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
  14         HscLang(..),
  15         DynFlag(..),    -- needed non-abstractly by DriverFlags
  16         DynFlags(..),
  17         defaultDynFlags,
  18
  19         v_Static_hsc_opts,
  20
  21         intSwitchSet,
  22         switchIsOn,
  23         isStaticHscFlag,
  24
  25         opt_PprStyle_NoPrags,
  26         opt_PprStyle_RawTypes,
  27         opt_PprUserLength,
  28         opt_PprStyle_Debug,
  29
  30         dopt,
  31
  32         -- other dynamic flags
  33         dopt_CoreToDo,
  34         dopt_StgToDo,
  35         dopt_HscLang,
  36         dopt_OutName,
  37
  38         -- profiling opts
  39         opt_AutoSccsOnAllToplevs,
  40         opt_AutoSccsOnExportedToplevs,
  41         opt_AutoSccsOnIndividualCafs,
  42         opt_AutoSccsOnDicts,
  43         opt_SccProfilingOn,
  44         opt_DoTickyProfiling,
  45
  46         -- language opts
  47         opt_AllStrict,
  48         opt_DictsStrict,
  49         opt_MaxContextReductionDepth,
  50         opt_IrrefutableTuples,
  51         opt_NumbersStrict,
  52         opt_Parallel,
  53         opt_SMP,
  54         opt_NoMonomorphismRestriction,
  55
  56         -- optimisation opts
  57         opt_NoMethodSharing,
  58         opt_DoSemiTagging,
  59         opt_FoldrBuildOn,
  60         opt_LiberateCaseThreshold,
  61         opt_StgDoLetNoEscapes,
  62         opt_UnfoldCasms,
  63         opt_UsageSPOn,
  64         opt_UnboxStrictFields,
  65         opt_SimplNoPreInlining,
  66         opt_SimplDoEtaReduction,
  67         opt_SimplDoLambdaEtaExpansion,
  68         opt_SimplCaseOfCase,
  69         opt_SimplCaseMerge,
  70         opt_SimplPedanticBottoms,
  71         opt_SimplExcessPrecision,
  72
  73         -- Unfolding control
  74         opt_UF_HiFileThreshold,
  75         opt_UF_CreationThreshold,
  76         opt_UF_UseThreshold,
  77         opt_UF_FunAppDiscount,
  78         opt_UF_KeenessFactor,
  79         opt_UF_UpdateInPlace,
  80         opt_UF_CheapOp,
  81         opt_UF_DearOp,
  82
  83         -- misc opts
  84         opt_InPackage,
  85         opt_EmitCExternDecls,
  86         opt_EnsureSplittableC,
  87         opt_GranMacros,
  88         opt_HiVersion,
  89         opt_HistorySize,
  90         opt_IgnoreAsserts,
  91         opt_IgnoreIfacePragmas,
  92         opt_NoHiCheck,
  93         opt_OmitBlackHoling,
  94         opt_OmitInterfacePragmas,
  95         opt_NoPruneTyDecls,
  96         opt_NoPruneDecls,
  97         opt_Static,
  98         opt_Unregisterised
  99     ) where
 100
 101 #include "HsVersions.h"
 102
 103 import Array    ( array, (//) )
 104 import GlaExts
 105 import IOExts   ( IORef, readIORef )
 106 import Constants        -- Default values for some flags
 107 import Util
 108 import FastTypes
 109 import Config
 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   = StgDoMassageForProfiling  -- should be (next to) last
 195   -- There's also setStgVarInfo, but its absolute "lastness"
 196   -- is so critical that it is hardwired in (no flag).
 197   | D_stg_stats
 198 \end{code}
 199
 200 \begin{code}
 201 data SimplifierSwitch
 202   = MaxSimplifierIterations Int
 203   | SimplInlinePhase Int
 204   | DontApplyRules
 205   | NoCaseOfCase
 206   | SimplLetToCase
 207 \end{code}
 208
 209 %************************************************************************
 210 %*                                                                      *
 211 \subsection{Dynamic command-line options}
 212 %*                                                                      *
 213 %************************************************************************
 214
 215 \begin{code}
 216 data DynFlag
 217
 218    -- debugging flags
 219    = Opt_D_dump_absC
 220    | Opt_D_dump_asm
 221    | Opt_D_dump_cpranal
 222    | Opt_D_dump_deriv
 223    | Opt_D_dump_ds
 224    | Opt_D_dump_flatC
 225    | Opt_D_dump_foreign
 226    | Opt_D_dump_inlinings
 227    | Opt_D_dump_occur_anal
 228    | Opt_D_dump_parsed
 229    | Opt_D_dump_realC
 230    | Opt_D_dump_rn
 231    | Opt_D_dump_simpl
 232    | Opt_D_dump_simpl_iterations
 233    | Opt_D_dump_spec
 234    | Opt_D_dump_sat
 235    | Opt_D_dump_stg
 236    | Opt_D_dump_stranal
 237    | Opt_D_dump_tc
 238    | Opt_D_dump_types
 239    | Opt_D_dump_rules
 240    | Opt_D_dump_usagesp
 241    | Opt_D_dump_cse
 242    | Opt_D_dump_worker_wrapper
 243    | Opt_D_dump_rn_trace
 244    | Opt_D_dump_rn_stats
 245    | Opt_D_dump_stix
 246    | Opt_D_dump_simpl_stats
 247    | Opt_D_dump_BCOs
 248    | Opt_D_source_stats
 249    | Opt_D_verbose_core2core
 250    | Opt_D_verbose_stg2stg
 251    | Opt_D_dump_hi
 252    | Opt_D_dump_hi_diffs
 253    | Opt_D_dump_minimal_imports
 254    | Opt_DoCoreLinting
 255    | Opt_DoStgLinting
 256    | Opt_DoUSPLinting
 257
 258    | Opt_WarnDuplicateExports
 259    | Opt_WarnHiShadows
 260    | Opt_WarnIncompletePatterns
 261    | Opt_WarnMissingFields
 262    | Opt_WarnMissingMethods
 263    | Opt_WarnMissingSigs
 264    | Opt_WarnNameShadowing
 265    | Opt_WarnOverlappingPatterns
 266    | Opt_WarnSimplePatterns
 267    | Opt_WarnTypeDefaults
 268    | Opt_WarnUnusedBinds
 269    | Opt_WarnUnusedImports
 270    | Opt_WarnUnusedMatches
 271    | Opt_WarnDeprecations
 272
 273    -- language opts
 274    | Opt_AllowOverlappingInstances
 275    | Opt_AllowUndecidableInstances
 276    | Opt_GlasgowExts
 277    | Opt_Generics
 278    | Opt_NoImplicitPrelude
 279
 280    -- misc
 281    | Opt_ReportCompile
 282    deriving (Eq)
 283
 284 data DynFlags = DynFlags {
 285   coreToDo              :: [CoreToDo],
 286   stgToDo               :: [StgToDo],
 287   hscLang               :: HscLang,
 288   hscOutName            :: String,      -- name of the output file
 289   verbosity             :: Int,         -- verbosity level
 290   cppFlag               :: Bool,        -- preprocess with cpp?
 291   stolen_x86_regs       :: Int,
 292   cmdlineHcIncludes     :: [String],    -- -#includes
 293
 294   -- options for particular phases
 295   opt_L                 :: [String],
 296   opt_P                 :: [String],
 297   opt_c                 :: [String],
 298   opt_a                 :: [String],
 299   opt_m                 :: [String],
 300
 301   -- hsc dynamic flags
 302   flags                 :: [DynFlag]
 303  }
 304
 305 defaultDynFlags = DynFlags {
 306   coreToDo = [], stgToDo = [],
 307   hscLang = HscC,
 308   hscOutName = "",
 309   verbosity = 0,
 310   cppFlag               = False,
 311   stolen_x86_regs       = 4,
 312   cmdlineHcIncludes     = [],
 313   opt_L                 = [],
 314   opt_P                 = [],
 315   opt_c                 = [],
 316   opt_a                 = [],
 317   opt_m                 = [],
 318   flags = []
 319   }
 320
 321 {-
 322     Verbosity levels:
 323
 324     0   |   print errors & warnings only
 325     1   |   minimal verbosity: print "compiling M ... done." for each module.
 326     2   |   equivalent to -dshow-passes
 327     3   |   equivalent to existing "ghc -v"
 328     4   |   "ghc -v -ddump-most"
 329     5   |   "ghc -v -ddump-all"
 330 -}
 331
 332 dopt :: DynFlag -> DynFlags -> Bool
 333 dopt f dflags  = f `elem` (flags dflags)
 334
 335 dopt_CoreToDo :: DynFlags -> [CoreToDo]
 336 dopt_CoreToDo = coreToDo
 337
 338 dopt_StgToDo :: DynFlags -> [StgToDo]
 339 dopt_StgToDo = stgToDo
 340
 341 dopt_OutName :: DynFlags -> String
 342 dopt_OutName = hscOutName
 343
 344 data HscLang
 345   = HscC
 346   | HscAsm
 347   | HscJava
 348   | HscInterpreted
 349     deriving (Eq, Show)
 350
 351 dopt_HscLang :: DynFlags -> HscLang
 352 dopt_HscLang = hscLang
 353 \end{code}
 354
 355 %************************************************************************
 356 %*                                                                      *
 357 \subsection{Classifying command-line options}
 358 %*                                                                      *
 359 %************************************************************************
 360
 361 \begin{code}
 362 -- v_Statis_hsc_opts is here to avoid a circular dependency with
 363 -- main/DriverState.
 364 GLOBAL_VAR(v_Static_hsc_opts, [], [String])
 365
 366 lookUp           :: FAST_STRING -> Bool
 367 lookup_int       :: String -> Maybe Int
 368 lookup_def_int   :: String -> Int -> Int
 369 lookup_def_float :: String -> Float -> Float
 370 lookup_str       :: String -> Maybe String
 371
 372 unpacked_static_opts = unsafePerformIO (readIORef v_Static_hsc_opts)
 373 packed_static_opts   = map _PK_ unpacked_static_opts
 374
 375 lookUp     sw = sw `elem` packed_static_opts
 376
 377 lookup_str sw = firstJust (map (startsWith sw) unpacked_static_opts)
 378
 379 lookup_int sw = case (lookup_str sw) of
 380                   Nothing -> Nothing
 381                   Just xx -> Just (read xx)
 382
 383 lookup_def_int sw def = case (lookup_str sw) of
 384                             Nothing -> def              -- Use default
 385                             Just xx -> read xx
 386
 387 lookup_def_float sw def = case (lookup_str sw) of
 388                             Nothing -> def              -- Use default
 389                             Just xx -> read xx
 390
 391
 392 {-
 393  Putting the compiler options into temporary at-files
 394  may turn out to be necessary later on if we turn hsc into
 395  a pure Win32 application where I think there's a command-line
 396  length limit of 255. unpacked_opts understands the @ option.
 397
 398 unpacked_opts :: [String]
 399 unpacked_opts =
 400   concat $
 401   map (expandAts) $
 402   map _UNPK_ argv  -- NOT ARGV any more: v_Static_hsc_opts
 403   where
 404    expandAts ('@':fname) = words (unsafePerformIO (readFile fname))
 405    expandAts l = [l]
 406 -}
 407 \end{code}
 408
 409 %************************************************************************
 410 %*                                                                      *
 411 \subsection{Static options}
 412 %*                                                                      *
 413 %************************************************************************
 414
 415 \begin{code}
 416 -- debugging opts
 417 opt_PprStyle_NoPrags            = lookUp  SLIT("-dppr-noprags")
 418 opt_PprStyle_Debug              = lookUp  SLIT("-dppr-debug")
 419 opt_PprStyle_RawTypes           = lookUp  SLIT("-dppr-rawtypes")
 420 opt_PprUserLength               = lookup_def_int "-dppr-user-length" 5 --ToDo: give this a name
 421
 422 -- profiling opts
 423 opt_AutoSccsOnAllToplevs        = lookUp  SLIT("-fauto-sccs-on-all-toplevs")
 424 opt_AutoSccsOnExportedToplevs   = lookUp  SLIT("-fauto-sccs-on-exported-toplevs")
 425 opt_AutoSccsOnIndividualCafs    = lookUp  SLIT("-fauto-sccs-on-individual-cafs")
 426 opt_AutoSccsOnDicts             = lookUp  SLIT("-fauto-sccs-on-dicts")
 427 opt_SccProfilingOn              = lookUp  SLIT("-fscc-profiling")
 428 opt_DoTickyProfiling            = lookUp  SLIT("-fticky-ticky")
 429
 430 -- language opts
 431 opt_AllStrict                   = lookUp  SLIT("-fall-strict")
 432 opt_NoMonomorphismRestriction   = lookUp  SLIT("-fno-monomorphism-restriction")
 433 opt_DictsStrict                 = lookUp  SLIT("-fdicts-strict")
 434 opt_IrrefutableTuples           = lookUp  SLIT("-firrefutable-tuples")
 435 opt_MaxContextReductionDepth    = lookup_def_int "-fcontext-stack" mAX_CONTEXT_REDUCTION_DEPTH
 436 opt_NumbersStrict               = lookUp  SLIT("-fnumbers-strict")
 437 opt_Parallel                    = lookUp  SLIT("-fparallel")
 438 opt_SMP                         = lookUp  SLIT("-fsmp")
 439
 440 -- optimisation opts
 441 opt_NoMethodSharing             = lookUp  SLIT("-fno-method-sharing")
 442 opt_DoSemiTagging               = lookUp  SLIT("-fsemi-tagging")
 443 opt_FoldrBuildOn                = lookUp  SLIT("-ffoldr-build-on")
 444 opt_LiberateCaseThreshold       = lookup_def_int "-fliberate-case-threshold" (10::Int)
 445 opt_StgDoLetNoEscapes           = lookUp  SLIT("-flet-no-escape")
 446 opt_UnfoldCasms                 = lookUp SLIT("-funfold-casms-in-hi-file")
 447 opt_UsageSPOn                   = lookUp  SLIT("-fusagesp-on")
 448 opt_UnboxStrictFields           = lookUp  SLIT("-funbox-strict-fields")
 449
 450 {-
 451    The optional '-inpackage=P' flag tells what package
 452    we are compiling this module for.
 453    The Prelude, for example is compiled with '-package prelude'
 454 -}
 455 opt_InPackage                   = case lookup_str "-inpackage=" of
 456                                     Just p  -> _PK_ p
 457                                     Nothing -> SLIT("Main")     -- The package name if none is specified
 458
 459 opt_EmitCExternDecls            = lookUp  SLIT("-femit-extern-decls")
 460 opt_EnsureSplittableC           = lookUp  SLIT("-fglobalise-toplev-names")
 461 opt_GranMacros                  = lookUp  SLIT("-fgransim")
 462 opt_HiVersion                   = read cProjectVersionInt :: Int
 463 opt_HistorySize                 = lookup_def_int "-fhistory-size" 20
 464 opt_IgnoreAsserts               = lookUp  SLIT("-fignore-asserts")
 465 opt_IgnoreIfacePragmas          = lookUp  SLIT("-fignore-interface-pragmas")
 466 opt_NoHiCheck                   = lookUp  SLIT("-fno-hi-version-check")
 467 opt_OmitBlackHoling             = lookUp  SLIT("-dno-black-holing")
 468 opt_OmitInterfacePragmas        = lookUp  SLIT("-fomit-interface-pragmas")
 469
 470 -- Simplifier switches
 471 opt_SimplNoPreInlining          = lookUp SLIT("-fno-pre-inlining")
 472         -- NoPreInlining is there just to see how bad things
 473         -- get if you don't do it!
 474 opt_SimplDoEtaReduction         = lookUp SLIT("-fdo-eta-reduction")
 475 opt_SimplDoLambdaEtaExpansion   = lookUp SLIT("-fdo-lambda-eta-expansion")
 476 opt_SimplCaseOfCase             = lookUp SLIT("-fcase-of-case")
 477 opt_SimplCaseMerge              = lookUp SLIT("-fcase-merge")
 478 opt_SimplPedanticBottoms        = lookUp SLIT("-fpedantic-bottoms")
 479 opt_SimplExcessPrecision        = lookUp SLIT("-fexcess-precision")
 480
 481 -- Unfolding control
 482 opt_UF_HiFileThreshold          = lookup_def_int "-funfolding-interface-threshold" (45::Int)
 483 opt_UF_CreationThreshold        = lookup_def_int "-funfolding-creation-threshold"  (45::Int)
 484 opt_UF_UseThreshold             = lookup_def_int "-funfolding-use-threshold"       (8::Int)     -- Discounts can be big
 485 opt_UF_FunAppDiscount           = lookup_def_int "-funfolding-fun-discount"        (6::Int)     -- It's great to inline a fn
 486 opt_UF_KeenessFactor            = lookup_def_float "-funfolding-keeness-factor"    (1.5::Float)
 487 opt_UF_UpdateInPlace            = lookUp  SLIT("-funfolding-update-in-place")
 488
 489 opt_UF_CheapOp  = ( 1 :: Int)   -- Only one instruction; and the args are charged for
 490 opt_UF_DearOp   = ( 4 :: Int)
 491
 492 opt_NoPruneDecls                = lookUp SLIT("-fno-prune-decls")
 493 opt_NoPruneTyDecls              = lookUp SLIT("-fno-prune-tydecls")
 494 opt_Static                      = lookUp SLIT("-static")
 495 opt_Unregisterised              = lookUp SLIT("-funregisterised")
 496 \end{code}
 497
 498 %************************************************************************
 499 %*                                                                      *
 500 \subsection{List of static hsc flags}
 501 %*                                                                      *
 502 %************************************************************************
 503
 504 \begin{code}
 505 isStaticHscFlag f =
 506   f `elem` [
 507         "fauto-sccs-on-all-toplevs",
 508         "fauto-sccs-on-exported-toplevs",
 509         "fauto-sccs-on-individual-cafs",
 510         "fauto-sccs-on-dicts",
 511         "fscc-profiling",
 512         "fticky-ticky",
 513         "fall-strict",
 514         "fdicts-strict",
 515         "firrefutable-tuples",
 516         "fnumbers-strict",
 517         "fparallel",
 518         "fsmp",
 519         "fsemi-tagging",
 520         "ffoldr-build-on",
 521         "flet-no-escape",
 522         "funfold-casms-in-hi-file",
 523         "fusagesp-on",
 524         "funbox-strict-fields",
 525         "femit-extern-decls",
 526         "fglobalise-toplev-names",
 527         "fgransim",
 528         "fignore-asserts",
 529         "fignore-interface-pragmas",
 530         "fno-hi-version-check",
 531         "dno-black-holing",
 532         "fomit-interface-pragmas",
 533         "fno-pre-inlining",
 534         "fdo-eta-reduction",
 535         "fdo-lambda-eta-expansion",
 536         "fcase-of-case",
 537         "fcase-merge",
 538         "fpedantic-bottoms",
 539         "fexcess-precision",
 540         "funfolding-update-in-place",
 541         "freport-compile",
 542         "fno-prune-decls",
 543         "fno-prune-tydecls",
 544         "static",
 545         "funregisterised"
 546         ]
 547   || any (flip prefixMatch f) [
 548         "fcontext-stack",
 549         "fliberate-case-threshold",
 550         "fhistory-size",
 551         "funfolding-interface-threshold",
 552         "funfolding-creation-threshold",
 553         "funfolding-use-threshold",
 554         "funfolding-fun-discount",
 555         "funfolding-keeness-factor"
 556      ]
 557 \end{code}
 558
 559 %************************************************************************
 560 %*                                                                      *
 561 \subsection{Switch ordering}
 562 %*                                                                      *
 563 %************************************************************************
 564
 565 These things behave just like enumeration types.
 566
 567 \begin{code}
 568 instance Eq SimplifierSwitch where
 569     a == b = tagOf_SimplSwitch a ==# tagOf_SimplSwitch b
 570
 571 instance Ord SimplifierSwitch where
 572     a <  b  = tagOf_SimplSwitch a <# tagOf_SimplSwitch b
 573     a <= b  = tagOf_SimplSwitch a <=# tagOf_SimplSwitch b
 574
 575
 576 tagOf_SimplSwitch (SimplInlinePhase _)          = _ILIT(1)
 577 tagOf_SimplSwitch (MaxSimplifierIterations _)   = _ILIT(2)
 578 tagOf_SimplSwitch DontApplyRules                = _ILIT(3)
 579 tagOf_SimplSwitch SimplLetToCase                = _ILIT(4)
 580 tagOf_SimplSwitch NoCaseOfCase                  = _ILIT(5)
 581
 582 -- If you add anything here, be sure to change lAST_SIMPL_SWITCH_TAG, too!
 583
 584 lAST_SIMPL_SWITCH_TAG = 5
 585 \end{code}
 586
 587 %************************************************************************
 588 %*                                                                      *
 589 \subsection{Switch lookup}
 590 %*                                                                      *
 591 %************************************************************************
 592
 593 \begin{code}
 594 isAmongSimpl :: [SimplifierSwitch] -> SimplifierSwitch -> SwitchResult
 595 isAmongSimpl on_switches                -- Switches mentioned later occur *earlier*
 596                                         -- in the list; defaults right at the end.
 597   = let
 598         tidied_on_switches = foldl rm_dups [] on_switches
 599                 -- The fold*l* ensures that we keep the latest switches;
 600                 -- ie the ones that occur earliest in the list.
 601
 602         sw_tbl :: Array Int SwitchResult
 603         sw_tbl = (array (0, lAST_SIMPL_SWITCH_TAG) -- bounds...
 604                         all_undefined)
 605                  // defined_elems
 606
 607         all_undefined = [ (i, SwBool False) | i <- [0 .. lAST_SIMPL_SWITCH_TAG ] ]
 608
 609         defined_elems = map mk_assoc_elem tidied_on_switches
 610     in
 611     -- (avoid some unboxing, bounds checking, and other horrible things:)
 612 #if __GLASGOW_HASKELL__ < 405
 613     case sw_tbl of { Array bounds_who_needs_'em stuff ->
 614 #else
 615     case sw_tbl of { Array _ _ stuff ->
 616 #endif
 617     \ switch ->
 618         case (indexArray# stuff (tagOf_SimplSwitch switch)) of
 619 #if __GLASGOW_HASKELL__ < 400
 620           Lift v -> v
 621 #elif __GLASGOW_HASKELL__ < 403
 622           (# _, v #) -> v
 623 #else
 624           (# v #) -> v
 625 #endif
 626     }
 627   where
 628     mk_assoc_elem k@(MaxSimplifierIterations lvl)
 629         = (iBox (tagOf_SimplSwitch k), SwInt lvl)
 630     mk_assoc_elem k@(SimplInlinePhase n)
 631         = (iBox (tagOf_SimplSwitch k), SwInt n)
 632     mk_assoc_elem k
 633         = (iBox (tagOf_SimplSwitch k), SwBool True) -- I'm here, Mom!
 634
 635     -- cannot have duplicates if we are going to use the array thing
 636     rm_dups switches_so_far switch
 637       = if switch `is_elem` switches_so_far
 638         then switches_so_far
 639         else switch : switches_so_far
 640       where
 641         sw `is_elem` []     = False
 642         sw `is_elem` (s:ss) = (tagOf_SimplSwitch sw) ==# (tagOf_SimplSwitch s)
 643                             || sw `is_elem` ss
 644 \end{code}
 645
 646
 647 %************************************************************************
 648 %*                                                                      *
 649 \subsection{Misc functions for command-line options}
 650 %*                                                                      *
 651 %************************************************************************
 652
 653
 654 \begin{code}
 655 switchIsOn :: (switch -> SwitchResult) -> switch -> Bool
 656
 657 switchIsOn lookup_fn switch
 658   = case (lookup_fn switch) of
 659       SwBool False -> False
 660       _            -> True
 661
 662 intSwitchSet :: (switch -> SwitchResult)
 663              -> (Int -> switch)
 664              -> Maybe Int
 665
 666 intSwitchSet lookup_fn switch
 667   = case (lookup_fn (switch (panic "intSwitchSet"))) of
 668       SwInt int -> Just int
 669       _         -> Nothing
 670 \end{code}
 671
 672 \begin{code}
 673 startsWith :: String -> String -> Maybe String
 674 -- startsWith pfx (pfx++rest) = Just rest
 675
 676 startsWith []     str = Just str
 677 startsWith (c:cs) (s:ss)
 678   = if c /= s then Nothing else startsWith cs ss
 679 startsWith  _     []  = Nothing
 680
 681 endsWith  :: String -> String -> Maybe String
 682 endsWith cs ss
 683   = case (startsWith (reverse cs) (reverse ss)) of
 684       Nothing -> Nothing
 685       Just rs -> Just (reverse rs)
 686 \end{code}