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