Make profiling output include better source span

[SeungheonOh]

Describe the feature you'd like

plutus/plutus-tx-plugin/src/PlutusTx/Compiler/Expr.hs

Lines 662 to 687 in a8a5a35

	maybeProfileRhs
	:: CompilingDefault uni fun m ann
	=> GHC.Var
	-> PLCVar uni
	-> PIRTerm uni fun
	-> m (PIRTerm uni fun)
	maybeProfileRhs ghcVar var t = do
	CompileContext {ccOpts = compileOpts} <- ask
	let
	nameStr = GHC.occNameString $ GHC.occName $ GHC.varName $ ghcVar
	displayName = T.pack $
	case getVarSourceSpan ghcVar of
	-- When module is not compiled and GHC is using cached build from previous build, it will
	-- lack source span. There's nothing much we can do about this here since this is GHC
	-- behavior. Issue #7203
	Nothing -> nameStr
	Just src -> nameStr <> " (" <> show (src ^. srcSpanIso) <> ")"
	ty = PLC._varDeclType var
	isFunctionOrAbstraction = case ty of PLC.TyFun {} -> True; PLC.TyForall {} -> True; _ -> False
	-- Trace only if profiling is on *and* the thing being defined is a function
	if coProfile compileOpts == All && isFunctionOrAbstraction
	then do
	thunk <- PLC.freshName "thunk"
	pure $ entryExitTracingInside thunk displayName t ty
	else pure t

This function is used to insert call profiling information to each function calls which is used to run profiling and also call trace information. Currently, it gets source span from GHC.Var; source span attached to GHC.Var is only available if the module GHC.Var resides in gets compiled from scratch without compilation cache. So, to get accurate source spans for these profiling traces, one must always run cabal clean and if not it will add traces without source span.

It should be possible now to get accurate srcspan without needing cabal clean with #7640

Describe alternatives you've considered

No response