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 (
  10         CoreToDo(..),
  11         SimplifierSwitch(..),
  12         StgToDo(..),
  13         SwitchResult(..),
  14         classifyOpts,
  15
  16         intSwitchSet,
  17         switchIsOn,
  18
  19         maybe_CompilingGhcInternals,
  20         opt_AllDemanded,
  21         opt_AllStrict,
  22         opt_AutoSccsOnAllToplevs,
  23         opt_AutoSccsOnExportedToplevs,
  24         opt_AutoSccsOnIndividualCafs,
  25         opt_CompilingGhcInternals,
  26         opt_D_dump_absC,
  27         opt_D_dump_asm,
  28         opt_D_dump_deforest,
  29         opt_D_dump_deriv,
  30         opt_D_dump_ds,
  31         opt_D_dump_flatC,
  32         opt_D_dump_occur_anal,
  33         opt_D_dump_rdr,
  34         opt_D_dump_realC,
  35         opt_D_dump_rn,
  36         opt_D_dump_simpl,
  37         opt_D_dump_simpl_iterations,
  38         opt_D_dump_spec,
  39         opt_D_dump_stg,
  40         opt_D_dump_stranal,
  41         opt_D_dump_tc,
  42         opt_D_show_passes,
  43         opt_D_show_rn_trace,
  44         opt_D_simplifier_stats,
  45         opt_D_source_stats,
  46         opt_D_verbose_core2core,
  47         opt_D_verbose_stg2stg,
  48         opt_DoCoreLinting,
  49         opt_DoStgLinting,
  50         opt_DoSemiTagging,
  51         opt_DoEtaReduction,
  52         opt_DoTickyProfiling,
  53         opt_EnsureSplittableC,
  54         opt_FoldrBuildOn,
  55         opt_FoldrBuildTrace,
  56         opt_ForConcurrent,
  57         opt_GlasgowExts,
  58         opt_GranMacros,
  59         opt_Haskell_1_3,
  60         opt_HiMap,
  61         opt_IgnoreIfacePragmas,
  62         opt_IgnoreStrictnessPragmas,
  63         opt_IrrefutableEverything,
  64         opt_IrrefutableTuples,
  65         opt_LiberateCaseThreshold,
  66         opt_NoImplicitPrelude,
  67         opt_NumbersStrict,
  68         opt_OmitBlackHoling,
  69         opt_OmitDefaultInstanceMethods,
  70         opt_OmitInterfacePragmas,
  71         opt_PprStyle_All,
  72         opt_PprStyle_Debug,
  73         opt_PprStyle_User,
  74         opt_ProduceC,
  75         opt_ProduceHi,
  76         opt_ProduceS,
  77         opt_ReportWhyUnfoldingsDisallowed,
  78         opt_ReturnInRegsThreshold,
  79         opt_SccGroup,
  80         opt_SccProfilingOn,
  81         opt_ShowImportSpecs,
  82         opt_ShowPragmaNameErrs,
  83         opt_SigsRequired,
  84         opt_SourceUnchanged,
  85         opt_SpecialiseAll,
  86         opt_SpecialiseImports,
  87         opt_SpecialiseOverloaded,
  88         opt_SpecialiseTrace,
  89         opt_SpecialiseUnboxed,
  90         opt_StgDoLetNoEscapes,
  91
  92         opt_InterfaceUnfoldThreshold,
  93         opt_UnfoldingCreationThreshold,
  94         opt_UnfoldingConDiscount,
  95         opt_UnfoldingUseThreshold,
  96
  97         opt_Verbose,
  98         opt_WarnNameShadowing,
  99         opt_WarnUnusedNames,
 100         opt_WarnIncompletePatterns,
 101         opt_TyConPruning
 102     ) where
 103
 104 IMPORT_1_3(Array(array, (//)))
 105 #if defined(__GLASGOW_HASKELL__) && __GLASGOW_HASKELL__ <= 201
 106 import PreludeGlaST     -- bad bad bad boy, Will (_Array internals)
 107 #else
 108 import GlaExts
 109 import ArrBase
 110 import PrelBase (Lift(..))
 111 #endif
 112 import Argv
 113
 114 CHK_Ubiq() -- debugging consistency check
 115
 116 import Constants        -- Default values for some flags
 117
 118 import Maybes           ( assocMaybe, firstJust, maybeToBool )
 119 import Util             ( startsWith, panic, panic#, assertPanic )
 120 \end{code}
 121
 122 A command-line {\em switch} is (generally) either on or off; e.g., the
 123 ``verbose'' (-v) switch is either on or off.  (The \tr{-G<group>}
 124 switch is an exception; it's set to a string, or nothing.)
 125
 126 A list of {\em ToDo}s is things to be done in a particular part of
 127 processing.  A (fictitious) example for the Core-to-Core simplifier
 128 might be: run the simplifier, then run the strictness analyser, then
 129 run the simplifier again (three ``todos'').
 130
 131 There are three ``to-do processing centers'' at the moment.  In the
 132 main loop (\tr{main/Main.lhs}), in the Core-to-Core processing loop
 133 (\tr{simplCore/SimplCore.lhs), and in the STG-to-STG processing loop
 134 (\tr{simplStg/SimplStg.lhs}).
 135
 136 %************************************************************************
 137 %*                                                                      *
 138 \subsection{Datatypes associated with command-line options}
 139 %*                                                                      *
 140 %************************************************************************
 141
 142 \begin{code}
 143 data SwitchResult
 144   = SwBool      Bool            -- on/off
 145   | SwString    FAST_STRING     -- nothing or a String
 146   | SwInt       Int             -- nothing or an Int
 147 \end{code}
 148
 149 \begin{code}
 150 data CoreToDo           -- These are diff core-to-core passes,
 151                         -- which may be invoked in any order,
 152                         -- as many times as you like.
 153
 154   = CoreDoSimplify      -- The core-to-core simplifier.
 155         (SimplifierSwitch -> SwitchResult)
 156                         -- Each run of the simplifier can take a different
 157                         -- set of simplifier-specific flags.
 158   | CoreDoCalcInlinings1
 159   | CoreDoCalcInlinings2
 160   | CoreDoFloatInwards
 161   | CoreDoFullLaziness
 162   | CoreLiberateCase
 163   | CoreDoPrintCore
 164   | CoreDoStaticArgs
 165   | CoreDoStrictness
 166   | CoreDoSpecialising
 167   | CoreDoDeforest
 168   | CoreDoFoldrBuildWorkerWrapper
 169   | CoreDoFoldrBuildWWAnal
 170 \end{code}
 171
 172 \begin{code}
 173 data StgToDo
 174   = StgDoStaticArgs
 175   | StgDoUpdateAnalysis
 176   | StgDoLambdaLift
 177   | StgDoMassageForProfiling  -- should be (next to) last
 178   -- There's also setStgVarInfo, but its absolute "lastness"
 179   -- is so critical that it is hardwired in (no flag).
 180   | D_stg_stats
 181 \end{code}
 182
 183 \begin{code}
 184 data SimplifierSwitch
 185   = SimplOkToDupCode
 186   | SimplFloatLetsExposingWHNF
 187   | SimplOkToFloatPrimOps
 188   | SimplAlwaysFloatLetsFromLets
 189   | SimplDoCaseElim
 190   | SimplReuseCon
 191   | SimplCaseOfCase
 192   | SimplLetToCase
 193   | SimplMayDeleteConjurableIds
 194   | SimplPedanticBottoms -- see Simplifier for an explanation
 195   | SimplDoArityExpand   -- expand arity of bindings
 196   | SimplDoFoldrBuild    -- This is the per-simplification flag;
 197                          -- see also FoldrBuildOn, used elsewhere
 198                          -- in the compiler.
 199   | SimplDoInlineFoldrBuild
 200                          -- inline foldr/build (*after* f/b rule is used)
 201
 202   | IgnoreINLINEPragma
 203   | SimplDoLambdaEtaExpansion
 204
 205   | EssentialUnfoldingsOnly -- never mind the thresholds, only
 206                             -- do unfoldings that *must* be done
 207                             -- (to saturate constructors and primitives)
 208
 209   | ShowSimplifierProgress  -- report counts on every interation
 210
 211   | MaxSimplifierIterations Int
 212
 213   | KeepSpecPragmaIds       -- We normally *toss* Ids we can do without
 214   | KeepUnusedBindings
 215
 216   | SimplNoLetFromCase      -- used when turning off floating entirely
 217   | SimplNoLetFromApp       -- (for experimentation only) WDP 95/10
 218   | SimplNoLetFromStrictLet
 219
 220   | SimplDontFoldBackAppend
 221                         -- we fold `foldr (:)' back into flip (++),
 222                         -- but we *don't* want to do it when compiling
 223                         -- List.hs, otherwise
 224                         -- xs ++ ys = foldr (:) ys xs
 225                         -- {- via our loopback -}
 226                         -- xs ++ ys = xs ++ ys
 227                         -- Oops!
 228                         -- So only use this flag inside List.hs
 229                         -- (Sigh, what a HACK, Andy.  WDP 96/01)
 230
 231   | SimplCaseMerge
 232   | SimplCaseScrutinee  -- This flag tells that the expression being simplified is
 233                         -- the scrutinee of a case expression, so we should
 234                         -- apply the scrutinee discount when considering inlinings.
 235                         -- See SimplVar.lhs
 236 \end{code}
 237
 238 %************************************************************************
 239 %*                                                                      *
 240 \subsection{Classifying command-line options}
 241 %*                                                                      *
 242 %************************************************************************
 243
 244 \begin{code}
 245 lookUp         :: FAST_STRING -> Bool
 246 lookup_int     :: String -> Maybe Int
 247 lookup_def_int :: String -> Int -> Int
 248 lookup_str     :: String -> Maybe String
 249
 250 lookUp     sw = maybeToBool (assoc_opts sw)
 251
 252 lookup_str sw = firstJust (map (startsWith sw) unpacked_opts)
 253
 254 lookup_int sw = case (lookup_str sw) of
 255                   Nothing -> Nothing
 256                   Just xx -> Just (read xx)
 257
 258 lookup_def_int sw def = case (lookup_str sw) of
 259                             Nothing -> def              -- Use default
 260                             Just xx -> read xx
 261
 262 assoc_opts    = assocMaybe [ (a, True) | a <- argv ]
 263 unpacked_opts = map _UNPK_ argv
 264 \end{code}
 265
 266 \begin{code}
 267 opt_AllDemanded                 = lookUp  SLIT("-fall-demanded")
 268 opt_AllStrict                   = lookUp  SLIT("-fall-strict")
 269 opt_AutoSccsOnAllToplevs        = lookUp  SLIT("-fauto-sccs-on-all-toplevs")
 270 opt_AutoSccsOnExportedToplevs   = lookUp  SLIT("-fauto-sccs-on-exported-toplevs")
 271 opt_AutoSccsOnIndividualCafs    = lookUp  SLIT("-fauto-sccs-on-individual-cafs")
 272 opt_CompilingGhcInternals       = maybeToBool maybe_CompilingGhcInternals
 273 maybe_CompilingGhcInternals     = lookup_str "-fcompiling-ghc-internals="
 274 opt_D_dump_absC                 = lookUp  SLIT("-ddump-absC")
 275 opt_D_dump_asm                  = lookUp  SLIT("-ddump-asm")
 276 opt_D_dump_deforest             = lookUp  SLIT("-ddump-deforest")
 277 opt_D_dump_deriv                = lookUp  SLIT("-ddump-deriv")
 278 opt_D_dump_ds                   = lookUp  SLIT("-ddump-ds")
 279 opt_D_dump_flatC                = lookUp  SLIT("-ddump-flatC")
 280 opt_D_dump_occur_anal           = lookUp  SLIT("-ddump-occur-anal")
 281 opt_D_dump_rdr                  = lookUp  SLIT("-ddump-rdr")
 282 opt_D_dump_realC                = lookUp  SLIT("-ddump-realC")
 283 opt_D_dump_rn                   = lookUp  SLIT("-ddump-rn")
 284 opt_D_dump_simpl                = lookUp  SLIT("-ddump-simpl")
 285 opt_D_dump_simpl_iterations     = lookUp  SLIT("-ddump-simpl-iterations")
 286 opt_D_dump_spec                 = lookUp  SLIT("-ddump-spec")
 287 opt_D_dump_stg                  = lookUp  SLIT("-ddump-stg")
 288 opt_D_dump_stranal              = lookUp  SLIT("-ddump-stranal")
 289 opt_D_dump_tc                   = lookUp  SLIT("-ddump-tc")
 290 opt_D_show_passes               = lookUp  SLIT("-dshow-passes")
 291 opt_D_show_rn_trace             = lookUp  SLIT("-dshow-rn-trace")
 292 opt_D_simplifier_stats          = lookUp  SLIT("-dsimplifier-stats")
 293 opt_D_source_stats              = lookUp  SLIT("-dsource-stats")
 294 opt_D_verbose_core2core         = lookUp  SLIT("-dverbose-simpl")
 295 opt_D_verbose_stg2stg           = lookUp  SLIT("-dverbose-stg")
 296 opt_DoCoreLinting               = lookUp  SLIT("-dcore-lint")
 297 opt_DoStgLinting                = lookUp  SLIT("-dstg-lint")
 298 opt_DoSemiTagging               = lookUp  SLIT("-fsemi-tagging")
 299 opt_DoTickyProfiling            = lookUp  SLIT("-fticky-ticky")
 300 opt_DoEtaReduction              = lookUp  SLIT("-fdo-eta-reduction")
 301 opt_EnsureSplittableC           = lookUp  SLIT("-fglobalise-toplev-names")
 302 opt_FoldrBuildOn                = lookUp  SLIT("-ffoldr-build-on")
 303 opt_FoldrBuildTrace             = lookUp  SLIT("-ffoldr-build-trace")
 304 opt_ForConcurrent               = lookUp  SLIT("-fconcurrent")
 305 opt_GranMacros                  = lookUp  SLIT("-fgransim")
 306 opt_GlasgowExts                 = lookUp  SLIT("-fglasgow-exts")
 307 opt_Haskell_1_3                 = lookUp  SLIT("-fhaskell-1.3")
 308 opt_HiMap                       = lookup_str "-himap="  -- file saying where to look for .hi files
 309 opt_IgnoreIfacePragmas          = lookUp  SLIT("-fignore-interface-pragmas")
 310 opt_IgnoreStrictnessPragmas     = lookUp  SLIT("-fignore-strictness-pragmas")
 311 opt_IrrefutableEverything       = lookUp  SLIT("-firrefutable-everything")
 312 opt_IrrefutableTuples           = lookUp  SLIT("-firrefutable-tuples")
 313 opt_NoImplicitPrelude           = lookUp  SLIT("-fno-implicit-prelude")
 314 opt_NumbersStrict               = lookUp  SLIT("-fnumbers-strict")
 315 opt_OmitBlackHoling             = lookUp  SLIT("-dno-black-holing")
 316 opt_OmitDefaultInstanceMethods  = lookUp  SLIT("-fomit-default-instance-methods")
 317 opt_OmitInterfacePragmas        = lookUp  SLIT("-fomit-interface-pragmas")
 318 opt_PprStyle_All                = lookUp  SLIT("-dppr-all")
 319 opt_PprStyle_Debug              = lookUp  SLIT("-dppr-debug")
 320 opt_PprStyle_User               = lookUp  SLIT("-dppr-user")
 321 opt_ProduceC                    = lookup_str "-C="
 322 opt_ProduceS                    = lookup_str "-S="
 323 opt_ProduceHi                   = lookup_str "-hifile=" -- the one to produce this time
 324 opt_ReportWhyUnfoldingsDisallowed= lookUp SLIT("-freport-disallowed-unfoldings")
 325 opt_SccProfilingOn              = lookUp  SLIT("-fscc-profiling")
 326 opt_ShowImportSpecs             = lookUp  SLIT("-fshow-import-specs")
 327 opt_ShowPragmaNameErrs          = lookUp  SLIT("-fshow-pragma-name-errs")
 328 opt_SigsRequired                = lookUp  SLIT("-fsignatures-required")
 329 opt_SourceUnchanged             = lookUp  SLIT("-fsource-unchanged")
 330 opt_SpecialiseAll               = lookUp  SLIT("-fspecialise-all")
 331 opt_SpecialiseImports           = lookUp  SLIT("-fspecialise-imports")
 332 opt_SpecialiseOverloaded        = lookUp  SLIT("-fspecialise-overloaded")
 333 opt_SpecialiseTrace             = lookUp  SLIT("-ftrace-specialisation")
 334 opt_SpecialiseUnboxed           = lookUp  SLIT("-fspecialise-unboxed")
 335 opt_StgDoLetNoEscapes           = lookUp  SLIT("-flet-no-escape")
 336 opt_ReturnInRegsThreshold       = lookup_int "-freturn-in-regs-threshold"
 337 opt_SccGroup                    = lookup_str "-G="
 338 opt_Verbose                     = lookUp  SLIT("-v")
 339
 340 opt_InterfaceUnfoldThreshold    = lookup_def_int "-funfolding-interface-threshold" iNTERFACE_UNFOLD_THRESHOLD
 341 opt_UnfoldingCreationThreshold  = lookup_def_int "-funfolding-creation-threshold"  uNFOLDING_CREATION_THRESHOLD
 342 opt_UnfoldingUseThreshold       = lookup_def_int "-funfolding-use-threshold"       uNFOLDING_USE_THRESHOLD
 343 opt_UnfoldingConDiscount        = lookup_def_int "-funfolding-con-discount"        uNFOLDING_CON_DISCOUNT_WEIGHT
 344
 345 opt_LiberateCaseThreshold       = lookup_def_int "-fliberate-case-threshold"       lIBERATE_CASE_THRESHOLD
 346 opt_WarnNameShadowing           = lookUp  SLIT("-fwarn-name-shadowing")
 347 opt_WarnIncompletePatterns      = not (lookUp  SLIT("-fno-warn-incomplete-patterns"))
 348 opt_WarnUnusedNames             = lookUp  SLIT("-fwarn-unused-names")
 349 opt_TyConPruning                = not (lookUp SLIT("-fno-tycon-pruning"))
 350
 351 -- opt_UnfoldingUseThreshold    = lookup_int "-funfolding-use-threshold"
 352 -- opt_UnfoldingOverrideThreshold       = lookup_int "-funfolding-override-threshold"
 353 \end{code}
 354
 355 \begin{code}
 356 classifyOpts :: ([CoreToDo],    -- Core-to-Core processing spec
 357                  [StgToDo])     -- STG-to-STG   processing spec
 358
 359 classifyOpts = sep argv [] [] -- accumulators...
 360   where
 361     sep :: [FAST_STRING]                         -- cmd-line opts (input)
 362         -> [CoreToDo] -> [StgToDo]       -- to_do accumulators
 363         -> ([CoreToDo], [StgToDo])       -- result
 364
 365     sep [] core_td stg_td -- all done!
 366       = (reverse core_td, reverse stg_td)
 367
 368 #       define CORE_TD(to_do) sep opts (to_do:core_td) stg_td
 369 #       define STG_TD(to_do)  sep opts core_td (to_do:stg_td)
 370 #       define IGNORE_ARG()   sep opts core_td stg_td
 371
 372     sep (opt1:opts) core_td stg_td
 373       =
 374         case (_UNPK_ opt1) of -- the non-"just match a string" options are at the end...
 375
 376           ',' : _       -> IGNORE_ARG() -- it is for the parser
 377
 378           "-fsimplify"  -> -- gather up SimplifierSwitches specially...
 379                            simpl_sep opts defaultSimplSwitches core_td stg_td
 380
 381           "-fcalc-inlinings1"-> CORE_TD(CoreDoCalcInlinings1)
 382           "-fcalc-inlinings2"-> CORE_TD(CoreDoCalcInlinings2)
 383           "-ffloat-inwards"  -> CORE_TD(CoreDoFloatInwards)
 384           "-ffull-laziness"  -> CORE_TD(CoreDoFullLaziness)
 385           "-fliberate-case"  -> CORE_TD(CoreLiberateCase)
 386           "-fprint-core"     -> CORE_TD(CoreDoPrintCore)
 387           "-fstatic-args"    -> CORE_TD(CoreDoStaticArgs)
 388           "-fstrictness"     -> CORE_TD(CoreDoStrictness)
 389           "-fspecialise"     -> CORE_TD(CoreDoSpecialising)
 390           "-fdeforest"       -> CORE_TD(CoreDoDeforest)
 391           "-ffoldr-build-worker-wrapper"  -> CORE_TD(CoreDoFoldrBuildWorkerWrapper)
 392           "-ffoldr-build-ww-anal"  -> CORE_TD(CoreDoFoldrBuildWWAnal)
 393
 394           "-fstg-static-args" -> STG_TD(StgDoStaticArgs)
 395           "-fupdate-analysis" -> STG_TD(StgDoUpdateAnalysis)
 396           "-dstg-stats"       -> STG_TD(D_stg_stats)
 397           "-flambda-lift"     -> STG_TD(StgDoLambdaLift)
 398           "-fmassage-stg-for-profiling" -> STG_TD(StgDoMassageForProfiling)
 399
 400           _ -> -- NB: the driver is really supposed to handle bad options
 401                IGNORE_ARG()
 402
 403     ----------------
 404
 405     simpl_sep :: [FAST_STRING]      -- cmd-line opts (input)
 406         -> [SimplifierSwitch]       -- simplifier-switch accumulator
 407         -> [CoreToDo] -> [StgToDo]  -- to_do accumulators
 408         -> ([CoreToDo], [StgToDo])  -- result
 409
 410         -- "simpl_sep" tailcalls "sep" once it's seen one set
 411         -- of SimplifierSwitches for a CoreDoSimplify.
 412
 413 #ifdef DEBUG
 414     simpl_sep input@[] simpl_sw core_td stg_td
 415       = panic "simpl_sep []"
 416 #endif
 417
 418         -- The SimplifierSwitches should be delimited by "(" and ")".
 419
 420     simpl_sep (opt1:opts) simpl_sw core_td stg_td
 421       = case (_UNPK_ opt1) of
 422           "(" -> simpl_sep opts simpl_sw core_td stg_td
 423           ")" -> let
 424                     this_simpl = CoreDoSimplify (isAmongSimpl simpl_sw)
 425                  in
 426                  sep opts (this_simpl : core_td) stg_td
 427
 428 #         define SIMPL_SW(sw) simpl_sep opts (sw:simpl_sw) core_td stg_td
 429
 430           -- the non-"just match a string" options are at the end...
 431           "-fshow-simplifier-progress"      -> SIMPL_SW(ShowSimplifierProgress)
 432           "-fcode-duplication-ok"           -> SIMPL_SW(SimplOkToDupCode)
 433           "-ffloat-lets-exposing-whnf"      -> SIMPL_SW(SimplFloatLetsExposingWHNF)
 434           "-ffloat-primops-ok"              -> SIMPL_SW(SimplOkToFloatPrimOps)
 435           "-falways-float-lets-from-lets"   -> SIMPL_SW(SimplAlwaysFloatLetsFromLets)
 436           "-fdo-case-elim"                  -> SIMPL_SW(SimplDoCaseElim)
 437           "-fdo-lambda-eta-expansion"       -> SIMPL_SW(SimplDoLambdaEtaExpansion)
 438           "-fdo-foldr-build"                -> SIMPL_SW(SimplDoFoldrBuild)
 439           "-fdo-not-fold-back-append"       -> SIMPL_SW(SimplDontFoldBackAppend)
 440           "-fdo-arity-expand"               -> SIMPL_SW(SimplDoArityExpand)
 441           "-fdo-inline-foldr-build"         -> SIMPL_SW(SimplDoInlineFoldrBuild)
 442           "-freuse-con"                     -> SIMPL_SW(SimplReuseCon)
 443           "-fcase-of-case"                  -> SIMPL_SW(SimplCaseOfCase)
 444           "-fcase-merge"                    -> SIMPL_SW(SimplCaseMerge)
 445           "-flet-to-case"                   -> SIMPL_SW(SimplLetToCase)
 446           "-fpedantic-bottoms"              -> SIMPL_SW(SimplPedanticBottoms)
 447           "-fkeep-spec-pragma-ids"          -> SIMPL_SW(KeepSpecPragmaIds)
 448           "-fkeep-unused-bindings"          -> SIMPL_SW(KeepUnusedBindings)
 449           "-fmay-delete-conjurable-ids"     -> SIMPL_SW(SimplMayDeleteConjurableIds)
 450           "-fessential-unfoldings-only"     -> SIMPL_SW(EssentialUnfoldingsOnly)
 451           "-fignore-inline-pragma"          -> SIMPL_SW(IgnoreINLINEPragma)
 452           "-fno-let-from-case"              -> SIMPL_SW(SimplNoLetFromCase)
 453           "-fno-let-from-app"               -> SIMPL_SW(SimplNoLetFromApp)
 454           "-fno-let-from-strict-let"        -> SIMPL_SW(SimplNoLetFromStrictLet)
 455
 456           o | starts_with_msi  -> SIMPL_SW(MaxSimplifierIterations (read after_msi))
 457            where
 458             maybe_msi           = startsWith "-fmax-simplifier-iterations"   o
 459             starts_with_msi     = maybeToBool maybe_msi
 460             (Just after_msi)    = maybe_msi
 461
 462           _ -> -- NB: the driver is really supposed to handle bad options
 463                simpl_sep opts simpl_sw core_td stg_td
 464 \end{code}
 465
 466 %************************************************************************
 467 %*                                                                      *
 468 \subsection{Switch ordering}
 469 %*                                                                      *
 470 %************************************************************************
 471
 472 In spite of the @Produce*@ and @SccGroup@ constructors, these things
 473 behave just like enumeration types.
 474
 475 \begin{code}
 476 instance Eq SimplifierSwitch where
 477     a == b = tagOf_SimplSwitch a _EQ_ tagOf_SimplSwitch b
 478
 479 instance Ord SimplifierSwitch where
 480     a <  b  = tagOf_SimplSwitch a _LT_ tagOf_SimplSwitch b
 481     a <= b  = tagOf_SimplSwitch a _LE_ tagOf_SimplSwitch b
 482
 483 tagOf_SimplSwitch SimplOkToDupCode              =(ILIT(0) :: FAST_INT)
 484 tagOf_SimplSwitch SimplFloatLetsExposingWHNF    = ILIT(1)
 485 tagOf_SimplSwitch SimplOkToFloatPrimOps         = ILIT(2)
 486 tagOf_SimplSwitch SimplAlwaysFloatLetsFromLets  = ILIT(3)
 487 tagOf_SimplSwitch SimplDoCaseElim               = ILIT(4)
 488 tagOf_SimplSwitch SimplReuseCon                 = ILIT(5)
 489 tagOf_SimplSwitch SimplCaseOfCase               = ILIT(6)
 490 tagOf_SimplSwitch SimplLetToCase                = ILIT(7)
 491 tagOf_SimplSwitch SimplMayDeleteConjurableIds   = ILIT(9)
 492 tagOf_SimplSwitch SimplPedanticBottoms          = ILIT(10)
 493 tagOf_SimplSwitch SimplDoArityExpand            = ILIT(11)
 494 tagOf_SimplSwitch SimplDoFoldrBuild             = ILIT(12)
 495 tagOf_SimplSwitch SimplDoInlineFoldrBuild       = ILIT(14)
 496 tagOf_SimplSwitch IgnoreINLINEPragma            = ILIT(15)
 497 tagOf_SimplSwitch SimplDoLambdaEtaExpansion     = ILIT(16)
 498 tagOf_SimplSwitch EssentialUnfoldingsOnly       = ILIT(19)
 499 tagOf_SimplSwitch ShowSimplifierProgress        = ILIT(20)
 500 tagOf_SimplSwitch (MaxSimplifierIterations _)   = ILIT(21)
 501 tagOf_SimplSwitch KeepSpecPragmaIds             = ILIT(25)
 502 tagOf_SimplSwitch KeepUnusedBindings            = ILIT(26)
 503 tagOf_SimplSwitch SimplNoLetFromCase            = ILIT(27)
 504 tagOf_SimplSwitch SimplNoLetFromApp             = ILIT(28)
 505 tagOf_SimplSwitch SimplNoLetFromStrictLet       = ILIT(29)
 506 tagOf_SimplSwitch SimplDontFoldBackAppend       = ILIT(30)
 507 tagOf_SimplSwitch SimplCaseMerge                = ILIT(31)
 508 tagOf_SimplSwitch SimplCaseScrutinee            = ILIT(32)
 509
 510 -- If you add anything here, be sure to change lAST_SIMPL_SWITCH_TAG, too!
 511
 512 tagOf_SimplSwitch _ = panic# "tagOf_SimplSwitch"
 513
 514 lAST_SIMPL_SWITCH_TAG = IBOX(tagOf_SimplSwitch SimplCaseScrutinee)
 515 \end{code}
 516
 517 %************************************************************************
 518 %*                                                                      *
 519 \subsection{Switch lookup}
 520 %*                                                                      *
 521 %************************************************************************
 522
 523 \begin{code}
 524 #if __GLASGOW_HASKELL__ == 201
 525 # define ARRAY      Array
 526 # define LIFT       GHCbase.Lift
 527 # define SET_TO     =:
 528 (=:) a b = (a,b)
 529 #elif __GLASGOW_HASKELL__ >= 202
 530 # define ARRAY      Array
 531 # define LIFT       Lift
 532 # define SET_TO     =:
 533 (=:) a b = (a,b)
 534 #else
 535 # define ARRAY      _Array
 536 # define LIFT       _Lift
 537 # define SET_TO     :=
 538 #endif
 539
 540 isAmongSimpl :: [SimplifierSwitch] -> SimplifierSwitch -> SwitchResult
 541
 542 isAmongSimpl on_switches                -- Switches mentioned later occur *earlier*
 543                                         -- in the list; defaults right at the end.
 544   = let
 545         tidied_on_switches = foldl rm_dups [] on_switches
 546                 -- The fold*l* ensures that we keep the latest switches;
 547                 -- ie the ones that occur earliest in the list.
 548
 549         sw_tbl :: Array Int SwitchResult
 550
 551         sw_tbl = (array (0, lAST_SIMPL_SWITCH_TAG) -- bounds...
 552                         all_undefined)
 553                  // defined_elems
 554
 555         all_undefined = [ i SET_TO SwBool False | i <- [0 .. lAST_SIMPL_SWITCH_TAG ] ]
 556
 557         defined_elems = map mk_assoc_elem tidied_on_switches
 558     in
 559     -- (avoid some unboxing, bounds checking, and other horrible things:)
 560     case sw_tbl of { ARRAY bounds_who_needs_'em stuff ->
 561     \ switch ->
 562         case (indexArray# stuff (tagOf_SimplSwitch switch)) of
 563           LIFT v -> v
 564     }
 565   where
 566     mk_assoc_elem k@(MaxSimplifierIterations lvl)       = IBOX(tagOf_SimplSwitch k) SET_TO SwInt lvl
 567
 568     mk_assoc_elem k = IBOX(tagOf_SimplSwitch k) SET_TO SwBool   True -- I'm here, Mom!
 569
 570     -- cannot have duplicates if we are going to use the array thing
 571     rm_dups switches_so_far switch
 572       = if switch `is_elem` switches_so_far
 573         then switches_so_far
 574         else switch : switches_so_far
 575       where
 576         sw `is_elem` []     = False
 577         sw `is_elem` (s:ss) = (tagOf_SimplSwitch sw) _EQ_ (tagOf_SimplSwitch s)
 578                             || sw `is_elem` ss
 579 \end{code}
 580
 581 Default settings for simplifier switches
 582
 583 \begin{code}
 584 defaultSimplSwitches = [MaxSimplifierIterations         1
 585                        ]
 586 \end{code}
 587
 588 %************************************************************************
 589 %*                                                                      *
 590 \subsection{Misc functions for command-line options}
 591 %*                                                                      *
 592 %************************************************************************
 593
 594
 595 \begin{code}
 596 switchIsOn :: (switch -> SwitchResult) -> switch -> Bool
 597
 598 switchIsOn lookup_fn switch
 599   = case (lookup_fn switch) of
 600       SwBool False -> False
 601       _            -> True
 602
 603 stringSwitchSet :: (switch -> SwitchResult)
 604                 -> (FAST_STRING -> switch)
 605                 -> Maybe FAST_STRING
 606
 607 stringSwitchSet lookup_fn switch
 608   = case (lookup_fn (switch (panic "stringSwitchSet"))) of
 609       SwString str -> Just str
 610       _            -> Nothing
 611
 612 intSwitchSet :: (switch -> SwitchResult)
 613              -> (Int -> switch)
 614              -> Maybe Int
 615
 616 intSwitchSet lookup_fn switch
 617   = case (lookup_fn (switch (panic "intSwitchSet"))) of
 618       SwInt int -> Just int
 619       _         -> Nothing
 620 \end{code}