ghc-9.4.1: GHC/StgToCmm/Ticky.hs
{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE MultiWayIf #-}
-----------------------------------------------------------------------------
--
-- Code generation for ticky-ticky profiling
--
-- (c) The University of Glasgow 2004-2006
--
-----------------------------------------------------------------------------
{- OVERVIEW: ticky ticky profiling
Please see
https://gitlab.haskell.org/ghc/ghc/wikis/debugging/ticky-ticky and also
edit it and the rest of this comment to keep them up-to-date if you
change ticky-ticky. Thanks!
*** All allocation ticky numbers are in bytes. ***
Some of the relevant source files:
***not necessarily an exhaustive list***
* some codeGen/ modules import this one
* this module imports GHC.Cmm.CLabel to manage labels
* GHC.Cmm.Parser expands some macros using generators defined in
this module
* rts/include/stg/Ticky.h declares all of the global counters
* rts/include/rts/Ticky.h declares the C data type for an
STG-declaration's counters
* some macros defined in rts/include/Cmm.h (and used within the RTS's
CMM code) update the global ticky counters
* at the end of execution rts/Ticky.c generates the final report
+RTS -r<report-file> -RTS
The rts/Ticky.c function that generates the report includes an
STG-declaration's ticky counters if
* that declaration was entered, or
* it was allocated (if -ticky-allocd)
On either of those events, the counter is "registered" by adding it to
a linked list; cf the CMM generated by registerTickyCtr.
Ticky-ticky profiling has evolved over many years. Many of the
counters from its most sophisticated days are no longer
active/accurate. As the RTS has changed, sometimes the ticky code for
relevant counters was not accordingly updated. Unfortunately, neither
were the comments.
As of March 2013, there still exist deprecated code and comments in
the code generator as well as the RTS because:
* I don't know what is out-of-date versus merely commented out for
momentary convenience, and
* someone else might know how to repair it!
Note [Ticky counters are static]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Currently GHC only supports static ticky events. That is -ticky emits
code containing labels containing counters which then get bumped at runtime.
There are currently only *static* ticky counters. Either we bump one of the
static counters included in the RTS. Or we emit StgEntCounter structures in
the object code and bump these.
-}
module GHC.StgToCmm.Ticky (
withNewTickyCounterFun,
withNewTickyCounterLNE,
withNewTickyCounterThunk,
withNewTickyCounterStdThunk,
withNewTickyCounterCon,
emitTickyCounterTag,
tickyDynAlloc,
tickyAllocHeap,
tickyAllocPrim,
tickyAllocThunk,
tickyAllocPAP,
tickyHeapCheck,
tickyStackCheck,
tickyDirectCall,
tickyPushUpdateFrame,
tickyUpdateFrameOmitted,
tickyEnterDynCon,
tickyEnterFun,
tickyEnterThunk,
tickyEnterLNE,
tickyUpdateBhCaf,
tickyUnboxedTupleReturn,
tickyReturnOldCon, tickyReturnNewCon,
tickyKnownCallTooFewArgs, tickyKnownCallExact, tickyKnownCallExtraArgs,
tickySlowCall, tickySlowCallPat,
tickyTagged, tickyUntagged, tickyTagSkip
) where
import GHC.Prelude
import GHC.Platform
import GHC.Platform.Profile
import GHC.StgToCmm.ArgRep ( slowCallPattern , toArgRep , argRepString )
import GHC.StgToCmm.Closure
import GHC.StgToCmm.Config
import {-# SOURCE #-} GHC.StgToCmm.Foreign ( emitPrimCall )
import GHC.StgToCmm.Lit ( newStringCLit )
import GHC.StgToCmm.Monad
import GHC.StgToCmm.Utils
import GHC.Stg.Syntax
import GHC.Cmm.Expr
import GHC.Cmm.Graph
import GHC.Cmm.Utils
import GHC.Cmm.CLabel
import GHC.Runtime.Heap.Layout
import GHC.Types.Name
import GHC.Types.Id
import GHC.Types.Basic
import GHC.Data.FastString
import GHC.Utils.Outputable
import GHC.Utils.Panic
import GHC.Utils.Misc
import GHC.Utils.Monad (whenM)
-- Turgid imports for showTypeCategory
import GHC.Builtin.Names
import GHC.Tc.Utils.TcType
import GHC.Core.DataCon
import GHC.Core.TyCon
import GHC.Core.Predicate
import Data.Maybe
import qualified Data.Char
import Control.Monad ( when, unless )
import GHC.Types.Id.Info
import GHC.Utils.Trace
import GHC.StgToCmm.Env (getCgInfo_maybe)
import Data.Coerce (coerce)
import GHC.Utils.Json
-----------------------------------------------------------------------------
--
-- Ticky-ticky profiling
--
-----------------------------------------------------------------------------
-- | Number of arguments for a ticky counter.
--
-- Ticky currently treats args to constructor allocations differently than those for functions/LNE bindings.
tickyArgArity :: TickyClosureType -> Int
tickyArgArity (TickyFun _ _fvs args) = length args
tickyArgArity (TickyLNE args) = length args
tickyArgArity (TickyCon{}) = 0
tickyArgArity (TickyThunk{}) = 0
tickyArgDesc :: TickyClosureType -> String
tickyArgDesc arg_info =
case arg_info of
TickyFun _ _fvs args -> map (showTypeCategory . idType . fromNonVoid) args
TickyLNE args -> map (showTypeCategory . idType . fromNonVoid) args
TickyThunk{} -> ""
TickyCon{} -> ""
tickyFvDesc :: TickyClosureType -> String
tickyFvDesc arg_info =
case arg_info of
TickyFun _ fvs _args -> map (showTypeCategory . idType . fromNonVoid) fvs
TickyLNE{} -> ""
TickyThunk _ _ fvs -> map (showTypeCategory . stgArgType) fvs
TickyCon{} -> ""
instance ToJson TickyClosureType where
json info = case info of
(TickyFun {}) -> mkInfo (tickyFvDesc info) (tickyArgDesc info) "fun"
(TickyLNE {}) -> mkInfo [] (tickyArgDesc info) "lne"
(TickyThunk uf _ _) -> mkInfo (tickyFvDesc info) [] ("thk" ++ if uf then "_u" else "")
(TickyCon{}) -> mkInfo [] [] "con"
where
mkInfo :: String -> String -> String -> JsonDoc
mkInfo fvs args ty =
JSObject
[("type", json "entCntr")
,("subTy", json ty)
,("fvs_c", json (length fvs))
,("fvs" , json fvs)
,("args", json args)
]
tickyEntryDescJson :: (SDocContext -> TickyClosureType -> String)
tickyEntryDescJson ctxt = renderWithContext ctxt . renderJSON . json
data TickyClosureType
= TickyFun
Bool -- True <-> single entry
[NonVoid Id] -- ^ FVs
[NonVoid Id] -- ^ Args
| TickyCon
DataCon -- the allocated constructor
ConstructorNumber
| TickyThunk
Bool -- True <-> updateable
Bool -- True <-> standard thunk (AP or selector), has no entry counter
[StgArg] -- ^ FVS, StgArg because for thunks these can also be literals.
| TickyLNE
[NonVoid Id] -- ^ Args
withNewTickyCounterFun :: Bool -> Id -> [NonVoid Id] -> [NonVoid Id] -> FCode a -> FCode a
withNewTickyCounterFun single_entry f fvs args = withNewTickyCounter (TickyFun single_entry fvs args) f
withNewTickyCounterLNE :: Id -> [NonVoid Id] -> FCode a -> FCode a
withNewTickyCounterLNE nm args code = do
b <- isEnabled stgToCmmTickyLNE
if not b then code else withNewTickyCounter (TickyLNE args) nm code
thunkHasCounter :: Bool -> FCode Bool
thunkHasCounter isStatic = (not isStatic &&) <$> isEnabled stgToCmmTickyDynThunk
withNewTickyCounterThunk
:: Bool -- ^ static
-> Bool -- ^ updateable
-> Id
-> [NonVoid Id] -- ^ Free vars
-> FCode a
-> FCode a
withNewTickyCounterThunk isStatic isUpdatable name fvs code = do
has_ctr <- thunkHasCounter isStatic
if not has_ctr
then code
else withNewTickyCounter (TickyThunk isUpdatable False (map StgVarArg $ coerce fvs)) name code
withNewTickyCounterStdThunk
:: Bool -- ^ updateable
-> Id
-> [StgArg] -- ^ Free vars + function
-> FCode a
-> FCode a
withNewTickyCounterStdThunk isUpdatable name fvs code = do
has_ctr <- thunkHasCounter False
if not has_ctr
then code
else withNewTickyCounter (TickyThunk isUpdatable True fvs) name code
withNewTickyCounterCon
:: Id
-> DataCon
-> ConstructorNumber
-> FCode a
-> FCode a
withNewTickyCounterCon name datacon info code = do
has_ctr <- thunkHasCounter False
if not has_ctr
then code
else withNewTickyCounter (TickyCon datacon info) name code
-- args does not include the void arguments
withNewTickyCounter :: TickyClosureType -> Id -> FCode a -> FCode a
withNewTickyCounter cloType name m = do
lbl <- emitTickyCounter cloType name
setTickyCtrLabel lbl m
emitTickyData :: Platform
-> CLabel -- ^ lbl for the counter
-> Arity -- ^ arity
-> CmmLit -- ^ fun desc
-> CmmLit -- ^ arg desc
-> CmmLit -- ^ json desc
-> CmmLit -- ^ info table lbl
-> FCode ()
emitTickyData platform ctr_lbl arity fun_desc arg_desc json_desc info_tbl =
emitDataLits ctr_lbl
-- Must match layout of rts/include/rts/Ticky.h's StgEntCounter
--
-- krc: note that all the fields are I32 now; some were I16
-- before, but the code generator wasn't handling that
-- properly and it led to chaos, panic and disorder.
[ zeroCLit platform, -- registered?
mkIntCLit platform arity, -- Arity
zeroCLit platform, -- Heap allocated for this thing
fun_desc,
arg_desc,
json_desc,
info_tbl,
zeroCLit platform, -- Entries into this thing
zeroCLit platform, -- Heap allocated by this thing
zeroCLit platform -- Link to next StgEntCounter
]
emitTickyCounter :: TickyClosureType -> Id -> FCode CLabel
emitTickyCounter cloType tickee
= let name = idName tickee in
let ctr_lbl = mkRednCountsLabel name in
(>> return ctr_lbl) $
ifTicky $ do
{ cfg <- getStgToCmmConfig
; parent <- getTickyCtrLabel
; mod_name <- getModuleName
-- When printing the name of a thing in a ticky file, we
-- want to give the module name even for *local* things. We
-- print just "x (M)" rather that "M.x" to distinguish them
-- from the global kind by calling to @pprTickyName@
; let platform = stgToCmmPlatform cfg
ppr_for_ticky_name :: SDoc
ppr_for_ticky_name =
let ext = case cloType of
TickyFun single_entry _ _-> parens $ hcat $ punctuate comma $
[text "fun"] ++ [text "se"|single_entry]
TickyCon datacon _cn -> parens (text "con:" <+> ppr (dataConName datacon))
TickyThunk upd std _-> parens $ hcat $ punctuate comma $
[text "thk"] ++ [text "se"|not upd] ++ [text "std"|std]
TickyLNE _ | isInternalName name -> parens (text "LNE")
| otherwise -> panic "emitTickyCounter: how is this an external LNE?"
p = case hasHaskellName parent of
-- NB the default "top" ticky ctr does not
-- have a Haskell name
Just pname -> text "in" <+> ppr (nameUnique pname)
_ -> empty
in pprTickyName mod_name name <+> ext <+> p
; this_mod <- getModuleName
; let t = case cloType of
TickyCon {} -> "C"
TickyFun {} -> "F"
TickyThunk {} -> "T"
TickyLNE {} -> "L"
; info_lbl <- case cloType of
TickyCon dc mn -> case mn of
NoNumber -> return $! CmmLabel $ mkConInfoTableLabel (dataConName dc) DefinitionSite
(Numbered n) -> return $! CmmLabel $ mkConInfoTableLabel (dataConName dc) (UsageSite this_mod n)
TickyFun {} ->
return $! CmmLabel $ mkInfoTableLabel name NoCafRefs
TickyThunk _ std_thunk _fvs
| not std_thunk
-> return $! CmmLabel $ mkInfoTableLabel name NoCafRefs
-- IPE Maps have no entry for std thunks.
| otherwise
-> do
lf_info <- getCgInfo_maybe name
profile <- getProfile
case lf_info of
Just (CgIdInfo { cg_lf = cg_lf })
| isLFThunk cg_lf
-> return $! CmmLabel $ mkClosureInfoTableLabel (profilePlatform profile) tickee cg_lf
_ -> pprTraceDebug "tickyThunkUnknown" (text t <> colon <> ppr name <+> ppr (mkInfoTableLabel name NoCafRefs))
return $! zeroCLit platform
TickyLNE {} -> return $! zeroCLit platform
; let ctx = defaultSDocContext {sdocPprDebug = True}
; fun_descr_lit <- newStringCLit $ renderWithContext ctx ppr_for_ticky_name
; arg_descr_lit <- newStringCLit $ tickyArgDesc cloType
; json_descr_lit <- newStringCLit $ tickyEntryDescJson ctx cloType
; emitTickyData platform ctr_lbl (tickyArgArity cloType) fun_descr_lit arg_descr_lit json_descr_lit info_lbl
}
{- Note [TagSkip ticky counters]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
These counters keep track how often we execute code where we
would have performed a tag check if we hadn't run tag inference.
If we have some code of the form:
case v[tagged] of ...
and we want to record how often we avoid a tag check on v
through tag inference we have to emit a new StgEntCounter for
each such case statement in order to record how often it's executed.
In theory we could emit one per *binding*. But then we
would have to either keep track of the bindings which
already have a StgEntCounter associated with them in the
code gen state or preallocate such a structure for each binding
in the code unconditionally (since ticky-code can call non-ticky code)
The first makes the compiler slower, even when ticky is not
used (a big no no). The later is fairly complex but increases code size
unconditionally. See also Note [Ticky counters are static].
So instead we emit a new StgEntCounter for each use site of a binding
where we infered a tag to be present. And increment the counter whenever
this use site is executed.
We use the fields as follows:
entry_count: Entries avoided.
str: : Name of the id.
We use emitTickyCounterTag to emit the counter.
Unlike the closure counters each *use* site of v has it's own
counter. So there is no need to keep track of the closure/case we are
in.
We also have to pass a unique for the counter. An Id might be
scrutinized in more than one place, so the ID alone isn't enough
to distinguish between use sites.
-}
emitTickyCounterTag :: Unique -> NonVoid Id -> FCode CLabel
emitTickyCounterTag unique (NonVoid id) =
let name = idName id
ctr_lbl = mkTagHitLabel name unique in
(>> return ctr_lbl) $
ifTickyTag $ do
{ platform <- getPlatform
; parent <- getTickyCtrLabel
; mod_name <- getModuleName
-- When printing the name of a thing in a ticky file, we
-- want to give the module name even for *local* things. We
-- print just "x (M)" rather that "M.x" to distinguish them
-- from the global kind.
; let ppr_for_ticky_name :: SDoc
ppr_for_ticky_name =
let n = ppr name
ext = empty -- parens (text "tagged")
p = case hasHaskellName parent of
-- NB the default "top" ticky ctr does not
-- have a Haskell name
Just pname -> text "at" <+> ppr (nameSrcLoc pname) <+>
text "in" <+> pprNameUnqualified name
_ -> empty
in if isInternalName name
then n <+> parens (ppr mod_name) <+> ext <+> p
else n <+> ext <+> p
; sdoc_context <- stgToCmmContext <$> getStgToCmmConfig
; fun_descr_lit <- newStringCLit $ renderWithContext sdoc_context ppr_for_ticky_name
; arg_descr_lit <- newStringCLit $ "infer"
; json_descr_lit <- newStringCLit $ "infer"
; emitTickyData platform ctr_lbl 0 fun_descr_lit arg_descr_lit json_descr_lit (zeroCLit platform)
}
-- -----------------------------------------------------------------------------
-- Ticky stack frames
tickyPushUpdateFrame, tickyUpdateFrameOmitted :: FCode ()
tickyPushUpdateFrame = ifTicky $ bumpTickyCounter (fsLit "UPDF_PUSHED_ctr")
tickyUpdateFrameOmitted = ifTicky $ bumpTickyCounter (fsLit "UPDF_OMITTED_ctr")
-- -----------------------------------------------------------------------------
-- Ticky entries
-- NB the name-specific entries are only available for names that have
-- dedicated Cmm code. As far as I know, this just rules out
-- constructor thunks. For them, there is no CMM code block to put the
-- bump of name-specific ticky counter into. On the other hand, we can
-- still track allocation their allocation.
tickyEnterDynCon :: FCode ()
tickyEnterDynCon = ifTicky $ bumpTickyCounter (fsLit "ENT_DYN_CON_ctr")
tickyEnterThunk :: ClosureInfo -> FCode ()
tickyEnterThunk cl_info
= ifTicky $ do
{ bumpTickyCounter ctr
; has_ctr <- thunkHasCounter static
; when has_ctr $ do
ticky_ctr_lbl <- getTickyCtrLabel
registerTickyCtrAtEntryDyn ticky_ctr_lbl
bumpTickyEntryCount ticky_ctr_lbl }
where
updatable = not (closureUpdReqd cl_info)
static = isStaticClosure cl_info
ctr | static = if updatable then fsLit "ENT_STATIC_THK_SINGLE_ctr"
else fsLit "ENT_STATIC_THK_MANY_ctr"
| otherwise = if updatable then fsLit "ENT_DYN_THK_SINGLE_ctr"
else fsLit "ENT_DYN_THK_MANY_ctr"
tickyUpdateBhCaf :: ClosureInfo -> FCode ()
tickyUpdateBhCaf cl_info
= ifTicky (bumpTickyCounter ctr)
where
ctr | closureUpdReqd cl_info = (fsLit "UPD_CAF_BH_SINGLE_ENTRY_ctr")
| otherwise = (fsLit "UPD_CAF_BH_UPDATABLE_ctr")
tickyEnterFun :: ClosureInfo -> FCode ()
tickyEnterFun cl_info = ifTicky $ do
ctr_lbl <- getTickyCtrLabel
if isStaticClosure cl_info
then do bumpTickyCounter (fsLit "ENT_STATIC_FUN_DIRECT_ctr")
registerTickyCtr ctr_lbl
else do bumpTickyCounter (fsLit "ENT_DYN_FUN_DIRECT_ctr")
registerTickyCtrAtEntryDyn ctr_lbl
bumpTickyEntryCount ctr_lbl
tickyEnterLNE :: FCode ()
tickyEnterLNE = ifTicky $ do
bumpTickyCounter (fsLit "ENT_LNE_ctr")
ifTickyLNE $ do
ctr_lbl <- getTickyCtrLabel
registerTickyCtr ctr_lbl
bumpTickyEntryCount ctr_lbl
-- needn't register a counter upon entry if
--
-- 1) it's for a dynamic closure, and
--
-- 2) -ticky-allocd is on
--
-- since the counter was registered already upon being alloc'd
registerTickyCtrAtEntryDyn :: CLabel -> FCode ()
registerTickyCtrAtEntryDyn ctr_lbl = do
already_registered <- isEnabled stgToCmmTickyAllocd
unless already_registered $ registerTickyCtr ctr_lbl
-- | Register a ticky counter.
--
-- It's important that this does not race with other entries of the same
-- closure, lest the ticky_entry_ctrs list may become cyclic. However, we also
-- need to make sure that this is reasonably efficient. Consequently, we first
-- perform a normal load of the counter's "registered" flag to check whether
-- registration is necessary. If so, then we do a compare-and-swap to lock the
-- counter for registration and use an atomic-exchange to add the counter to the list.
--
-- @
-- if ( f_ct.registeredp == 0 ) {
-- if (cas(f_ct.registeredp, 0, 1) == 0) {
-- old_head = xchg(ticky_entry_ctrs, f_ct);
-- f_ct.link = old_head;
-- }
-- }
-- @
registerTickyCtr :: CLabel -> FCode ()
registerTickyCtr ctr_lbl = do
platform <- getPlatform
let constants = platformConstants platform
word_width = wordWidth platform
registeredp = CmmLit (cmmLabelOffB ctr_lbl (pc_OFFSET_StgEntCounter_registeredp constants))
register_stmts <- getCode $ do
old_head <- newTemp (bWord platform)
let ticky_entry_ctrs = mkLblExpr (mkRtsCmmDataLabel (fsLit "ticky_entry_ctrs"))
link = CmmLit (cmmLabelOffB ctr_lbl (pc_OFFSET_StgEntCounter_link constants))
emitPrimCall [old_head] (MO_Xchg word_width) [ticky_entry_ctrs, mkLblExpr ctr_lbl]
emitStore link (CmmReg $ CmmLocal old_head)
cas_test <- getCode $ do
old <- newTemp (bWord platform)
emitPrimCall [old] (MO_Cmpxchg word_width)
[registeredp, zeroExpr platform, mkIntExpr platform 1]
let locked = cmmEqWord platform (CmmReg $ CmmLocal old) (zeroExpr platform)
emit =<< mkCmmIfThen locked register_stmts
let test = cmmEqWord platform (cmmLoadBWord platform registeredp) (zeroExpr platform)
emit =<< mkCmmIfThen test cas_test
tickyReturnOldCon, tickyReturnNewCon :: RepArity -> FCode ()
tickyReturnOldCon arity
= ifTicky $ do { bumpTickyCounter (fsLit "RET_OLD_ctr")
; bumpHistogram (fsLit "RET_OLD_hst") arity }
tickyReturnNewCon arity
= ifTicky $ do { bumpTickyCounter (fsLit "RET_NEW_ctr")
; bumpHistogram (fsLit "RET_NEW_hst") arity }
tickyUnboxedTupleReturn :: RepArity -> FCode ()
tickyUnboxedTupleReturn arity
= ifTicky $ do { bumpTickyCounter (fsLit "RET_UNBOXED_TUP_ctr")
; bumpHistogram (fsLit "RET_UNBOXED_TUP_hst") arity }
-- -----------------------------------------------------------------------------
-- Ticky calls
-- Ticks at a *call site*:
tickyDirectCall :: RepArity -> [StgArg] -> FCode ()
tickyDirectCall arity args
| args `lengthIs` arity = tickyKnownCallExact
| otherwise = do tickyKnownCallExtraArgs
tickySlowCallPat (map argPrimRep (drop arity args))
tickyKnownCallTooFewArgs :: FCode ()
tickyKnownCallTooFewArgs = ifTicky $ bumpTickyCounter (fsLit "KNOWN_CALL_TOO_FEW_ARGS_ctr")
tickyKnownCallExact :: FCode ()
tickyKnownCallExact = ifTicky $ bumpTickyCounter (fsLit "KNOWN_CALL_ctr")
tickyKnownCallExtraArgs :: FCode ()
tickyKnownCallExtraArgs = ifTicky $ bumpTickyCounter (fsLit "KNOWN_CALL_EXTRA_ARGS_ctr")
tickyUnknownCall :: FCode ()
tickyUnknownCall = ifTicky $ bumpTickyCounter (fsLit "UNKNOWN_CALL_ctr")
-- Tick for the call pattern at slow call site (i.e. in addition to
-- tickyUnknownCall, tickyKnownCallExtraArgs, etc.)
tickySlowCall :: LambdaFormInfo -> [StgArg] -> FCode ()
tickySlowCall _ [] = return ()
tickySlowCall lf_info args = do
-- see Note [Ticky for slow calls]
if isKnownFun lf_info
then tickyKnownCallTooFewArgs
else tickyUnknownCall
tickySlowCallPat (map argPrimRep args)
tickySlowCallPat :: [PrimRep] -> FCode ()
tickySlowCallPat args = ifTicky $ do
platform <- profilePlatform <$> getProfile
let argReps = map (toArgRep platform) args
(_, n_matched) = slowCallPattern argReps
if n_matched > 0 && args `lengthIs` n_matched
then bumpTickyLbl $ mkRtsSlowFastTickyCtrLabel $ concatMap (map Data.Char.toLower . argRepString) argReps
else bumpTickyCounter $ fsLit "VERY_SLOW_CALL_ctr"
{-
Note [Ticky for slow calls]
~~~~~~~~~~~~~~~~~~~~~~~~~~~
Terminology is unfortunately a bit mixed up for these calls. codeGen
uses "slow call" to refer to unknown calls and under-saturated known
calls.
Nowadays, though (ie as of the eval/apply paper), the significantly
slower calls are actually just a subset of these: the ones with no
built-in argument pattern (cf GHC.StgToCmm.ArgRep.slowCallPattern)
So for ticky profiling, we split slow calls into
"SLOW_CALL_fast_<pattern>_ctr" (those matching a built-in pattern) and
VERY_SLOW_CALL_ctr (those without a built-in pattern; these are very
bad for both space and time).
-}
-- -----------------------------------------------------------------------------
-- Ticky allocation
tickyDynAlloc :: Maybe Id -> SMRep -> LambdaFormInfo -> FCode ()
-- Called when doing a dynamic heap allocation; the LambdaFormInfo
-- used to distinguish between closure types
--
-- TODO what else to count while we're here?
tickyDynAlloc mb_id rep lf = ifTicky $ do
profile <- getProfile
let platform = profilePlatform profile
bytes = platformWordSizeInBytes platform * heapClosureSizeW profile rep
countGlobal tot ctr = do
bumpTickyCounterBy tot bytes
bumpTickyCounter ctr
countSpecific = ifTickyAllocd $ case mb_id of
Nothing -> return ()
Just id -> do
let ctr_lbl = mkRednCountsLabel (idName id)
registerTickyCtr ctr_lbl
bumpTickyAllocd ctr_lbl bytes
-- TODO are we still tracking "good stuff" (_gds) versus
-- administrative (_adm) versus slop (_slp)? I'm going with all _gds
-- for now, since I don't currently know neither if we do nor how to
-- distinguish. NSF Mar 2013
if | isConRep rep ->
ifTickyDynThunk countSpecific >>
countGlobal (fsLit "ALLOC_CON_gds") (fsLit "ALLOC_CON_ctr")
| isThunkRep rep ->
ifTickyDynThunk countSpecific >>
if lfUpdatable lf
then countGlobal (fsLit "ALLOC_THK_gds") (fsLit "ALLOC_UP_THK_ctr")
else countGlobal (fsLit "ALLOC_THK_gds") (fsLit "ALLOC_SE_THK_ctr")
| isFunRep rep ->
countSpecific >>
countGlobal (fsLit "ALLOC_FUN_gds") (fsLit "ALLOC_FUN_ctr")
| otherwise -> panic "How is this heap object not a con, thunk, or fun?"
tickyAllocHeap ::
Bool -> -- is this a genuine allocation? As opposed to
-- GHC.StgToCmm.Layout.adjustHpBackwards
VirtualHpOffset -> FCode ()
-- Called when doing a heap check [TICK_ALLOC_HEAP]
-- Must be lazy in the amount of allocation!
tickyAllocHeap genuine hp
= ifTicky $
do { platform <- getPlatform
; ticky_ctr <- getTickyCtrLabel
; emit $ catAGraphs $
-- only test hp from within the emit so that the monadic
-- computation itself is not strict in hp (cf knot in
-- GHC.StgToCmm.Monad.getHeapUsage)
if hp == 0 then []
else let !bytes = platformWordSizeInBytes platform * hp in [
-- Bump the allocation total in the closure's StgEntCounter
addToMem (rEP_StgEntCounter_allocs platform)
(CmmLit (cmmLabelOffB ticky_ctr (pc_OFFSET_StgEntCounter_allocs (platformConstants platform))))
bytes,
-- Bump the global allocation total ALLOC_HEAP_tot
addToMemLbl (bWord platform)
(mkRtsCmmDataLabel (fsLit "ALLOC_HEAP_tot"))
bytes,
-- Bump the global allocation counter ALLOC_HEAP_ctr
if not genuine then mkNop
else addToMemLbl (bWord platform)
(mkRtsCmmDataLabel (fsLit "ALLOC_HEAP_ctr"))
1
]}
--------------------------------------------------------------------------------
-- these three are only called from GHC.Cmm.Parser (ie ultimately from the RTS)
-- the units are bytes
tickyAllocPrim :: CmmExpr -- ^ size of the full header, in bytes
-> CmmExpr -- ^ size of the payload, in bytes
-> CmmExpr -> FCode ()
tickyAllocPrim _hdr _goods _slop = ifTicky $ do
bumpTickyCounter (fsLit "ALLOC_PRIM_ctr")
bumpTickyCounterByE (fsLit "ALLOC_PRIM_adm") _hdr
bumpTickyCounterByE (fsLit "ALLOC_PRIM_gds") _goods
bumpTickyCounterByE (fsLit "ALLOC_PRIM_slp") _slop
tickyAllocThunk :: CmmExpr -> CmmExpr -> FCode ()
tickyAllocThunk _goods _slop = ifTicky $ do
-- TODO is it ever called with a Single-Entry thunk?
bumpTickyCounter (fsLit "ALLOC_UP_THK_ctr")
bumpTickyCounterByE (fsLit "ALLOC_THK_gds") _goods
bumpTickyCounterByE (fsLit "ALLOC_THK_slp") _slop
tickyAllocPAP :: CmmExpr -> CmmExpr -> FCode ()
tickyAllocPAP _goods _slop = ifTicky $ do
bumpTickyCounter (fsLit "ALLOC_PAP_ctr")
bumpTickyCounterByE (fsLit "ALLOC_PAP_gds") _goods
bumpTickyCounterByE (fsLit "ALLOC_PAP_slp") _slop
tickyHeapCheck :: FCode ()
tickyHeapCheck = ifTicky $ bumpTickyCounter (fsLit "HEAP_CHK_ctr")
tickyStackCheck :: FCode ()
tickyStackCheck = ifTicky $ bumpTickyCounter (fsLit "STK_CHK_ctr")
-- -----------------------------------------------------------------------------
-- Ticky for tag inference characterisation
-- | Predicted a pointer would be tagged correctly (GHC will crash if not so no miss case)
tickyTagged :: FCode ()
tickyTagged = ifTickyTag $ bumpTickyCounter (fsLit "TAG_TAGGED_pred")
-- | Pass a boolean expr indicating if tag was present.
tickyUntagged :: CmmExpr -> FCode ()
tickyUntagged e = do
ifTickyTag $ bumpTickyCounter (fsLit "TAG_UNTAGGED_pred")
ifTickyTag $ bumpTickyCounterByE (fsLit "TAG_UNTAGGED_miss") e
-- | Called when for `case v of ...` we can avoid entering v based on
-- tag inference information.
tickyTagSkip :: Unique -> Id -> FCode ()
tickyTagSkip unique id = ifTickyTag $ do
let ctr_lbl = mkTagHitLabel (idName id) unique
registerTickyCtr ctr_lbl
bumpTickyTagSkip ctr_lbl
-- -----------------------------------------------------------------------------
-- Ticky utils
isEnabled :: (StgToCmmConfig -> Bool) -> FCode Bool
isEnabled = flip fmap getStgToCmmConfig
runIfFlag :: (StgToCmmConfig -> Bool) -> FCode () -> FCode ()
runIfFlag f = whenM (f <$> getStgToCmmConfig)
ifTicky :: FCode () -> FCode ()
ifTicky = runIfFlag stgToCmmDoTicky
ifTickyTag :: FCode () -> FCode ()
ifTickyTag = runIfFlag stgToCmmTickyTag
ifTickyAllocd :: FCode () -> FCode ()
ifTickyAllocd = runIfFlag stgToCmmTickyAllocd
ifTickyLNE :: FCode () -> FCode ()
ifTickyLNE = runIfFlag stgToCmmTickyLNE
ifTickyDynThunk :: FCode () -> FCode ()
ifTickyDynThunk = runIfFlag stgToCmmTickyDynThunk
bumpTickyCounter :: FastString -> FCode ()
bumpTickyCounter = bumpTickyLbl . mkRtsCmmDataLabel
bumpTickyCounterBy :: FastString -> Int -> FCode ()
bumpTickyCounterBy = bumpTickyLblBy . mkRtsCmmDataLabel
bumpTickyCounterByE :: FastString -> CmmExpr -> FCode ()
bumpTickyCounterByE lbl = bumpTickyLblByE (mkRtsCmmDataLabel lbl)
bumpTickyEntryCount :: CLabel -> FCode ()
bumpTickyEntryCount lbl = do
platform <- getPlatform
bumpTickyLit (cmmLabelOffB lbl (pc_OFFSET_StgEntCounter_entry_count (platformConstants platform)))
bumpTickyAllocd :: CLabel -> Int -> FCode ()
bumpTickyAllocd lbl bytes = do
platform <- getPlatform
bumpTickyLitBy (cmmLabelOffB lbl (pc_OFFSET_StgEntCounter_entry_count (platformConstants platform))) bytes
bumpTickyTagSkip :: CLabel -> FCode ()
bumpTickyTagSkip lbl = do
platform <- getPlatform
bumpTickyLitBy (cmmLabelOffB lbl (pc_OFFSET_StgEntCounter_entry_count (platformConstants platform))) 1
bumpTickyLbl :: CLabel -> FCode ()
bumpTickyLbl lhs = bumpTickyLitBy (cmmLabelOffB lhs 0) 1
bumpTickyLblBy :: CLabel -> Int -> FCode ()
bumpTickyLblBy lhs = bumpTickyLitBy (cmmLabelOffB lhs 0)
bumpTickyLblByE :: CLabel -> CmmExpr -> FCode ()
bumpTickyLblByE lhs = bumpTickyLitByE (cmmLabelOffB lhs 0)
bumpTickyLit :: CmmLit -> FCode ()
bumpTickyLit lhs = bumpTickyLitBy lhs 1
bumpTickyLitBy :: CmmLit -> Int -> FCode ()
bumpTickyLitBy lhs n = do
platform <- getPlatform
emit (addToMem (bWord platform) (CmmLit lhs) n)
bumpTickyLitByE :: CmmLit -> CmmExpr -> FCode ()
bumpTickyLitByE lhs e = do
platform <- getPlatform
emit (addToMemE (bWord platform) (CmmLit lhs) e)
bumpHistogram :: FastString -> Int -> FCode ()
bumpHistogram lbl n = do
platform <- getPlatform
let offset = n `min` (pc_TICKY_BIN_COUNT (platformConstants platform) - 1)
emit (addToMem (bWord platform)
(cmmIndexExpr platform
(wordWidth platform)
(CmmLit (CmmLabel (mkRtsCmmDataLabel lbl)))
(CmmLit (CmmInt (fromIntegral offset) (wordWidth platform))))
1)
------------------------------------------------------------------
-- Showing the "type category" for ticky-ticky profiling
showTypeCategory :: Type -> Char
{-
+ dictionary
> function
{C,I,F,D,W} char, int, float, double, word
{c,i,f,d,w} unboxed ditto
T tuple
P other primitive type
p unboxed ditto
L list
E enumeration type
S other single-constructor type
M other multi-constructor data-con type
. other type
- reserved for others to mark as "uninteresting"
Accurate as of Mar 2013, but I eliminated the Array category instead
of updating it, for simplicity. It's in P/p, I think --NSF
-}
showTypeCategory ty
| isDictTy ty = '+'
| otherwise = case tcSplitTyConApp_maybe ty of
Nothing -> '.'
Just (tycon, _) ->
let anyOf us = getUnique tycon `elem` us in
case () of
_ | anyOf [funTyConKey] -> '>'
| anyOf [charTyConKey] -> 'C'
| anyOf [charPrimTyConKey] -> 'c'
| anyOf [doubleTyConKey] -> 'D'
| anyOf [doublePrimTyConKey] -> 'd'
| anyOf [floatTyConKey] -> 'F'
| anyOf [floatPrimTyConKey] -> 'f'
| anyOf [intTyConKey, int8TyConKey, int16TyConKey, int32TyConKey, int64TyConKey] -> 'I'
| anyOf [intPrimTyConKey, int8PrimTyConKey, int16PrimTyConKey, int32PrimTyConKey, int64PrimTyConKey] -> 'i'
| anyOf [wordTyConKey, word8TyConKey, word16TyConKey, word32TyConKey, word64TyConKey] -> 'W'
| anyOf [wordPrimTyConKey, word8PrimTyConKey, word16PrimTyConKey, word32PrimTyConKey, word64PrimTyConKey] -> 'w'
| anyOf [listTyConKey] -> 'L'
| isUnboxedTupleTyCon tycon -> 't'
| isTupleTyCon tycon -> 'T'
| isPrimTyCon tycon -> 'P'
| isEnumerationTyCon tycon -> 'E'
| isJust (tyConSingleDataCon_maybe tycon) -> 'S'
| otherwise -> 'M' -- oh, well...