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         -- sets of warning opts
  39         standardWarnings,
  40         minusWOpts,
  41         minusWallOpts,
  42
  43         -- profiling opts
  44         opt_AutoSccsOnAllToplevs,
  45         opt_AutoSccsOnExportedToplevs,
  46         opt_AutoSccsOnIndividualCafs,
  47         opt_AutoSccsOnDicts,
  48         opt_SccProfilingOn,
  49         opt_DoTickyProfiling,
  50
  51         -- language opts
  52         opt_AllStrict,
  53         opt_DictsStrict,
  54         opt_MaxContextReductionDepth,
  55         opt_IrrefutableTuples,
  56         opt_NumbersStrict,
  57         opt_Parallel,
  58         opt_SMP,
  59         opt_NoMonomorphismRestriction,
  60         opt_KeepStgTypes,
  61
  62         -- optimisation opts
  63         opt_NoMethodSharing,
  64         opt_DoSemiTagging,
  65         opt_FoldrBuildOn,
  66         opt_LiberateCaseThreshold,
  67         opt_StgDoLetNoEscapes,
  68         opt_UnfoldCasms,
  69         opt_UsageSPOn,
  70         opt_UnboxStrictFields,
  71         opt_SimplNoPreInlining,
  72         opt_SimplDoEtaReduction,
  73         opt_SimplDoLambdaEtaExpansion,
  74         opt_SimplCaseMerge,
  75         opt_SimplExcessPrecision,
  76
  77         -- Unfolding control
  78         opt_UF_CreationThreshold,
  79         opt_UF_UseThreshold,
  80         opt_UF_FunAppDiscount,
  81         opt_UF_KeenessFactor,
  82         opt_UF_UpdateInPlace,
  83         opt_UF_CheapOp,
  84         opt_UF_DearOp,
  85
  86         -- misc opts
  87         opt_InPackage,
  88         opt_EmitCExternDecls,
  89         opt_EnsureSplittableC,
  90         opt_GranMacros,
  91         opt_HiVersion,
  92         opt_HistorySize,
  93         opt_IgnoreAsserts,
  94         opt_IgnoreIfacePragmas,
  95         opt_NoHiCheck,
  96         opt_OmitBlackHoling,
  97         opt_OmitInterfacePragmas,
  98         opt_NoPruneTyDecls,
  99         opt_NoPruneDecls,
 100         opt_Static,
 101         opt_Unregisterised
 102     ) where
 103
 104 #include "HsVersions.h"
 105
 106 import Array    ( array, (//) )
 107 import GlaExts
 108 import IOExts   ( IORef, readIORef )
 109 import Constants        -- Default values for some flags
 110 import Util
 111 import FastTypes
 112 import Config
 113
 114 import Maybes           ( firstJust )
 115 import Panic            ( panic )
 116
 117 #if __GLASGOW_HASKELL__ < 301
 118 import ArrBase  ( Array(..) )
 119 #else
 120 import PrelArr  ( Array(..) )
 121 #endif
 122 \end{code}
 123
 124 %************************************************************************
 125 %*                                                                      *
 126 \subsection{Command-line options}
 127 %*                                                                      *
 128 %************************************************************************
 129
 130 The hsc command-line options are split into two categories:
 131
 132   - static flags
 133   - dynamic flags
 134
 135 Static flags are represented by top-level values of type Bool or Int,
 136 for example.  They therefore have the same value throughout the
 137 invocation of hsc.
 138
 139 Dynamic flags are represented by an abstract type, DynFlags, which is
 140 passed into hsc by the compilation manager for every compilation.
 141 Dynamic flags are those that change on a per-compilation basis,
 142 perhaps because they may be present in the OPTIONS pragma at the top
 143 of a module.
 144
 145 Other flag-related blurb:
 146
 147 A list of {\em ToDo}s is things to be done in a particular part of
 148 processing.  A (fictitious) example for the Core-to-Core simplifier
 149 might be: run the simplifier, then run the strictness analyser, then
 150 run the simplifier again (three ``todos'').
 151
 152 There are three ``to-do processing centers'' at the moment.  In the
 153 main loop (\tr{main/Main.lhs}), in the Core-to-Core processing loop
 154 (\tr{simplCore/SimplCore.lhs), and in the STG-to-STG processing loop
 155 (\tr{simplStg/SimplStg.lhs}).
 156
 157 %************************************************************************
 158 %*                                                                      *
 159 \subsection{Datatypes associated with command-line options}
 160 %*                                                                      *
 161 %************************************************************************
 162
 163 \begin{code}
 164 data SwitchResult
 165   = SwBool      Bool            -- on/off
 166   | SwString    FAST_STRING     -- nothing or a String
 167   | SwInt       Int             -- nothing or an Int
 168 \end{code}
 169
 170 \begin{code}
 171 data CoreToDo           -- These are diff core-to-core passes,
 172                         -- which may be invoked in any order,
 173                         -- as many times as you like.
 174
 175   = CoreDoSimplify      -- The core-to-core simplifier.
 176         (SimplifierSwitch -> SwitchResult)
 177                         -- Each run of the simplifier can take a different
 178                         -- set of simplifier-specific flags.
 179   | CoreDoFloatInwards
 180   | CoreDoFloatOutwards Bool    -- True <=> float lambdas to top level
 181   | CoreLiberateCase
 182   | CoreDoPrintCore
 183   | CoreDoStaticArgs
 184   | CoreDoStrictness
 185   | CoreDoWorkerWrapper
 186   | CoreDoSpecialising
 187   | CoreDoSpecConstr
 188   | CoreDoUSPInf
 189   | CoreDoCPResult
 190   | CoreDoGlomBinds
 191   | CoreCSE
 192
 193   | CoreDoNothing        -- useful when building up lists of these things
 194 \end{code}
 195
 196 \begin{code}
 197 data StgToDo
 198   = StgDoMassageForProfiling  -- should be (next to) last
 199   -- There's also setStgVarInfo, but its absolute "lastness"
 200   -- is so critical that it is hardwired in (no flag).
 201   | D_stg_stats
 202 \end{code}
 203
 204 \begin{code}
 205 data SimplifierSwitch
 206   = MaxSimplifierIterations Int
 207   | SimplInlinePhase Int
 208   | DontApplyRules
 209   | NoCaseOfCase
 210   | SimplLetToCase
 211 \end{code}
 212
 213 %************************************************************************
 214 %*                                                                      *
 215 \subsection{Dynamic command-line options}
 216 %*                                                                      *
 217 %************************************************************************
 218
 219 \begin{code}
 220 data DynFlag
 221
 222    -- debugging flags
 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_sat
 239    | Opt_D_dump_stg
 240    | Opt_D_dump_stranal
 241    | Opt_D_dump_tc
 242    | Opt_D_dump_types
 243    | Opt_D_dump_rules
 244    | Opt_D_dump_usagesp
 245    | Opt_D_dump_cse
 246    | Opt_D_dump_worker_wrapper
 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_dump_tc_trace
 252    | Opt_D_dump_BCOs
 253    | Opt_D_source_stats
 254    | Opt_D_verbose_core2core
 255    | Opt_D_verbose_stg2stg
 256    | Opt_D_dump_hi
 257    | Opt_D_dump_hi_diffs
 258    | Opt_D_dump_minimal_imports
 259    | Opt_DoCoreLinting
 260    | Opt_DoStgLinting
 261    | Opt_DoUSPLinting
 262
 263    | Opt_WarnDuplicateExports
 264    | Opt_WarnHiShadows
 265    | Opt_WarnIncompletePatterns
 266    | Opt_WarnMissingFields
 267    | Opt_WarnMissingMethods
 268    | Opt_WarnMissingSigs
 269    | Opt_WarnNameShadowing
 270    | Opt_WarnOverlappingPatterns
 271    | Opt_WarnSimplePatterns
 272    | Opt_WarnTypeDefaults
 273    | Opt_WarnUnusedBinds
 274    | Opt_WarnUnusedImports
 275    | Opt_WarnUnusedMatches
 276    | Opt_WarnDeprecations
 277
 278    -- language opts
 279    | Opt_AllowOverlappingInstances
 280    | Opt_AllowUndecidableInstances
 281    | Opt_GlasgowExts
 282    | Opt_Generics
 283    | Opt_NoImplicitPrelude
 284
 285    deriving (Eq)
 286
 287 data DynFlags = DynFlags {
 288   coreToDo              :: [CoreToDo],
 289   stgToDo               :: [StgToDo],
 290   hscLang               :: HscLang,
 291   hscOutName            :: String,      -- name of the output file
 292   hscStubHOutName       :: String,      -- name of the .stub_h output file
 293   hscStubCOutName       :: String,      -- name of the .stub_c output file
 294   verbosity             :: Int,         -- verbosity level
 295   cppFlag               :: Bool,        -- preprocess with cpp?
 296   stolen_x86_regs       :: Int,
 297   cmdlineHcIncludes     :: [String],    -- -#includes
 298
 299   -- options for particular phases
 300   opt_L                 :: [String],
 301   opt_P                 :: [String],
 302   opt_c                 :: [String],
 303   opt_a                 :: [String],
 304   opt_m                 :: [String],
 305
 306   -- hsc dynamic flags
 307   flags                 :: [DynFlag]
 308  }
 309
 310 defaultDynFlags = DynFlags {
 311   coreToDo = [], stgToDo = [],
 312   hscLang = HscC,
 313   hscOutName = "",
 314   hscStubHOutName = "", hscStubCOutName = "",
 315   verbosity = 0,
 316   cppFlag               = False,
 317   stolen_x86_regs       = 4,
 318   cmdlineHcIncludes     = [],
 319   opt_L                 = [],
 320   opt_P                 = [],
 321   opt_c                 = [],
 322   opt_a                 = [],
 323   opt_m                 = [],
 324   flags = standardWarnings,
 325   }
 326
 327 {-
 328     Verbosity levels:
 329
 330     0   |   print errors & warnings only
 331     1   |   minimal verbosity: print "compiling M ... done." for each module.
 332     2   |   equivalent to -dshow-passes
 333     3   |   equivalent to existing "ghc -v"
 334     4   |   "ghc -v -ddump-most"
 335     5   |   "ghc -v -ddump-all"
 336 -}
 337
 338 dopt :: DynFlag -> DynFlags -> Bool
 339 dopt f dflags  = f `elem` (flags dflags)
 340
 341 dopt_CoreToDo :: DynFlags -> [CoreToDo]
 342 dopt_CoreToDo = coreToDo
 343
 344 dopt_StgToDo :: DynFlags -> [StgToDo]
 345 dopt_StgToDo = stgToDo
 346
 347 dopt_OutName :: DynFlags -> String
 348 dopt_OutName = hscOutName
 349
 350 data HscLang
 351   = HscC
 352   | HscAsm
 353   | HscJava
 354 #ifdef ILX
 355   | HscILX
 356 #endif
 357   | HscInterpreted
 358     deriving (Eq, Show)
 359
 360 dopt_HscLang :: DynFlags -> HscLang
 361 dopt_HscLang = hscLang
 362 \end{code}
 363
 364 %************************************************************************
 365 %*                                                                      *
 366 \subsection{Warnings}
 367 %*                                                                      *
 368 %************************************************************************
 369
 370 \begin{code}
 371 standardWarnings
 372     = [ Opt_WarnDeprecations,
 373         Opt_WarnOverlappingPatterns,
 374         Opt_WarnMissingFields,
 375         Opt_WarnMissingMethods,
 376         Opt_WarnDuplicateExports
 377       ]
 378
 379 minusWOpts
 380     = standardWarnings ++
 381       [ Opt_WarnUnusedBinds,
 382         Opt_WarnUnusedMatches,
 383         Opt_WarnUnusedImports,
 384         Opt_WarnIncompletePatterns
 385       ]
 386
 387 minusWallOpts
 388     = minusWOpts ++
 389       [ Opt_WarnTypeDefaults,
 390         Opt_WarnNameShadowing,
 391         Opt_WarnMissingSigs,
 392         Opt_WarnHiShadows
 393       ]
 394 \end{code}
 395
 396 %************************************************************************
 397 %*                                                                      *
 398 \subsection{Classifying command-line options}
 399 %*                                                                      *
 400 %************************************************************************
 401
 402 \begin{code}
 403 -- v_Statis_hsc_opts is here to avoid a circular dependency with
 404 -- main/DriverState.
 405 GLOBAL_VAR(v_Static_hsc_opts, [], [String])
 406
 407 lookUp           :: FAST_STRING -> Bool
 408 lookup_int       :: String -> Maybe Int
 409 lookup_def_int   :: String -> Int -> Int
 410 lookup_def_float :: String -> Float -> Float
 411 lookup_str       :: String -> Maybe String
 412
 413 unpacked_static_opts = unsafePerformIO (readIORef v_Static_hsc_opts)
 414 packed_static_opts   = map _PK_ unpacked_static_opts
 415
 416 lookUp     sw = sw `elem` packed_static_opts
 417
 418 lookup_str sw = firstJust (map (startsWith sw) unpacked_static_opts)
 419
 420 lookup_int sw = case (lookup_str sw) of
 421                   Nothing -> Nothing
 422                   Just xx -> Just (read xx)
 423
 424 lookup_def_int sw def = case (lookup_str sw) of
 425                             Nothing -> def              -- Use default
 426                             Just xx -> read xx
 427
 428 lookup_def_float sw def = case (lookup_str sw) of
 429                             Nothing -> def              -- Use default
 430                             Just xx -> read xx
 431
 432
 433 {-
 434  Putting the compiler options into temporary at-files
 435  may turn out to be necessary later on if we turn hsc into
 436  a pure Win32 application where I think there's a command-line
 437  length limit of 255. unpacked_opts understands the @ option.
 438
 439 unpacked_opts :: [String]
 440 unpacked_opts =
 441   concat $
 442   map (expandAts) $
 443   map _UNPK_ argv  -- NOT ARGV any more: v_Static_hsc_opts
 444   where
 445    expandAts ('@':fname) = words (unsafePerformIO (readFile fname))
 446    expandAts l = [l]
 447 -}
 448 \end{code}
 449
 450 %************************************************************************
 451 %*                                                                      *
 452 \subsection{Static options}
 453 %*                                                                      *
 454 %************************************************************************
 455
 456 \begin{code}
 457 -- debugging opts
 458 opt_PprStyle_NoPrags            = lookUp  SLIT("-dppr-noprags")
 459 opt_PprStyle_Debug              = lookUp  SLIT("-dppr-debug")
 460 opt_PprStyle_RawTypes           = lookUp  SLIT("-dppr-rawtypes")
 461 opt_PprUserLength               = lookup_def_int "-dppr-user-length" 5 --ToDo: give this a name
 462
 463 -- profiling opts
 464 opt_AutoSccsOnAllToplevs        = lookUp  SLIT("-fauto-sccs-on-all-toplevs")
 465 opt_AutoSccsOnExportedToplevs   = lookUp  SLIT("-fauto-sccs-on-exported-toplevs")
 466 opt_AutoSccsOnIndividualCafs    = lookUp  SLIT("-fauto-sccs-on-individual-cafs")
 467 opt_AutoSccsOnDicts             = lookUp  SLIT("-fauto-sccs-on-dicts")
 468 opt_SccProfilingOn              = lookUp  SLIT("-fscc-profiling")
 469 opt_DoTickyProfiling            = lookUp  SLIT("-fticky-ticky")
 470
 471 -- language opts
 472 opt_AllStrict                   = lookUp  SLIT("-fall-strict")
 473 opt_NoMonomorphismRestriction   = lookUp  SLIT("-fno-monomorphism-restriction")
 474 opt_DictsStrict                 = lookUp  SLIT("-fdicts-strict")
 475 opt_IrrefutableTuples           = lookUp  SLIT("-firrefutable-tuples")
 476 opt_MaxContextReductionDepth    = lookup_def_int "-fcontext-stack" mAX_CONTEXT_REDUCTION_DEPTH
 477 opt_NumbersStrict               = lookUp  SLIT("-fnumbers-strict")
 478 opt_Parallel                    = lookUp  SLIT("-fparallel")
 479 opt_SMP                         = lookUp  SLIT("-fsmp")
 480
 481 -- optimisation opts
 482 opt_NoMethodSharing             = lookUp  SLIT("-fno-method-sharing")
 483 opt_DoSemiTagging               = lookUp  SLIT("-fsemi-tagging")
 484 opt_FoldrBuildOn                = lookUp  SLIT("-ffoldr-build-on")
 485 opt_LiberateCaseThreshold       = lookup_def_int "-fliberate-case-threshold" (10::Int)
 486 opt_StgDoLetNoEscapes           = lookUp  SLIT("-flet-no-escape")
 487 opt_UnfoldCasms                 = lookUp  SLIT("-funfold-casms-in-hi-file")
 488 opt_UsageSPOn                   = lookUp  SLIT("-fusagesp-on")
 489 opt_UnboxStrictFields           = lookUp  SLIT("-funbox-strict-fields")
 490
 491 {-
 492    The optional '-inpackage=P' flag tells what package
 493    we are compiling this module for.
 494    The Prelude, for example is compiled with '-inpackage std'
 495 -}
 496 opt_InPackage                   = case lookup_str "-inpackage=" of
 497                                     Just p  -> _PK_ p
 498                                     Nothing -> SLIT("Main")     -- The package name if none is specified
 499
 500 opt_EmitCExternDecls            = lookUp  SLIT("-femit-extern-decls")
 501 opt_EnsureSplittableC           = lookUp  SLIT("-fglobalise-toplev-names")
 502 opt_GranMacros                  = lookUp  SLIT("-fgransim")
 503 opt_HiVersion                   = read cProjectVersionInt :: Int
 504 opt_HistorySize                 = lookup_def_int "-fhistory-size" 20
 505 opt_IgnoreAsserts               = lookUp  SLIT("-fignore-asserts")
 506 opt_IgnoreIfacePragmas          = lookUp  SLIT("-fignore-interface-pragmas")
 507 opt_NoHiCheck                   = lookUp  SLIT("-fno-hi-version-check")
 508 opt_OmitBlackHoling             = lookUp  SLIT("-dno-black-holing")
 509 opt_OmitInterfacePragmas        = lookUp  SLIT("-fomit-interface-pragmas")
 510 opt_KeepStgTypes                = lookUp  SLIT("-fkeep-stg-types")
 511
 512 -- Simplifier switches
 513 opt_SimplNoPreInlining          = lookUp  SLIT("-fno-pre-inlining")
 514         -- NoPreInlining is there just to see how bad things
 515         -- get if you don't do it!
 516 opt_SimplDoEtaReduction         = lookUp  SLIT("-fdo-eta-reduction")
 517 opt_SimplDoLambdaEtaExpansion   = lookUp  SLIT("-fdo-lambda-eta-expansion")
 518 opt_SimplCaseMerge              = lookUp  SLIT("-fcase-merge")
 519 opt_SimplExcessPrecision        = lookUp  SLIT("-fexcess-precision")
 520
 521 -- Unfolding control
 522 opt_UF_CreationThreshold        = lookup_def_int "-funfolding-creation-threshold"  (45::Int)
 523 opt_UF_UseThreshold             = lookup_def_int "-funfolding-use-threshold"       (8::Int)     -- Discounts can be big
 524 opt_UF_FunAppDiscount           = lookup_def_int "-funfolding-fun-discount"        (6::Int)     -- It's great to inline a fn
 525 opt_UF_KeenessFactor            = lookup_def_float "-funfolding-keeness-factor"    (1.5::Float)
 526 opt_UF_UpdateInPlace            = lookUp  SLIT("-funfolding-update-in-place")
 527
 528 opt_UF_CheapOp  = ( 1 :: Int)   -- Only one instruction; and the args are charged for
 529 opt_UF_DearOp   = ( 4 :: Int)
 530
 531 opt_NoPruneDecls                = lookUp  SLIT("-fno-prune-decls")
 532 opt_NoPruneTyDecls              = lookUp  SLIT("-fno-prune-tydecls")
 533 opt_Static                      = lookUp  SLIT("-static")
 534 opt_Unregisterised              = lookUp  SLIT("-funregisterised")
 535 \end{code}
 536
 537 %************************************************************************
 538 %*                                                                      *
 539 \subsection{List of static hsc flags}
 540 %*                                                                      *
 541 %************************************************************************
 542
 543 \begin{code}
 544 isStaticHscFlag f =
 545   f `elem` [
 546         "fauto-sccs-on-all-toplevs",
 547         "fauto-sccs-on-exported-toplevs",
 548         "fauto-sccs-on-individual-cafs",
 549         "fauto-sccs-on-dicts",
 550         "fscc-profiling",
 551         "fticky-ticky",
 552         "fall-strict",
 553         "fdicts-strict",
 554         "firrefutable-tuples",
 555         "fnumbers-strict",
 556         "fparallel",
 557         "fsmp",
 558         "fsemi-tagging",
 559         "ffoldr-build-on",
 560         "flet-no-escape",
 561         "funfold-casms-in-hi-file",
 562         "fusagesp-on",
 563         "funbox-strict-fields",
 564         "femit-extern-decls",
 565         "fglobalise-toplev-names",
 566         "fgransim",
 567         "fignore-asserts",
 568         "fignore-interface-pragmas",
 569         "fno-hi-version-check",
 570         "dno-black-holing",
 571         "fno-method-sharing",
 572         "fno-monomorphism-restriction",
 573         "fomit-interface-pragmas",
 574         "fkeep-stg-types",
 575         "fno-pre-inlining",
 576         "fdo-eta-reduction",
 577         "fdo-lambda-eta-expansion",
 578         "fcase-merge",
 579         "fexcess-precision",
 580         "funfolding-update-in-place",
 581         "fno-prune-decls",
 582         "fno-prune-tydecls",
 583         "static",
 584         "funregisterised"
 585         ]
 586   || any (flip prefixMatch f) [
 587         "fcontext-stack",
 588         "fliberate-case-threshold",
 589         "fhistory-size",
 590         "funfolding-creation-threshold",
 591         "funfolding-use-threshold",
 592         "funfolding-fun-discount",
 593         "funfolding-keeness-factor"
 594      ]
 595 \end{code}
 596
 597 %************************************************************************
 598 %*                                                                      *
 599 \subsection{Switch ordering}
 600 %*                                                                      *
 601 %************************************************************************
 602
 603 These things behave just like enumeration types.
 604
 605 \begin{code}
 606 instance Eq SimplifierSwitch where
 607     a == b = tagOf_SimplSwitch a ==# tagOf_SimplSwitch b
 608
 609 instance Ord SimplifierSwitch where
 610     a <  b  = tagOf_SimplSwitch a <# tagOf_SimplSwitch b
 611     a <= b  = tagOf_SimplSwitch a <=# tagOf_SimplSwitch b
 612
 613
 614 tagOf_SimplSwitch (SimplInlinePhase _)          = _ILIT(1)
 615 tagOf_SimplSwitch (MaxSimplifierIterations _)   = _ILIT(2)
 616 tagOf_SimplSwitch DontApplyRules                = _ILIT(3)
 617 tagOf_SimplSwitch SimplLetToCase                = _ILIT(4)
 618 tagOf_SimplSwitch NoCaseOfCase                  = _ILIT(5)
 619
 620 -- If you add anything here, be sure to change lAST_SIMPL_SWITCH_TAG, too!
 621
 622 lAST_SIMPL_SWITCH_TAG = 5
 623 \end{code}
 624
 625 %************************************************************************
 626 %*                                                                      *
 627 \subsection{Switch lookup}
 628 %*                                                                      *
 629 %************************************************************************
 630
 631 \begin{code}
 632 isAmongSimpl :: [SimplifierSwitch] -> SimplifierSwitch -> SwitchResult
 633 isAmongSimpl on_switches                -- Switches mentioned later occur *earlier*
 634                                         -- in the list; defaults right at the end.
 635   = let
 636         tidied_on_switches = foldl rm_dups [] on_switches
 637                 -- The fold*l* ensures that we keep the latest switches;
 638                 -- ie the ones that occur earliest in the list.
 639
 640         sw_tbl :: Array Int SwitchResult
 641         sw_tbl = (array (0, lAST_SIMPL_SWITCH_TAG) -- bounds...
 642                         all_undefined)
 643                  // defined_elems
 644
 645         all_undefined = [ (i, SwBool False) | i <- [0 .. lAST_SIMPL_SWITCH_TAG ] ]
 646
 647         defined_elems = map mk_assoc_elem tidied_on_switches
 648     in
 649     -- (avoid some unboxing, bounds checking, and other horrible things:)
 650 #if __GLASGOW_HASKELL__ < 405
 651     case sw_tbl of { Array bounds_who_needs_'em stuff ->
 652 #else
 653     case sw_tbl of { Array _ _ stuff ->
 654 #endif
 655     \ switch ->
 656         case (indexArray# stuff (tagOf_SimplSwitch switch)) of
 657 #if __GLASGOW_HASKELL__ < 400
 658           Lift v -> v
 659 #elif __GLASGOW_HASKELL__ < 403
 660           (# _, v #) -> v
 661 #else
 662           (# v #) -> v
 663 #endif
 664     }
 665   where
 666     mk_assoc_elem k@(MaxSimplifierIterations lvl)
 667         = (iBox (tagOf_SimplSwitch k), SwInt lvl)
 668     mk_assoc_elem k@(SimplInlinePhase n)
 669         = (iBox (tagOf_SimplSwitch k), SwInt n)
 670     mk_assoc_elem k
 671         = (iBox (tagOf_SimplSwitch k), SwBool True) -- I'm here, Mom!
 672
 673     -- cannot have duplicates if we are going to use the array thing
 674     rm_dups switches_so_far switch
 675       = if switch `is_elem` switches_so_far
 676         then switches_so_far
 677         else switch : switches_so_far
 678       where
 679         sw `is_elem` []     = False
 680         sw `is_elem` (s:ss) = (tagOf_SimplSwitch sw) ==# (tagOf_SimplSwitch s)
 681                             || sw `is_elem` ss
 682 \end{code}
 683
 684
 685 %************************************************************************
 686 %*                                                                      *
 687 \subsection{Misc functions for command-line options}
 688 %*                                                                      *
 689 %************************************************************************
 690
 691
 692 \begin{code}
 693 switchIsOn :: (switch -> SwitchResult) -> switch -> Bool
 694
 695 switchIsOn lookup_fn switch
 696   = case (lookup_fn switch) of
 697       SwBool False -> False
 698       _            -> True
 699
 700 intSwitchSet :: (switch -> SwitchResult)
 701              -> (Int -> switch)
 702              -> Maybe Int
 703
 704 intSwitchSet lookup_fn switch
 705   = case (lookup_fn (switch (panic "intSwitchSet"))) of
 706       SwInt int -> Just int
 707       _         -> Nothing
 708 \end{code}
 709
 710 \begin{code}
 711 startsWith :: String -> String -> Maybe String
 712 -- startsWith pfx (pfx++rest) = Just rest
 713
 714 startsWith []     str = Just str
 715 startsWith (c:cs) (s:ss)
 716   = if c /= s then Nothing else startsWith cs ss
 717 startsWith  _     []  = Nothing
 718
 719 endsWith  :: String -> String -> Maybe String
 720 endsWith cs ss
 721   = case (startsWith (reverse cs) (reverse ss)) of
 722       Nothing -> Nothing
 723       Just rs -> Just (reverse rs)
 724 \end{code}