Fix typos, via a Levenshtein-style corrector

compiler/GHC/Hs/Expr.hs

@@ -2572,7 +2572,7 @@ data ArithSeqInfo id
   | FromThenTo      (LHsExpr id)
                     (LHsExpr id)
                     (LHsExpr id)
--- AZ: Sould ArithSeqInfo have a TTG extension?
+-- AZ: Should ArithSeqInfo have a TTG extension?
 
 instance OutputableBndrId p
          => Outputable (ArithSeqInfo (GhcPass p)) where

compiler/GHC/Hs/Pat.hs

@@ -686,7 +686,7 @@ isIrrefutableHsPat :: (OutputableBndrId p) => LPat (GhcPass p) -> Bool
 -- Specifically on a ConPatIn, which is what it sees for a
 -- (LPat Name) in the renamer, it doesn't know the size of the
 -- constructor family, so it returns False.  Result: only
--- tuple patterns are considered irrefuable at the renamer stage.
+-- tuple patterns are considered irrefutable at the renamer stage.
 --
 -- But if it returns True, the pattern is definitely irrefutable
 isIrrefutableHsPat

compiler/GHC/Platform/Regs.hs

@@ -42,7 +42,7 @@ callerSaves platform
 -- The order matters (for the llvm backend anyway)! We must make sure to
 -- maintain the order here with the order used in the LLVM calling conventions.
 -- Note that also, this isn't all registers, just the ones that are currently
--- possbily mapped to real registers.
+-- possibly mapped to real registers.
 activeStgRegs :: Platform -> [GlobalReg]
 activeStgRegs platform
  | platformUnregisterised platform = NoRegs.activeStgRegs

compiler/GHC/StgToCmm/Bind.hs

@@ -198,7 +198,7 @@ cgRhs :: Id
                  CgIdInfo         -- The info for this binding
                , FCode CmmAGraph  -- A computation which will generate the
                                   -- code for the binding, and return an
-                                  -- assignent of the form "x = Hp - n"
+                                  -- assignment of the form "x = Hp - n"
                                   -- (see above)
                )
 

compiler/GHC/StgToCmm/ExtCode.hs

@@ -102,7 +102,7 @@ instance HasDynFlags CmmParse where
                                    return (d, dflags))
 
 
--- | Takes the variable decarations and imports from the monad
+-- | Takes the variable declarations and imports from the monad
 --      and makes an environment, which is looped back into the computation.
 --      In this way, we can have embedded declarations that scope over the whole
 --      procedure, and imports that scope over the entire module.

compiler/GHC/StgToCmm/Prim.hs

@@ -2159,7 +2159,7 @@ vecElemProjectCast _      _        _   =  Nothing
 --    values!
 --      The current design with respect to register mapping of scalars could
 --    very well be the best,but exploring the  design space and doing careful
---    measurments is the only only way to validate that.
+--    measurements is the only only way to validate that.
 --      In some next generation CPU ISAs, notably RISC V, the SIMD extension
 --    includes  support for a sort of run time CPU dependent vectorization parameter,
 --    where a loop may act upon a single scalar each iteration OR some 2,4,8 ...

compiler/basicTypes/OccName.hs

@@ -582,7 +582,7 @@ mk_deriv occ_sp sys_prefix str =
     mkOccNameFS occ_sp (concatFS $ sys_prefix : str)
 
 isDerivedOccName :: OccName -> Bool
--- ^ Test for definitions internally generated by GHC.  This predicte
+-- ^ Test for definitions internally generated by GHC.  This predicate
 -- is used to suppress printing of internal definitions in some debug prints
 isDerivedOccName occ =
    case occNameString occ of

compiler/basicTypes/VarSet.hs

@@ -319,7 +319,7 @@ seqDVarSet s = sizeDVarSet s `seq` ()
 extendDVarSetList :: DVarSet -> [Var] -> DVarSet
 extendDVarSetList = addListToUniqDSet
 
--- | Convert a DVarSet to a VarSet by forgeting the order of insertion
+-- | Convert a DVarSet to a VarSet by forgetting the order of insertion
 dVarSetToVarSet :: DVarSet -> VarSet
 dVarSetToVarSet = unsafeUFMToUniqSet . udfmToUfm . getUniqDSet
 

compiler/cmm/CmmBuildInfoTables.hs

@@ -227,7 +227,7 @@ implemented.
    case, if the closure is not locally defined then we can't point to
    it directly from the info table, because this is the text section
    which cannot contain runtime relocations. In this case we skip this
-   optimisation and generate the singleton SRT, becase SRTs are in the
+   optimisation and generate the singleton SRT, because SRTs are in the
    data section and *can* have relocatable references.
 
 2. [FUN] A static function closure can also be an SRT, we simply put

compiler/cmm/CmmMachOp.hs

@@ -135,7 +135,7 @@ data MachOp
   | MO_VU_Quot Length Width
   | MO_VU_Rem  Length Width
 
-  -- Floting point vector element insertion and extraction operations
+  -- Floating point vector element insertion and extraction operations
   | MO_VF_Insert  Length Width   -- Insert scalar into vector
   | MO_VF_Extract Length Width   -- Extract scalar from vector
 

compiler/cmm/CmmNode.hs

@@ -715,7 +715,7 @@ isTickSubScope = cmp
         cmp (SubScope u s) s'@(SubScope u' _)      = u == u' || cmp s s'
 
 -- | Combine two tick scopes. The new scope should be sub-scope of
--- both parameters. We simplfy automatically if one tick scope is a
+-- both parameters. We simplify automatically if one tick scope is a
 -- sub-scope of the other already.
 combineTickScopes :: CmmTickScope -> CmmTickScope -> CmmTickScope
 combineTickScopes s1 s2

compiler/cmm/CmmPipeline.hs

@@ -297,7 +297,7 @@ cpsTop hsc_env proc =
 --      Sp = Sp + 16
 --      ...y...y...
 --
--- But since we don't see any benefits from running sinking befroe stack
+-- But since we don't see any benefits from running sinking before stack
 -- layout, this situation probably doesn't arise too often in practice.
 --
 

compiler/cmm/SMRep.hs

@@ -15,7 +15,7 @@ module SMRep (
         StgHalfWord, fromStgHalfWord, toStgHalfWord,
         halfWordSize, halfWordSizeInBits,
 
-        -- * Closure repesentation
+        -- * Closure representation
         SMRep(..), -- CmmInfo sees the rep; no one else does
         IsStatic,
         ClosureTypeInfo(..), ArgDescr(..), Liveness,

compiler/cmm/cmm-notes

-More notes (Aug 11)
-~~~~~~~~~~~~~~~~~~
-* CmmInfo.cmmToRawCmm expands info tables to their representations
-  (needed for .cmm files as well as the code generators)
-
-* Why is FCode a lazy monad?  That makes it inefficient.
-  We want laziness to get code out one procedure at a time,
-  but not at the instruction level.
-  UPDATE (31/5/2016): FCode is strict since 09afcc9b.
-
-Things we did
-  * Remove CmmCvt.graphToZgraph (Conversion from old to new Cmm reps)
-  * Remove HscMain.optionallyConvertAndOrCPS (converted old Cmm to
-    new, ran pipeline, and converted back)
-  * Remove CmmDecl. Put its types in Cmm.  Import Cmm into OldCmm
-    so it can get those types.
-
-
-More notes (June 11)
-~~~~~~~~~~~~~~~~~~~~
-
-* In CmmContFlowOpts.branchChainElim, can a single block be the
-  successor of two calls?
-
-* Check in ClosureInfo:
-     -- NB: Results here should line up with the results of SMRep.rtsClosureType
-
-More notes (May 11)
-~~~~~~~~~~~~~~~~~~~
-In CmmNode, consider spliting CmmCall into two: call and jump
-
-Notes on new codegen (Aug 10)
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-Things to do:
- - Proc points pass all arguments on the stack, adding more code and
-   slowing down things a lot. We either need to fix this or even better
-   would be to get rid of proc points.
-
- - Sort out Label, LabelMap, LabelSet versus BlockId, BlockEnv, BlockSet
-   dichotomy. Mostly this means global replace, but we also need to make
-   Label an instance of Outputable (probably in the Outputable module).
-
-   EZY: We should use Label, since that's the terminology Hoopl uses.
-
- - AsmCodeGen has a generic Cmm optimiser; move this into new pipeline
-   EZY (2011-04-16): The mini-inliner has been generalized and ported,
-   but the constant folding and other optimizations need to still be
-   ported.
-
- - AsmCodeGen has post-native-cg branch eliminator (shortCutBranches);
-   we ultimately want to share this with the Cmm branch eliminator.
-
- - At the moment, references to global registers like Hp are "lowered" 
-   late (in CgUtils.fixStgRegisters). We should do this early, in the
-	new native codegen, much in the way that we lower calling conventions.
-	Might need to be a bit sophisticated about aliasing.
-
- - Move to new Cmm rep:
-     * Make native CG consume New Cmm; 
-     * Convert Old Cmm->New Cmm to keep old path alive
-     * Produce New Cmm when reading in .cmm files
-
- - Top-level SRT threading is a bit ugly
-
- - See "CAFs" below; we want to totally refactor the way SRTs are calculated
-
- - Garbage-collect https://gitlab.haskell.org/ghc/ghc/wikis/commentary/compiler/cps
-   moving good stuff into 
-   https://gitlab.haskell.org/ghc/ghc/wikis/commentary/compiler/new-code-gen-pipeline
-
- - Currently AsmCodeGen top level calls AsmCodeGen.cmmToCmm, which is a small
-   C-- optimiser.  It has quite a lot of boilerplate folding code in AsmCodeGen
-   (cmmBlockConFold, cmmStmtConFold, cmmExprConFold), before calling out to
-   CmmOpt.  ToDo: see what optimisations are being done; and do them before
-   AsmCodeGen.
-
- - If we stick CAF and stack liveness info on a LastCall node (not LastRet/Jump)
-   then all CAF and stack liveness stuff be completed before we split
-   into separate C procedures.
-
-   Short term:
-     compute and attach liveness into LastCall
-     right at end, split, cvt to old rep
-     [must split before cvt, because old rep is not expressive enough]
-
-   Longer term: 
-     when old rep disappears, 
-     move the whole splitting game into the C back end *only*
-	 (guided by the procpoint set)
-
-----------------------------------------------------
-	Proc-points
-----------------------------------------------------
-
-Consider this program, which has a diamond control flow, 
-with a call on one branch
- fn(p,x) {
-        h()
-	if b then { ... f(x) ...; q=5; goto J }
-             else { ...; q=7; goto J }
-     J: ..p...q...
-  }
-then the join point J is a "proc-point".  So, is 'p' passed to J
-as a parameter?  Or, if 'p' was saved on the stack anyway, perhaps
-to keep it alive across the call to h(), maybe 'p' gets communicated
-to J that way. This is an awkward choice.  (We think that we currently
-never pass variables to join points via arguments.)
-
-Furthermore, there is *no way* to pass q to J in a register (other
-than a parameter register).
-
-What we want is to do register allocation across the whole caboodle.
-Then we could drop all the code that deals with the above awkward
-decisions about spilling variables across proc-points.
-
-Note that J doesn't need an info table.
-
-What we really want is for each LastCall (not LastJump/Ret) 
-to have an info table.   Note that ProcPoints that are not successors
-of calls don't need an info table.
-
-Figuring out proc-points
-~~~~~~~~~~~~~~~~~~~~~~~~
-Proc-points are identified by
-CmmProcPoint.minimalProcPointSet/extendPPSet Although there isn't
-that much code, JD thinks that it could be done much more nicely using
-a dominator analysis, using the Dataflow Engine.
-
-----------------------------------------------------
-		CAFs
-----------------------------------------------------
-
-* The code for a procedure f may refer to either the *closure* 
-  or the *entry point* of another top-level procedure g.  
-  If f is live, then so is g.  f's SRT must include g's closure.
-
-* The CLabel for the entry-point/closure reveals whether g is 
-  a CAF (or refers to CAFs).  See the IdLabel constructor of CLabel.
-
-* The CAF-ness of the original top-level definitions is figured out
-  (by TidyPgm) before we generate C--.  This CafInfo is only set for
-  top-level Ids; nested bindings stay with MayHaveCafRefs.
-
-* Currently an SRT contains (only) pointers to (top-level) closures.
-
-* Consider this Core code
-	f = \x -> let g = \y -> ...x...y...h1...
-                  in ...h2...g...
-  and suppose that h1, h2 have IdInfo of MayHaveCafRefs.
-  Therefore, so will f,  But g will not (since it's nested).
-
-  This generates C-- roughly like this:
-     f_closure: .word f_entry
-     f_entry() [info-tbl-for-f] { ...jump g_entry...jump h2... }
-     g_entry() [info-tbl-for-g] { ...jump h1... }
-
-  Note that there is no top-level closure for g (only an info table).
-  This fact (whether or not there is a top-level closure) is recorded
-  in the InfoTable attached to the CmmProc for f, g
-  INVARIANT: 
-     Any out-of-Group references to an IdLabel goes to
-     a Proc whose InfoTable says "I have a top-level closure".
-  Equivalently: 
-     A CmmProc whose InfoTable says "I do not have a top-level
-     closure" is referred to only from its own Group.
-
-* So:   info-tbl-for-f must have an SRT that keeps h1,h2 alive
-        info-tbl-for-g must have an SRT that keeps h1 (only) alive
-
-  But if we just look for the free CAF refs, we get:
-	f   h2 (only)
-        g   h1
-
-  So we need to do a transitive closure thing to flesh out 
-  f's keep-alive refs to include h1.
-
-* The SRT info is the C_SRT field of Cmm.ClosureTypeInfo in a
-  CmmInfoTable attached to each CmmProc.  CmmPipeline.toTops actually does
-  the attaching, right at the end of the pipeline.  The C_SRT part
-  gives offsets within a single, shared table of closure pointers.
-
-* DECIDED: we can generate SRTs based on the final Cmm program
-  without knowledge of how it is generated.
-
+More notes (Aug 11)
+~~~~~~~~~~~~~~~~~~
+* CmmInfo.cmmToRawCmm expands info tables to their representations
+  (needed for .cmm files as well as the code generators)
+
+* Why is FCode a lazy monad?  That makes it inefficient.
+  We want laziness to get code out one procedure at a time,
+  but not at the instruction level.
+  UPDATE (31/5/2016): FCode is strict since 09afcc9b.
+
+Things we did
+  * Remove CmmCvt.graphToZgraph (Conversion from old to new Cmm reps)
+  * Remove HscMain.optionallyConvertAndOrCPS (converted old Cmm to
+    new, ran pipeline, and converted back)
+  * Remove CmmDecl. Put its types in Cmm.  Import Cmm into OldCmm
+    so it can get those types.
+
+
+More notes (June 11)
+~~~~~~~~~~~~~~~~~~~~
+
+* In CmmContFlowOpts.branchChainElim, can a single block be the
+  successor of two calls?
+
+* Check in ClosureInfo:
+     -- NB: Results here should line up with the results of SMRep.rtsClosureType
+
+More notes (May 11)
+~~~~~~~~~~~~~~~~~~~
+In CmmNode, consider splitting CmmCall into two: call and jump
+
+Notes on new codegen (Aug 10)
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Things to do:
+ - Proc points pass all arguments on the stack, adding more code and
+   slowing down things a lot. We either need to fix this or even better
+   would be to get rid of proc points.
+
+ - Sort out Label, LabelMap, LabelSet versus BlockId, BlockEnv, BlockSet
+   dichotomy. Mostly this means global replace, but we also need to make
+   Label an instance of Outputable (probably in the Outputable module).
+
+   EZY: We should use Label, since that's the terminology Hoopl uses.
+
+ - AsmCodeGen has a generic Cmm optimiser; move this into new pipeline
+   EZY (2011-04-16): The mini-inliner has been generalized and ported,
+   but the constant folding and other optimizations need to still be
+   ported.
+
+ - AsmCodeGen has post-native-cg branch eliminator (shortCutBranches);
+   we ultimately want to share this with the Cmm branch eliminator.
+
+ - At the moment, references to global registers like Hp are "lowered" 
+   late (in CgUtils.fixStgRegisters). We should do this early, in the
+	new native codegen, much in the way that we lower calling conventions.
+	Might need to be a bit sophisticated about aliasing.
+
+ - Move to new Cmm rep:
+     * Make native CG consume New Cmm; 
+     * Convert Old Cmm->New Cmm to keep old path alive
+     * Produce New Cmm when reading in .cmm files
+
+ - Top-level SRT threading is a bit ugly
+
+ - See "CAFs" below; we want to totally refactor the way SRTs are calculated
+
+ - Garbage-collect https://gitlab.haskell.org/ghc/ghc/wikis/commentary/compiler/cps
+   moving good stuff into 
+   https://gitlab.haskell.org/ghc/ghc/wikis/commentary/compiler/new-code-gen-pipeline
+
+ - Currently AsmCodeGen top level calls AsmCodeGen.cmmToCmm, which is a small
+   C-- optimiser.  It has quite a lot of boilerplate folding code in AsmCodeGen
+   (cmmBlockConFold, cmmStmtConFold, cmmExprConFold), before calling out to
+   CmmOpt.  ToDo: see what optimisations are being done; and do them before
+   AsmCodeGen.
+
+ - If we stick CAF and stack liveness info on a LastCall node (not LastRet/Jump)
+   then all CAF and stack liveness stuff be completed before we split
+   into separate C procedures.
+
+   Short term:
+     compute and attach liveness into LastCall
+     right at end, split, cvt to old rep
+     [must split before cvt, because old rep is not expressive enough]
+
+   Longer term: 
+     when old rep disappears, 
+     move the whole splitting game into the C back end *only*
+	 (guided by the procpoint set)
+
+----------------------------------------------------
+	Proc-points
+----------------------------------------------------
+
+Consider this program, which has a diamond control flow, 
+with a call on one branch
+ fn(p,x) {
+        h()
+	if b then { ... f(x) ...; q=5; goto J }
+             else { ...; q=7; goto J }
+     J: ..p...q...
+  }
+then the join point J is a "proc-point".  So, is 'p' passed to J
+as a parameter?  Or, if 'p' was saved on the stack anyway, perhaps
+to keep it alive across the call to h(), maybe 'p' gets communicated
+to J that way. This is an awkward choice.  (We think that we currently
+never pass variables to join points via arguments.)
+
+Furthermore, there is *no way* to pass q to J in a register (other
+than a parameter register).
+
+What we want is to do register allocation across the whole caboodle.
+Then we could drop all the code that deals with the above awkward
+decisions about spilling variables across proc-points.
+
+Note that J doesn't need an info table.
+
+What we really want is for each LastCall (not LastJump/Ret) 
+to have an info table.   Note that ProcPoints that are not successors
+of calls don't need an info table.
+
+Figuring out proc-points
+~~~~~~~~~~~~~~~~~~~~~~~~
+Proc-points are identified by
+CmmProcPoint.minimalProcPointSet/extendPPSet Although there isn't
+that much code, JD thinks that it could be done much more nicely using
+a dominator analysis, using the Dataflow Engine.
+
+----------------------------------------------------
+		CAFs
+----------------------------------------------------
+
+* The code for a procedure f may refer to either the *closure* 
+  or the *entry point* of another top-level procedure g.  
+  If f is live, then so is g.  f's SRT must include g's closure.
+
+* The CLabel for the entry-point/closure reveals whether g is 
+  a CAF (or refers to CAFs).  See the IdLabel constructor of CLabel.
+
+* The CAF-ness of the original top-level definitions is figured out
+  (by TidyPgm) before we generate C--.  This CafInfo is only set for
+  top-level Ids; nested bindings stay with MayHaveCafRefs.
+
+* Currently an SRT contains (only) pointers to (top-level) closures.
+
+* Consider this Core code
+	f = \x -> let g = \y -> ...x...y...h1...
+                  in ...h2...g...
+  and suppose that h1, h2 have IdInfo of MayHaveCafRefs.
+  Therefore, so will f,  But g will not (since it's nested).
+
+  This generates C-- roughly like this:
+     f_closure: .word f_entry
+     f_entry() [info-tbl-for-f] { ...jump g_entry...jump h2... }
+     g_entry() [info-tbl-for-g] { ...jump h1... }
+
+  Note that there is no top-level closure for g (only an info table).
+  This fact (whether or not there is a top-level closure) is recorded
+  in the InfoTable attached to the CmmProc for f, g
+  INVARIANT: 
+     Any out-of-Group references to an IdLabel goes to
+     a Proc whose InfoTable says "I have a top-level closure".
+  Equivalently: 
+     A CmmProc whose InfoTable says "I do not have a top-level
+     closure" is referred to only from its own Group.
+
+* So:   info-tbl-for-f must have an SRT that keeps h1,h2 alive
+        info-tbl-for-g must have an SRT that keeps h1 (only) alive
+
+  But if we just look for the free CAF refs, we get:
+	f   h2 (only)
+        g   h1
+
+  So we need to do a transitive closure thing to flesh out 
+  f's keep-alive refs to include h1.
+
+* The SRT info is the C_SRT field of Cmm.ClosureTypeInfo in a
+  CmmInfoTable attached to each CmmProc.  CmmPipeline.toTops actually does
+  the attaching, right at the end of the pipeline.  The C_SRT part
+  gives offsets within a single, shared table of closure pointers.
+
+* DECIDED: we can generate SRTs based on the final Cmm program
+  without knowledge of how it is generated.
+

compiler/coreSyn/CoreFVs.hs

@@ -496,7 +496,7 @@ ruleLhsFreeIds = fvVarSet . ruleLhsFVIds
 
 ruleLhsFreeIdsList :: CoreRule -> [Var]
 -- ^ This finds all locally-defined free Ids on the left hand side of a rule
+-- and returns them as a deterministically ordered list
 ruleLhsFreeIdsList = fvVarList . ruleLhsFVIds
 
 ruleLhsFVIds :: CoreRule -> FV

compiler/coreSyn/CoreLint.hs

@@ -166,7 +166,7 @@ That is, use a type let.   See Note [Type let] in CoreSyn.
 
 However, when linting <body> we need to remember that a=Int, else we might
 reject a correct program.  So we carry a type substitution (in this example
-[a -> Int]) and apply this substitution before comparing types.  The functin
+[a -> Int]) and apply this substitution before comparing types.  The function
         lintInTy :: Type -> LintM (Type, Kind)
 returns a substituted type.
 

compiler/coreSyn/CoreSubst.hs

@@ -745,7 +745,7 @@ Breakpoints can't handle free variables with unlifted types anyway.
 {-
 Note [Worker inlining]
 ~~~~~~~~~~~~~~~~~~~~~~
-A worker can get sustituted away entirely.
+A worker can get substituted away entirely.
         - it might be trivial
         - it might simply be very small
 We do not treat an InlWrapper as an 'occurrence' in the occurrence

compiler/coreSyn/CoreTidy.hs

@@ -196,7 +196,7 @@ tidyLetBndr rec_tidy_env env@(tidy_env, var_env) id
         -- Don't attempt to recompute arity here; this is just tidying!
         -- Trying to do so led to #17294
         --
-        -- Set inline-prag info so that we preseve it across
+        -- Set inline-prag info so that we preserve it across
         -- separate compilation boundaries
         old_info = idInfo id
         new_info = vanillaIdInfo

compiler/coreSyn/MkCore.hs

@@ -886,7 +886,7 @@ After doing case-of-known-constructor, and expanding $WMkT we get
 Yikes!  That bogusly appears to evaluate the absentError!
 
 This is extremely tiresome.  Another way to think of this is that, in
-Core, it is an invariant that a strict data contructor, like MkT, must
+Core, it is an invariant that a strict data constructor, like MkT, must
 be applied only to an argument in HNF. So (absentError "blah") had
 better be non-bottom.
 

compiler/deSugar/DsListComp.hs

@@ -380,7 +380,7 @@ dfBindComp c_id n_id (pat, core_list1) quals = do
     b <- newSysLocalDs b_ty
     x <- newSysLocalDs x_ty
 
-    -- build rest of the comprehesion
+    -- build rest of the comprehension
     core_rest <- dfListComp c_id b quals
 
     -- build the pattern match