedSymbol dflags (Platform { platformMini = PlatformMini { platformMini_ <> text "$stub_binder"] | Just (SymbolPtr, lbl) <- dynamicLinkerLabelInfo importedLbl - = vcat [ + -> vcat [ text ".non_lazy_symbol_pointer", char 'L' <> pprCLabel dflags lbl <> text "$non_lazy_ptr:", text "\t.indirect_symbol" <+> pprCLabel dflags lbl, text "\t.long\t0"] | otherwise - = empty + -> empty + (_, OSDarwin) -> empty -pprImportedSymbol _ (Platform { platformMini = PlatformMini { platformMini_os = OSDarwin } }) _ - = empty --- XCOFF / AIX --- --- Similar to PPC64 ELF v1, there's dedicated TOC register (r2). To --- workaround the limitation of a global TOC we use an indirect TOC --- with the label `ghc_toc_table`. --- --- See also GCC's `-mminimal-toc` compilation mode or --- http://www.ibm.com/developerworks/rational/library/overview-toc-aix/ --- --- NB: No DSO-support yet + -- XCOFF / AIX + -- + -- Similar to PPC64 ELF v1, there's dedicated TOC register (r2). To + -- workaround the limitation of a global TOC we use an indirect TOC + -- with the label `ghc_toc_table`. + -- + -- See also GCC's `-mminimal-toc` compilation mode or + -- http://www.ibm.com/developerworks/rational/library/overview-toc-aix/ + -- + -- NB: No DSO-support yet -pprImportedSymbol dflags (Platform { platformMini = PlatformMini { platformMini_os = OSAIX } }) importedLbl - = case dynamicLinkerLabelInfo importedLbl of + (_, OSAIX) -> case dynamicLinkerLabelInfo importedLbl of Just (SymbolPtr, lbl) -> vcat [ text "LC.." <> pprCLabel dflags lbl <> char ':', text "\t.long" <+> pprCLabel dflags lbl ] _ -> empty --- ELF / Linux --- --- In theory, we don't need to generate any stubs or symbol pointers --- by hand for Linux. --- --- Reality differs from this in two areas. --- --- 1) If we just use a dynamically imported symbol directly in a read-only --- section of the main executable (as GCC does), ld generates R_*_COPY --- relocations, which are fundamentally incompatible with reversed info --- tables. Therefore, we need a table of imported addresses in a writable --- section. --- The "official" GOT mechanism (label@got) isn't intended to be used --- in position dependent code, so we have to create our own "fake GOT" --- when not Opt_PIC && WayDyn `elem` ways dflags. --- --- 2) PowerPC Linux is just plain broken. --- While it's theoretically possible to use GOT offsets larger --- than 16 bit, the standard crt*.o files don't, which leads to --- linker errors as soon as the GOT size exceeds 16 bit. --- Also, the assembler doesn't support @gotoff labels. --- In order to be able to use a larger GOT, we have to circumvent the --- entire GOT mechanism and do it ourselves (this is also what GCC does). - - --- When needImportedSymbols is defined, --- the NCG will keep track of all DynamicLinkerLabels it uses --- and output each of them using pprImportedSymbol. - -pprImportedSymbol dflags platform@(Platform { platformMini = PlatformMini { platformMini_arch = ArchPPC_64 _ } }) - importedLbl - | osElfTarget (platformOS platform) - = case dynamicLinkerLabelInfo importedLbl of + -- ELF / Linux + -- + -- In theory, we don't need to generate any stubs or symbol pointers + -- by hand for Linux. + -- + -- Reality differs from this in two areas. + -- + -- 1) If we just use a dynamically imported symbol directly in a read-only + -- section of the main executable (as GCC does), ld generates R_*_COPY + -- relocations, which are fundamentally incompatible with reversed info + -- tables. Therefore, we need a table of imported addresses in a writable + -- section. + -- The "official" GOT mechanism (label@got) isn't intended to be used + -- in position dependent code, so we have to create our own "fake GOT" + -- when not Opt_PIC && WayDyn `elem` ways dflags. + -- + -- 2) PowerPC Linux is just plain broken. + -- While it's theoretically possible to use GOT offsets larger + -- than 16 bit, the standard crt*.o files don't, which leads to + -- linker errors as soon as the GOT size exceeds 16 bit. + -- Also, the assembler doesn't support @gotoff labels. + -- In order to be able to use a larger GOT, we have to circumvent the + -- entire GOT mechanism and do it ourselves (this is also what GCC does). + + + -- When needImportedSymbols is defined, + -- the NCG will keep track of all DynamicLinkerLabels it uses + -- and output each of them using pprImportedSymbol. + + (ArchPPC_64 _, _) + | osElfTarget os + -> case dynamicLinkerLabelInfo importedLbl of Just (SymbolPtr, lbl) -> vcat [ text ".section \".toc\", \"aw\"", @@ -679,11 +686,10 @@ pprImportedSymbol dflags platform@(Platform { platformMini = PlatformMini { plat text "\t.quad" <+> pprCLabel dflags lbl ] _ -> empty -pprImportedSymbol dflags platform importedLbl - | osElfTarget (platformOS platform) - = case dynamicLinkerLabelInfo importedLbl of + _ | osElfTarget os + -> case dynamicLinkerLabelInfo importedLbl of Just (SymbolPtr, lbl) - -> let symbolSize = case wordWidth dflags of + -> let symbolSize = case ncgWordWidth config of W32 -> sLit "\t.long" W64 -> sLit "\t.quad" _ -> panic "Unknown wordRep in pprImportedSymbol" @@ -696,8 +702,12 @@ pprImportedSymbol dflags platform importedLbl -- PLT code stubs are generated automatically by the dynamic linker. _ -> empty -pprImportedSymbol _ _ _ - = panic "PIC.pprImportedSymbol: no match" + _ -> panic "PIC.pprImportedSymbol: no match" + where + platform = ncgPlatform config + arch = platformArch platform + os = platformOS platform + pic = ncgPIC config -------------------------------------------------------------------------------- -- Generate code to calculate the address that should be put in the |