Ticky profiling improvements.wip/ticky-eventlog-rebase

This adds a number of changes to ticky-ticky profiling.

When an executable is profiled with IPE profiling it's now possible to
associate id-related ticky counters to their source location.
This works by emitting the info table address as part of the counter
which can be looked up in the IPE table.

Add a `-ticky-ap-thunk` flag. This flag prevents the use of some standard thunks
which are precompiled into the RTS. This means reduced cache locality
and increased code size. But it allows better attribution of execution
cost to specific source locations instead of simple attributing it to
the standard thunk.

ticky-ticky now uses the `arg` field to emit additional information
about counters in json format. When ticky-ticky is used in combination
with the eventlog eventlog2html can be used to generate a html table
from the eventlog similar to the old text output for ticky-ticky.

1 files changed, 1 insertions, 0 deletions

diff --git a/compiler/GHC/Cmm/Parser.y b/compiler/GHC/Cmm/Parser.y
index 6e6a130233..100e4f9b65 100644
--- a/compiler/GHC/Cmm/Parser.y
+++ b/compiler/GHC/Cmm/Parser.y
@@ -1519,6 +1519,7 @@ parseCmmFile dflags this_mod home_unit filename = do
         let fstate = F.initFCodeState (profilePlatform $ targetProfile dflags)
         let fcode = do
               ((), cmm) <- getCmm $ unEC code "global" (initEnv (targetProfile dflags)) [] >> return ()
+              -- See Note [Mapping Info Tables to Source Positions] (IPE Maps)
               let used_info = map (cmmInfoTableToInfoProvEnt this_mod)
                                               (mapMaybe topInfoTable cmm)
               ((), cmm2) <- getCmm $ mapM_ emitInfoTableProv used_info