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 module CmdLineOpts (
   8         CoreToDo(..),
   9         SimplifierSwitch(..),
  10         StgToDo(..),
  11         SwitchResult(..),
  12         classifyOpts,
  13
  14         intSwitchSet,
  15         switchIsOn,
  16
  17         maybe_CompilingGhcInternals,
  18         opt_AllStrict,
  19         opt_AllowOverlappingInstances,
  20         opt_AutoSccsOnAllToplevs,
  21         opt_AutoSccsOnExportedToplevs,
  22         opt_AutoSccsOnIndividualCafs,
  23         opt_CompilingGhcInternals,
  24         opt_D_dump_absC,
  25         opt_D_dump_asm,
  26         opt_D_dump_deriv,
  27         opt_D_dump_ds,
  28         opt_D_dump_flatC,
  29         opt_D_dump_occur_anal,
  30         opt_D_dump_rdr,
  31         opt_D_dump_realC,
  32         opt_D_dump_rn,
  33         opt_D_dump_simpl,
  34         opt_D_dump_simpl_iterations,
  35         opt_D_dump_spec,
  36         opt_D_dump_stg,
  37         opt_D_dump_stranal,
  38         opt_D_dump_tc,
  39         opt_D_show_passes,
  40         opt_D_show_rn_trace,
  41         opt_D_show_rn_imports,
  42         opt_D_simplifier_stats,
  43         opt_D_source_stats,
  44         opt_D_verbose_core2core,
  45         opt_D_verbose_stg2stg,
  46         opt_DoCoreLinting,
  47         opt_DoStgLinting,
  48         opt_DoSemiTagging,
  49         opt_DoEtaReduction,
  50         opt_DoTickyProfiling,
  51         opt_EnsureSplittableC,
  52         opt_FoldrBuildOn,
  53         opt_ForConcurrent,
  54         opt_GlasgowExts,
  55         opt_GranMacros,
  56         opt_HiMap,
  57         opt_IgnoreIfacePragmas,
  58         opt_IrrefutableTuples,
  59         opt_LiberateCaseThreshold,
  60         opt_MultiParamClasses,
  61         opt_NoHiCheck,
  62         opt_NoImplicitPrelude,
  63         opt_NumbersStrict,
  64         opt_OmitBlackHoling,
  65         opt_OmitInterfacePragmas,
  66         opt_PprStyle_All,
  67         opt_PprStyle_Debug,
  68         opt_PprStyle_User,              -- ToDo: rm
  69         opt_PprUserLength,
  70         opt_ProduceC,
  71         opt_ProduceHi,
  72         opt_ProduceS,
  73         opt_ReportWhyUnfoldingsDisallowed,
  74         opt_ReturnInRegsThreshold,
  75         opt_SccGroup,
  76         opt_SccProfilingOn,
  77         opt_ShowImportSpecs,
  78         opt_SigsRequired,
  79         opt_SourceUnchanged,
  80         opt_SpecialiseAll,
  81         opt_SpecialiseImports,
  82         opt_SpecialiseOverloaded,
  83         opt_SpecialiseTrace,
  84         opt_SpecialiseUnboxed,
  85         opt_StgDoLetNoEscapes,
  86
  87         opt_InterfaceUnfoldThreshold,
  88         opt_UnfoldingCreationThreshold,
  89         opt_UnfoldingConDiscount,
  90         opt_UnfoldingUseThreshold,
  91         opt_UnfoldingKeenessFactor,
  92
  93         opt_Verbose,
  94         opt_WarnNameShadowing,
  95         opt_WarnUnusedMatches,
  96         opt_WarnUnusedBinds,
  97         opt_WarnUnusedImports,
  98         opt_WarnIncompletePatterns,
  99         opt_WarnOverlappingPatterns,
 100         opt_WarnSimplePatterns,
 101         opt_WarnMissingMethods,
 102         opt_WarnDuplicateExports,
 103         opt_WarnHiShadows,
 104         opt_PruneTyDecls, opt_PruneInstDecls,
 105         opt_D_show_rn_stats
 106     ) where
 107
 108 #include "HsVersions.h"
 109
 110 import Array    ( array, (//) )
 111 import GlaExts
 112 import Argv
 113 import Constants        -- Default values for some flags
 114
 115 import Maybes           ( assocMaybe, firstJust, maybeToBool )
 116 import Util             ( startsWith, panic, panic# )
 117
 118 #if __GLASGOW_HASKELL__ < 301
 119 import ArrBase  ( Array(..) )
 120 #else
 121 import PrelArr  ( Array(..) )
 122 #endif
 123 \end{code}
 124
 125 A command-line {\em switch} is (generally) either on or off; e.g., the
 126 ``verbose'' (-v) switch is either on or off.  (The \tr{-G<group>}
 127 switch is an exception; it's set to a string, or nothing.)
 128
 129 A list of {\em ToDo}s is things to be done in a particular part of
 130 processing.  A (fictitious) example for the Core-to-Core simplifier
 131 might be: run the simplifier, then run the strictness analyser, then
 132 run the simplifier again (three ``todos'').
 133
 134 There are three ``to-do processing centers'' at the moment.  In the
 135 main loop (\tr{main/Main.lhs}), in the Core-to-Core processing loop
 136 (\tr{simplCore/SimplCore.lhs), and in the STG-to-STG processing loop
 137 (\tr{simplStg/SimplStg.lhs}).
 138
 139 %************************************************************************
 140 %*                                                                      *
 141 \subsection{Datatypes associated with command-line options}
 142 %*                                                                      *
 143 %************************************************************************
 144
 145 \begin{code}
 146 data SwitchResult
 147   = SwBool      Bool            -- on/off
 148   | SwString    FAST_STRING     -- nothing or a String
 149   | SwInt       Int             -- nothing or an Int
 150 \end{code}
 151
 152 \begin{code}
 153 data CoreToDo           -- These are diff core-to-core passes,
 154                         -- which may be invoked in any order,
 155                         -- as many times as you like.
 156
 157   = CoreDoSimplify      -- The core-to-core simplifier.
 158         (SimplifierSwitch -> SwitchResult)
 159                         -- Each run of the simplifier can take a different
 160                         -- set of simplifier-specific flags.
 161   | CoreDoCalcInlinings1
 162   | CoreDoCalcInlinings2
 163   | CoreDoFloatInwards
 164   | CoreDoFullLaziness
 165   | CoreLiberateCase
 166   | CoreDoPrintCore
 167   | CoreDoStaticArgs
 168   | CoreDoStrictness
 169   | CoreDoSpecialising
 170   | CoreDoFoldrBuildWorkerWrapper
 171   | CoreDoFoldrBuildWWAnal
 172 \end{code}
 173
 174 \begin{code}
 175 data StgToDo
 176   = StgDoStaticArgs
 177   | StgDoUpdateAnalysis
 178   | StgDoLambdaLift
 179   | StgDoMassageForProfiling  -- should be (next to) last
 180   -- There's also setStgVarInfo, but its absolute "lastness"
 181   -- is so critical that it is hardwired in (no flag).
 182   | D_stg_stats
 183 \end{code}
 184
 185 \begin{code}
 186 data SimplifierSwitch
 187   = SimplOkToDupCode
 188   | SimplFloatLetsExposingWHNF
 189   | SimplOkToFloatPrimOps
 190   | SimplAlwaysFloatLetsFromLets
 191   | SimplDoCaseElim
 192   | SimplReuseCon
 193   | SimplCaseOfCase
 194   | SimplLetToCase
 195   | SimplMayDeleteConjurableIds
 196   | SimplPedanticBottoms -- see Simplifier for an explanation
 197   | SimplDoArityExpand   -- expand arity of bindings
 198   | SimplDoFoldrBuild    -- This is the per-simplification flag;
 199                          -- see also FoldrBuildOn, used elsewhere
 200                          -- in the compiler.
 201   | SimplDoInlineFoldrBuild
 202                          -- inline foldr/build (*after* f/b rule is used)
 203
 204   | IgnoreINLINEPragma
 205   | SimplDoLambdaEtaExpansion
 206
 207   | EssentialUnfoldingsOnly -- never mind the thresholds, only
 208                             -- do unfoldings that *must* be done
 209                             -- (to saturate constructors and primitives)
 210
 211   | ShowSimplifierProgress  -- report counts on every interation
 212
 213   | MaxSimplifierIterations Int
 214
 215   | SimplNoLetFromCase      -- used when turning off floating entirely
 216   | SimplNoLetFromApp       -- (for experimentation only) WDP 95/10
 217   | SimplNoLetFromStrictLet
 218
 219   | SimplDontFoldBackAppend
 220                         -- we fold `foldr (:)' back into flip (++),
 221                         -- but we *don't* want to do it when compiling
 222                         -- List.hs, otherwise
 223                         -- xs ++ ys = foldr (:) ys xs
 224                         -- {- via our loopback -}
 225                         -- xs ++ ys = xs ++ ys
 226                         -- Oops!
 227                         -- So only use this flag inside List.hs
 228                         -- (Sigh, what a HACK, Andy.  WDP 96/01)
 229
 230   | SimplCaseMerge
 231   | SimplCaseScrutinee  -- This flag tells that the expression being simplified is
 232                         -- the scrutinee of a case expression, so we should
 233                         -- apply the scrutinee discount when considering inlinings.
 234                         -- See SimplVar.lhs
 235
 236   | SimplCloneBinds     -- This flag controls whether the simplifier should
 237                         -- always clone binder ids when creating expression
 238                         -- copies. The default is NO, but it needs to be turned on
 239                         -- prior to floating binders outwards.
 240                         -- (see comment inside SimplVar.simplBinder)
 241 \end{code}
 242
 243 %************************************************************************
 244 %*                                                                      *
 245 \subsection{Classifying command-line options}
 246 %*                                                                      *
 247 %************************************************************************
 248
 249 \begin{code}
 250 lookUp           :: FAST_STRING -> Bool
 251 lookup_int       :: String -> Maybe Int
 252 lookup_def_int   :: String -> Int -> Int
 253 lookup_def_float :: String -> Float -> Float
 254 lookup_str       :: String -> Maybe String
 255
 256 lookUp     sw = maybeToBool (assoc_opts sw)
 257
 258 lookup_str sw = firstJust (map (startsWith sw) unpacked_opts)
 259
 260 lookup_int sw = case (lookup_str sw) of
 261                   Nothing -> Nothing
 262                   Just xx -> Just (read xx)
 263
 264 lookup_def_int sw def = case (lookup_str sw) of
 265                             Nothing -> def              -- Use default
 266                             Just xx -> read xx
 267
 268 lookup_def_float sw def = case (lookup_str sw) of
 269                             Nothing -> def              -- Use default
 270                             Just xx -> read xx
 271
 272 assoc_opts    = assocMaybe [ (a, True) | a <- argv ]
 273 unpacked_opts = map _UNPK_ argv
 274
 275 {-
 276  Putting the compiler options into temporary at-files
 277  may turn out to be necessary later on if we turn hsc into
 278  a pure Win32 application where I think there's a command-line
 279  length limit of 255. unpacked_opts understands the @ option.
 280
 281 assoc_opts    = assocMaybe [ (_PK_ a, True) | a <- unpacked_opts ]
 282
 283 unpacked_opts :: [String]
 284 unpacked_opts =
 285   concat $
 286   map (expandAts) $
 287   map _UNPK_ argv
 288   where
 289    expandAts ('@':fname) = words (unsafePerformIO (readFile fname))
 290    expandAts l = [l]
 291 -}
 292 \end{code}
 293
 294 \begin{code}
 295 opt_AllStrict                   = lookUp  SLIT("-fall-strict")
 296 opt_AllowOverlappingInstances   = lookUp  SLIT("-fallow-overlapping-instances")
 297 opt_AutoSccsOnAllToplevs        = lookUp  SLIT("-fauto-sccs-on-all-toplevs")
 298 opt_AutoSccsOnExportedToplevs   = lookUp  SLIT("-fauto-sccs-on-exported-toplevs")
 299 opt_AutoSccsOnIndividualCafs    = lookUp  SLIT("-fauto-sccs-on-individual-cafs")
 300 opt_CompilingGhcInternals       = maybeToBool maybe_CompilingGhcInternals
 301 maybe_CompilingGhcInternals     = lookup_str "-fcompiling-ghc-internals="
 302 opt_D_dump_absC                 = lookUp  SLIT("-ddump-absC")
 303 opt_D_dump_asm                  = lookUp  SLIT("-ddump-asm")
 304 opt_D_dump_deriv                = lookUp  SLIT("-ddump-deriv")
 305 opt_D_dump_ds                   = lookUp  SLIT("-ddump-ds")
 306 opt_D_dump_flatC                = lookUp  SLIT("-ddump-flatC")
 307 opt_D_dump_occur_anal           = lookUp  SLIT("-ddump-occur-anal")
 308 opt_D_dump_rdr                  = lookUp  SLIT("-ddump-rdr")
 309 opt_D_dump_realC                = lookUp  SLIT("-ddump-realC")
 310 opt_D_dump_rn                   = lookUp  SLIT("-ddump-rn")
 311 opt_D_dump_simpl                = lookUp  SLIT("-ddump-simpl")
 312 opt_D_dump_simpl_iterations     = lookUp  SLIT("-ddump-simpl-iterations")
 313 opt_D_dump_spec                 = lookUp  SLIT("-ddump-spec")
 314 opt_D_dump_stg                  = lookUp  SLIT("-ddump-stg")
 315 opt_D_dump_stranal              = lookUp  SLIT("-ddump-stranal")
 316 opt_D_dump_tc                   = lookUp  SLIT("-ddump-tc")
 317 opt_D_show_passes               = lookUp  SLIT("-dshow-passes")
 318 opt_D_show_rn_trace             = lookUp  SLIT("-dshow-rn-trace")
 319 opt_D_show_rn_imports           = lookUp  SLIT("-dshow-rn-imports")
 320 opt_D_simplifier_stats          = lookUp  SLIT("-dsimplifier-stats")
 321 opt_D_source_stats              = lookUp  SLIT("-dsource-stats")
 322 opt_D_verbose_core2core         = lookUp  SLIT("-dverbose-simpl")
 323 opt_D_verbose_stg2stg           = lookUp  SLIT("-dverbose-stg")
 324 opt_DoCoreLinting               = lookUp  SLIT("-dcore-lint")
 325 opt_DoStgLinting                = lookUp  SLIT("-dstg-lint")
 326 opt_DoSemiTagging               = lookUp  SLIT("-fsemi-tagging")
 327 opt_DoTickyProfiling            = lookUp  SLIT("-fticky-ticky")
 328 opt_DoEtaReduction              = lookUp  SLIT("-fdo-eta-reduction")
 329 opt_EnsureSplittableC           = lookUp  SLIT("-fglobalise-toplev-names")
 330 opt_FoldrBuildOn                = lookUp  SLIT("-ffoldr-build-on")
 331 opt_ForConcurrent               = lookUp  SLIT("-fconcurrent")
 332 opt_GranMacros                  = lookUp  SLIT("-fgransim")
 333 opt_GlasgowExts                 = lookUp  SLIT("-fglasgow-exts")
 334 opt_HiMap                       = lookup_str "-himap="  -- file saying where to look for .hi files
 335 opt_IgnoreIfacePragmas          = lookUp  SLIT("-fignore-interface-pragmas")
 336 opt_IrrefutableTuples           = lookUp  SLIT("-firrefutable-tuples")
 337 opt_MultiParamClasses           = opt_GlasgowExts
 338 opt_NoImplicitPrelude           = lookUp  SLIT("-fno-implicit-prelude")
 339 opt_NoHiCheck                   = lookUp  SLIT("-fno-hi-version-check")
 340 opt_NumbersStrict               = lookUp  SLIT("-fnumbers-strict")
 341 opt_OmitBlackHoling             = lookUp  SLIT("-dno-black-holing")
 342 opt_OmitInterfacePragmas        = lookUp  SLIT("-fomit-interface-pragmas")
 343 opt_PprStyle_All                = lookUp  SLIT("-dppr-all")
 344 opt_PprStyle_Debug              = lookUp  SLIT("-dppr-debug")
 345 opt_PprStyle_User               = lookUp  SLIT("-dppr-user")
 346 opt_PprUserLength               = lookup_def_int "-dppr-user-length" 5 --ToDo: give this a name
 347 opt_ProduceC                    = lookup_str "-C="
 348 opt_ProduceS                    = lookup_str "-S="
 349 opt_ProduceHi                   = lookup_str "-hifile=" -- the one to produce this time
 350 opt_ReportWhyUnfoldingsDisallowed= lookUp SLIT("-freport-disallowed-unfoldings")
 351 opt_SccProfilingOn              = lookUp  SLIT("-fscc-profiling")
 352 opt_ShowImportSpecs             = lookUp  SLIT("-fshow-import-specs")
 353 opt_SigsRequired                = lookUp  SLIT("-fsignatures-required")
 354 opt_SourceUnchanged             = lookUp  SLIT("-fsource-unchanged")
 355 opt_SpecialiseAll               = lookUp  SLIT("-fspecialise-all")
 356 opt_SpecialiseImports           = lookUp  SLIT("-fspecialise-imports")
 357 opt_SpecialiseOverloaded        = lookUp  SLIT("-fspecialise-overloaded")
 358 opt_SpecialiseTrace             = lookUp  SLIT("-ftrace-specialisation")
 359 opt_SpecialiseUnboxed           = lookUp  SLIT("-fspecialise-unboxed")
 360 opt_StgDoLetNoEscapes           = lookUp  SLIT("-flet-no-escape")
 361 opt_ReturnInRegsThreshold       = lookup_int "-freturn-in-regs-threshold"
 362 opt_SccGroup                    = lookup_str "-G="
 363 opt_Verbose                     = lookUp  SLIT("-v")
 364
 365 opt_InterfaceUnfoldThreshold    = lookup_def_int "-funfolding-interface-threshold" iNTERFACE_UNFOLD_THRESHOLD
 366 opt_UnfoldingCreationThreshold  = lookup_def_int "-funfolding-creation-threshold"  uNFOLDING_CREATION_THRESHOLD
 367 opt_UnfoldingUseThreshold       = lookup_def_int "-funfolding-use-threshold"       uNFOLDING_USE_THRESHOLD
 368 opt_UnfoldingConDiscount        = lookup_def_int "-funfolding-con-discount"        uNFOLDING_CON_DISCOUNT_WEIGHT
 369
 370 opt_LiberateCaseThreshold       = lookup_def_int "-fliberate-case-threshold"       lIBERATE_CASE_THRESHOLD
 371 opt_UnfoldingKeenessFactor      = lookup_def_float "-funfolding-keeness-factor"    uNFOLDING_KEENESS_FACTOR
 372 opt_WarnNameShadowing           = lookUp  SLIT("-fwarn-name-shadowing")
 373 opt_WarnHiShadows               = lookUp  SLIT("-fwarn-hi-shadowing")
 374 opt_WarnIncompletePatterns      = lookUp  SLIT("-fwarn-incomplete-patterns")
 375 opt_WarnOverlappingPatterns     = lookUp  SLIT("-fwarn-overlapping-patterns")
 376 opt_WarnSimplePatterns          = lookUp  SLIT("-fwarn-simple-patterns")
 377 opt_WarnUnusedMatches           = lookUp  SLIT("-fwarn-unused-matches")
 378 opt_WarnUnusedBinds             = lookUp  SLIT("-fwarn-unused-binds")
 379 opt_WarnUnusedImports           = lookUp  SLIT("-fwarn-unused-imports")
 380 opt_WarnMissingMethods          = lookUp  SLIT("-fwarn-missing-methods")
 381 opt_WarnDuplicateExports        = lookUp  SLIT("-fwarn-duplicate-exports")
 382 opt_PruneTyDecls                = not (lookUp SLIT("-fno-prune-tydecls"))
 383 opt_PruneInstDecls              = not (lookUp SLIT("-fno-prune-instdecls"))
 384 opt_D_show_rn_stats             = lookUp SLIT("-dshow-rn-stats")
 385
 386 -- opt_UnfoldingOverrideThreshold       = lookup_int "-funfolding-override-threshold"
 387 \end{code}
 388
 389 \begin{code}
 390 classifyOpts :: ([CoreToDo],    -- Core-to-Core processing spec
 391                  [StgToDo])     -- STG-to-STG   processing spec
 392
 393 classifyOpts = sep argv [] [] -- accumulators...
 394   where
 395     sep :: [FAST_STRING]                 -- cmd-line opts (input)
 396         -> [CoreToDo] -> [StgToDo]       -- to_do accumulators
 397         -> ([CoreToDo], [StgToDo])       -- result
 398
 399     sep [] core_td stg_td -- all done!
 400       = (reverse core_td, reverse stg_td)
 401
 402 #       define CORE_TD(to_do) sep opts (to_do:core_td) stg_td
 403 #       define STG_TD(to_do)  sep opts core_td (to_do:stg_td)
 404
 405     sep (opt1:opts) core_td stg_td
 406       = case (_UNPK_ opt1) of -- the non-"just match a string" options are at the end...
 407           ',' : _       -> sep opts core_td stg_td -- it is for the parser
 408
 409           "-fsimplify"  -> -- gather up SimplifierSwitches specially...
 410                            simpl_sep opts defaultSimplSwitches core_td stg_td
 411
 412           "-fcalc-inlinings1"-> CORE_TD(CoreDoCalcInlinings1)
 413           "-fcalc-inlinings2"-> CORE_TD(CoreDoCalcInlinings2)
 414           "-ffloat-inwards"  -> CORE_TD(CoreDoFloatInwards)
 415           "-ffull-laziness"  -> CORE_TD(CoreDoFullLaziness)
 416           "-fliberate-case"  -> CORE_TD(CoreLiberateCase)
 417           "-fprint-core"     -> CORE_TD(CoreDoPrintCore)
 418           "-fstatic-args"    -> CORE_TD(CoreDoStaticArgs)
 419           "-fstrictness"     -> CORE_TD(CoreDoStrictness)
 420           "-fspecialise"     -> CORE_TD(CoreDoSpecialising)
 421           "-ffoldr-build-worker-wrapper"  -> CORE_TD(CoreDoFoldrBuildWorkerWrapper)
 422           "-ffoldr-build-ww-anal"  -> CORE_TD(CoreDoFoldrBuildWWAnal)
 423
 424           "-fstg-static-args" -> STG_TD(StgDoStaticArgs)
 425           "-fupdate-analysis" -> STG_TD(StgDoUpdateAnalysis)
 426           "-dstg-stats"       -> STG_TD(D_stg_stats)
 427           "-flambda-lift"     -> STG_TD(StgDoLambdaLift)
 428           "-fmassage-stg-for-profiling" -> STG_TD(StgDoMassageForProfiling)
 429
 430           _ -> -- NB: the driver is really supposed to handle bad options
 431                sep opts core_td stg_td
 432
 433     ----------------
 434
 435     simpl_sep :: [FAST_STRING]            -- cmd-line opts (input)
 436               -> [SimplifierSwitch]       -- simplifier-switch accumulator
 437               -> [CoreToDo] -> [StgToDo]  -- to_do accumulators
 438               -> ([CoreToDo], [StgToDo])  -- result
 439
 440         -- "simpl_sep" tailcalls "sep" once it's seen one set
 441         -- of SimplifierSwitches for a CoreDoSimplify.
 442
 443 #ifdef DEBUG
 444     simpl_sep input@[] simpl_sw core_td stg_td
 445       = panic "simpl_sep []"
 446 #endif
 447
 448         -- The SimplifierSwitches should be delimited by "[" and "]".
 449
 450     simpl_sep (opt1:opts) simpl_sw core_td stg_td
 451       = case (_UNPK_ opt1) of
 452           "[" -> simpl_sep opts simpl_sw core_td stg_td
 453           "]" -> let
 454                     this_simpl = CoreDoSimplify (isAmongSimpl simpl_sw)
 455                  in
 456                  sep opts (this_simpl : core_td) stg_td
 457
 458 #         define SIMPL_SW(sw) simpl_sep opts (sw:simpl_sw) core_td stg_td
 459
 460           -- the non-"just match a string" options are at the end...
 461           "-fshow-simplifier-progress"      -> SIMPL_SW(ShowSimplifierProgress)
 462           "-fcode-duplication-ok"           -> SIMPL_SW(SimplOkToDupCode)
 463           "-ffloat-lets-exposing-whnf"      -> SIMPL_SW(SimplFloatLetsExposingWHNF)
 464           "-ffloat-primops-ok"              -> SIMPL_SW(SimplOkToFloatPrimOps)
 465           "-falways-float-lets-from-lets"   -> SIMPL_SW(SimplAlwaysFloatLetsFromLets)
 466           "-fdo-case-elim"                  -> SIMPL_SW(SimplDoCaseElim)
 467           "-fdo-lambda-eta-expansion"       -> SIMPL_SW(SimplDoLambdaEtaExpansion)
 468           "-fdo-foldr-build"                -> SIMPL_SW(SimplDoFoldrBuild)
 469           "-fdo-not-fold-back-append"       -> SIMPL_SW(SimplDontFoldBackAppend)
 470           "-fdo-arity-expand"               -> SIMPL_SW(SimplDoArityExpand)
 471           "-fdo-inline-foldr-build"         -> SIMPL_SW(SimplDoInlineFoldrBuild)
 472           "-freuse-con"                     -> SIMPL_SW(SimplReuseCon)
 473           "-fcase-of-case"                  -> SIMPL_SW(SimplCaseOfCase)
 474           "-fcase-merge"                    -> SIMPL_SW(SimplCaseMerge)
 475           "-flet-to-case"                   -> SIMPL_SW(SimplLetToCase)
 476           "-fpedantic-bottoms"              -> SIMPL_SW(SimplPedanticBottoms)
 477           "-fmay-delete-conjurable-ids"     -> SIMPL_SW(SimplMayDeleteConjurableIds)
 478           "-fessential-unfoldings-only"     -> SIMPL_SW(EssentialUnfoldingsOnly)
 479           "-fignore-inline-pragma"          -> SIMPL_SW(IgnoreINLINEPragma)
 480           "-fno-let-from-case"              -> SIMPL_SW(SimplNoLetFromCase)
 481           "-fno-let-from-app"               -> SIMPL_SW(SimplNoLetFromApp)
 482           "-fno-let-from-strict-let"        -> SIMPL_SW(SimplNoLetFromStrictLet)
 483           "-fclone-binds"                   -> SIMPL_SW(SimplCloneBinds)
 484
 485           o | starts_with_msi  -> SIMPL_SW(MaxSimplifierIterations (read after_msi))
 486            where
 487             maybe_msi           = startsWith "-fmax-simplifier-iterations"   o
 488             starts_with_msi     = maybeToBool maybe_msi
 489             (Just after_msi)    = maybe_msi
 490
 491           _ -> -- NB: the driver is really supposed to handle bad options
 492                simpl_sep opts simpl_sw core_td stg_td
 493 \end{code}
 494
 495 %************************************************************************
 496 %*                                                                      *
 497 \subsection{Switch ordering}
 498 %*                                                                      *
 499 %************************************************************************
 500
 501 In spite of the @Produce*@ and @SccGroup@ constructors, these things
 502 behave just like enumeration types.
 503
 504 \begin{code}
 505 instance Eq SimplifierSwitch where
 506     a == b = tagOf_SimplSwitch a _EQ_ tagOf_SimplSwitch b
 507
 508 instance Ord SimplifierSwitch where
 509     a <  b  = tagOf_SimplSwitch a _LT_ tagOf_SimplSwitch b
 510     a <= b  = tagOf_SimplSwitch a _LE_ tagOf_SimplSwitch b
 511
 512 tagOf_SimplSwitch SimplOkToDupCode              =(ILIT(0) :: FAST_INT)
 513 tagOf_SimplSwitch SimplFloatLetsExposingWHNF    = ILIT(1)
 514 tagOf_SimplSwitch SimplOkToFloatPrimOps         = ILIT(2)
 515 tagOf_SimplSwitch SimplAlwaysFloatLetsFromLets  = ILIT(3)
 516 tagOf_SimplSwitch SimplDoCaseElim               = ILIT(4)
 517 tagOf_SimplSwitch SimplReuseCon                 = ILIT(5)
 518 tagOf_SimplSwitch SimplCaseOfCase               = ILIT(6)
 519 tagOf_SimplSwitch SimplLetToCase                = ILIT(7)
 520 tagOf_SimplSwitch SimplMayDeleteConjurableIds   = ILIT(9)
 521 tagOf_SimplSwitch SimplPedanticBottoms          = ILIT(10)
 522 tagOf_SimplSwitch SimplDoArityExpand            = ILIT(11)
 523 tagOf_SimplSwitch SimplDoFoldrBuild             = ILIT(12)
 524 tagOf_SimplSwitch SimplDoInlineFoldrBuild       = ILIT(14)
 525 tagOf_SimplSwitch IgnoreINLINEPragma            = ILIT(15)
 526 tagOf_SimplSwitch SimplDoLambdaEtaExpansion     = ILIT(16)
 527 tagOf_SimplSwitch EssentialUnfoldingsOnly       = ILIT(19)
 528 tagOf_SimplSwitch ShowSimplifierProgress        = ILIT(20)
 529 tagOf_SimplSwitch (MaxSimplifierIterations _)   = ILIT(21)
 530 tagOf_SimplSwitch SimplNoLetFromCase            = ILIT(27)
 531 tagOf_SimplSwitch SimplNoLetFromApp             = ILIT(28)
 532 tagOf_SimplSwitch SimplNoLetFromStrictLet       = ILIT(29)
 533 tagOf_SimplSwitch SimplDontFoldBackAppend       = ILIT(30)
 534 tagOf_SimplSwitch SimplCaseMerge                = ILIT(31)
 535 tagOf_SimplSwitch SimplCaseScrutinee            = ILIT(32)
 536 tagOf_SimplSwitch SimplCloneBinds               = ILIT(33)
 537
 538 -- If you add anything here, be sure to change lAST_SIMPL_SWITCH_TAG, too!
 539
 540 tagOf_SimplSwitch _ = panic# "tagOf_SimplSwitch"
 541
 542 lAST_SIMPL_SWITCH_TAG = IBOX(tagOf_SimplSwitch SimplCloneBinds)
 543 \end{code}
 544
 545 %************************************************************************
 546 %*                                                                      *
 547 \subsection{Switch lookup}
 548 %*                                                                      *
 549 %************************************************************************
 550
 551 \begin{code}
 552 isAmongSimpl :: [SimplifierSwitch] -> SimplifierSwitch -> SwitchResult
 553
 554 isAmongSimpl on_switches                -- Switches mentioned later occur *earlier*
 555                                         -- in the list; defaults right at the end.
 556   = let
 557         tidied_on_switches = foldl rm_dups [] on_switches
 558                 -- The fold*l* ensures that we keep the latest switches;
 559                 -- ie the ones that occur earliest in the list.
 560
 561         sw_tbl :: Array Int SwitchResult
 562
 563         sw_tbl = (array (0, lAST_SIMPL_SWITCH_TAG) -- bounds...
 564                         all_undefined)
 565                  // defined_elems
 566
 567         all_undefined = [ (i, SwBool False) | i <- [0 .. lAST_SIMPL_SWITCH_TAG ] ]
 568
 569         defined_elems = map mk_assoc_elem tidied_on_switches
 570     in
 571     -- (avoid some unboxing, bounds checking, and other horrible things:)
 572     case sw_tbl of { Array bounds_who_needs_'em stuff ->
 573     \ switch ->
 574         case (indexArray# stuff (tagOf_SimplSwitch switch)) of
 575           Lift v -> v
 576     }
 577   where
 578     mk_assoc_elem k@(MaxSimplifierIterations lvl)       = (IBOX(tagOf_SimplSwitch k), SwInt lvl)
 579
 580     mk_assoc_elem k = (IBOX(tagOf_SimplSwitch k), SwBool True) -- I'm here, Mom!
 581
 582     -- cannot have duplicates if we are going to use the array thing
 583     rm_dups switches_so_far switch
 584       = if switch `is_elem` switches_so_far
 585         then switches_so_far
 586         else switch : switches_so_far
 587       where
 588         sw `is_elem` []     = False
 589         sw `is_elem` (s:ss) = (tagOf_SimplSwitch sw) _EQ_ (tagOf_SimplSwitch s)
 590                             || sw `is_elem` ss
 591 \end{code}
 592
 593 Default settings for simplifier switches
 594
 595 \begin{code}
 596 defaultSimplSwitches = [MaxSimplifierIterations         1
 597                        ]
 598 \end{code}
 599
 600 %************************************************************************
 601 %*                                                                      *
 602 \subsection{Misc functions for command-line options}
 603 %*                                                                      *
 604 %************************************************************************
 605
 606
 607 \begin{code}
 608 switchIsOn :: (switch -> SwitchResult) -> switch -> Bool
 609
 610 switchIsOn lookup_fn switch
 611   = case (lookup_fn switch) of
 612       SwBool False -> False
 613       _            -> True
 614
 615 intSwitchSet :: (switch -> SwitchResult)
 616              -> (Int -> switch)
 617              -> Maybe Int
 618
 619 intSwitchSet lookup_fn switch
 620   = case (lookup_fn (switch (panic "intSwitchSet"))) of
 621       SwInt int -> Just int
 622       _         -> Nothing
 623 \end{code}