ghc/compiler/main/CmdLineOpts.lhs

   1 %
   2 % (c) The AQUA Project, Glasgow University, 1996-98
   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         opt_AllStrict,
  18         opt_AllowOverlappingInstances,
  19         opt_AllowUndecidableInstances,
  20         opt_AutoSccsOnAllToplevs,
  21         opt_AutoSccsOnExportedToplevs,
  22         opt_AutoSccsOnIndividualCafs,
  23         opt_D_dump_absC,
  24         opt_D_dump_asm,
  25         opt_D_dump_deriv,
  26         opt_D_dump_ds,
  27         opt_D_dump_flatC,
  28         opt_D_dump_inlinings,
  29         opt_D_dump_foreign,
  30         opt_D_dump_occur_anal,
  31         opt_D_dump_rdr,
  32         opt_D_dump_realC,
  33         opt_D_dump_rn,
  34         opt_D_dump_simpl,
  35         opt_D_dump_simpl_iterations,
  36         opt_D_dump_spec,
  37         opt_D_dump_stg,
  38         opt_D_dump_stranal,
  39         opt_D_dump_tc,
  40         opt_D_show_passes,
  41         opt_D_show_rn_trace,
  42         opt_D_show_rn_imports,
  43         opt_D_simplifier_stats,
  44         opt_D_source_stats,
  45         opt_D_verbose_core2core,
  46         opt_D_verbose_stg2stg,
  47         opt_DictsStrict,
  48         opt_DoCoreLinting,
  49         opt_DoStgLinting,
  50         opt_DoSemiTagging,
  51         opt_DoEtaReduction,
  52         opt_DoTickyProfiling,
  53         opt_EmitCExternDecls,
  54         opt_EnsureSplittableC,
  55         opt_FoldrBuildOn,
  56         opt_GlasgowExts,
  57         opt_GranMacros,
  58         opt_HiMap,
  59         opt_HiVersion,
  60         opt_IgnoreIfacePragmas,
  61         opt_IrrefutableTuples,
  62         opt_LiberateCaseThreshold,
  63         opt_MaxContextReductionDepth,
  64         opt_MultiParamClasses,
  65         opt_NoHiCheck,
  66         opt_NoImplicitPrelude,
  67         opt_NoPreInlining,
  68         opt_NumbersStrict,
  69         opt_OmitBlackHoling,
  70         opt_OmitInterfacePragmas,
  71         opt_PprStyle_NoPrags,
  72         opt_PprStyle_Debug,
  73         opt_PprUserLength,
  74         opt_ProduceC,
  75         opt_ProduceHi,
  76         opt_ProduceS,
  77         opt_ProduceExportCStubs,
  78         opt_ProduceExportHStubs,
  79         opt_ReportCompile,
  80         opt_SccGroup,
  81         opt_SccProfilingOn,
  82         opt_SourceUnchanged,
  83         opt_StgDoLetNoEscapes,
  84         opt_Parallel,
  85
  86         opt_InterfaceUnfoldThreshold,
  87         opt_UnfoldCasms,
  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_WarnMissingSigs,
 105         opt_PruneTyDecls, opt_PruneInstDecls,
 106         opt_D_show_rn_stats
 107     ) where
 108
 109 #include "HsVersions.h"
 110
 111 import Array    ( array, (//) )
 112 import GlaExts
 113 import Argv
 114 import Constants        -- Default values for some flags
 115
 116 import Maybes           ( assocMaybe, firstJust, maybeToBool )
 117 import Util             ( startsWith, panic, panic# )
 118
 119 #if __GLASGOW_HASKELL__ < 301
 120 import ArrBase  ( Array(..) )
 121 #else
 122 import PrelArr  ( Array(..) )
 123 #endif
 124 \end{code}
 125
 126 A command-line {\em switch} is (generally) either on or off; e.g., the
 127 ``verbose'' (-v) switch is either on or off.  (The \tr{-G<group>}
 128 switch is an exception; it's set to a string, or nothing.)
 129
 130 A list of {\em ToDo}s is things to be done in a particular part of
 131 processing.  A (fictitious) example for the Core-to-Core simplifier
 132 might be: run the simplifier, then run the strictness analyser, then
 133 run the simplifier again (three ``todos'').
 134
 135 There are three ``to-do processing centers'' at the moment.  In the
 136 main loop (\tr{main/Main.lhs}), in the Core-to-Core processing loop
 137 (\tr{simplCore/SimplCore.lhs), and in the STG-to-STG processing loop
 138 (\tr{simplStg/SimplStg.lhs}).
 139
 140 %************************************************************************
 141 %*                                                                      *
 142 \subsection{Datatypes associated with command-line options}
 143 %*                                                                      *
 144 %************************************************************************
 145
 146 \begin{code}
 147 data SwitchResult
 148   = SwBool      Bool            -- on/off
 149   | SwString    FAST_STRING     -- nothing or a String
 150   | SwInt       Int             -- nothing or an Int
 151 \end{code}
 152
 153 \begin{code}
 154 data CoreToDo           -- These are diff core-to-core passes,
 155                         -- which may be invoked in any order,
 156                         -- as many times as you like.
 157
 158   = CoreDoSimplify      -- The core-to-core simplifier.
 159         (SimplifierSwitch -> SwitchResult)
 160                         -- Each run of the simplifier can take a different
 161                         -- set of simplifier-specific flags.
 162   | CoreDoCalcInlinings1
 163   | CoreDoCalcInlinings2
 164   | CoreDoFloatInwards
 165   | CoreDoFullLaziness
 166   | CoreLiberateCase
 167   | CoreDoPrintCore
 168   | CoreDoStaticArgs
 169   | CoreDoStrictness
 170   | CoreDoSpecialising
 171   | CoreDoFoldrBuildWorkerWrapper
 172   | CoreDoFoldrBuildWWAnal
 173 \end{code}
 174
 175 \begin{code}
 176 data StgToDo
 177   = StgDoStaticArgs
 178   | StgDoUpdateAnalysis
 179   | StgDoLambdaLift
 180   | StgDoMassageForProfiling  -- should be (next to) last
 181   -- There's also setStgVarInfo, but its absolute "lastness"
 182   -- is so critical that it is hardwired in (no flag).
 183   | D_stg_stats
 184 \end{code}
 185
 186 \begin{code}
 187 data SimplifierSwitch
 188   = SimplOkToDupCode
 189   | SimplFloatLetsExposingWHNF
 190   | SimplOkToFloatPrimOps
 191   | SimplAlwaysFloatLetsFromLets
 192   | SimplDoCaseElim
 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   | MaxSimplifierIterations Int
 212
 213   | SimplNoLetFromCase      -- used when turning off floating entirely
 214   | SimplNoLetFromApp       -- (for experimentation only) WDP 95/10
 215   | SimplNoLetFromStrictLet
 216
 217   | SimplCaseMerge
 218   | SimplPleaseClone
 219 \end{code}
 220
 221 %************************************************************************
 222 %*                                                                      *
 223 \subsection{Classifying command-line options}
 224 %*                                                                      *
 225 %************************************************************************
 226
 227 \begin{code}
 228 lookUp           :: FAST_STRING -> Bool
 229 lookup_int       :: String -> Maybe Int
 230 lookup_def_int   :: String -> Int -> Int
 231 lookup_def_float :: String -> Float -> Float
 232 lookup_str       :: String -> Maybe String
 233
 234 lookUp     sw = maybeToBool (assoc_opts sw)
 235
 236 lookup_str sw = firstJust (map (startsWith sw) unpacked_opts)
 237
 238 lookup_int sw = case (lookup_str sw) of
 239                   Nothing -> Nothing
 240                   Just xx -> Just (read xx)
 241
 242 lookup_def_int sw def = case (lookup_str sw) of
 243                             Nothing -> def              -- Use default
 244                             Just xx -> read xx
 245
 246 lookup_def_float sw def = case (lookup_str sw) of
 247                             Nothing -> def              -- Use default
 248                             Just xx -> read xx
 249
 250 assoc_opts    = assocMaybe [ (a, True) | a <- argv ]
 251 unpacked_opts = map _UNPK_ argv
 252
 253 {-
 254  Putting the compiler options into temporary at-files
 255  may turn out to be necessary later on if we turn hsc into
 256  a pure Win32 application where I think there's a command-line
 257  length limit of 255. unpacked_opts understands the @ option.
 258
 259 assoc_opts    = assocMaybe [ (_PK_ a, True) | a <- unpacked_opts ]
 260
 261 unpacked_opts :: [String]
 262 unpacked_opts =
 263   concat $
 264   map (expandAts) $
 265   map _UNPK_ argv
 266   where
 267    expandAts ('@':fname) = words (unsafePerformIO (readFile fname))
 268    expandAts l = [l]
 269 -}
 270 \end{code}
 271
 272 \begin{code}
 273 opt_AllStrict                   = lookUp  SLIT("-fall-strict")
 274 opt_AllowOverlappingInstances   = lookUp  SLIT("-fallow-overlapping-instances")
 275 opt_AllowUndecidableInstances   = lookUp  SLIT("-fallow-undecidable-instances")
 276 opt_AutoSccsOnAllToplevs        = lookUp  SLIT("-fauto-sccs-on-all-toplevs")
 277 opt_AutoSccsOnExportedToplevs   = lookUp  SLIT("-fauto-sccs-on-exported-toplevs")
 278 opt_AutoSccsOnIndividualCafs    = lookUp  SLIT("-fauto-sccs-on-individual-cafs")
 279 opt_D_dump_absC                 = lookUp  SLIT("-ddump-absC")
 280 opt_D_dump_asm                  = lookUp  SLIT("-ddump-asm")
 281 opt_D_dump_deriv                = lookUp  SLIT("-ddump-deriv")
 282 opt_D_dump_ds                   = lookUp  SLIT("-ddump-ds")
 283 opt_D_dump_flatC                = lookUp  SLIT("-ddump-flatC")
 284 opt_D_dump_inlinings            = lookUp  SLIT("-ddump-inlinings")
 285 opt_D_dump_foreign              = lookUp  SLIT("-ddump-foreign-stubs")
 286 opt_D_dump_occur_anal           = lookUp  SLIT("-ddump-occur-anal")
 287 opt_D_dump_rdr                  = lookUp  SLIT("-ddump-rdr")
 288 opt_D_dump_realC                = lookUp  SLIT("-ddump-realC")
 289 opt_D_dump_rn                   = lookUp  SLIT("-ddump-rn")
 290 opt_D_dump_simpl                = lookUp  SLIT("-ddump-simpl")
 291 opt_D_dump_simpl_iterations     = lookUp  SLIT("-ddump-simpl-iterations")
 292 opt_D_dump_spec                 = lookUp  SLIT("-ddump-spec")
 293 opt_D_dump_stg                  = lookUp  SLIT("-ddump-stg")
 294 opt_D_dump_stranal              = lookUp  SLIT("-ddump-stranal")
 295 opt_D_dump_tc                   = lookUp  SLIT("-ddump-tc")
 296 opt_D_show_passes               = lookUp  SLIT("-dshow-passes")
 297 opt_D_show_rn_trace             = lookUp  SLIT("-dshow-rn-trace")
 298 opt_D_show_rn_imports           = lookUp  SLIT("-dshow-rn-imports")
 299 opt_D_simplifier_stats          = lookUp  SLIT("-dsimplifier-stats")
 300 opt_D_source_stats              = lookUp  SLIT("-dsource-stats")
 301 opt_D_verbose_core2core         = lookUp  SLIT("-dverbose-simpl")
 302 opt_D_verbose_stg2stg           = lookUp  SLIT("-dverbose-stg")
 303 opt_DictsStrict                 = lookUp  SLIT("-fdicts-strict")
 304 opt_DoCoreLinting               = lookUp  SLIT("-dcore-lint")
 305 opt_DoStgLinting                = lookUp  SLIT("-dstg-lint")
 306 opt_DoEtaReduction              = lookUp  SLIT("-fdo-eta-reduction")
 307 opt_DoSemiTagging               = lookUp  SLIT("-fsemi-tagging")
 308 opt_DoTickyProfiling            = lookUp  SLIT("-fticky-ticky")
 309 opt_EmitCExternDecls            = lookUp  SLIT("-femit-extern-decls")
 310 opt_EnsureSplittableC           = lookUp  SLIT("-fglobalise-toplev-names")
 311 opt_FoldrBuildOn                = lookUp  SLIT("-ffoldr-build-on")
 312 opt_GranMacros                  = lookUp  SLIT("-fgransim")
 313 opt_GlasgowExts                 = lookUp  SLIT("-fglasgow-exts")
 314 opt_HiMap                       = lookup_str "-himap="       -- file saying where to look for .hi files
 315 opt_HiVersion                   = lookup_def_int "-fhi-version=" 0 -- what version we're compiling.
 316 opt_IgnoreIfacePragmas          = lookUp  SLIT("-fignore-interface-pragmas")
 317 opt_IrrefutableTuples           = lookUp  SLIT("-firrefutable-tuples")
 318 opt_MaxContextReductionDepth    = lookup_def_int "-fcontext-stack" mAX_CONTEXT_REDUCTION_DEPTH
 319 opt_MultiParamClasses           = opt_GlasgowExts
 320 opt_NoHiCheck                   = lookUp  SLIT("-fno-hi-version-check")
 321 opt_NoImplicitPrelude           = lookUp  SLIT("-fno-implicit-prelude")
 322 opt_NoPreInlining               = lookUp  SLIT("-fno-pre-inlining")
 323 opt_NumbersStrict               = lookUp  SLIT("-fnumbers-strict")
 324 opt_OmitBlackHoling             = lookUp  SLIT("-dno-black-holing")
 325 opt_OmitInterfacePragmas        = lookUp  SLIT("-fomit-interface-pragmas")
 326 opt_PprStyle_NoPrags            = lookUp  SLIT("-dppr-noprags")
 327 opt_PprStyle_Debug              = lookUp  SLIT("-dppr-debug")
 328 opt_PprUserLength               = lookup_def_int "-dppr-user-length" 5 --ToDo: give this a name
 329 opt_ProduceC                    = lookup_str "-C="
 330 opt_ProduceS                    = lookup_str "-S="
 331 opt_ProduceExportCStubs         = lookup_str "-F="
 332 opt_ProduceExportHStubs         = lookup_str "-FH="
 333 opt_ProduceHi                   = lookup_str "-hifile=" -- the one to produce this time
 334 opt_ReportCompile                = lookUp SLIT("-freport-compile")
 335 opt_SccProfilingOn              = lookUp  SLIT("-fscc-profiling")
 336 opt_SourceUnchanged             = lookUp  SLIT("-fsource-unchanged")
 337 opt_StgDoLetNoEscapes           = lookUp  SLIT("-flet-no-escape")
 338 opt_Parallel                    = lookUp  SLIT("-fparallel")
 339 opt_SccGroup                    = lookup_str "-G="
 340 opt_Verbose                     = lookUp  SLIT("-v")
 341
 342 opt_UnfoldCasms                 = lookUp SLIT("-funfold-casms-in-hi-file")
 343 opt_InterfaceUnfoldThreshold    = lookup_def_int "-funfolding-interface-threshold" iNTERFACE_UNFOLD_THRESHOLD
 344 opt_UnfoldingCreationThreshold  = lookup_def_int "-funfolding-creation-threshold"  uNFOLDING_CREATION_THRESHOLD
 345 opt_UnfoldingUseThreshold       = lookup_def_int "-funfolding-use-threshold"       uNFOLDING_USE_THRESHOLD
 346 opt_UnfoldingConDiscount        = lookup_def_int "-funfolding-con-discount"        uNFOLDING_CON_DISCOUNT_WEIGHT
 347
 348 opt_LiberateCaseThreshold       = lookup_def_int "-fliberate-case-threshold"       lIBERATE_CASE_THRESHOLD
 349 opt_UnfoldingKeenessFactor      = lookup_def_float "-funfolding-keeness-factor"    uNFOLDING_KEENESS_FACTOR
 350 opt_WarnNameShadowing           = lookUp  SLIT("-fwarn-name-shadowing")
 351 opt_WarnHiShadows               = lookUp  SLIT("-fwarn-hi-shadowing")
 352 opt_WarnIncompletePatterns      = lookUp  SLIT("-fwarn-incomplete-patterns")
 353 opt_WarnOverlappingPatterns     = lookUp  SLIT("-fwarn-overlapping-patterns")
 354 opt_WarnSimplePatterns          = lookUp  SLIT("-fwarn-simple-patterns")
 355 opt_WarnUnusedMatches           = lookUp  SLIT("-fwarn-unused-matches")
 356 opt_WarnUnusedBinds             = lookUp  SLIT("-fwarn-unused-binds")
 357 opt_WarnUnusedImports           = lookUp  SLIT("-fwarn-unused-imports")
 358 opt_WarnMissingMethods          = lookUp  SLIT("-fwarn-missing-methods")
 359 opt_WarnDuplicateExports        = lookUp  SLIT("-fwarn-duplicate-exports")
 360 opt_WarnMissingSigs             = lookUp  SLIT("-fwarn-missing-signatures")
 361 opt_PruneTyDecls                = not (lookUp SLIT("-fno-prune-tydecls"))
 362 opt_PruneInstDecls              = not (lookUp SLIT("-fno-prune-instdecls"))
 363 opt_D_show_rn_stats             = lookUp SLIT("-dshow-rn-stats")
 364
 365 -- opt_UnfoldingOverrideThreshold       = lookup_int "-funfolding-override-threshold"
 366 \end{code}
 367
 368 \begin{code}
 369 classifyOpts :: ([CoreToDo],    -- Core-to-Core processing spec
 370                  [StgToDo])     -- STG-to-STG   processing spec
 371
 372 classifyOpts = sep argv [] [] -- accumulators...
 373   where
 374     sep :: [FAST_STRING]                 -- cmd-line opts (input)
 375         -> [CoreToDo] -> [StgToDo]       -- to_do accumulators
 376         -> ([CoreToDo], [StgToDo])       -- result
 377
 378     sep [] core_td stg_td -- all done!
 379       = (reverse core_td, reverse stg_td)
 380
 381 #       define CORE_TD(to_do) sep opts (to_do:core_td) stg_td
 382 #       define STG_TD(to_do)  sep opts core_td (to_do:stg_td)
 383
 384     sep (opt1:opts) core_td stg_td
 385       = case (_UNPK_ opt1) of -- the non-"just match a string" options are at the end...
 386           ',' : _       -> sep opts core_td stg_td -- it is for the parser
 387
 388           "-fsimplify"  -> -- gather up SimplifierSwitches specially...
 389                            simpl_sep opts defaultSimplSwitches core_td stg_td
 390
 391           "-fcalc-inlinings1"-> CORE_TD(CoreDoCalcInlinings1)
 392           "-fcalc-inlinings2"-> CORE_TD(CoreDoCalcInlinings2)
 393           "-ffloat-inwards"  -> CORE_TD(CoreDoFloatInwards)
 394           "-ffull-laziness"  -> CORE_TD(CoreDoFullLaziness)
 395           "-fliberate-case"  -> CORE_TD(CoreLiberateCase)
 396           "-fprint-core"     -> CORE_TD(CoreDoPrintCore)
 397           "-fstatic-args"    -> CORE_TD(CoreDoStaticArgs)
 398           "-fstrictness"     -> CORE_TD(CoreDoStrictness)
 399           "-fspecialise"     -> CORE_TD(CoreDoSpecialising)
 400           "-ffoldr-build-worker-wrapper"  -> CORE_TD(CoreDoFoldrBuildWorkerWrapper)
 401           "-ffoldr-build-ww-anal"  -> CORE_TD(CoreDoFoldrBuildWWAnal)
 402
 403           "-fstg-static-args" -> STG_TD(StgDoStaticArgs)
 404           "-fupdate-analysis" -> STG_TD(StgDoUpdateAnalysis)
 405           "-dstg-stats"       -> STG_TD(D_stg_stats)
 406           "-flambda-lift"     -> STG_TD(StgDoLambdaLift)
 407           "-fmassage-stg-for-profiling" -> STG_TD(StgDoMassageForProfiling)
 408
 409           _ -> -- NB: the driver is really supposed to handle bad options
 410                sep opts core_td stg_td
 411
 412     ----------------
 413
 414     simpl_sep :: [FAST_STRING]            -- cmd-line opts (input)
 415               -> [SimplifierSwitch]       -- simplifier-switch accumulator
 416               -> [CoreToDo] -> [StgToDo]  -- to_do accumulators
 417               -> ([CoreToDo], [StgToDo])  -- result
 418
 419         -- "simpl_sep" tailcalls "sep" once it's seen one set
 420         -- of SimplifierSwitches for a CoreDoSimplify.
 421
 422 #ifdef DEBUG
 423     simpl_sep input@[] simpl_sw core_td stg_td
 424       = panic "simpl_sep []"
 425 #endif
 426
 427         -- The SimplifierSwitches should be delimited by "[" and "]".
 428
 429     simpl_sep (opt1:opts) simpl_sw core_td stg_td
 430       = case (_UNPK_ opt1) of
 431           "[" -> simpl_sep opts simpl_sw core_td stg_td
 432           "]" -> let
 433                     this_simpl = CoreDoSimplify (isAmongSimpl simpl_sw)
 434                  in
 435                  sep opts (this_simpl : core_td) stg_td
 436
 437 #         define SIMPL_SW(sw) simpl_sep opts (sw:simpl_sw) core_td stg_td
 438
 439           -- the non-"just match a string" options are at the end...
 440           "-fcode-duplication-ok"           -> SIMPL_SW(SimplOkToDupCode)
 441           "-ffloat-lets-exposing-whnf"      -> SIMPL_SW(SimplFloatLetsExposingWHNF)
 442           "-ffloat-primops-ok"              -> SIMPL_SW(SimplOkToFloatPrimOps)
 443           "-falways-float-lets-from-lets"   -> SIMPL_SW(SimplAlwaysFloatLetsFromLets)
 444           "-fdo-case-elim"                  -> SIMPL_SW(SimplDoCaseElim)
 445           "-fdo-lambda-eta-expansion"       -> SIMPL_SW(SimplDoLambdaEtaExpansion)
 446           "-fdo-foldr-build"                -> SIMPL_SW(SimplDoFoldrBuild)
 447           "-fdo-arity-expand"               -> SIMPL_SW(SimplDoArityExpand)
 448           "-fdo-inline-foldr-build"         -> SIMPL_SW(SimplDoInlineFoldrBuild)
 449           "-fcase-of-case"                  -> SIMPL_SW(SimplCaseOfCase)
 450           "-fcase-merge"                    -> SIMPL_SW(SimplCaseMerge)
 451           "-flet-to-case"                   -> SIMPL_SW(SimplLetToCase)
 452           "-fpedantic-bottoms"              -> SIMPL_SW(SimplPedanticBottoms)
 453           "-fmay-delete-conjurable-ids"     -> SIMPL_SW(SimplMayDeleteConjurableIds)
 454           "-fessential-unfoldings-only"     -> SIMPL_SW(EssentialUnfoldingsOnly)
 455           "-fignore-inline-pragma"          -> SIMPL_SW(IgnoreINLINEPragma)
 456           "-fno-let-from-case"              -> SIMPL_SW(SimplNoLetFromCase)
 457           "-fno-let-from-app"               -> SIMPL_SW(SimplNoLetFromApp)
 458           "-fno-let-from-strict-let"        -> SIMPL_SW(SimplNoLetFromStrictLet)
 459           "-fclone-binds"                   -> SIMPL_SW(SimplPleaseClone)
 460
 461           o | starts_with_msi  -> SIMPL_SW(MaxSimplifierIterations (read after_msi))
 462            where
 463             maybe_msi           = startsWith "-fmax-simplifier-iterations"   o
 464             starts_with_msi     = maybeToBool maybe_msi
 465             (Just after_msi)    = maybe_msi
 466
 467           _ -> -- NB: the driver is really supposed to handle bad options
 468                simpl_sep opts simpl_sw core_td stg_td
 469 \end{code}
 470
 471 %************************************************************************
 472 %*                                                                      *
 473 \subsection{Switch ordering}
 474 %*                                                                      *
 475 %************************************************************************
 476
 477 In spite of the @Produce*@ and @SccGroup@ constructors, these things
 478 behave just like enumeration types.
 479
 480 \begin{code}
 481 instance Eq SimplifierSwitch where
 482     a == b = tagOf_SimplSwitch a _EQ_ tagOf_SimplSwitch b
 483
 484 instance Ord SimplifierSwitch where
 485     a <  b  = tagOf_SimplSwitch a _LT_ tagOf_SimplSwitch b
 486     a <= b  = tagOf_SimplSwitch a _LE_ tagOf_SimplSwitch b
 487
 488 tagOf_SimplSwitch SimplOkToDupCode              =(ILIT(0) :: FAST_INT)
 489 tagOf_SimplSwitch SimplFloatLetsExposingWHNF    = ILIT(1)
 490 tagOf_SimplSwitch SimplOkToFloatPrimOps         = ILIT(2)
 491 tagOf_SimplSwitch SimplAlwaysFloatLetsFromLets  = ILIT(3)
 492 tagOf_SimplSwitch SimplDoCaseElim               = ILIT(4)
 493 tagOf_SimplSwitch SimplCaseOfCase               = ILIT(6)
 494 tagOf_SimplSwitch SimplLetToCase                = ILIT(7)
 495 tagOf_SimplSwitch SimplMayDeleteConjurableIds   = ILIT(9)
 496 tagOf_SimplSwitch SimplPedanticBottoms          = ILIT(10)
 497 tagOf_SimplSwitch SimplDoArityExpand            = ILIT(11)
 498 tagOf_SimplSwitch SimplDoFoldrBuild             = ILIT(12)
 499 tagOf_SimplSwitch SimplDoInlineFoldrBuild       = ILIT(14)
 500 tagOf_SimplSwitch IgnoreINLINEPragma            = ILIT(15)
 501 tagOf_SimplSwitch SimplDoLambdaEtaExpansion     = ILIT(16)
 502 tagOf_SimplSwitch EssentialUnfoldingsOnly       = ILIT(19)
 503 tagOf_SimplSwitch (MaxSimplifierIterations _)   = ILIT(21)
 504 tagOf_SimplSwitch SimplNoLetFromCase            = ILIT(27)
 505 tagOf_SimplSwitch SimplNoLetFromApp             = ILIT(28)
 506 tagOf_SimplSwitch SimplNoLetFromStrictLet       = ILIT(29)
 507 tagOf_SimplSwitch SimplCaseMerge                = ILIT(31)
 508 tagOf_SimplSwitch SimplPleaseClone              = 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 SimplPleaseClone)
 515 \end{code}
 516
 517 %************************************************************************
 518 %*                                                                      *
 519 \subsection{Switch lookup}
 520 %*                                                                      *
 521 %************************************************************************
 522
 523 \begin{code}
 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, 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 #if __GLASGOW_HASKELL__ < 400
 548           Lift v -> v
 549 #else
 550           (# _, v #) -> v
 551 #endif
 552     }
 553   where
 554     mk_assoc_elem k@(MaxSimplifierIterations lvl)       = (IBOX(tagOf_SimplSwitch k), SwInt lvl)
 555
 556     mk_assoc_elem k = (IBOX(tagOf_SimplSwitch k), SwBool True) -- I'm here, Mom!
 557
 558     -- cannot have duplicates if we are going to use the array thing
 559     rm_dups switches_so_far switch
 560       = if switch `is_elem` switches_so_far
 561         then switches_so_far
 562         else switch : switches_so_far
 563       where
 564         sw `is_elem` []     = False
 565         sw `is_elem` (s:ss) = (tagOf_SimplSwitch sw) _EQ_ (tagOf_SimplSwitch s)
 566                             || sw `is_elem` ss
 567 \end{code}
 568
 569 Default settings for simplifier switches
 570
 571 \begin{code}
 572 defaultSimplSwitches = [MaxSimplifierIterations         1
 573                        ]
 574 \end{code}
 575
 576 %************************************************************************
 577 %*                                                                      *
 578 \subsection{Misc functions for command-line options}
 579 %*                                                                      *
 580 %************************************************************************
 581
 582
 583 \begin{code}
 584 switchIsOn :: (switch -> SwitchResult) -> switch -> Bool
 585
 586 switchIsOn lookup_fn switch
 587   = case (lookup_fn switch) of
 588       SwBool False -> False
 589       _            -> True
 590
 591 intSwitchSet :: (switch -> SwitchResult)
 592              -> (Int -> switch)
 593              -> Maybe Int
 594
 595 intSwitchSet lookup_fn switch
 596   = case (lookup_fn (switch (panic "intSwitchSet"))) of
 597       SwInt int -> Just int
 598       _         -> Nothing
 599 \end{code}