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