ghc/compiler/main/CmdLineOpts.lhs

   1 %
   2 % (c) The University of Glasgow, 1996-2000
   3 %
   4 \section[CmdLineOpts]{Things to do with command-line options}
   5
   6 \begin{code}
   7
   8 module CmdLineOpts (
   9         CoreToDo(..),
  10         SimplifierSwitch(..), isAmongSimpl,
  11         StgToDo(..),
  12         SwitchResult(..),
  13         HscLang(..),
  14         DynFlag(..),    -- needed non-abstractly by DriverFlags
  15         DynFlags(..),
  16
  17         intSwitchSet,
  18         switchIsOn,
  19         isStaticHscFlag,
  20
  21         opt_PprStyle_NoPrags,
  22         opt_PprUserLength,
  23         opt_PprStyle_Debug,
  24
  25         dopt,
  26
  27         -- other dynamic flags
  28         dopt_CoreToDo,
  29         dopt_StgToDo,
  30
  31         -- profiling opts
  32         opt_AutoSccsOnAllToplevs,
  33         opt_AutoSccsOnExportedToplevs,
  34         opt_AutoSccsOnIndividualCafs,
  35         opt_AutoSccsOnDicts,
  36         opt_SccProfilingOn,
  37         opt_DoTickyProfiling,
  38
  39         -- language opts
  40         opt_AllStrict,
  41         opt_DictsStrict,
  42         opt_MaxContextReductionDepth,
  43         opt_Generics,
  44         opt_IrrefutableTuples,
  45         opt_NumbersStrict,
  46         opt_Parallel,
  47         opt_SMP,
  48
  49         -- optimisation opts
  50         opt_DoSemiTagging,
  51         opt_FoldrBuildOn,
  52         opt_LiberateCaseThreshold,
  53         opt_StgDoLetNoEscapes,
  54         opt_UnfoldCasms,
  55         opt_UsageSPOn,
  56         opt_UnboxStrictFields,
  57         opt_SimplNoPreInlining,
  58         opt_SimplDoEtaReduction,
  59         opt_SimplDoLambdaEtaExpansion,
  60         opt_SimplCaseOfCase,
  61         opt_SimplCaseMerge,
  62         opt_SimplPedanticBottoms,
  63         opt_SimplExcessPrecision,
  64
  65         -- Unfolding control
  66         opt_UF_HiFileThreshold,
  67         opt_UF_CreationThreshold,
  68         opt_UF_UseThreshold,
  69         opt_UF_FunAppDiscount,
  70         opt_UF_KeenessFactor,
  71         opt_UF_UpdateInPlace,
  72         opt_UF_CheapOp,
  73         opt_UF_DearOp,
  74
  75         -- misc opts
  76         opt_InPackage,
  77         opt_EmitCExternDecls,
  78         opt_EnsureSplittableC,
  79         opt_GranMacros,
  80         opt_HiVersion,
  81         opt_HistorySize,
  82         opt_IgnoreAsserts,
  83         opt_IgnoreIfacePragmas,
  84         opt_NoHiCheck,
  85         opt_NoImplicitPrelude,
  86         opt_OmitBlackHoling,
  87         opt_OmitInterfacePragmas,
  88         opt_NoPruneTyDecls,
  89         opt_NoPruneDecls,
  90         opt_ReportCompile,
  91         opt_Static,
  92         opt_Unregisterised,
  93         opt_Verbose,
  94
  95         -- Code generation
  96         opt_UseVanillaRegs,
  97         opt_UseFloatRegs,
  98         opt_UseDoubleRegs,
  99         opt_UseLongRegs
 100     ) where
 101
 102 #include "HsVersions.h"
 103
 104 import Array    ( array, (//) )
 105 import GlaExts
 106 import Argv
 107 import Constants        -- Default values for some flags
 108 import Util
 109 import FastTypes
 110
 111 import Maybes           ( firstJust )
 112 import Panic            ( panic )
 113
 114 #if __GLASGOW_HASKELL__ < 301
 115 import ArrBase  ( Array(..) )
 116 #else
 117 import PrelArr  ( Array(..) )
 118 #endif
 119 \end{code}
 120
 121 %************************************************************************
 122 %*                                                                      *
 123 \subsection{Command-line options}
 124 %*                                                                      *
 125 %************************************************************************
 126
 127 The hsc command-line options are split into two categories:
 128
 129   - static flags
 130   - dynamic flags
 131
 132 Static flags are represented by top-level values of type Bool or Int,
 133 for example.  They therefore have the same value throughout the
 134 invocation of hsc.
 135
 136 Dynamic flags are represented by an abstract type, DynFlags, which is
 137 passed into hsc by the compilation manager for every compilation.
 138 Dynamic flags are those that change on a per-compilation basis,
 139 perhaps because they may be present in the OPTIONS pragma at the top
 140 of a module.
 141
 142 Other flag-related blurb:
 143
 144 A list of {\em ToDo}s is things to be done in a particular part of
 145 processing.  A (fictitious) example for the Core-to-Core simplifier
 146 might be: run the simplifier, then run the strictness analyser, then
 147 run the simplifier again (three ``todos'').
 148
 149 There are three ``to-do processing centers'' at the moment.  In the
 150 main loop (\tr{main/Main.lhs}), in the Core-to-Core processing loop
 151 (\tr{simplCore/SimplCore.lhs), and in the STG-to-STG processing loop
 152 (\tr{simplStg/SimplStg.lhs}).
 153
 154 %************************************************************************
 155 %*                                                                      *
 156 \subsection{Datatypes associated with command-line options}
 157 %*                                                                      *
 158 %************************************************************************
 159
 160 \begin{code}
 161 data SwitchResult
 162   = SwBool      Bool            -- on/off
 163   | SwString    FAST_STRING     -- nothing or a String
 164   | SwInt       Int             -- nothing or an Int
 165 \end{code}
 166
 167 \begin{code}
 168 data CoreToDo           -- These are diff core-to-core passes,
 169                         -- which may be invoked in any order,
 170                         -- as many times as you like.
 171
 172   = CoreDoSimplify      -- The core-to-core simplifier.
 173         (SimplifierSwitch -> SwitchResult)
 174                         -- Each run of the simplifier can take a different
 175                         -- set of simplifier-specific flags.
 176   | CoreDoFloatInwards
 177   | CoreDoFloatOutwards Bool    -- True <=> float lambdas to top level
 178   | CoreLiberateCase
 179   | CoreDoPrintCore
 180   | CoreDoStaticArgs
 181   | CoreDoStrictness
 182   | CoreDoWorkerWrapper
 183   | CoreDoSpecialising
 184   | CoreDoUSPInf
 185   | CoreDoCPResult
 186   | CoreDoGlomBinds
 187   | CoreCSE
 188
 189   | CoreDoNothing        -- useful when building up lists of these things
 190 \end{code}
 191
 192 \begin{code}
 193 data StgToDo
 194   = StgDoStaticArgs
 195   | StgDoLambdaLift
 196   | StgDoMassageForProfiling  -- should be (next to) last
 197   -- There's also setStgVarInfo, but its absolute "lastness"
 198   -- is so critical that it is hardwired in (no flag).
 199   | D_stg_stats
 200 \end{code}
 201
 202 \begin{code}
 203 data SimplifierSwitch
 204   = MaxSimplifierIterations Int
 205   | SimplInlinePhase Int
 206   | DontApplyRules
 207   | NoCaseOfCase
 208   | SimplLetToCase
 209 \end{code}
 210
 211 %************************************************************************
 212 %*                                                                      *
 213 \subsection{Dynamic command-line options}
 214 %*                                                                      *
 215 %************************************************************************
 216
 217 \begin{code}
 218 data DynFlag
 219
 220    -- debugging flags
 221    = Opt_D_dump_all
 222    | Opt_D_dump_most
 223    | Opt_D_dump_absC
 224    | Opt_D_dump_asm
 225    | Opt_D_dump_cpranal
 226    | Opt_D_dump_deriv
 227    | Opt_D_dump_ds
 228    | Opt_D_dump_flatC
 229    | Opt_D_dump_foreign
 230    | Opt_D_dump_inlinings
 231    | Opt_D_dump_occur_anal
 232    | Opt_D_dump_parsed
 233    | Opt_D_dump_realC
 234    | Opt_D_dump_rn
 235    | Opt_D_dump_simpl
 236    | Opt_D_dump_simpl_iterations
 237    | Opt_D_dump_spec
 238    | Opt_D_dump_stg
 239    | Opt_D_dump_stranal
 240    | Opt_D_dump_tc
 241    | Opt_D_dump_types
 242    | Opt_D_dump_rules
 243    | Opt_D_dump_usagesp
 244    | Opt_D_dump_cse
 245    | Opt_D_dump_worker_wrapper
 246    | Opt_D_show_passes
 247    | Opt_D_dump_rn_trace
 248    | Opt_D_dump_rn_stats
 249    | Opt_D_dump_stix
 250    | Opt_D_dump_simpl_stats
 251    | Opt_D_source_stats
 252    | Opt_D_verbose_core2core
 253    | Opt_D_verbose_stg2stg
 254    | Opt_D_dump_hi_diffs
 255    | Opt_D_dump_minimal_imports
 256    | Opt_DoCoreLinting
 257    | Opt_DoStgLinting
 258    | Opt_DoUSPLinting
 259
 260    | Opt_WarnDuplicateExports
 261    | Opt_WarnHiShadows
 262    | Opt_WarnIncompletePatterns
 263    | Opt_WarnMissingFields
 264    | Opt_WarnMissingMethods
 265    | Opt_WarnMissingSigs
 266    | Opt_WarnNameShadowing
 267    | Opt_WarnOverlappingPatterns
 268    | Opt_WarnSimplePatterns
 269    | Opt_WarnTypeDefaults
 270    | Opt_WarnUnusedBinds
 271    | Opt_WarnUnusedImports
 272    | Opt_WarnUnusedMatches
 273    | Opt_WarnDeprecations
 274
 275    -- language opts
 276    | Opt_AllowOverlappingInstances
 277    | Opt_AllowUndecidableInstances
 278    | Opt_GlasgowExts
 279    deriving (Eq)
 280
 281 data DynFlags = DynFlags {
 282   coreToDo :: CoreToDo,
 283   stgToDo  :: StgToDo,
 284   hscLang  :: HscLang,
 285   flags    :: [DynFlag]
 286  }
 287
 288 dopt :: DynFlag -> DynFlags -> Bool
 289 dopt f dflags  = f `elem` (flags dflags)
 290
 291 dopt_CoreToDo :: DynFlags -> CoreToDo
 292 dopt_CoreToDo = coreToDo
 293
 294 dopt_StgToDo :: DynFlags -> StgToDo
 295 dopt_StgToDo = stgToDo
 296
 297 data HscLang
 298   = HscC
 299   | HscAsm
 300   | HscJava
 301   | HscInterpreter
 302   deriving Eq
 303
 304 dopt_HscLang :: DynFlags -> HscLang
 305 dopt_HscLang = hscLang
 306 \end{code}
 307
 308 %************************************************************************
 309 %*                                                                      *
 310 \subsection{Classifying command-line options}
 311 %*                                                                      *
 312 %************************************************************************
 313
 314 \begin{code}
 315 lookUp           :: FAST_STRING -> Bool
 316 lookup_int       :: String -> Maybe Int
 317 lookup_def_int   :: String -> Int -> Int
 318 lookup_def_float :: String -> Float -> Float
 319 lookup_str       :: String -> Maybe String
 320
 321 lookUp     sw = sw `elem` argv
 322
 323 lookup_str sw = firstJust (map (startsWith sw) unpacked_opts)
 324
 325 lookup_int sw = case (lookup_str sw) of
 326                   Nothing -> Nothing
 327                   Just xx -> Just (read xx)
 328
 329 lookup_def_int sw def = case (lookup_str sw) of
 330                             Nothing -> def              -- Use default
 331                             Just xx -> read xx
 332
 333 lookup_def_char sw def = case (lookup_str sw) of
 334                             Just (xx:_) -> xx
 335                             _           -> def          -- Use default
 336
 337 lookup_def_float sw def = case (lookup_str sw) of
 338                             Nothing -> def              -- Use default
 339                             Just xx -> read xx
 340
 341 unpacked_opts = map _UNPK_ argv
 342
 343 {-
 344  Putting the compiler options into temporary at-files
 345  may turn out to be necessary later on if we turn hsc into
 346  a pure Win32 application where I think there's a command-line
 347  length limit of 255. unpacked_opts understands the @ option.
 348
 349 unpacked_opts :: [String]
 350 unpacked_opts =
 351   concat $
 352   map (expandAts) $
 353   map _UNPK_ argv
 354   where
 355    expandAts ('@':fname) = words (unsafePerformIO (readFile fname))
 356    expandAts l = [l]
 357 -}
 358 \end{code}
 359
 360 %************************************************************************
 361 %*                                                                      *
 362 \subsection{Static options}
 363 %*                                                                      *
 364 %************************************************************************
 365
 366 \begin{code}
 367 -- debugging opts
 368 opt_PprStyle_NoPrags            = lookUp  SLIT("-dppr-noprags")
 369 opt_PprStyle_Debug              = lookUp  SLIT("-dppr-debug")
 370 opt_PprUserLength               = lookup_def_int "-dppr-user-length" 5 --ToDo: give this a name
 371
 372 -- profiling opts
 373 opt_AutoSccsOnAllToplevs        = lookUp  SLIT("-fauto-sccs-on-all-toplevs")
 374 opt_AutoSccsOnExportedToplevs   = lookUp  SLIT("-fauto-sccs-on-exported-toplevs")
 375 opt_AutoSccsOnIndividualCafs    = lookUp  SLIT("-fauto-sccs-on-individual-cafs")
 376 opt_AutoSccsOnDicts             = lookUp  SLIT("-fauto-sccs-on-dicts")
 377 opt_SccProfilingOn              = lookUp  SLIT("-fscc-profiling")
 378 opt_DoTickyProfiling            = lookUp  SLIT("-fticky-ticky")
 379
 380 -- language opts
 381 opt_AllStrict                   = lookUp  SLIT("-fall-strict")
 382 opt_DictsStrict                 = lookUp  SLIT("-fdicts-strict")
 383 opt_Generics                    = lookUp  SLIT("-fgenerics")
 384 opt_IrrefutableTuples           = lookUp  SLIT("-firrefutable-tuples")
 385 opt_MaxContextReductionDepth    = lookup_def_int "-fcontext-stack" mAX_CONTEXT_REDUCTION_DEPTH
 386 opt_NumbersStrict               = lookUp  SLIT("-fnumbers-strict")
 387 opt_Parallel                    = lookUp  SLIT("-fparallel")
 388 opt_SMP                         = lookUp  SLIT("-fsmp")
 389
 390 -- optimisation opts
 391 opt_DoSemiTagging               = lookUp  SLIT("-fsemi-tagging")
 392 opt_FoldrBuildOn                = lookUp  SLIT("-ffoldr-build-on")
 393 opt_LiberateCaseThreshold       = lookup_def_int "-fliberate-case-threshold" (10::Int)
 394 opt_StgDoLetNoEscapes           = lookUp  SLIT("-flet-no-escape")
 395 opt_UnfoldCasms                 = lookUp SLIT("-funfold-casms-in-hi-file")
 396 opt_UsageSPOn                   = lookUp  SLIT("-fusagesp-on")
 397 opt_UnboxStrictFields           = lookUp  SLIT("-funbox-strict-fields")
 398
 399 {-
 400    The optional '-inpackage=P' flag tells what package
 401    we are compiling this module for.
 402    The Prelude, for example is compiled with '-package prelude'
 403 -}
 404 opt_InPackage                   = case lookup_str "-inpackage=" of
 405                                     Just p  -> _PK_ p
 406                                     Nothing -> SLIT("Main")     -- The package name if none is specified
 407
 408 opt_EmitCExternDecls            = lookUp  SLIT("-femit-extern-decls")
 409 opt_EnsureSplittableC           = lookUp  SLIT("-fglobalise-toplev-names")
 410 opt_GranMacros                  = lookUp  SLIT("-fgransim")
 411 opt_HiVersion                   = lookup_def_int "-fhi-version=" 0 -- what version we're compiling.
 412 opt_HistorySize                 = lookup_def_int "-fhistory-size" 20
 413 opt_IgnoreAsserts               = lookUp  SLIT("-fignore-asserts")
 414 opt_IgnoreIfacePragmas          = lookUp  SLIT("-fignore-interface-pragmas")
 415 opt_NoHiCheck                   = lookUp  SLIT("-fno-hi-version-check")
 416 opt_NoImplicitPrelude           = lookUp  SLIT("-fno-implicit-prelude")
 417 opt_OmitBlackHoling             = lookUp  SLIT("-dno-black-holing")
 418 opt_OmitInterfacePragmas        = lookUp  SLIT("-fomit-interface-pragmas")
 419
 420 -- Simplifier switches
 421 opt_SimplNoPreInlining          = lookUp SLIT("-fno-pre-inlining")
 422         -- NoPreInlining is there just to see how bad things
 423         -- get if you don't do it!
 424 opt_SimplDoEtaReduction         = lookUp SLIT("-fdo-eta-reduction")
 425 opt_SimplDoLambdaEtaExpansion   = lookUp SLIT("-fdo-lambda-eta-expansion")
 426 opt_SimplCaseOfCase             = lookUp SLIT("-fcase-of-case")
 427 opt_SimplCaseMerge              = lookUp SLIT("-fcase-merge")
 428 opt_SimplPedanticBottoms        = lookUp SLIT("-fpedantic-bottoms")
 429 opt_SimplExcessPrecision        = lookUp SLIT("-fexcess-precision")
 430
 431 -- Unfolding control
 432 opt_UF_HiFileThreshold          = lookup_def_int "-funfolding-interface-threshold" (45::Int)
 433 opt_UF_CreationThreshold        = lookup_def_int "-funfolding-creation-threshold"  (45::Int)
 434 opt_UF_UseThreshold             = lookup_def_int "-funfolding-use-threshold"       (8::Int)     -- Discounts can be big
 435 opt_UF_FunAppDiscount           = lookup_def_int "-funfolding-fun-discount"        (6::Int)     -- It's great to inline a fn
 436 opt_UF_KeenessFactor            = lookup_def_float "-funfolding-keeness-factor"    (1.5::Float)
 437 opt_UF_UpdateInPlace            = lookUp  SLIT("-funfolding-update-in-place")
 438
 439 opt_UF_CheapOp  = ( 1 :: Int)   -- Only one instruction; and the args are charged for
 440 opt_UF_DearOp   = ( 4 :: Int)
 441
 442 opt_ReportCompile               = lookUp SLIT("-freport-compile")
 443 opt_NoPruneDecls                = lookUp SLIT("-fno-prune-decls")
 444 opt_NoPruneTyDecls              = lookUp SLIT("-fno-prune-tydecls")
 445 opt_Static                      = lookUp SLIT("-static")
 446 opt_Unregisterised              = lookUp SLIT("-funregisterised")
 447 opt_Verbose                     = lookUp SLIT("-v")
 448
 449 opt_UseVanillaRegs | opt_Unregisterised = 0
 450                    | otherwise          = mAX_Real_Vanilla_REG
 451 opt_UseFloatRegs   | opt_Unregisterised = 0
 452                    | otherwise          = mAX_Real_Float_REG
 453 opt_UseDoubleRegs  | opt_Unregisterised = 0
 454                    | otherwise          = mAX_Real_Double_REG
 455 opt_UseLongRegs    | opt_Unregisterised = 0
 456                    | otherwise          = mAX_Real_Long_REG
 457 \end{code}
 458
 459 %************************************************************************
 460 %*                                                                      *
 461 \subsection{List of static hsc flags}
 462 %*                                                                      *
 463 %************************************************************************
 464
 465 \begin{code}
 466 isStaticHscFlag f =
 467   f `elem` [
 468         "-fauto-sccs-on-all-toplevs",
 469         "-fauto-sccs-on-exported-toplevs",
 470         "-fauto-sccs-on-individual-cafs",
 471         "-fauto-sccs-on-dicts",
 472         "-fscc-profiling",
 473         "-fticky-ticky",
 474         "-fall-strict",
 475         "-fdicts-strict",
 476         "-fgenerics",
 477         "-firrefutable-tuples",
 478         "-fnumbers-strict",
 479         "-fparallel",
 480         "-fsmp",
 481         "-fsemi-tagging",
 482         "-ffoldr-build-on",
 483         "-flet-no-escape",
 484         "-funfold-casms-in-hi-file",
 485         "-fusagesp-on",
 486         "-funbox-strict-fields",
 487         "-femit-extern-decls",
 488         "-fglobalise-toplev-names",
 489         "-fgransim",
 490         "-fignore-asserts",
 491         "-fignore-interface-pragmas",
 492         "-fno-hi-version-check",
 493         "-fno-implicit-prelude",
 494         "-dno-black-holing",
 495         "-fomit-interface-pragmas",
 496         "-fno-pre-inlining",
 497         "-fdo-eta-reduction",
 498         "-fdo-lambda-eta-expansion",
 499         "-fcase-of-case",
 500         "-fcase-merge",
 501         "-fpedantic-bottoms",
 502         "-fexcess-precision",
 503         "-funfolding-update-in-place",
 504         "-freport-compile",
 505         "-fno-prune-decls",
 506         "-fno-prune-tydecls",
 507         "-static",
 508         "-funregisterised",
 509         "-v" ]
 510   || any (flip prefixMatch f) [
 511         "-fcontext-stack",
 512         "-fliberate-case-threshold",
 513         "-fhi-version=",
 514         "-fhistory-size",
 515         "-funfolding-interface-threshold",
 516         "-funfolding-creation-threshold",
 517         "-funfolding-use-threshold",
 518         "-funfolding-fun-discount",
 519         "-funfolding-keeness-factor"
 520      ]
 521 \end{code}
 522
 523 %************************************************************************
 524 %*                                                                      *
 525 \subsection{Switch ordering}
 526 %*                                                                      *
 527 %************************************************************************
 528
 529 These things behave just like enumeration types.
 530
 531 \begin{code}
 532 instance Eq SimplifierSwitch where
 533     a == b = tagOf_SimplSwitch a ==# tagOf_SimplSwitch b
 534
 535 instance Ord SimplifierSwitch where
 536     a <  b  = tagOf_SimplSwitch a <# tagOf_SimplSwitch b
 537     a <= b  = tagOf_SimplSwitch a <=# tagOf_SimplSwitch b
 538
 539
 540 tagOf_SimplSwitch (SimplInlinePhase _)          = _ILIT(1)
 541 tagOf_SimplSwitch (MaxSimplifierIterations _)   = _ILIT(2)
 542 tagOf_SimplSwitch DontApplyRules                = _ILIT(3)
 543 tagOf_SimplSwitch SimplLetToCase                = _ILIT(4)
 544 tagOf_SimplSwitch NoCaseOfCase                  = _ILIT(5)
 545
 546 -- If you add anything here, be sure to change lAST_SIMPL_SWITCH_TAG, too!
 547
 548 lAST_SIMPL_SWITCH_TAG = 5
 549 \end{code}
 550
 551 %************************************************************************
 552 %*                                                                      *
 553 \subsection{Switch lookup}
 554 %*                                                                      *
 555 %************************************************************************
 556
 557 \begin{code}
 558 isAmongSimpl :: [SimplifierSwitch] -> SimplifierSwitch -> SwitchResult
 559 isAmongSimpl on_switches                -- Switches mentioned later occur *earlier*
 560                                         -- in the list; defaults right at the end.
 561   = let
 562         tidied_on_switches = foldl rm_dups [] on_switches
 563                 -- The fold*l* ensures that we keep the latest switches;
 564                 -- ie the ones that occur earliest in the list.
 565
 566         sw_tbl :: Array Int SwitchResult
 567         sw_tbl = (array (0, lAST_SIMPL_SWITCH_TAG) -- bounds...
 568                         all_undefined)
 569                  // defined_elems
 570
 571         all_undefined = [ (i, SwBool False) | i <- [0 .. lAST_SIMPL_SWITCH_TAG ] ]
 572
 573         defined_elems = map mk_assoc_elem tidied_on_switches
 574     in
 575     -- (avoid some unboxing, bounds checking, and other horrible things:)
 576 #if __GLASGOW_HASKELL__ < 405
 577     case sw_tbl of { Array bounds_who_needs_'em stuff ->
 578 #else
 579     case sw_tbl of { Array _ _ stuff ->
 580 #endif
 581     \ switch ->
 582         case (indexArray# stuff (tagOf_SimplSwitch switch)) of
 583 #if __GLASGOW_HASKELL__ < 400
 584           Lift v -> v
 585 #elif __GLASGOW_HASKELL__ < 403
 586           (# _, v #) -> v
 587 #else
 588           (# v #) -> v
 589 #endif
 590     }
 591   where
 592     mk_assoc_elem k@(MaxSimplifierIterations lvl)
 593         = (iBox (tagOf_SimplSwitch k), SwInt lvl)
 594     mk_assoc_elem k@(SimplInlinePhase n)
 595         = (iBox (tagOf_SimplSwitch k), SwInt n)
 596     mk_assoc_elem k
 597         = (iBox (tagOf_SimplSwitch k), SwBool True) -- I'm here, Mom!
 598
 599     -- cannot have duplicates if we are going to use the array thing
 600     rm_dups switches_so_far switch
 601       = if switch `is_elem` switches_so_far
 602         then switches_so_far
 603         else switch : switches_so_far
 604       where
 605         sw `is_elem` []     = False
 606         sw `is_elem` (s:ss) = (tagOf_SimplSwitch sw) ==# (tagOf_SimplSwitch s)
 607                             || sw `is_elem` ss
 608 \end{code}
 609
 610 Default settings for simplifier switches
 611
 612 \begin{code}
 613 defaultSimplSwitches = [MaxSimplifierIterations 1]
 614 \end{code}
 615
 616 %************************************************************************
 617 %*                                                                      *
 618 \subsection{Misc functions for command-line options}
 619 %*                                                                      *
 620 %************************************************************************
 621
 622
 623 \begin{code}
 624 switchIsOn :: (switch -> SwitchResult) -> switch -> Bool
 625
 626 switchIsOn lookup_fn switch
 627   = case (lookup_fn switch) of
 628       SwBool False -> False
 629       _            -> True
 630
 631 intSwitchSet :: (switch -> SwitchResult)
 632              -> (Int -> switch)
 633              -> Maybe Int
 634
 635 intSwitchSet lookup_fn switch
 636   = case (lookup_fn (switch (panic "intSwitchSet"))) of
 637       SwInt int -> Just int
 638       _         -> Nothing
 639 \end{code}
 640
 641 \begin{code}
 642 startsWith :: String -> String -> Maybe String
 643 -- startsWith pfx (pfx++rest) = Just rest
 644
 645 startsWith []     str = Just str
 646 startsWith (c:cs) (s:ss)
 647   = if c /= s then Nothing else startsWith cs ss
 648 startsWith  _     []  = Nothing
 649
 650 endsWith  :: String -> String -> Maybe String
 651 endsWith cs ss
 652   = case (startsWith (reverse cs) (reverse ss)) of
 653       Nothing -> Nothing
 654       Just rs -> Just (reverse rs)
 655 \end{code}