ghc/compiler/main/CmdLineOpts.lhs

   1 %
   2 % (c) The AQUA Project, Glasgow University, 1996
   3 %
   4 \section[CmdLineOpts]{Things to do with command-line options}
   5
   6 \begin{code}
   7 #include "HsVersions.h"
   8
   9 module CmdLineOpts where
  10
  11 import PreludeGlaST     -- bad bad bad boy, Will (_Array internals)
  12 import Argv
  13
  14 CHK_Ubiq() -- debugging consistency check
  15
  16 import Maybes           ( assocMaybe, firstJust, maybeToBool, Maybe(..) )
  17 import Util             ( startsWith, panic, panic#, assertPanic )
  18 \end{code}
  19
  20 A command-line {\em switch} is (generally) either on or off; e.g., the
  21 ``verbose'' (-v) switch is either on or off.  (The \tr{-G<group>}
  22 switch is an exception; it's set to a string, or nothing.)
  23
  24 A list of {\em ToDo}s is things to be done in a particular part of
  25 processing.  A (fictitious) example for the Core-to-Core simplifier
  26 might be: run the simplifier, then run the strictness analyser, then
  27 run the simplifier again (three ``todos'').
  28
  29 There are three ``to-do processing centers'' at the moment.  In the
  30 main loop (\tr{main/Main.lhs}), in the Core-to-Core processing loop
  31 (\tr{simplCore/SimplCore.lhs), and in the STG-to-STG processing loop
  32 (\tr{simplStg/SimplStg.lhs}).
  33
  34 %************************************************************************
  35 %*                                                                      *
  36 \subsection{Datatypes associated with command-line options}
  37 %*                                                                      *
  38 %************************************************************************
  39
  40 \begin{code}
  41 data SwitchResult
  42   = SwBool      Bool            -- on/off
  43   | SwString    FAST_STRING     -- nothing or a String
  44   | SwInt       Int             -- nothing or an Int
  45 \end{code}
  46
  47 \begin{code}
  48 data CoreToDo           -- These are diff core-to-core passes,
  49                         -- which may be invoked in any order,
  50                         -- as many times as you like.
  51
  52   = CoreDoSimplify      -- The core-to-core simplifier.
  53         (SimplifierSwitch -> SwitchResult)
  54                         -- Each run of the simplifier can take a different
  55                         -- set of simplifier-specific flags.
  56   | CoreDoCalcInlinings1
  57   | CoreDoCalcInlinings2
  58   | CoreDoFloatInwards
  59   | CoreDoFullLaziness
  60   | CoreLiberateCase
  61   | CoreDoPrintCore
  62   | CoreDoStaticArgs
  63   | CoreDoStrictness
  64   | CoreDoSpecialising
  65   | CoreDoDeforest
  66   | CoreDoAutoCostCentres
  67   | CoreDoFoldrBuildWorkerWrapper
  68   | CoreDoFoldrBuildWWAnal
  69 \end{code}
  70
  71 \begin{code}
  72 data StgToDo
  73   = StgDoStaticArgs
  74   | StgDoUpdateAnalysis
  75   | StgDoLambdaLift
  76   | StgDoMassageForProfiling  -- should be (next to) last
  77   -- There's also setStgVarInfo, but its absolute "lastness"
  78   -- is so critical that it is hardwired in (no flag).
  79   | D_stg_stats
  80 \end{code}
  81
  82 \begin{code}
  83 data SimplifierSwitch
  84   = SimplOkToDupCode
  85   | SimplFloatLetsExposingWHNF
  86   | SimplOkToFloatPrimOps
  87   | SimplAlwaysFloatLetsFromLets
  88   | SimplDoCaseElim
  89   | SimplReuseCon
  90   | SimplCaseOfCase
  91   | SimplLetToCase
  92   | SimplMayDeleteConjurableIds
  93   | SimplPedanticBottoms -- see Simplifier for an explanation
  94   | SimplDoArityExpand   -- expand arity of bindings
  95   | SimplDoFoldrBuild    -- This is the per-simplification flag;
  96                          -- see also FoldrBuildOn, used elsewhere
  97                          -- in the compiler.
  98   | SimplDoInlineFoldrBuild
  99                          -- inline foldr/build (*after* f/b rule is used)
 100
 101   | IgnoreINLINEPragma
 102   | SimplDoLambdaEtaExpansion
 103   | SimplDoEtaReduction
 104
 105   | EssentialUnfoldingsOnly -- never mind the thresholds, only
 106                             -- do unfoldings that *must* be done
 107                             -- (to saturate constructors and primitives)
 108
 109   | ShowSimplifierProgress  -- report counts on every interation
 110
 111   | MaxSimplifierIterations Int
 112
 113   | SimplUnfoldingUseThreshold      Int -- per-simplification variants
 114   | SimplUnfoldingCreationThreshold Int
 115
 116   | KeepSpecPragmaIds       -- We normally *toss* Ids we can do without
 117   | KeepUnusedBindings
 118
 119   | SimplNoLetFromCase      -- used when turning off floating entirely
 120   | SimplNoLetFromApp       -- (for experimentation only) WDP 95/10
 121   | SimplNoLetFromStrictLet
 122
 123   | SimplDontFoldBackAppend
 124                         -- we fold `foldr (:)' back into flip (++),
 125                         -- but we *don't* want to do it when compiling
 126                         -- List.hs, otherwise
 127                         -- xs ++ ys = foldr (:) ys xs
 128                         -- {- via our loopback -}
 129                         -- xs ++ ys = xs ++ ys
 130                         -- Oops!
 131                         -- So only use this flag inside List.hs
 132                         -- (Sigh, what a HACK, Andy.  WDP 96/01)
 133 \end{code}
 134
 135 %************************************************************************
 136 %*                                                                      *
 137 \subsection{Classifying command-line options}
 138 %*                                                                      *
 139 %************************************************************************
 140
 141 \begin{code}
 142 lookup     :: FAST_STRING -> Bool
 143 lookup_int :: String -> Maybe Int
 144 lookup_str :: String -> Maybe String
 145
 146 lookup     sw = maybeToBool (assoc_opts sw)
 147
 148 lookup_str sw = firstJust (map (startsWith sw) unpacked_opts)
 149
 150 lookup_int sw = case (lookup_str sw) of
 151                   Nothing -> Nothing
 152                   Just xx -> Just (read xx)
 153
 154 assoc_opts    = assocMaybe [ (a, True) | a <- argv ]
 155 unpacked_opts = map _UNPK_ argv
 156 \end{code}
 157
 158 \begin{code}
 159 opt_AllDemanded                 = lookup  SLIT("-fall-demanded")
 160 opt_AllStrict                   = lookup  SLIT("-fall-strict")
 161 opt_AutoSccsOnAllToplevs        = lookup  SLIT("-fauto-sccs-on-all-toplevs")
 162 opt_AutoSccsOnExportedToplevs   = lookup  SLIT("-fauto-sccs-on-exported-toplevs")
 163 opt_AutoSccsOnIndividualCafs    = lookup  SLIT("-fauto-sccs-on-individual-cafs")
 164 opt_CompilingPrelude            = lookup  SLIT("-fcompiling-prelude")
 165 opt_D_dump_absC                 = lookup  SLIT("-ddump-absC")
 166 opt_D_dump_asm                  = lookup  SLIT("-ddump-asm")
 167 opt_D_dump_deforest             = lookup  SLIT("-ddump-deforest")
 168 opt_D_dump_deriv                = lookup  SLIT("-ddump-deriv")
 169 opt_D_dump_ds                   = lookup  SLIT("-ddump-ds")
 170 opt_D_dump_flatC                = lookup  SLIT("-ddump-flatC")
 171 opt_D_dump_occur_anal           = lookup  SLIT("-ddump-occur-anal")
 172 opt_D_dump_rdr                  = lookup  SLIT("-ddump-rdr")
 173 opt_D_dump_realC                = lookup  SLIT("-ddump-realC")
 174 opt_D_dump_rn                   = lookup  SLIT("-ddump-rn")
 175 opt_D_dump_simpl                = lookup  SLIT("-ddump-simpl")
 176 opt_D_dump_spec                 = lookup  SLIT("-ddump-spec")
 177 opt_D_dump_stg                  = lookup  SLIT("-ddump-stg")
 178 opt_D_dump_stranal              = lookup  SLIT("-ddump-stranal")
 179 opt_D_dump_tc                   = lookup  SLIT("-ddump-tc")
 180 opt_D_show_passes               = lookup  SLIT("-dshow-passes")
 181 opt_D_simplifier_stats          = lookup  SLIT("-dsimplifier-stats")
 182 opt_D_source_stats              = lookup  SLIT("-dsource-stats")
 183 opt_D_verbose_core2core         = lookup  SLIT("-dverbose-simpl")
 184 opt_D_verbose_stg2stg           = lookup  SLIT("-dverbose-stg")
 185 opt_DoCoreLinting               = lookup  SLIT("-dcore-lint")
 186 opt_DoSemiTagging               = lookup  SLIT("-fsemi-tagging")
 187 opt_DoTickyProfiling            = lookup  SLIT("-fticky-ticky")
 188 opt_FoldrBuildOn                = lookup  SLIT("-ffoldr-build-on")
 189 opt_FoldrBuildTrace             = lookup  SLIT("-ffoldr-build-trace")
 190 opt_ForConcurrent               = lookup  SLIT("-fconcurrent")
 191 opt_GranMacros                  = lookup  SLIT("-fgransim")
 192 opt_GlasgowExts                 = lookup  SLIT("-fglasgow-exts")
 193 opt_Haskell_1_3                 = lookup  SLIT("-fhaskell-1.3")
 194 opt_HideBuiltinNames            = lookup  SLIT("-fhide-builtin-names")
 195 opt_HideMostBuiltinNames        = lookup  SLIT("-fmin-builtin-names")
 196 opt_IgnoreStrictnessPragmas     = lookup  SLIT("-fignore-strictness-pragmas")
 197 opt_IrrefutableEverything       = lookup  SLIT("-firrefutable-everything")
 198 opt_IrrefutableTuples           = lookup  SLIT("-firrefutable-tuples")
 199 opt_WarnNameShadowing           = lookup  SLIT("-fwarn-name-shadowing")
 200 opt_NumbersStrict               = lookup  SLIT("-fnumbers-strict")
 201 opt_OmitBlackHoling             = lookup  SLIT("-dno-black-holing")
 202 opt_OmitDefaultInstanceMethods  = lookup  SLIT("-fomit-default-instance-methods")
 203 opt_OmitInterfacePragmas        = lookup  SLIT("-fomit-interface-pragmas")
 204 opt_PprStyle_All                = lookup  SLIT("-dppr-all")
 205 opt_PprStyle_Debug              = lookup  SLIT("-dppr-debug")
 206 opt_PprStyle_User               = lookup  SLIT("-dppr-user")
 207 opt_ReportWhyUnfoldingsDisallowed= lookup SLIT("-freport-disallowed-unfoldings")
 208 opt_SccProfilingOn              = lookup  SLIT("-fscc-profiling")
 209 opt_ShowImportSpecs             = lookup  SLIT("-fshow-import-specs")
 210 opt_ShowPragmaNameErrs          = lookup  SLIT("-fshow-pragma-name-errs")
 211 opt_SigsRequired                = lookup  SLIT("-fsignatures-required")
 212 opt_SpecialiseAll               = lookup  SLIT("-fspecialise-all")
 213 opt_SpecialiseImports           = lookup  SLIT("-fspecialise-imports")
 214 opt_SpecialiseOverloaded        = lookup  SLIT("-fspecialise-overloaded")
 215 opt_SpecialiseTrace             = lookup  SLIT("-ftrace-specialisation")
 216 opt_SpecialiseUnboxed           = lookup  SLIT("-fspecialise-unboxed")
 217 opt_StgDoLetNoEscapes           = lookup  SLIT("-flet-no-escape")
 218 opt_Verbose                     = lookup  SLIT("-v")
 219 opt_SccGroup                    = lookup_str "-G="
 220 opt_ProduceC                    = lookup_str "-C="
 221 opt_ProduceS                    = lookup_str "-S="
 222 opt_ProduceHi                   = lookup_str "-hifile=" -- the one to produce this time
 223 opt_HiMap                       = lookup_str "-himap="  -- file saying where to look for .hi files
 224 opt_EnsureSplittableC           = lookup_str "-fglobalise-toplev-names="
 225 opt_UnfoldingUseThreshold       = lookup_int "-funfolding-use-threshold"
 226 opt_UnfoldingCreationThreshold  = lookup_int "-funfolding-creation-threshold"
 227 opt_UnfoldingOverrideThreshold  = lookup_int "-funfolding-override-threshold"
 228 opt_ReturnInRegsThreshold       = lookup_int "-freturn-in-regs-threshold"
 229
 230 opt_NoImplicitPrelude           = lookup  SLIT("-fno-implicit-prelude")
 231 opt_IgnoreIfacePragmas          = lookup  SLIT("-fignore-interface-pragmas")
 232 \end{code}
 233
 234 \begin{code}
 235 classifyOpts :: ([CoreToDo],    -- Core-to-Core processing spec
 236                  [StgToDo])     -- STG-to-STG   processing spec
 237
 238 classifyOpts = sep argv [] [] -- accumulators...
 239   where
 240     sep :: [FAST_STRING]                         -- cmd-line opts (input)
 241         -> [CoreToDo] -> [StgToDo]       -- to_do accumulators
 242         -> ([CoreToDo], [StgToDo])       -- result
 243
 244     sep [] core_td stg_td -- all done!
 245       = (reverse core_td, reverse stg_td)
 246
 247 #       define CORE_TD(to_do) sep opts (to_do:core_td) stg_td
 248 #       define STG_TD(to_do)  sep opts core_td (to_do:stg_td)
 249 #       define IGNORE_ARG()   sep opts core_td stg_td
 250
 251     sep (opt1:opts) core_td stg_td
 252       =
 253         case (_UNPK_ opt1) of -- the non-"just match a string" options are at the end...
 254
 255           ',' : _       -> IGNORE_ARG() -- it is for the parser
 256
 257           "-fsimplify"  -> -- gather up SimplifierSwitches specially...
 258                            simpl_sep opts [] core_td stg_td
 259
 260           "-fcalc-inlinings1"-> CORE_TD(CoreDoCalcInlinings1)
 261           "-fcalc-inlinings2"-> CORE_TD(CoreDoCalcInlinings2)
 262           "-ffloat-inwards"  -> CORE_TD(CoreDoFloatInwards)
 263           "-ffull-laziness"  -> CORE_TD(CoreDoFullLaziness)
 264           "-fliberate-case"  -> CORE_TD(CoreLiberateCase)
 265           "-fprint-core"     -> CORE_TD(CoreDoPrintCore)
 266           "-fstatic-args"    -> CORE_TD(CoreDoStaticArgs)
 267           "-fstrictness"     -> CORE_TD(CoreDoStrictness)
 268           "-fspecialise"     -> CORE_TD(CoreDoSpecialising)
 269           "-fdeforest"       -> CORE_TD(CoreDoDeforest)
 270           "-fadd-auto-sccs"  -> CORE_TD(CoreDoAutoCostCentres)
 271           "-ffoldr-build-worker-wrapper"  -> CORE_TD(CoreDoFoldrBuildWorkerWrapper)
 272           "-ffoldr-build-ww-anal"  -> CORE_TD(CoreDoFoldrBuildWWAnal)
 273
 274           "-fstg-static-args" -> STG_TD(StgDoStaticArgs)
 275           "-fupdate-analysis" -> STG_TD(StgDoUpdateAnalysis)
 276           "-dstg-stats"       -> STG_TD(D_stg_stats)
 277           "-flambda-lift"     -> STG_TD(StgDoLambdaLift)
 278           "-fmassage-stg-for-profiling" -> STG_TD(StgDoMassageForProfiling)
 279
 280           _ -> -- NB: the driver is really supposed to handle bad options
 281                IGNORE_ARG()
 282
 283     ----------------
 284
 285     simpl_sep :: [FAST_STRING]      -- cmd-line opts (input)
 286         -> [SimplifierSwitch]       -- simplifier-switch accumulator
 287         -> [CoreToDo] -> [StgToDo]  -- to_do accumulators
 288         -> ([CoreToDo], [StgToDo])  -- result
 289
 290         -- "simpl_sep" tailcalls "sep" once it's seen one set
 291         -- of SimplifierSwitches for a CoreDoSimplify.
 292
 293 #ifdef DEBUG
 294     simpl_sep input@[] simpl_sw core_td stg_td
 295       = panic "simpl_sep []"
 296 #endif
 297
 298         -- The SimplifierSwitches should be delimited by "(" and ")".
 299
 300     simpl_sep (opt1:opts) simpl_sw core_td stg_td
 301       = case (_UNPK_ opt1) of
 302           "(" -> ASSERT (null simpl_sw)
 303                  simpl_sep opts [] core_td stg_td
 304           ")" -> let
 305                     this_simpl = CoreDoSimplify (isAmongSimpl simpl_sw)
 306                  in
 307                  sep opts (this_simpl : core_td) stg_td
 308
 309 #         define SIMPL_SW(sw) simpl_sep opts (sw:simpl_sw) core_td stg_td
 310
 311           -- the non-"just match a string" options are at the end...
 312           "-fshow-simplifier-progress"      -> SIMPL_SW(ShowSimplifierProgress)
 313           "-fcode-duplication-ok"           -> SIMPL_SW(SimplOkToDupCode)
 314           "-ffloat-lets-exposing-whnf"      -> SIMPL_SW(SimplFloatLetsExposingWHNF)
 315           "-ffloat-primops-ok"              -> SIMPL_SW(SimplOkToFloatPrimOps)
 316           "-falways-float-lets-from-lets"   -> SIMPL_SW(SimplAlwaysFloatLetsFromLets)
 317           "-fdo-case-elim"                  -> SIMPL_SW(SimplDoCaseElim)
 318           "-fdo-eta-reduction"              -> SIMPL_SW(SimplDoEtaReduction)
 319           "-fdo-lambda-eta-expansion"       -> SIMPL_SW(SimplDoLambdaEtaExpansion)
 320           "-fdo-foldr-build"                -> SIMPL_SW(SimplDoFoldrBuild)
 321           "-fdo-not-fold-back-append"       -> SIMPL_SW(SimplDontFoldBackAppend)
 322           "-fdo-arity-expand"               -> SIMPL_SW(SimplDoArityExpand)
 323           "-fdo-inline-foldr-build"         -> SIMPL_SW(SimplDoInlineFoldrBuild)
 324           "-freuse-con"                     -> SIMPL_SW(SimplReuseCon)
 325           "-fcase-of-case"                  -> SIMPL_SW(SimplCaseOfCase)
 326           "-flet-to-case"                   -> SIMPL_SW(SimplLetToCase)
 327           "-fpedantic-bottoms"              -> SIMPL_SW(SimplPedanticBottoms)
 328           "-fkeep-spec-pragma-ids"          -> SIMPL_SW(KeepSpecPragmaIds)
 329           "-fkeep-unused-bindings"          -> SIMPL_SW(KeepUnusedBindings)
 330           "-fmay-delete-conjurable-ids"     -> SIMPL_SW(SimplMayDeleteConjurableIds)
 331           "-fessential-unfoldings-only"     -> SIMPL_SW(EssentialUnfoldingsOnly)
 332           "-fignore-inline-pragma"          -> SIMPL_SW(IgnoreINLINEPragma)
 333           "-fno-let-from-case"              -> SIMPL_SW(SimplNoLetFromCase)
 334           "-fno-let-from-app"               -> SIMPL_SW(SimplNoLetFromApp)
 335           "-fno-let-from-strict-let"        -> SIMPL_SW(SimplNoLetFromStrictLet)
 336
 337           o | starts_with_msi  -> SIMPL_SW(MaxSimplifierIterations (read after_msi))
 338             | starts_with_suut -> SIMPL_SW(SimplUnfoldingUseThreshold (read after_suut))
 339             | starts_with_suct -> SIMPL_SW(SimplUnfoldingCreationThreshold (read after_suct))
 340            where
 341             maybe_suut          = startsWith "-fsimpl-uf-use-threshold"      o
 342             maybe_suct          = startsWith "-fsimpl-uf-creation-threshold" o
 343             maybe_msi           = startsWith "-fmax-simplifier-iterations"   o
 344             starts_with_suut    = maybeToBool maybe_suut
 345             starts_with_suct    = maybeToBool maybe_suct
 346             starts_with_msi     = maybeToBool maybe_msi
 347             (Just after_suut)   = maybe_suut
 348             (Just after_suct)   = maybe_suct
 349             (Just after_msi)    = maybe_msi
 350
 351           _ -> -- NB: the driver is really supposed to handle bad options
 352                simpl_sep opts simpl_sw core_td stg_td
 353 \end{code}
 354
 355 %************************************************************************
 356 %*                                                                      *
 357 \subsection{Switch ordering}
 358 %*                                                                      *
 359 %************************************************************************
 360
 361 In spite of the @Produce*@ and @SccGroup@ constructors, these things
 362 behave just like enumeration types.
 363
 364 \begin{code}
 365 instance Eq SimplifierSwitch where
 366     a == b = tagOf_SimplSwitch a _EQ_ tagOf_SimplSwitch b
 367
 368 instance Ord SimplifierSwitch where
 369     a <  b  = tagOf_SimplSwitch a _LT_ tagOf_SimplSwitch b
 370     a <= b  = tagOf_SimplSwitch a _LE_ tagOf_SimplSwitch b
 371
 372 tagOf_SimplSwitch SimplOkToDupCode              =(ILIT(0) :: FAST_INT)
 373 tagOf_SimplSwitch SimplFloatLetsExposingWHNF    = ILIT(1)
 374 tagOf_SimplSwitch SimplOkToFloatPrimOps         = ILIT(2)
 375 tagOf_SimplSwitch SimplAlwaysFloatLetsFromLets  = ILIT(3)
 376 tagOf_SimplSwitch SimplDoCaseElim               = ILIT(4)
 377 tagOf_SimplSwitch SimplReuseCon                 = ILIT(5)
 378 tagOf_SimplSwitch SimplCaseOfCase               = ILIT(6)
 379 tagOf_SimplSwitch SimplLetToCase                = ILIT(7)
 380 tagOf_SimplSwitch SimplMayDeleteConjurableIds   = ILIT(9)
 381 tagOf_SimplSwitch SimplPedanticBottoms          = ILIT(10)
 382 tagOf_SimplSwitch SimplDoArityExpand            = ILIT(11)
 383 tagOf_SimplSwitch SimplDoFoldrBuild             = ILIT(12)
 384 tagOf_SimplSwitch SimplDoInlineFoldrBuild       = ILIT(14)
 385 tagOf_SimplSwitch IgnoreINLINEPragma            = ILIT(15)
 386 tagOf_SimplSwitch SimplDoLambdaEtaExpansion     = ILIT(16)
 387 tagOf_SimplSwitch SimplDoEtaReduction           = ILIT(18)
 388 tagOf_SimplSwitch EssentialUnfoldingsOnly       = ILIT(19)
 389 tagOf_SimplSwitch ShowSimplifierProgress        = ILIT(20)
 390 tagOf_SimplSwitch (MaxSimplifierIterations _)   = ILIT(21)
 391 tagOf_SimplSwitch (SimplUnfoldingUseThreshold _)      = ILIT(22)
 392 tagOf_SimplSwitch (SimplUnfoldingCreationThreshold _) = ILIT(23)
 393 tagOf_SimplSwitch KeepSpecPragmaIds             = ILIT(24)
 394 tagOf_SimplSwitch KeepUnusedBindings            = ILIT(25)
 395 tagOf_SimplSwitch SimplNoLetFromCase            = ILIT(26)
 396 tagOf_SimplSwitch SimplNoLetFromApp             = ILIT(27)
 397 tagOf_SimplSwitch SimplNoLetFromStrictLet       = ILIT(28)
 398 tagOf_SimplSwitch SimplDontFoldBackAppend       = ILIT(29)
 399 -- If you add anything here, be sure to change lAST_SIMPL_SWITCH_TAG, too!
 400
 401 tagOf_SimplSwitch _ = panic# "tagOf_SimplSwitch"
 402
 403 lAST_SIMPL_SWITCH_TAG = IBOX(tagOf_SimplSwitch SimplDontFoldBackAppend)
 404 \end{code}
 405
 406 %************************************************************************
 407 %*                                                                      *
 408 \subsection{Switch lookup}
 409 %*                                                                      *
 410 %************************************************************************
 411
 412 \begin{code}
 413 isAmongSimpl :: [SimplifierSwitch] -> SimplifierSwitch -> SwitchResult
 414
 415 isAmongSimpl on_switches
 416   = let
 417         tidied_on_switches = foldl rm_dups [] on_switches
 418
 419         sw_tbl :: Array Int SwitchResult
 420
 421         sw_tbl = (array (0, lAST_SIMPL_SWITCH_TAG) -- bounds...
 422                         all_undefined)
 423                  // defined_elems
 424
 425         all_undefined = [ i := SwBool False | i <- [0 .. lAST_SIMPL_SWITCH_TAG ] ]
 426
 427         defined_elems = map mk_assoc_elem tidied_on_switches
 428     in
 429     -- (avoid some unboxing, bounds checking, and other horrible things:)
 430     case sw_tbl of { _Array bounds_who_needs_'em stuff ->
 431     \ switch ->
 432         case (indexArray# stuff (tagOf_SimplSwitch switch)) of
 433           _Lift v -> v
 434     }
 435   where
 436     mk_assoc_elem k@(MaxSimplifierIterations lvl) = IBOX(tagOf_SimplSwitch k) := SwInt lvl
 437     mk_assoc_elem k@(SimplUnfoldingUseThreshold      i) = IBOX(tagOf_SimplSwitch k) := SwInt i
 438     mk_assoc_elem k@(SimplUnfoldingCreationThreshold i) = IBOX(tagOf_SimplSwitch k) := SwInt i
 439
 440     mk_assoc_elem k = IBOX(tagOf_SimplSwitch k) := SwBool   True -- I'm here, Mom!
 441
 442     -- cannot have duplicates if we are going to use the array thing
 443
 444     rm_dups switches_so_far switch
 445       = if switch `is_elem` switches_so_far
 446         then switches_so_far
 447         else switch : switches_so_far
 448       where
 449         sw `is_elem` []     = False
 450         sw `is_elem` (s:ss) = (tagOf_SimplSwitch sw) _EQ_ (tagOf_SimplSwitch s)
 451                             || sw `is_elem` ss
 452 \end{code}
 453
 454 %************************************************************************
 455 %*                                                                      *
 456 \subsection{Misc functions for command-line options}
 457 %*                                                                      *
 458 %************************************************************************
 459
 460
 461 \begin{code}
 462 switchIsOn :: (switch -> SwitchResult) -> switch -> Bool
 463
 464 switchIsOn lookup_fn switch
 465   = case (lookup_fn switch) of
 466       SwBool False -> False
 467       _            -> True
 468
 469 stringSwitchSet :: (switch -> SwitchResult)
 470                 -> (FAST_STRING -> switch)
 471                 -> Maybe FAST_STRING
 472
 473 stringSwitchSet lookup_fn switch
 474   = case (lookup_fn (switch (panic "stringSwitchSet"))) of
 475       SwString str -> Just str
 476       _            -> Nothing
 477
 478 intSwitchSet :: (switch -> SwitchResult)
 479              -> (Int -> switch)
 480              -> Maybe Int
 481
 482 intSwitchSet lookup_fn switch
 483   = case (lookup_fn (switch (panic "intSwitchSet"))) of
 484       SwInt int -> Just int
 485       _         -> Nothing
 486 \end{code}